source: palm/trunk/DOC/app/chapter_4.1.html @ 57

Last change on this file since 57 was 57, checked in by raasch, 18 years ago

preliminary update of further changes, advec_particles is not running!

  • Property svn:keywords set to Id
File size: 185.1 KB
Line 
1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2<html><head>
3
4
5
6
7
8
9
10
11
12
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23  <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1"><title>PALM chapter 4.1</title></head>
24<body>
25
26
27
28
29
30
31
32
33
34
35<h3><a name="chapter4.1"></a>4.1 Initialization parameters</h3>
36
37
38
39
40
41
42
43
44
45
46<br>
47
48
49
50
51
52
53
54
55
56
57<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
58
59
60
61
62
63
64
65
66
67
68  <tbody>
69
70
71
72
73
74
75
76
77
78
79    <tr>
80
81
82
83
84
85
86
87
88
89
90      <td style="vertical-align: top;"><font size="4"><b>Parameter name</b></font></td>
91
92
93
94
95
96
97
98
99
100
101      <td style="vertical-align: top;"><font size="4"><b>Type</b></font></td>
102
103
104
105
106
107
108
109
110
111
112      <td style="vertical-align: top;">
113     
114     
115     
116     
117     
118     
119     
120     
121     
122     
123      <p><b><font size="4">Default</font></b> <br>
124
125
126
127
128
129
130
131
132
133
134      <b><font size="4">value</font></b></p>
135
136
137
138
139
140
141
142
143
144
145      </td>
146
147
148
149
150
151
152
153
154
155
156      <td style="vertical-align: top;"><font size="4"><b>Explanation</b></font></td>
157
158
159
160
161
162
163
164
165
166
167    </tr>
168
169
170
171
172
173
174
175
176
177
178    <tr>
179
180
181
182
183
184
185
186
187
188
189      <td style="vertical-align: top;">
190     
191     
192     
193     
194     
195     
196     
197     
198     
199     
200      <p><a name="adjust_mixing_length"></a><b>adjust_mixing_length</b></p>
201
202
203
204
205
206
207
208
209
210
211      </td>
212
213
214
215
216
217
218
219
220
221
222      <td style="vertical-align: top;">L</td>
223
224
225
226
227
228
229
230
231
232
233      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
234
235
236
237
238
239
240
241
242
243
244      <td style="vertical-align: top;">
245     
246     
247     
248     
249     
250     
251     
252     
253     
254     
255      <p style="font-style: normal;">Near-surface adjustment of the
256mixing length to the Prandtl-layer law.&nbsp; </p>
257
258
259
260
261
262
263
264
265
266
267     
268     
269     
270     
271     
272     
273     
274     
275     
276     
277      <p>Usually the mixing length in LES models l<sub>LES</sub>
278depends (as in PALM) on the grid size and is possibly restricted
279further in case of stable stratification and near the lower wall (see
280parameter <a href="#wall_adjustment">wall_adjustment</a>).
281With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span>
282the Prandtl' mixing length l<sub>PR</sub> = kappa * z/phi is calculated
283and the mixing length actually used in the model is set l = MIN (l<sub>LES</sub>,
284l<sub>PR</sub>). This usually gives a decrease of the mixing length at
285the bottom boundary and considers the fact that eddy sizes
286decrease in the vicinity of the wall.&nbsp; </p>
287
288
289
290
291
292
293
294
295
296
297     
298     
299     
300     
301     
302     
303     
304     
305     
306     
307      <p style="font-style: normal;"><b>Warning:</b> So far, there is
308no good experience with <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> !&nbsp; </p>
309
310
311
312
313
314
315
316
317
318
319     
320     
321     
322     
323     
324     
325     
326     
327     
328     
329      <p>With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> and the Prandtl-layer being
330switched on (see <a href="#prandtl_layer">prandtl_layer</a>) <span style="font-style: italic;">'(u*)** 2+neumann'</span>
331should always be set as the lower boundary condition for the TKE (see <a href="#bc_e_b">bc_e_b</a>),
332otherwise the near-surface value of the TKE is not in agreement with
333the Prandtl-layer law (Prandtl-layer law and Prandtl-Kolmogorov-Ansatz
334should provide the same value for K<sub>m</sub>). A warning is given,
335if this is not the case.</p>
336
337
338
339
340
341
342
343
344
345
346      </td>
347
348
349
350
351
352
353
354
355
356
357    </tr>
358
359
360
361
362
363
364
365
366
367
368    <tr>
369
370
371
372
373
374
375
376
377
378
379      <td style="vertical-align: top;">
380     
381     
382     
383     
384     
385     
386     
387     
388     
389     
390      <p><a name="alpha_surface"></a><b>alpha_surface</b></p>
391
392
393
394
395
396
397
398
399
400
401      </td>
402
403
404
405
406
407
408
409
410
411
412      <td style="vertical-align: top;">R<br>
413
414
415
416
417
418
419
420
421
422
423      </td>
424
425
426
427
428
429
430
431
432
433
434      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
435
436
437
438
439
440
441
442
443
444
445      </td>
446
447
448
449
450
451
452
453
454
455
456      <td style="vertical-align: top;">
457     
458     
459     
460     
461     
462     
463     
464     
465     
466     
467      <p style="font-style: normal;">Inclination of the model domain
468with respect to the horizontal (in degrees).&nbsp; </p>
469
470
471
472
473
474
475
476
477
478
479     
480     
481     
482     
483     
484     
485     
486     
487     
488     
489      <p style="font-style: normal;">By means of <b>alpha_surface</b>
490the model domain can be inclined in x-direction with respect to the
491horizontal. In this way flows over inclined surfaces (e.g. drainage
492flows, gravity flows) can be simulated. In case of <b>alpha_surface </b>/=
493      <span style="font-style: italic;">0</span> the buoyancy term
494appears both in
495the equation of motion of the u-component and of the w-component.<br>
496
497
498
499
500
501
502
503
504
505
506      </p>
507
508
509
510
511
512
513
514
515
516
517     
518     
519     
520     
521     
522     
523     
524     
525     
526     
527      <p style="font-style: normal;">An inclination is only possible in
528case of cyclic horizontal boundary conditions along x AND y (see <a href="#bc_lr">bc_lr</a>
529and <a href="#bc_ns">bc_ns</a>) and <a href="#topography">topography</a> = <span style="font-style: italic;">'flat'</span>. </p>
530
531
532
533
534
535
536
537
538
539
540     
541     
542     
543     
544     
545     
546     
547     
548     
549     
550      <p>Runs with inclined surface still require additional
551user-defined code as well as modifications to the default code. Please
552ask the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/PALM_group.html#0">PALM
553developer&nbsp; group</a>.</p>
554
555
556
557
558
559
560
561
562
563
564      </td>
565
566
567
568
569
570
571
572
573
574
575    </tr>
576
577
578
579
580
581
582
583
584
585
586    <tr>
587
588
589
590
591
592
593
594
595
596
597      <td style="vertical-align: top;">
598     
599     
600     
601     
602     
603     
604     
605     
606     
607     
608      <p><a name="bc_e_b"></a><b>bc_e_b</b></p>
609
610
611
612
613
614
615
616
617
618
619      </td>
620
621
622
623
624
625
626
627
628
629
630      <td style="vertical-align: top;">C * 20</td>
631
632
633
634
635
636
637
638
639
640
641      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
642
643
644
645
646
647
648
649
650
651
652      <td style="vertical-align: top;">
653     
654     
655     
656     
657     
658     
659     
660     
661     
662     
663      <p style="font-style: normal;">Bottom boundary condition of the
664TKE.&nbsp; </p>
665
666
667
668
669
670
671
672
673
674
675     
676     
677     
678     
679     
680     
681     
682     
683     
684     
685      <p><b>bc_e_b</b> may be set to&nbsp;<span style="font-style: italic;">'neumann'</span> or <span style="font-style: italic;">'(u*) ** 2+neumann'</span>. <b>bc_e_b</b>
686= <span style="font-style: italic;">'neumann'</span> yields to
687e(k=0)=e(k=1) (Neumann boundary condition), where e(k=1) is calculated
688via the prognostic TKE equation. Choice of <span style="font-style: italic;">'(u*)**2+neumann'</span> also yields to
689e(k=0)=e(k=1), but the TKE at the Prandtl-layer top (k=1) is calculated
690diagnostically by e(k=1)=(us/0.1)**2. However, this is only allowed if
691a Prandtl-layer is used (<a href="#prandtl_layer">prandtl_layer</a>).
692If this is not the case, a warning is given and <b>bc_e_b</b> is reset
693to <span style="font-style: italic;">'neumann'</span>.&nbsp; </p>
694
695
696
697
698
699
700
701
702
703
704     
705     
706     
707     
708     
709     
710     
711     
712     
713     
714      <p style="font-style: normal;">At the top boundary a Neumann
715boundary condition is generally used: (e(nz+1) = e(nz)).</p>
716
717
718
719
720
721
722
723
724
725
726      </td>
727
728
729
730
731
732
733
734
735
736
737    </tr>
738
739
740
741
742
743
744
745
746
747
748    <tr>
749
750
751
752
753
754
755
756
757
758
759      <td style="vertical-align: top;">
760     
761     
762     
763     
764     
765     
766     
767     
768     
769     
770      <p><a name="bc_lr"></a><b>bc_lr</b></p>
771
772
773
774
775
776
777
778
779
780
781      </td>
782
783
784
785
786
787
788
789
790
791
792      <td style="vertical-align: top;">C * 20</td>
793
794
795
796
797
798
799
800
801
802
803      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
804
805
806
807
808
809
810
811
812
813
814      <td style="vertical-align: top;">Boundary
815condition along x (for all quantities).<br>
816
817
818
819
820
821
822
823
824
825
826      <br>
827
828
829
830
831
832
833
834
835
836
837By default, a cyclic boundary condition is used along x.<br>
838
839
840
841
842
843
844
845
846
847
848      <br>
849
850
851
852
853
854
855
856
857
858
859      <span style="font-weight: bold;">bc_lr</span> may also be
860assigned the values <span style="font-style: italic;">'dirichlet/neumann'</span>
861(inflow from left, outflow to the right) or <span style="font-style: italic;">'neumann/dirichlet'</span> (inflow from
862right, outflow to the left). This requires the multi-grid method to be
863used for solving the Poisson equation for perturbation pressure (see <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">psolver</a>)
864and it also requires cyclic boundary conditions along y (see<br>
865
866
867
868
869
870
871
872
873
874
875      <a href="#bc_ns">bc_ns</a>).<br>
876
877
878
879
880
881
882
883
884
885
886      <br>
887
888
889
890
891
892
893
894
895
896
897In case of these non-cyclic lateral boundaries, a Dirichlet condition
898is used at the inflow for all quantities (initial vertical profiles -
899see <a href="#initializing_actions">initializing_actions</a>
900- are fixed during the run) except u, to which a Neumann (zero
901gradient) condition is applied. At the outflow, a Neumann (zero
902gradient) condition is used for all quantities except v, which is set
903to its horizontal average along the outflow (e.g. v(k,:,nx+1) =
904average_along_y( v(k,:,nx)), and except w, which is set to zero
905(Dirichlet condition). These conditions ensure the velocity field to be
906free of divergence at the inflow and at the outflow. For perturbation
907pressure Neumann (zero gradient) conditions are assumed both at the
908inflow and at the outflow.<br>
909
910
911
912
913
914
915
916
917
918
919      <br>
920
921
922
923
924
925
926
927
928
929
930When using non-cyclic lateral boundaries, a filter is applied to the
931velocity field in the vicinity of the outflow in order to suppress any
932reflections of outgoing disturbances (see <a href="#km_damp_max">km_damp_max</a>
933and <a href="#outflow_damping_width">outflow_damping_width</a>).<br>
934
935
936
937
938
939
940
941
942
943
944      <br>
945
946
947
948
949
950
951
952
953
954
955In order to maintain a turbulent state of the flow, it may be
956neccessary to continuously impose perturbations on the horizontal
957velocity field in the vicinity of the inflow throughout the whole run.
958This can be switched on using <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#create_disturbances">create_disturbances</a>.
959The horizontal range to which these perturbations are applied is
960controlled by the parameters <a href="#inflow_disturbance_begin">inflow_disturbance_begin</a>
961and <a href="#inflow_disturbance_end">inflow_disturbance_end</a>.
962The vertical range and the perturbation amplitude are given by <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_level_b</a>,
963      <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_level_t</a>,
964and <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_amplitude</a>.
965The time interval at which perturbations are to be imposed is set by <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#dt_disturb">dt_disturb</a>.<br>
966
967
968
969
970
971
972
973
974
975
976      <br>
977
978
979
980
981
982
983
984
985
986
987In case of non-cyclic horizontal boundaries <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#call_psolver_at_all_substeps">call_psolver
988at_all_substeps</a> = .T. should be used.<br>
989
990
991
992
993
994
995
996
997
998
999      <br>
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010      <span style="font-weight: bold;">Note:</span><br>
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021Using non-cyclic lateral boundaries requires very sensitive adjustments
1022of the inflow (vertical profiles) and the bottom boundary conditions,
1023e.g. a surface heating should not be applied near the inflow boundary
1024because this may significantly disturb the inflow. Please check the
1025model results very carefully.</td>
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036    </tr>
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047    <tr>
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058      <td style="vertical-align: top;">
1059     
1060     
1061     
1062     
1063     
1064     
1065     
1066     
1067     
1068     
1069      <p><a name="bc_ns"></a><b>bc_ns</b></p>
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080      </td>
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091      <td style="vertical-align: top;">C * 20</td>
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113      <td style="vertical-align: top;">Boundary
1114condition along y (for all quantities).<br>
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125      <br>
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136By default, a cyclic boundary condition is used along y.<br>
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147      <br>
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158      <span style="font-weight: bold;">bc_ns</span> may also be
1159assigned the values <span style="font-style: italic;">'dirichlet/neumann'</span>
1160(inflow from rear ("north"), outflow to the front ("south")) or <span style="font-style: italic;">'neumann/dirichlet'</span>
1161(inflow from front ("south"), outflow to the rear ("north")). This
1162requires the multi-grid
1163method to be used for solving the Poisson equation for perturbation
1164pressure (see <a href="chapter_4.2.html#psolver">psolver</a>)
1165and it also requires cyclic boundary conditions along x (see<br>
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176      <a href="#bc_lr">bc_lr</a>).<br>
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187      <br>
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198In case of these non-cyclic lateral boundaries, a Dirichlet condition
1199is used at the inflow for all quantities (initial vertical profiles -
1200see <a href="#initializing_actions">initializing_actions</a>
1201- are fixed during the run) except v, to which a Neumann (zero
1202gradient) condition is applied. At the outflow, a Neumann (zero
1203gradient) condition is used for all quantities except u, which is set
1204to its horizontal average along the outflow (e.g. u(k,ny+1,:) =
1205average_along_x( u(k,ny,:)), and except w, which is set to zero
1206(Dirichlet condition). These conditions ensure the velocity field to be
1207free of divergence at the inflow and at the outflow. For perturbation
1208pressure Neumann (zero gradient) conditions are assumed both at the
1209inflow and at the outflow.<br>
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220      <br>
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231For further details regarding non-cyclic lateral boundary conditions
1232see <a href="#bc_lr">bc_lr</a>.</td>
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243    </tr>
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254    <tr>
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265      <td style="vertical-align: top;">
1266     
1267     
1268     
1269     
1270     
1271     
1272     
1273     
1274     
1275     
1276      <p><a name="bc_p_b"></a><b>bc_p_b</b></p>
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287      </td>
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298      <td style="vertical-align: top;">C * 20</td>
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320      <td style="vertical-align: top;">
1321     
1322     
1323     
1324     
1325     
1326     
1327     
1328     
1329     
1330     
1331      <p style="font-style: normal;">Bottom boundary condition of the
1332perturbation pressure.&nbsp; </p>
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343     
1344     
1345     
1346     
1347     
1348     
1349     
1350     
1351     
1352     
1353      <p>Allowed values are <span style="font-style: italic;">'dirichlet'</span>,
1354      <span style="font-style: italic;">'neumann'</span> and <span style="font-style: italic;">'neumann+inhomo'</span>.&nbsp; <span style="font-style: italic;">'dirichlet'</span> sets
1355p(k=0)=0.0,&nbsp; <span style="font-style: italic;">'neumann'</span>
1356sets p(k=0)=p(k=1). <span style="font-style: italic;">'neumann+inhomo'</span>
1357corresponds to an extended Neumann boundary condition where heat flux
1358or temperature inhomogeneities near the
1359surface (pt(k=1))&nbsp; are additionally regarded (see Shen and LeClerc
1360(1995, Q.J.R. Meteorol. Soc.,
13611209)). This condition is only permitted with the Prandtl-layer
1362switched on (<a href="#prandtl_layer">prandtl_layer</a>),
1363otherwise the run is terminated.&nbsp; </p>
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374     
1375     
1376     
1377     
1378     
1379     
1380     
1381     
1382     
1383     
1384      <p>Since at the bottom boundary of the model the vertical
1385velocity
1386disappears (w(k=0) = 0.0), the consistent Neumann condition (<span style="font-style: italic;">'neumann'</span> or <span style="font-style: italic;">'neumann+inhomo'</span>) dp/dz = 0 should
1387be used, which leaves the vertical component w unchanged when the
1388pressure solver is applied. Simultaneous use of the Neumann boundary
1389conditions both at the bottom and at the top boundary (<a href="#bc_p_t">bc_p_t</a>)
1390usually yields no consistent solution for the perturbation pressure and
1391should be avoided.</p>
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402      </td>
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413    </tr>
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424    <tr>
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435      <td style="vertical-align: top;">
1436     
1437     
1438     
1439     
1440     
1441     
1442     
1443     
1444     
1445     
1446      <p><a name="bc_p_t"></a><b>bc_p_t</b></p>
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457      </td>
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468      <td style="vertical-align: top;">C * 20</td>
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490      <td style="vertical-align: top;">
1491     
1492     
1493     
1494     
1495     
1496     
1497     
1498     
1499     
1500     
1501      <p style="font-style: normal;">Top boundary condition of the
1502perturbation pressure.&nbsp; </p>
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513     
1514     
1515     
1516     
1517     
1518     
1519     
1520     
1521     
1522     
1523      <p style="font-style: normal;">Allowed values are <span style="font-style: italic;">'dirichlet'</span> (p(k=nz+1)= 0.0) or <span style="font-style: italic;">'neumann'</span>
1524(p(k=nz+1)=p(k=nz)).&nbsp; </p>
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535     
1536     
1537     
1538     
1539     
1540     
1541     
1542     
1543     
1544     
1545      <p>Simultaneous use of Neumann boundary conditions both at the
1546top and bottom boundary (<a href="#bc_p_b">bc_p_b</a>)
1547usually yields no consistent solution for the perturbation pressure and
1548should be avoided. Since at the bottom boundary the Neumann
1549condition&nbsp; is a good choice (see <a href="#bc_p_b">bc_p_b</a>),
1550a Dirichlet condition should be set at the top boundary.</p>
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561      </td>
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572    </tr>
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583    <tr>
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594      <td style="vertical-align: top;">
1595     
1596     
1597     
1598     
1599     
1600     
1601     
1602     
1603     
1604     
1605      <p><a name="bc_pt_b"></a><b>bc_pt_b</b></p>
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616      </td>
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627      <td style="vertical-align: top;">C*20</td>
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649      <td style="vertical-align: top;">
1650     
1651     
1652     
1653     
1654     
1655     
1656     
1657     
1658     
1659     
1660      <p style="font-style: normal;">Bottom boundary condition of the
1661potential temperature.&nbsp; </p>
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672     
1673     
1674     
1675     
1676     
1677     
1678     
1679     
1680     
1681     
1682      <p>Allowed values are <span style="font-style: italic;">'dirichlet'</span>
1683(pt(k=0) = const. = <a href="#pt_surface">pt_surface</a>
1684+ <a href="#pt_surface_initial_change">pt_surface_initial_change</a>;
1685the user may change this value during the run using user-defined code)
1686and <span style="font-style: italic;">'neumann'</span>
1687(pt(k=0)=pt(k=1)).&nbsp; <br>
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698When a constant surface sensible heat flux is used (<a href="#surface_heatflux">surface_heatflux</a>), <b>bc_pt_b</b> = <span style="font-style: italic;">'neumann'</span>
1699must be used, because otherwise the resolved scale may contribute to
1700the surface flux so that a constant value cannot be guaranteed.</p>
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711      </td>
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722    </tr>
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733    <tr>
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744      <td style="vertical-align: top;">
1745     
1746     
1747     
1748     
1749     
1750     
1751     
1752     
1753     
1754     
1755      <p><a name="pc_pt_t"></a><b>bc_pt_t</b></p>
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766      </td>
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777      <td style="vertical-align: top;">C * 20</td>
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788      <td style="vertical-align: top;"><span style="font-style: italic;">'initial gradient'</span></td>
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799      <td style="vertical-align: top;">
1800     
1801     
1802     
1803     
1804     
1805     
1806     
1807     
1808     
1809     
1810      <p style="font-style: normal;">Top boundary condition of the
1811potential temperature.&nbsp; </p>
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822     
1823     
1824     
1825     
1826     
1827     
1828     
1829     
1830     
1831     
1832      <p>Allowed are the values <span style="font-style: italic;">'dirichlet'
1833      </span>(pt(k=nz+1)
1834does not change during the run), <span style="font-style: italic;">'neumann'</span> (pt(k=nz+1)=pt(k=nz)), and <span style="font-style: italic;">'initial_gradient'</span>.
1835With the 'initial_gradient'-condition the value of the temperature gradient at the top is
1836calculated from the initial
1837temperature profile (see <a href="#pt_surface">pt_surface</a>, <a href="#pt_vertical_gradient">pt_vertical_gradient</a>)
1838by bc_pt_t_val = (pt_init(k=nz+1) -
1839pt_init(k=nz)) / dzu(nz+1).<br>
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850Using this value (assumed constant during the
1851run) the temperature boundary values are calculated as&nbsp; </p>
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862     
1863     
1864     
1865     
1866     
1867     
1868     
1869     
1870     
1871     
1872     
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883     
1884     
1885     
1886     
1887     
1888     
1889     
1890     
1891     
1892     
1893     
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904     
1905     
1906     
1907     
1908     
1909     
1910     
1911     
1912     
1913     
1914      <ul>
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925       
1926       
1927       
1928       
1929       
1930       
1931       
1932       
1933       
1934       
1935        <p style="font-style: normal;">pt(k=nz+1) = pt(k=nz) +
1936bc_pt_t_val * dzu(nz+1)</p>
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947     
1948     
1949     
1950     
1951     
1952     
1953     
1954     
1955     
1956     
1957      </ul>
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968     
1969     
1970     
1971     
1972     
1973     
1974     
1975     
1976     
1977     
1978      <p style="font-style: normal;">(up to k=nz the prognostic
1979equation for the temperature is solved).<br>
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990When a constant sensible heat flux is used at the top boundary (<a href="chapter_4.1.html#top_heatflux">top_heatflux</a>), <b>bc_pt_t</b> = <span style="font-style: italic;">'neumann'</span>
1991must be used, because otherwise the resolved scale may contribute to
1992the top flux so that a constant value cannot be guaranteed.</p>
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003      </td>
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014    </tr>
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025    <tr>
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036      <td style="vertical-align: top;">
2037     
2038     
2039     
2040     
2041     
2042     
2043     
2044     
2045     
2046     
2047      <p><a name="bc_q_b"></a><b>bc_q_b</b></p>
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058      </td>
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069      <td style="vertical-align: top;">C * 20</td>
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091      <td style="vertical-align: top;">
2092     
2093     
2094     
2095     
2096     
2097     
2098     
2099     
2100     
2101     
2102      <p style="font-style: normal;">Bottom boundary condition of the
2103specific humidity / total water content.&nbsp; </p>
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114     
2115     
2116     
2117     
2118     
2119     
2120     
2121     
2122     
2123     
2124      <p>Allowed values are <span style="font-style: italic;">'dirichlet'</span>
2125(q(k=0) = const. = <a href="#q_surface">q_surface</a>
2126+ <a href="#q_surface_initial_change">q_surface_initial_change</a>;
2127the user may change this value during the run using user-defined code)
2128and <span style="font-style: italic;">'neumann'</span>
2129(q(k=0)=q(k=1)).&nbsp; <br>
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140When a constant surface latent heat flux is used (<a href="#surface_waterflux">surface_waterflux</a>), <b>bc_q_b</b> = <span style="font-style: italic;">'neumann'</span>
2141must be used, because otherwise the resolved scale may contribute to
2142the surface flux so that a constant value cannot be guaranteed.</p>
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153      </td>
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164    </tr>
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175    <tr>
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186      <td style="vertical-align: top;">
2187     
2188     
2189     
2190     
2191     
2192     
2193     
2194     
2195     
2196     
2197      <p><a name="bc_q_t"></a><b>bc_q_t</b></p>
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208      </td>
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219      <td style="vertical-align: top;"><span style="font-style: italic;">C
2220* 20</span></td>
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242      <td style="vertical-align: top;">
2243     
2244     
2245     
2246     
2247     
2248     
2249     
2250     
2251     
2252     
2253      <p style="font-style: normal;">Top boundary condition of the
2254specific humidity / total water content.&nbsp; </p>
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265     
2266     
2267     
2268     
2269     
2270     
2271     
2272     
2273     
2274     
2275      <p>Allowed are the values <span style="font-style: italic;">'dirichlet'</span>
2276(q(k=nz) and q(k=nz+1) do
2277not change during the run) and <span style="font-style: italic;">'neumann'</span>.
2278With the Neumann boundary
2279condition the value of the humidity gradient at the top is calculated
2280from the
2281initial humidity profile (see <a href="#q_surface">q_surface</a>, <a href="#q_vertical_gradient">q_vertical_gradient</a>)
2282by: bc_q_t_val = ( q_init(k=nz) - q_init(k=nz-1)) / dzu(nz).<br>
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293Using this value (assumed constant during the run) the humidity
2294boundary values
2295are calculated as&nbsp; </p>
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306     
2307     
2308     
2309     
2310     
2311     
2312     
2313     
2314     
2315     
2316     
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327     
2328     
2329     
2330     
2331     
2332     
2333     
2334     
2335     
2336     
2337     
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348     
2349     
2350     
2351     
2352     
2353     
2354     
2355     
2356     
2357     
2358      <ul>
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369       
2370       
2371       
2372       
2373       
2374       
2375       
2376       
2377       
2378       
2379        <p style="font-style: normal;">q(k=nz+1) =q(k=nz) +
2380bc_q_t_val * dzu(nz+1)</p>
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391     
2392     
2393     
2394     
2395     
2396     
2397     
2398     
2399     
2400     
2401      </ul>
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412     
2413     
2414     
2415     
2416     
2417     
2418     
2419     
2420     
2421     
2422      <p style="font-style: normal;">(up tp k=nz the prognostic
2423equation for q is solved). </p>
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434      </td>
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445    </tr>
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456    <tr>
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467      <td style="vertical-align: top;">
2468     
2469     
2470     
2471     
2472     
2473     
2474     
2475     
2476     
2477     
2478      <p><a name="bc_s_b"></a><b>bc_s_b</b></p>
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489      </td>
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500      <td style="vertical-align: top;">C * 20</td>
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522      <td style="vertical-align: top;">
2523     
2524     
2525     
2526     
2527     
2528     
2529     
2530     
2531     
2532     
2533      <p style="font-style: normal;">Bottom boundary condition of the
2534scalar concentration.&nbsp; </p>
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545     
2546     
2547     
2548     
2549     
2550     
2551     
2552     
2553     
2554     
2555      <p>Allowed values are <span style="font-style: italic;">'dirichlet'</span>
2556(s(k=0) = const. = <a href="#s_surface">s_surface</a>
2557+ <a href="#s_surface_initial_change">s_surface_initial_change</a>;
2558the user may change this value during the run using user-defined code)
2559and <span style="font-style: italic;">'neumann'</span> (s(k=0) =
2560s(k=1)).&nbsp; <br>
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571When a constant surface concentration flux is used (<a href="#surface_scalarflux">surface_scalarflux</a>), <b>bc_s_b</b> = <span style="font-style: italic;">'neumann'</span>
2572must be used, because otherwise the resolved scale may contribute to
2573the surface flux so that a constant value cannot be guaranteed.</p>
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584      </td>
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595    </tr>
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606    <tr>
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617      <td style="vertical-align: top;">
2618     
2619     
2620     
2621     
2622     
2623     
2624     
2625     
2626     
2627     
2628      <p><a name="bc_s_t"></a><b>bc_s_t</b></p>
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639      </td>
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650      <td style="vertical-align: top;">C * 20</td>
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672      <td style="vertical-align: top;">
2673     
2674     
2675     
2676     
2677     
2678     
2679     
2680     
2681     
2682     
2683      <p style="font-style: normal;">Top boundary condition of the
2684scalar concentration.&nbsp; </p>
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695     
2696     
2697     
2698     
2699     
2700     
2701     
2702     
2703     
2704     
2705      <p>Allowed are the values <span style="font-style: italic;">'dirichlet'</span>
2706(s(k=nz) and s(k=nz+1) do
2707not change during the run) and <span style="font-style: italic;">'neumann'</span>.
2708With the Neumann boundary
2709condition the value of the scalar concentration gradient at the top is
2710calculated
2711from the initial scalar concentration profile (see <a href="#s_surface">s_surface</a>,
2712      <a href="#s_vertical_gradient">s_vertical_gradient</a>)
2713by: bc_s_t_val = (s_init(k=nz) - s_init(k=nz-1)) / dzu(nz).<br>
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724Using this value (assumed constant during the run) the concentration
2725boundary values
2726are calculated as </p>
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737     
2738     
2739     
2740     
2741     
2742     
2743     
2744     
2745     
2746     
2747     
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758     
2759     
2760     
2761     
2762     
2763     
2764     
2765     
2766     
2767     
2768     
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779     
2780     
2781     
2782     
2783     
2784     
2785     
2786     
2787     
2788     
2789      <ul>
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800       
2801       
2802       
2803       
2804       
2805       
2806       
2807       
2808       
2809       
2810        <p style="font-style: normal;">s(k=nz+1) = s(k=nz) +
2811bc_s_t_val * dzu(nz+1)</p>
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822     
2823     
2824     
2825     
2826     
2827     
2828     
2829     
2830     
2831     
2832      </ul>
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843     
2844     
2845     
2846     
2847     
2848     
2849     
2850     
2851     
2852     
2853      <p style="font-style: normal;">(up to k=nz the prognostic
2854equation for the scalar concentration is
2855solved).</p>
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866      </td>
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877    </tr>
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888    <tr>
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899      <td style="vertical-align: top;">
2900     
2901     
2902     
2903     
2904     
2905     
2906     
2907     
2908     
2909     
2910      <p><a name="bc_uv_b"></a><b>bc_uv_b</b></p>
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921      </td>
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932      <td style="vertical-align: top;">C * 20</td>
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954      <td style="vertical-align: top;">
2955     
2956     
2957     
2958     
2959     
2960     
2961     
2962     
2963     
2964     
2965      <p style="font-style: normal;">Bottom boundary condition of the
2966horizontal velocity components u and v.&nbsp; </p>
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977     
2978     
2979     
2980     
2981     
2982     
2983     
2984     
2985     
2986     
2987      <p>Allowed values are <span style="font-style: italic;">'dirichlet'
2988      </span>and <span style="font-style: italic;">'neumann'</span>. <b>bc_uv_b</b>
2989= <span style="font-style: italic;">'dirichlet'</span> yields the
2990no-slip condition with u=v=0 at the bottom. Due to the staggered grid
2991u(k=0) and v(k=0) are located at z = - 0,5 * <a href="#dz">dz</a>
2992(below the bottom), while u(k=1) and v(k=1) are located at z = +0,5 *
2993dz. u=v=0 at the bottom is guaranteed using mirror boundary
2994condition:&nbsp; </p>
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005     
3006     
3007     
3008     
3009     
3010     
3011     
3012     
3013     
3014     
3015      <ul>
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026       
3027       
3028       
3029       
3030       
3031       
3032       
3033       
3034       
3035       
3036        <p style="font-style: normal;">u(k=0) = - u(k=1) and v(k=0) = -
3037v(k=1)</p>
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048     
3049     
3050     
3051     
3052     
3053     
3054     
3055     
3056     
3057     
3058      </ul>
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069     
3070     
3071     
3072     
3073     
3074     
3075     
3076     
3077     
3078     
3079      <p style="font-style: normal;">The Neumann boundary condition
3080yields the free-slip condition with u(k=0) = u(k=1) and v(k=0) =
3081v(k=1).
