source: palm/trunk/DOC/app/chapter_4.1.html @ 165

Last change on this file since 165 was 165, checked in by letzel, 17 years ago
  • added reference to wall_heatflux in description of topography_mode in chapter 4.1
  • Property svn:keywords set to Id
File size: 206.0 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  <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
17
18
19
20
21
22
23 
24 
25 
26 
27 
28 
29  <title>PALM chapter 4.1</title></head>
30<body>
31
32
33
34
35
36
37<h3><a name="chapter4.1"></a>4.1
38Initialization parameters</h3>
39
40
41
42
43
44
45
46<br>
47
48
49
50
51
52
53<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
54
55
56
57
58
59
60 <tbody>
61
62
63
64
65
66
67
68    <tr>
69
70
71
72
73
74
75 <td style="vertical-align: top;"><font size="4"><b>Parameter name</b></font></td>
76
77
78
79
80
81
82
83      <td style="vertical-align: top;"><font size="4"><b>Type</b></font></td>
84
85
86
87
88
89
90
91      <td style="vertical-align: top;"> 
92     
93     
94     
95     
96     
97     
98      <p><b><font size="4">Default</font></b> <br>
99
100
101
102
103
104
105 <b><font size="4">value</font></b></p>
106
107
108
109
110
111
112 </td>
113
114
115
116
117
118
119
120      <td style="vertical-align: top;"><font size="4"><b>Explanation</b></font></td>
121
122
123
124
125
126
127
128    </tr>
129
130
131
132
133
134
135 <tr>
136
137
138
139
140
141
142 <td style="vertical-align: top;">
143     
144     
145     
146     
147     
148     
149      <p><a name="adjust_mixing_length"></a><b>adjust_mixing_length</b></p>
150
151
152
153
154
155
156
157      </td>
158
159
160
161
162
163
164 <td style="vertical-align: top;">L</td>
165
166
167
168
169
170
171
172      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
173
174
175
176
177
178
179 <td style="vertical-align: top;"> 
180     
181     
182     
183     
184     
185     
186      <p style="font-style: normal;">Near-surface adjustment of the
187mixing length to the Prandtl-layer law.&nbsp; </p>
188
189
190
191
192
193
194 
195     
196     
197     
198     
199     
200     
201      <p>Usually
202the mixing length in LES models l<sub>LES</sub>
203depends (as in PALM) on the grid size and is possibly restricted
204further in case of stable stratification and near the lower wall (see
205parameter <a href="#wall_adjustment">wall_adjustment</a>).
206With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span>
207the Prandtl' mixing length l<sub>PR</sub> = kappa * z/phi
208is calculated
209and the mixing length actually used in the model is set l = MIN (l<sub>LES</sub>,
210l<sub>PR</sub>). This usually gives a decrease of the
211mixing length at
212the bottom boundary and considers the fact that eddy sizes
213decrease in the vicinity of the wall.&nbsp; </p>
214
215
216
217
218
219
220 
221     
222     
223     
224     
225     
226     
227      <p style="font-style: normal;"><b>Warning:</b> So
228far, there is
229no good experience with <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> !&nbsp; </p>
230
231
232
233
234
235
236
237     
238     
239     
240     
241     
242     
243      <p>With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> and the
244Prandtl-layer being
245switched on (see <a href="#prandtl_layer">prandtl_layer</a>)
246      <span style="font-style: italic;">'(u*)** 2+neumann'</span>
247should always be set as the lower boundary condition for the TKE (see <a href="#bc_e_b">bc_e_b</a>),
248otherwise the near-surface value of the TKE is not in agreement with
249the Prandtl-layer law (Prandtl-layer law and Prandtl-Kolmogorov-Ansatz
250should provide the same value for K<sub>m</sub>). A warning
251is given,
252if this is not the case.</p>
253
254
255
256
257
258
259 </td>
260
261
262
263
264
265
266 </tr>
267
268
269
270
271
272
273 <tr>
274
275
276
277
278
279
280
281      <td style="vertical-align: top;"> 
282     
283     
284     
285     
286     
287     
288      <p><a name="alpha_surface"></a><b>alpha_surface</b></p>
289
290
291
292
293
294
295
296      </td>
297
298
299
300
301
302
303 <td style="vertical-align: top;">R<br>
304
305
306
307
308
309
310 </td>
311
312
313
314
315
316
317
318      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
319
320
321
322
323
324
325 </td>
326
327
328
329
330
331
332
333      <td style="vertical-align: top;"> 
334     
335     
336     
337     
338     
339     
340      <p style="font-style: normal;">Inclination of the model domain
341with respect to the horizontal (in degrees).&nbsp; </p>
342
343
344
345
346
347
348 
349     
350     
351     
352     
353     
354     
355      <p style="font-style: normal;">By means of <b>alpha_surface</b>
356the model domain can be inclined in x-direction with respect to the
357horizontal. In this way flows over inclined surfaces (e.g. drainage
358flows, gravity flows) can be simulated. In case of <b>alpha_surface
359      </b>/= <span style="font-style: italic;">0</span>
360the buoyancy term
361appears both in
362the equation of motion of the u-component and of the w-component.<br>
363
364
365
366
367
368
369
370      </p>
371
372
373
374
375
376
377 
378     
379     
380     
381     
382     
383     
384      <p style="font-style: normal;">An inclination
385is only possible in
386case of cyclic horizontal boundary conditions along x AND y (see <a href="#bc_lr">bc_lr</a>
387and <a href="#bc_ns">bc_ns</a>) and <a href="#topography">topography</a> = <span style="font-style: italic;">'flat'</span>. </p>
388
389
390
391
392
393
394
395     
396     
397     
398     
399     
400     
401      <p>Runs with inclined surface still require additional
402user-defined code as well as modifications to the default code. Please
403ask the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/PALM_group.html#0">PALM
404developer&nbsp; group</a>.</p>
405
406
407
408
409
410
411 </td>
412
413
414
415
416
417
418 </tr>
419
420
421
422
423
424
425
426    <tr>
427
428
429
430
431
432
433 <td style="vertical-align: top;"> 
434     
435     
436     
437     
438     
439     
440      <p><a name="bc_e_b"></a><b>bc_e_b</b></p>
441
442
443
444
445
446
447 </td>
448
449
450
451
452
453
454
455      <td style="vertical-align: top;">C * 20</td>
456
457
458
459
460
461
462 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
463
464
465
466
467
468
469
470      <td style="vertical-align: top;"> 
471     
472     
473     
474     
475     
476     
477      <p style="font-style: normal;">Bottom boundary condition of the
478TKE.&nbsp; </p>
479
480
481
482
483
484
485 
486     
487     
488     
489     
490     
491     
492      <p><b>bc_e_b</b> may be
493set to&nbsp;<span style="font-style: italic;">'neumann'</span>
494or <span style="font-style: italic;">'(u*) ** 2+neumann'</span>.
495      <b>bc_e_b</b>
496= <span style="font-style: italic;">'neumann'</span>
497yields to
498e(k=0)=e(k=1) (Neumann boundary condition), where e(k=1) is calculated
499via the prognostic TKE equation. Choice of <span style="font-style: italic;">'(u*)**2+neumann'</span>
500also yields to
501e(k=0)=e(k=1), but the TKE at the Prandtl-layer top (k=1) is calculated
502diagnostically by e(k=1)=(us/0.1)**2. However, this is only allowed if
503a Prandtl-layer is used (<a href="#prandtl_layer">prandtl_layer</a>).
504If this is not the case, a warning is given and <b>bc_e_b</b>
505is reset
506to <span style="font-style: italic;">'neumann'</span>.&nbsp;
507      </p>
508
509
510
511
512
513
514 
515     
516     
517     
518     
519     
520     
521      <p style="font-style: normal;">At the top
522boundary a Neumann
523boundary condition is generally used: (e(nz+1) = e(nz)).</p>
524
525
526
527
528
529
530 </td>
531
532
533
534
535
536
537
538    </tr>
539
540
541
542
543
544
545 <tr>
546
547
548
549
550
551
552 <td style="vertical-align: top;">
553     
554     
555     
556     
557     
558     
559      <p><a name="bc_lr"></a><b>bc_lr</b></p>
560
561
562
563
564
565
566
567      </td>
568
569
570
571
572
573
574 <td style="vertical-align: top;">C * 20</td>
575
576
577
578
579
580
581
582      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
583
584
585
586
587
588
589
590      <td style="vertical-align: top;">Boundary
591condition along x (for all quantities).<br>
592
593
594
595
596
597
598 <br>
599
600
601
602
603
604
605
606By default, a cyclic boundary condition is used along x.<br>
607
608
609
610
611
612
613 <br>
614
615
616
617
618
619
620
621      <span style="font-weight: bold;">bc_lr</span> may
622also be
623assigned the values <span style="font-style: italic;">'dirichlet/radiation'</span>
624(inflow from left, outflow to the right) or <span style="font-style: italic;">'radiation/dirichlet'</span>
625(inflow from
626right, outflow to the left). This requires the multi-grid method to be
627used 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>)
628and it also requires cyclic boundary conditions along y (see&nbsp;<a href="#bc_ns">bc_ns</a>).<br>
629
630
631
632
633
634
635 <br>
636
637
638
639
640
641
642
643In case of these non-cyclic lateral boundaries, a Dirichlet condition
644is used at the inflow for all quantities (initial vertical profiles -
645see <a href="#initializing_actions">initializing_actions</a>
646- are fixed during the run) except u, to which a Neumann (zero
647gradient) condition is applied. At the outflow, a radiation condition is used for all velocity components, while a Neumann (zero
648gradient) condition is used for the scalars. For perturbation
649pressure Neumann (zero gradient) conditions are assumed both at the
650inflow and at the outflow.<br>
651
652
653
654
655
656
657 <br>
658
659
660
661
662
663
664
665When using non-cyclic lateral boundaries, a filter is applied to the
666velocity field in the vicinity of the outflow in order to suppress any
667reflections of outgoing disturbances (see <a href="#km_damp_max">km_damp_max</a>
668and <a href="#outflow_damping_width">outflow_damping_width</a>).<br>
669
670
671
672
673
674
675
676      <br>
677
678
679
680
681
682
683
684In order to maintain a turbulent state of the flow, it may be
685neccessary to continuously impose perturbations on the horizontal
686velocity field in the vicinity of the inflow throughout the whole run.
687This 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>.
688The horizontal range to which these perturbations are applied is
689controlled by the parameters <a href="#inflow_disturbance_begin">inflow_disturbance_begin</a>
690and <a href="#inflow_disturbance_end">inflow_disturbance_end</a>.
691The 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>,
692      <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_level_t</a>,
693and <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_amplitude</a>.
694The 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>
695
696
697
698
699
700
701
702      <br>
703
704
705
706
707
708
709
710In 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
711at_all_substeps</a> = .T. should be used.<br>
712
713
714
715
716
717
718 <br>
719
720
721
722
723
724
725 <span style="font-weight: bold;">Note:</span><br>
726
727
728
729
730
731
732
733Using non-cyclic lateral boundaries requires very sensitive adjustments
734of the inflow (vertical profiles) and the bottom boundary conditions,
735e.g. a surface heating should not be applied near the inflow boundary
736because this may significantly disturb the inflow. Please check the
737model results very carefully.</td>
738
739
740
741
742
743
744 </tr>
745
746
747
748
749
750
751 <tr>
752
753
754
755
756
757
758 <td style="vertical-align: top;"> 
759     
760     
761     
762     
763     
764     
765      <p><a name="bc_ns"></a><b>bc_ns</b></p>
766
767
768
769
770
771
772
773      </td>
774
775
776
777
778
779
780 <td style="vertical-align: top;">C * 20</td>
781
782
783
784
785
786
787
788      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
789
790
791
792
793
794
795
796      <td style="vertical-align: top;">Boundary
797condition along y (for all quantities).<br>
798
799
800
801
802
803
804 <br>
805
806
807
808
809
810
811
812By default, a cyclic boundary condition is used along y.<br>
813
814
815
816
817
818
819 <br>
820
821
822
823
824
825
826
827      <span style="font-weight: bold;">bc_ns</span> may
828also be
829assigned the values <span style="font-style: italic;">'dirichlet/radiation'</span>
830(inflow from rear ("north"), outflow to the front ("south")) or <span style="font-style: italic;">'radiation/dirichlet'</span>
831(inflow from front ("south"), outflow to the rear ("north")). This
832requires the multi-grid
833method to be used for solving the Poisson equation for perturbation
834pressure (see <a href="chapter_4.2.html#psolver">psolver</a>)
835and it also requires cyclic boundary conditions along x (see<br>
836
837
838
839
840
841
842 <a href="#bc_lr">bc_lr</a>).<br>
843
844
845
846
847
848
849 <br>
850
851
852
853
854
855
856
857In case of these non-cyclic lateral boundaries, a Dirichlet condition
858is used at the inflow for all quantities (initial vertical profiles -
859see <a href="chapter_4.1.html#initializing_actions">initializing_actions</a>
860- are fixed during the run) except u, to which a Neumann (zero
861gradient) condition is applied. At the outflow, a radiation condition is used for all velocity components, while a Neumann (zero
862gradient) condition is used for the scalars. For perturbation
863pressure Neumann (zero gradient) conditions are assumed both at the
864inflow and at the outflow.<br>
865
866
867
868
869
870
871 <br>
872
873
874
875
876
877
878
879For further details regarding non-cyclic lateral boundary conditions
880see <a href="#bc_lr">bc_lr</a>.</td>
881
882
883
884
885
886
887 </tr>
888
889
890
891
892
893
894
895    <tr>
896
897
898
899
900
901
902 <td style="vertical-align: top;"> 
903     
904     
905     
906     
907     
908     
909      <p><a name="bc_p_b"></a><b>bc_p_b</b></p>
910
911
912
913
914
915
916 </td>
917
918
919
920
921
922
923
924      <td style="vertical-align: top;">C * 20</td>
925
926
927
928
929
930
931 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
932
933
934
935
936
937
938
939      <td style="vertical-align: top;"> 
940     
941     
942     
943     
944     
945     
946      <p style="font-style: normal;">Bottom boundary condition of the
947perturbation pressure.&nbsp; </p>
948
949
950
951
952
953
954 
955     
956     
957     
958     
959     
960     
961      <p>Allowed values
962are <span style="font-style: italic;">'dirichlet'</span>,
963      <span style="font-style: italic;">'neumann'</span>
964and <span style="font-style: italic;">'neumann+inhomo'</span>.&nbsp;
965      <span style="font-style: italic;">'dirichlet'</span>
966sets
967p(k=0)=0.0,&nbsp; <span style="font-style: italic;">'neumann'</span>
968sets p(k=0)=p(k=1). <span style="font-style: italic;">'neumann+inhomo'</span>
969corresponds to an extended Neumann boundary condition where heat flux
970or temperature inhomogeneities near the
971surface (pt(k=1))&nbsp; are additionally regarded (see Shen and
972LeClerc
973(1995, Q.J.R. Meteorol. Soc.,
9741209)). This condition is only permitted with the Prandtl-layer
975switched on (<a href="#prandtl_layer">prandtl_layer</a>),
976otherwise the run is terminated.&nbsp; </p>
977
978
979
980
981
982
983 
984     
985     
986     
987     
988     
989     
990      <p>Since
991at the bottom boundary of the model the vertical
992velocity
993disappears (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>)
994dp/dz = 0 should
995be used, which leaves the vertical component w unchanged when the
996pressure solver is applied. Simultaneous use of the Neumann boundary
997conditions both at the bottom and at the top boundary (<a href="#bc_p_t">bc_p_t</a>)
998usually yields no consistent solution for the perturbation pressure and
999should be avoided.</p>
1000
1001
1002
1003
1004
1005
1006 </td>
1007
1008
1009
1010
1011
1012
1013 </tr>
1014
1015
1016
1017
1018
1019
1020 <tr>
1021
1022
1023
1024
1025
1026
1027 <td style="vertical-align: top;"> 
1028     
1029     
1030     
1031     
1032     
1033     
1034      <p><a name="bc_p_t"></a><b>bc_p_t</b></p>
1035
1036
1037
1038
1039
1040
1041
1042      </td>
1043
1044
1045
1046
1047
1048
1049 <td style="vertical-align: top;">C * 20</td>
1050
1051
1052
1053
1054
1055
1056
1057      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1058
1059
1060
1061
1062
1063
1064
1065      <td style="vertical-align: top;"> 
1066     
1067     
1068     
1069     
1070     
1071     
1072      <p style="font-style: normal;">Top boundary condition of the
1073perturbation pressure.&nbsp; </p>
1074
1075
1076
1077
1078
1079
1080 
1081     
1082     
1083     
1084     
1085     
1086     
1087      <p style="font-style: normal;">Allowed values are <span style="font-style: italic;">'dirichlet'</span>
1088(p(k=nz+1)= 0.0) or <span style="font-style: italic;">'neumann'</span>
1089(p(k=nz+1)=p(k=nz)).&nbsp; </p>
1090
1091
1092
1093
1094
1095
1096 
1097     
1098     
1099     
1100     
1101     
1102     
1103      <p>Simultaneous use
1104of Neumann boundary conditions both at the
1105top and bottom boundary (<a href="#bc_p_b">bc_p_b</a>)
1106usually yields no consistent solution for the perturbation pressure and
1107should be avoided. Since at the bottom boundary the Neumann
1108condition&nbsp; is a good choice (see <a href="#bc_p_b">bc_p_b</a>),
1109a Dirichlet condition should be set at the top boundary.</p>
1110
1111
1112
1113
1114
1115
1116 </td>
1117
1118
1119
1120
1121
1122
1123
1124    </tr>
1125
1126
1127
1128
1129
1130
1131 <tr>
1132
1133
1134
1135
1136
1137
1138 <td style="vertical-align: top;">
1139     
1140     
1141     
1142     
1143     
1144     
1145      <p><a name="bc_pt_b"></a><b>bc_pt_b</b></p>
1146
1147
1148
1149
1150
1151
1152
1153      </td>
1154
1155
1156
1157
1158
1159
1160 <td style="vertical-align: top;">C*20</td>
1161
1162
1163
1164
1165
1166
1167
1168      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1169
1170
1171
1172
1173
1174
1175
1176      <td style="vertical-align: top;"> 
1177     
1178     
1179     
1180     
1181     
1182     
1183      <p style="font-style: normal;">Bottom boundary condition of the
1184potential temperature.&nbsp; </p>
1185
1186
1187
1188
1189
1190
1191 
1192     
1193     
1194     
1195     
1196     
1197     
1198      <p>Allowed values
1199are <span style="font-style: italic;">'dirichlet'</span>
1200(pt(k=0) = const. = <a href="#pt_surface">pt_surface</a>
1201+ <a href="#pt_surface_initial_change">pt_surface_initial_change</a>;
1202the user may change this value during the run using user-defined code)
1203and <span style="font-style: italic;">'neumann'</span>
1204(pt(k=0)=pt(k=1)).&nbsp; <br>
1205
1206
1207
1208
1209
1210
1211
1212When a constant surface sensible heat flux is used (<a href="#surface_heatflux">surface_heatflux</a>), <b>bc_pt_b</b>
1213= <span style="font-style: italic;">'neumann'</span>
1214must be used, because otherwise the resolved scale may contribute to
1215the surface flux so that a constant value cannot be guaranteed.</p>
1216
1217
1218
1219
1220
1221
1222     
1223     
1224     
1225     
1226     
1227     
1228      <p>In the <a href="chapter_3.8.html">coupled</a> atmosphere executable,&nbsp;<a href="chapter_4.2.html#bc_pt_b">bc_pt_b</a> is internally set and does not need to be prescribed.</p>
1229
1230
1231
1232
1233
1234
1235
1236      </td>
1237
1238
1239
1240
1241
1242
1243 </tr>
1244
1245
1246
1247
1248
1249
1250 <tr>
1251
1252
1253
1254
1255
1256
1257 <td style="vertical-align: top;"> 
1258     
1259     
1260     
1261     
1262     
1263     
1264      <p><a name="pc_pt_t"></a><b>bc_pt_t</b></p>
1265
1266
1267
1268
1269
1270
1271
1272      </td>
1273
1274
1275
1276
1277
1278
1279 <td style="vertical-align: top;">C * 20</td>
1280
1281
1282
1283
1284
1285
1286
1287      <td style="vertical-align: top;"><span style="font-style: italic;">'initial_ gradient'</span></td>
1288
1289
1290
1291
1292
1293
1294
1295      <td style="vertical-align: top;"> 
1296     
1297     
1298     
1299     
1300     
1301     
1302      <p style="font-style: normal;">Top boundary condition of the
1303potential temperature.&nbsp; </p>
1304
1305
1306
1307
1308
1309
1310 
1311     
1312     
1313     
1314     
1315     
1316     
1317      <p>Allowed are the
1318values <span style="font-style: italic;">'dirichlet' </span>(pt(k=nz+1)
1319does not change during the run), <span style="font-style: italic;">'neumann'</span>
1320(pt(k=nz+1)=pt(k=nz)), and <span style="font-style: italic;">'initial_gradient'</span>.