3082With Prandtl - layer switched on, the free-slip condition is not
3083allowed (otherwise the run will be terminated)<font color="#000000">.</font></p>
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094      </td>
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105    </tr>
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116    <tr>
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127      <td style="vertical-align: top;">
3128     
3129     
3130     
3131     
3132     
3133     
3134     
3135     
3136     
3137     
3138      <p><a name="bc_uv_t"></a><b>bc_uv_t</b></p>
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149      </td>
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160      <td style="vertical-align: top;">C * 20</td>
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182      <td style="vertical-align: top;">
3183     
3184     
3185     
3186     
3187     
3188     
3189     
3190     
3191     
3192     
3193      <p style="font-style: normal;">Top boundary condition of the
3194horizontal velocity components u and v.&nbsp; </p>
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205     
3206     
3207     
3208     
3209     
3210     
3211     
3212     
3213     
3214     
3215      <p>Allowed values are <span style="font-style: italic;">'dirichlet'</span>
3216and <span style="font-style: italic;">'neumann'</span>. The
3217Dirichlet condition yields u(k=nz+1) = ug(nz+1) and v(k=nz+1) =
3218vg(nz+1),
3219Neumann condition yields the free-slip condition with u(k=nz+1) =
3220u(k=nz) and v(k=nz+1) = v(k=nz) (up to k=nz the prognostic equations
3221for the velocities are solved).</p>
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232      </td>
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243    </tr>
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254    <tr>
3255
3256
3257
3258
3259
3260
3261      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_height"></a>building_height</span></td>
3262
3263
3264
3265
3266
3267
3268      <td style="vertical-align: top;">R</td>
3269
3270
3271
3272
3273
3274
3275      <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
3276
3277
3278
3279
3280
3281
3282      <td>Height of a single building in m.<br>
3283
3284
3285
3286
3287
3288
3289      <br>
3290
3291
3292
3293
3294
3295
3296      <span style="font-weight: bold;">building_height</span> must be less than the height of the model domain. This parameter requires the use of&nbsp;<a href="#topography">topography</a> = <span style="font-style: italic;">'single_building'</span>.</td>
3297
3298
3299
3300
3301
3302
3303    </tr>
3304
3305
3306
3307
3308
3309
3310    <tr>
3311
3312
3313
3314
3315
3316
3317      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_x"></a>building_length_x</span></td>
3318
3319
3320
3321
3322
3323
3324      <td style="vertical-align: top;">R</td>
3325
3326
3327
3328
3329
3330
3331      <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
3332
3333
3334
3335
3336
3337
3338      <td><span style="font-style: italic;"></span>Width of a single building in m.<br>
3339
3340
3341
3342
3343
3344
3345      <br>
3346
3347
3348
3349
3350
3351
3352Currently, <span style="font-weight: bold;">building_length_x</span> must be at least <span style="font-style: italic;">3 *&nbsp;</span><a style="font-style: italic;" href="#dx">dx</a> and no more than <span style="font-style: italic;">(&nbsp;</span><a style="font-style: italic;" href="#nx">nx</a><span style="font-style: italic;"> - 1 ) </span><span style="font-style: italic;"> * <a href="#dx">dx</a> </span><span style="font-style: italic;">- <a href="#building_wall_left">building_wall_left</a><a href="#dx"></a><a href="#dx"></a></span>. This parameter requires the use of&nbsp;<a href="#topography">topography</a> = <span style="font-style: italic;">'single_building'</span>.</td>
3353
3354
3355
3356
3357
3358
3359    </tr>
3360
3361
3362
3363
3364
3365
3366    <tr>
3367
3368
3369
3370
3371
3372
3373      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_y"></a>building_length_y</span></td>
3374
3375
3376
3377
3378
3379
3380      <td style="vertical-align: top;">R</td>
3381
3382
3383
3384
3385
3386
3387      <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
3388
3389
3390
3391
3392
3393
3394      <td>Depth of a single building in m.<br>
3395
3396
3397
3398
3399
3400
3401      <br>
3402
3403
3404
3405
3406
3407
3408Currently, <span style="font-weight: bold;">building_length_y</span> must be at least <span style="font-style: italic;">3 *&nbsp;</span><a style="font-style: italic;" href="#dy">dy</a> and no more than <span style="font-style: italic;">(&nbsp;</span><a style="font-style: italic;" href="#ny">ny</a><span style="font-style: italic;"> - 1 )&nbsp;</span><span style="font-style: italic;"> * <a href="#dy">dy</a></span><span style="font-style: italic;"> - <a href="#building_wall_south">building_wall_south</a><a href="#dy"></a></span>. This parameter requires the use of&nbsp;<a href="#topography">topography</a> = <span style="font-style: italic;">'single_building'</span>.</td>
3409
3410
3411
3412
3413
3414
3415    </tr>
3416
3417
3418
3419
3420
3421
3422    <tr>
3423
3424
3425
3426
3427
3428
3429      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_left"></a>building_wall_left</span></td>
3430
3431
3432
3433
3434
3435
3436      <td style="vertical-align: top;">R</td>
3437
3438
3439
3440
3441
3442
3443      <td style="vertical-align: top;"><span style="font-style: italic;">building centered in x-direction</span></td>
3444
3445
3446
3447
3448
3449
3450      <td>x-coordinate of the left building wall (distance between the left building wall and the left border of the model domain) in m.<br>
3451
3452
3453
3454
3455
3456
3457      <br>
3458
3459
3460
3461
3462
3463
3464Currently, <span style="font-weight: bold;">building_wall_left</span> must be at least <span style="font-style: italic;">1 *&nbsp;</span><a style="font-style: italic;" href="#dx">dx</a> and less than <span style="font-style: italic;">( <a href="#nx">nx</a>&nbsp; - 1 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a></span>. This parameter requires the use of&nbsp;<a href="#topography">topography</a> = <span style="font-style: italic;">'single_building'</span>.<br>
3465
3466
3467
3468
3469
3470
3471      <br>
3472
3473
3474
3475
3476
3477
3478The default value&nbsp;<span style="font-weight: bold;">building_wall_left</span> = <span style="font-style: italic;">( ( <a href="#nx">nx</a>&nbsp;+ 1 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a> ) / 2</span> centers the building in x-direction. </td>
3479
3480
3481
3482
3483
3484
3485    </tr>
3486
3487
3488
3489
3490
3491
3492    <tr>
3493
3494
3495
3496
3497
3498
3499      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_south"></a>building_wall_south</span></td>
3500
3501
3502
3503
3504
3505
3506      <td style="vertical-align: top;">R</td>
3507
3508
3509
3510
3511
3512
3513      <td style="vertical-align: top;"><span style="font-style: italic;"></span><span style="font-style: italic;">building centered in y-direction</span></td>
3514
3515
3516
3517
3518
3519
3520      <td>y-coordinate of the South building wall (distance between the
3521South building wall and the South border of the model domain) in m.<br>
3522
3523
3524
3525
3526
3527
3528      <br>
3529
3530
3531
3532
3533
3534
3535Currently, <span style="font-weight: bold;">building_wall_south</span> must be at least <span style="font-style: italic;">1 *&nbsp;</span><a style="font-style: italic;" href="#dy">dy</a> and less than <span style="font-style: italic;">( <a href="#ny">ny</a>&nbsp; - 1 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a></span>. This parameter requires the use of&nbsp;<a href="#topography">topography</a> = <span style="font-style: italic;">'single_building'</span>.<br>
3536
3537
3538
3539
3540
3541
3542      <br>
3543
3544
3545
3546
3547
3548
3549The default value&nbsp;<span style="font-weight: bold;">building_wall_south</span> = <span style="font-style: italic;">( ( <a href="#ny">ny</a>&nbsp;+ 1 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a> ) / 2</span> centers the building in y-direction. </td>
3550
3551
3552
3553
3554
3555
3556    </tr>
3557
3558
3559
3560
3561
3562
3563    <tr>
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="cloud_droplets"></a>cloud_droplets</span><br>
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585      </td>
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596      <td style="vertical-align: top;">L<br>
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607      </td>
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span><br>
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629      </td>
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640      <td style="vertical-align: top;">Parameter to switch on usage of cloud droplets.<br>
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651      <br>
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662Cloud droplets require to use the particle package (<span style="font-weight: bold;">mrun</span>-option <span style="font-family: monospace;">-p particles</span>),
3663so in this case a particle corresponds to a droplet. The droplet
3664features (number of droplets, initial radius, etc.) can be steered with
3665the&nbsp; respective particle parameters (see e.g. <a href="#chapter_4.2.html#radius">radius</a>).
3666The real number of initial droplets in a grid cell is equal to the
3667initial number of droplets (defined by the particle source parameters <span lang="en-GB"><font face="Thorndale, serif"> </font></span><a href="chapter_4.2.html#pst"><span lang="en-GB"><font face="Thorndale, serif">pst</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psl"><span lang="en-GB"><font face="Thorndale, serif">psl</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psr"><span lang="en-GB"><font face="Thorndale, serif">psr</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pss"><span lang="en-GB"><font face="Thorndale, serif">pss</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psn"><span lang="en-GB"><font face="Thorndale, serif">psn</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#psb"><span lang="en-GB"><font face="Thorndale, serif">psb</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pdx"><span lang="en-GB"><font face="Thorndale, serif">pdx</font></span></a><span lang="en-GB"><font face="Thorndale, serif">, </font></span><a href="chapter_4.2.html#pdy"><span lang="en-GB"><font face="Thorndale, serif">pdy</font></span></a>
3668      <span lang="en-GB"><font face="Thorndale, serif">and </font></span><a href="chapter_4.2.html#pdz"><span lang="en-GB"><font face="Thorndale, serif">pdz</font></span></a><span lang="en-GB"></span><span lang="en-GB"></span>) times the <a href="#initial_weighting_factor">initial_weighting_factor</a>.<br>
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679      <br>
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690In case of using cloud droplets, the default condensation scheme in PALM cannot be used, i.e. <a href="#cloud_physics">cloud_physics</a> must be set <span style="font-style: italic;">.F.</span>.<br>
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701      </td>
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712    </tr>
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723    <tr>
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734      <td style="vertical-align: top;">
3735     
3736     
3737     
3738     
3739     
3740     
3741     
3742     
3743     
3744     
3745      <p><a name="cloud_physics"></a><b>cloud_physics</b></p>
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756      </td>
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767      <td style="vertical-align: top;">L<br>
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778      </td>
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800      <td style="vertical-align: top;">
3801     
3802     
3803     
3804     
3805     
3806     
3807     
3808     
3809     
3810     
3811      <p>Parameter to switch on the condensation scheme.&nbsp; </p>
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822For <b>cloud_physics =</b> <span style="font-style: italic;">.TRUE.</span>, equations for the
3823liquid water&nbsp;
3824content and the liquid water potential temperature are solved instead
3825of those for specific humidity and potential temperature. Note
3826that a grid volume is assumed to be either completely saturated or
3827completely
3828unsaturated (0%-or-100%-scheme). A simple precipitation scheme can
3829additionally be switched on with parameter <a href="#precipitation">precipitation</a>.
3830Also cloud-top cooling by longwave radiation can be utilized (see <a href="#radiation">radiation</a>)<br>
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841      <b><br>
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852cloud_physics =</b> <span style="font-style: italic;">.TRUE. </span>requires <a href="#moisture">moisture</a> =<span style="font-style: italic;"> .TRUE.</span> .<br>
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863Detailed information about the condensation scheme is given in the
3864description of the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM-1/Dokumentationen/Cloud_physics/wolken.pdf">cloud
3865physics module</a> (pdf-file, only in German).<br>
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876      <br>
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887This condensation scheme is not allowed if cloud droplets are simulated explicitly (see <a href="#cloud_droplets">cloud_droplets</a>).<br>
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898      </td>
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909    </tr>
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920    <tr>
3921
3922
3923
3924
3925
3926
3927
3928      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="conserve_volume_flow"></a>conserve_volume_flow</span></td>
3929
3930
3931
3932
3933
3934
3935
3936      <td style="vertical-align: top;">L</td>
3937
3938
3939
3940
3941
3942
3943
3944      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
3945
3946
3947
3948
3949
3950
3951
3952      <td>Conservation of volume flow in x- and y-direction.<br>
3953      <br>
3954      <span style="font-weight: bold;">conserve_volume_flow</span> = <span style="font-style: italic;">.TRUE.</span>
3955guarantees that the volume flow through the xz- or yz-cross-section of
3956the total model domain remains constant (equal to the initial value at
3957t=0) throughout the run.<br>
3958</td>
3959
3960
3961
3962
3963
3964
3965
3966    </tr>
3967
3968
3969
3970
3971
3972
3973
3974    <tr>
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985      <td style="vertical-align: top;">
3986     
3987     
3988     
3989     
3990     
3991     
3992     
3993     
3994     
3995     
3996      <p><a name="cut_spline_overshoot"></a><b>cut_spline_overshoot</b></p>
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007      </td>
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018      <td style="vertical-align: top;">L</td>
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029      <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span></td>
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040      <td style="vertical-align: top;">
4041     
4042     
4043     
4044     
4045     
4046     
4047     
4048     
4049     
4050     
4051      <p>Cuts off of so-called overshoots, which can occur with the
4052upstream-spline scheme.&nbsp; </p>
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063     
4064     
4065     
4066     
4067     
4068     
4069     
4070     
4071     
4072     
4073      <p><font color="#000000">The cubic splines tend to overshoot in
4074case of discontinuous changes of variables between neighbouring grid
4075points.</font><font color="#ff0000"> </font><font color="#000000">This
4076may lead to errors in calculating the advection tendency.</font> Choice
4077of <b>cut_spline_overshoot</b> = <i>.TRUE.</i> (switched on by
4078default)
4079allows variable values not to exceed an interval defined by the
4080respective adjacent grid points. This interval can be adjusted
4081seperately for every prognostic variable (see initialization parameters
4082      <a href="#overshoot_limit_e">overshoot_limit_e</a>, <a href="#overshoot_limit_pt">overshoot_limit_pt</a>, <a href="#overshoot_limit_u">overshoot_limit_u</a>,
4083etc.). This might be necessary in case that the
4084default interval has a non-tolerable effect on the model
4085results.&nbsp; </p>
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096     
4097     
4098     
4099     
4100     
4101     
4102     
4103     
4104     
4105     
4106      <p>Overshoots may also be removed using the parameters <a href="#ups_limit_e">ups_limit_e</a>, <a href="#ups_limit_pt">ups_limit_pt</a>,
4107etc. as well as by applying a long-filter (see <a href="#long_filter_factor">long_filter_factor</a>).</p>
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118      </td>
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129    </tr>
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140    <tr>
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151      <td style="vertical-align: top;">
4152     
4153     
4154     
4155     
4156     
4157     
4158     
4159     
4160     
4161     
4162      <p><a name="damp_level_1d"></a><b>damp_level_1d</b></p>
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173      </td>
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184      <td style="vertical-align: top;">R</td>
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195      <td style="vertical-align: top;"><span style="font-style: italic;">zu(nz+1)</span></td>
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206      <td style="vertical-align: top;">
4207     
4208     
4209     
4210     
4211     
4212     
4213     
4214     
4215     
4216     
4217      <p>Height where the damping layer begins in the 1d-model
4218(in m).&nbsp; </p>
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229     
4230     
4231     
4232     
4233     
4234     
4235     
4236     
4237     
4238     
4239      <p>This parameter is used to switch on a damping layer for the
42401d-model, which is generally needed for the damping of inertia
4241oscillations. Damping is done by gradually increasing the value
4242of the eddy diffusivities about 10% per vertical grid level
4243(starting with the value at the height given by <b>damp_level_1d</b>,
4244or possibly from the next grid pint above), i.e. K<sub>m</sub>(k+1) =
42451.1 * K<sub>m</sub>(k).
4246The values of K<sub>m</sub> are limited to 10 m**2/s at maximum.&nbsp; <br>
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257This parameter only comes into effect if the 1d-model is switched on
4258for
4259the initialization of the 3d-model using <a href="#initializing_actions">initializing_actions</a>
4260= <span style="font-style: italic;">'set_1d-model_profiles'</span>. <br>
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271      </p>
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282      </td>
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293    </tr>
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304    <tr>
4305      <td style="vertical-align: top;"><a name="dissipation_1d"></a><span style="font-weight: bold;">dissipation_1d</span><br>
4306      </td>
4307      <td style="vertical-align: top;">C*20<br>
4308      </td>
4309      <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
4310      <span style="font-style: italic;">model'</span><br>
4311      </td>
4312      <td style="vertical-align: top;">Calculation method for the energy dissipation term in the TKE equation of the 1d-model.<br>
4313      <br>
4314By default the dissipation is calculated as in the 3d-model using diss = (0.19 + 0.74 * l / l_grid) * e**1.5 / l.<br>
4315      <br>
4316Setting <span style="font-weight: bold;">dissipation_1d</span> = <span style="font-style: italic;">'detering'</span> forces the dissipation to be calculated as diss = 0.064 * e**1.5 / l.<br>
4317      </td>
4318    </tr>
4319<tr>
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330      <td style="vertical-align: top;">
4331     
4332     
4333     
4334     
4335     
4336     
4337     
4338     
4339     
4340     
4341      <p><a name="dt"></a><b>dt</b></p>
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352      </td>
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363      <td style="vertical-align: top;">R</td>
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374      <td style="vertical-align: top;"><span style="font-style: italic;">variable</span></td>
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385      <td style="vertical-align: top;">
4386     
4387     
4388     
4389     
4390     
4391     
4392     
4393     
4394     
4395     
4396      <p>Time step for the 3d-model (in s).&nbsp; </p>
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407     
4408     
4409     
4410     
4411     
4412     
4413     
4414     
4415     
4416     
4417      <p>By default, (i.e. if a Runge-Kutta scheme is used, see <a href="#timestep_scheme">timestep_scheme</a>)
4418the value of the time step is calculating after each time step
4419(following the time step criteria) and
4420used for the next step.</p>
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431     
4432     
4433     
4434     
4435     
4436     
4437     
4438     
4439     
4440     
4441      <p>If the user assigns <b>dt</b> a value, then the time step is
4442fixed to this value throughout the whole run (whether it fulfills the
4443time step
4444criteria or not). However, changes are allowed for restart runs,
4445because <b>dt</b> can also be used as a <a href="chapter_4.2.html#dt_laufparameter">run
4446parameter</a>.&nbsp; </p>
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457     
4458     
4459     
4460     
4461     
4462     
4463     
4464     
4465     
4466     
4467      <p>In case that the calculated time step meets the condition<br>
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478      </p>
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489     
4490     
4491     
4492     
4493     
4494     
4495     
4496     
4497     
4498     
4499      <ul>
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510       
4511       
4512       
4513       
4514       
4515       
4516       
4517       
4518       
4519       
4520        <p><b>dt</b> &lt; 0.00001 * dt_max (with dt_max = 20.0)</p>
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531     
4532     
4533     
4534     
4535     
4536     
4537     
4538     
4539     
4540     
4541      </ul>
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552     
4553     
4554     
4555     
4556     
4557     
4558     
4559     
4560     
4561     
4562      <p>the simulation will be aborted. Such situations usually arise
4563in case of any numerical problem / instability which causes a
4564non-realistic increase of the wind speed.&nbsp; </p>
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575     
4576     
4577     
4578     
4579     
4580     
4581     
4582     
4583     
4584     
4585      <p>A small time step due to a large mean horizontal windspeed
4586speed may be enlarged by using a coordinate transformation (see <a href="#galilei_transformation">galilei_transformation</a>),
4587in order to spare CPU time.<br>
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598      </p>
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609     
4610     
4611     
4612     
4613     
4614     
4615     
4616     
4617     
4618     
4619      <p>If the leapfrog timestep scheme is used (see <a href="#timestep_scheme">timestep_scheme</a>)
4620a temporary time step value dt_new is calculated first, with dt_new = <a href="chapter_4.2.html#fcl_factor">cfl_factor</a>
4621* dt_crit where dt_crit is the maximum timestep allowed by the CFL and
4622diffusion condition. Next it is examined whether dt_new exceeds or
4623falls below the
4624value of the previous timestep by at
4625least +5 % / -2%. If it is smaller, <span style="font-weight: bold;">dt</span>
4626= dt_new is immediately used for the next timestep. If it is larger,
4627then <span style="font-weight: bold;">dt </span>= 1.02 * dt_prev
4628(previous timestep) is used as the new timestep, however the time
4629step is only increased if the last change of the time step is dated
4630back at
4631least 30 iterations. If dt_new is located in the interval mentioned
4632above, then dt
4633does not change at all. By doing so, permanent time step changes as
4634well as large
4635sudden changes (increases) in the time step are avoided.</p>
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646      </td>
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657    </tr>
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668    <tr>
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679      <td style="vertical-align: top;">
4680     
4681     
4682     
4683     
4684     
4685     
4686     
4687     
4688     
4689     
4690      <p><a name="dt_pr_1d"></a><b>dt_pr_1d</b></p>
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701      </td>
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712      <td style="vertical-align: top;">R</td>
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734      <td style="vertical-align: top;">
4735     
4736     
4737     
4738     
4739     
4740     
4741     
4742     
4743     
4744     
4745      <p>Temporal interval of vertical profile output of the 1D-model
4746(in s).&nbsp; </p>
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757     
4758     
4759     
4760     
4761     
4762     
4763     
4764     
4765     
4766     
4767      <p>Data are written in ASCII format to file <a href="chapter_3.4.html#LIST_PROFIL_1D">LIST_PROFIL_1D</a>.
4768This parameter is only in effect if the 1d-model has been switched on
4769for the
4770initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4771= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782      </td>
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793    </tr>
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804    <tr>
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815      <td style="vertical-align: top;">
4816     
4817     
4818     
4819     
4820     
4821     
4822     
4823     
4824     
4825     
4826      <p><a name="dt_run_control_1d"></a><b>dt_run_control_1d</b></p>
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837      </td>
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848      <td style="vertical-align: top;">R</td>
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859      <td style="vertical-align: top;"><span style="font-style: italic;">60.0</span></td>
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870      <td style="vertical-align: top;">
4871     
4872     
4873     
4874     
4875     
4876     
4877     
4878     
4879     
4880     
4881      <p>Temporal interval of runtime control output of the 1d-model
4882(in s).&nbsp; </p>
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893     
4894     
4895     
4896     
4897     
4898     
4899     
4900     
4901     
4902     
4903      <p>Data are written in ASCII format to file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
4904This parameter is only in effect if the 1d-model is switched on for the
4905initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4906= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917      </td>
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928    </tr>
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939    <tr>
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950      <td style="vertical-align: top;">
4951     
4952     
4953     
4954     
4955     
4956     
4957     
4958     
4959     
4960     
4961      <p><a name="dx"></a><b>dx</b></p>
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972      </td>
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983      <td style="vertical-align: top;">R</td>
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005      <td style="vertical-align: top;">
5006     
5007     
5008     
5009     
5010     
5011     
5012     
5013     
5014     
5015     
5016      <p>Horizontal grid spacing along the x-direction (in m).&nbsp; </p>
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027     
5028     
5029     
5030     
5031     
5032     
5033     
5034     
5035     
5036     
5037      <p>Along x-direction only a constant grid spacing is allowed.</p>
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048      </td>
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059    </tr>
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070    <tr>
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081      <td style="vertical-align: top;">
5082     
5083     
5084     
5085     
5086     
5087     
5088     
5089     
5090     
5091     
5092      <p><a name="dy"></a><b>dy</b></p>
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103      </td>
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114      <td style="vertical-align: top;">R</td>
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136      <td style="vertical-align: top;">
5137     
5138     
5139     
5140     
5141     
5142     
5143     
5144     
5145     
5146     
5147      <p>Horizontal grid spacing along the x-direction (in m).&nbsp; </p>
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158     
5159     
5160     
5161     
5162     
5163     
5164     
5165     
5166     
5167     
5168      <p>Along x-direction only a constant grid spacing is allowed.</p>
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179      </td>
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190    </tr>
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201    <tr>
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212      <td style="vertical-align: top;">
5213     
5214     
5215     
5216     
5217     
5218     
5219     
5220     
5221     
5222     
5223      <p><a name="dz"></a><b>dz</b></p>
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234      </td>
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245      <td style="vertical-align: top;">R</td>
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256      <td style="vertical-align: top;"><br>
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267      </td>
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278      <td style="vertical-align: top;">
5279     
5280     
5281     
5282     
5283     
5284     
5285     
5286     
5287     
5288     
5289      <p>Vertical grid spacing (in m).&nbsp; </p>
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300     
5301     
5302     
5303     
5304     
5305     
5306     
5307     
5308     
5309     
5310      <p>This parameter must be assigned by the user, because no
5311default value is given.<br>
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322      </p>
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333     
5334     
5335     
5336     
5337     
5338     
5339     
5340     
5341     
5342     
5343      <p>By default, the
5344model uses constant grid spacing along z-direction, but it can be
5345stretched using the parameters <a href="#dz_stretch_level">dz_stretch_level</a>
5346and <a href="#dz_stretch_factor">dz_stretch_factor</a>. In case of stretching, a maximum allowed grid spacing can be given by <a href="#dz_max">dz_max</a>.<br>
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357      </p>
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368     
5369     
5370     
5371     
5372     
5373     
5374     
5375     
5376     
5377     
5378      <p>Assuming a constant <span style="font-weight: bold;">dz</span>,
5379the scalar levels (zu) are calculated directly by:&nbsp; </p>
5380
5381
5382
5383
5384
5385
5386
5387
5388
5389
5390     
5391     
5392     
5393     
5394     
5395     
5396     
5397     
5398     
5399     
5400      <ul>
5401
5402
5403
5404
5405
5406
5407
5408
5409
5410
5411       
5412       
5413       
5414       
5415       
5416       
5417       
5418       
5419       
5420       
5421        <p>zu(0) = - dz * 0.5&nbsp; <br>
5422
5423
5424
5425
5426
5427
5428
5429
5430
5431
5432zu(1) = dz * 0.5</p>
5433
5434
5435
5436
5437
5438
5439
5440
5441
5442
5443     
5444     
5445     
5446     
5447     
5448     
5449     
5450     
5451     
5452     
5453      </ul>
5454
5455
5456
5457
5458
5459
5460
5461
5462
5463
5464     
5465     
5466     
5467     
5468     
5469     
5470     
5471     
5472     
5473     
5474      <p>The w-levels lie
5475half between them:&nbsp; </p>
5476
5477
5478
5479
5480
5481
5482
5483
5484
5485
5486     
5487     
5488     
5489     
5490     
5491     
5492     
5493     
5494     
5495     
5496      <ul>
5497
5498
5499
5500
5501
5502
5503
5504
5505
5506
5507       
5508       
5509       
5510       
5511       
5512       
5513       
5514       
5515       
5516       
5517        <p>zw(k) = ( zu(k) + zu(k+1) ) * 0.5</p>
5518
5519
5520
5521
5522
5523
5524
5525
5526
5527
5528     
5529     
5530     
5531     
5532     
5533     
5534     
5535     
5536     
5537     
5538      </ul>
5539
5540
5541
5542
5543
5544
5545
5546
5547
5548
5549      </td>
5550
5551
5552
5553
5554
5555
5556
5557
5558
5559
5560    </tr>
5561
5562
5563
5564
5565
5566
5567
5568
5569
5570
5571    <tr><td style="vertical-align: top;"><a name="dz_max"></a><span style="font-weight: bold;">dz_max</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td><td style="vertical-align: top;">Allowed maximum vertical grid spacing (in m).<br><br>If the vertical grid is stretched (see <a href="#dz_stretch_factor">dz_stretch_factor</a> and <a href="#dz_stretch_level">dz_stretch_level</a>), <span style="font-weight: bold;">dz_max</span> can be used to limit the vertical grid spacing.</td></tr><tr>
5572
5573
5574
5575
5576
5577
5578
5579
5580
5581
5582      <td style="vertical-align: top;">
5583     
5584     
5585     
5586     
5587     
5588     
5589     
5590     
5591     
5592     
5593      <p><a name="dz_stretch_factor"></a><b>dz_stretch_factor</b></p>
5594
5595
5596
5597
5598
5599
5600
5601
5602
5603
5604      </td>
5605
5606
5607
5608
5609
5610
5611
5612
5613
5614
5615      <td style="vertical-align: top;">R</td>
5616
5617
5618
5619
5620
5621
5622
5623
5624
5625
5626      <td style="vertical-align: top;"><span style="font-style: italic;">1.08</span></td>
5627
5628
5629
5630
5631
5632
5633
5634
5635
5636
5637      <td style="vertical-align: top;">
5638     
5639     
5640     
5641     
5642     
5643     
5644     
5645     
5646     
5647     
5648      <p>Stretch factor for a vertically stretched grid (see <a href="#dz_stretch_level">dz_stretch_level</a>).&nbsp; </p>
5649
5650
5651
5652
5653
5654
5655
5656
5657
5658
5659     
5660     
5661     
5662     
5663     
5664     
5665     
5666     
5667     
5668     
5669      <p>The stretch factor should not exceed a value of approx. 1.10 -
56701.12, otherwise the discretization errors due to the stretched grid not
5671negligible any more. (refer Kalnay de Rivas)</p>
5672
5673
5674
5675
5676
5677
5678
5679
5680
5681
5682      </td>
5683
5684
5685
5686
5687
5688
5689
5690
5691
5692
5693    </tr>
5694
5695
5696
5697
5698
5699
5700
5701
5702
5703
5704    <tr>
5705
5706
5707
5708
5709
5710
5711
5712
5713
5714
5715      <td style="vertical-align: top;">
5716     
5717     
5718     
5719     
5720     
5721     
5722     
5723     
5724     
5725     
5726      <p><a name="dz_stretch_level"></a><b>dz_stretch_level</b></p>
5727
5728
5729
5730
5731
5732
5733
5734
5735
5736
5737      </td>
5738
5739
5740
5741
5742
5743
5744
5745
5746
5747
5748      <td style="vertical-align: top;">R</td>
5749
5750
5751
5752
5753
5754
5755
5756
5757
5758
5759      <td style="vertical-align: top;"><span style="font-style: italic;">100000.0</span><br>
5760
5761
5762
5763
5764
5765
5766
5767
5768
5769
5770      </td>
5771
5772
5773
5774
5775
5776
5777
5778
5779
5780
5781      <td style="vertical-align: top;">
5782     
5783     
5784     
5785     
5786     
5787     
5788     
5789     
5790     
5791     
5792      <p>Height level above which the grid is to be stretched
5793vertically (in m).&nbsp; </p>
5794
5795
5796
5797
5798
5799
5800
5801
5802
5803
5804     
5805     
5806     
5807     
5808     
5809     
5810     
5811     
5812     
5813     
5814      <p>The vertical grid spacings <a href="#dz">dz</a>
5815above this level are calculated as&nbsp; </p>
5816
5817
5818
5819
5820
5821
5822
5823
5824
5825
5826     
5827     
5828     
5829     
5830     
5831     
5832     
5833     
5834     
5835     
5836      <ul>
5837
5838
5839
5840
5841
5842
5843
5844
5845
5846
5847       
5848       
5849       
5850       
5851       
5852       
5853       
5854       
5855       
5856       
5857        <p><b>dz</b>(k+1) = <b>dz</b>(k) * <a href="#dz_stretch_factor">dz_stretch_factor</a></p>
5858
5859
5860
5861
5862
5863
5864
5865
5866
5867
5868     
5869     
5870     
5871     
5872     
5873     
5874     
5875     
5876     
5877     
5878      </ul>
5879
5880
5881
5882
5883
5884
5885
5886
5887
5888
5889     
5890     
5891     
5892     
5893     
5894     
5895     
5896     
5897     
5898     
5899      <p>and used as spacings for the scalar levels (zu). The
5900w-levels are then defined as:&nbsp; </p>
5901
5902
5903
5904
5905
5906
5907
5908
5909
5910
5911     
5912     
5913     
5914     
5915     
5916     
5917     
5918     
5919     
5920     
5921      <ul>
5922
5923
5924
5925
5926
5927
5928
5929
5930
5931
5932       
5933       
5934       
5935       
5936       
5937       
5938       
5939       
5940       
5941       
5942        <p>zw(k) = ( zu(k) + zu(k+1) ) * 0.5</p>
5943
5944
5945
5946
5947
5948
5949
5950
5951
5952
5953     
5954     
5955     
5956     
5957     
5958     
5959     
5960     
5961     
5962     
5963      </ul>
5964
5965
5966
5967
5968
5969
5970
5971
5972
5973
5974      </td>
5975
5976
5977
5978
5979
5980
5981
5982
5983
5984
5985    </tr>
5986
5987
5988
5989
5990
5991
5992
5993
5994
5995
5996    <tr>
5997
5998
5999
6000
6001
6002
6003
6004      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_min"></a>e_min</span></td>
6005
6006
6007
6008
6009
6010
6011
6012      <td style="vertical-align: top;">R</td>
6013
6014
6015
6016
6017
6018
6019
6020      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
6021
6022
6023
6024
6025
6026
6027
6028      <td>Minimum subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
6029
6030
6031
6032
6033
6034
6035
6036      <br>This
6037option&nbsp;adds artificial viscosity to the flow by ensuring that the
6038subgrid-scale TKE does not fall below the minimum threshold <span style="font-weight: bold;">e_min</span>.</td>
6039
6040
6041
6042
6043
6044
6045
6046    </tr>
6047
6048
6049
6050
6051
6052
6053
6054    <tr>
6055
6056
6057
6058
6059
6060
6061
6062
6063
6064
6065      <td style="vertical-align: top;">
6066     
6067     
6068     
6069     
6070     
6071     
6072     
6073     
6074     
6075     
6076      <p><a name="end_time_1d"></a><b>end_time_1d</b></p>
6077
6078
6079
6080
6081
6082
6083
6084
6085
6086
6087      </td>
6088
6089
6090
6091
6092
6093
6094
6095
6096
6097
6098      <td style="vertical-align: top;">R</td>
6099
6100
6101
6102
6103
6104
6105
6106
6107
6108
6109      <td style="vertical-align: top;"><span style="font-style: italic;">864000.0</span><br>
6110
6111
6112
6113
6114
6115
6116
6117
6118
6119
6120      </td>
6121
6122
6123
6124
6125
6126
6127
6128
6129
6130
6131      <td style="vertical-align: top;">
6132     
6133     
6134     
6135     
6136     
6137     
6138     
6139     
6140     
6141     
6142      <p>Time to be simulated for the 1d-model (in s).&nbsp; </p>
6143
6144
6145
6146
6147
6148
6149
6150
6151
6152
6153     
6154     
6155     
6156     
6157     
6158     
6159     
6160     
6161     
6162     
6163      <p>The default value corresponds to a simulated time of 10 days.
6164Usually, after such a period the inertia oscillations have completely
6165decayed and the solution of the 1d-model can be regarded as stationary
6166(see <a href="#damp_level_1d">damp_level_1d</a>).
6167This parameter is only in effect if the 1d-model is switched on for the
6168initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
6169= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
6170
6171
6172
6173
6174
6175
6176
6177
6178
6179
6180      </td>
6181
6182
6183
6184
6185
6186
6187
6188
6189
6190
6191    </tr>
6192
6193
6194
6195
6196
6197
6198
6199
6200
6201
6202    <tr>
6203
6204
6205
6206
6207
6208
6209
6210
6211
6212
6213      <td style="vertical-align: top;">
6214     
6215     
6216     
6217     
6218     
6219     
6220     
6221     
6222     
6223     
6224      <p><a name="fft_method"></a><b>fft_method</b></p>
6225
6226
6227
6228
6229
6230
6231
6232
6233
6234
6235      </td>
6236
6237
6238
6239
6240
6241
6242
6243
6244
6245
6246      <td style="vertical-align: top;">C * 20</td>
6247
6248
6249
6250
6251
6252
6253
6254
6255
6256
6257      <td style="vertical-align: top;"><span style="font-style: italic;">'system-</span><br style="font-style: italic;">
6258
6259
6260
6261
6262
6263
6264
6265
6266
6267
6268      <span style="font-style: italic;">specific'</span></td>
6269
6270
6271
6272
6273
6274
6275
6276
6277
6278
6279      <td style="vertical-align: top;">
6280     
6281     
6282     
6283     
6284     
6285     
6286     
6287     
6288     
6289     
6290      <p>FFT-method to be used.<br>
6291
6292
6293
6294
6295
6296
6297
6298
6299
6300
6301      </p>
6302
6303
6304
6305
6306
6307
6308
6309
6310
6311
6312     
6313     
6314     
6315     
6316     
6317     
6318     
6319     
6320     
6321     
6322      <p><br>
6323
6324
6325
6326
6327
6328
6329
6330
6331
6332
6333The fast fourier transformation (FFT) is used for solving the
6334perturbation pressure equation with a direct method (see <a href="chapter_4.2.html#psolver">psolver</a>)
6335and for calculating power spectra (see optional software packages,
6336section <a href="chapter_4.2.html#spectra_package">4.2</a>).</p>
6337
6338
6339
6340
6341
6342
6343
6344
6345
6346
6347     
6348     
6349     
6350     
6351     
6352     
6353     
6354     
6355     
6356     
6357      <p><br>
6358
6359
6360
6361
6362
6363
6364
6365
6366
6367
6368By default, system-specific, optimized routines from external
6369vendor libraries are used. However, these are available only on certain
6370computers and there are more or less severe restrictions concerning the
6371number of gridpoints to be used with them.<br>
6372
6373
6374
6375
6376
6377
6378
6379
6380
6381
6382      </p>
6383
6384
6385
6386
6387
6388
6389
6390
6391
6392
6393     
6394     
6395     
6396     
6397     
6398     
6399     
6400     
6401     
6402     
6403      <p>There are two other PALM internal methods available on every
6404machine (their respective source code is part of the PALM source code):</p>
6405
6406
6407
6408
6409
6410
6411
6412
6413
6414
6415     
6416     
6417     
6418     
6419     
6420     
6421     
6422     
6423     
6424     
6425      <p>1.: The <span style="font-weight: bold;">Temperton</span>-method
6426from Clive Temperton (ECWMF) which is computationally very fast and
6427switched on with <b>fft_method</b> = <span style="font-style: italic;">'temperton-algorithm'</span>.
6428The number of horizontal gridpoints (nx+1, ny+1) to be used with this
6429method must be composed of prime factors 2, 3 and 5.<br>
6430
6431
6432
6433
6434
6435
6436
6437
6438
6439
6440      </p>
6441
6442
6443
6444
6445
6446
6447
6448
6449
6450
64512.: The <span style="font-weight: bold;">Singleton</span>-method
6452which is very slow but has no restrictions concerning the number of
6453gridpoints to be used with, switched on with <b>fft_method</b> = <span style="font-style: italic;">'singleton-algorithm'</span>. </td>
6454
6455
6456
6457
6458
6459
6460
6461
6462
6463
6464    </tr>
6465
6466
6467
6468
6469
6470
6471
6472
6473
6474
6475    <tr>
6476
6477
6478
6479
6480
6481
6482
6483
6484
6485
6486      <td style="vertical-align: top;">
6487     
6488     
6489     
6490     
6491     
6492     
6493     
6494     
6495     
6496     
6497      <p><a name="galilei_transformation"></a><b>galilei_transformation</b></p>
6498
6499
6500
6501
6502
6503
6504
6505
6506
6507
6508      </td>
6509
6510
6511
6512
6513
6514
6515
6516
6517
6518
6519      <td style="vertical-align: top;">L</td>
6520
6521
6522
6523
6524
6525
6526
6527
6528
6529
6530      <td style="vertical-align: top;"><i>.F.</i></td>
6531
6532
6533
6534
6535
6536
6537
6538
6539
6540
6541      <td style="vertical-align: top;">Application of a Galilei-transformation to the
6542coordinate
6543system of the model.<br><p>With <b>galilei_transformation</b> = <i>.T.,</i> a so-called
6544Galilei-transformation is switched on which ensures that the coordinate
6545system of the model is moved along with the geostrophical wind.
6546Alternatively, the model domain can be moved along with the averaged
6547horizontal wind (see <a href="#use_ug_for_galilei_tr">use_ug_for_galilei_tr</a>,
6548this can and will naturally change in time). With this method,
6549numerical inaccuracies of the Piascek - Williams - scheme (concerns in
6550particular the momentum advection) are minimized. Beyond that, in the
6551majority of cases the lower relative velocities in the moved system
6552permit a larger time step (<a href="#dt">dt</a>).
6553Switching the transformation on is only worthwhile if the geostrophical
6554wind (ug, vg)
6555and the averaged horizontal wind clearly deviate from the value 0. In
6556each case, the distance the coordinate system has been moved is written
6557to the file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.&nbsp;
6558      </p>
6559
6560
6561
6562
6563
6564
6565
6566
6567
6568
6569     
6570     
6571     
6572     
6573     
6574     
6575     
6576     
6577     
6578     
6579      <p>Non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
6580and <a href="#bc_ns">bc_ns</a>), the specification of a gestrophic
6581wind that is not constant with height
6582as well as e.g. stationary inhomogeneities at the bottom boundary do
6583not allow the use of this transformation.</p>
6584
6585
6586
6587
6588
6589
6590
6591
6592
6593
6594      </td>
6595
6596
6597
6598
6599
6600
6601
6602
6603
6604
6605    </tr>
6606
6607
6608
6609
6610
6611
6612
6613
6614
6615
6616    <tr>
6617
6618
6619
6620
6621
6622
6623
6624
6625
6626
6627      <td style="vertical-align: top;">
6628     
6629     
6630     
6631     
6632     
6633     
6634     
6635     
6636     
6637     
6638      <p><a name="grid_matching"></a><b>grid_matching</b></p>
6639
6640
6641
6642
6643
6644
6645
6646
6647
6648
6649      </td>
6650
6651
6652
6653
6654
6655
6656
6657
6658
6659
6660      <td style="vertical-align: top;">C * 6</td>
6661
6662
6663
6664
6665
6666
6667
6668
6669
6670
6671      <td style="vertical-align: top;"><span style="font-style: italic;">'match'</span></td>
6672
6673
6674
6675
6676
6677
6678
6679
6680
6681
6682      <td style="vertical-align: top;">Variable to adjust the subdomain
6683sizes in parallel runs.<br>
6684
6685
6686
6687
6688
6689
6690
6691
6692
6693
6694      <br>
6695
6696
6697
6698
6699
6700
6701
6702
6703
6704
6705For <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>,
6706the subdomains are forced to have an identical
6707size on all processors. In this case the processor numbers in the
6708respective directions of the virtual processor net must fulfill certain
6709divisor conditions concerning the grid point numbers in the three
6710directions (see <a href="#nx">nx</a>,
6711      <a href="#ny">ny</a>
6712and <a href="#nz">nz</a>).
6713Advantage of this method is that all PEs bear the same computational
6714load.<br>
6715
6716
6717
6718
6719
6720
6721
6722
6723
6724
6725      <br>
6726
6727
6728
6729
6730
6731
6732
6733
6734
6735
6736There is no such restriction by default, because then smaller
6737subdomains are allowed on those processors which
6738form the right and/or north boundary of the virtual processor grid. On
6739all other processors the subdomains are of same size. Whether smaller
6740subdomains are actually used, depends on the number of processors and
6741the grid point numbers used. Information about the respective settings
6742are given in file <a href="file:///home/raasch/public_html/PALM_group/home/raasch/public_html/PALM_group/doc/app/chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.<br>
6743
6744
6745
6746
6747
6748
6749
6750
6751
6752
6753      <br>
6754
6755
6756
6757
6758
6759
6760
6761
6762
6763
6764When using a multi-grid method for solving the Poisson equation (see <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">psolver</a>)
6765only <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>
6766is allowed.<br>
6767
6768
6769
6770
6771
6772
6773
6774
6775
6776
6777      <br>
6778
6779
6780
6781
6782
6783
6784
6785
6786
6787
6788      <b>Note:</b><br>
6789
6790
6791
6792
6793
6794
6795
6796
6797
6798
6799In some cases for small processor numbers there may be a very bad load
6800balancing among the
6801processors which may reduce the performance of the code.</td>
6802
6803
6804
6805
6806
6807
6808
6809
6810
6811
6812    </tr>
6813
6814
6815
6816
6817
6818
6819
6820
6821
6822
6823    <tr>
6824
6825
6826
6827
6828
6829
6830
6831
6832
6833
6834      <td style="vertical-align: top;"><a name="inflow_disturbance_begin"></a><b>inflow_disturbance_<br>
6835
6836
6837
6838
6839
6840
6841
6842
6843
6844
6845begin</b></td>
6846
6847
6848
6849
6850
6851
6852
6853
6854
6855
6856      <td style="vertical-align: top;">I</td>
6857
6858
6859
6860
6861
6862
6863
6864
6865
6866
6867      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(10,</span><br style="font-style: italic;">
6868
6869
6870
6871
6872
6873
6874
6875
6876
6877
6878      <span style="font-style: italic;">nx/2 or ny/2)</span></td>
6879
6880
6881
6882
6883
6884
6885
6886
6887
6888
6889      <td style="vertical-align: top;">Lower
6890limit of the horizontal range for which random perturbations are to be
6891imposed on the horizontal velocity field (gridpoints).<br>
6892
6893
6894
6895
6896
6897
6898
6899
6900
6901
6902      <br>
6903
6904
6905
6906
6907
6908
6909
6910
6911
6912
6913If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
6914or <a href="#bc_ns">bc_ns</a>),
6915this parameter gives the gridpoint number (counted horizontally from
6916the inflow)&nbsp; from which on perturbations are imposed on the
6917horizontal velocity field. Perturbations must be switched on with
6918parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
6919
6920
6921
6922
6923
6924
6925
6926
6927
6928
6929    </tr>
6930
6931
6932
6933
6934
6935
6936
6937
6938
6939
6940    <tr>
6941
6942
6943
6944
6945
6946
6947
6948
6949
6950
6951      <td style="vertical-align: top;"><a name="inflow_disturbance_end"></a><b>inflow_disturbance_<br>
6952
6953
6954
6955
6956
6957
6958
6959
6960
6961
6962end</b></td>
6963
6964
6965
6966
6967
6968
6969
6970
6971
6972
6973      <td style="vertical-align: top;">I</td>
6974
6975
6976
6977
6978
6979
6980
6981
6982
6983
6984      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(100,</span><br style="font-style: italic;">
6985
6986
6987
6988
6989
6990
6991
6992
6993
6994
6995      <span style="font-style: italic;">3/4*nx or</span><br style="font-style: italic;">
6996
6997
6998
6999
7000
7001
7002
7003
7004
7005
7006      <span style="font-style: italic;">3/4*ny)</span></td>
7007
7008
7009
7010
7011
7012
7013
7014
7015
7016
7017      <td style="vertical-align: top;">Upper
7018limit of the horizontal range for which random perturbations are
7019to be imposed on the horizontal velocity field (gridpoints).<br>
7020
7021
7022
7023
7024
7025
7026
7027
7028
7029
7030      <br>
7031
7032
7033
7034
7035
7036
7037
7038
7039
7040
7041If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
7042or <a href="#bc_ns">bc_ns</a>),
7043this parameter gives the gridpoint number (counted horizontally from
7044the inflow)&nbsp; unto which perturbations are imposed on the
7045horizontal
7046velocity field. Perturbations must be switched on with parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
7047
7048
7049
7050
7051
7052
7053
7054
7055
7056
7057    </tr>
7058
7059
7060
7061
7062
7063
7064
7065
7066
7067
7068    <tr>
7069
7070
7071
7072
7073
7074
7075
7076
7077
7078
7079      <td style="vertical-align: top;">
7080     
7081     
7082     
7083     
7084     
7085     
7086     
7087     
7088     
7089     
7090      <p><a name="initializing_actions"></a><b>initializing_actions</b></p>
7091
7092
7093
7094
7095
7096
7097
7098
7099
7100
7101      </td>
7102
7103
7104
7105
7106
7107
7108
7109
7110
7111
7112      <td style="vertical-align: top;">C * 100</td>
7113
7114
7115
7116
7117
7118
7119
7120
7121
7122
7123      <td style="vertical-align: top;"><br>
7124
7125
7126
7127
7128
7129
7130
7131
7132
7133
7134      </td>
7135
7136
7137
7138
7139
7140
7141
7142
7143
7144
7145      <td style="vertical-align: top;">
7146     
7147     
7148     
7149     
7150     
7151     
7152     
7153     
7154     
7155     
7156      <p style="font-style: normal;">Initialization actions
7157to be carried out.&nbsp; </p>
7158
7159
7160
7161
7162
7163
7164
7165
7166
7167
7168     
7169     
7170     
7171     
7172     
7173     
7174     
7175     
7176     
7177     
7178      <p style="font-style: normal;">This parameter does not have a
7179default value and therefore must be assigned with each model run. For
7180restart runs <b>initializing_actions</b> = <span style="font-style: italic;">'read_restart_data'</span>
7181must be set. For the initial run of a job chain the following values
7182are allowed:&nbsp; </p>
7183
7184
7185
7186
7187
7188
7189
7190
7191
7192
7193     
7194     
7195     
7196     
7197     
7198     
7199     
7200     
7201     
7202     
7203      <p style="font-style: normal;"><span style="font-style: italic;">'set_constant_profiles'</span>
7204      </p>
7205
7206
7207
7208
7209
7210
7211
7212
7213
7214
7215     
7216     
7217     
7218     
7219     
7220     
7221     
7222     
7223     
7224     
7225      <ul>
7226
7227
7228
7229
7230
7231
7232
7233
7234
7235
7236       
7237       
7238       
7239       
7240       
7241       
7242       
7243       
7244       
7245       
7246        <p>A horizontal wind profile consisting of linear sections (see
7247        <a href="#ug_surface">ug_surface</a>, <a href="#ug_vertical_gradient">ug_vertical_gradient</a>, <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a> and <a href="#vg_surface">vg_surface</a>, <a href="#vg_vertical_gradient">vg_vertical_gradient</a>,
7248        <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
7249respectively) as well as a vertical temperature (humidity) profile
7250consisting of
7251linear sections (see <a href="#pt_surface">pt_surface</a>, <a href="#pt_vertical_gradient">pt_vertical_gradient</a>, <a href="#q_surface">q_surface</a>
7252and <a href="#q_vertical_gradient">q_vertical_gradient</a>)
7253are assumed as initial profiles. The subgrid-scale TKE is set to 0 but K<sub>m</sub>
7254and K<sub>h</sub> are set to very small values because otherwise no TKE
7255would be generated.</p>
7256
7257
7258
7259
7260
7261
7262
7263
7264
7265
7266     
7267     
7268     
7269     
7270     
7271     
7272     
7273     
7274     
7275     
7276      </ul>
7277
7278
7279
7280
7281
7282
7283
7284
7285
7286
7287     
7288     
7289     
7290     
7291     
7292     
7293     
7294     
7295     
7296     
7297      <p style="font-style: italic;">'set_1d-model_profiles' </p>
7298
7299
7300
7301
7302
7303
7304
7305
7306
7307
7308     
7309     
7310     
7311     
7312     
7313     
7314     
7315     
7316     
7317     
7318      <ul>
7319
7320
7321
7322
7323
7324
7325
7326
7327
7328
7329       
7330       
7331       
7332       
7333       
7334       
7335       
7336       
7337       
7338       
7339        <p>The arrays of the 3d-model are initialized with the
7340(stationary) solution of the 1d-model. These are the variables e, kh,
7341km, u, v and with Prandtl layer switched on rif, us, usws, vsws. The
7342temperature (humidity) profile consisting of linear sections is set as
7343for 'set_constant_profiles' and assumed as constant in time within the
73441d-model. For steering of the 1d-model a set of parameters with suffix
7345"_1d" (e.g. <a href="#end_time_1d">end_time_1d</a>, <a href="#damp_level_1d">damp_level_1d</a>)
7346is available.</p>
7347
7348
7349
7350
7351
7352
7353
7354
7355
7356
7357     
7358     
7359     
7360     
7361     
7362     
7363     
7364     
7365     
7366     
7367      </ul>
7368
7369
7370
7371
7372
7373
7374
7375
7376
7377
7378     
7379     
7380     
7381     
7382     
7383     
7384     
7385     
7386     
7387     
7388      <p><span style="font-style: italic;">'by_user'</span></p><p style="margin-left: 40px;">The initialization of the arrays of the 3d-model is under complete control of the user and has to be done in routine <a href="chapter_3.5.1.html#user_init_3d_model">user_init_3d_model</a> of the user-interface.<span style="font-style: italic;"></span></p><p><span style="font-style: italic;">'initialize_vortex'</span> </p>
7389
7390
7391
7392
7393
7394
7395
7396
7397
7398
7399     
7400     
7401     
7402     
7403     
7404     
7405     
7406     
7407     
7408     
7409      <div style="margin-left: 40px;">The initial velocity field of the
74103d-model corresponds to a
7411Rankine-vortex with vertical axis. This setting may be used to test
7412advection schemes. Free-slip boundary conditions for u and v (see <a href="#bc_uv_b">bc_uv_b</a>, <a href="#bc_uv_t">bc_uv_t</a>)
7413are necessary. In order not to distort the vortex, an initial
7414horizontal wind profile constant
7415with height is necessary (to be set by <b>initializing_actions</b>
7416= <span style="font-style: italic;">'set_constant_profiles'</span>)
7417and some other conditions have to be met (neutral stratification,
7418diffusion must be
7419switched off, see <a href="#km_constant">km_constant</a>).
7420The center of the vortex is located at jc = (nx+1)/2. It
7421extends from k = 0 to k = nz+1. Its radius is 8 * <a href="#dx">dx</a>
7422and the exponentially decaying part ranges to 32 * <a href="#dx">dx</a>
7423(see init_rankine.f90). </div>
7424
7425
7426
7427
7428
7429
7430
7431
7432
7433
7434     
7435     
7436     
7437     
7438     
7439     
7440     
7441     
7442     
7443     
7444      <p><span style="font-style: italic;">'initialize_ptanom'</span> </p>
7445
7446
7447
7448
7449
7450
7451
7452
7453
7454
7455     
7456     
7457     
7458     
7459     
7460     
7461     
7462     
7463     
7464     
7465      <ul>
7466
7467
7468
7469
7470
7471
7472
7473
7474
7475
7476       
7477       
7478       
7479       
7480       
7481       
7482       
7483       
7484       
7485       
7486        <p>A 2d-Gauss-like shape disturbance (x,y) is added to the
7487initial temperature field with radius 10.0 * <a href="#dx">dx</a>
7488and center at jc = (nx+1)/2. This may be used for tests of scalar
7489advection schemes
7490(see <a href="#scalar_advec">scalar_advec</a>).
7491Such tests require a horizontal wind profile constant with hight and
7492diffusion
7493switched off (see <span style="font-style: italic;">'initialize_vortex'</span>).
7494Additionally, the buoyancy term
7495must be switched of in the equation of motion&nbsp; for w (this
7496requires the user to comment out the call of <span style="font-family: monospace;">buoyancy</span> in the source code of <span style="font-family: monospace;">prognostic_equations.f90</span>).</p>
7497
7498
7499
7500
7501
7502
7503
7504
7505
7506
7507     
7508     
7509     
7510     
7511     
7512     
7513     
7514     
7515     
7516     
7517      </ul>
7518
7519
7520
7521
7522
7523
7524
7525
7526
7527
7528     
7529     
7530     
7531     
7532     
7533     
7534     
7535     
7536     
7537     
7538      <p style="font-style: normal;">Values may be
7539combined, e.g. <b>initializing_actions</b> = <span style="font-style: italic;">'set_constant_profiles
7540initialize_vortex'</span>, but the values of <span style="font-style: italic;">'set_constant_profiles'</span>, <span style="font-style: italic;">'set_1d-model_profiles'</span>
7541, and <span style="font-style: italic;">'by_user'</span> must not be given at the same time.</p>
7542
7543
7544
7545
7546
7547
7548
7549
7550
7551
7552     
7553     
7554     
7555     
7556     
7557     
7558     
7559     
7560     
7561     
7562      <p style="font-style: italic;"> </p>
7563
7564
7565
7566
7567
7568
7569
7570
7571
7572
7573      </td>
7574
7575
7576
7577
7578
7579
7580
7581
7582
7583
7584    </tr>
7585
7586
7587
7588
7589
7590
7591
7592
7593
7594
7595   
7596
7597
7598
7599
7600
7601
7602
7603
7604
7605
7606    <tr>
7607
7608
7609
7610
7611
7612
7613
7614
7615
7616
7617      <td style="vertical-align: top;">
7618     
7619     
7620     
7621     
7622     
7623     
7624     
7625     
7626     
7627     
7628      <p><a name="km_constant"></a><b>km_constant</b></p>
7629
7630
7631
7632
7633
7634
7635
7636
7637
7638
7639      </td>
7640
7641
7642
7643
7644
7645
7646
7647
7648
7649
7650      <td style="vertical-align: top;">R</td>
7651
7652
7653
7654
7655
7656
7657
7658
7659
7660
7661      <td style="vertical-align: top;"><i>variable<br>
7662
7663
7664
7665
7666
7667
7668
7669
7670
7671
7672(computed from TKE)</i></td>
7673
7674
7675
7676
7677
7678
7679
7680
7681
7682
7683      <td style="vertical-align: top;">
7684     
7685     
7686     
7687     
7688     
7689     
7690     
7691     
7692     
7693     
7694      <p>Constant eddy diffusivities are used (laminar
7695simulations).&nbsp; </p>
7696
7697
7698
7699
7700
7701
7702
7703
7704
7705
7706     
7707     
7708     
7709     
7710     
7711     
7712     
7713     
7714     
7715     
7716      <p>If this parameter is specified, both in the 1d and in the
77173d-model constant values for the eddy diffusivities are used in
7718space and time with K<sub>m</sub> = <b>km_constant</b>
7719and K<sub>h</sub> = K<sub>m</sub> / <a href="chapter_4.2.html#prandtl_number">prandtl_number</a>.
7720The prognostic equation for the subgrid-scale TKE is switched off.
7721Constant eddy diffusivities are only allowed with the Prandtl layer (<a href="#prandtl_layer">prandtl_layer</a>)
7722switched off.</p>
7723
7724
7725
7726
7727
7728
7729
7730
7731
7732
7733      </td>
7734
7735
7736
7737
7738
7739
7740
7741
7742
7743
7744    </tr>
7745
7746
7747
7748
7749
7750
7751
7752
7753
7754
7755    <tr>
7756
7757
7758
7759
7760
7761
7762
7763
7764
7765
7766      <td style="vertical-align: top;">
7767     
7768     
7769     
7770     
7771     
7772     
7773     
7774     
7775     
7776     
7777      <p><a name="km_damp_max"></a><b>km_damp_max</b></p>
7778
7779
7780
7781
7782
7783
7784
7785
7786
7787
7788      </td>
7789
7790
7791
7792
7793
7794
7795
7796
7797
7798
7799      <td style="vertical-align: top;">R</td>
7800
7801
7802
7803
7804
7805
7806
7807
7808
7809
7810      <td style="vertical-align: top;"><span style="font-style: italic;">0.5*(dx
7811or dy)</span></td>
7812
7813
7814
7815
7816
7817
7818
7819
7820
7821
7822      <td style="vertical-align: top;">Maximum
7823diffusivity used for filtering the velocity field in the vicinity of
7824the outflow (in m<sup>2</sup>/s).<br>
7825
7826
7827
7828
7829
7830
7831
7832
7833
7834
7835      <br>
7836
7837
7838
7839
7840
7841
7842
7843
7844
7845
7846When using non-cyclic lateral boundaries (see <a href="#bc_lr">bc_lr</a>
7847or <a href="#bc_ns">bc_ns</a>),
7848a smoothing has to be applied to the
7849velocity field in the vicinity of the outflow in order to suppress any
7850reflections of outgoing disturbances. Smoothing is done by increasing
7851the eddy diffusivity along the horizontal direction which is
7852perpendicular to the outflow boundary. Only velocity components
7853parallel to the outflow boundary are filtered (e.g. v and w, if the
7854outflow is along x). Damping is applied from the bottom to the top of
7855the domain.<br>
7856
7857
7858
7859
7860
7861
7862
7863
7864
7865
7866      <br>
7867
7868
7869
7870
7871
7872
7873
7874
7875
7876
7877The horizontal range of the smoothing is controlled by <a href="#outflow_damping_width">outflow_damping_width</a>
7878which defines the number of gridpoints (counted from the outflow
7879boundary) from where on the smoothing is applied. Starting from that
7880point, the eddy diffusivity is linearly increased (from zero to its
7881maximum value given by <span style="font-weight: bold;">km_damp_max</span>)
7882until half of the damping range width, from where it remains constant
7883up to the outflow boundary. If at a certain grid point the eddy
7884diffusivity calculated from the flow field is larger than as described
7885above, it is used instead.<br>
7886
7887
7888
7889
7890
7891
7892
7893
7894
7895
7896      <br>
7897
7898
7899
7900
7901
7902
7903
7904
7905
7906
7907The default value of <span style="font-weight: bold;">km_damp_max</span>
7908has been empirically proven to be sufficient.</td>
7909
7910
7911
7912
7913
7914
7915
7916
7917
7918
7919    </tr>
7920
7921
7922
7923
7924
7925
7926
7927
7928
7929
7930    <tr>
7931
7932
7933
7934
7935
7936
7937
7938
7939
7940
7941      <td style="vertical-align: top;">
7942     
7943     
7944     
7945     
7946     
7947     
7948     
7949     
7950     
7951     
7952      <p><a name="long_filter_factor"></a><b>long_filter_factor</b></p>
7953
7954
7955
7956
7957
7958
7959
7960
7961
7962
7963      </td>
7964
7965
7966
7967
7968
7969
7970
7971
7972
7973
7974      <td style="vertical-align: top;">R</td>
7975
7976
7977
7978
7979
7980
7981
7982
7983
7984
7985      <td style="vertical-align: top;"><i>0.0</i></td>
7986
7987
7988
7989
7990
7991
7992
7993
7994
7995
7996      <td style="vertical-align: top;">
7997     
7998     
7999     
8000     
8001     
8002     
8003     
8004     
8005     
8006     
8007      <p>Filter factor for the so-called Long-filter.<br>
8008
8009
8010
8011
8012
8013
8014
8015
8016
8017
8018      </p>
8019
8020
8021
8022
8023
8024
8025
8026
8027
8028
8029     
8030     
8031     
8032     
8033     
8034     
8035     
8036     
8037     
8038     
8039      <p><br>
8040
8041
8042
8043
8044
8045
8046
8047
8048
8049
8050This filter very efficiently
8051eliminates 2-delta-waves sometimes cauesed by the upstream-spline
8052scheme (see Mahrer and
8053Pielke, 1978: Mon. Wea. Rev., 106, 818-830). It works in all three
8054directions in space. A value of <b>long_filter_factor</b> = <i>0.01</i>
8055sufficiently removes the small-scale waves without affecting the
8056longer waves.<br>
8057
8058
8059
8060
8061
8062
8063
8064
8065
8066
8067      </p>
8068
8069
8070
8071
8072
8073
8074
8075
8076
8077
8078     
8079     
8080     
8081     
8082     
8083     
8084     
8085     
8086     
8087     
8088      <p>By default, the filter is switched off (= <i>0.0</i>).