1321With the 'initial_gradient'-condition the value of the temperature
1322gradient at the top is
1323calculated from the initial
1324temperature profile (see <a href="#pt_surface">pt_surface</a>,
1325      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>)
1326by bc_pt_t_val = (pt_init(k=nz+1) -
1327pt_init(k=nz)) / dzu(nz+1).<br>
1328
1329
1330
1331
1332
1333
1334
1335Using this value (assumed constant during the
1336run) the temperature boundary values are calculated as&nbsp; </p>
1337
1338
1339
1340
1341
1342
1343
1344     
1345     
1346     
1347     
1348     
1349     
1350      <ul>
1351
1352
1353
1354
1355
1356
1357 
1358       
1359       
1360       
1361       
1362       
1363       
1364        <p style="font-style: normal;">pt(k=nz+1) =
1365pt(k=nz) +
1366bc_pt_t_val * dzu(nz+1)</p>
1367
1368
1369
1370
1371
1372
1373 
1374     
1375     
1376     
1377     
1378     
1379     
1380      </ul>
1381
1382
1383
1384
1385
1386
1387 
1388     
1389     
1390     
1391     
1392     
1393     
1394      <p style="font-style: normal;">(up to k=nz the prognostic
1395equation for the temperature is solved).<br>
1396
1397
1398
1399
1400
1401
1402
1403When a constant sensible heat flux is used at the top boundary (<a href="chapter_4.1.html#top_heatflux">top_heatflux</a>),
1404      <b>bc_pt_t</b> = <span style="font-style: italic;">'neumann'</span>
1405must be used, because otherwise the resolved scale may contribute to
1406the top flux so that a constant value cannot be guaranteed.</p>
1407
1408
1409
1410
1411
1412
1413 </td>
1414
1415
1416
1417
1418
1419
1420
1421    </tr>
1422
1423
1424
1425
1426
1427
1428 <tr>
1429
1430
1431
1432
1433
1434
1435 <td style="vertical-align: top;">
1436     
1437     
1438     
1439     
1440     
1441     
1442      <p><a name="bc_q_b"></a><b>bc_q_b</b></p>
1443
1444
1445
1446
1447
1448
1449
1450      </td>
1451
1452
1453
1454
1455
1456
1457 <td style="vertical-align: top;">C * 20</td>
1458
1459
1460
1461
1462
1463
1464
1465      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1466
1467
1468
1469
1470
1471
1472
1473      <td style="vertical-align: top;"> 
1474     
1475     
1476     
1477     
1478     
1479     
1480      <p style="font-style: normal;">Bottom boundary condition of the
1481specific humidity / total water content.&nbsp; </p>
1482
1483
1484
1485
1486
1487
1488 
1489     
1490     
1491     
1492     
1493     
1494     
1495      <p>Allowed
1496values are <span style="font-style: italic;">'dirichlet'</span>
1497(q(k=0) = const. = <a href="#q_surface">q_surface</a>
1498+ <a href="#q_surface_initial_change">q_surface_initial_change</a>;
1499the user may change this value during the run using user-defined code)
1500and <span style="font-style: italic;">'neumann'</span>
1501(q(k=0)=q(k=1)).&nbsp; <br>
1502
1503
1504
1505
1506
1507
1508
1509When a constant surface latent heat flux is used (<a href="#surface_waterflux">surface_waterflux</a>), <b>bc_q_b</b>
1510= <span style="font-style: italic;">'neumann'</span>
1511must be used, because otherwise the resolved scale may contribute to
1512the surface flux so that a constant value cannot be guaranteed.</p>
1513
1514
1515
1516
1517
1518
1519
1520      </td>
1521
1522
1523
1524
1525
1526
1527 </tr>
1528
1529
1530
1531
1532
1533
1534 <tr>
1535
1536
1537
1538
1539
1540
1541 <td style="vertical-align: top;"> 
1542     
1543     
1544     
1545     
1546     
1547     
1548      <p><a name="bc_q_t"></a><b>bc_q_t</b></p>
1549
1550
1551
1552
1553
1554
1555
1556      </td>
1557
1558
1559
1560
1561
1562
1563 <td style="vertical-align: top;"><span style="font-style: italic;">C
1564* 20</span></td>
1565
1566
1567
1568
1569
1570
1571 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1572
1573
1574
1575
1576
1577
1578
1579      <td style="vertical-align: top;"> 
1580     
1581     
1582     
1583     
1584     
1585     
1586      <p style="font-style: normal;">Top boundary condition of the
1587specific humidity / total water content.&nbsp; </p>
1588
1589
1590
1591
1592
1593
1594 
1595     
1596     
1597     
1598     
1599     
1600     
1601      <p>Allowed
1602are the values <span style="font-style: italic;">'dirichlet'</span>
1603(q(k=nz) and q(k=nz+1) do
1604not change during the run) and <span style="font-style: italic;">'neumann'</span>.
1605With the Neumann boundary
1606condition the value of the humidity gradient at the top is calculated
1607from the
1608initial humidity profile (see <a href="#q_surface">q_surface</a>,
1609      <a href="#q_vertical_gradient">q_vertical_gradient</a>)
1610by: bc_q_t_val = ( q_init(k=nz) - q_init(k=nz-1)) / dzu(nz).<br>
1611
1612
1613
1614
1615
1616
1617
1618Using this value (assumed constant during the run) the humidity
1619boundary values
1620are calculated as&nbsp; </p>
1621
1622
1623
1624
1625
1626
1627 
1628     
1629     
1630     
1631     
1632     
1633     
1634      <ul>
1635
1636
1637
1638
1639
1640
1641 
1642       
1643       
1644       
1645       
1646       
1647       
1648        <p style="font-style: normal;">q(k=nz+1) =q(k=nz) +
1649bc_q_t_val * dzu(nz+1)</p>
1650
1651
1652
1653
1654
1655
1656 
1657     
1658     
1659     
1660     
1661     
1662     
1663      </ul>
1664
1665
1666
1667
1668
1669
1670 
1671     
1672     
1673     
1674     
1675     
1676     
1677      <p style="font-style: normal;">(up tp k=nz the prognostic
1678equation for q is solved). </p>
1679
1680
1681
1682
1683
1684
1685 </td>
1686
1687
1688
1689
1690
1691
1692 </tr>
1693
1694
1695
1696
1697
1698
1699 <tr>
1700
1701
1702
1703
1704
1705
1706
1707      <td style="vertical-align: top;"> 
1708     
1709     
1710     
1711     
1712     
1713     
1714      <p><a name="bc_s_b"></a><b>bc_s_b</b></p>
1715
1716
1717
1718
1719
1720
1721 </td>
1722
1723
1724
1725
1726
1727
1728
1729      <td style="vertical-align: top;">C * 20</td>
1730
1731
1732
1733
1734
1735
1736 <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1737
1738
1739
1740
1741
1742
1743
1744      <td style="vertical-align: top;"> 
1745     
1746     
1747     
1748     
1749     
1750     
1751      <p style="font-style: normal;">Bottom boundary condition of the
1752scalar concentration.&nbsp; </p>
1753
1754
1755
1756
1757
1758
1759 
1760     
1761     
1762     
1763     
1764     
1765     
1766      <p>Allowed values
1767are <span style="font-style: italic;">'dirichlet'</span>
1768(s(k=0) = const. = <a href="#s_surface">s_surface</a>
1769+ <a href="#s_surface_initial_change">s_surface_initial_change</a>;
1770the user may change this value during the run using user-defined code)
1771and <span style="font-style: italic;">'neumann'</span>
1772(s(k=0) =
1773s(k=1)).&nbsp; <br>
1774
1775
1776
1777
1778
1779
1780
1781When a constant surface concentration flux is used (<a href="#surface_scalarflux">surface_scalarflux</a>), <b>bc_s_b</b>
1782= <span style="font-style: italic;">'neumann'</span>
1783must be used, because otherwise the resolved scale may contribute to
1784the surface flux so that a constant value cannot be guaranteed.</p>
1785
1786
1787
1788
1789
1790
1791
1792      </td>
1793
1794
1795
1796
1797
1798
1799 </tr>
1800
1801
1802
1803
1804
1805
1806 <tr>
1807
1808
1809
1810
1811
1812
1813 <td style="vertical-align: top;"> 
1814     
1815     
1816     
1817     
1818     
1819     
1820      <p><a name="bc_s_t"></a><b>bc_s_t</b></p>
1821
1822
1823
1824
1825
1826
1827
1828      </td>
1829
1830
1831
1832
1833
1834
1835 <td style="vertical-align: top;">C * 20</td>
1836
1837
1838
1839
1840
1841
1842
1843      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1844
1845
1846
1847
1848
1849
1850
1851      <td style="vertical-align: top;"> 
1852     
1853     
1854     
1855     
1856     
1857     
1858      <p style="font-style: normal;">Top boundary condition of the
1859scalar concentration.&nbsp; </p>
1860
1861
1862
1863
1864
1865
1866 
1867     
1868     
1869     
1870     
1871     
1872     
1873      <p>Allowed are the
1874values <span style="font-style: italic;">'dirichlet'</span>
1875(s(k=nz) and s(k=nz+1) do
1876not change during the run) and <span style="font-style: italic;">'neumann'</span>.
1877With the Neumann boundary
1878condition the value of the scalar concentration gradient at the top is
1879calculated
1880from the initial scalar concentration profile (see <a href="#s_surface">s_surface</a>, <a href="#s_vertical_gradient">s_vertical_gradient</a>)
1881by: bc_s_t_val = (s_init(k=nz) - s_init(k=nz-1)) / dzu(nz).<br>
1882
1883
1884
1885
1886
1887
1888
1889Using this value (assumed constant during the run) the concentration
1890boundary values
1891are calculated as </p>
1892
1893
1894
1895
1896
1897
1898 
1899     
1900     
1901     
1902     
1903     
1904     
1905      <ul>
1906
1907
1908
1909
1910
1911
1912 
1913       
1914       
1915       
1916       
1917       
1918       
1919        <p style="font-style: normal;">s(k=nz+1) = s(k=nz) +
1920bc_s_t_val * dzu(nz+1)</p>
1921
1922
1923
1924
1925
1926
1927 
1928     
1929     
1930     
1931     
1932     
1933     
1934      </ul>
1935
1936
1937
1938
1939
1940
1941 
1942     
1943     
1944     
1945     
1946     
1947     
1948      <p style="font-style: normal;">(up to k=nz the prognostic
1949equation for the scalar concentration is
1950solved).</p>
1951
1952
1953
1954
1955
1956
1957 </td>
1958
1959
1960
1961
1962
1963
1964 </tr>
1965
1966
1967
1968
1969
1970
1971 <tr>
1972
1973
1974
1975
1976
1977
1978      <td style="vertical-align: top;"><a name="bc_sa_t"></a><span style="font-weight: bold;">bc_sa_t</span></td>
1979
1980
1981
1982
1983
1984
1985      <td style="vertical-align: top;">C * 20</td>
1986
1987
1988
1989
1990
1991
1992      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1993
1994
1995
1996
1997
1998
1999      <td style="vertical-align: top;">
2000     
2001     
2002     
2003     
2004     
2005     
2006      <p style="font-style: normal;">Top boundary condition of the salinity.&nbsp; </p>
2007
2008
2009
2010
2011
2012
2013 
2014     
2015     
2016     
2017     
2018     
2019     
2020      <p>This parameter only comes into effect for ocean runs (see parameter <a href="#ocean">ocean</a>).</p>
2021
2022
2023
2024
2025
2026
2027     
2028     
2029     
2030     
2031     
2032     
2033      <p style="font-style: normal;">Allowed are the
2034values <span style="font-style: italic;">'dirichlet' </span>(sa(k=nz+1)
2035does not change during the run) and <span style="font-style: italic;">'neumann'</span>
2036(sa(k=nz+1)=sa(k=nz))<span style="font-style: italic;"></span>.&nbsp;<br>
2037
2038
2039
2040
2041
2042
2043      <br>
2044
2045
2046
2047
2048
2049
2050
2051When a constant salinity flux is used at the top boundary (<a href="chapter_4.1.html#top_salinityflux">top_salinityflux</a>),
2052      <b>bc_sa_t</b> = <span style="font-style: italic;">'neumann'</span>
2053must be used, because otherwise the resolved scale may contribute to
2054the top flux so that a constant value cannot be guaranteed.</p>
2055
2056
2057
2058
2059
2060
2061      </td>
2062
2063
2064
2065
2066
2067
2068    </tr>
2069
2070
2071
2072
2073
2074
2075    <tr>
2076
2077
2078
2079
2080
2081
2082 <td style="vertical-align: top;"> 
2083     
2084     
2085     
2086     
2087     
2088     
2089      <p><a name="bc_uv_b"></a><b>bc_uv_b</b></p>
2090
2091
2092
2093
2094
2095
2096
2097      </td>
2098
2099
2100
2101
2102
2103
2104 <td style="vertical-align: top;">C * 20</td>
2105
2106
2107
2108
2109
2110
2111
2112      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2113
2114
2115
2116
2117
2118
2119
2120      <td style="vertical-align: top;"> 
2121     
2122     
2123     
2124     
2125     
2126     
2127      <p style="font-style: normal;">Bottom boundary condition of the
2128horizontal velocity components u and v.&nbsp; </p>
2129
2130
2131
2132
2133
2134
2135 
2136     
2137     
2138     
2139     
2140     
2141     
2142      <p>Allowed
2143values are <span style="font-style: italic;">'dirichlet' </span>and
2144      <span style="font-style: italic;">'neumann'</span>. <b>bc_uv_b</b>
2145= <span style="font-style: italic;">'dirichlet'</span>
2146yields the
2147no-slip condition with u=v=0 at the bottom. Due to the staggered grid
2148u(k=0) and v(k=0) are located at z = - 0,5 * <a href="#dz">dz</a>
2149(below the bottom), while u(k=1) and v(k=1) are located at z = +0,5 *
2150dz. u=v=0 at the bottom is guaranteed using mirror boundary
2151condition:&nbsp; </p>
2152
2153
2154
2155
2156
2157
2158 
2159     
2160     
2161     
2162     
2163     
2164     
2165      <ul>
2166
2167
2168
2169
2170
2171
2172 
2173       
2174       
2175       
2176       
2177       
2178       
2179        <p style="font-style: normal;">u(k=0) = - u(k=1) and v(k=0) = -
2180v(k=1)</p>
2181
2182
2183
2184
2185
2186
2187 
2188     
2189     
2190     
2191     
2192     
2193     
2194      </ul>
2195
2196
2197
2198
2199
2200
2201 
2202     
2203     
2204     
2205     
2206     
2207     
2208      <p style="font-style: normal;">The
2209Neumann boundary condition
2210yields the free-slip condition with u(k=0) = u(k=1) and v(k=0) =
2211v(k=1).