8089It is exclusively applied to the tendencies calculated by the
8090upstream-spline scheme (see <a href="#momentum_advec">momentum_advec</a>
8091and <a href="#scalar_advec">scalar_advec</a>),
8092not to the prognostic variables themselves. At the bottom and top
8093boundary of the model domain the filter effect for vertical
80942-delta-waves is reduced. There, the amplitude of these waves is only
8095reduced by approx. 50%, otherwise by nearly 100%.&nbsp; <br>
8096
8097
8098
8099
8100
8101
8102
8103
8104
8105
8106Filter factors with values &gt; <i>0.01</i> also reduce the amplitudes
8107of waves with wavelengths longer than 2-delta (see the paper by Mahrer
8108and
8109Pielke, quoted above). </p>
8110
8111
8112
8113
8114
8115
8116
8117
8118
8119
8120      </td>
8121
8122
8123
8124
8125
8126
8127
8128
8129
8130
8131    </tr>
8132
8133
8134
8135
8136
8137
8138
8139
8140
8141
8142    <tr>
8143      <td style="vertical-align: top;"><a name="mixing_length_1d"></a><span style="font-weight: bold;">mixing_length_1d</span><br>
8144      </td>
8145      <td style="vertical-align: top;">C*20<br>
8146      </td>
8147      <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
8148      <span style="font-style: italic;">model'</span><br>
8149      </td>
8150      <td style="vertical-align: top;">Mixing length used in the 1d-model.<br>
8151      <br>
8152By default the mixing length is calculated as in the 3d-model (i.e. it depends on the grid spacing).<br>
8153      <br>
8154By setting <span style="font-weight: bold;">mixing_length_1d</span> = <span style="font-style: italic;">'blackadar'</span>,
8155the so-called Blackadar mixing length is used (l = kappa * z / ( 1 +
8156kappa * z / lambda ) with the limiting value lambda = 2.7E-4 * u_g / f).<br>
8157      </td>
8158    </tr>
8159    <tr>
8160      <td style="vertical-align: top;">
8161      <p><a name="moisture"></a><b>moisture</b></p>
8162      </td>
8163      <td style="vertical-align: top;">L</td>
8164      <td style="vertical-align: top;"><i>.F.</i></td>
8165      <td style="vertical-align: top;">
8166      <p>Parameter to switch on the prognostic equation for specific
8167humidity q.<br>
8168
8169
8170
8171
8172
8173
8174
8175
8176
8177
8178      </p>
8179
8180
8181
8182
8183
8184
8185
8186
8187
8188
8189
8190     
8191     
8192     
8193     
8194     
8195     
8196     
8197     
8198     
8199     
8200     
8201      <p>The initial vertical profile of q can be set via parameters <a href="chapter_4.1.html#q_surface">q_surface</a>, <a href="chapter_4.1.html#q_vertical_gradient">q_vertical_gradient</a>
8202and <a href="chapter_4.1.html#q_vertical_gradient_level">q_vertical_gradient_level</a>.&nbsp;
8203Boundary conditions can be set via <a href="chapter_4.1.html#q_surface_initial_change">q_surface_initial_change</a>
8204and <a href="chapter_4.1.html#surface_waterflux">surface_waterflux</a>.<br>
8205
8206
8207
8208
8209
8210
8211
8212
8213
8214
8215      </p>
8216
8217
8218
8219
8220
8221
8222
8223
8224
8225
8226
8227If the condensation scheme is switched on (<a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
8228= .TRUE.), q becomes the total liquid water content (sum of specific
8229humidity and liquid water content).</td>
8230    </tr>
8231<tr>
8232
8233
8234
8235
8236
8237
8238
8239
8240
8241
8242      <td style="vertical-align: top;">
8243     
8244     
8245     
8246     
8247     
8248     
8249     
8250     
8251     
8252     
8253      <p><a name="momentum_advec"></a><b>momentum_advec</b></p>
8254
8255
8256
8257
8258
8259
8260
8261
8262
8263
8264      </td>
8265
8266
8267
8268
8269
8270
8271
8272
8273
8274
8275      <td style="vertical-align: top;">C * 10</td>
8276
8277
8278
8279
8280
8281
8282
8283
8284
8285
8286      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
8287
8288
8289
8290
8291
8292
8293
8294
8295
8296
8297      <td style="vertical-align: top;">
8298     
8299     
8300     
8301     
8302     
8303     
8304     
8305     
8306     
8307     
8308      <p>Advection scheme to be used for the momentum equations.<br>
8309
8310
8311
8312
8313
8314
8315
8316
8317
8318
8319      <br>
8320
8321
8322
8323
8324
8325
8326
8327
8328
8329
8330The user can choose between the following schemes:<br>
8331
8332
8333
8334
8335
8336
8337
8338
8339
8340
8341&nbsp;<br>
8342
8343
8344
8345
8346
8347
8348
8349
8350
8351
8352      <br>
8353
8354
8355
8356
8357
8358
8359
8360
8361
8362
8363      <span style="font-style: italic;">'pw-scheme'</span><br>
8364
8365
8366
8367
8368
8369
8370
8371
8372
8373
8374      </p>
8375
8376
8377
8378
8379
8380
8381
8382
8383
8384
8385     
8386     
8387     
8388     
8389     
8390     
8391     
8392     
8393     
8394     
8395      <div style="margin-left: 40px;">The scheme of Piascek and
8396Williams (1970, J. Comp. Phys., 6,
8397392-405) with central differences in the form C3 is used.<br>
8398
8399
8400
8401
8402
8403
8404
8405
8406
8407
8408If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
8409= <span style="font-style: italic;">'leapfrog+euler'</span> the
8410advection scheme is - for the Euler-timestep - automatically switched
8411to an upstream-scheme.<br>
8412
8413
8414
8415
8416
8417
8418
8419
8420
8421
8422      </div>
8423
8424
8425
8426
8427
8428
8429
8430
8431
8432
8433     
8434     
8435     
8436     
8437     
8438     
8439     
8440     
8441     
8442     
8443      <p> </p>
8444
8445
8446
8447
8448
8449
8450
8451
8452
8453
8454     
8455     
8456     
8457     
8458     
8459     
8460     
8461     
8462     
8463     
8464      <p><span style="font-style: italic;">'ups-scheme'</span><br>
8465
8466
8467
8468
8469
8470
8471
8472
8473
8474
8475      </p>
8476
8477
8478
8479
8480
8481
8482
8483
8484
8485
8486     
8487     
8488     
8489     
8490     
8491     
8492     
8493     
8494     
8495     
8496      <div style="margin-left: 40px;">The upstream-spline scheme is
8497used
8498(see Mahrer and Pielke,
84991978: Mon. Wea. Rev., 106, 818-830). In opposite to the
8500Piascek-Williams scheme, this is characterized by much better numerical
8501features (less numerical diffusion, better preservation of flow
8502structures, e.g. vortices), but computationally it is much more
8503expensive. In
8504addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
8505= <span style="font-style: italic;">'</span><i>euler'</i>), i.e. the
8506timestep accuracy is only of first order.
8507For this reason the advection of scalar variables (see <a href="#scalar_advec">scalar_advec</a>)
8508should then also be carried out with the upstream-spline scheme,
8509because otherwise the scalar variables would
8510be subject to large numerical diffusion due to the upstream
8511scheme.&nbsp; </div>
8512
8513
8514
8515
8516
8517
8518
8519
8520
8521
8522     
8523     
8524     
8525     
8526     
8527     
8528     
8529     
8530     
8531     
8532      <p style="margin-left: 40px;">Since the cubic splines used tend
8533to overshoot under
8534certain circumstances, this effect must be adjusted by suitable
8535filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
8536      <a href="#long_filter_factor">long_filter_factor</a>, <a href="#ups_limit_pt">ups_limit_pt</a>, <a href="#ups_limit_u">ups_limit_u</a>,
8537      <a href="#ups_limit_v">ups_limit_v</a>, <a href="#ups_limit_w">ups_limit_w</a>).
8538This is always neccessary for runs with stable stratification,
8539even if this stratification appears only in parts of the model domain.<br>
8540
8541
8542
8543
8544
8545
8546
8547
8548
8549
8550      </p>
8551
8552
8553
8554
8555
8556
8557
8558
8559
8560
8561     
8562     
8563     
8564     
8565     
8566     
8567     
8568     
8569     
8570     
8571      <div style="margin-left: 40px;">With stable stratification the
8572upstream-spline scheme also
8573produces gravity waves with large amplitude, which must be
8574suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
8575
8576
8577
8578
8579
8580
8581
8582
8583
8584
8585      <br>
8586
8587
8588
8589
8590
8591
8592
8593
8594
8595
8596      <span style="font-weight: bold;">Important: </span>The&nbsp;
8597upstream-spline scheme is not implemented for humidity and passive
8598scalars (see <a href="#moisture">moisture</a>
8599and <a href="#passive_scalar">passive_scalar</a>)
8600and requires the use of a 2d-domain-decomposition. The last conditions
8601severely restricts code optimization on several machines leading to
8602very long execution times! The scheme is also not allowed for
8603non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
8604and <a href="#bc_ns">bc_ns</a>).</div>
8605
8606
8607
8608
8609
8610
8611
8612
8613
8614
8615      </td>
8616
8617
8618
8619
8620
8621
8622
8623
8624
8625
8626    </tr>
8627
8628
8629
8630
8631
8632
8633
8634
8635
8636
8637   
8638
8639
8640
8641
8642
8643
8644
8645
8646
8647
8648    <tr>
8649      <td style="vertical-align: top;"><a name="netcdf_precision"></a><span style="font-weight: bold;">netcdf_precision</span><br>
8650      </td>
8651      <td style="vertical-align: top;">C*20<br>
8652(10)<br>
8653      </td>
8654      <td style="vertical-align: top;"><span style="font-style: italic;">single preci-</span><br style="font-style: italic;">
8655      <span style="font-style: italic;">sion for all</span><br style="font-style: italic;">
8656      <span style="font-style: italic;">output quan-</span><br style="font-style: italic;">
8657      <span style="font-style: italic;">tities</span><br>
8658      </td>
8659      <td style="vertical-align: top;">Defines the accuracy of the NetCDF output.<br>
8660      <br>
8661By default, all NetCDF output data (see <a href="chapter_4.2.html#data_output_format">data_output_format</a>) have single precision&nbsp; (4 byte) accuracy. Double precision (8 byte) can be choosen alternatively.<br>
8662Accuracy for the different output data (cross sections, 3d-volume data, spectra, etc.) can be set independently.<br>
8663      <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL4'</span> (single precision) or <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL8'</span> (double precision) are the two principally allowed values for <span style="font-weight: bold;">netcdf_precision</span>, where the string <span style="font-style: italic;">'&lt;out&gt;' </span>can be chosen out of the following list:<br>
8664      <br>
8665      <table style="text-align: left; width: 284px; height: 234px;" border="1" cellpadding="2" cellspacing="2">
8666        <tbody>
8667          <tr>
8668            <td style="vertical-align: top;"><span style="font-style: italic;">'xy'</span><br>
8669            </td>
8670            <td style="vertical-align: top;">horizontal cross section<br>
8671            </td>
8672          </tr>
8673          <tr>
8674            <td style="vertical-align: top;"><span style="font-style: italic;">'xz'</span><br>
8675            </td>
8676            <td style="vertical-align: top;">vertical (xz) cross section<br>
8677            </td>
8678          </tr>
8679          <tr>
8680            <td style="vertical-align: top;"><span style="font-style: italic;">'yz'</span><br>
8681            </td>
8682            <td style="vertical-align: top;">vertical (yz) cross section<br>
8683            </td>
8684          </tr>
8685          <tr>
8686            <td style="vertical-align: top;"><span style="font-style: italic;">'2d'</span><br>
8687            </td>
8688            <td style="vertical-align: top;">all cross sections<br>
8689            </td>
8690          </tr>
8691          <tr>
8692            <td style="vertical-align: top;"><span style="font-style: italic;">'3d'</span><br>
8693            </td>
8694            <td style="vertical-align: top;">volume data<br>
8695            </td>
8696          </tr>
8697          <tr>
8698            <td style="vertical-align: top;"><span style="font-style: italic;">'pr'</span><br>
8699            </td>
8700            <td style="vertical-align: top;">vertical profiles<br>
8701            </td>
8702          </tr>
8703          <tr>
8704            <td style="vertical-align: top;"><span style="font-style: italic;">'ts'</span><br>
8705            </td>
8706            <td style="vertical-align: top;">time series, particle time series<br>
8707            </td>
8708          </tr>
8709          <tr>
8710            <td style="vertical-align: top;"><span style="font-style: italic;">'sp'</span><br>
8711            </td>
8712            <td style="vertical-align: top;">spectra<br>
8713            </td>
8714          </tr>
8715          <tr>
8716            <td style="vertical-align: top;"><span style="font-style: italic;">'prt'</span><br>
8717            </td>
8718            <td style="vertical-align: top;">particles<br>
8719            </td>
8720          </tr>
8721          <tr>
8722            <td style="vertical-align: top;"><span style="font-style: italic;">'all'</span><br>
8723            </td>
8724            <td style="vertical-align: top;">all output quantities<br>
8725            </td>
8726          </tr>
8727        </tbody>
8728      </table>
8729      <br>
8730      <span style="font-weight: bold;">Example:</span><br>
8731If all cross section data and the particle data shall be output in
8732double precision and all other quantities in single precision, then <span style="font-weight: bold;">netcdf_precision</span> = <span style="font-style: italic;">'2d_NF90_REAL8'</span>, <span style="font-style: italic;">'prt_NF90_REAL8'</span> has to be assigned.<br>
8733      </td>
8734    </tr>
8735<tr>
8736
8737
8738
8739
8740
8741
8742
8743
8744
8745
8746      <td style="vertical-align: top;">
8747     
8748     
8749     
8750     
8751     
8752     
8753     
8754     
8755     
8756     
8757      <p><a name="npex"></a><b>npex</b></p>
8758
8759
8760
8761
8762
8763
8764
8765
8766
8767
8768      </td>
8769
8770
8771
8772
8773
8774
8775
8776
8777
8778
8779      <td style="vertical-align: top;">I</td>
8780
8781
8782
8783
8784
8785
8786
8787
8788
8789
8790      <td style="vertical-align: top;"><br>
8791
8792
8793
8794
8795
8796
8797
8798
8799
8800
8801      </td>
8802
8803
8804
8805
8806
8807
8808
8809
8810
8811
8812      <td style="vertical-align: top;">
8813     
8814     
8815     
8816     
8817     
8818     
8819     
8820     
8821     
8822     
8823      <p>Number of processors along x-direction of the virtual
8824processor
8825net.&nbsp; </p>
8826
8827
8828
8829
8830
8831
8832
8833
8834
8835
8836     
8837     
8838     
8839     
8840     
8841     
8842     
8843     
8844     
8845     
8846      <p>For parallel runs, the total number of processors to be used
8847is given by
8848the <span style="font-weight: bold;">mrun</span> option <a href="http://www.muk.uni-hannover.de/software/mrun_beschreibung.html#Opt-X">-X</a>.
8849By default, depending on the type of the parallel computer, PALM
8850generates a 1d processor
8851net (domain decomposition along x, <span style="font-weight: bold;">npey</span>
8852= <span style="font-style: italic;">1</span>) or a 2d-net (this is
8853favored on machines with fast communication network). In case of a
88542d-net, it is tried to make it more or less square-shaped. If, for
8855example, 16 processors are assigned (-X 16), a 4 * 4 processor net is
8856generated (<span style="font-weight: bold;">npex</span> = <span style="font-style: italic;">4</span>, <span style="font-weight: bold;">npey</span>
8857= <span style="font-style: italic;">4</span>).
8858This choice is optimal for square total domains (<a href="#nx">nx</a>
8859= <a href="#ny">ny</a>),
8860since then the number of ghost points at the lateral boundarys of
8861the subdomains is minimal. If <span style="font-weight: bold;">nx</span>
8862nd <span style="font-weight: bold;">ny</span> differ extremely, the
8863processor net should be manually adjusted using adequate values for <span style="font-weight: bold;">npex</span> and <span style="font-weight: bold;">npey</span>.&nbsp; </p>
8864
8865
8866
8867
8868
8869
8870
8871
8872
8873
8874     
8875     
8876     
8877     
8878     
8879     
8880     
8881     
8882     
8883     
8884      <p><b>Important:</b> The value of <span style="font-weight: bold;">npex</span> * <span style="font-weight: bold;">npey</span> must exactly correspond to the
8885value assigned by the <span style="font-weight: bold;">mrun</span>-option
8886      <tt>-X</tt>.
8887Otherwise the model run will abort with a corresponding error
8888message.&nbsp; <br>
8889
8890
8891
8892
8893
8894
8895
8896
8897
8898
8899Additionally, the specification of <span style="font-weight: bold;">npex</span>
8900and <span style="font-weight: bold;">npey</span> may of course
8901override the default setting for the domain decomposition (1d or 2d)
8902which may have a significant (negative) effect on the code performance.
8903      </p>
8904
8905
8906
8907
8908
8909
8910
8911
8912
8913
8914      </td>
8915
8916
8917
8918
8919
8920
8921
8922
8923
8924
8925    </tr>
8926
8927
8928
8929
8930
8931
8932
8933
8934
8935
8936    <tr>
8937
8938
8939
8940
8941
8942
8943
8944
8945
8946
8947      <td style="vertical-align: top;">
8948     
8949     
8950     
8951     
8952     
8953     
8954     
8955     
8956     
8957     
8958      <p><a name="npey"></a><b>npey</b></p>
8959
8960
8961
8962
8963
8964
8965
8966
8967
8968
8969      </td>
8970
8971
8972
8973
8974
8975
8976
8977
8978
8979
8980      <td style="vertical-align: top;">I</td>
8981
8982
8983
8984
8985
8986
8987
8988
8989
8990
8991      <td style="vertical-align: top;"><br>
8992
8993
8994
8995
8996
8997
8998
8999
9000
9001
9002      </td>
9003
9004
9005
9006
9007
9008
9009
9010
9011
9012
9013      <td style="vertical-align: top;">
9014     
9015     
9016     
9017     
9018     
9019     
9020     
9021     
9022     
9023     
9024      <p>Number of processors along y-direction of the virtual
9025processor
9026net.&nbsp; </p>
9027
9028
9029
9030
9031
9032
9033
9034
9035
9036
9037     
9038     
9039     
9040     
9041     
9042     
9043     
9044     
9045     
9046     
9047      <p>For further information see <a href="#npex">npex</a>.</p>
9048
9049
9050
9051
9052
9053
9054
9055
9056
9057
9058      </td>
9059
9060
9061
9062
9063
9064
9065
9066
9067
9068
9069    </tr>
9070
9071
9072
9073
9074
9075
9076
9077
9078
9079
9080    <tr>
9081
9082
9083
9084
9085
9086
9087
9088
9089
9090
9091      <td style="vertical-align: top;">
9092     
9093     
9094     
9095     
9096     
9097     
9098     
9099     
9100     
9101     
9102      <p><a name="nsor_ini"></a><b>nsor_ini</b></p>
9103
9104
9105
9106
9107
9108
9109
9110
9111
9112
9113      </td>
9114
9115
9116
9117
9118
9119
9120
9121
9122
9123
9124      <td style="vertical-align: top;">I</td>
9125
9126
9127
9128
9129
9130
9131
9132
9133
9134
9135      <td style="vertical-align: top;"><i>100</i></td>
9136
9137
9138
9139
9140
9141
9142
9143
9144
9145
9146      <td style="vertical-align: top;">
9147     
9148     
9149     
9150     
9151     
9152     
9153     
9154     
9155     
9156     
9157      <p>Initial number of iterations with the SOR algorithm.&nbsp; </p>
9158
9159
9160
9161
9162
9163
9164
9165
9166
9167
9168     
9169     
9170     
9171     
9172     
9173     
9174     
9175     
9176     
9177     
9178      <p>This parameter is only effective if the SOR algorithm was
9179selected as the pressure solver scheme (<a href="chapter_4.2.html#psolver">psolver</a>
9180= <span style="font-style: italic;">'sor'</span>) and specifies the
9181number of initial iterations of the SOR
9182scheme (at t = 0). The number of subsequent iterations at the following
9183timesteps is determined
9184with the parameter <a href="#nsor">nsor</a>.
9185Usually <b>nsor</b> &lt; <b>nsor_ini</b>, since in each case
9186subsequent calls to <a href="chapter_4.2.html#psolver">psolver</a>
9187use the solution of the previous call as initial value. Suitable
9188test runs should determine whether sufficient convergence of the
9189solution is obtained with the default value and if necessary the value
9190of <b>nsor_ini</b> should be changed.</p>
9191
9192
9193
9194
9195
9196
9197
9198
9199
9200
9201      </td>
9202
9203
9204
9205
9206
9207
9208
9209
9210
9211
9212    </tr>
9213
9214
9215
9216
9217
9218
9219
9220
9221
9222
9223    <tr>
9224
9225
9226
9227
9228
9229
9230
9231
9232
9233
9234      <td style="vertical-align: top;">
9235     
9236     
9237     
9238     
9239     
9240     
9241     
9242     
9243     
9244     
9245      <p><a name="nx"></a><b>nx</b></p>
9246
9247
9248
9249
9250
9251
9252
9253
9254
9255
9256      </td>
9257
9258
9259
9260
9261
9262
9263
9264
9265
9266
9267      <td style="vertical-align: top;">I</td>
9268
9269
9270
9271
9272
9273
9274
9275
9276
9277
9278      <td style="vertical-align: top;"><br>
9279
9280
9281
9282
9283
9284
9285
9286
9287
9288
9289      </td>
9290
9291
9292
9293
9294
9295
9296
9297
9298
9299
9300      <td style="vertical-align: top;">
9301     
9302     
9303     
9304     
9305     
9306     
9307     
9308     
9309     
9310     
9311      <p>Number of grid points in x-direction.&nbsp; </p>
9312
9313
9314
9315
9316
9317
9318
9319
9320
9321
9322     
9323     
9324     
9325     
9326     
9327     
9328     
9329     
9330     
9331     
9332      <p>A value for this parameter must be assigned. Since the lower
9333array bound in PALM
9334starts with i = 0, the actual number of grid points is equal to <b>nx+1</b>.
9335In case of cyclic boundary conditions along x, the domain size is (<b>nx+1</b>)*
9336      <a href="#dx">dx</a>.</p>
9337
9338
9339
9340
9341
9342
9343
9344
9345
9346
9347     
9348     
9349     
9350     
9351     
9352     
9353     
9354     
9355     
9356     
9357      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
9358= <span style="font-style: italic;">'strict'</span>, <b>nx+1</b> must
9359be an integral multiple
9360of the processor numbers (see <a href="#npex">npex</a>
9361and <a href="#npey">npey</a>)
9362along x- as well as along y-direction (due to data
9363transposition restrictions).</p>
9364
9365
9366
9367
9368
9369
9370
9371
9372
9373
9374      </td>
9375
9376
9377
9378
9379
9380
9381
9382
9383
9384
9385    </tr>
9386
9387
9388
9389
9390
9391
9392
9393
9394
9395
9396    <tr>
9397
9398
9399
9400
9401
9402
9403
9404
9405
9406
9407      <td style="vertical-align: top;">
9408     
9409     
9410     
9411     
9412     
9413     
9414     
9415     
9416     
9417     
9418      <p><a name="ny"></a><b>ny</b></p>
9419
9420
9421
9422
9423
9424
9425
9426
9427
9428
9429      </td>
9430
9431
9432
9433
9434
9435
9436
9437
9438
9439
9440      <td style="vertical-align: top;">I</td>
9441
9442
9443
9444
9445
9446
9447
9448
9449
9450
9451      <td style="vertical-align: top;"><br>
9452
9453
9454
9455
9456
9457
9458
9459
9460
9461
9462      </td>
9463
9464
9465
9466
9467
9468
9469
9470
9471
9472
9473      <td style="vertical-align: top;">
9474     
9475     
9476     
9477     
9478     
9479     
9480     
9481     
9482     
9483     
9484      <p>Number of grid points in y-direction.&nbsp; </p>
9485
9486
9487
9488
9489
9490
9491
9492
9493
9494
9495     
9496     
9497     
9498     
9499     
9500     
9501     
9502     
9503     
9504     
9505      <p>A value for this parameter must be assigned. Since the lower
9506array bound in PALM starts with i = 0, the actual number of grid points
9507is equal to <b>ny+1</b>. In case of cyclic boundary conditions along
9508y, the domain size is (<b>ny+1</b>) * <a href="#dy">dy</a>.</p>
9509
9510
9511
9512
9513
9514
9515
9516
9517
9518
9519     
9520     
9521     
9522     
9523     
9524     
9525     
9526     
9527     
9528     
9529      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
9530= <span style="font-style: italic;">'strict'</span>, <b>ny+1</b> must
9531be an integral multiple
9532of the processor numbers (see <a href="#npex">npex</a>
9533and <a href="#npey">npey</a>)&nbsp;
9534along y- as well as along x-direction (due to data
9535transposition restrictions).</p>
9536
9537
9538
9539
9540
9541
9542
9543
9544
9545
9546      </td>
9547
9548
9549
9550
9551
9552
9553
9554
9555
9556
9557    </tr>
9558
9559
9560
9561
9562
9563
9564
9565
9566
9567
9568    <tr>
9569
9570
9571
9572
9573
9574
9575
9576
9577
9578
9579      <td style="vertical-align: top;">
9580     
9581     
9582     
9583     
9584     
9585     
9586     
9587     
9588     
9589     
9590      <p><a name="nz"></a><b>nz</b></p>
9591
9592
9593
9594
9595
9596
9597
9598
9599
9600
9601      </td>
9602
9603
9604
9605
9606
9607
9608
9609
9610
9611
9612      <td style="vertical-align: top;">I</td>
9613
9614
9615
9616
9617
9618
9619
9620
9621
9622
9623      <td style="vertical-align: top;"><br>
9624
9625
9626
9627
9628
9629
9630
9631
9632
9633
9634      </td>
9635
9636
9637
9638
9639
9640
9641
9642
9643
9644
9645      <td style="vertical-align: top;">
9646     
9647     
9648     
9649     
9650     
9651     
9652     
9653     
9654     
9655     
9656      <p>Number of grid points in z-direction.&nbsp; </p>
9657
9658
9659
9660
9661
9662
9663
9664
9665
9666
9667     
9668     
9669     
9670     
9671     
9672     
9673     
9674     
9675     
9676     
9677      <p>A value for this parameter must be assigned. Since the lower
9678array bound in PALM
9679starts with k = 0 and since one additional grid point is added at the
9680top boundary (k = <b>nz+1</b>), the actual number of grid points is <b>nz+2</b>.
9681However, the prognostic equations are only solved up to <b>nz</b> (u,
9682v)
9683or up to <b>nz-1</b> (w, scalar quantities). The top boundary for u
9684and v is at k = <b>nz+1</b> (u, v) while at k = <b>nz</b> for all
9685other quantities.&nbsp; </p>
9686
9687
9688
9689
9690
9691
9692
9693
9694
9695
9696     
9697     
9698     
9699     
9700     
9701     
9702     
9703     
9704     
9705     
9706      <p>For parallel runs,&nbsp; in case of <a href="#grid_matching">grid_matching</a>
9707= <span style="font-style: italic;">'strict'</span>, <b>nz</b> must
9708be an integral multiple of
9709the number of processors in x-direction (due to data transposition
9710restrictions).</p>
9711
9712
9713
9714
9715
9716
9717
9718
9719
9720
9721      </td>
9722
9723
9724
9725
9726
9727
9728
9729
9730
9731
9732    </tr>
9733
9734
9735
9736
9737
9738
9739
9740
9741
9742
9743    <tr>
9744
9745
9746
9747
9748
9749
9750
9751
9752
9753
9754      <td style="vertical-align: top;">
9755     
9756     
9757     
9758     
9759     
9760     
9761     
9762     
9763     
9764     
9765      <p><a name="omega"></a><b>omega</b></p>
9766
9767
9768
9769
9770
9771
9772
9773
9774
9775
9776      </td>
9777
9778
9779
9780
9781
9782
9783
9784
9785
9786
9787      <td style="vertical-align: top;">R</td>
9788
9789
9790
9791
9792
9793
9794
9795
9796
9797
9798      <td style="vertical-align: top;"><i>7.29212E-5</i></td>
9799
9800
9801
9802
9803
9804
9805
9806
9807
9808
9809      <td style="vertical-align: top;">
9810     
9811     
9812     
9813     
9814     
9815     
9816     
9817     
9818     
9819     
9820      <p>Angular velocity of the rotating system (in rad s<sup>-1</sup>).&nbsp;
9821      </p>
9822
9823
9824
9825
9826
9827
9828
9829
9830
9831
9832     
9833     
9834     
9835     
9836     
9837     
9838     
9839     
9840     
9841     
9842      <p>The angular velocity of the earth is set by default. The
9843values
9844of the Coriolis parameters are calculated as:&nbsp; </p>
9845
9846
9847
9848
9849
9850
9851
9852
9853
9854
9855     
9856     
9857     
9858     
9859     
9860     
9861     
9862     
9863     
9864     
9865      <ul>
9866
9867
9868
9869
9870
9871
9872
9873
9874
9875
9876       
9877       
9878       
9879       
9880       
9881       
9882       
9883       
9884       
9885       
9886        <p>f = 2.0 * <b>omega</b> * sin(<a href="#phi">phi</a>)&nbsp; <br>
9887
9888
9889
9890
9891
9892
9893
9894
9895
9896
9897f* = 2.0 * <b>omega</b> * cos(<a href="#phi">phi</a>)</p>
9898
9899
9900
9901
9902
9903
9904
9905
9906
9907
9908     
9909     
9910     
9911     
9912     
9913     
9914     
9915     
9916     
9917     
9918      </ul>
9919
9920
9921
9922
9923
9924
9925
9926
9927
9928
9929      </td>
9930
9931
9932
9933
9934
9935
9936
9937
9938
9939
9940    </tr>
9941
9942
9943
9944
9945
9946
9947
9948
9949
9950
9951    <tr>
9952      <td style="vertical-align: top;">
9953      <p><a name="outflow_damping_width"></a><b>outflow_damping_width</b></p>
9954      </td>
9955      <td style="vertical-align: top;">I</td>
9956      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(20,
9957nx/2</span> or <span style="font-style: italic;">ny/2)</span></td>
9958      <td style="vertical-align: top;">Width of
9959the damping range in the vicinity of the outflow (gridpoints).<br>
9960
9961
9962
9963
9964
9965
9966
9967
9968
9969
9970
9971      <br>
9972
9973
9974
9975
9976
9977
9978
9979
9980
9981
9982
9983When using non-cyclic lateral boundaries (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
9984or <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
9985a smoothing has to be applied to the
9986velocity field in the vicinity of the outflow in order to suppress any
9987reflections of outgoing disturbances. This parameter controlls the
9988horizontal range to which the smoothing is applied. The range is given
9989in gridpoints counted from the respective outflow boundary. For further
9990details about the smoothing see parameter <a href="chapter_4.1.html#km_damp_max">km_damp_max</a>,
9991which defines the magnitude of the damping.</td>
9992    </tr>
9993<tr>
9994
9995
9996
9997
9998
9999
10000
10001
10002
10003
10004      <td style="vertical-align: top;">
10005     
10006     
10007     
10008     
10009     
10010     
10011     
10012     
10013     
10014     
10015      <p><a name="overshoot_limit_e"></a><b>overshoot_limit_e</b></p>
10016
10017
10018
10019
10020
10021
10022
10023
10024
10025
10026      </td>
10027
10028
10029
10030
10031
10032
10033
10034
10035
10036
10037      <td style="vertical-align: top;">R</td>
10038
10039
10040
10041
10042
10043
10044
10045
10046
10047
10048      <td style="vertical-align: top;"><i>0.0</i></td>
10049
10050
10051
10052
10053
10054
10055
10056
10057
10058
10059      <td style="vertical-align: top;">
10060     
10061     
10062     
10063     
10064     
10065     
10066     
10067     
10068     
10069     
10070      <p>Allowed limit for the overshooting of subgrid-scale TKE in
10071case that the upstream-spline scheme is switched on (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
10072      </p>
10073
10074
10075
10076
10077
10078
10079
10080
10081
10082
10083     
10084     
10085     
10086     
10087     
10088     
10089     
10090     
10091     
10092     
10093      <p>By deafult, if cut-off of overshoots is switched on for the
10094upstream-spline scheme (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>),
10095no overshoots are permitted at all. If <b>overshoot_limit_e</b>
10096is given a non-zero value, overshoots with the respective
10097amplitude (both upward and downward) are allowed.&nbsp; </p>
10098
10099
10100
10101
10102
10103
10104
10105
10106
10107
10108     
10109     
10110     
10111     
10112     
10113     
10114     
10115     
10116     
10117     
10118      <p>Only positive values are allowed for <b>overshoot_limit_e</b>.</p>
10119
10120
10121
10122
10123
10124
10125
10126
10127
10128
10129      </td>
10130
10131
10132
10133
10134
10135
10136
10137
10138
10139
10140    </tr>
10141
10142
10143
10144
10145
10146
10147
10148
10149
10150
10151   
10152
10153
10154
10155
10156
10157
10158
10159
10160
10161
10162    <tr>
10163
10164
10165
10166
10167
10168
10169
10170
10171
10172
10173      <td style="vertical-align: top;">
10174     
10175     
10176     
10177     
10178     
10179     
10180     
10181     
10182     
10183     
10184      <p><a name="overshoot_limit_pt"></a><b>overshoot_limit_pt</b></p>
10185
10186
10187
10188
10189
10190
10191
10192
10193
10194
10195      </td>
10196
10197
10198
10199
10200
10201
10202
10203
10204
10205
10206      <td style="vertical-align: top;">R</td>
10207
10208
10209
10210
10211
10212
10213
10214
10215
10216
10217      <td style="vertical-align: top;"><i>0.0</i></td>
10218
10219
10220
10221
10222
10223
10224
10225
10226
10227
10228      <td style="vertical-align: top;">
10229     
10230     
10231     
10232     
10233     
10234     
10235     
10236     
10237     
10238     
10239      <p>Allowed limit for the overshooting of potential temperature in
10240case that the upstream-spline scheme is switched on (in K).&nbsp; </p>
10241
10242
10243
10244
10245
10246
10247
10248
10249
10250
10251     
10252     
10253     
10254     
10255     
10256     
10257     
10258     
10259     
10260     
10261      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
10262      </p>
10263
10264
10265
10266
10267
10268
10269
10270
10271
10272
10273     
10274     
10275     
10276     
10277     
10278     
10279     
10280     
10281     
10282     
10283      <p>Only positive values are allowed for <b>overshoot_limit_pt</b>.</p>
10284
10285
10286
10287
10288
10289
10290
10291
10292
10293
10294      </td>
10295
10296
10297
10298
10299
10300
10301
10302
10303
10304
10305    </tr>
10306
10307
10308
10309
10310
10311
10312
10313
10314
10315
10316    <tr>
10317
10318
10319
10320
10321
10322
10323
10324
10325
10326
10327      <td style="vertical-align: top;">
10328     
10329     
10330     
10331     
10332     
10333     
10334     
10335     
10336     
10337     
10338      <p><a name="overshoot_limit_u"></a><b>overshoot_limit_u</b></p>
10339
10340
10341
10342
10343
10344
10345
10346
10347
10348
10349      </td>
10350
10351
10352
10353
10354
10355
10356
10357
10358
10359
10360      <td style="vertical-align: top;">R</td>
10361
10362
10363
10364
10365
10366
10367
10368
10369
10370
10371      <td style="vertical-align: top;"><i>0.0</i></td>
10372
10373
10374
10375
10376
10377
10378
10379
10380
10381
10382      <td style="vertical-align: top;">Allowed limit for the
10383overshooting of
10384the u-component of velocity in case that the upstream-spline scheme is
10385switched on (in m/s).
10386     
10387     
10388     
10389     
10390     
10391     
10392     
10393     
10394     
10395     
10396      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
10397      </p>
10398
10399
10400
10401
10402
10403
10404
10405
10406
10407
10408     
10409     
10410     
10411     
10412     
10413     
10414     
10415     
10416     
10417     
10418      <p>Only positive values are allowed for <b>overshoot_limit_u</b>.</p>
10419
10420
10421
10422
10423
10424
10425
10426
10427
10428
10429      </td>
10430
10431
10432
10433
10434
10435
10436
10437
10438
10439
10440    </tr>
10441
10442
10443
10444
10445
10446
10447
10448
10449
10450
10451    <tr>
10452
10453
10454
10455
10456
10457
10458
10459
10460
10461
10462      <td style="vertical-align: top;">
10463     
10464     
10465     
10466     
10467     
10468     
10469     
10470     
10471     
10472     
10473      <p><a name="overshoot_limit_v"></a><b>overshoot_limit_v</b></p>
10474
10475
10476
10477
10478
10479
10480
10481
10482
10483
10484      </td>
10485
10486
10487
10488
10489
10490
10491
10492
10493
10494
10495      <td style="vertical-align: top;">R</td>
10496
10497
10498
10499
10500
10501
10502
10503
10504
10505
10506      <td style="vertical-align: top;"><i>0.0</i></td>
10507
10508
10509
10510
10511
10512
10513
10514
10515
10516
10517      <td style="vertical-align: top;">
10518     
10519     
10520     
10521     
10522     
10523     
10524     
10525     
10526     
10527     
10528      <p>Allowed limit for the overshooting of the v-component of
10529velocity in case that the upstream-spline scheme is switched on
10530(in m/s).&nbsp; </p>
10531
10532
10533
10534
10535
10536
10537
10538
10539
10540
10541     
10542     
10543     
10544     
10545     
10546     
10547     
10548     
10549     
10550     
10551      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
10552      </p>
10553
10554
10555
10556
10557
10558
10559
10560
10561
10562
10563     
10564     
10565     
10566     
10567     
10568     
10569     
10570     
10571     
10572     
10573      <p>Only positive values are allowed for <b>overshoot_limit_v</b>.</p>
10574
10575
10576
10577
10578
10579
10580
10581
10582
10583
10584      </td>
10585
10586
10587
10588
10589
10590
10591
10592
10593
10594
10595    </tr>
10596
10597
10598
10599
10600
10601
10602
10603
10604
10605
10606    <tr>
10607
10608
10609
10610
10611
10612
10613
10614
10615
10616
10617      <td style="vertical-align: top;">
10618     
10619     
10620     
10621     
10622     
10623     
10624     
10625     
10626     
10627     
10628      <p><a name="overshoot_limit_w"></a><b>overshoot_limit_w</b></p>
10629
10630
10631
10632
10633
10634
10635
10636
10637
10638
10639      </td>
10640
10641
10642
10643
10644
10645
10646
10647
10648
10649
10650      <td style="vertical-align: top;">R</td>
10651
10652
10653
10654
10655
10656
10657
10658
10659
10660
10661      <td style="vertical-align: top;"><i>0.0</i></td>
10662
10663
10664
10665
10666
10667
10668
10669
10670
10671
10672      <td style="vertical-align: top;">
10673     
10674     
10675     
10676     
10677     
10678     
10679     
10680     
10681     
10682     
10683      <p>Allowed limit for the overshooting of the w-component of
10684velocity in case that the upstream-spline scheme is switched on
10685(in m/s).&nbsp; </p>
10686
10687
10688
10689
10690
10691
10692
10693
10694
10695
10696     
10697     
10698     
10699     
10700     
10701     
10702     
10703     
10704     
10705     
10706      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
10707      </p>
10708
10709
10710
10711
10712
10713
10714
10715
10716
10717
10718     
10719     
10720     
10721     
10722     
10723     
10724     
10725     
10726     
10727     
10728      <p>Only positive values are permitted for <b>overshoot_limit_w</b>.</p>
10729
10730
10731
10732
10733
10734
10735
10736
10737
10738
10739      </td>
10740
10741
10742
10743
10744
10745
10746
10747
10748
10749
10750    </tr>
10751
10752
10753
10754
10755
10756
10757
10758
10759
10760
10761    <tr>
10762
10763
10764
10765
10766
10767
10768
10769
10770
10771
10772      <td style="vertical-align: top;">
10773     
10774     
10775     
10776     
10777     
10778     
10779     
10780     
10781     
10782     
10783      <p><a name="passive_scalar"></a><b>passive_scalar</b></p>
10784
10785
10786
10787
10788
10789
10790
10791
10792
10793
10794      </td>
10795
10796
10797
10798
10799
10800
10801
10802
10803
10804
10805      <td style="vertical-align: top;">L</td>
10806
10807
10808
10809
10810
10811
10812
10813
10814
10815
10816      <td style="vertical-align: top;"><i>.F.</i></td>
10817
10818
10819
10820
10821
10822
10823
10824
10825
10826
10827      <td style="vertical-align: top;">
10828     
10829     
10830     
10831     
10832     
10833     
10834     
10835     
10836     
10837     
10838      <p>Parameter to switch on the prognostic equation for a passive
10839scalar. <br>
10840
10841
10842
10843
10844
10845
10846
10847
10848
10849
10850      </p>
10851
10852
10853
10854
10855
10856
10857
10858
10859
10860
10861     
10862     
10863     
10864     
10865     
10866     
10867     
10868     
10869     
10870     
10871      <p>The initial vertical profile of s can be set via parameters <a href="#s_surface">s_surface</a>, <a href="#s_vertical_gradient">s_vertical_gradient</a>
10872and&nbsp; <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.
10873Boundary conditions can be set via <a href="#s_surface_initial_change">s_surface_initial_change</a>
10874and <a href="#surface_scalarflux">surface_scalarflux</a>.&nbsp; </p>
10875
10876
10877
10878
10879
10880
10881
10882
10883
10884
10885     
10886     
10887     
10888     
10889     
10890     
10891     
10892     
10893     
10894     
10895      <p><b>Note:</b> <br>
10896
10897
10898
10899
10900
10901
10902
10903
10904
10905
10906With <span style="font-weight: bold;">passive_scalar</span> switched
10907on, the simultaneous use of humidity (see <a href="#moisture">moisture</a>)
10908is impossible.</p>
10909
10910
10911
10912
10913
10914
10915
10916
10917
10918
10919      </td>
10920
10921
10922
10923
10924
10925
10926
10927
10928
10929
10930    </tr>
10931
10932
10933
10934
10935
10936
10937
10938
10939
10940
10941    <tr>
10942
10943
10944
10945
10946
10947
10948
10949
10950
10951
10952      <td style="vertical-align: top;">
10953     
10954     
10955     
10956     
10957     
10958     
10959     
10960     
10961     
10962     
10963      <p><a name="phi"></a><b>phi</b></p>
10964
10965
10966
10967
10968
10969
10970
10971
10972
10973
10974      </td>
10975
10976
10977
10978
10979
10980
10981
10982
10983
10984
10985      <td style="vertical-align: top;">R</td>
10986
10987
10988
10989
10990
10991
10992
10993
10994
10995
10996      <td style="vertical-align: top;"><i>55.0</i></td>
10997
10998
10999
11000
11001
11002
11003
11004
11005
11006
11007      <td style="vertical-align: top;">
11008     
11009     
11010     
11011     
11012     
11013     
11014     
11015     
11016     
11017     
11018      <p>Geographical latitude (in degrees).&nbsp; </p>
11019
11020
11021
11022
11023
11024
11025
11026
11027
11028
11029     
11030     
11031     
11032     
11033     
11034     
11035     
11036     
11037     
11038     
11039      <p>The value of this parameter determines the value of the
11040Coriolis parameters f and f*, provided that the angular velocity (see <a href="#omega">omega</a>)
11041is non-zero.</p>
11042
11043
11044
11045
11046
11047
11048
11049
11050
11051
11052      </td>
11053
11054
11055
11056
11057
11058
11059
11060
11061
11062
11063    </tr>
11064
11065
11066
11067
11068
11069
11070
11071
11072
11073
11074    <tr>
11075
11076
11077
11078
11079
11080
11081
11082
11083
11084
11085      <td style="vertical-align: top;">
11086     
11087     
11088     
11089     
11090     
11091     
11092     
11093     
11094     
11095     
11096      <p><a name="prandtl_layer"></a><b>prandtl_layer</b></p>
11097
11098
11099
11100
11101
11102
11103
11104
11105
11106
11107      </td>
11108
11109
11110
11111
11112
11113
11114
11115
11116
11117
11118      <td style="vertical-align: top;">L</td>
11119
11120
11121
11122
11123
11124
11125
11126
11127
11128
11129      <td style="vertical-align: top;"><i>.T.</i></td>
11130
11131
11132
11133
11134
11135
11136
11137
11138
11139
11140      <td style="vertical-align: top;">
11141     
11142     
11143     
11144     
11145     
11146     
11147     
11148     
11149     
11150     
11151      <p>Parameter to switch on a Prandtl layer.&nbsp; </p>
11152
11153
11154
11155
11156
11157
11158
11159
11160
11161
11162     
11163     
11164     
11165     
11166     
11167     
11168     
11169     
11170     
11171     
11172      <p>By default, a Prandtl layer is switched on at the bottom
11173boundary between z = 0 and z = 0.5 * <a href="#dz">dz</a>
11174(the first computational grid point above ground for u, v and the
11175scalar quantities).
11176In this case, at the bottom boundary, free-slip conditions for u and v
11177(see <a href="#bc_uv_b">bc_uv_b</a>)
11178are not allowed. Likewise, laminar
11179simulations with constant eddy diffusivities (<a href="#km_constant">km_constant</a>)
11180are forbidden.&nbsp; </p>
11181
11182
11183
11184
11185
11186
11187
11188
11189
11190
11191     
11192     
11193     
11194     
11195     
11196     
11197     
11198     
11199     
11200     
11201      <p>With Prandtl-layer switched off, the TKE boundary condition <a href="#bc_e_b">bc_e_b</a>
11202= '<i>(u*)**2+neumann'</i> must not be used and is automatically
11203changed to <i>'neumann'</i> if necessary.&nbsp; Also, the pressure
11204boundary condition <a href="#bc_p_b">bc_p_b</a>
11205= <i>'neumann+inhomo'</i>&nbsp; is not allowed. </p>
11206
11207
11208
11209
11210
11211
11212
11213
11214
11215
11216     
11217     
11218     
11219     
11220     
11221     
11222     
11223     
11224     
11225     
11226      <p>The roughness length is declared via the parameter <a href="#roughness_length">roughness_length</a>.</p>
11227
11228
11229
11230
11231
11232
11233
11234
11235
11236
11237      </td>
11238
11239
11240
11241
11242
11243
11244
11245
11246
11247
11248    </tr>
11249
11250
11251
11252
11253
11254
11255
11256
11257
11258
11259    <tr>
11260
11261
11262
11263
11264
11265
11266
11267
11268
11269
11270      <td style="vertical-align: top;">
11271     
11272     
11273     
11274     
11275     
11276     
11277     
11278     
11279     
11280     
11281      <p><a name="precipitation"></a><b>precipitation</b></p>
11282
11283
11284
11285
11286
11287
11288
11289
11290
11291
11292      </td>
11293
11294
11295
11296
11297
11298
11299
11300
11301
11302
11303      <td style="vertical-align: top;">L</td>
11304
11305
11306
11307
11308
11309
11310
11311
11312
11313
11314      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
11315
11316
11317
11318
11319
11320
11321
11322
11323
11324
11325      <td style="vertical-align: top;">
11326     
11327     
11328     
11329     
11330     
11331     
11332     
11333     
11334     
11335     
11336      <p>Parameter to switch on the precipitation scheme.<br>
11337
11338
11339
11340
11341
11342
11343
11344
11345
11346
11347      </p>
11348
11349
11350
11351
11352
11353
11354
11355
11356
11357
11358     
11359     
11360     
11361     
11362     
11363     
11364     
11365     
11366     
11367     
11368      <p>For precipitation processes PALM uses a simplified Kessler
11369scheme. This scheme only considers the
11370so-called autoconversion, that means the generation of rain water by
11371coagulation of cloud drops among themselves. Precipitation begins and
11372is immediately removed from the flow as soon as the liquid water
11373content exceeds the critical value of 0.5 g/kg.</p>
11374
11375
11376
11377
11378
11379
11380
11381
11382
11383
11384      </td>
11385
11386
11387
11388
11389
11390
11391
11392
11393
11394
11395    </tr>
11396
11397
11398
11399
11400
11401
11402
11403
11404
11405
11406    <tr><td style="vertical-align: top;"><a name="pt_reference"></a><span style="font-weight: bold;">pt_reference</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><span style="font-style: italic;">use horizontal average as refrence</span></td><td style="vertical-align: top;">Reference temperature to be used in all buoyancy terms (in K).<br><br>By default, the instantaneous horizontal average over the total model domain is used.</td></tr><tr>
11407
11408
11409
11410
11411
11412
11413
11414
11415
11416
11417      <td style="vertical-align: top;">
11418     
11419     
11420     
11421     
11422     
11423     
11424     
11425     
11426     
11427     
11428      <p><a name="pt_surface"></a><b>pt_surface</b></p>
11429
11430
11431
11432
11433
11434
11435
11436
11437
11438
11439      </td>
11440
11441
11442
11443
11444
11445
11446
11447
11448
11449
11450      <td style="vertical-align: top;">R</td>
11451
11452
11453
11454
11455
11456
11457
11458
11459
11460
11461      <td style="vertical-align: top;"><i>300.0</i></td>
11462
11463
11464
11465
11466
11467
11468
11469
11470
11471
11472      <td style="vertical-align: top;">
11473     
11474     
11475     
11476     
11477     
11478     
11479     
11480     
11481     
11482     
11483      <p>Surface potential temperature (in K).&nbsp; </p>
11484
11485
11486
11487
11488
11489
11490
11491
11492
11493
11494     
11495     
11496     
11497     
11498     
11499     
11500     
11501     
11502     
11503     
11504      <p>This parameter assigns the value of the potential temperature
11505pt at the surface (k=0)<b>.</b> Starting from this value, the
11506initial vertical temperature profile is constructed with <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
11507and <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level </a>.
11508This profile is also used for the 1d-model as a stationary profile.</p>
11509
11510
11511
11512
11513
11514
11515
11516
11517
11518
11519      </td>
11520
11521
11522
11523
11524
11525
11526
11527
11528
11529
11530    </tr>
11531
11532
11533
11534
11535
11536
11537
11538
11539
11540
11541    <tr>
11542
11543
11544
11545
11546
11547
11548
11549
11550
11551
11552      <td style="vertical-align: top;">
11553     
11554     
11555     
11556     
11557     
11558     
11559     
11560     
11561     
11562     
11563      <p><a name="pt_surface_initial_change"></a><b>pt_surface_initial</b>
11564      <br>
11565
11566
11567
11568
11569
11570
11571
11572
11573
11574
11575      <b>_change</b></p>
11576
11577
11578
11579
11580
11581
11582
11583
11584
11585
11586      </td>
11587
11588
11589
11590
11591
11592
11593
11594
11595
11596
11597      <td style="vertical-align: top;">R</td>
11598
11599
11600
11601
11602
11603
11604
11605
11606
11607
11608      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
11609
11610
11611
11612
11613
11614
11615
11616
11617
11618
11619      </td>
11620
11621
11622
11623
11624
11625
11626
11627
11628
11629
11630      <td style="vertical-align: top;">
11631     
11632     
11633     
11634     
11635     
11636     
11637     
11638     
11639     
11640     
11641      <p>Change in surface temperature to be made at the beginning of
11642the 3d run
11643(in K).&nbsp; </p>
11644
11645
11646
11647
11648
11649
11650
11651
11652
11653
11654     
11655     
11656     
11657     
11658     
11659     
11660     
11661     
11662     
11663     
11664      <p>If <b>pt_surface_initial_change</b> is set to a non-zero
11665value, the near surface sensible heat flux is not allowed to be given
11666simultaneously (see <a href="#surface_heatflux">surface_heatflux</a>).</p>
11667
11668
11669
11670
11671
11672
11673
11674
11675
11676
11677      </td>
11678
11679
11680
11681
11682
11683
11684
11685
11686
11687
11688    </tr>
11689
11690
11691
11692
11693
11694
11695
11696
11697
11698
11699    <tr>
11700
11701
11702
11703
11704
11705
11706
11707
11708
11709
11710      <td style="vertical-align: top;">
11711     
11712     
11713     
11714     
11715     
11716     
11717     
11718     
11719     
11720     
11721      <p><a name="pt_vertical_gradient"></a><b>pt_vertical_gradient</b></p>
11722
11723
11724
11725
11726
11727
11728
11729
11730
11731
11732      </td>
11733
11734
11735
11736
11737
11738
11739
11740
11741
11742
11743      <td style="vertical-align: top;">R (10)</td>
11744
11745
11746
11747
11748
11749
11750
11751
11752
11753
11754      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
11755
11756
11757
11758
11759
11760
11761
11762
11763
11764
11765      <td style="vertical-align: top;">
11766     
11767     
11768     
11769     
11770     
11771     
11772     
11773     
11774     
11775     
11776      <p>Temperature gradient(s) of the initial temperature profile (in
11777K
11778/ 100 m).&nbsp; </p>
11779
11780
11781
11782
11783
11784
11785
11786
11787
11788
11789     
11790     
11791     
11792     
11793     
11794     
11795     
11796     
11797     
11798     
11799      <p>This temperature gradient holds starting from the height&nbsp;
11800level defined by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>
11801(precisely: for all uv levels k where zu(k) &gt;
11802pt_vertical_gradient_level,
11803pt_init(k) is set: pt_init(k) = pt_init(k-1) + dzu(k) * <b>pt_vertical_gradient</b>)
11804up to the top boundary or up to the next height level defined
11805by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>.
11806A total of 10 different gradients for 11 height intervals (10 intervals
11807if <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>(1)
11808= <i>0.0</i>) can be assigned. The surface temperature is assigned via
11809      <a href="#pt_surface">pt_surface</a>.&nbsp; </p>
11810
11811
11812
11813
11814
11815
11816
11817
11818
11819
11820     
11821     
11822     
11823     
11824     
11825     
11826     
11827     
11828     
11829     
11830      <p>Example:&nbsp; </p>
11831
11832
11833
11834
11835
11836
11837
11838
11839
11840
11841     
11842     
11843     
11844     
11845     
11846     
11847     
11848     
11849     
11850     
11851      <ul>
11852
11853
11854
11855
11856
11857
11858
11859
11860
11861
11862       
11863       
11864       
11865       
11866       
11867       
11868       
11869       
11870       
11871       
11872        <p><b>pt_vertical_gradient</b> = <i>1.0</i>, <i>0.5</i>,&nbsp;
11873        <br>
11874
11875
11876
11877
11878
11879
11880
11881
11882
11883
11884        <b>pt_vertical_gradient_level</b> = <i>500.0</i>, <i>1000.0</i>,</p>
11885
11886
11887
11888
11889
11890
11891
11892
11893
11894
11895     
11896     
11897     
11898     
11899     
11900     
11901     
11902     
11903     
11904     
11905      </ul>
11906
11907
11908
11909
11910
11911
11912
11913
11914
11915
11916     
11917     
11918     
11919     
11920     
11921     
11922     
11923     
11924     
11925     
11926      <p>That defines the temperature profile to be neutrally
11927stratified
11928up to z = 500.0 m with a temperature given by <a href="#pt_surface">pt_surface</a>.
11929For 500.0 m &lt; z &lt;= 1000.0 m the temperature gradient is 1.0 K /
11930100 m and for z &gt; 1000.0 m up to the top boundary it is
119310.5 K / 100 m (it is assumed that the assigned height levels correspond
11932with uv levels). </p>
11933
11934
11935
11936
11937
11938
11939
11940
11941
11942
11943      </td>
11944
11945
11946
11947
11948
11949
11950
11951
11952
11953
11954    </tr>
11955
11956
11957
11958
11959
11960
11961
11962
11963
11964
11965    <tr>
11966
11967
11968
11969
11970
11971
11972
11973
11974
11975
11976      <td style="vertical-align: top;">
11977     
11978     
11979     
11980     
11981     
11982     
11983     
11984     
11985     
11986     
11987      <p><a name="pt_vertical_gradient_level"></a><b>pt_vertical_gradient</b>
11988      <br>
11989
11990
11991
11992
11993
11994
11995
11996
11997
11998
11999      <b>_level</b></p>
12000
12001
12002
12003
12004
12005
12006
12007
12008
12009
12010      </td>
12011
12012
12013
12014
12015
12016
12017
12018
12019
12020
12021      <td style="vertical-align: top;">R (10)</td>
12022
12023
12024
12025
12026
12027
12028
12029
12030
12031
12032      <td style="vertical-align: top;">
12033     
12034     
12035     
12036     
12037     
12038     
12039     
12040     
12041     
12042     
12043      <p><i>10 *</i>&nbsp; <span style="font-style: italic;">0.0</span><br>
12044
12045
12046
12047
12048
12049
12050
12051
12052
12053
12054      </p>
12055
12056
12057
12058
12059
12060
12061
12062
12063
12064
12065      </td>
12066
12067
12068
12069
12070
12071
12072
12073
12074
12075
12076      <td style="vertical-align: top;">
12077     
12078     
12079     
12080     
12081     
12082     
12083     
12084     
12085     
12086     
12087      <p>Height level from which on the temperature gradient defined by
12088      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
12089is effective (in m).&nbsp; </p>
12090
12091
12092
12093
12094
12095
12096
12097
12098
12099
12100     
12101     
12102     
12103     
12104     
12105     
12106     
12107     
12108     
12109     
12110      <p>The height levels are to be assigned in ascending order. The
12111default values result in a neutral stratification regardless of the
12112values of <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
12113(unless the top boundary of the model is higher than 100000.0 m).
12114For the piecewise construction of temperature profiles see <a href="#pt_vertical_gradient">pt_vertical_gradient</a>.</p>
12115
12116
12117
12118
12119
12120
12121
12122
12123
12124
12125      </td>
12126
12127
12128
12129
12130
12131
12132
12133
12134
12135
12136    </tr>
12137
12138
12139
12140
12141
12142
12143
12144
12145
12146
12147    <tr>
12148
12149
12150
12151
12152
12153
12154
12155
12156
12157
12158      <td style="vertical-align: top;">
12159     
12160     
12161     
12162     
12163     
12164     
12165     
12166     
12167     
12168     
12169      <p><a name="q_surface"></a><b>q_surface</b></p>
12170
12171
12172
12173
12174
12175
12176
12177
12178
12179
12180      </td>
12181
12182
12183
12184
12185
12186
12187
12188
12189
12190
12191      <td style="vertical-align: top;">R</td>
12192
12193
12194
12195
12196
12197
12198
12199
12200
12201
12202      <td style="vertical-align: top;"><i>0.0</i></td>
12203
12204
12205
12206
12207
12208
12209
12210
12211
12212
12213      <td style="vertical-align: top;">
12214     
12215     
12216     
12217     
12218     
12219     
12220     
12221     
12222     
12223     
12224      <p>Surface specific humidity / total water content (kg/kg).&nbsp;
12225      </p>
12226
12227
12228
12229
12230
12231
12232
12233
12234
12235
12236     
12237     
12238     
12239     
12240     
12241     
12242     
12243     
12244     
12245     
12246      <p>This parameter assigns the value of the specific humidity q at
12247the surface (k=0).&nbsp; Starting from this value, the initial humidity
12248profile is constructed with&nbsp; <a href="#q_vertical_gradient">q_vertical_gradient</a>
12249and <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
12250This profile is also used for the 1d-model as a stationary profile.</p>
12251
12252
12253
12254
12255
12256
12257
12258
12259
12260
12261      </td>
12262
12263
12264
12265
12266
12267
12268
12269
12270
12271
12272    </tr>
12273
12274
12275
12276
12277
12278
12279
12280
12281
12282
12283    <tr>
12284
12285
12286
12287
12288
12289
12290
12291
12292
12293
12294      <td style="vertical-align: top;">
12295     
12296     
12297     
12298     
12299     
12300     
12301     
12302     
12303     
12304     
12305      <p><a name="q_surface_initial_change"></a><b>q_surface_initial</b>
12306      <br>
12307
12308
12309
12310
12311
12312
12313
12314
12315
12316
12317      <b>_change</b></p>
12318
12319
12320
12321
12322
12323
12324
12325
12326
12327
12328      </td>
12329
12330
12331
12332
12333
12334
12335
12336
12337
12338
12339      <td style="vertical-align: top;">R<br>
12340
12341
12342
12343
12344
12345
12346
12347
12348
12349
12350      </td>
12351
12352
12353
12354
12355
12356
12357
12358
12359
12360
12361      <td style="vertical-align: top;"><i>0.0</i></td>
12362
12363
12364
12365
12366
12367
12368
12369
12370
12371
12372      <td style="vertical-align: top;">
12373     
12374     
12375     
12376     
12377     
12378     
12379     
12380     
12381     
12382     
12383      <p>Change in surface specific humidity / total water content to
12384be made at the beginning
12385of the 3d run (kg/kg).&nbsp; </p>
12386
12387
12388
12389
12390
12391
12392
12393
12394
12395
12396     
12397     
12398     
12399     
12400     
12401     
12402     
12403     
12404     
12405     
12406      <p>If <b>q_surface_initial_change</b><i> </i>is set to a
12407non-zero value the
12408near surface latent heat flux (water flux) is not allowed to be given
12409simultaneously (see <a href="#surface_waterflux">surface_waterflux</a>).</p>
12410
12411
12412
12413
12414
12415
12416
12417
12418
12419
12420      </td>
12421
12422
12423
12424
12425
12426
12427
12428
12429
12430
12431    </tr>
12432
12433
12434
12435
12436
12437
12438
12439
12440
12441
12442    <tr>
12443
12444
12445
12446
12447
12448
12449
12450
12451
12452
12453      <td style="vertical-align: top;">
12454     
12455     
12456     
12457     
12458     
12459     
12460     
12461     
12462     
12463     
12464      <p><a name="q_vertical_gradient"></a><b>q_vertical_gradient</b></p>
12465
12466
12467
12468
12469
12470
12471
12472
12473
12474
12475      </td>
12476
12477
12478
12479
12480
12481
12482
12483
12484
12485
12486      <td style="vertical-align: top;">R (10)</td>
12487
12488
12489
12490
12491
12492
12493
12494
12495
12496
12497      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
12498
12499
12500
12501
12502
12503
12504
12505
12506
12507
12508      <td style="vertical-align: top;">
12509     
12510     
12511     
12512     
12513     
12514     
12515     
12516     
12517     
12518     
12519      <p>Humidity gradient(s) of the initial humidity profile
12520(in 1/100 m).&nbsp; </p>
12521
12522
12523
12524
12525
12526
12527
12528
12529
12530
12531     
12532     
12533     
12534     
12535     
12536     
12537     
12538     
12539     
12540     
12541      <p>This humidity gradient holds starting from the height
12542level&nbsp; defined by <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>
12543(precisely: for all uv levels k, where zu(k) &gt;
12544q_vertical_gradient_level,
12545q_init(k) is set: q_init(k) = q_init(k-1) + dzu(k) * <b>q_vertical_gradient</b>)
12546up to the top boundary or up to the next height level defined
12547by <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
12548A total of 10 different gradients for 11 height intervals (10 intervals
12549if <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>(1)
12550= <i>0.0</i>) can be asigned. The surface humidity is assigned
12551via <a href="#q_surface">q_surface</a>. </p>
12552
12553
12554
12555
12556
12557
12558
12559
12560
12561
12562     
12563     
12564     
12565     
12566     
12567     
12568     
12569     
12570     
12571     
12572      <p>Example:&nbsp; </p>
12573
12574
12575
12576
12577
12578
12579
12580
12581
12582
12583     
12584     
12585     
12586     
12587     
12588     
12589     
12590     
12591     
12592     
12593      <ul>
12594
12595
12596
12597
12598
12599
12600
12601
12602
12603
12604       
12605       
12606       
12607       
12608       
12609       
12610       
12611       
12612       
12613       
12614        <p><b>q_vertical_gradient</b> = <i>0.001</i>, <i>0.0005</i>,&nbsp;
12615        <br>
12616
12617
12618
12619
12620
12621
12622
12623
12624
12625
12626        <b>q_vertical_gradient_level</b> = <i>500.0</i>, <i>1000.0</i>,</p>
12627
12628
12629
12630
12631
12632
12633
12634
12635
12636
12637     
12638     
12639     
12640     
12641     
12642     
12643     
12644     
12645     
12646     
12647      </ul>
12648
12649
12650
12651
12652
12653
12654
12655
12656
12657
12658That defines the humidity to be constant with height up to z =
12659500.0
12660m with a
12661value given by <a href="#q_surface">q_surface</a>.