2212With Prandtl - layer switched on, the free-slip condition is not
2213allowed (otherwise the run will be terminated)<font color="#000000">.</font></p>
2214
2215
2216
2217
2218
2219
2220
2221      </td>
2222
2223
2224
2225
2226
2227
2228 </tr>
2229
2230
2231
2232
2233
2234
2235 <tr>
2236
2237
2238
2239
2240
2241
2242 <td style="vertical-align: top;"> 
2243     
2244     
2245     
2246     
2247     
2248     
2249      <p><a name="bc_uv_t"></a><b>bc_uv_t</b></p>
2250
2251
2252
2253
2254
2255
2256
2257      </td>
2258
2259
2260
2261
2262
2263
2264 <td style="vertical-align: top;">C * 20</td>
2265
2266
2267
2268
2269
2270
2271
2272      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2273
2274
2275
2276
2277
2278
2279
2280      <td style="vertical-align: top;"> 
2281     
2282     
2283     
2284     
2285     
2286     
2287      <p style="font-style: normal;">Top boundary condition of the
2288horizontal velocity components u and v.&nbsp; </p>
2289
2290
2291
2292
2293
2294
2295 
2296     
2297     
2298     
2299     
2300     
2301     
2302      <p>Allowed
2303values are <span style="font-style: italic;">'dirichlet'</span>, <span style="font-style: italic;">'dirichlet_0'</span>
2304and <span style="font-style: italic;">'neumann'</span>.
2305The
2306Dirichlet condition yields u(k=nz+1) = ug(nz+1) and v(k=nz+1) =
2307vg(nz+1),
2308Neumann condition yields the free-slip condition with u(k=nz+1) =
2309u(k=nz) and v(k=nz+1) = v(k=nz) (up to k=nz the prognostic equations
2310for the velocities are solved). The special condition&nbsp;<span style="font-style: italic;">'dirichlet_0'</span> can be used for channel flow, it yields the no-slip condition u(k=nz+1) = ug(nz+1) = 0 and v(k=nz+1) =
2311vg(nz+1) = 0.</p>
2312
2313
2314
2315
2316
2317
2318     
2319     
2320     
2321     
2322     
2323     
2324      <p>In the <a href="chapter_3.8.html">coupled</a> ocean executable, <a href="chapter_4.2.html#bc_uv_t">bc_uv_t</a>&nbsp;is internally set ('neumann') and does not need to be prescribed.</p>
2325
2326
2327
2328
2329
2330
2331 </td>
2332
2333
2334
2335
2336
2337
2338 </tr>
2339
2340
2341
2342
2343
2344
2345 <tr>
2346
2347
2348
2349
2350
2351
2352      <td style="vertical-align: top;"><a name="bottom_salinityflux"></a><span style="font-weight: bold;">bottom_salinityflux</span></td>
2353
2354
2355
2356
2357
2358
2359      <td style="vertical-align: top;">R</td>
2360
2361
2362
2363
2364
2365
2366      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
2367
2368
2369
2370
2371
2372
2373      <td style="vertical-align: top;">
2374     
2375     
2376     
2377     
2378     
2379     
2380      <p>Kinematic salinity flux near the surface (in psu m/s).&nbsp;</p>
2381
2382
2383
2384
2385
2386
2387This parameter only comes into effect for ocean runs (see parameter <a href="chapter_4.1.html#ocean">ocean</a>).
2388     
2389     
2390     
2391     
2392     
2393     
2394      <p>The
2395respective salinity flux value is used
2396as bottom (horizontally homogeneous) boundary condition for the salinity equation. This additionally requires that a Neumann
2397condition must be used for the salinity, which is currently the only available condition.<br>
2398
2399
2400
2401
2402
2403
2404 </p>
2405
2406
2407
2408
2409
2410
2411 </td>
2412
2413
2414
2415
2416
2417
2418    </tr>
2419
2420
2421
2422
2423
2424
2425    <tr>
2426
2427
2428
2429
2430
2431
2432
2433      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_height"></a>building_height</span></td>
2434
2435
2436
2437
2438
2439
2440
2441      <td style="vertical-align: top;">R</td>
2442
2443
2444
2445
2446
2447
2448 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2449
2450
2451
2452
2453
2454
2455 <td>Height
2456of a single building in m.<br>
2457
2458
2459
2460
2461
2462
2463 <br>
2464
2465
2466
2467
2468
2469
2470 <span style="font-weight: bold;">building_height</span> must
2471be less than the height of the model domain. This parameter requires
2472the use of&nbsp;<a href="#topography">topography</a>
2473= <span style="font-style: italic;">'single_building'</span>.</td>
2474
2475
2476
2477
2478
2479
2480
2481    </tr>
2482
2483
2484
2485
2486
2487
2488 <tr>
2489
2490
2491
2492
2493
2494
2495 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_x"></a>building_length_x</span></td>
2496
2497
2498
2499
2500
2501
2502
2503      <td style="vertical-align: top;">R</td>
2504
2505
2506
2507
2508
2509
2510 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2511
2512
2513
2514
2515
2516
2517 <td><span style="font-style: italic;"></span>Width of a single
2518building in m.<br>
2519
2520
2521
2522
2523
2524
2525 <br>
2526
2527
2528
2529
2530
2531
2532
2533Currently, <span style="font-weight: bold;">building_length_x</span>
2534must be at least <span style="font-style: italic;">3
2535*&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>
2536      </span><span style="font-style: italic;">- <a href="#building_wall_left">building_wall_left</a></span>.
2537This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2538= <span style="font-style: italic;">'single_building'</span>.</td>
2539
2540
2541
2542
2543
2544
2545
2546    </tr>
2547
2548
2549
2550
2551
2552
2553 <tr>
2554
2555
2556
2557
2558
2559
2560 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_y"></a>building_length_y</span></td>
2561
2562
2563
2564
2565
2566
2567
2568      <td style="vertical-align: top;">R</td>
2569
2570
2571
2572
2573
2574
2575 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2576
2577
2578
2579
2580
2581
2582 <td>Depth
2583of a single building in m.<br>
2584
2585
2586
2587
2588
2589
2590 <br>
2591
2592
2593
2594
2595
2596
2597
2598Currently, <span style="font-weight: bold;">building_length_y</span>
2599must be at least <span style="font-style: italic;">3
2600*&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></span>. This parameter requires
2601the use of&nbsp;<a href="#topography">topography</a>
2602= <span style="font-style: italic;">'single_building'</span>.</td>
2603
2604
2605
2606
2607
2608
2609
2610    </tr>
2611
2612
2613
2614
2615
2616
2617 <tr>
2618
2619
2620
2621
2622
2623
2624 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_left"></a>building_wall_left</span></td>
2625
2626
2627
2628
2629
2630
2631
2632      <td style="vertical-align: top;">R</td>
2633
2634
2635
2636
2637
2638
2639 <td style="vertical-align: top;"><span style="font-style: italic;">building centered in x-direction</span></td>
2640
2641
2642
2643
2644
2645
2646
2647      <td>x-coordinate of the left building wall (distance between the
2648left building wall and the left border of the model domain) in m.<br>
2649
2650
2651
2652
2653
2654
2655
2656      <br>
2657
2658
2659
2660
2661
2662
2663
2664Currently, <span style="font-weight: bold;">building_wall_left</span>
2665must be at least <span style="font-style: italic;">1
2666*&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;
2667- 1 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a></span>.
2668This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2669= <span style="font-style: italic;">'single_building'</span>.<br>
2670
2671
2672
2673
2674
2675
2676
2677      <br>
2678
2679
2680
2681
2682
2683
2684
2685The default value&nbsp;<span style="font-weight: bold;">building_wall_left</span>
2686= <span style="font-style: italic;">( ( <a href="#nx">nx</a>&nbsp;+
26871 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a> ) / 2</span>
2688centers the building in x-direction.&nbsp;<font color="#000000">Due to the staggered grid the building will be displaced by -0.5 <a href="chapter_4.1.html#dx">dx</a> in x-direction and -0.5 <a href="chapter_4.1.html#dy">dy</a> in y-direction.</font> </td>
2689
2690
2691
2692
2693
2694
2695 </tr>
2696
2697
2698
2699
2700
2701
2702 <tr>
2703
2704
2705
2706
2707
2708
2709
2710      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_south"></a>building_wall_south</span></td>
2711
2712
2713
2714
2715
2716
2717
2718      <td style="vertical-align: top;">R</td>
2719
2720
2721
2722
2723
2724
2725 <td style="vertical-align: top;"><span style="font-style: italic;"></span><span style="font-style: italic;">building centered in y-direction</span></td>
2726
2727
2728
2729
2730
2731
2732
2733      <td>y-coordinate of the South building wall (distance between the
2734South building wall and the South border of the model domain) in m.<br>
2735
2736
2737
2738
2739
2740
2741
2742      <br>
2743
2744
2745
2746
2747
2748
2749
2750Currently, <span style="font-weight: bold;">building_wall_south</span>
2751must be at least <span style="font-style: italic;">1
2752*&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;
2753- 1 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a></span>.
2754This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2755= <span style="font-style: italic;">'single_building'</span>.<br>
2756
2757
2758
2759
2760
2761
2762
2763      <br>
2764
2765
2766
2767
2768
2769
2770
2771The default value&nbsp;<span style="font-weight: bold;">building_wall_south</span>
2772= <span style="font-style: italic;">( ( <a href="#ny">ny</a>&nbsp;+
27731 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a> ) / 2</span>
2774centers the building in y-direction.&nbsp;<font color="#000000">Due to the staggered grid the building will be displaced by -0.5 <a href="chapter_4.1.html#dx">dx</a> in x-direction and -0.5 <a href="chapter_4.1.html#dy">dy</a> in y-direction.</font> </td>
2775
2776
2777
2778
2779
2780
2781 </tr>
2782
2783
2784
2785
2786
2787
2788 <tr>
2789
2790      <td style="vertical-align: top;"><a name="canopy_mode"></a><span style="font-weight: bold;">canopy_mode</span></td>
2791
2792      <td style="vertical-align: top;">C * 20</td>
2793
2794      <td style="vertical-align: top;"><span style="font-style: italic;">'block'</span></td>
2795
2796      <td style="vertical-align: top;">Canopy mode.<br>
2797
2798      <br>
2799
2800      <font color="#000000">
2801Besides using the default value, that will create a horizontally
2802homogeneous plant canopy that extends over the total horizontal
2803extension of the model domain, the user may add code to the user
2804interface subroutine <a href="chapter_3.5.1.html#user_init_plant_canopy">user_init_plant_canopy</a>
2805to allow further canopy&nbsp;modes. <br>
2806
2807      <br>
2808
2809The setting of <a href="#canopy_mode">canopy_mode</a> becomes only active, if&nbsp;<a href="#plant_canopy">plant_canopy</a> has been set <span style="font-style: italic;">.T.</span> and a non-zero <a href="#drag_coefficient">drag_coefficient</a> has been defined.</font></td>
2810
2811    </tr>
2812
2813    <tr>
2814
2815
2816
2817
2818
2819
2820
2821      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="cloud_droplets"></a>cloud_droplets</span><br>
2822
2823
2824
2825
2826
2827
2828
2829      </td>
2830
2831
2832
2833
2834
2835
2836 <td style="vertical-align: top;">L<br>
2837
2838
2839
2840
2841
2842
2843 </td>
2844
2845
2846
2847
2848
2849
2850
2851      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span><br>
2852
2853
2854
2855
2856
2857
2858 </td>
2859
2860
2861
2862
2863
2864
2865
2866      <td style="vertical-align: top;">Parameter to switch on
2867usage of cloud droplets.<br>
2868
2869
2870
2871
2872
2873
2874 <br>
2875
2876
2877
2878
2879
2880
2881
2882      <span style="font-weight: bold;"></span><span style="font-family: monospace;"></span>
2883
2884
2885
2886
2887Cloud droplets require to use&nbsp;particles (i.e. the NAMELIST group <span style="font-family: Courier New,Courier,monospace;">particles_par</span> has to be included in the parameter file<span style="font-family: monospace;"></span>). Then each particle is a representative for a certain number of droplets. The droplet
2888features (number of droplets, initial radius, etc.) can be steered with
2889the&nbsp; respective particle parameters (see e.g. <a href="#chapter_4.2.html#radius">radius</a>).
2890The real number of initial droplets in a grid cell is equal to the
2891initial 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>
2892      <span lang="en-GB"><font face="Thorndale, serif">and
2893      </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>)
2894times the <a href="#initial_weighting_factor">initial_weighting_factor</a>.<br>
2895
2896
2897
2898
2899
2900
2901
2902      <br>
2903
2904
2905
2906
2907
2908
2909
2910In case of using cloud droplets, the default condensation scheme in
2911PALM cannot be used, i.e. <a href="#cloud_physics">cloud_physics</a>
2912must be set <span style="font-style: italic;">.F.</span>.<br>
2913
2914
2915
2916
2917
2918
2919
2920      </td>
2921
2922
2923
2924
2925
2926
2927 </tr>
2928
2929
2930
2931
2932
2933
2934 <tr>
2935
2936
2937
2938
2939
2940
2941 <td style="vertical-align: top;"> 
2942     
2943     
2944     
2945     
2946     
2947     
2948      <p><a name="cloud_physics"></a><b>cloud_physics</b></p>
2949
2950
2951
2952
2953
2954
2955
2956      </td>
2957
2958
2959
2960
2961
2962
2963 <td style="vertical-align: top;">L<br>
2964
2965
2966
2967
2968
2969
2970 </td>
2971
2972
2973
2974
2975
2976
2977
2978      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
2979
2980
2981
2982
2983
2984
2985 <td style="vertical-align: top;"> 
2986     
2987     
2988     
2989     
2990     
2991     
2992      <p>Parameter to switch
2993on the condensation scheme.&nbsp; </p>
2994
2995
2996
2997
2998
2999
3000
3001For <b>cloud_physics =</b> <span style="font-style: italic;">.TRUE.</span>, equations
3002for the
3003liquid water&nbsp;
3004content and the liquid water potential temperature are solved instead
3005of those for specific humidity and potential temperature. Note
3006that a grid volume is assumed to be either completely saturated or
3007completely
3008unsaturated (0%-or-100%-scheme). A simple precipitation scheme can
3009additionally be switched on with parameter <a href="#precipitation">precipitation</a>.
3010Also cloud-top cooling by longwave radiation can be utilized (see <a href="#radiation">radiation</a>)<br>
3011
3012
3013
3014
3015
3016
3017 <b><br>
3018
3019
3020
3021
3022
3023
3024
3025cloud_physics =</b> <span style="font-style: italic;">.TRUE.
3026      </span>requires&nbsp;<a href="#humidity">humidity</a>
3027=<span style="font-style: italic;"> .TRUE.</span> .<br>
3028
3029
3030
3031
3032
3033
3034
3035Detailed information about the condensation scheme is given in the
3036description of the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM-1/Dokumentationen/Cloud_physics/wolken.pdf">cloud
3037physics module</a> (pdf-file, only in German).<br>
3038
3039
3040
3041
3042
3043
3044 <br>
3045
3046
3047
3048
3049
3050
3051
3052This condensation scheme is not allowed if cloud droplets are simulated
3053explicitly (see <a href="#cloud_droplets">cloud_droplets</a>).<br>
3054
3055
3056
3057
3058
3059
3060
3061      </td>
3062
3063
3064
3065
3066
3067
3068 </tr>
3069
3070
3071
3072
3073
3074
3075 <tr>
3076
3077
3078
3079
3080
3081
3082 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="conserve_volume_flow"></a>conserve_volume_flow</span></td>
3083
3084
3085
3086
3087
3088
3089
3090      <td style="vertical-align: top;">L</td>
3091
3092
3093
3094
3095
3096
3097 <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
3098
3099
3100
3101
3102
3103
3104 <td>Conservation
3105of volume flow in x- and y-direction.<br>
3106
3107
3108
3109
3110
3111
3112 <br>
3113
3114
3115
3116
3117
3118
3119 <span style="font-weight: bold;">conserve_volume_flow</span>
3120= <span style="font-style: italic;">.TRUE.</span>
3121guarantees that the volume flow through the xz- or yz-cross-section of
3122the total model domain remains constant (equal to the initial value at
3123t=0) throughout the run.<br>
3124
3125
3126
3127
3128
3129
3130
3131      </td>
3132
3133
3134
3135
3136
3137
3138 </tr>
3139
3140
3141
3142
3143
3144
3145 <tr>
3146
3147      <td style="vertical-align: top;"><a name="cthf"></a><span style="font-weight: bold;">cthf</span></td>
3148
3149      <td style="vertical-align: top;">R</td>
3150
3151      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3152
3153      <td style="vertical-align: top;">Average heat flux that is prescribed at the top of the plant canopy.<br>
3154
3155
3156      <br>
3157
3158
3159If <a href="../../../../../DEVELOPER_VERSION/chapter_4.1_adjusted.html#plant_canopy">plant_canopy</a> is set <span style="font-style: italic;">.T.</span>, the user can prescribe a heat flux at the top of the plant canopy.<br>
3160
3161
3162It is assumed that solar radiation penetrates the canopy and warms the
3163foliage which, in turn, warms the air in contact with it. <br>
3164
3165
3166Note: Instead of using the value prescribed by <a href="../../../../../DEVELOPER_VERSION/chapter_4.1_adjusted.html#surface_heatflux">surface_heatflux</a>,
3167the near surface heat flux is determined from an exponential function
3168that is dependent on the cumulative leaf_area_index (Shaw and Schumann
3169(1992, Boundary Layer Meteorol., 61, 47-64)).</td>
3170
3171    </tr>
3172
3173    <tr>
3174
3175
3176
3177
3178
3179
3180 <td style="vertical-align: top;"> 
3181     
3182     
3183     
3184     
3185     
3186     
3187      <p><a name="cut_spline_overshoot"></a><b>cut_spline_overshoot</b></p>
3188
3189
3190
3191
3192
3193
3194
3195      </td>
3196
3197
3198
3199
3200
3201
3202 <td style="vertical-align: top;">L</td>
3203
3204
3205
3206
3207
3208
3209
3210      <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span></td>
3211
3212
3213
3214
3215
3216
3217 <td style="vertical-align: top;"> 
3218     
3219     
3220     
3221     
3222     
3223     
3224      <p>Cuts off of
3225so-called overshoots, which can occur with the
3226upstream-spline scheme.&nbsp; </p>
3227
3228
3229
3230
3231
3232
3233 
3234     
3235     
3236     
3237     
3238     
3239     
3240      <p><font color="#000000">The cubic splines tend to overshoot in
3241case of discontinuous changes of variables between neighbouring grid
3242points.</font><font color="#ff0000"> </font><font color="#000000">This
3243may lead to errors in calculating the advection tendency.</font>
3244Choice
3245of <b>cut_spline_overshoot</b> = <i>.TRUE.</i>
3246(switched on by
3247default)
3248allows variable values not to exceed an interval defined by the
3249respective adjacent grid points. This interval can be adjusted
3250seperately for every prognostic variable (see initialization parameters
3251      <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>,
3252etc.). This might be necessary in case that the
3253default interval has a non-tolerable effect on the model
3254results.&nbsp; </p>
3255
3256
3257
3258
3259
3260
3261 
3262     
3263     
3264     
3265     
3266     
3267     
3268      <p>Overshoots may also be removed
3269using the parameters <a href="#ups_limit_e">ups_limit_e</a>,
3270      <a href="#ups_limit_pt">ups_limit_pt</a>,
3271etc. as well as by applying a long-filter (see <a href="#long_filter_factor">long_filter_factor</a>).</p>
3272
3273
3274
3275
3276
3277
3278
3279      </td>
3280
3281
3282
3283
3284
3285
3286 </tr>
3287
3288
3289
3290
3291
3292
3293 <tr>
3294
3295
3296
3297
3298
3299
3300 <td style="vertical-align: top;"> 
3301     
3302     
3303     
3304     
3305     
3306     
3307      <p><a name="damp_level_1d"></a><b>damp_level_1d</b></p>
3308
3309
3310
3311
3312
3313
3314
3315      </td>
3316
3317
3318
3319
3320
3321
3322 <td style="vertical-align: top;">R</td>
3323
3324
3325
3326
3327
3328
3329
3330      <td style="vertical-align: top;"><span style="font-style: italic;">zu(nz+1)</span></td>
3331
3332
3333
3334
3335
3336
3337
3338      <td style="vertical-align: top;"> 
3339     
3340     
3341     
3342     
3343     
3344     
3345      <p>Height where
3346the damping layer begins in the 1d-model
3347(in m).&nbsp; </p>
3348
3349
3350
3351
3352
3353
3354 
3355     
3356     
3357     
3358     
3359     
3360     
3361      <p>This parameter is used to
3362switch on a damping layer for the
33631d-model, which is generally needed for the damping of inertia
3364oscillations. Damping is done by gradually increasing the value
3365of the eddy diffusivities about 10% per vertical grid level
3366(starting with the value at the height given by <b>damp_level_1d</b>,
3367or possibly from the next grid pint above), i.e. K<sub>m</sub>(k+1)
3368=
33691.1 * K<sub>m</sub>(k).