12662For 500.0 m &lt; z &lt;= 1000.0 m the humidity gradient is 0.001 / 100
12663m and for z &gt; 1000.0 m up to the top boundary it is
126640.0005 / 100 m (it is assumed that the assigned height levels
12665correspond with uv
12666levels). </td>
12667
12668
12669
12670
12671
12672
12673
12674
12675
12676
12677    </tr>
12678
12679
12680
12681
12682
12683
12684
12685
12686
12687
12688    <tr>
12689
12690
12691
12692
12693
12694
12695
12696
12697
12698
12699      <td style="vertical-align: top;">
12700     
12701     
12702     
12703     
12704     
12705     
12706     
12707     
12708     
12709     
12710      <p><a name="q_vertical_gradient_level"></a><b>q_vertical_gradient</b>
12711      <br>
12712
12713
12714
12715
12716
12717
12718
12719
12720
12721
12722      <b>_level</b></p>
12723
12724
12725
12726
12727
12728
12729
12730
12731
12732
12733      </td>
12734
12735
12736
12737
12738
12739
12740
12741
12742
12743
12744      <td style="vertical-align: top;">R (10)</td>
12745
12746
12747
12748
12749
12750
12751
12752
12753
12754
12755      <td style="vertical-align: top;">
12756     
12757     
12758     
12759     
12760     
12761     
12762     
12763     
12764     
12765     
12766      <p><i>10 *</i>&nbsp; <i>0.0</i></p>
12767
12768
12769
12770
12771
12772
12773
12774
12775
12776
12777      </td>
12778
12779
12780
12781
12782
12783
12784
12785
12786
12787
12788      <td style="vertical-align: top;">
12789     
12790     
12791     
12792     
12793     
12794     
12795     
12796     
12797     
12798     
12799      <p>Height level from which on the moisture gradient defined by <a href="#q_vertical_gradient">q_vertical_gradient</a>
12800is effective (in m).&nbsp; </p>
12801
12802
12803
12804
12805
12806
12807
12808
12809
12810
12811     
12812     
12813     
12814     
12815     
12816     
12817     
12818     
12819     
12820     
12821      <p>The height levels are to be assigned in ascending order. The
12822default values result in a humidity constant with height regardless of
12823the values of <a href="#q_vertical_gradient">q_vertical_gradient</a>
12824(unless the top boundary of the model is higher than 100000.0 m). For
12825the piecewise construction of humidity profiles see <a href="#q_vertical_gradient">q_vertical_gradient</a>.</p>
12826
12827
12828
12829
12830
12831
12832
12833
12834
12835
12836      </td>
12837
12838
12839
12840
12841
12842
12843
12844
12845
12846
12847    </tr>
12848
12849
12850
12851
12852
12853
12854
12855
12856
12857
12858    <tr>
12859
12860
12861
12862
12863
12864
12865
12866
12867
12868
12869      <td style="vertical-align: top;">
12870     
12871     
12872     
12873     
12874     
12875     
12876     
12877     
12878     
12879     
12880      <p><a name="radiation"></a><b>radiation</b></p>
12881
12882
12883
12884
12885
12886
12887
12888
12889
12890
12891      </td>
12892
12893
12894
12895
12896
12897
12898
12899
12900
12901
12902      <td style="vertical-align: top;">L</td>
12903
12904
12905
12906
12907
12908
12909
12910
12911
12912
12913      <td style="vertical-align: top;"><i>.F.</i></td>
12914
12915
12916
12917
12918
12919
12920
12921
12922
12923
12924      <td style="vertical-align: top;">
12925     
12926     
12927     
12928     
12929     
12930     
12931     
12932     
12933     
12934     
12935      <p>Parameter to switch on longwave radiation cooling at
12936cloud-tops.&nbsp; </p>
12937
12938
12939
12940
12941
12942
12943
12944
12945
12946
12947     
12948     
12949     
12950     
12951     
12952     
12953     
12954     
12955     
12956     
12957      <p>Long-wave radiation processes are parameterized by the
12958effective emissivity, which considers only the absorption and emission
12959of long-wave radiation at cloud droplets. The radiation scheme can be
12960used only with <a href="#cloud_physics">cloud_physics</a>
12961= .TRUE. .</p>
12962
12963
12964
12965
12966
12967
12968
12969
12970
12971
12972      </td>
12973
12974
12975
12976
12977
12978
12979
12980
12981
12982
12983    </tr>
12984
12985
12986
12987
12988
12989
12990
12991
12992
12993
12994    <tr>
12995
12996
12997
12998
12999
13000
13001
13002
13003
13004
13005      <td style="vertical-align: top;">
13006     
13007     
13008     
13009     
13010     
13011     
13012     
13013     
13014     
13015     
13016      <p><a name="random_generator"></a><b>random_generator</b></p>
13017
13018
13019
13020
13021
13022
13023
13024
13025
13026
13027      </td>
13028
13029
13030
13031
13032
13033
13034
13035
13036
13037
13038      <td style="vertical-align: top;">C * 20</td>
13039
13040
13041
13042
13043
13044
13045
13046
13047
13048
13049      <td style="vertical-align: top;">
13050     
13051     
13052     
13053     
13054     
13055     
13056     
13057     
13058     
13059     
13060      <p><i>'numerical</i><br>
13061
13062
13063
13064
13065
13066
13067
13068
13069
13070
13071      <i>recipes'</i></p>
13072
13073
13074
13075
13076
13077
13078
13079
13080
13081
13082      </td>
13083
13084
13085
13086
13087
13088
13089
13090
13091
13092
13093      <td style="vertical-align: top;">
13094     
13095     
13096     
13097     
13098     
13099     
13100     
13101     
13102     
13103     
13104      <p>Random number generator to be used for creating uniformly
13105distributed random numbers. <br>
13106
13107
13108
13109
13110
13111
13112
13113
13114
13115
13116      </p>
13117
13118
13119
13120
13121
13122
13123
13124
13125
13126
13127     
13128     
13129     
13130     
13131     
13132     
13133     
13134     
13135     
13136     
13137      <p>It is used if random perturbations are to be imposed on the
13138velocity field or on the surface heat flux field (see <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>
13139and <a href="chapter_4.2.html#random_heatflux">random_heatflux</a>).
13140By default, the "Numerical Recipes" random number generator is used.
13141This one provides exactly the same order of random numbers on all
13142different machines and should be used in particular for comparison runs.<br>
13143
13144
13145
13146
13147
13148
13149
13150
13151
13152
13153      <br>
13154
13155
13156
13157
13158
13159
13160
13161
13162
13163
13164Besides, a system-specific generator is available ( <b>random_generator</b>
13165= <i>'system-specific')</i> which should particularly be used for runs
13166on vector parallel computers (NEC), because the default generator
13167cannot be vectorized and therefore significantly drops down the code
13168performance on these machines.<br>
13169
13170
13171
13172
13173
13174
13175
13176
13177
13178
13179      </p>
13180
13181
13182
13183
13184
13185
13186
13187
13188
13189
13190      <span style="font-weight: bold;">Note:</span><br>
13191
13192
13193
13194
13195
13196
13197
13198
13199
13200
13201Results from two otherwise identical model runs will not be comparable
13202one-to-one if they used different random number generators.</td>
13203
13204
13205
13206
13207
13208
13209
13210
13211
13212
13213    </tr>
13214
13215
13216
13217
13218
13219
13220
13221
13222
13223
13224    <tr>
13225
13226
13227
13228
13229
13230
13231
13232
13233
13234
13235      <td style="vertical-align: top;">
13236     
13237     
13238     
13239     
13240     
13241     
13242     
13243     
13244     
13245     
13246      <p><a name="random_heatflux"></a><b>random_heatflux</b></p>
13247
13248
13249
13250
13251
13252
13253
13254
13255
13256
13257      </td>
13258
13259
13260
13261
13262
13263
13264
13265
13266
13267
13268      <td style="vertical-align: top;">L</td>
13269
13270
13271
13272
13273
13274
13275
13276
13277
13278
13279      <td style="vertical-align: top;"><i>.F.</i></td>
13280
13281
13282
13283
13284
13285
13286
13287
13288
13289
13290      <td style="vertical-align: top;">
13291     
13292     
13293     
13294     
13295     
13296     
13297     
13298     
13299     
13300     
13301      <p>Parameter to impose random perturbations on the internal two-dimensional near surface heat flux field <span style="font-style: italic;">shf</span>. <br>
13302
13303
13304
13305
13306
13307
13308
13309
13310
13311
13312      </p>
13313
13314
13315
13316
13317
13318
13319
13320
13321
13322
13323If a near surface heat flux is used as bottom boundary
13324condition (see <a href="#surface_heatflux">surface_heatflux</a>),
13325it is by default assumed to be horizontally homogeneous. Random
13326perturbations can be imposed on the internal two-dimensional&nbsp;heat flux field <span style="font-style: italic;">shf</span> by assigning <b>random_heatflux</b>
13327= <i>.T.</i>. The disturbed heat flux field is calculated by
13328multiplying the
13329values at each mesh point with a normally distributed random number
13330with a mean value and standard deviation of 1. This is repeated after
13331every timestep.<br>
13332
13333
13334
13335      <br>
13336
13337
13338
13339
13340
13341
13342In case of a non-flat <a href="#topography">topography</a>,&nbsp;assigning <b>random_heatflux</b>
13343= <i>.T.</i> imposes random perturbations on the combined&nbsp;heat
13344flux field <span style="font-style: italic;">shf</span> composed of <a href="#surface_heatflux">surface_heatflux</a> at the bottom surface and <a href="#wall_heatflux">wall_heatflux(0)</a> at the topography top face.</td>
13345
13346
13347
13348
13349
13350
13351
13352
13353
13354
13355    </tr>
13356
13357
13358
13359
13360
13361
13362
13363
13364
13365
13366    <tr>
13367
13368
13369
13370
13371
13372
13373
13374
13375
13376
13377      <td style="vertical-align: top;">
13378     
13379     
13380     
13381     
13382     
13383     
13384     
13385     
13386     
13387     
13388      <p><a name="rif_max"></a><b>rif_max</b></p>
13389
13390
13391
13392
13393
13394
13395
13396
13397
13398
13399      </td>
13400
13401
13402
13403
13404
13405
13406
13407
13408
13409
13410      <td style="vertical-align: top;">R</td>
13411
13412
13413
13414
13415
13416
13417
13418
13419
13420
13421      <td style="vertical-align: top;"><i>1.0</i></td>
13422
13423
13424
13425
13426
13427
13428
13429
13430
13431
13432      <td style="vertical-align: top;">
13433     
13434     
13435     
13436     
13437     
13438     
13439     
13440     
13441     
13442     
13443      <p>Upper limit of the flux-Richardson number.&nbsp; </p>
13444
13445
13446
13447
13448
13449
13450
13451
13452
13453
13454     
13455     
13456     
13457     
13458     
13459     
13460     
13461     
13462     
13463     
13464      <p>With the Prandtl layer switched on (see <a href="#prandtl_layer">prandtl_layer</a>),
13465flux-Richardson numbers (rif) are calculated for z=z<sub>p</sub> (k=1)
13466in the 3d-model (in the 1d model for all heights). Their values in
13467particular determine the
13468values of the friction velocity (1d- and 3d-model) and the values of
13469the eddy diffusivity (1d-model). With small wind velocities at the
13470Prandtl layer top or small vertical wind shears in the 1d-model, rif
13471can take up unrealistic large values. They are limited by an upper (<span style="font-weight: bold;">rif_max</span>) and lower limit (see <a href="#rif_min">rif_min</a>)
13472for the flux-Richardson number. The condition <b>rif_max</b> &gt; <b>rif_min</b>
13473must be met.</p>
13474
13475
13476
13477
13478
13479
13480
13481
13482
13483
13484      </td>
13485
13486
13487
13488
13489
13490
13491
13492
13493
13494
13495    </tr>
13496
13497
13498
13499
13500
13501
13502
13503
13504
13505
13506    <tr>
13507
13508
13509
13510
13511
13512
13513
13514
13515
13516
13517      <td style="vertical-align: top;">
13518     
13519     
13520     
13521     
13522     
13523     
13524     
13525     
13526     
13527     
13528      <p><a name="rif_min"></a><b>rif_min</b></p>
13529
13530
13531
13532
13533
13534
13535
13536
13537
13538
13539      </td>
13540
13541
13542
13543
13544
13545
13546
13547
13548
13549
13550      <td style="vertical-align: top;">R</td>
13551
13552
13553
13554
13555
13556
13557
13558
13559
13560
13561      <td style="vertical-align: top;"><i>- 5.0</i></td>
13562
13563
13564
13565
13566
13567
13568
13569
13570
13571
13572      <td style="vertical-align: top;">
13573     
13574     
13575     
13576     
13577     
13578     
13579     
13580     
13581     
13582     
13583      <p>Lower limit of the flux-Richardson number.&nbsp; </p>
13584
13585
13586
13587
13588
13589
13590
13591
13592
13593
13594     
13595     
13596     
13597     
13598     
13599     
13600     
13601     
13602     
13603     
13604      <p>For further explanations see <a href="#rif_max">rif_max</a>.
13605The condition <b>rif_max</b> &gt; <b>rif_min </b>must be met.</p>
13606
13607
13608
13609
13610
13611
13612
13613
13614
13615
13616      </td>
13617
13618
13619
13620
13621
13622
13623
13624
13625
13626
13627    </tr>
13628
13629
13630
13631
13632
13633
13634
13635
13636
13637
13638    <tr>
13639
13640
13641
13642
13643
13644
13645
13646
13647
13648
13649      <td style="vertical-align: top;">
13650     
13651     
13652     
13653     
13654     
13655     
13656     
13657     
13658     
13659     
13660      <p><a name="roughness_length"></a><b>roughness_length</b></p>
13661
13662
13663
13664
13665
13666
13667
13668
13669
13670
13671      </td>
13672
13673
13674
13675
13676
13677
13678
13679
13680
13681
13682      <td style="vertical-align: top;">R</td>
13683
13684
13685
13686
13687
13688
13689
13690
13691
13692
13693      <td style="vertical-align: top;"><i>0.1</i></td>
13694
13695
13696
13697
13698
13699
13700
13701
13702
13703
13704      <td style="vertical-align: top;">
13705     
13706     
13707     
13708     
13709     
13710     
13711     
13712     
13713     
13714     
13715      <p>Roughness length (in m).&nbsp; </p>
13716
13717
13718
13719
13720
13721
13722
13723
13724
13725
13726     
13727     
13728     
13729     
13730     
13731     
13732     
13733     
13734     
13735     
13736      <p>This parameter is effective only in case that a Prandtl layer
13737is switched
13738on (see <a href="#prandtl_layer">prandtl_layer</a>).</p>
13739
13740
13741
13742
13743
13744
13745
13746
13747
13748
13749      </td>
13750
13751
13752
13753
13754
13755
13756
13757
13758
13759
13760    </tr>
13761
13762
13763
13764
13765
13766
13767
13768
13769
13770
13771    <tr>
13772
13773
13774
13775
13776
13777
13778
13779
13780
13781
13782      <td style="vertical-align: top;">
13783     
13784     
13785     
13786     
13787     
13788     
13789     
13790     
13791     
13792     
13793      <p><a name="scalar_advec"></a><b>scalar_advec</b></p>
13794
13795
13796
13797
13798
13799
13800
13801
13802
13803
13804      </td>
13805
13806
13807
13808
13809
13810
13811
13812
13813
13814
13815      <td style="vertical-align: top;">C * 10</td>
13816
13817
13818
13819
13820
13821
13822
13823
13824
13825
13826      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
13827
13828
13829
13830
13831
13832
13833
13834
13835
13836
13837      <td style="vertical-align: top;">
13838     
13839     
13840     
13841     
13842     
13843     
13844     
13845     
13846     
13847     
13848      <p>Advection scheme to be used for the scalar quantities.&nbsp; </p>
13849
13850
13851
13852
13853
13854
13855
13856
13857
13858
13859     
13860     
13861     
13862     
13863     
13864     
13865     
13866     
13867     
13868     
13869      <p>The user can choose between the following schemes:<br>
13870
13871
13872
13873
13874
13875
13876
13877
13878
13879
13880      </p>
13881
13882
13883
13884
13885
13886
13887
13888
13889
13890
13891     
13892     
13893     
13894     
13895     
13896     
13897     
13898     
13899     
13900     
13901      <p><span style="font-style: italic;">'pw-scheme'</span><br>
13902
13903
13904
13905
13906
13907
13908
13909
13910
13911
13912      </p>
13913
13914
13915
13916
13917
13918
13919
13920
13921
13922
13923     
13924     
13925     
13926     
13927     
13928     
13929     
13930     
13931     
13932     
13933      <div style="margin-left: 40px;">The scheme of Piascek and
13934Williams (1970, J. Comp. Phys., 6,
13935392-405) with central differences in the form C3 is used.<br>
13936
13937
13938
13939
13940
13941
13942
13943
13944
13945
13946If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
13947= <span style="font-style: italic;">'leapfrog+euler'</span> the
13948advection scheme is - for the Euler-timestep - automatically switched
13949to an upstream-scheme. <br>
13950
13951
13952
13953
13954
13955
13956
13957
13958
13959
13960      </div>
13961
13962
13963
13964
13965
13966
13967
13968
13969
13970
13971      <br>
13972
13973
13974
13975
13976
13977
13978
13979
13980
13981
13982     
13983     
13984     
13985     
13986     
13987     
13988     
13989     
13990     
13991     
13992      <p><span style="font-style: italic;">'bc-scheme'</span><br>
13993
13994
13995
13996
13997
13998
13999
14000
14001
14002
14003      </p>
14004
14005
14006
14007
14008
14009
14010
14011
14012
14013
14014     
14015     
14016     
14017     
14018     
14019     
14020     
14021     
14022     
14023     
14024      <div style="margin-left: 40px;">The Bott scheme modified by
14025Chlond (1994, Mon.
14026Wea. Rev., 122, 111-125). This is a conservative monotonous scheme with
14027very small numerical diffusion and therefore very good conservation of
14028scalar flow features. The scheme however, is computationally very
14029expensive both because it is expensive itself and because it does (so
14030far) not allow specific code optimizations (e.g. cache optimization).
14031Choice of this
14032scheme forces the Euler timestep scheme to be used for the scalar
14033quantities. For output of horizontally averaged
14034profiles of the resolved / total heat flux, <a href="chapter_4.2.html#data_output_pr">data_output_pr</a>
14035= <i>'w*pt*BC'</i> / <i>'wptBC' </i>should be used, instead of the
14036standard profiles (<span style="font-style: italic;">'w*pt*'</span>
14037and <span style="font-style: italic;">'wpt'</span>) because these are
14038too inaccurate with this scheme. However, for subdomain analysis (see <a href="#statistic_regions">statistic_regions</a>)
14039exactly the reverse holds: here <i>'w*pt*BC'</i> and <i>'wptBC'</i>
14040show very large errors and should not be used.<br>
14041
14042
14043
14044
14045
14046
14047
14048
14049
14050
14051      <br>
14052
14053
14054
14055
14056
14057
14058
14059
14060
14061
14062This scheme is not allowed for non-cyclic lateral boundary conditions
14063(see <a href="#bc_lr">bc_lr</a>
14064and <a href="#bc_ns">bc_ns</a>).<br>
14065
14066
14067
14068
14069
14070
14071
14072
14073
14074
14075      <br>
14076
14077
14078
14079
14080
14081
14082
14083
14084
14085
14086      </div>
14087
14088
14089
14090
14091
14092
14093
14094
14095
14096
14097      <span style="font-style: italic;">'ups-scheme'</span><br>
14098
14099
14100
14101
14102
14103
14104
14105
14106
14107
14108     
14109     
14110     
14111     
14112     
14113     
14114     
14115     
14116     
14117     
14118      <p style="margin-left: 40px;">The upstream-spline-scheme is used
14119(see Mahrer and Pielke,
141201978: Mon. Wea. Rev., 106, 818-830). In opposite to the Piascek
14121Williams scheme, this is characterized by much better numerical
14122features (less numerical diffusion, better preservation of flux
14123structures, e.g. vortices), but computationally it is much more
14124expensive. In
14125addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
14126= <span style="font-style: italic;">'</span><i>euler'</i>), i.e. the
14127timestep accuracy is only first order. For this reason the advection of
14128momentum (see <a href="#momentum_advec">momentum_advec</a>)
14129should then also be carried out with the upstream-spline scheme,
14130because otherwise the momentum would
14131be subject to large numerical diffusion due to the upstream
14132scheme.&nbsp; </p>
14133
14134
14135
14136
14137
14138
14139
14140
14141
14142
14143     
14144     
14145     
14146     
14147     
14148     
14149     
14150     
14151     
14152     
14153      <p style="margin-left: 40px;">Since the cubic splines used tend
14154to overshoot under
14155certain circumstances, this effect must be adjusted by suitable
14156filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
14157      <a href="#long_filter_factor">long_filter_factor</a>, <a href="#ups_limit_pt">ups_limit_pt</a>, <a href="#ups_limit_u">ups_limit_u</a>,
14158      <a href="#ups_limit_v">ups_limit_v</a>, <a href="#ups_limit_w">ups_limit_w</a>).
14159This is always neccesssary for runs with stable stratification,
14160even if this stratification appears only in parts of the model
14161domain.&nbsp; </p>
14162
14163
14164
14165
14166
14167
14168
14169
14170
14171
14172     
14173     
14174     
14175     
14176     
14177     
14178     
14179     
14180     
14181     
14182      <p style="margin-left: 40px;">With stable stratification the
14183upstream-upline scheme also produces gravity waves with large
14184amplitude, which must be
14185suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
14186
14187
14188
14189
14190
14191
14192
14193
14194
14195
14196      </p>
14197
14198
14199
14200
14201
14202
14203
14204
14205
14206
14207     
14208     
14209     
14210     
14211     
14212     
14213     
14214     
14215     
14216     
14217      <p style="margin-left: 40px;"><span style="font-weight: bold;">Important:
14218      </span>The&nbsp;
14219upstream-spline scheme is not implemented for humidity and passive
14220scalars (see <a href="#moisture">moisture</a>
14221and <a href="#passive_scalar">passive_scalar</a>)
14222and requires the use of a 2d-domain-decomposition. The last conditions
14223severely restricts code optimization on several machines leading to
14224very long execution times! This scheme is also not allowed for
14225non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
14226and <a href="#bc_ns">bc_ns</a>).</p><br>A differing advection scheme can be choosed for the subgrid-scale TKE using parameter <a href="chapter_4.1.html#use_upstream_for_tke">use_upstream_for_tke</a>.</td>
14227
14228
14229
14230
14231
14232
14233
14234
14235
14236
14237    </tr>
14238
14239
14240
14241
14242
14243
14244
14245
14246
14247
14248    <tr>
14249
14250
14251
14252
14253
14254
14255
14256
14257
14258
14259      <td style="vertical-align: top;">
14260     
14261     
14262     
14263     
14264     
14265     
14266     
14267     
14268     
14269     
14270      <p><a name="statistic_regions"></a><b>statistic_regions</b></p>
14271
14272
14273
14274
14275
14276
14277
14278
14279
14280
14281      </td>
14282
14283
14284
14285
14286
14287
14288
14289
14290
14291
14292      <td style="vertical-align: top;">I</td>
14293
14294
14295
14296
14297
14298
14299
14300
14301
14302
14303      <td style="vertical-align: top;"><i>0</i></td>
14304
14305
14306
14307
14308
14309
14310
14311
14312
14313
14314      <td style="vertical-align: top;">
14315     
14316     
14317     
14318     
14319     
14320     
14321     
14322     
14323     
14324     
14325      <p>Number of additional user-defined subdomains for which
14326statistical analysis
14327and corresponding output (profiles, time series) shall be made.&nbsp; </p>
14328
14329
14330
14331
14332
14333
14334
14335
14336
14337
14338     
14339     
14340     
14341     
14342     
14343     
14344     
14345     
14346     
14347     
14348     
14349
14350
14351
14352
14353
14354
14355
14356
14357
14358
14359     
14360     
14361     
14362     
14363     
14364     
14365     
14366     
14367     
14368     
14369      <p>By default, vertical profiles and other statistical quantities
14370are calculated as horizontal and/or volume average of the total model
14371domain. Beyond that, these calculations can also be carried out for
14372subdomains which can be defined using the field <a href="chapter_3.5.3.html">rmask </a>within the user-defined software
14373(see <a href="chapter_3.5.3.html">chapter
143743.5.3</a>). The number of these subdomains is determined with the
14375parameter <b>statistic_regions</b>. Maximum 9 additional subdomains
14376are allowed. The parameter <a href="chapter_4.3.html#region">region</a>
14377can be used to assigned names (identifier) to these subdomains which
14378are then used in the headers
14379of the output files and plots.</p><p>If the default NetCDF output format is selected (see parameter <a href="chapter_4.2.html#data_output_format">data_output_format</a>), data for the total domain and all defined subdomains are output to the same file(s) (<a href="chapter_3.4.html#DATA_1D_PR_NETCDF">DATA_1D_PR_NETCDF</a>, <a href="chapter_3.4.html#DATA_1D_TS_NETCDF">DATA_1D_TS_NETCDF</a>). In case of <span style="font-weight: bold;">statistic_regions</span> &gt; <span style="font-style: italic;">0</span>,
14380data on the file for the different domains can be distinguished by a
14381suffix which is appended to the quantity names. Suffix 0 means data for
14382the total domain, suffix 1 means data for subdomain 1, etc.</p><p>In case of <span style="font-weight: bold;">data_output_format</span> = <span style="font-style: italic;">'profil'</span>, individual local files for profiles (<a href="chapter_3.4.html#PLOT1D_DATA">PLOT1D_DATA</a>)&nbsp;are created for each subdomain. The individual subdomain files differ by their name (the
14383number of the respective subdomain is attached, e.g.
14384PLOT1D_DATA_1). In this case the name of the file with the data of
14385the total domain is PLOT1D_DATA_0. If no subdomains
14386are declared (<b>statistic_regions</b> = <i>0</i>), the name
14387PLOT1D_DATA is used (this must be considered in the
14388respective file connection statements of the <span style="font-weight: bold;">mrun</span> configuration file).</p>
14389
14390
14391
14392
14393
14394
14395
14396
14397
14398
14399      </td>
14400
14401
14402
14403
14404
14405
14406
14407
14408
14409
14410    </tr>
14411
14412
14413
14414
14415
14416
14417
14418
14419
14420
14421    <tr>
14422
14423
14424
14425
14426
14427
14428
14429
14430
14431
14432      <td style="vertical-align: top;">
14433     
14434     
14435     
14436     
14437     
14438     
14439     
14440     
14441     
14442     
14443      <p><a name="surface_heatflux"></a><b>surface_heatflux</b></p>
14444
14445
14446
14447
14448
14449
14450
14451
14452
14453
14454      </td>
14455
14456
14457
14458
14459
14460
14461
14462
14463
14464
14465      <td style="vertical-align: top;">R</td>
14466
14467
14468
14469
14470
14471
14472
14473
14474
14475
14476      <td style="vertical-align: top;"><span style="font-style: italic;">no prescribed<br>
14477heatflux<br>
14478      </span></td>
14479
14480
14481
14482
14483
14484
14485
14486
14487
14488
14489      <td style="vertical-align: top;">
14490     
14491     
14492     
14493     
14494     
14495     
14496     
14497     
14498     
14499     
14500      <p>Kinematic sensible heat flux at the bottom surface (in K m/s).&nbsp; </p>
14501
14502
14503
14504
14505
14506
14507
14508
14509
14510
14511     
14512     
14513     
14514     
14515     
14516     
14517     
14518     
14519     
14520     
14521      <p>If a value is assigned to this parameter, the internal two-dimensional surface heat flux field <span style="font-style: italic;">shf</span> is initialized with the value of <span style="font-weight: bold;">surface_heatflux</span>&nbsp;as bottom (horizontally homogeneous) boundary condition for the
14522temperature equation. This additionally requires that a Neumann
14523condition must be used for the potential temperature (see <a href="#bc_pt_b">bc_pt_b</a>),
14524because otherwise the resolved scale may contribute to
14525the surface flux so that a constant value cannot be guaranteed. Also,
14526changes of the
14527surface temperature (see <a href="#pt_surface_initial_change">pt_surface_initial_change</a>)
14528are not allowed. The parameter <a href="#random_heatflux">random_heatflux</a>
14529can be used to impose random perturbations on the (homogeneous) surface heat
14530flux field <span style="font-style: italic;">shf</span>.&nbsp;</p>
14531
14532
14533
14534     
14535     
14536     
14537      <p>
14538
14539
14540In case of a non-flat <a href="#topography">topography</a>,&nbsp;the internal two-dimensional&nbsp;surface heat
14541flux field <span style="font-style: italic;">shf</span> is initialized with the value of <span style="font-weight: bold;">surface_heatflux</span> at the bottom surface and <a href="#wall_heatflux">wall_heatflux(0)</a> at the topography top face.&nbsp;The parameter<a href="#random_heatflux"> random_heatflux</a>
14542can be used to impose random perturbations on this combined surface heat
14543flux field <span style="font-style: italic;">shf</span>.&nbsp; </p>
14544
14545
14546
14547
14548
14549
14550
14551
14552
14553
14554     
14555     
14556     
14557     
14558     
14559     
14560     
14561     
14562     
14563     
14564      <p>If no surface heat flux is assigned, <span style="font-style: italic;">shf</span> is calculated at each timestep by u<sub>*</sub> * theta<sub>*</sub>
14565(of course only with <a href="#prandtl_layer">prandtl_layer</a> switched on). Here, u<sub>*</sub>
14566and theta<sub>*</sub> are calculated from the Prandtl law assuming
14567logarithmic wind and temperature
14568profiles between k=0 and k=1. In this case a Dirichlet condition (see <a href="#bc_pt_b">bc_pt_b</a>)
14569must be used as bottom boundary condition for the potential temperature.</p><p>See also <a href="#top_heatflux">top_heatflux</a>.</p>
14570
14571
14572
14573
14574
14575
14576
14577
14578
14579
14580      </td>
14581
14582
14583
14584
14585
14586
14587
14588
14589
14590
14591    </tr>
14592
14593
14594
14595
14596
14597
14598
14599
14600
14601
14602    <tr>
14603
14604
14605
14606
14607
14608
14609
14610
14611
14612
14613      <td style="vertical-align: top;">
14614     
14615     
14616     
14617     
14618     
14619     
14620     
14621     
14622     
14623     
14624      <p><a name="surface_pressure"></a><b>surface_pressure</b></p>
14625
14626
14627
14628
14629
14630
14631
14632
14633
14634
14635      </td>
14636
14637
14638
14639
14640
14641
14642
14643
14644
14645
14646      <td style="vertical-align: top;">R</td>
14647
14648
14649
14650
14651
14652
14653
14654
14655
14656
14657      <td style="vertical-align: top;"><i>1013.25</i></td>
14658
14659
14660
14661
14662
14663
14664
14665
14666
14667
14668      <td style="vertical-align: top;">
14669     
14670     
14671     
14672     
14673     
14674     
14675     
14676     
14677     
14678     
14679      <p>Atmospheric pressure at the surface (in hPa).&nbsp; </p>
14680
14681
14682
14683
14684
14685
14686
14687
14688
14689
14690Starting from this surface value, the vertical pressure
14691profile is calculated once at the beginning of the run assuming a
14692neutrally stratified
14693atmosphere. This is needed for
14694converting between the liquid water potential temperature and the
14695potential temperature (see <a href="#cloud_physics">cloud_physics</a><span style="text-decoration: underline;"></span>).</td>
14696
14697
14698
14699
14700
14701
14702
14703
14704
14705
14706    </tr>
14707
14708
14709
14710
14711
14712
14713
14714
14715
14716
14717    <tr>
14718
14719
14720
14721
14722
14723
14724
14725
14726
14727
14728      <td style="vertical-align: top;">
14729     
14730     
14731     
14732     
14733     
14734     
14735     
14736     
14737     
14738     
14739      <p><a name="surface_scalarflux"></a><b>surface_scalarflux</b></p>
14740
14741
14742
14743
14744
14745
14746
14747
14748
14749
14750      </td>
14751
14752
14753
14754
14755
14756
14757
14758
14759
14760
14761      <td style="vertical-align: top;">R</td>
14762
14763
14764
14765
14766
14767
14768
14769
14770
14771
14772      <td style="vertical-align: top;"><i>0.0</i></td>
14773
14774
14775
14776
14777
14778
14779
14780
14781
14782
14783      <td style="vertical-align: top;">
14784     
14785     
14786     
14787     
14788     
14789     
14790     
14791     
14792     
14793     
14794      <p>Scalar flux at the surface (in kg/(m<sup>2</sup> s)).&nbsp; </p>
14795
14796
14797
14798
14799
14800
14801
14802
14803
14804
14805     
14806     
14807     
14808     
14809     
14810     
14811     
14812     
14813     
14814     
14815      <p>If a non-zero value is assigned to this parameter, the
14816respective scalar flux value is used
14817as bottom (horizontally homogeneous) boundary condition for the scalar
14818concentration equation.&nbsp;This additionally requires that a Neumann
14819condition must be used for the scalar concentration&nbsp;(see <a href="#bc_s_b">bc_s_b</a>),
14820because otherwise the resolved scale may contribute to
14821the surface flux so that a constant value cannot be guaranteed. Also,
14822changes of the
14823surface scalar concentration (see <a href="#s_surface_initial_change">s_surface_initial_change</a>)
14824are not allowed. <br>
14825
14826
14827
14828
14829
14830
14831
14832
14833
14834
14835      </p>
14836
14837
14838
14839
14840
14841
14842
14843
14844
14845
14846     
14847     
14848     
14849     
14850     
14851     
14852     
14853     
14854     
14855     
14856      <p>If no surface scalar flux is assigned (<b>surface_scalarflux</b>
14857= <i>0.0</i>),
14858it is calculated at each timestep by u<sub>*</sub> * s<sub>*</sub>
14859(of course only with Prandtl layer switched on). Here, s<sub>*</sub>
14860is calculated from the Prandtl law assuming a logarithmic scalar
14861concentration
14862profile between k=0 and k=1. In this case a Dirichlet condition (see <a href="#bc_s_b">bc_s_b</a>)
14863must be used as bottom boundary condition for the scalar concentration.</p>
14864
14865
14866
14867
14868
14869
14870
14871
14872
14873
14874      </td>
14875
14876
14877
14878
14879
14880
14881
14882
14883
14884
14885    </tr>
14886
14887
14888
14889
14890
14891
14892
14893
14894
14895
14896    <tr>
14897
14898
14899
14900
14901
14902
14903
14904
14905
14906
14907      <td style="vertical-align: top;">
14908     
14909     
14910     
14911     
14912     
14913     
14914     
14915     
14916     
14917     
14918      <p><a name="surface_waterflux"></a><b>surface_waterflux</b></p>
14919
14920
14921
14922
14923
14924
14925
14926
14927
14928
14929      </td>
14930
14931
14932
14933
14934
14935
14936
14937
14938
14939
14940      <td style="vertical-align: top;">R</td>
14941
14942
14943
14944
14945
14946
14947
14948
14949
14950
14951      <td style="vertical-align: top;"><i>0.0</i></td>
14952
14953
14954
14955
14956
14957
14958
14959
14960
14961
14962      <td style="vertical-align: top;">
14963     
14964     
14965     
14966     
14967     
14968     
14969     
14970     
14971     
14972     
14973      <p>Kinematic water flux near the surface (in m/s).&nbsp; </p>
14974
14975
14976
14977
14978
14979
14980
14981
14982
14983
14984     
14985     
14986     
14987     
14988     
14989     
14990     
14991     
14992     
14993     
14994      <p>If a non-zero value is assigned to this parameter, the
14995respective water flux value is used
14996as bottom (horizontally homogeneous) boundary condition for the
14997humidity equation. This additionally requires that a Neumann
14998condition must be used for the specific humidity / total water content
14999(see <a href="#bc_q_b">bc_q_b</a>),
15000because otherwise the resolved scale may contribute to
15001the surface flux so that a constant value cannot be guaranteed. Also,
15002changes of the
15003surface humidity (see <a href="#q_surface_initial_change">q_surface_initial_change</a>)
15004are not allowed.<br>
15005
15006
15007
15008
15009
15010
15011
15012
15013
15014
15015      </p>
15016
15017
15018
15019
15020
15021
15022
15023
15024
15025
15026     
15027     
15028     
15029     
15030     
15031     
15032     
15033     
15034     
15035     
15036      <p>If no surface water flux is assigned (<b>surface_waterflux</b>
15037= <i>0.0</i>),
15038it is calculated at each timestep by u<sub>*</sub> * q<sub>*</sub>
15039(of course only with Prandtl layer switched on). Here, q<sub>*</sub>
15040is calculated from the Prandtl law assuming a logarithmic temperature
15041profile between k=0 and k=1. In this case a Dirichlet condition (see <a href="#bc_q_b">bc_q_b</a>)
15042must be used as the bottom boundary condition for the humidity.</p>
15043
15044
15045
15046
15047
15048
15049
15050
15051
15052
15053      </td>
15054
15055
15056
15057
15058
15059
15060
15061
15062
15063
15064    </tr>
15065
15066
15067
15068
15069
15070
15071
15072
15073
15074
15075    <tr>
15076
15077
15078
15079
15080
15081
15082
15083
15084
15085
15086      <td style="vertical-align: top;">
15087     
15088     
15089     
15090     
15091     
15092     
15093     
15094     
15095     
15096     
15097      <p><a name="s_surface"></a><b>s_surface</b></p>
15098
15099
15100
15101
15102
15103
15104
15105
15106
15107
15108      </td>
15109
15110
15111
15112
15113
15114
15115
15116
15117
15118
15119      <td style="vertical-align: top;">R</td>
15120
15121
15122
15123
15124
15125
15126
15127
15128
15129
15130      <td style="vertical-align: top;"><i>0.0</i></td>
15131
15132
15133
15134
15135
15136
15137
15138
15139
15140
15141      <td style="vertical-align: top;">
15142     
15143     
15144     
15145     
15146     
15147     
15148     
15149     
15150     
15151     
15152      <p>Surface value of the passive scalar (in kg/m<sup>3</sup>).&nbsp;<br>
15153
15154
15155
15156
15157
15158
15159
15160
15161
15162
15163      </p>
15164
15165
15166
15167
15168
15169
15170
15171
15172
15173
15174This parameter assigns the value of the passive scalar s at
15175the surface (k=0)<b>.</b> Starting from this value, the
15176initial vertical scalar concentration profile is constructed with<a href="#s_vertical_gradient">
15177s_vertical_gradient</a> and <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.</td>
15178
15179
15180
15181
15182
15183
15184
15185
15186
15187
15188    </tr>
15189
15190
15191
15192
15193
15194
15195
15196
15197
15198
15199    <tr>
15200
15201
15202
15203
15204
15205
15206
15207
15208
15209
15210      <td style="vertical-align: top;">
15211     
15212     
15213     
15214     
15215     
15216     
15217     
15218     
15219     
15220     
15221      <p><a name="s_surface_initial_change"></a><b>s_surface_initial</b>
15222      <br>
15223
15224
15225
15226
15227
15228
15229
15230
15231
15232
15233      <b>_change</b></p>
15234
15235
15236
15237
15238
15239
15240
15241
15242
15243
15244      </td>
15245
15246
15247
15248
15249
15250
15251
15252
15253
15254
15255      <td style="vertical-align: top;">R</td>
15256
15257
15258
15259
15260
15261
15262
15263
15264
15265
15266      <td style="vertical-align: top;"><i>0.0</i></td>
15267
15268
15269
15270
15271
15272
15273
15274
15275
15276
15277      <td style="vertical-align: top;">
15278     
15279     
15280     
15281     
15282     
15283     
15284     
15285     
15286     
15287     
15288      <p>Change in surface scalar concentration to be made at the
15289beginning of the 3d run (in kg/m<sup>3</sup>).&nbsp; </p>
15290
15291
15292
15293
15294
15295
15296
15297
15298
15299
15300     
15301     
15302     
15303     
15304     
15305     
15306     
15307     
15308     
15309     
15310      <p>If <b>s_surface_initial_change</b><i>&nbsp;</i>is set to a
15311non-zero
15312value, the near surface scalar flux is not allowed to be given
15313simultaneously (see <a href="#surface_scalarflux">surface_scalarflux</a>).</p>
15314
15315
15316
15317
15318
15319
15320
15321
15322
15323
15324      </td>
15325
15326
15327
15328
15329
15330
15331
15332
15333
15334
15335    </tr>
15336
15337
15338
15339
15340
15341
15342
15343
15344
15345
15346    <tr>
15347
15348
15349
15350
15351
15352
15353
15354
15355
15356
15357      <td style="vertical-align: top;">
15358     
15359     
15360     
15361     
15362     
15363     
15364     
15365     
15366     
15367     
15368      <p><a name="s_vertical_gradient"></a><b>s_vertical_gradient</b></p>
15369
15370
15371
15372
15373
15374
15375
15376
15377
15378
15379      </td>
15380
15381
15382
15383
15384
15385
15386
15387
15388
15389
15390      <td style="vertical-align: top;">R (10)</td>
15391
15392
15393
15394
15395
15396
15397
15398
15399
15400
15401      <td style="vertical-align: top;"><i>10 * 0</i><i>.0</i></td>
15402
15403
15404
15405
15406
15407
15408
15409
15410
15411
15412      <td style="vertical-align: top;">
15413     
15414     
15415     
15416     
15417     
15418     
15419     
15420     
15421     
15422     
15423      <p>Scalar concentration gradient(s) of the initial scalar
15424concentration profile (in kg/m<sup>3 </sup>/
15425100 m).&nbsp; </p>
15426
15427
15428
15429
15430
15431
15432
15433
15434
15435
15436     
15437     
15438     
15439     
15440     
15441     
15442     
15443     
15444     
15445     
15446      <p>The scalar gradient holds starting from the height level
15447defined by <a href="#s_vertical_gradient_level">s_vertical_gradient_level
15448      </a>(precisely: for all uv levels k, where zu(k) &gt;
15449s_vertical_gradient_level, s_init(k) is set: s_init(k) = s_init(k-1) +
15450dzu(k) * <b>s_vertical_gradient</b>) up to the top boundary or up to
15451the next height level defined by <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.