3370The values of K<sub>m</sub> are limited to 10 m**2/s at
3371maximum.&nbsp; <br>
3372
3373
3374
3375
3376
3377
3378
3379This parameter only comes into effect if the 1d-model is switched on
3380for
3381the initialization of the 3d-model using <a href="#initializing_actions">initializing_actions</a>
3382= <span style="font-style: italic;">'set_1d-model_profiles'</span>.
3383      <br>
3384
3385
3386
3387
3388
3389
3390 </p>
3391
3392
3393
3394
3395
3396
3397 </td>
3398
3399
3400
3401
3402
3403
3404 </tr>
3405
3406
3407
3408
3409
3410
3411 <tr>
3412
3413
3414
3415
3416
3417
3418 <td style="vertical-align: top;"><a name="dissipation_1d"></a><span style="font-weight: bold;">dissipation_1d</span><br>
3419
3420
3421
3422
3423
3424
3425
3426      </td>
3427
3428
3429
3430
3431
3432
3433 <td style="vertical-align: top;">C*20<br>
3434
3435
3436
3437
3438
3439
3440
3441      </td>
3442
3443
3444
3445
3446
3447
3448 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
3449
3450
3451
3452
3453
3454
3455 <span style="font-style: italic;">model'</span><br>
3456
3457
3458
3459
3460
3461
3462 </td>
3463
3464
3465
3466
3467
3468
3469
3470      <td style="vertical-align: top;">Calculation method for
3471the energy dissipation term in the TKE equation of the 1d-model.<br>
3472
3473
3474
3475
3476
3477
3478
3479      <br>
3480
3481
3482
3483
3484
3485
3486
3487By default the dissipation is calculated as in the 3d-model using diss
3488= (0.19 + 0.74 * l / l_grid) * e**1.5 / l.<br>
3489
3490
3491
3492
3493
3494
3495 <br>
3496
3497
3498
3499
3500
3501
3502
3503Setting <span style="font-weight: bold;">dissipation_1d</span>
3504= <span style="font-style: italic;">'detering'</span>
3505forces the dissipation to be calculated as diss = 0.064 * e**1.5 / l.<br>
3506
3507
3508
3509
3510
3511
3512
3513      </td>
3514
3515
3516
3517
3518
3519
3520 </tr>
3521
3522
3523
3524
3525
3526
3527
3528    <tr>
3529
3530      <td style="vertical-align: top;"><a name="drag_coefficient"></a><span style="font-weight: bold;">drag_coefficient</span></td>
3531
3532      <td style="vertical-align: top;">R</td>
3533
3534      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3535
3536      <td style="vertical-align: top;">Drag coefficient used in the plant canopy model.<br>
3537
3538      <br>
3539
3540This parameter has to be non-zero, if the parameter <a href="#plant_canopy">plant_canopy</a> is set <span style="font-style: italic;">.T.</span>.</td>
3541
3542    </tr>
3543
3544    <tr>
3545
3546
3547
3548
3549
3550
3551 <td style="vertical-align: top;"> 
3552     
3553     
3554     
3555     
3556     
3557     
3558      <p><a name="dt"></a><b>dt</b></p>
3559
3560
3561
3562
3563
3564
3565 </td>
3566
3567
3568
3569
3570
3571
3572
3573      <td style="vertical-align: top;">R</td>
3574
3575
3576
3577
3578
3579
3580 <td style="vertical-align: top;"><span style="font-style: italic;">variable</span></td>
3581
3582
3583
3584
3585
3586
3587
3588      <td style="vertical-align: top;"> 
3589     
3590     
3591     
3592     
3593     
3594     
3595      <p>Time step for
3596the 3d-model (in s).&nbsp; </p>
3597
3598
3599
3600
3601
3602
3603 
3604     
3605     
3606     
3607     
3608     
3609     
3610      <p>By default, (i.e.
3611if a Runge-Kutta scheme is used, see <a href="#timestep_scheme">timestep_scheme</a>)
3612the value of the time step is calculating after each time step
3613(following the time step criteria) and
3614used for the next step.</p>
3615
3616
3617
3618
3619
3620
3621 
3622     
3623     
3624     
3625     
3626     
3627     
3628      <p>If the user assigns <b>dt</b>
3629a value, then the time step is
3630fixed to this value throughout the whole run (whether it fulfills the
3631time step
3632criteria or not). However, changes are allowed for restart runs,
3633because <b>dt</b> can also be used as a <a href="chapter_4.2.html#dt_laufparameter">run
3634parameter</a>.&nbsp; </p>
3635
3636
3637
3638
3639
3640
3641 
3642     
3643     
3644     
3645     
3646     
3647     
3648      <p>In case that the
3649calculated time step meets the condition<br>
3650
3651
3652
3653
3654
3655
3656 </p>
3657
3658
3659
3660
3661
3662
3663 
3664     
3665     
3666     
3667     
3668     
3669     
3670      <ul>
3671
3672
3673
3674
3675
3676
3677
3678       
3679       
3680       
3681       
3682       
3683       
3684        <p><b>dt</b> &lt; 0.00001 * <a href="chapter_4.2.html#dt_max">dt_max</a> (with dt_max
3685= 20.0)</p>
3686
3687
3688
3689
3690
3691
3692 
3693     
3694     
3695     
3696     
3697     
3698     
3699      </ul>
3700
3701
3702
3703
3704
3705
3706 
3707     
3708     
3709     
3710     
3711     
3712     
3713      <p>the simulation will be
3714aborted. Such situations usually arise
3715in case of any numerical problem / instability which causes a
3716non-realistic increase of the wind speed.&nbsp; </p>
3717
3718
3719
3720
3721
3722
3723 
3724     
3725     
3726     
3727     
3728     
3729     
3730      <p>A
3731small time step due to a large mean horizontal windspeed
3732speed may be enlarged by using a coordinate transformation (see <a href="#galilei_transformation">galilei_transformation</a>),
3733in order to spare CPU time.<br>
3734
3735
3736
3737
3738
3739
3740 </p>
3741
3742
3743
3744
3745
3746
3747 
3748     
3749     
3750     
3751     
3752     
3753     
3754      <p>If the
3755leapfrog timestep scheme is used (see <a href="#timestep_scheme">timestep_scheme</a>)
3756a temporary time step value dt_new is calculated first, with dt_new = <a href="chapter_4.2.html#fcl_factor">cfl_factor</a>
3757* dt_crit where dt_crit is the maximum timestep allowed by the CFL and
3758diffusion condition. Next it is examined whether dt_new exceeds or
3759falls below the
3760value of the previous timestep by at
3761least +5 % / -2%. If it is smaller, <span style="font-weight: bold;">dt</span>
3762= dt_new is immediately used for the next timestep. If it is larger,
3763then <span style="font-weight: bold;">dt </span>=
37641.02 * dt_prev
3765(previous timestep) is used as the new timestep, however the time
3766step is only increased if the last change of the time step is dated
3767back at
3768least 30 iterations. If dt_new is located in the interval mentioned
3769above, then dt
3770does not change at all. By doing so, permanent time step changes as
3771well as large
3772sudden changes (increases) in the time step are avoided.</p>
3773
3774
3775
3776
3777
3778
3779 </td>
3780
3781
3782
3783
3784
3785
3786
3787    </tr>
3788
3789
3790
3791
3792
3793
3794 <tr>
3795
3796
3797
3798
3799
3800
3801 <td style="vertical-align: top;">
3802     
3803     
3804     
3805     
3806     
3807     
3808      <p><a name="dt_pr_1d"></a><b>dt_pr_1d</b></p>
3809
3810
3811
3812
3813
3814
3815
3816      </td>
3817
3818
3819
3820
3821
3822
3823 <td style="vertical-align: top;">R</td>
3824
3825
3826
3827
3828
3829
3830
3831      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
3832
3833
3834
3835
3836
3837
3838
3839      <td style="vertical-align: top;"> 
3840     
3841     
3842     
3843     
3844     
3845     
3846      <p>Temporal
3847interval of vertical profile output of the 1D-model
3848(in s).&nbsp; </p>
3849
3850
3851
3852
3853
3854
3855 
3856     
3857     
3858     
3859     
3860     
3861     
3862      <p>Data are written in ASCII
3863format to file <a href="chapter_3.4.html#LIST_PROFIL_1D">LIST_PROFIL_1D</a>.
3864This parameter is only in effect if the 1d-model has been switched on
3865for the
3866initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
3867= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
3868
3869
3870
3871
3872
3873
3874
3875      </td>
3876
3877
3878
3879
3880
3881
3882 </tr>
3883
3884
3885
3886
3887
3888
3889 <tr>
3890
3891
3892
3893
3894
3895
3896 <td style="vertical-align: top;"> 
3897     
3898     
3899     
3900     
3901     
3902     
3903      <p><a name="dt_run_control_1d"></a><b>dt_run_control_1d</b></p>
3904
3905
3906
3907
3908
3909
3910
3911      </td>
3912
3913
3914
3915
3916
3917
3918 <td style="vertical-align: top;">R</td>
3919
3920
3921
3922
3923
3924
3925
3926      <td style="vertical-align: top;"><span style="font-style: italic;">60.0</span></td>
3927
3928
3929
3930
3931
3932
3933 <td style="vertical-align: top;"> 
3934     
3935     
3936     
3937     
3938     
3939     
3940      <p>Temporal interval of
3941runtime control output of the 1d-model
3942(in s).&nbsp; </p>
3943
3944
3945
3946
3947
3948
3949 
3950     
3951     
3952     
3953     
3954     
3955     
3956      <p>Data are written in ASCII
3957format to file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
3958This parameter is only in effect if the 1d-model is switched on for the
3959initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
3960= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
3961
3962
3963
3964
3965
3966
3967
3968      </td>
3969
3970
3971
3972
3973
3974
3975 </tr>
3976
3977
3978
3979
3980
3981
3982 <tr>
3983
3984
3985
3986
3987
3988
3989 <td style="vertical-align: top;"> 
3990     
3991     
3992     
3993     
3994     
3995     
3996      <p><a name="dx"></a><b>dx</b></p>
3997
3998
3999
4000
4001
4002
4003
4004      </td>
4005
4006
4007
4008
4009
4010
4011 <td style="vertical-align: top;">R</td>
4012
4013
4014
4015
4016
4017
4018
4019      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4020
4021
4022
4023
4024
4025
4026 <td style="vertical-align: top;"> 
4027     
4028     
4029     
4030     
4031     
4032     
4033      <p>Horizontal grid
4034spacing along the x-direction (in m).&nbsp; </p>
4035
4036
4037
4038
4039
4040
4041 
4042     
4043     
4044     
4045     
4046     
4047     
4048      <p>Along
4049x-direction only a constant grid spacing is allowed.</p>
4050
4051
4052
4053
4054
4055
4056     
4057     
4058     
4059     
4060     
4061     
4062      <p>For <a href="chapter_3.8.html">coupled runs</a> this parameter must be&nbsp;equal in both parameter files <a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2"><span style="font-family: mon;"></span>PARIN</font></a>
4063and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4064
4065
4066
4067
4068
4069
4070 </td>
4071
4072
4073
4074
4075
4076
4077
4078    </tr>
4079
4080
4081
4082
4083
4084
4085 <tr>
4086
4087
4088
4089
4090
4091
4092 <td style="vertical-align: top;">
4093     
4094     
4095     
4096     
4097     
4098     
4099      <p><a name="dy"></a><b>dy</b></p>
4100
4101
4102
4103
4104
4105
4106
4107      </td>
4108
4109
4110
4111
4112
4113
4114 <td style="vertical-align: top;">R</td>
4115
4116
4117
4118
4119
4120
4121
4122      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4123
4124
4125
4126
4127
4128
4129 <td style="vertical-align: top;"> 
4130     
4131     
4132     
4133     
4134     
4135     
4136      <p>Horizontal grid
4137spacing along the y-direction (in m).&nbsp; </p>
4138
4139
4140
4141
4142
4143
4144 
4145     
4146     
4147     
4148     
4149     
4150     
4151      <p>Along y-direction only a constant grid spacing is allowed.</p>
4152
4153
4154
4155
4156
4157
4158     
4159     
4160     
4161     
4162     
4163     
4164      <p>For <a href="chapter_3.8.html">coupled runs</a> this parameter must be&nbsp;equal in both parameter files <a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2"><span style="font-family: mon;"></span>PARIN</font></a>
4165and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4166
4167
4168
4169
4170
4171
4172 </td>
4173
4174
4175
4176
4177
4178
4179
4180    </tr>
4181
4182
4183
4184
4185
4186
4187 <tr>
4188
4189
4190
4191
4192
4193
4194 <td style="vertical-align: top;">
4195     
4196     
4197     
4198     
4199     
4200     
4201      <p><a name="dz"></a><b>dz</b></p>
4202
4203
4204
4205
4206
4207
4208
4209      </td>
4210
4211
4212
4213
4214
4215
4216 <td style="vertical-align: top;">R</td>
4217
4218
4219
4220
4221
4222
4223
4224      <td style="vertical-align: top;"><br>
4225
4226
4227
4228
4229
4230
4231 </td>
4232
4233
4234
4235
4236
4237
4238 <td style="vertical-align: top;"> 
4239     
4240     
4241     
4242     
4243     
4244     
4245      <p>Vertical grid
4246spacing (in m).&nbsp; </p>
4247
4248
4249
4250
4251
4252
4253 
4254     
4255     
4256     
4257     
4258     
4259     
4260      <p>This parameter must be
4261assigned by the user, because no
4262default value is given.<br>
4263
4264
4265
4266
4267
4268
4269 </p>
4270
4271
4272
4273
4274
4275
4276 
4277     
4278     
4279     
4280     
4281     
4282     
4283      <p>By default, the
4284model uses constant grid spacing along z-direction, but it can be
4285stretched using the parameters <a href="#dz_stretch_level">dz_stretch_level</a>
4286and <a href="#dz_stretch_factor">dz_stretch_factor</a>.
4287In case of stretching, a maximum allowed grid spacing can be given by <a href="#dz_max">dz_max</a>.<br>
4288
4289
4290
4291
4292
4293
4294 </p>
4295
4296
4297
4298
4299
4300
4301 
4302     
4303     
4304     
4305     
4306     
4307     
4308      <p>Assuming
4309a constant <span style="font-weight: bold;">dz</span>,
4310the scalar levels (zu) are calculated directly by:&nbsp; </p>
4311
4312
4313
4314
4315
4316
4317
4318     
4319     
4320     
4321     
4322     
4323     
4324      <ul>
4325
4326
4327
4328
4329
4330
4331 
4332       
4333       
4334       
4335       
4336       
4337       
4338        <p>zu(0) = - dz * 0.5&nbsp; <br>
4339
4340
4341
4342
4343
4344
4345
4346zu(1) = dz * 0.5</p>
4347
4348
4349
4350
4351
4352
4353 
4354     
4355     
4356     
4357     
4358     
4359     
4360      </ul>
4361
4362
4363
4364
4365
4366
4367 
4368     
4369     
4370     
4371     
4372     
4373     
4374      <p>The w-levels lie
4375half between them:&nbsp; </p>
4376
4377
4378
4379
4380
4381
4382 
4383     
4384     
4385     
4386     
4387     
4388     
4389      <ul>
4390
4391
4392
4393
4394
4395
4396 
4397       
4398       
4399       
4400       
4401       
4402       
4403        <p>zw(k) =
4404( zu(k) + zu(k+1) ) * 0.5</p>
4405
4406
4407
4408
4409
4410
4411 
4412     
4413     
4414     
4415     
4416     
4417     
4418      </ul>
4419
4420
4421
4422
4423
4424
4425 </td>
4426
4427
4428
4429
4430
4431
4432 </tr>
4433
4434
4435
4436
4437
4438
4439
4440    <tr>
4441
4442
4443
4444
4445
4446
4447      <td style="vertical-align: top;"><a name="dz_max"></a><span style="font-weight: bold;">dz_max</span></td>
4448
4449
4450
4451
4452
4453
4454      <td style="vertical-align: top;">R</td>
4455
4456
4457
4458
4459
4460
4461      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4462
4463
4464
4465
4466
4467
4468      <td style="vertical-align: top;">Allowed maximum vertical grid
4469spacing (in m).<br>
4470
4471
4472
4473
4474
4475
4476      <br>
4477
4478
4479
4480
4481
4482
4483If the vertical grid is stretched
4484(see <a href="#dz_stretch_factor">dz_stretch_factor</a>
4485and <a href="#dz_stretch_level">dz_stretch_level</a>),
4486      <span style="font-weight: bold;">dz_max</span> can
4487be used to limit the vertical grid spacing.</td>
4488
4489
4490
4491
4492
4493
4494    </tr>
4495
4496
4497
4498
4499
4500
4501    <tr>
4502
4503
4504
4505
4506
4507
4508
4509      <td style="vertical-align: top;"> 
4510     
4511     
4512     
4513     
4514     
4515     
4516      <p><a name="dz_stretch_factor"></a><b>dz_stretch_factor</b></p>
4517
4518
4519
4520
4521
4522
4523
4524      </td>
4525
4526
4527
4528
4529
4530
4531 <td style="vertical-align: top;">R</td>
4532
4533
4534
4535
4536
4537
4538
4539      <td style="vertical-align: top;"><span style="font-style: italic;">1.08</span></td>
4540
4541
4542
4543
4544
4545
4546 <td style="vertical-align: top;"> 
4547     
4548     
4549     
4550     
4551     
4552     
4553      <p>Stretch factor for a
4554vertically stretched grid (see <a href="#dz_stretch_level">dz_stretch_level</a>).&nbsp;
4555      </p>
4556
4557
4558
4559
4560
4561
4562 
4563     
4564     
4565     
4566     
4567     
4568     
4569      <p>The stretch factor should not exceed a value of
4570approx. 1.10 -
45711.12, otherwise the discretization errors due to the stretched grid not
4572negligible any more. (refer Kalnay de Rivas)</p>
4573
4574
4575
4576
4577
4578
4579 </td>
4580
4581
4582
4583
4584
4585
4586 </tr>
4587
4588
4589
4590
4591
4592
4593
4594    <tr>
4595
4596
4597
4598
4599
4600
4601 <td style="vertical-align: top;"> 
4602     
4603     
4604     
4605     
4606     
4607     
4608      <p><a name="dz_stretch_level"></a><b>dz_stretch_level</b></p>
4609
4610
4611
4612
4613
4614
4615
4616      </td>
4617
4618
4619
4620
4621
4622
4623 <td style="vertical-align: top;">R</td>
4624
4625
4626
4627
4628
4629
4630
4631      <td style="vertical-align: top;"><span style="font-style: italic;">100000.0</span><br>
4632
4633
4634
4635
4636
4637
4638 </td>
4639
4640
4641
4642
4643
4644
4645
4646      <td style="vertical-align: top;"> 
4647     
4648     
4649     
4650     
4651     
4652     
4653      <p>Height level
4654above/below which the grid is to be stretched
4655vertically (in m).&nbsp; </p>
4656
4657
4658
4659
4660
4661
4662 
4663     
4664     
4665     
4666     
4667     
4668     
4669      <p>For <a href="chapter_4.1.html#ocean">ocean</a> = .F., <b>dz_stretch_level </b>is the height level (in m)&nbsp;<span style="font-weight: bold;">above </span>which the grid is to be stretched
4670vertically. The vertical grid
4671spacings <a href="#dz">dz</a>
4672above this level are calculated as&nbsp; </p>
4673
4674
4675
4676
4677
4678
4679 
4680     
4681     
4682     
4683     
4684     
4685     
4686      <ul>
4687
4688
4689
4690
4691
4692
4693 
4694       
4695       
4696       
4697       
4698       
4699       
4700        <p><b>dz</b>(k+1)
4701= <b>dz</b>(k) * <a href="#dz_stretch_factor">dz_stretch_factor</a></p>
4702
4703
4704
4705
4706
4707
4708
4709     
4710     
4711     
4712     
4713     
4714     
4715      </ul>
4716
4717
4718
4719
4720
4721
4722 
4723     
4724     
4725     
4726     
4727     
4728     
4729      <p>and used as spacings for the scalar levels (zu).
4730The
4731w-levels are then defined as:&nbsp; </p>
4732
4733
4734
4735
4736
4737
4738 
4739     
4740     
4741     
4742     
4743     
4744     
4745      <ul>
4746
4747
4748
4749
4750
4751
4752 
4753       
4754       
4755       
4756       
4757       
4758       
4759        <p>zw(k)
4760= ( zu(k) + zu(k+1) ) * 0.5.
4761
4762 
4763     
4764      </p>
4765
4766
4767
4768
4769     
4770     
4771     
4772     
4773      </ul>
4774
4775
4776
4777
4778     
4779     
4780     
4781     
4782      <p>For <a href="#ocean">ocean</a> = .T., <b>dz_stretch_level </b>is the height level (in m, negative) <span style="font-weight: bold;">below</span> which the grid is to be stretched
4783vertically. The vertical grid
4784spacings <a href="chapter_4.1.html#dz">dz</a> below this level are calculated correspondingly as
4785
4786 
4787     
4788      </p>
4789
4790
4791
4792
4793     
4794     
4795     
4796     
4797      <ul>
4798
4799
4800
4801
4802       
4803       
4804       
4805       
4806        <p><b>dz</b>(k-1)
4807= <b>dz</b>(k) * <a href="chapter_4.1.html#dz_stretch_factor">dz_stretch_factor</a>.</p>
4808
4809
4810
4811
4812     
4813     
4814     
4815     
4816      </ul>
4817
4818
4819
4820
4821
4822
4823 </td>
4824
4825
4826
4827
4828
4829
4830 </tr>
4831
4832
4833
4834
4835
4836
4837
4838    <tr>
4839
4840
4841
4842
4843
4844      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_init"></a>e_init</span></td>
4845
4846
4847
4848
4849
4850      <td style="vertical-align: top;">R</td>
4851
4852
4853
4854
4855
4856      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
4857
4858
4859
4860
4861
4862      <td>Initial subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
4863
4864
4865
4866
4867
4868
4869
4870      <br>
4871
4872
4873
4874
4875
4876
4877This
4878option prescribes an initial&nbsp;subgrid-scale TKE from which the initial diffusion coefficients K<sub>m</sub> and K<sub>h</sub> will be calculated if <span style="font-weight: bold;">e_init</span> is positive. This option only has an effect if&nbsp;<a href="#km_constant">km_constant</a> is not set.</td>
4879
4880
4881
4882
4883
4884    </tr>
4885
4886
4887
4888
4889
4890    <tr>
4891
4892
4893
4894
4895
4896
4897 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_min"></a>e_min</span></td>
4898
4899
4900
4901
4902
4903
4904
4905      <td style="vertical-align: top;">R</td>
4906
4907
4908
4909
4910
4911
4912 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
4913
4914
4915
4916
4917
4918
4919 <td>Minimum
4920subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
4921
4922
4923
4924
4925
4926
4927
4928      <br>
4929
4930
4931
4932
4933
4934
4935This
4936option&nbsp;adds artificial viscosity to the flow by ensuring that
4937the
4938subgrid-scale TKE does not fall below the minimum threshold <span style="font-weight: bold;">e_min</span>.</td>
4939
4940
4941
4942
4943
4944
4945 </tr>
4946
4947
4948
4949
4950
4951
4952
4953    <tr>
4954
4955
4956
4957
4958
4959
4960 <td style="vertical-align: top;"> 
4961     
4962     
4963     
4964     
4965     
4966     
4967      <p><a name="end_time_1d"></a><b>end_time_1d</b></p>
4968
4969
4970
4971
4972
4973
4974
4975      </td>
4976
4977
4978
4979
4980
4981
4982 <td style="vertical-align: top;">R</td>
4983
4984
4985
4986
4987
4988
4989
4990      <td style="vertical-align: top;"><span style="font-style: italic;">864000.0</span><br>
4991
4992
4993
4994
4995
4996
4997 </td>
4998
4999
5000
5001
5002
5003
5004
5005      <td style="vertical-align: top;"> 
5006     
5007     
5008     
5009     
5010     
5011     
5012      <p>Time to be
5013simulated for the 1d-model (in s).&nbsp; </p>
5014
5015
5016
5017
5018
5019
5020 
5021     
5022     
5023     
5024     
5025     
5026     
5027      <p>The
5028default value corresponds to a simulated time of 10 days.
5029Usually, after such a period the inertia oscillations have completely
5030decayed and the solution of the 1d-model can be regarded as stationary
5031(see <a href="#damp_level_1d">damp_level_1d</a>).
5032This parameter is only in effect if the 1d-model is switched on for the
5033initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
5034= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
5035
5036
5037
5038
5039
5040
5041
5042      </td>
5043
5044
5045
5046
5047
5048
5049 </tr>
5050
5051
5052
5053
5054
5055
5056 <tr>
5057
5058
5059
5060
5061
5062
5063 <td style="vertical-align: top;"> 
5064     
5065     
5066     
5067     
5068     
5069     
5070      <p><a name="fft_method"></a><b>fft_method</b></p>
5071
5072
5073
5074
5075
5076
5077
5078      </td>
5079
5080
5081
5082
5083
5084
5085 <td style="vertical-align: top;">C * 20</td>
5086
5087
5088
5089
5090
5091
5092
5093      <td style="vertical-align: top;"><span style="font-style: italic;">'system-</span><br style="font-style: italic;">
5094
5095
5096
5097
5098
5099
5100 <span style="font-style: italic;">specific'</span></td>
5101
5102
5103
5104
5105
5106
5107
5108      <td style="vertical-align: top;"> 
5109     
5110     
5111     
5112     
5113     
5114     
5115      <p>FFT-method to
5116be used.<br>
5117
5118
5119
5120
5121
5122
5123 </p>
5124
5125
5126
5127
5128
5129
5130 
5131     
5132     
5133     
5134     
5135     
5136     
5137      <p><br>
5138
5139
5140
5141
5142
5143
5144
5145The fast fourier transformation (FFT) is used for solving the
5146perturbation pressure equation with a direct method (see <a href="chapter_4.2.html#psolver">psolver</a>)
5147and for calculating power spectra (see optional software packages,
5148section <a href="chapter_4.2.html#spectra_package">4.2</a>).</p>
5149
5150
5151
5152
5153
5154
5155
5156     
5157     
5158     
5159     
5160     
5161     
5162      <p><br>
5163
5164
5165
5166
5167
5168
5169
5170By default, system-specific, optimized routines from external
5171vendor libraries are used. However, these are available only on certain
5172computers and there are more or less severe restrictions concerning the
5173number of gridpoints to be used with them.<br>
5174
5175
5176
5177
5178
5179
5180 </p>
5181
5182
5183
5184
5185
5186
5187 
5188     
5189     
5190     
5191     
5192     
5193     
5194      <p>There
5195are two other PALM internal methods available on every
5196machine (their respective source code is part of the PALM source code):</p>
5197
5198
5199
5200
5201
5202
5203
5204     
5205     
5206     
5207     
5208     
5209     
5210      <p>1.: The <span style="font-weight: bold;">Temperton</span>-method
5211from Clive Temperton (ECWMF) which is computationally very fast and
5212switched on with <b>fft_method</b> = <span style="font-style: italic;">'temperton-algorithm'</span>.
5213The number of horizontal gridpoints (nx+1, ny+1) to be used with this
5214method must be composed of prime factors 2, 3 and 5.<br>
5215
5216
5217
5218
5219
5220
5221 </p>
5222
5223
5224
5225
5226
5227
5228
52292.: The <span style="font-weight: bold;">Singleton</span>-method
5230which is very slow but has no restrictions concerning the number of
5231gridpoints to be used with, switched on with <b>fft_method</b>
5232= <span style="font-style: italic;">'singleton-algorithm'</span>.
5233      </td>
5234
5235
5236
5237
5238
5239
5240 </tr>
5241
5242
5243
5244
5245
5246
5247 <tr>
5248
5249
5250
5251
5252
5253
5254 <td style="vertical-align: top;"> 
5255     
5256     
5257     
5258     
5259     
5260     
5261      <p><a name="galilei_transformation"></a><b>galilei_transformation</b></p>
5262
5263
5264
5265
5266
5267
5268
5269      </td>
5270
5271
5272
5273
5274
5275
5276 <td style="vertical-align: top;">L</td>
5277
5278
5279
5280
5281
5282
5283
5284      <td style="vertical-align: top;"><i>.F.</i></td>
5285
5286
5287
5288
5289
5290
5291
5292      <td style="vertical-align: top;">Application of a
5293Galilei-transformation to the
5294coordinate
5295system of the model.<br>
5296
5297
5298
5299
5300
5301
5302     
5303     
5304     
5305     
5306     
5307     
5308      <p>With <b>galilei_transformation</b>
5309= <i>.T.,</i> a so-called
5310Galilei-transformation is switched on which ensures that the coordinate
5311system of the model is moved along with the geostrophical wind.
5312Alternatively, the model domain can be moved along with the averaged
5313horizontal wind (see <a href="#use_ug_for_galilei_tr">use_ug_for_galilei_tr</a>,
5314this can and will naturally change in time). With this method,
5315numerical inaccuracies of the Piascek - Williams - scheme (concerns in
5316particular the momentum advection) are minimized. Beyond that, in the
5317majority of cases the lower relative velocities in the moved system
5318permit a larger time step (<a href="#dt">dt</a>).
5319Switching the transformation on is only worthwhile if the geostrophical
5320wind (ug, vg)
5321and the averaged horizontal wind clearly deviate from the value 0. In
5322each case, the distance the coordinate system has been moved is written
5323to the file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.&nbsp;
5324      </p>
5325
5326
5327
5328
5329
5330
5331 
5332     
5333     
5334     
5335     
5336     
5337     
5338      <p>Non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
5339and <a href="#bc_ns">bc_ns</a>), the specification
5340of a gestrophic
5341wind that is not constant with height
5342as well as e.g. stationary inhomogeneities at the bottom boundary do
5343not allow the use of this transformation.</p>
5344
5345
5346
5347
5348
5349
5350 </td>
5351
5352
5353
5354
5355
5356
5357 </tr>
5358
5359
5360
5361
5362
5363
5364
5365    <tr>
5366
5367
5368
5369
5370
5371
5372 <td style="vertical-align: top;"> 
5373     
5374     
5375     
5376     
5377     
5378     
5379      <p><a name="grid_matching"></a><b>grid_matching</b></p>
5380
5381
5382
5383
5384
5385
5386
5387      </td>
5388
5389
5390
5391
5392
5393
5394 <td style="vertical-align: top;">C * 6</td>
5395
5396
5397
5398
5399
5400
5401
5402      <td style="vertical-align: top;"><span style="font-style: italic;">'match'</span></td>
5403
5404
5405
5406
5407
5408
5409 <td style="vertical-align: top;">Variable to adjust the
5410subdomain
5411sizes in parallel runs.<br>
5412
5413
5414
5415
5416
5417
5418 <br>
5419
5420
5421
5422
5423
5424
5425
5426For <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>,
5427the subdomains are forced to have an identical
5428size on all processors. In this case the processor numbers in the
5429respective directions of the virtual processor net must fulfill certain
5430divisor conditions concerning the grid point numbers in the three
5431directions (see <a href="#nx">nx</a>, <a href="#ny">ny</a>
5432and <a href="#nz">nz</a>).