15452A total of 10 different gradients for 11 height intervals (10 intervals
15453if <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>(1)
15454= <i>0.0</i>) can be assigned. The surface scalar value is assigned
15455via <a href="#s_surface">s_surface</a>.<br>
15456
15457
15458
15459
15460
15461
15462
15463
15464
15465
15466      </p>
15467
15468
15469
15470
15471
15472
15473
15474
15475
15476
15477     
15478     
15479     
15480     
15481     
15482     
15483     
15484     
15485     
15486     
15487      <p>Example:&nbsp; </p>
15488
15489
15490
15491
15492
15493
15494
15495
15496
15497
15498     
15499     
15500     
15501     
15502     
15503     
15504     
15505     
15506     
15507     
15508      <ul>
15509
15510
15511
15512
15513
15514
15515
15516
15517
15518
15519       
15520       
15521       
15522       
15523       
15524       
15525       
15526       
15527       
15528       
15529        <p><b>s_vertical_gradient</b> = <i>0.1</i>, <i>0.05</i>,&nbsp;
15530        <br>
15531
15532
15533
15534
15535
15536
15537
15538
15539
15540
15541        <b>s_vertical_gradient_level</b> = <i>500.0</i>, <i>1000.0</i>,</p>
15542
15543
15544
15545
15546
15547
15548
15549
15550
15551
15552     
15553     
15554     
15555     
15556     
15557     
15558     
15559     
15560     
15561     
15562      </ul>
15563
15564
15565
15566
15567
15568
15569
15570
15571
15572
15573     
15574     
15575     
15576     
15577     
15578     
15579     
15580     
15581     
15582     
15583      <p>That defines the scalar concentration to be constant with
15584height up to z = 500.0 m with a value given by <a href="#s_surface">s_surface</a>.
15585For 500.0 m &lt; z &lt;= 1000.0 m the scalar gradient is 0.1
15586kg/m<sup>3 </sup>/ 100 m and for z &gt; 1000.0 m up to the top
15587boundary it is 0.05 kg/m<sup>3 </sup>/ 100 m (it is assumed that the
15588assigned height levels
15589correspond with uv
15590levels).</p>
15591
15592
15593
15594
15595
15596
15597
15598
15599
15600
15601      </td>
15602
15603
15604
15605
15606
15607
15608
15609
15610
15611
15612    </tr>
15613
15614
15615
15616
15617
15618
15619
15620
15621
15622
15623    <tr>
15624
15625
15626
15627
15628
15629
15630
15631
15632
15633
15634      <td style="vertical-align: top;">
15635     
15636     
15637     
15638     
15639     
15640     
15641     
15642     
15643     
15644     
15645      <p><a name="s_vertical_gradient_level"></a><b>s_vertical_gradient_</b>
15646      <br>
15647
15648
15649
15650
15651
15652
15653
15654
15655
15656
15657      <b>level</b></p>
15658
15659
15660
15661
15662
15663
15664
15665
15666
15667
15668      </td>
15669
15670
15671
15672
15673
15674
15675
15676
15677
15678
15679      <td style="vertical-align: top;">R (10)</td>
15680
15681
15682
15683
15684
15685
15686
15687
15688
15689
15690      <td style="vertical-align: top;">
15691     
15692     
15693     
15694     
15695     
15696     
15697     
15698     
15699     
15700     
15701      <p><i>10 *</i> <i>0.0</i></p>
15702
15703
15704
15705
15706
15707
15708
15709
15710
15711
15712      </td>
15713
15714
15715
15716
15717
15718
15719
15720
15721
15722
15723      <td style="vertical-align: top;">
15724     
15725     
15726     
15727     
15728     
15729     
15730     
15731     
15732     
15733     
15734      <p>Height level from which on the scalar gradient defined by <a href="#s_vertical_gradient">s_vertical_gradient</a>
15735is effective (in m).&nbsp; </p>
15736
15737
15738
15739
15740
15741
15742
15743
15744
15745
15746     
15747     
15748     
15749     
15750     
15751     
15752     
15753     
15754     
15755     
15756      <p>The height levels are to be assigned in ascending order. The
15757default values result in a scalar concentration constant with height
15758regardless of the values of <a href="#s_vertical_gradient">s_vertical_gradient</a>
15759(unless the top boundary of the model is higher than 100000.0 m). For
15760the
15761piecewise construction of scalar concentration profiles see <a href="#s_vertical_gradient">s_vertical_gradient</a>.</p>
15762
15763
15764
15765
15766
15767
15768
15769
15770
15771
15772      </td>
15773
15774
15775
15776
15777
15778
15779
15780
15781
15782
15783    </tr>
15784
15785
15786
15787
15788
15789
15790
15791
15792
15793
15794    <tr>
15795
15796
15797
15798
15799
15800
15801
15802
15803
15804
15805      <td style="vertical-align: top;">
15806     
15807     
15808     
15809     
15810     
15811     
15812     
15813     
15814     
15815     
15816      <p><a name="timestep_scheme"></a><b>timestep_scheme</b></p>
15817
15818
15819
15820
15821
15822
15823
15824
15825
15826
15827      </td>
15828
15829
15830
15831
15832
15833
15834
15835
15836
15837
15838      <td style="vertical-align: top;">C * 20</td>
15839
15840
15841
15842
15843
15844
15845
15846
15847
15848
15849      <td style="vertical-align: top;">
15850     
15851     
15852     
15853     
15854     
15855     
15856     
15857     
15858     
15859     
15860      <p><i>'runge</i><br>
15861
15862
15863
15864
15865
15866
15867
15868
15869
15870
15871      <i>kutta-3'</i></p>
15872
15873
15874
15875
15876
15877
15878
15879
15880
15881
15882      </td>
15883
15884
15885
15886
15887
15888
15889
15890
15891
15892
15893      <td style="vertical-align: top;">
15894     
15895     
15896     
15897     
15898     
15899     
15900     
15901     
15902     
15903     
15904      <p>Time step scheme to be used for the integration of the prognostic
15905variables.&nbsp; </p>
15906
15907
15908
15909
15910
15911
15912
15913
15914
15915
15916     
15917     
15918     
15919     
15920     
15921     
15922     
15923     
15924     
15925     
15926      <p>The user can choose between the following schemes:<br>
15927
15928
15929
15930
15931
15932
15933
15934
15935
15936
15937      </p>
15938
15939
15940
15941
15942
15943
15944
15945
15946
15947
15948     
15949     
15950     
15951     
15952     
15953     
15954     
15955     
15956     
15957     
15958      <p><span style="font-style: italic;">'runge-kutta-3'</span><br>
15959
15960
15961
15962
15963
15964
15965
15966
15967
15968
15969      </p>
15970
15971
15972
15973
15974
15975
15976
15977
15978
15979
15980     
15981     
15982     
15983     
15984     
15985     
15986     
15987     
15988     
15989     
15990      <div style="margin-left: 40px;">Third order Runge-Kutta scheme.<br>
15991
15992
15993
15994
15995
15996
15997
15998
15999
16000
16001This scheme requires the use of <a href="#momentum_advec">momentum_advec</a>
16002= <a href="#scalar_advec">scalar_advec</a>
16003= '<i>pw-scheme'</i>. Please refer to the&nbsp;<a href="../tec/numerik.heiko/zeitschrittverfahren.pdf">documentation on PALM's time integration schemes&nbsp;(28p., in German)</a> fur further details.<br>
16004
16005
16006
16007
16008
16009
16010
16011
16012
16013
16014      </div>
16015
16016
16017
16018
16019
16020
16021
16022
16023
16024
16025     
16026     
16027     
16028     
16029     
16030     
16031     
16032     
16033     
16034     
16035      <p><span style="font-style: italic;">'runge-kutta-2'</span><br>
16036
16037
16038
16039
16040
16041
16042
16043
16044
16045
16046      </p>
16047
16048
16049
16050
16051
16052
16053
16054
16055
16056
16057     
16058     
16059     
16060     
16061     
16062     
16063     
16064     
16065     
16066     
16067      <div style="margin-left: 40px;">Second order Runge-Kutta scheme.<br>
16068
16069
16070
16071
16072
16073
16074
16075
16076
16077
16078For special features see <b>timestep_scheme</b> = '<i>runge-kutta-3'</i>.<br>
16079
16080
16081
16082
16083
16084
16085
16086
16087
16088
16089      </div>
16090
16091
16092
16093
16094
16095
16096
16097
16098
16099
16100      <br>
16101
16102
16103
16104
16105
16106
16107
16108
16109
16110
16111      <span style="font-style: italic;"><span style="font-style: italic;">'leapfrog'</span><br>
16112
16113
16114
16115
16116
16117
16118
16119
16120
16121
16122      <br>
16123
16124
16125
16126
16127
16128
16129
16130
16131
16132
16133      </span>
16134     
16135     
16136     
16137     
16138     
16139     
16140     
16141     
16142     
16143     
16144      <div style="margin-left: 40px;">Second order leapfrog scheme.<br>
16145
16146
16147
16148
16149
16150
16151
16152
16153
16154
16155Although this scheme requires a constant timestep (because it is
16156centered in time),&nbsp; is even applied in case of changes in
16157timestep. Therefore, only small
16158changes of the timestep are allowed (see <a href="#dt">dt</a>).
16159However, an Euler timestep is always used as the first timestep of an
16160initiali run. When using the Bott-Chlond scheme for scalar advection
16161(see <a href="#scalar_advec">scalar_advec</a>),
16162the prognostic equation for potential temperature will be calculated
16163with the Euler scheme, although the leapfrog scheme is switched
16164on.&nbsp; <br>
16165
16166
16167
16168
16169
16170
16171
16172
16173
16174
16175The leapfrog scheme must not be used together with the upstream-spline
16176scheme for calculating the advection (see <a href="#scalar_advec">scalar_advec</a>
16177= '<i>ups-scheme'</i> and <a href="#momentum_advec">momentum_advec</a>
16178= '<i>ups-scheme'</i>).<br>
16179
16180
16181
16182
16183
16184
16185
16186
16187
16188
16189      </div>
16190
16191
16192
16193
16194
16195
16196
16197
16198
16199
16200      <br>
16201
16202
16203
16204
16205
16206
16207
16208
16209
16210
16211      <span style="font-style: italic;">'</span><span style="font-style: italic;"><span style="font-style: italic;">leapfrog+euler'</span><br>
16212
16213
16214
16215
16216
16217
16218
16219
16220
16221
16222      <br>
16223
16224
16225
16226
16227
16228
16229
16230
16231
16232
16233      </span>
16234     
16235     
16236     
16237     
16238     
16239     
16240     
16241     
16242     
16243     
16244      <div style="margin-left: 40px;">The leapfrog scheme is used, but
16245after each change of a timestep an Euler timestep is carried out.
16246Although this method is theoretically correct (because the pure
16247leapfrog method does not allow timestep changes), the divergence of the
16248velocity field (after applying the pressure solver) may be
16249significantly larger than with <span style="font-style: italic;">'leapfrog'</span>.<br>
16250
16251
16252
16253
16254
16255
16256
16257
16258
16259
16260      </div>
16261
16262
16263
16264
16265
16266
16267
16268
16269
16270
16271      <br>
16272
16273
16274
16275
16276
16277
16278
16279
16280
16281
16282      <span style="font-style: italic;">'euler'</span><br>
16283
16284
16285
16286
16287
16288
16289
16290
16291
16292
16293      <br>
16294
16295
16296
16297
16298
16299
16300
16301
16302
16303
16304     
16305     
16306     
16307     
16308     
16309     
16310     
16311     
16312     
16313     
16314      <div style="margin-left: 40px;">First order Euler scheme.&nbsp; <br>
16315
16316
16317
16318
16319
16320
16321
16322
16323
16324
16325The Euler scheme must be used when treating the advection terms with
16326the upstream-spline scheme (see <a href="#scalar_advec">scalar_advec</a>
16327= <span style="font-style: italic;">'ups-scheme'</span> and <a href="#momentum_advec">momentum_advec</a>
16328= <span style="font-style: italic;">'ups-scheme'</span>).</div>
16329
16330
16331
16332
16333
16334
16335
16336
16337
16338
16339      <br><br>A differing timestep scheme can be choosed for the subgrid-scale TKE using parameter <a href="#use_upstream_for_tke">use_upstream_for_tke</a>.<br>
16340
16341
16342
16343
16344
16345
16346
16347
16348
16349
16350      </td>
16351
16352
16353
16354
16355
16356
16357
16358
16359
16360
16361    </tr>
16362
16363
16364
16365
16366
16367
16368
16369
16370
16371
16372    <tr>
16373
16374
16375
16376
16377
16378
16379
16380
16381
16382      <td style="text-align: left; vertical-align: top;"><span style="font-weight: bold;"><a name="topography"></a></span><span style="font-weight: bold;">topography</span></td>
16383
16384
16385
16386
16387
16388
16389
16390
16391
16392      <td style="vertical-align: top;">C * 40</td>
16393
16394
16395
16396
16397
16398
16399
16400
16401
16402      <td style="vertical-align: top;"><span style="font-style: italic;">'flat'</span></td>
16403
16404
16405
16406
16407
16408
16409
16410
16411
16412      <td>
16413     
16414     
16415     
16416     
16417     
16418     
16419     
16420     
16421     
16422      <p>Topography mode.&nbsp; </p>
16423
16424
16425
16426
16427
16428
16429
16430
16431
16432
16433     
16434     
16435     
16436     
16437     
16438     
16439     
16440     
16441     
16442     
16443      <p>The user can choose between the following modes:<br>
16444
16445
16446
16447
16448
16449
16450
16451
16452
16453
16454      </p>
16455
16456
16457
16458
16459
16460
16461
16462
16463
16464
16465     
16466     
16467     
16468     
16469     
16470     
16471     
16472     
16473     
16474     
16475      <p><span style="font-style: italic;">'flat'</span><br>
16476
16477
16478
16479
16480
16481
16482
16483
16484
16485
16486      </p>
16487
16488
16489
16490
16491
16492
16493
16494
16495
16496
16497     
16498     
16499     
16500     
16501     
16502     
16503     
16504     
16505     
16506     
16507      <div style="margin-left: 40px;">Flat surface.</div>
16508
16509
16510
16511
16512
16513
16514
16515
16516
16517
16518     
16519     
16520     
16521     
16522     
16523     
16524     
16525     
16526     
16527     
16528      <p><span style="font-style: italic;">'single_building'</span><br>
16529
16530
16531
16532
16533
16534
16535
16536
16537
16538
16539      </p>
16540
16541
16542
16543
16544
16545
16546
16547
16548
16549
16550     
16551     
16552     
16553     
16554     
16555     
16556     
16557     
16558     
16559     
16560      <div style="margin-left: 40px;">Flow around&nbsp;a single rectangular building mounted on a flat surface.<br>
16561The building size and location can be specified with the parameters <a href="#building_height">building_height</a>, <a href="#building_length_x">building_length_x</a>, <a href="#building_length_y">building_length_y</a>, <a href="#building_wall_left">building_wall_left</a> and <a href="#building_wall_south">building_wall_south</a>.</div>
16562
16563
16564
16565
16566
16567
16568
16569
16570
16571
16572      <span style="font-style: italic;"></span>
16573     
16574     
16575     
16576     
16577     
16578     
16579     
16580     
16581     
16582      <p><span style="font-style: italic;">'read_from_file'</span><br>
16583
16584
16585
16586
16587
16588
16589
16590
16591
16592
16593      </p>
16594
16595
16596
16597
16598
16599
16600
16601
16602
16603
16604     
16605     
16606     
16607     
16608     
16609     
16610     
16611     
16612     
16613     
16614      <div style="margin-left: 40px;">Flow around arbitrary topography.<br>
16615This mode requires the input file <a href="chapter_3.4.html#TOPOGRAPHY_DATA">TOPOGRAPHY_DATA</a><font color="#000000">. This file contains </font><font color="#000000"><font color="#000000">the&nbsp;</font></font><font color="#000000">arbitrary topography </font><font color="#000000"><font color="#000000">height information</font></font><font color="#000000"> in m. These data&nbsp;<span style="font-style: italic;"></span>must exactly match the horizontal grid.</font>
16616
16617
16618
16619
16620
16621
16622
16623
16624 
16625      </div>
16626
16627
16628
16629
16630
16631
16632
16633
16634
16635
16636      <span style="font-style: italic;"><br>
16637
16638
16639
16640
16641
16642
16643
16644
16645
16646      </span><font color="#000000">
16647Alternatively, the user may add code to the user interface subroutine <a href="chapter_3.5.1.html#user_init_grid">user_init_grid</a> to allow further topography modes.<br>
16648
16649
16650
16651
16652
16653
16654
16655
16656      <br>
16657All non-flat <span style="font-weight: bold;">topography</span> modes </font>require the use of <a href="#momentum_advec">momentum_advec</a>
16658= <a href="#scalar_advec">scalar_advec</a>
16659= '<i>pw-scheme'</i>, <a href="chapter_4.2.html#psolver">psolver</a> = <i>'poisfft'</i> or '<i>poisfft_hybrid'</i>, <i>&nbsp;</i><a href="#alpha_surface">alpha_surface</a> = 0.0, <a href="#bc_lr">bc_lr</a> = <a href="#bc_ns">bc_ns</a> = <span style="font-style: italic;">'cyclic'</span>,&nbsp;<a style="" href="#galilei_transformation">galilei_transformation</a> = <span style="font-style: italic;">.F.</span>,&nbsp;<a href="#cloud_physics">cloud_physics&nbsp;</a> = <span style="font-style: italic;">.F.</span>,&nbsp; <a href="#cloud_droplets">cloud_droplets</a> = <span style="font-style: italic;">.F.</span>,&nbsp; <a href="#moisture">moisture</a> = <span style="font-style: italic;">.F.</span>, and <a href="#prandtl_layer">prandtl_layer</a> = .T..<br>
16660      <font color="#000000"><br>
16661
16662
16663
16664
16665
16666
16667
16668
16669Note that an inclined model domain requires the use of <span style="font-weight: bold;">topography</span> = <span style="font-style: italic;">'flat'</span> and a nonzero </font><a href="#alpha_surface">alpha_surface</a>.</td>
16670
16671
16672
16673
16674
16675
16676
16677
16678
16679    </tr>
16680
16681
16682
16683
16684
16685
16686
16687
16688
16689    <tr><td style="vertical-align: top;"><a name="top_heatflux"></a><span style="font-weight: bold;">top_heatflux</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><span style="font-style: italic;">no prescribed<br>
16690heatflux</span></td><td style="vertical-align: top;"><p>Kinematic sensible heat flux at the top boundary (in K m/s).&nbsp; </p>
16691
16692
16693
16694
16695
16696
16697
16698
16699
16700
16701     
16702     
16703     
16704     
16705     
16706     
16707     
16708     
16709     
16710     
16711      <p>If a value is assigned to this parameter, the internal two-dimensional surface heat flux field <span style="font-family: monospace;">tswst</span> is initialized with the value of <span style="font-weight: bold;">top_heatflux</span>&nbsp;as top (horizontally homogeneous) boundary condition for the
16712temperature equation. This additionally requires that a Neumann
16713condition must be used for the potential temperature (see <a href="chapter_4.1.html#bc_pt_t">bc_pt_t</a>),
16714because otherwise the resolved scale may contribute to
16715the top flux so that a constant value cannot be guaranteed.<span style="font-style: italic;"></span>&nbsp;</p>
16716
16717
16718
16719     
16720     
16721     
16722      <p><span style="font-weight: bold;">Note:</span><br>The application of a top heat flux additionally requires the setting of initial parameter <a href="#use_top_fluxes">use_top_fluxes</a> = .T..<span style="font-style: italic;"></span><span style="font-weight: bold;"></span> </p><p>No Prandtl-layer is available at the top boundary so far.</p><p>See also <a href="#surface_heatflux">surface_heatflux</a>.</p>
16723
16724
16725
16726
16727
16728
16729
16730
16731
16732
16733     
16734     
16735     
16736     
16737     
16738     
16739     
16740     
16741     
16742     
16743      </td></tr><tr>
16744
16745
16746
16747
16748
16749
16750
16751
16752
16753
16754      <td style="vertical-align: top;">
16755     
16756     
16757     
16758     
16759     
16760     
16761     
16762     
16763     
16764     
16765      <p><a name="ug_surface"></a><span style="font-weight: bold;">ug_surface</span></p>
16766
16767
16768
16769
16770
16771
16772
16773
16774
16775
16776      </td>
16777
16778
16779
16780
16781
16782
16783
16784
16785
16786
16787      <td style="vertical-align: top;">R<br>
16788
16789
16790
16791
16792
16793
16794
16795
16796
16797
16798      </td>
16799
16800
16801
16802
16803
16804
16805
16806
16807
16808
16809      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
16810
16811
16812
16813
16814
16815
16816
16817
16818
16819
16820      </td>
16821
16822
16823
16824
16825
16826
16827
16828
16829
16830
16831      <td style="vertical-align: top;">u-component of the geostrophic
16832wind at the surface (in m/s).<br>
16833
16834
16835
16836
16837
16838
16839
16840
16841
16842
16843      <br>
16844
16845
16846
16847
16848
16849
16850
16851
16852
16853
16854This parameter assigns the value of the u-component of the geostrophic
16855wind (ug) at the surface (k=0). Starting from this value, the initial
16856vertical profile of the <br>
16857
16858
16859
16860
16861
16862
16863
16864
16865
16866
16867u-component of the geostrophic wind is constructed with <a href="#ug_vertical_gradient">ug_vertical_gradient</a> and <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>. The
16868profile constructed in that way is used for creating the initial
16869vertical velocity profile of the 3d-model. Either it is applied, as it
16870has been specified by the user (<a href="#initializing_actions">initializing_actions</a>
16871= 'set_constant_profiles') or it is used for calculating a stationary
16872boundary layer wind profile (<a href="#initializing_actions">initializing_actions</a>
16873= 'set_1d-model_profiles'). If ug is constant with height (i.e. ug(k)=<span style="font-weight: bold;">ug_surface</span>) and&nbsp; has a large
16874value, it is recommended to use a Galilei-transformation of the
16875coordinate system, if possible (see <a href="#galilei_transformation">galilei_transformation</a>),
16876in order to obtain larger time steps.<br>
16877
16878
16879
16880
16881
16882
16883
16884
16885
16886
16887      </td>
16888
16889
16890
16891
16892
16893
16894
16895
16896
16897
16898    </tr>
16899
16900
16901
16902
16903
16904
16905
16906
16907
16908
16909    <tr>
16910
16911
16912
16913
16914
16915
16916
16917
16918
16919
16920      <td style="vertical-align: top;">
16921     
16922     
16923     
16924     
16925     
16926     
16927     
16928     
16929     
16930     
16931      <p><a name="ug_vertical_gradient"></a><span style="font-weight: bold;">ug_vertical_gradient</span></p>
16932
16933
16934
16935
16936
16937
16938
16939
16940
16941
16942      </td>
16943
16944
16945
16946
16947
16948
16949
16950
16951
16952
16953      <td style="vertical-align: top;">R(10)<br>
16954
16955
16956
16957
16958
16959
16960
16961
16962
16963
16964      </td>
16965
16966
16967
16968
16969
16970
16971
16972
16973
16974
16975      <td style="vertical-align: top;"><span style="font-style: italic;">10
16976* 0.0</span><br>
16977
16978
16979
16980
16981
16982
16983
16984
16985
16986
16987      </td>
16988
16989
16990
16991
16992
16993
16994
16995
16996
16997
16998      <td style="vertical-align: top;">Gradient(s) of the initial
16999profile of the&nbsp; u-component of the geostrophic wind (in 1/100s).<br>
17000
17001
17002
17003
17004
17005
17006
17007
17008
17009
17010      <br>
17011
17012
17013
17014
17015
17016
17017
17018
17019
17020
17021The gradient holds starting from the height level defined by <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>
17022(precisely: for all uv levels k where zu(k) &gt; <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>,
17023ug(k) is set: ug(k) = ug(k-1) + dzu(k) * <span style="font-weight: bold;">ug_vertical_gradient</span>) up to the top
17024boundary or up to the next height level defined by <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>. A
17025total of 10 different gradients for 11 height intervals (10
17026intervals&nbsp; if <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>(1)
17027= 0.0) can be assigned. The surface geostrophic wind is assigned by <a href="#ug_surface">ug_surface</a>. <br>
17028
17029
17030
17031
17032
17033
17034
17035
17036
17037
17038      </td>
17039
17040
17041
17042
17043
17044
17045
17046
17047
17048
17049    </tr>
17050
17051
17052
17053
17054
17055
17056
17057
17058
17059
17060    <tr>
17061
17062
17063
17064
17065
17066
17067
17068
17069
17070
17071      <td style="vertical-align: top;">
17072     
17073     
17074     
17075     
17076     
17077     
17078     
17079     
17080     
17081     
17082      <p><a name="ug_vertical_gradient_level"></a><span style="font-weight: bold;">ug_vertical_gradient_level</span></p>
17083
17084
17085
17086
17087
17088
17089
17090
17091
17092
17093      </td>
17094
17095
17096
17097
17098
17099
17100
17101
17102
17103
17104      <td style="vertical-align: top;">R(10)<br>
17105
17106
17107
17108
17109
17110
17111
17112
17113
17114
17115      </td>
17116
17117
17118
17119
17120
17121
17122
17123
17124
17125
17126      <td style="vertical-align: top;"><span style="font-style: italic;">10
17127* 0.0</span><br>
17128
17129
17130
17131
17132
17133
17134
17135
17136
17137
17138      </td>
17139
17140
17141
17142
17143
17144
17145
17146
17147
17148
17149      <td style="vertical-align: top;">Height level from which on the
17150gradient defined by <a href="#ug_vertical_gradient">ug_vertical_gradient</a>
17151is effective (in m).<br>
17152
17153
17154
17155
17156
17157
17158
17159
17160
17161
17162      <br>
17163
17164
17165
17166
17167
17168
17169
17170
17171
17172
17173The height levels are to be assigned in ascending order. For the
17174piecewise construction of a profile of the u-component of the
17175geostrophic wind component (ug) see <a href="#ug_vertical_gradient">ug_vertical_gradient</a>.<br>
17176
17177
17178
17179
17180
17181
17182
17183
17184
17185
17186      </td>
17187
17188
17189
17190
17191
17192
17193
17194
17195
17196
17197    </tr>
17198
17199
17200
17201
17202
17203
17204
17205
17206
17207
17208    <tr>
17209
17210
17211
17212
17213
17214
17215
17216
17217
17218
17219      <td style="vertical-align: top;">
17220     
17221     
17222     
17223     
17224     
17225     
17226     
17227     
17228     
17229     
17230      <p><a name="ups_limit_e"></a><b>ups_limit_e</b></p>
17231
17232
17233
17234
17235
17236
17237
17238
17239
17240
17241      </td>
17242
17243
17244
17245
17246
17247
17248
17249
17250
17251
17252      <td style="vertical-align: top;">R</td>
17253
17254
17255
17256
17257
17258
17259
17260
17261
17262
17263      <td style="vertical-align: top;"><i>0.0</i></td>
17264
17265
17266
17267
17268
17269
17270
17271
17272
17273
17274      <td style="vertical-align: top;">
17275     
17276     
17277     
17278     
17279     
17280     
17281     
17282     
17283     
17284     
17285      <p>Subgrid-scale turbulent kinetic energy difference used as
17286criterion for applying the upstream scheme when upstream-spline
17287advection is switched on (in m<sup>2</sup>/s<sup>2</sup>).