5433Advantage of this method is that all PEs bear the same computational
5434load.<br>
5435
5436
5437
5438
5439
5440
5441 <br>
5442
5443
5444
5445
5446
5447
5448
5449There is no such restriction by default, because then smaller
5450subdomains are allowed on those processors which
5451form the right and/or north boundary of the virtual processor grid. On
5452all other processors the subdomains are of same size. Whether smaller
5453subdomains are actually used, depends on the number of processors and
5454the grid point numbers used. Information about the respective settings
5455are 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>
5456
5457
5458
5459
5460
5461
5462
5463      <br>
5464
5465
5466
5467
5468
5469
5470
5471When 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>)
5472only <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>
5473is allowed.<br>
5474
5475
5476
5477
5478
5479
5480 <br>
5481
5482
5483
5484
5485
5486
5487 <b>Note:</b><br>
5488
5489
5490
5491
5492
5493
5494
5495In some cases for small processor numbers there may be a very bad load
5496balancing among the
5497processors which may reduce the performance of the code.</td>
5498
5499
5500
5501
5502
5503
5504 </tr>
5505
5506
5507
5508
5509
5510
5511
5512    <tr>
5513
5514
5515
5516
5517
5518
5519 <td style="vertical-align: top;"><a name="inflow_disturbance_begin"></a><b>inflow_disturbance_<br>
5520
5521
5522
5523
5524
5525
5526
5527begin</b></td>
5528
5529
5530
5531
5532
5533
5534 <td style="vertical-align: top;">I</td>
5535
5536
5537
5538
5539
5540
5541
5542      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(10,</span><br style="font-style: italic;">
5543
5544
5545
5546
5547
5548
5549 <span style="font-style: italic;">nx/2 or ny/2)</span></td>
5550
5551
5552
5553
5554
5555
5556
5557      <td style="vertical-align: top;">Lower
5558limit of the horizontal range for which random perturbations are to be
5559imposed on the horizontal velocity field (gridpoints).<br>
5560
5561
5562
5563
5564
5565
5566 <br>
5567
5568
5569
5570
5571
5572
5573
5574If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5575or <a href="#bc_ns">bc_ns</a>),
5576this parameter gives the gridpoint number (counted horizontally from
5577the inflow)&nbsp; from which on perturbations are imposed on the
5578horizontal velocity field. Perturbations must be switched on with
5579parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5580
5581
5582
5583
5584
5585
5586
5587    </tr>
5588
5589
5590
5591
5592
5593
5594 <tr>
5595
5596
5597
5598
5599
5600
5601 <td style="vertical-align: top;"><a name="inflow_disturbance_end"></a><b>inflow_disturbance_<br>
5602
5603
5604
5605
5606
5607
5608
5609end</b></td>
5610
5611
5612
5613
5614
5615
5616 <td style="vertical-align: top;">I</td>
5617
5618
5619
5620
5621
5622
5623
5624      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(100,</span><br style="font-style: italic;">
5625
5626
5627
5628
5629
5630
5631 <span style="font-style: italic;">3/4*nx or</span><br style="font-style: italic;">
5632
5633
5634
5635
5636
5637
5638 <span style="font-style: italic;">3/4*ny)</span></td>
5639
5640
5641
5642
5643
5644
5645 <td style="vertical-align: top;">Upper
5646limit of the horizontal range for which random perturbations are
5647to be imposed on the horizontal velocity field (gridpoints).<br>
5648
5649
5650
5651
5652
5653
5654 <br>
5655
5656
5657
5658
5659
5660
5661
5662If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5663or <a href="#bc_ns">bc_ns</a>),
5664this parameter gives the gridpoint number (counted horizontally from
5665the inflow)&nbsp; unto which perturbations are imposed on the
5666horizontal
5667velocity field. Perturbations must be switched on with parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5668
5669
5670
5671
5672
5673
5674
5675    </tr>
5676
5677
5678
5679
5680
5681
5682 <tr>
5683
5684
5685
5686
5687
5688
5689 <td style="vertical-align: top;">
5690     
5691     
5692     
5693     
5694     
5695     
5696      <p><a name="initializing_actions"></a><b>initializing_actions</b></p>
5697
5698
5699
5700
5701
5702
5703
5704      </td>
5705
5706
5707
5708
5709
5710
5711 <td style="vertical-align: top;">C * 100</td>
5712
5713
5714
5715
5716
5717
5718
5719      <td style="vertical-align: top;"><br>
5720
5721
5722
5723
5724
5725
5726 </td>
5727
5728
5729
5730
5731
5732
5733 <td style="vertical-align: top;"> 
5734     
5735     
5736     
5737     
5738     
5739     
5740      <p style="font-style: normal;">Initialization actions
5741to be carried out.&nbsp; </p>
5742
5743
5744
5745
5746
5747
5748 
5749     
5750     
5751     
5752     
5753     
5754     
5755      <p style="font-style: normal;">This parameter does not have a
5756default value and therefore must be assigned with each model run. For
5757restart runs <b>initializing_actions</b> = <span style="font-style: italic;">'read_restart_data'</span>
5758must be set. For the initial run of a job chain the following values
5759are allowed:&nbsp; </p>
5760
5761
5762
5763
5764
5765
5766 
5767     
5768     
5769     
5770     
5771     
5772     
5773      <p style="font-style: normal;"><span style="font-style: italic;">'set_constant_profiles'</span>
5774      </p>
5775
5776
5777
5778
5779
5780
5781 
5782     
5783     
5784     
5785     
5786     
5787     
5788      <ul>
5789
5790
5791
5792
5793
5794
5795 
5796       
5797       
5798       
5799       
5800       
5801       
5802        <p>A horizontal wind profile consisting
5803of linear sections (see <a href="#ug_surface">ug_surface</a>,
5804        <a href="#ug_vertical_gradient">ug_vertical_gradient</a>,
5805        <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>
5806and <a href="#vg_surface">vg_surface</a>, <a href="#vg_vertical_gradient">vg_vertical_gradient</a>,
5807        <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
5808respectively) as well as a vertical temperature (humidity) profile
5809consisting of
5810linear sections (see <a href="#pt_surface">pt_surface</a>,
5811        <a href="#pt_vertical_gradient">pt_vertical_gradient</a>,
5812        <a href="#q_surface">q_surface</a>
5813and <a href="#q_vertical_gradient">q_vertical_gradient</a>)
5814are assumed as initial profiles. The subgrid-scale TKE is set to 0 but K<sub>m</sub>
5815and K<sub>h</sub> are set to very small values because
5816otherwise no TKE
5817would be generated.</p>
5818
5819
5820
5821
5822
5823
5824 
5825     
5826     
5827     
5828     
5829     
5830     
5831      </ul>
5832
5833
5834
5835
5836
5837
5838 
5839     
5840     
5841     
5842     
5843     
5844     
5845      <p style="font-style: italic;">'set_1d-model_profiles' </p>
5846
5847
5848
5849
5850
5851
5852
5853     
5854     
5855     
5856     
5857     
5858     
5859      <ul>
5860
5861
5862
5863
5864
5865
5866 
5867       
5868       
5869       
5870       
5871       
5872       
5873        <p>The arrays of the 3d-model are initialized with
5874the
5875(stationary) solution of the 1d-model. These are the variables e, kh,
5876km, u, v and with Prandtl layer switched on rif, us, usws, vsws. The
5877temperature (humidity) profile consisting of linear sections is set as
5878for 'set_constant_profiles' and assumed as constant in time within the
58791d-model. For steering of the 1d-model a set of parameters with suffix
5880"_1d" (e.g. <a href="#end_time_1d">end_time_1d</a>,
5881        <a href="#damp_level_1d">damp_level_1d</a>)
5882is available.</p>
5883
5884
5885
5886
5887
5888
5889 
5890     
5891     
5892     
5893     
5894     
5895     
5896      </ul>
5897
5898
5899
5900
5901
5902
5903 
5904     
5905     
5906     
5907     
5908     
5909     
5910      <p><span style="font-style: italic;">'by_user'</span></p>
5911
5912
5913
5914
5915
5916
5917     
5918     
5919     
5920     
5921     
5922     
5923      <p style="margin-left: 40px;">The initialization of the arrays
5924of the 3d-model is under complete control of the user and has to be
5925done in routine <a href="chapter_3.5.1.html#user_init_3d_model">user_init_3d_model</a>
5926of the user-interface.<span style="font-style: italic;"></span></p>
5927
5928
5929
5930
5931
5932
5933     
5934     
5935     
5936     
5937     
5938     
5939      <p><span style="font-style: italic;">'initialize_vortex'</span>
5940      </p>
5941
5942
5943
5944
5945
5946
5947 
5948     
5949     
5950     
5951     
5952     
5953     
5954      <div style="margin-left: 40px;">The initial
5955velocity field of the
59563d-model corresponds to a
5957Rankine-vortex with vertical axis. This setting may be used to test
5958advection 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>)
5959are necessary. In order not to distort the vortex, an initial
5960horizontal wind profile constant
5961with height is necessary (to be set by <b>initializing_actions</b>
5962= <span style="font-style: italic;">'set_constant_profiles'</span>)
5963and some other conditions have to be met (neutral stratification,
5964diffusion must be
5965switched off, see <a href="#km_constant">km_constant</a>).
5966The center of the vortex is located at jc = (nx+1)/2. It
5967extends from k = 0 to k = nz+1. Its radius is 8 * <a href="#dx">dx</a>
5968and the exponentially decaying part ranges to 32 * <a href="#dx">dx</a>
5969(see init_rankine.f90). </div>
5970
5971
5972
5973
5974
5975
5976 
5977     
5978     
5979     
5980     
5981     
5982     
5983      <p><span style="font-style: italic;">'initialize_ptanom'</span>
5984      </p>
5985
5986
5987
5988
5989
5990
5991 
5992     
5993     
5994     
5995     
5996     
5997     
5998      <ul>
5999
6000
6001
6002
6003
6004
6005 
6006       
6007       
6008       
6009       
6010       
6011       
6012        <p>A 2d-Gauss-like shape disturbance
6013(x,y) is added to the
6014initial temperature field with radius 10.0 * <a href="#dx">dx</a>
6015and center at jc = (nx+1)/2. This may be used for tests of scalar
6016advection schemes
6017(see <a href="#scalar_advec">scalar_advec</a>).
6018Such tests require a horizontal wind profile constant with hight and
6019diffusion
6020switched off (see <span style="font-style: italic;">'initialize_vortex'</span>).
6021Additionally, the buoyancy term
6022must be switched of in the equation of motion&nbsp; for w (this
6023requires the user to comment out the call of <span style="font-family: monospace;">buoyancy</span> in the
6024source code of <span style="font-family: monospace;">prognostic_equations.f90</span>).</p>
6025
6026
6027
6028
6029
6030
6031
6032     
6033     
6034     
6035     
6036     
6037     
6038      </ul>
6039
6040
6041
6042
6043
6044
6045 
6046     
6047     
6048     
6049     
6050     
6051     
6052      <p style="font-style: normal;">Values may be
6053combined, e.g. <b>initializing_actions</b> = <span style="font-style: italic;">'set_constant_profiles
6054initialize_vortex'</span>, but the values of <span style="font-style: italic;">'set_constant_profiles'</span>,
6055      <span style="font-style: italic;">'set_1d-model_profiles'</span>
6056, and <span style="font-style: italic;">'by_user'</span>
6057must not be given at the same time.</p>
6058
6059
6060
6061
6062
6063
6064 
6065     
6066     
6067     
6068     
6069     
6070     
6071      <p style="font-style: italic;"> </p>
6072
6073
6074
6075
6076
6077
6078 </td>
6079
6080
6081
6082
6083
6084
6085 </tr>
6086
6087
6088
6089
6090
6091
6092
6093    <tr>
6094
6095
6096
6097
6098
6099
6100 <td style="vertical-align: top;"> 
6101     
6102     
6103     
6104     
6105     
6106     
6107      <p><a name="km_constant"></a><b>km_constant</b></p>
6108
6109
6110
6111
6112
6113
6114
6115      </td>
6116
6117
6118
6119
6120
6121
6122 <td style="vertical-align: top;">R</td>
6123
6124
6125
6126
6127
6128
6129
6130      <td style="vertical-align: top;"><i>variable<br>
6131
6132
6133
6134
6135
6136
6137
6138(computed from TKE)</i></td>
6139
6140
6141
6142
6143
6144
6145 <td style="vertical-align: top;"> 
6146     
6147     
6148     
6149     
6150     
6151     
6152      <p>Constant eddy
6153diffusivities are used (laminar
6154simulations).&nbsp; </p>
6155
6156
6157
6158
6159
6160
6161 
6162     
6163     
6164     
6165     
6166     
6167     
6168      <p>If this parameter is
6169specified, both in the 1d and in the
61703d-model constant values for the eddy diffusivities are used in
6171space and time with K<sub>m</sub> = <b>km_constant</b>
6172and K<sub>h</sub> = K<sub>m</sub> / <a href="chapter_4.2.html#prandtl_number">prandtl_number</a>.
6173The prognostic equation for the subgrid-scale TKE is switched off.
6174Constant eddy diffusivities are only allowed with the Prandtl layer (<a href="#prandtl_layer">prandtl_layer</a>)
6175switched off.</p>
6176
6177
6178
6179
6180
6181
6182 </td>
6183
6184
6185
6186
6187
6188
6189 </tr>
6190
6191
6192
6193
6194
6195
6196 <tr>
6197
6198
6199
6200
6201
6202
6203 <td style="vertical-align: top;"> 
6204     
6205     
6206     
6207     
6208     
6209     
6210      <p><a name="km_damp_max"></a><b>km_damp_max</b></p>
6211
6212
6213
6214
6215
6216
6217
6218      </td>
6219
6220
6221
6222
6223
6224
6225 <td style="vertical-align: top;">R</td>
6226
6227
6228
6229
6230
6231
6232
6233      <td style="vertical-align: top;"><span style="font-style: italic;">0.5*(dx
6234or dy)</span></td>
6235
6236
6237
6238
6239
6240
6241 <td style="vertical-align: top;">Maximum
6242diffusivity used for filtering the velocity field in the vicinity of
6243the outflow (in m<sup>2</sup>/s).<br>
6244
6245
6246
6247
6248
6249
6250 <br>
6251
6252
6253
6254
6255
6256
6257
6258When using non-cyclic lateral boundaries (see <a href="#bc_lr">bc_lr</a>
6259or <a href="#bc_ns">bc_ns</a>),
6260a smoothing has to be applied to the
6261velocity field in the vicinity of the outflow in order to suppress any
6262reflections of outgoing disturbances. Smoothing is done by increasing
6263the eddy diffusivity along the horizontal direction which is
6264perpendicular to the outflow boundary. Only velocity components
6265parallel to the outflow boundary are filtered (e.g. v and w, if the
6266outflow is along x). Damping is applied from the bottom to the top of
6267the domain.<br>
6268
6269
6270
6271
6272
6273
6274 <br>
6275
6276
6277
6278
6279
6280
6281
6282The horizontal range of the smoothing is controlled by <a href="#outflow_damping_width">outflow_damping_width</a>
6283which defines the number of gridpoints (counted from the outflow
6284boundary) from where on the smoothing is applied. Starting from that
6285point, the eddy diffusivity is linearly increased (from zero to its
6286maximum value given by <span style="font-weight: bold;">km_damp_max</span>)
6287until half of the damping range width, from where it remains constant
6288up to the outflow boundary. If at a certain grid point the eddy
6289diffusivity calculated from the flow field is larger than as described
6290above, it is used instead.<br>
6291
6292
6293
6294
6295
6296
6297 <br>
6298
6299
6300
6301
6302
6303
6304
6305The default value of <span style="font-weight: bold;">km_damp_max</span>
6306has been empirically proven to be sufficient.</td>
6307
6308
6309
6310
6311
6312
6313 </tr>
6314
6315
6316
6317
6318
6319
6320 <tr>
6321
6322      <td style="vertical-align: top;"><a name="lad_surface"></a><span style="font-weight: bold;">lad_surface</span></td>
6323
6324      <td style="vertical-align: top;">R</td>
6325
6326      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
6327
6328      <td style="vertical-align: top;">Surface value of the leaf area density (in m<sup>2</sup>/m<sup>3</sup>).<br>
6329
6330      <br>
6331
6332This
6333parameter assigns the value of the leaf area density <span style="font-weight: bold;">lad</span> at the surface (k=0)<b>.</b> Starting from this value,
6334the leaf area density profile is constructed with <a href="chapter_4.1.html#lad_vertical_gradient">lad_vertical_gradient</a>
6335and <a href="chapter_4.1.html#lad_vertical_gradient_level">lad_vertical_gradient_level
6336      </a>.</td>
6337
6338    </tr>
6339
6340    <tr>
6341
6342      <td style="vertical-align: top;"><a name="lad_vertical_gradient"></a><span style="font-weight: bold;">lad_vertical_gradient</span></td>
6343
6344      <td style="vertical-align: top;">R (10)</td>
6345
6346      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6347
6348      <td style="vertical-align: top;">Gradient(s) of the leaf area density (in&nbsp;m<sup>2</sup>/m<sup>4</sup>).<br>
6349
6350      <br>
6351
6352     
6353      <p>This leaf area density gradient
6354holds starting from the height&nbsp;
6355level defined by <a href="chapter_4.1.html#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6356(precisely: for all uv levels k where zu(k) &gt; lad_vertical_gradient_level, lad(k) is set: lad(k) = lad(k-1) + dzu(k) * <b>lad_vertical_gradient</b>)
6357up to the level defined by <a href="#pch_index">pch_index</a>. Above that level lad(k) will automatically set to 0.0. A total of 10 different gradients for 11 height intervals (10 intervals
6358if <a href="chapter_4.1.html#lad_vertical_gradient_level">lad_vertical_gradient_level</a>(1)
6359= <i>0.0</i>) can be assigned. The leaf area density at the surface is
6360assigned via <a href="chapter_4.1.html#lad_surface">lad_surface</a>.&nbsp;
6361      </p>
6362
6363      </td>
6364
6365    </tr>
6366
6367    <tr>
6368
6369      <td style="vertical-align: top;"><a name="lad_vertical_gradient_level"></a><span style="font-weight: bold;">lad_vertical_gradient_level</span></td>
6370
6371      <td style="vertical-align: top;">R (10)</td>
6372
6373      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6374
6375      <td style="vertical-align: top;">Height level from which on the&nbsp;gradient
6376of the leaf area density defined by <a href="chapter_4.1.html#lad_vertical_gradient">lad_vertical_gradient_level</a>
6377is effective (in m).<br>
6378
6379      <br>
6380
6381The height levels have to be assigned in ascending order. The
6382default values result in a leaf area density that is constant with height uup to the top of the plant canopy layer defined by <a href="#pch_index">pch_index</a>. For the piecewise construction of temperature profiles see <a href="chapter_4.1.html#lad_vertical_gradient">lad_vertical_gradient</a>.</td>
6383
6384    </tr>
6385
6386    <tr>
6387
6388      <td style="vertical-align: top;"><a name="leaf_surface_concentration"></a><b>leaf_surface_concentration</b></td>
6389
6390      <td style="vertical-align: top;">R</td>
6391
6392      <td style="vertical-align: top;"><i>0.0</i></td>
6393
6394      <td style="vertical-align: top;">Concentration of a passive scalar at the surface of a leaf (in K m/s).<br>
6395
6396
6397      <br>
6398
6399
6400This parameter is only of importance in cases in that both, <a href="../../../../../DEVELOPER_VERSION/chapter_4.1_adjusted.html#plant_canopy">plant_canopy</a> and <a href="../../../../../DEVELOPER_VERSION/chapter_4.1_adjusted.html#passive_scalar">passive_scalar</a>, are set <span style="font-style: italic;">.T.</span>.
6401The value of the concentration of a passive scalar at the surface of a
6402leaf is required for the parametrisation of the sources and sinks of
6403scalar concentration due to the canopy.</td>
6404
6405    </tr>
6406
6407    <tr>
6408
6409
6410
6411
6412
6413
6414
6415      <td style="vertical-align: top;"> 
6416     
6417     
6418     
6419     
6420     
6421     
6422      <p><a name="long_filter_factor"></a><b>long_filter_factor</b></p>
6423
6424
6425
6426
6427
6428
6429
6430      </td>
6431
6432
6433
6434
6435
6436
6437 <td style="vertical-align: top;">R</td>
6438
6439
6440
6441
6442
6443
6444
6445      <td style="vertical-align: top;"><i>0.0</i></td>
6446
6447
6448
6449
6450
6451
6452
6453      <td style="vertical-align: top;"> 
6454     
6455     
6456     
6457     
6458     
6459     
6460      <p>Filter factor
6461for the so-called Long-filter.<br>
6462
6463
6464
6465
6466
6467
6468 </p>
6469
6470
6471
6472
6473
6474
6475 
6476     
6477     
6478     
6479     
6480     
6481     
6482      <p><br>
6483
6484
6485
6486
6487
6488
6489
6490This filter very efficiently
6491eliminates 2-delta-waves sometimes cauesed by the upstream-spline
6492scheme (see Mahrer and
6493Pielke, 1978: Mon. Wea. Rev., 106, 818-830). It works in all three
6494directions in space. A value of <b>long_filter_factor</b>
6495= <i>0.01</i>
6496sufficiently removes the small-scale waves without affecting the
6497longer waves.<br>
6498
6499
6500
6501
6502
6503
6504 </p>
6505
6506
6507
6508
6509
6510
6511 
6512     
6513     
6514     
6515     
6516     
6517     
6518      <p>By default, the filter is
6519switched off (= <i>0.0</i>).
6520It is exclusively applied to the tendencies calculated by the
6521upstream-spline scheme (see <a href="#momentum_advec">momentum_advec</a>
6522and <a href="#scalar_advec">scalar_advec</a>),
6523not to the prognostic variables themselves. At the bottom and top
6524boundary of the model domain the filter effect for vertical
65252-delta-waves is reduced. There, the amplitude of these waves is only
6526reduced by approx. 50%, otherwise by nearly 100%.&nbsp; <br>
6527
6528
6529
6530
6531
6532
6533
6534Filter factors with values &gt; <i>0.01</i> also
6535reduce the amplitudes
6536of waves with wavelengths longer than 2-delta (see the paper by Mahrer
6537and
6538Pielke, quoted above). </p>
6539
6540
6541
6542
6543
6544
6545 </td>
6546
6547
6548
6549
6550
6551
6552 </tr>
6553
6554
6555
6556
6557
6558
6559 <tr>
6560
6561
6562
6563
6564
6565
6566      <td style="vertical-align: top;"><a name="loop_optimization"></a><span style="font-weight: bold;">loop_optimization</span></td>
6567
6568
6569
6570
6571
6572
6573      <td style="vertical-align: top;">C*16</td>
6574
6575
6576
6577
6578
6579
6580      <td style="vertical-align: top;"><span style="font-style: italic;">see right</span></td>
6581
6582
6583
6584
6585
6586
6587      <td>Method used to optimize loops for solving the prognostic equations .<br>
6588
6589
6590
6591
6592
6593
6594      <br>
6595
6596
6597
6598
6599
6600
6601By
6602default, the optimization method depends on the host on which PALM is
6603running. On machines with vector-type CPUs, single 3d-loops are used to
6604calculate each tendency term of each prognostic equation, while on all
6605other machines, all prognostic equations are solved within one big loop
6606over the two horizontal indices<span style="font-family: Courier New,Courier,monospace;"> i </span>and<span style="font-family: Courier New,Courier,monospace;"> j </span>(giving a good cache uitilization).<br>
6607
6608
6609
6610
6611
6612
6613      <br>
6614
6615
6616
6617
6618
6619
6620The default behaviour can be changed by setting either <span style="font-weight: bold;">loop_optimization</span> = <span style="font-style: italic;">'vector'</span> or <span style="font-weight: bold;">loop_optimization</span> = <span style="font-style: italic;">'cache'</span>.</td>
6621
6622
6623
6624
6625
6626
6627    </tr>
6628
6629
6630
6631
6632
6633
6634    <tr>
6635
6636
6637
6638
6639
6640
6641
6642      <td style="vertical-align: top;"><a name="mixing_length_1d"></a><span style="font-weight: bold;">mixing_length_1d</span><br>
6643
6644
6645
6646
6647
6648
6649
6650      </td>
6651
6652
6653
6654
6655
6656
6657 <td style="vertical-align: top;">C*20<br>
6658
6659
6660
6661
6662
6663
6664
6665      </td>
6666
6667
6668
6669
6670
6671
6672 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
6673
6674
6675
6676
6677
6678
6679 <span style="font-style: italic;">model'</span><br>
6680
6681
6682
6683
6684
6685
6686 </td>
6687
6688
6689
6690
6691
6692
6693
6694      <td style="vertical-align: top;">Mixing length used in the
66951d-model.<br>
6696
6697
6698
6699
6700
6701
6702 <br>
6703
6704
6705
6706
6707
6708
6709
6710By default the mixing length is calculated as in the 3d-model (i.e. it
6711depends on the grid spacing).<br>
6712
6713
6714
6715
6716
6717
6718 <br>
6719
6720
6721
6722
6723
6724
6725
6726By setting <span style="font-weight: bold;">mixing_length_1d</span>
6727= <span style="font-style: italic;">'blackadar'</span>,
6728the so-called Blackadar mixing length is used (l = kappa * z / ( 1 +
6729kappa * z / lambda ) with the limiting value lambda = 2.7E-4 * u_g / f).<br>
6730
6731
6732
6733
6734
6735
6736
6737      </td>
6738
6739
6740
6741
6742
6743
6744 </tr>
6745
6746
6747
6748
6749
6750
6751 <tr>
6752
6753
6754
6755
6756
6757
6758 <td style="vertical-align: top;"> 
6759     
6760     
6761     
6762     
6763     
6764     
6765      <p><a name="humidity"></a><b>humidity</b></p>
6766
6767
6768
6769
6770
6771
6772
6773      </td>
6774
6775
6776
6777
6778
6779
6780 <td style="vertical-align: top;">L</td>
6781
6782
6783
6784
6785
6786
6787
6788      <td style="vertical-align: top;"><i>.F.</i></td>
6789
6790
6791
6792
6793
6794
6795
6796      <td style="vertical-align: top;"> 
6797     
6798     
6799     
6800     
6801     
6802     
6803      <p>Parameter to
6804switch on the prognostic equation for specific
6805humidity q.<br>
6806
6807
6808
6809
6810
6811
6812 </p>
6813
6814
6815
6816
6817
6818
6819 
6820     
6821     
6822     
6823     
6824     
6825     
6826      <p>The initial vertical
6827profile 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>
6828and <a href="chapter_4.1.html#q_vertical_gradient_level">q_vertical_gradient_level</a>.&nbsp;
6829Boundary conditions can be set via <a href="chapter_4.1.html#q_surface_initial_change">q_surface_initial_change</a>
6830and <a href="chapter_4.1.html#surface_waterflux">surface_waterflux</a>.<br>
6831
6832
6833
6834
6835
6836
6837
6838      </p>
6839
6840
6841
6842
6843
6844
6845
6846If the condensation scheme is switched on (<a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
6847= .TRUE.), q becomes the total liquid water content (sum of specific
6848humidity and liquid water content).</td>
6849
6850
6851
6852
6853
6854
6855 </tr>
6856
6857
6858
6859
6860
6861
6862
6863    <tr>
6864
6865
6866
6867
6868
6869
6870 <td style="vertical-align: top;"> 
6871     
6872     
6873     
6874     
6875     
6876     
6877      <p><a name="momentum_advec"></a><b>momentum_advec</b></p>
6878
6879
6880
6881
6882
6883
6884
6885      </td>
6886
6887
6888
6889
6890
6891
6892 <td style="vertical-align: top;">C * 10</td>
6893
6894
6895
6896
6897
6898
6899
6900      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
6901
6902
6903
6904
6905
6906
6907
6908      <td style="vertical-align: top;"> 
6909     
6910     
6911     
6912     
6913     
6914     
6915      <p>Advection
6916scheme to be used for the momentum equations.<br>
6917
6918
6919
6920
6921
6922
6923 <br>
6924
6925
6926
6927
6928
6929
6930
6931The user can choose between the following schemes:<br>
6932
6933
6934
6935
6936
6937
6938
6939&nbsp;<br>
6940
6941
6942
6943
6944
6945
6946 <br>
6947
6948
6949
6950
6951
6952
6953 <span style="font-style: italic;">'pw-scheme'</span><br>
6954
6955
6956
6957
6958
6959
6960
6961      </p>
6962
6963
6964
6965
6966
6967
6968 
6969     
6970     
6971     
6972     
6973     
6974     
6975      <div style="margin-left: 40px;">The scheme of
6976Piascek and
6977Williams (1970, J. Comp. Phys., 6,
6978392-405) with central differences in the form C3 is used.<br>
6979
6980
6981
6982
6983
6984
6985
6986If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
6987= <span style="font-style: italic;">'leapfrog+euler'</span>
6988the
6989advection scheme is - for the Euler-timestep - automatically switched
6990to an upstream-scheme.<br>
6991
6992
6993
6994
6995
6996
6997 </div>
6998
6999
7000
7001
7002
7003
7004 
7005     
7006     
7007     
7008     
7009     
7010     
7011      <p> </p>
7012
7013
7014
7015
7016
7017
7018 
7019     
7020     
7021     
7022     
7023     
7024     
7025      <p><span style="font-style: italic;">'ups-scheme'</span><br>
7026
7027
7028
7029
7030
7031
7032
7033      </p>
7034
7035
7036
7037
7038
7039
7040 
7041     
7042     
7043     
7044     
7045     
7046     
7047      <div style="margin-left: 40px;">The
7048upstream-spline scheme is
7049used
7050(see Mahrer and Pielke,
70511978: Mon. Wea. Rev., 106, 818-830). In opposite to the
7052Piascek-Williams scheme, this is characterized by much better numerical
7053features (less numerical diffusion, better preservation of flow
7054structures, e.g. vortices), but computationally it is much more
7055expensive. In
7056addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
7057= <span style="font-style: italic;">'</span><i>euler'</i>),
7058i.e. the
7059timestep accuracy is only of first order.
7060For this reason the advection of scalar variables (see <a href="#scalar_advec">scalar_advec</a>)
7061should then also be carried out with the upstream-spline scheme,
7062because otherwise the scalar variables would
7063be subject to large numerical diffusion due to the upstream
7064scheme.&nbsp; </div>
7065
7066
7067
7068
7069
7070
7071 
7072     
7073     
7074     
7075     
7076     
7077     
7078      <p style="margin-left: 40px;">Since
7079the cubic splines used tend
7080to overshoot under
7081certain circumstances, this effect must be adjusted by suitable
7082filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
7083      <a href="#long_filter_factor">long_filter_factor</a>,
7084      <a href="#ups_limit_pt">ups_limit_pt</a>, <a href="#ups_limit_u">ups_limit_u</a>, <a href="#ups_limit_v">ups_limit_v</a>, <a href="#ups_limit_w">ups_limit_w</a>).
7085This is always neccessary for runs with stable stratification,
7086even if this stratification appears only in parts of the model domain.<br>
7087
7088
7089
7090
7091
7092
7093
7094      </p>
7095
7096
7097
7098
7099
7100
7101 
7102     
7103     
7104     
7105     
7106     
7107     
7108      <div style="margin-left: 40px;">With stable
7109stratification the
7110upstream-spline scheme also
7111produces gravity waves with large amplitude, which must be
7112suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
7113
7114
7115
7116
7117
7118
7119
7120      <br>
7121
7122
7123
7124
7125
7126
7127 <span style="font-weight: bold;">Important: </span>The&nbsp;
7128upstream-spline scheme is not implemented for humidity and passive
7129scalars (see&nbsp;<a href="#humidity">humidity</a>
7130and <a href="#passive_scalar">passive_scalar</a>)
7131and requires the use of a 2d-domain-decomposition. The last conditions
7132severely restricts code optimization on several machines leading to
7133very long execution times! The scheme is also not allowed for
7134non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
7135and <a href="#bc_ns">bc_ns</a>).</div>
7136
7137
7138
7139
7140
7141
7142 </td>
7143
7144
7145
7146
7147
7148
7149
7150    </tr>
7151
7152
7153
7154
7155
7156
7157 <tr>
7158
7159
7160
7161
7162
7163
7164 <td style="vertical-align: top;"><a name="netcdf_precision"></a><span style="font-weight: bold;">netcdf_precision</span><br>
7165
7166
7167
7168
7169
7170
7171
7172      </td>
7173
7174
7175
7176
7177
7178
7179 <td style="vertical-align: top;">C*20<br>
7180
7181
7182
7183
7184
7185
7186
7187(10)<br>
7188
7189
7190
7191
7192
7193
7194 </td>
7195
7196
7197
7198
7199
7200
7201 <td style="vertical-align: top;"><span style="font-style: italic;">single preci-</span><br style="font-style: italic;">
7202
7203
7204
7205
7206
7207
7208 <span style="font-style: italic;">sion for all</span><br style="font-style: italic;">
7209
7210
7211
7212
7213
7214
7215 <span style="font-style: italic;">output quan-</span><br style="font-style: italic;">
7216
7217
7218
7219
7220
7221
7222 <span style="font-style: italic;">tities</span><br>
7223
7224
7225
7226
7227
7228
7229 </td>
7230
7231
7232
7233
7234
7235
7236
7237      <td style="vertical-align: top;">Defines the accuracy of
7238the NetCDF output.<br>
7239
7240
7241
7242
7243
7244
7245 <br>
7246
7247
7248
7249
7250
7251
7252
7253By default, all NetCDF output data (see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
7254have single precision&nbsp; (4 byte) accuracy. Double precision (8
7255byte) can be choosen alternatively.<br>
7256
7257
7258
7259
7260
7261
7262
7263Accuracy for the different output data (cross sections, 3d-volume data,
7264spectra, etc.) can be set independently.<br>
7265
7266
7267
7268
7269
7270
7271 <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL4'</span>
7272(single precision) or <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL8'</span>
7273(double precision) are the two principally allowed values for <span style="font-weight: bold;">netcdf_precision</span>,
7274where the string <span style="font-style: italic;">'&lt;out&gt;'
7275      </span>can be chosen out of the following list:<br>
7276
7277
7278
7279
7280
7281
7282 <br>
7283
7284
7285
7286
7287
7288
7289
7290     
7291     
7292     
7293     
7294     
7295     
7296      <table style="text-align: left; width: 284px; height: 234px;" border="1" cellpadding="2" cellspacing="2">
7297
7298
7299
7300
7301
7302
7303 <tbody>
7304
7305
7306
7307
7308
7309
7310
7311          <tr>
7312
7313
7314
7315
7316
7317
7318 <td style="vertical-align: top;"><span style="font-style: italic;">'xy'</span><br>
7319
7320
7321
7322
7323
7324
7325 </td>
7326
7327
7328
7329
7330
7331
7332
7333            <td style="vertical-align: top;">horizontal cross section<br>
7334
7335
7336
7337
7338
7339
7340
7341            </td>
7342
7343
7344
7345
7346
7347
7348 </tr>
7349
7350
7351
7352
7353
7354
7355 <tr>
7356
7357
7358
7359
7360
7361
7362 <td style="vertical-align: top;"><span style="font-style: italic;">'xz'</span><br>
7363
7364
7365
7366
7367
7368
7369 </td>
7370
7371
7372
7373
7374
7375
7376
7377            <td style="vertical-align: top;">vertical (xz) cross
7378section<br>
7379
7380
7381
7382
7383
7384
7385 </td>
7386
7387
7388
7389
7390
7391
7392 </tr>
7393
7394
7395
7396
7397
7398
7399 <tr>
7400
7401
7402
7403
7404
7405
7406 <td style="vertical-align: top;"><span style="font-style: italic;">'yz'</span><br>
7407
7408
7409
7410
7411
7412
7413 </td>
7414
7415
7416
7417
7418
7419
7420
7421            <td style="vertical-align: top;">vertical (yz) cross
7422section<br>
7423
7424
7425
7426
7427
7428
7429 </td>
7430
7431
7432
7433
7434
7435
7436 </tr>
7437
7438
7439
7440
7441
7442
7443 <tr>
7444
7445
7446
7447
7448
7449
7450 <td style="vertical-align: top;"><span style="font-style: italic;">'2d'</span><br>
7451
7452
7453
7454
7455
7456
7457 </td>
7458
7459
7460
7461
7462
7463
7464
7465            <td style="vertical-align: top;">all cross sections<br>
7466
7467
7468
7469
7470
7471
7472
7473            </td>
7474
7475
7476
7477
7478
7479
7480 </tr>
7481
7482
7483
7484
7485
7486
7487 <tr>
7488
7489
7490
7491
7492
7493
7494 <td style="vertical-align: top;"><span style="font-style: italic;">'3d'</span><br>
7495
7496
7497
7498
7499
7500
7501 </td>
7502
7503
7504
7505
7506
7507
7508
7509            <td style="vertical-align: top;">volume data<br>
7510
7511
7512
7513
7514
7515
7516 </td>
7517
7518
7519
7520
7521
7522
7523
7524          </tr>
7525
7526
7527
7528
7529
7530
7531 <tr>
7532
7533
7534
7535
7536
7537
7538 <td style="vertical-align: top;"><span style="font-style: italic;">'pr'</span><br>
7539
7540
7541
7542
7543
7544
7545 </td>
7546
7547
7548
7549
7550
7551
7552
7553            <td style="vertical-align: top;">vertical profiles<br>
7554
7555
7556
7557
7558
7559
7560
7561            </td>
7562
7563
7564
7565
7566
7567
7568 </tr>
7569
7570
7571
7572
7573
7574
7575 <tr>
7576
7577
7578
7579
7580
7581
7582 <td style="vertical-align: top;"><span style="font-style: italic;">'ts'</span><br>
7583
7584
7585
7586
7587
7588
7589 </td>
7590
7591
7592
7593
7594
7595
7596
7597            <td style="vertical-align: top;">time series, particle
7598time series<br>
7599
7600
7601
7602
7603
7604
7605 </td>
7606
7607
7608
7609
7610
7611
7612 </tr>
7613
7614
7615
7616
7617
7618
7619 <tr>
7620
7621
7622
7623
7624
7625
7626 <td style="vertical-align: top;"><span style="font-style: italic;">'sp'</span><br>
7627
7628
7629
7630
7631
7632
7633 </td>
7634
7635
7636
7637
7638
7639
7640
7641            <td style="vertical-align: top;">spectra<br>
7642
7643
7644
7645
7646
7647
7648 </td>
7649
7650
7651
7652
7653
7654
7655
7656          </tr>
7657
7658
7659
7660
7661
7662
7663 <tr>
7664
7665
7666
7667
7668
7669
7670 <td style="vertical-align: top;"><span style="font-style: italic;">'prt'</span><br>
7671
7672
7673
7674
7675
7676
7677 </td>
7678
7679
7680
7681
7682
7683
7684
7685            <td style="vertical-align: top;">particles<br>
7686
7687
7688
7689
7690
7691
7692 </td>
7693
7694
7695
7696
7697
7698
7699
7700          </tr>
7701
7702
7703
7704
7705
7706
7707 <tr>
7708
7709
7710
7711
7712
7713
7714 <td style="vertical-align: top;"><span style="font-style: italic;">'all'</span><br>
7715
7716
7717
7718
7719
7720
7721 </td>
7722
7723
7724
7725
7726
7727
7728
7729            <td style="vertical-align: top;">all output quantities<br>
7730
7731
7732
7733
7734
7735
7736
7737            </td>
7738
7739
7740
7741
7742
7743
7744 </tr>
7745
7746
7747
7748
7749
7750
7751 
7752       
7753       
7754       
7755       
7756       
7757       
7758        </tbody> 
7759     
7760     
7761     
7762     
7763     
7764     
7765      </table>
7766
7767
7768
7769
7770
7771
7772 <br>
7773
7774
7775
7776
7777
7778
7779 <span style="font-weight: bold;">Example:</span><br>
7780
7781
7782
7783
7784
7785
7786
7787If all cross section data and the particle data shall be output in
7788double 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>
7789has to be assigned.<br>
7790
7791
7792
7793
7794
7795
7796 </td>
7797
7798
7799
7800
7801
7802
7803 </tr>
7804
7805
7806
7807
7808
7809
7810
7811    <tr>
7812
7813
7814
7815
7816
7817
7818 <td style="vertical-align: top;"> 
7819     
7820     
7821     
7822     
7823     
7824     
7825      <p><a name="npex"></a><b>npex</b></p>
7826
7827
7828
7829
7830
7831
7832 </td>
7833
7834
7835
7836
7837
7838
7839
7840      <td style="vertical-align: top;">I</td>
7841
7842
7843
7844
7845
7846
7847 <td style="vertical-align: top;"><br>
7848
7849
7850
7851
7852
7853
7854 </td>
7855
7856
7857
7858
7859
7860
7861 <td style="vertical-align: top;"> 
7862     
7863     
7864     
7865     
7866     
7867     
7868      <p>Number of processors
7869along x-direction of the virtual
7870processor
7871net.&nbsp; </p>
7872
7873
7874
7875
7876
7877
7878 
7879     
7880     
7881     
7882     
7883     
7884     
7885      <p>For parallel runs, the total
7886number of processors to be used
7887is given by
7888the <span style="font-weight: bold;">mrun</span>
7889option <a href="http://www.muk.uni-hannover.de/software/mrun_beschreibung.html#Opt-X">-X</a>.