17288&nbsp; </p>
17289
17290
17291
17292
17293
17294
17295
17296
17297
17298
17299     
17300     
17301     
17302     
17303     
17304     
17305     
17306     
17307     
17308     
17309      <p>This variable steers the appropriate treatment of the
17310advection of the subgrid-scale turbulent kinetic energy in case that
17311the uptream-spline scheme is used . For further information see <a href="#ups_limit_pt">ups_limit_pt</a>.&nbsp; </p>
17312
17313
17314
17315
17316
17317
17318
17319
17320
17321
17322     
17323     
17324     
17325     
17326     
17327     
17328     
17329     
17330     
17331     
17332      <p>Only positive values are allowed for <b>ups_limit_e</b>. </p>
17333
17334
17335
17336
17337
17338
17339
17340
17341
17342
17343      </td>
17344
17345
17346
17347
17348
17349
17350
17351
17352
17353
17354    </tr>
17355
17356
17357
17358
17359
17360
17361
17362
17363
17364
17365    <tr>
17366
17367
17368
17369
17370
17371
17372
17373
17374
17375
17376      <td style="vertical-align: top;">
17377     
17378     
17379     
17380     
17381     
17382     
17383     
17384     
17385     
17386     
17387      <p><a name="ups_limit_pt"></a><b>ups_limit_pt</b></p>
17388
17389
17390
17391
17392
17393
17394
17395
17396
17397
17398      </td>
17399
17400
17401
17402
17403
17404
17405
17406
17407
17408
17409      <td style="vertical-align: top;">R</td>
17410
17411
17412
17413
17414
17415
17416
17417
17418
17419
17420      <td style="vertical-align: top;"><i>0.0</i></td>
17421
17422
17423
17424
17425
17426
17427
17428
17429
17430
17431      <td style="vertical-align: top;">
17432     
17433     
17434     
17435     
17436     
17437     
17438     
17439     
17440     
17441     
17442      <p>Temperature difference used as criterion for applying&nbsp;
17443the upstream scheme when upstream-spline advection&nbsp; is switched on
17444(in K).&nbsp; </p>
17445
17446
17447
17448
17449
17450
17451
17452
17453
17454
17455     
17456     
17457     
17458     
17459     
17460     
17461     
17462     
17463     
17464     
17465      <p>This criterion is used if the upstream-spline scheme is
17466switched on (see <a href="#scalar_advec">scalar_advec</a>).<br>
17467
17468
17469
17470
17471
17472
17473
17474
17475
17476
17477If, for a given gridpoint, the absolute temperature difference with
17478respect to the upstream
17479grid point is smaller than the value given for <b>ups_limit_pt</b>,
17480the upstream scheme is used for this gridpoint (by default, the
17481upstream-spline scheme is always used). Reason: in case of a very small
17482upstream gradient, the advection should cause only a very small
17483tendency. However, in such situations the upstream-spline scheme may
17484give wrong tendencies at a
17485grid point due to spline overshooting, if simultaneously the downstream
17486gradient is very large. In such cases it may be more reasonable to use
17487the upstream scheme. The numerical diffusion caused by the upstream
17488schme remains small as long as the upstream gradients are small.<br>
17489
17490
17491
17492
17493
17494
17495
17496
17497
17498
17499      </p>
17500
17501
17502
17503
17504
17505
17506
17507
17508
17509
17510     
17511     
17512     
17513     
17514     
17515     
17516     
17517     
17518     
17519     
17520      <p>The percentage of grid points for which the upstream
17521scheme is actually used, can be output as a time series with respect to
17522the
17523three directions in space with run parameter (see <a href="chapter_4.2.html#dt_dots">dt_dots</a>, the timeseries names in the NetCDF file are <i>'splptx'</i>, <i>'splpty'</i>, <i>'splptz'</i>). The percentage
17524of gridpoints&nbsp; should stay below a certain limit, however, it is
17525not possible to give
17526a general limit, since it depends on the respective flow.&nbsp; </p>
17527
17528
17529
17530
17531
17532
17533
17534
17535
17536
17537     
17538     
17539     
17540     
17541     
17542     
17543     
17544     
17545     
17546     
17547      <p>Only positive values are permitted for <b>ups_limit_pt</b>.<br>
17548
17549
17550
17551
17552
17553
17554
17555
17556
17557
17558      </p>
17559
17560
17561
17562
17563
17564
17565
17566
17567
17568
17569A more effective control of
17570the &ldquo;overshoots&rdquo; can be achieved with parameter <a href="#cut_spline_overshoot">cut_spline_overshoot</a>. </td>
17571
17572
17573
17574
17575
17576
17577
17578
17579
17580
17581    </tr>
17582
17583
17584
17585
17586
17587
17588
17589
17590
17591
17592    <tr>
17593
17594
17595
17596
17597
17598
17599
17600
17601
17602
17603      <td style="vertical-align: top;">
17604     
17605     
17606     
17607     
17608     
17609     
17610     
17611     
17612     
17613     
17614      <p><a name="ups_limit_u"></a><b>ups_limit_u</b></p>
17615
17616
17617
17618
17619
17620
17621
17622
17623
17624
17625      </td>
17626
17627
17628
17629
17630
17631
17632
17633
17634
17635
17636      <td style="vertical-align: top;">R</td>
17637
17638
17639
17640
17641
17642
17643
17644
17645
17646
17647      <td style="vertical-align: top;"><i>0.0</i></td>
17648
17649
17650
17651
17652
17653
17654
17655
17656
17657
17658      <td style="vertical-align: top;">
17659     
17660     
17661     
17662     
17663     
17664     
17665     
17666     
17667     
17668     
17669      <p>Velocity difference (u-component) used as criterion for
17670applying the upstream scheme
17671when upstream-spline advection is switched on (in m/s).&nbsp; </p>
17672
17673
17674
17675
17676
17677
17678
17679
17680
17681
17682     
17683     
17684     
17685     
17686     
17687     
17688     
17689     
17690     
17691     
17692      <p>This variable steers the appropriate treatment of the
17693advection of the u-velocity-component in case that the upstream-spline
17694scheme is used. For further
17695information see <a href="#ups_limit_pt">ups_limit_pt</a>.&nbsp; </p>
17696
17697
17698
17699
17700
17701
17702
17703
17704
17705
17706     
17707     
17708     
17709     
17710     
17711     
17712     
17713     
17714     
17715     
17716      <p>Only positive values are permitted for <b>ups_limit_u</b>.</p>
17717
17718
17719
17720
17721
17722
17723
17724
17725
17726
17727      </td>
17728
17729
17730
17731
17732
17733
17734
17735
17736
17737
17738    </tr>
17739
17740
17741
17742
17743
17744
17745
17746
17747
17748
17749    <tr>
17750
17751
17752
17753
17754
17755
17756
17757
17758
17759
17760      <td style="vertical-align: top;">
17761     
17762     
17763     
17764     
17765     
17766     
17767     
17768     
17769     
17770     
17771      <p><a name="ups_limit_v"></a><b>ups_limit_v</b></p>
17772
17773
17774
17775
17776
17777
17778
17779
17780
17781
17782      </td>
17783
17784
17785
17786
17787
17788
17789
17790
17791
17792
17793      <td style="vertical-align: top;">R</td>
17794
17795
17796
17797
17798
17799
17800
17801
17802
17803
17804      <td style="vertical-align: top;"><i>0.0</i></td>
17805
17806
17807
17808
17809
17810
17811
17812
17813
17814
17815      <td style="vertical-align: top;">
17816     
17817     
17818     
17819     
17820     
17821     
17822     
17823     
17824     
17825     
17826      <p>Velocity difference (v-component) used as criterion for
17827applying the upstream scheme
17828when upstream-spline advection is switched on (in m/s).&nbsp; </p>
17829
17830
17831
17832
17833
17834
17835
17836
17837
17838
17839     
17840     
17841     
17842     
17843     
17844     
17845     
17846     
17847     
17848     
17849      <p>This variable steers the appropriate treatment of the
17850advection of the v-velocity-component in case that the upstream-spline
17851scheme is used. For further
17852information see <a href="#ups_limit_pt">ups_limit_pt</a>.&nbsp; </p>
17853
17854
17855
17856
17857
17858
17859
17860
17861
17862
17863     
17864     
17865     
17866     
17867     
17868     
17869     
17870     
17871     
17872     
17873      <p>Only positive values are permitted for <b>ups_limit_v</b>.</p>
17874
17875
17876
17877
17878
17879
17880
17881
17882
17883
17884      </td>
17885
17886
17887
17888
17889
17890
17891
17892
17893
17894
17895    </tr>
17896
17897
17898
17899
17900
17901
17902
17903
17904
17905
17906    <tr>
17907
17908
17909
17910
17911
17912
17913
17914
17915
17916
17917      <td style="vertical-align: top;">
17918     
17919     
17920     
17921     
17922     
17923     
17924     
17925     
17926     
17927     
17928      <p><a name="ups_limit_w"></a><b>ups_limit_w</b></p>
17929
17930
17931
17932
17933
17934
17935
17936
17937
17938
17939      </td>
17940
17941
17942
17943
17944
17945
17946
17947
17948
17949
17950      <td style="vertical-align: top;">R</td>
17951
17952
17953
17954
17955
17956
17957
17958
17959
17960
17961      <td style="vertical-align: top;"><i>0.0</i></td>
17962
17963
17964
17965
17966
17967
17968
17969
17970
17971
17972      <td style="vertical-align: top;">
17973     
17974     
17975     
17976     
17977     
17978     
17979     
17980     
17981     
17982     
17983      <p>Velocity difference (w-component) used as criterion for
17984applying the upstream scheme
17985when upstream-spline advection is switched on (in m/s).&nbsp; </p>
17986
17987
17988
17989
17990
17991
17992
17993
17994
17995
17996     
17997     
17998     
17999     
18000     
18001     
18002     
18003     
18004     
18005     
18006      <p>This variable steers the appropriate treatment of the
18007advection of the w-velocity-component in case that the upstream-spline
18008scheme is used. For further
18009information see <a href="#ups_limit_pt">ups_limit_pt</a>.&nbsp; </p>
18010
18011
18012
18013
18014
18015
18016
18017
18018
18019
18020     
18021     
18022     
18023     
18024     
18025     
18026     
18027     
18028     
18029     
18030      <p>Only positive values are permitted for <b>ups_limit_w</b>.</p>
18031
18032
18033
18034
18035
18036
18037
18038
18039
18040
18041      </td>
18042
18043
18044
18045
18046
18047
18048
18049
18050
18051
18052    </tr>
18053
18054
18055
18056
18057
18058
18059
18060
18061
18062
18063    <tr>
18064
18065
18066
18067
18068
18069
18070
18071
18072
18073
18074      <td style="vertical-align: top;">
18075     
18076     
18077     
18078     
18079     
18080     
18081     
18082     
18083     
18084     
18085      <p><a name="use_surface_fluxes"></a><b>use_surface_fluxes</b></p>
18086
18087
18088
18089
18090
18091
18092
18093
18094
18095
18096      </td>
18097
18098
18099
18100
18101
18102
18103
18104
18105
18106
18107      <td style="vertical-align: top;">L</td>
18108
18109
18110
18111
18112
18113
18114
18115
18116
18117
18118      <td style="vertical-align: top;"><i>.F.</i></td>
18119
18120
18121
18122
18123
18124
18125
18126
18127
18128
18129      <td style="vertical-align: top;">
18130     
18131     
18132     
18133     
18134     
18135     
18136     
18137     
18138     
18139     
18140      <p>Parameter to steer the treatment of the subgrid-scale vertical
18141fluxes within the diffusion terms at k=1 (bottom boundary).<br>
18142
18143
18144
18145
18146
18147
18148
18149
18150
18151
18152      </p>
18153
18154
18155
18156
18157
18158
18159
18160
18161
18162
18163     
18164     
18165     
18166     
18167     
18168     
18169     
18170     
18171     
18172     
18173      <p>By default, the near-surface subgrid-scale fluxes are
18174parameterized (like in the remaining model domain) using the gradient
18175approach. If <b>use_surface_fluxes</b>
18176= <i>.TRUE.</i>, the user-assigned surface fluxes are used instead
18177(see <a href="#surface_heatflux">surface_heatflux</a>, <a href="#surface_waterflux">surface_waterflux</a>
18178and <a href="#surface_scalarflux">surface_scalarflux</a>) <span style="font-weight: bold;">or</span> the surface fluxes are
18179calculated via the Prandtl layer relation (depends on the bottom
18180boundary conditions, see <a href="#bc_pt_b">bc_pt_b</a>, <a href="#bc_q_b">bc_q_b</a>
18181and <a href="#bc_s_b">bc_s_b</a>).<br>
18182
18183
18184
18185
18186
18187
18188
18189
18190
18191
18192      </p>
18193
18194
18195
18196
18197
18198
18199
18200
18201
18202
18203     
18204     
18205     
18206     
18207     
18208     
18209     
18210     
18211     
18212     
18213      <p><b>use_surface_fluxes</b>
18214is automatically set <i>.TRUE.</i>, if a Prandtl layer is used (see <a href="#prandtl_layer">prandtl_layer</a>).&nbsp; </p>
18215
18216
18217
18218
18219
18220
18221
18222
18223
18224
18225     
18226     
18227     
18228     
18229     
18230     
18231     
18232     
18233     
18234     
18235      <p>The user may prescribe the surface fluxes at the bottom
18236boundary without using a Prandtl layer by setting <span style="font-weight: bold;">use_surface_fluxes</span> = <span style="font-style: italic;">.T.</span> and <span style="font-weight: bold;">prandtl_layer</span> = <span style="font-style: italic;">.F.</span>. If , in this case, the
18237momentum flux (u<sub>*</sub><sup>2</sup>) should also be prescribed,
18238the user must assign an appropriate value within the user-defined code.</p>
18239
18240
18241
18242
18243
18244
18245
18246
18247
18248
18249      </td>
18250
18251
18252
18253
18254
18255
18256
18257
18258
18259
18260    </tr>
18261
18262
18263
18264
18265
18266
18267
18268
18269
18270
18271    <tr><td style="vertical-align: top;"><a name="use_top_fluxes"></a><span style="font-weight: bold;">use_top_fluxes</span></td><td style="vertical-align: top;">L</td><td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td><td style="vertical-align: top;">
18272
18273
18274
18275
18276
18277
18278
18279
18280
18281
18282     
18283     
18284     
18285     
18286     
18287     
18288     
18289     
18290     
18291     
18292     
18293
18294
18295
18296
18297
18298
18299
18300
18301
18302
18303     
18304     
18305     
18306     
18307     
18308     
18309     
18310     
18311     
18312     
18313     
18314
18315
18316
18317
18318
18319
18320
18321
18322
18323
18324     
18325     
18326     
18327     
18328     
18329     
18330     
18331     
18332     
18333     
18334      <p>Parameter to steer the treatment of the subgrid-scale vertical
18335fluxes within the diffusion terms at k=nz (top boundary).</p><p>By default, the fluxes at nz are calculated using the gradient approach. If <b>use_top_fluxes</b>
18336= <i>.TRUE.</i>, the user-assigned top fluxes are used instead
18337(see <a href="chapter_4.1.html#top_heatflux">top_heatflux</a>).</p><p>Currently, only a value for the sensible heatflux can be assigned. In case of <span style="font-weight: bold;">use_top_fluxes</span> = <span style="font-style: italic;">.TRUE.</span>, the latent heat flux at the top will be automatically set to zero.</p></td></tr><tr>
18338
18339
18340
18341
18342
18343
18344
18345
18346
18347
18348      <td style="vertical-align: top;">
18349     
18350     
18351     
18352     
18353     
18354     
18355     
18356     
18357     
18358     
18359      <p><a name="use_ug_for_galilei_tr"></a><b>use_ug_for_galilei_tr</b></p>
18360
18361
18362
18363
18364
18365
18366
18367
18368
18369
18370      </td>
18371
18372
18373
18374
18375
18376
18377
18378
18379
18380
18381      <td style="vertical-align: top;">L</td>
18382
18383
18384
18385
18386
18387
18388
18389
18390
18391
18392      <td style="vertical-align: top;"><i>.T.</i></td>
18393
18394
18395
18396
18397
18398
18399
18400
18401
18402
18403      <td style="vertical-align: top;">
18404     
18405     
18406     
18407     
18408     
18409     
18410     
18411     
18412     
18413     
18414      <p>Switch to determine the translation velocity in case that a
18415Galilean transformation is used.<br>
18416
18417
18418
18419
18420
18421
18422
18423
18424
18425
18426      </p>
18427
18428
18429
18430
18431
18432
18433
18434
18435
18436
18437     
18438     
18439     
18440     
18441     
18442     
18443     
18444     
18445     
18446     
18447      <p>In case of a Galilean transformation (see <a href="#galilei_transformation">galilei_transformation</a>), <b>use_ug_for_galilei_tr</b>
18448= <i>.T.</i>&nbsp; ensures
18449that the coordinate system is translated with the geostrophic windspeed.<br>
18450
18451
18452
18453
18454
18455
18456
18457
18458
18459
18460      </p>
18461
18462
18463
18464
18465
18466
18467
18468
18469
18470
18471     
18472     
18473     
18474     
18475     
18476     
18477     
18478     
18479     
18480     
18481      <p>Alternatively, with <b>use_ug_for_galilei_tr</b> = <i>.F</i>.,
18482the
18483geostrophic wind can be replaced as translation speed by the (volume)
18484averaged velocity. However, in this case the user must be aware of fast
18485growing gravity waves, so this
18486choice is usually not recommended!</p>
18487
18488
18489
18490
18491
18492
18493
18494
18495
18496
18497      </td>
18498
18499
18500
18501
18502
18503
18504
18505
18506
18507
18508    </tr>
18509
18510
18511
18512
18513
18514
18515
18516
18517
18518
18519    <tr><td align="left" valign="top"><a name="use_upstream_for_tke"></a><span style="font-weight: bold;">use_upstream_for_tke</span></td><td align="left" valign="top">L</td><td align="left" valign="top"><span style="font-style: italic;">.F.</span></td><td align="left" valign="top">Parameter to choose the advection/timestep scheme to be used for the subgrid-scale TKE.<br><br>By
18520default, the advection scheme and the timestep scheme to be used for
18521the subgrid-scale TKE are set by the initialization parameters <a href="#scalar_advec">scalar_advec</a> and <a href="#timestep_scheme">timestep_scheme</a>, respectively. <span style="font-weight: bold;">use_upstream_for_tke</span> = <span style="font-style: italic;">.T.</span>
18522forces the Euler-scheme and the upstream-scheme to be used as timestep
18523scheme and advection scheme, respectively. By these methods, the strong
18524(artificial) near-surface vertical gradients of the subgrid-scale TKE
18525are significantly reduced. This is required when subgrid-scale
18526velocities are used for advection of particles (see particle package
18527parameter <a href="chapter_4.2.html#use_sgs_for_particles">use_sgs_for_particles</a>).</td></tr><tr>
18528
18529
18530
18531
18532
18533
18534
18535
18536
18537
18538      <td style="vertical-align: top;">
18539     
18540     
18541     
18542     
18543     
18544     
18545     
18546     
18547     
18548     
18549      <p><a name="vg_surface"></a><span style="font-weight: bold;">vg_surface</span></p>
18550
18551
18552
18553
18554
18555
18556
18557
18558
18559
18560      </td>
18561
18562
18563
18564
18565
18566
18567
18568
18569
18570
18571      <td style="vertical-align: top;">R<br>
18572
18573
18574
18575
18576
18577
18578
18579
18580
18581
18582      </td>
18583
18584
18585
18586
18587
18588
18589
18590
18591
18592
18593      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
18594
18595
18596
18597
18598
18599
18600
18601
18602
18603
18604      </td>
18605
18606
18607
18608
18609
18610
18611
18612
18613
18614
18615      <td style="vertical-align: top;">v-component of the geostrophic
18616wind at the surface (in m/s).<br>
18617
18618
18619
18620
18621
18622
18623
18624
18625
18626
18627      <br>
18628
18629
18630
18631
18632
18633
18634
18635
18636
18637
18638This parameter assigns the value of the v-component of the geostrophic
18639wind (vg) at the surface (k=0). Starting from this value, the initial
18640vertical profile of the <br>
18641
18642
18643
18644
18645
18646
18647
18648
18649
18650
18651v-component of the geostrophic wind is constructed with <a href="#vg_vertical_gradient">vg_vertical_gradient</a> and <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>. The
18652profile
18653constructed in that way is used for creating the initial vertical
18654velocity profile of the 3d-model. Either it is applied, as it has been
18655specified by the user (<a href="#initializing_actions">initializing_actions</a>
18656= 'set_constant_profiles')
18657or it is used for calculating a stationary boundary layer wind profile
18658(<a href="#initializing_actions">initializing_actions</a> =
18659'set_1d-model_profiles'). If vg is constant
18660with height (i.e. vg(k)=<span style="font-weight: bold;">vg_surface</span>)
18661and&nbsp; has a large value, it is
18662recommended to use a Galilei-transformation of the coordinate system,
18663if possible (see <a href="#galilei_transformation">galilei_transformation</a>),
18664in order to obtain larger
18665time steps.</td>
18666
18667
18668
18669
18670
18671
18672
18673
18674
18675
18676    </tr>
18677
18678
18679
18680
18681
18682
18683
18684
18685
18686
18687    <tr>
18688
18689
18690
18691
18692
18693
18694
18695
18696
18697
18698      <td style="vertical-align: top;">
18699     
18700     
18701     
18702     
18703     
18704     
18705     
18706     
18707     
18708     
18709      <p><a name="vg_vertical_gradient"></a><span style="font-weight: bold;">vg_vertical_gradient</span></p>
18710
18711
18712
18713
18714
18715
18716
18717
18718
18719
18720      </td>
18721
18722
18723
18724
18725
18726
18727
18728
18729
18730
18731      <td style="vertical-align: top;">R(10)<br>
18732
18733
18734
18735
18736
18737
18738
18739
18740
18741
18742      </td>
18743
18744
18745
18746
18747
18748
18749
18750
18751
18752
18753      <td style="vertical-align: top;"><span style="font-style: italic;">10
18754* 0.0</span><br>
18755
18756
18757
18758
18759
18760
18761
18762
18763
18764
18765      </td>
18766
18767
18768
18769
18770
18771
18772
18773
18774
18775
18776      <td style="vertical-align: top;">Gradient(s) of the initial
18777profile of the&nbsp; v-component of the geostrophic wind (in 1/100s).<br>
18778
18779
18780
18781
18782
18783
18784
18785
18786
18787
18788      <br>
18789
18790
18791
18792
18793
18794
18795
18796
18797
18798
18799The gradient holds starting from the height level defined by <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>
18800(precisely: for all uv levels k where zu(k)
18801&gt; <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
18802vg(k) is set: vg(k) = vg(k-1) + dzu(k)
18803* <span style="font-weight: bold;">vg_vertical_gradient</span>) up to
18804the top boundary or up to the next height
18805level defined by <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>.
18806A total of 10 different
18807gradients for 11 height intervals (10 intervals&nbsp; if <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>(1) =
188080.0) can be assigned. The surface
18809geostrophic wind is assigned by <a href="#vg_surface">vg_surface</a>.</td>
18810
18811
18812
18813
18814
18815
18816
18817
18818
18819
18820    </tr>
18821
18822
18823
18824
18825
18826
18827
18828
18829
18830
18831    <tr>
18832
18833
18834
18835
18836
18837
18838
18839
18840
18841
18842      <td style="vertical-align: top;">
18843     
18844     
18845     
18846     
18847     
18848     
18849     
18850     
18851     
18852     
18853      <p><a name="vg_vertical_gradient_level"></a><span style="font-weight: bold;">vg_vertical_gradient_level</span></p>
18854
18855
18856
18857
18858
18859
18860
18861
18862
18863
18864      </td>
18865
18866
18867
18868
18869
18870
18871
18872
18873
18874
18875      <td style="vertical-align: top;">R(10)<br>
18876
18877
18878
18879
18880
18881
18882
18883
18884
18885
18886      </td>
18887
18888
18889
18890
18891
18892
18893
18894
18895
18896
18897      <td style="vertical-align: top;"><span style="font-style: italic;">10
18898* 0.0</span><br>
18899
18900
18901
18902
18903
18904
18905
18906
18907
18908
18909      </td>
18910
18911
18912
18913
18914
18915
18916
18917
18918
18919
18920      <td style="vertical-align: top;">Height level from which on the
18921gradient defined by <a href="#vg_vertical_gradient">vg_vertical_gradient</a>
18922is effective (in m).<br>
18923
18924
18925
18926
18927
18928
18929
18930
18931
18932
18933      <br>
18934
18935
18936
18937
18938
18939
18940
18941
18942
18943
18944The height levels are to be assigned in ascending order. For the
18945piecewise construction of a profile of the v-component of the
18946geostrophic wind component (vg) see <a href="#vg_vertical_gradient">vg_vertical_gradient</a>.</td>
18947
18948
18949
18950
18951
18952
18953
18954
18955
18956
18957    </tr>
18958
18959
18960
18961
18962
18963
18964
18965
18966
18967
18968    <tr>
18969
18970
18971
18972
18973
18974
18975
18976
18977
18978
18979      <td style="vertical-align: top;">
18980     
18981     
18982     
18983     
18984     
18985     
18986     
18987     
18988     
18989     
18990      <p><a name="wall_adjustment"></a><b>wall_adjustment</b></p>
18991
18992
18993
18994
18995
18996
18997
18998
18999
19000
19001      </td>
19002
19003
19004
19005
19006
19007
19008
19009
19010
19011
19012      <td style="vertical-align: top;">L</td>
19013
19014
19015
19016
19017
19018
19019
19020
19021
19022
19023      <td style="vertical-align: top;"><i>.T.</i></td>
19024
19025
19026
19027
19028
19029
19030
19031
19032
19033
19034      <td style="vertical-align: top;">
19035     
19036     
19037     
19038     
19039     
19040     
19041     
19042     
19043     
19044     
19045      <p>Parameter to restrict the mixing length in the vicinity of the
19046bottom
19047boundary.&nbsp; </p>
19048
19049
19050
19051
19052
19053
19054
19055
19056
19057
19058     
19059     
19060     
19061     
19062     
19063     
19064     
19065     
19066     
19067     
19068      <p>With <b>wall_adjustment</b> = <i>.TRUE., </i>the mixing
19069length is limited to a maximum of&nbsp; 1.8 * z. This condition
19070typically affects only the
19071first grid points above the bottom boundary.</p>
19072
19073
19074
19075
19076
19077
19078
19079
19080
19081
19082      </td>
19083
19084
19085
19086
19087
19088
19089
19090
19091
19092
19093    </tr>
19094
19095
19096
19097
19098
19099
19100    <tr>
19101
19102
19103
19104
19105
19106
19107      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="wall_heatflux"></a>wall_heatflux</span></td>
19108
19109
19110
19111
19112
19113
19114      <td style="vertical-align: top;">R(5)</td>
19115
19116
19117
19118
19119
19120
19121      <td style="vertical-align: top;"><span style="font-style: italic;">5 * 0.0</span></td>
19122
19123
19124
19125
19126
19127
19128      <td>Prescribed kinematic sensible heat flux in W m<sup>-2</sup>
19129at the five topography faces:<br>
19130
19131
19132
19133      <br>
19134
19135
19136
19137     
19138     
19139     
19140      <div style="margin-left: 40px;"><span style="font-weight: bold;">wall_heatflux(0)&nbsp;&nbsp; &nbsp;</span>top face<br>
19141
19142
19143
19144      <span style="font-weight: bold;">wall_heatflux(1)&nbsp;&nbsp;&nbsp; </span>left face<br>
19145
19146
19147
19148      <span style="font-weight: bold;">wall_heatflux(2)&nbsp;&nbsp;&nbsp; </span>right face<br>
19149
19150
19151
19152      <span style="font-weight: bold;">wall_heatflux(3)&nbsp;&nbsp;&nbsp; </span>south face<br>
19153
19154
19155
19156      <span style="font-weight: bold;">wall_heatflux(4)&nbsp;&nbsp;&nbsp; </span>north face</div>
19157
19158
19159
19160      <br>
19161
19162
19163
19164This parameter applies only in case of a non-flat <a href="#topography">topography</a>.&nbsp;The parameter <a href="#random_heatflux">random_heatflux</a>
19165can be used to impose random perturbations on the internal two-dimensional surface heat
19166flux field <span style="font-style: italic;">shf</span> that is composed of <a href="#surface_heatflux">surface_heatflux</a> at the bottom surface and <span style="font-weight: bold;">wall_heatflux(0)</span> at the topography top face.&nbsp;</td>
19167
19168
19169
19170
19171
19172
19173    </tr>
19174
19175
19176
19177
19178
19179
19180
19181
19182
19183
19184 
19185 
19186 
19187 
19188 
19189 
19190 
19191 
19192 
19193 
19194  </tbody>
19195</table>
19196
19197
19198
19199
19200
19201
19202
19203
19204
19205
19206<br>
19207
19208
19209
19210
19211
19212
19213
19214
19215
19216
19217<p style="line-height: 100%;"><br>
19218
19219
19220
19221
19222
19223
19224
19225
19226
19227
19228<font color="#000080"><font color="#000080"><a href="chapter_4.0.html"><font color="#000080"><img name="Grafik1" src="left.gif" align="bottom" border="2" height="32" width="32"></font></a><a href="index.html"><font color="#000080"><img name="Grafik2" src="up.gif" align="bottom" border="2" height="32" width="32"></font></a><a href="chapter_4.2.html"><font color="#000080"><img name="Grafik3" src="right.gif" align="bottom" border="2" height="32" width="32"></font></a></font></font></p>
19229
19230
19231
19232
19233
19234
19235
19236
19237
19238
19239<p style="line-height: 100%;"><i>Last change:&nbsp;</i> 22/08/06 (SR) </p>
19240
19241
19242
19243
19244
19245
19246
19247
19248
19249
19250<br>
19251
19252
19253
19254
19255
19256
19257
19258
19259
19260
19261<br>
19262
19263
19264
19265
19266
19267
19268
19269
19270
19271
19272</body></html>
Note: See TracBrowser for help on using the repository browser.