7890By default, depending on the type of the parallel computer, PALM
7891generates a 1d processor
7892net (domain decomposition along x, <span style="font-weight: bold;">npey</span>
7893= <span style="font-style: italic;">1</span>) or a
78942d-net (this is
7895favored on machines with fast communication network). In case of a
78962d-net, it is tried to make it more or less square-shaped. If, for
7897example, 16 processors are assigned (-X 16), a 4 * 4 processor net is
7898generated (<span style="font-weight: bold;">npex</span>
7899= <span style="font-style: italic;">4</span>, <span style="font-weight: bold;">npey</span>
7900= <span style="font-style: italic;">4</span>).
7901This choice is optimal for square total domains (<a href="#nx">nx</a>
7902= <a href="#ny">ny</a>),
7903since then the number of ghost points at the lateral boundarys of
7904the subdomains is minimal. If <span style="font-weight: bold;">nx</span>
7905nd <span style="font-weight: bold;">ny</span>
7906differ extremely, the
7907processor 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>
7908
7909
7910
7911
7912
7913
7914
7915     
7916     
7917     
7918     
7919     
7920     
7921      <p><b>Important:</b> The value of <span style="font-weight: bold;">npex</span> * <span style="font-weight: bold;">npey</span> must exactly
7922correspond to the
7923value assigned by the <span style="font-weight: bold;">mrun</span>-option
7924      <tt>-X</tt>.
7925Otherwise the model run will abort with a corresponding error
7926message.&nbsp; <br>
7927
7928
7929
7930
7931
7932
7933
7934Additionally, the specification of <span style="font-weight: bold;">npex</span>
7935and <span style="font-weight: bold;">npey</span>
7936may of course
7937override the default setting for the domain decomposition (1d or 2d)
7938which may have a significant (negative) effect on the code performance.
7939      </p>
7940
7941
7942
7943
7944
7945
7946 </td>
7947
7948
7949
7950
7951
7952
7953 </tr>
7954
7955
7956
7957
7958
7959
7960 <tr>
7961
7962
7963
7964
7965
7966
7967 <td style="vertical-align: top;"> 
7968     
7969     
7970     
7971     
7972     
7973     
7974      <p><a name="npey"></a><b>npey</b></p>
7975
7976
7977
7978
7979
7980
7981
7982      </td>
7983
7984
7985
7986
7987
7988
7989 <td style="vertical-align: top;">I</td>
7990
7991
7992
7993
7994
7995
7996
7997      <td style="vertical-align: top;"><br>
7998
7999
8000
8001
8002
8003
8004 </td>
8005
8006
8007
8008
8009
8010
8011 <td style="vertical-align: top;"> 
8012     
8013     
8014     
8015     
8016     
8017     
8018      <p>Number of processors
8019along y-direction of the virtual
8020processor
8021net.&nbsp; </p>
8022
8023
8024
8025
8026
8027
8028 
8029     
8030     
8031     
8032     
8033     
8034     
8035      <p>For further information see <a href="#npex">npex</a>.</p>
8036
8037
8038
8039
8040
8041
8042 </td>
8043
8044
8045
8046
8047
8048
8049 </tr>
8050
8051
8052
8053
8054
8055
8056
8057    <tr>
8058
8059
8060
8061
8062
8063
8064 <td style="vertical-align: top;"> 
8065     
8066     
8067     
8068     
8069     
8070     
8071      <p><a name="nsor_ini"></a><b>nsor_ini</b></p>
8072
8073
8074
8075
8076
8077
8078
8079      </td>
8080
8081
8082
8083
8084
8085
8086 <td style="vertical-align: top;">I</td>
8087
8088
8089
8090
8091
8092
8093
8094      <td style="vertical-align: top;"><i>100</i></td>
8095
8096
8097
8098
8099
8100
8101
8102      <td style="vertical-align: top;"> 
8103     
8104     
8105     
8106     
8107     
8108     
8109      <p>Initial number
8110of iterations with the SOR algorithm.&nbsp; </p>
8111
8112
8113
8114
8115
8116
8117 
8118     
8119     
8120     
8121     
8122     
8123     
8124      <p>This
8125parameter is only effective if the SOR algorithm was
8126selected as the pressure solver scheme (<a href="chapter_4.2.html#psolver">psolver</a>
8127= <span style="font-style: italic;">'sor'</span>)
8128and specifies the
8129number of initial iterations of the SOR
8130scheme (at t = 0). The number of subsequent iterations at the following
8131timesteps is determined
8132with the parameter <a href="#nsor">nsor</a>.
8133Usually <b>nsor</b> &lt; <b>nsor_ini</b>,
8134since in each case
8135subsequent calls to <a href="chapter_4.2.html#psolver">psolver</a>
8136use the solution of the previous call as initial value. Suitable
8137test runs should determine whether sufficient convergence of the
8138solution is obtained with the default value and if necessary the value
8139of <b>nsor_ini</b> should be changed.</p>
8140
8141
8142
8143
8144
8145
8146 </td>
8147
8148
8149
8150
8151
8152
8153
8154    </tr>
8155
8156
8157
8158
8159
8160
8161 <tr>
8162
8163
8164
8165
8166
8167
8168 <td style="vertical-align: top;">
8169     
8170     
8171     
8172     
8173     
8174     
8175      <p><a name="nx"></a><b>nx</b></p>
8176
8177
8178
8179
8180
8181
8182
8183      </td>
8184
8185
8186
8187
8188
8189
8190 <td style="vertical-align: top;">I</td>
8191
8192
8193
8194
8195
8196
8197
8198      <td style="vertical-align: top;"><br>
8199
8200
8201
8202
8203
8204
8205 </td>
8206
8207
8208
8209
8210
8211
8212 <td style="vertical-align: top;"> 
8213     
8214     
8215     
8216     
8217     
8218     
8219      <p>Number of grid
8220points in x-direction.&nbsp; </p>
8221
8222
8223
8224
8225
8226
8227 
8228     
8229     
8230     
8231     
8232     
8233     
8234      <p>A value for this
8235parameter must be assigned. Since the lower
8236array bound in PALM
8237starts with i = 0, the actual number of grid points is equal to <b>nx+1</b>.
8238In case of cyclic boundary conditions along x, the domain size is (<b>nx+1</b>)*
8239      <a href="#dx">dx</a>.</p>
8240
8241
8242
8243
8244
8245
8246 
8247     
8248     
8249     
8250     
8251     
8252     
8253      <p>For
8254parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8255= <span style="font-style: italic;">'strict'</span>,
8256      <b>nx+1</b> must
8257be an integral multiple
8258of the processor numbers (see <a href="#npex">npex</a>
8259and <a href="#npey">npey</a>)
8260along x- as well as along y-direction (due to data
8261transposition restrictions).</p>
8262
8263
8264
8265
8266
8267
8268     
8269     
8270     
8271     
8272     
8273     
8274      <p>For <a href="chapter_3.8.html">coupled runs</a> this parameter must be&nbsp;equal in both parameter files <a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2"><span style="font-family: mon;"></span>PARIN</font></a>
8275and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8276
8277
8278
8279
8280
8281
8282 </td>
8283
8284
8285
8286
8287
8288
8289 </tr>
8290
8291
8292
8293
8294
8295
8296 <tr>
8297
8298
8299
8300
8301
8302
8303
8304      <td style="vertical-align: top;"> 
8305     
8306     
8307     
8308     
8309     
8310     
8311      <p><a name="ny"></a><b>ny</b></p>
8312
8313
8314
8315
8316
8317
8318
8319      </td>
8320
8321
8322
8323
8324
8325
8326 <td style="vertical-align: top;">I</td>
8327
8328
8329
8330
8331
8332
8333
8334      <td style="vertical-align: top;"><br>
8335
8336
8337
8338
8339
8340
8341 </td>
8342
8343
8344
8345
8346
8347
8348 <td style="vertical-align: top;"> 
8349     
8350     
8351     
8352     
8353     
8354     
8355      <p>Number of grid
8356points in y-direction.&nbsp; </p>
8357
8358
8359
8360
8361
8362
8363 
8364     
8365     
8366     
8367     
8368     
8369     
8370      <p>A value for this
8371parameter must be assigned. Since the lower
8372array bound in PALM starts with j = 0, the actual number of grid points
8373is equal to <b>ny+1</b>. In case of cyclic boundary
8374conditions along
8375y, the domain size is (<b>ny+1</b>) * <a href="#dy">dy</a>.</p>
8376
8377
8378
8379
8380
8381
8382
8383     
8384     
8385     
8386     
8387     
8388     
8389      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8390= <span style="font-style: italic;">'strict'</span>,
8391      <b>ny+1</b> must
8392be an integral multiple
8393of the processor numbers (see <a href="#npex">npex</a>
8394and <a href="#npey">npey</a>)&nbsp;
8395along y- as well as along x-direction (due to data
8396transposition restrictions).</p>
8397
8398
8399
8400
8401
8402
8403     
8404     
8405     
8406     
8407     
8408     
8409      <p>For <a href="chapter_3.8.html">coupled runs</a> this parameter must be&nbsp;equal in both parameter files <a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2"><span style="font-family: mon;"></span>PARIN</font></a>
8410and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8411
8412
8413
8414
8415
8416
8417 </td>
8418
8419
8420
8421
8422
8423
8424 </tr>
8425
8426
8427
8428
8429
8430
8431 <tr>
8432
8433
8434
8435
8436
8437
8438
8439      <td style="vertical-align: top;"> 
8440     
8441     
8442     
8443     
8444     
8445     
8446      <p><a name="nz"></a><b>nz</b></p>
8447
8448
8449
8450
8451
8452
8453
8454      </td>
8455
8456
8457
8458
8459
8460
8461 <td style="vertical-align: top;">I</td>
8462
8463
8464
8465
8466
8467
8468
8469      <td style="vertical-align: top;"><br>
8470
8471
8472
8473
8474
8475
8476 </td>
8477
8478
8479
8480
8481
8482
8483 <td style="vertical-align: top;"> 
8484     
8485     
8486     
8487     
8488     
8489     
8490      <p>Number of grid
8491points in z-direction.&nbsp; </p>
8492
8493
8494
8495
8496
8497
8498 
8499     
8500     
8501     
8502     
8503     
8504     
8505      <p>A value for this
8506parameter must be assigned. Since the lower
8507array bound in PALM
8508starts with k = 0 and since one additional grid point is added at the
8509top boundary (k = <b>nz+1</b>), the actual number of grid
8510points is <b>nz+2</b>.
8511However, the prognostic equations are only solved up to <b>nz</b>
8512(u,
8513v)
8514or up to <b>nz-1</b> (w, scalar quantities). The top
8515boundary for u
8516and v is at k = <b>nz+1</b> (u, v) while at k = <b>nz</b>
8517for all
8518other quantities.&nbsp; </p>
8519
8520
8521
8522
8523
8524
8525 
8526     
8527     
8528     
8529     
8530     
8531     
8532      <p>For parallel
8533runs,&nbsp; in case of <a href="#grid_matching">grid_matching</a>
8534= <span style="font-style: italic;">'strict'</span>,
8535      <b>nz</b> must
8536be an integral multiple of
8537the number of processors in x-direction (due to data transposition
8538restrictions).</p>
8539
8540
8541
8542
8543
8544
8545 </td>
8546
8547
8548
8549
8550
8551
8552 </tr>
8553
8554
8555
8556
8557
8558
8559 <tr>
8560
8561
8562
8563
8564
8565
8566      <td style="vertical-align: top;"><a name="ocean"></a><span style="font-weight: bold;">ocean</span></td>
8567
8568
8569
8570
8571
8572
8573      <td style="vertical-align: top;">L</td>
8574
8575
8576
8577
8578
8579
8580      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
8581
8582
8583
8584
8585
8586
8587      <td style="vertical-align: top;">Parameter to switch on&nbsp;ocean runs.<br>
8588
8589
8590
8591
8592
8593
8594      <br>
8595
8596
8597
8598
8599
8600
8601By default PALM is configured to simulate&nbsp;atmospheric flows. However, starting from version 3.3, <span style="font-weight: bold;">ocean</span> = <span style="font-style: italic;">.T.</span> allows&nbsp;simulation of ocean turbulent flows. Setting this switch has several effects:<br>
8602
8603
8604
8605
8606
8607
8608      <br>
8609
8610
8611
8612
8613
8614
8615     
8616     
8617     
8618     
8619     
8620     
8621      <ul>
8622
8623
8624
8625
8626
8627
8628        <li>An additional prognostic equation for salinity is solved.</li>
8629
8630
8631
8632
8633
8634
8635        <li>Potential temperature in buoyancy and stability-related terms is replaced by potential density.</li>
8636
8637
8638
8639
8640
8641
8642        <li>Potential
8643density is calculated from the equation of state for seawater after
8644each timestep, using the algorithm proposed by Jackett et al. (2006, J.
8645Atmos. Oceanic Technol., <span style="font-weight: bold;">23</span>, 1709-1728).<br>
8646
8647
8648
8649
8650
8651
8652So far, only the initial hydrostatic pressure is entered into this equation.</li>
8653
8654
8655
8656
8657
8658
8659        <li>z=0 (sea surface) is assumed at the model top (vertical grid index <span style="font-family: Courier New,Courier,monospace;">k=nzt</span> on the w-grid), with negative values of z indicating the depth.</li>
8660
8661
8662
8663
8664
8665
8666        <li>Initial profiles are constructed (e.g. from <a href="#pt_vertical_gradient">pt_vertical_gradient</a> / <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>) starting from the sea surface, using surface values&nbsp;given by <a href="#pt_surface">pt_surface</a>, <a href="#sa_surface">sa_surface</a>, <a href="#ug_surface">ug_surface</a>, and <a href="#vg_surface">vg_surface</a>.</li>
8667
8668
8669
8670
8671
8672
8673        <li>Zero salinity flux is used as default boundary condition at the bottom of the sea.</li>
8674
8675
8676
8677
8678
8679
8680        <li>If switched on, random perturbations are by default imposed to the upper model domain from zu(nzt*2/3) to zu(nzt-3).</li>
8681
8682
8683
8684
8685
8686
8687     
8688     
8689     
8690     
8691     
8692     
8693      </ul>
8694
8695
8696
8697
8698
8699
8700      <br>
8701
8702
8703
8704
8705
8706
8707Relevant parameters to be exclusively used for steering ocean runs are <a href="#bc_sa_t">bc_sa_t</a>, <a href="#bottom_salinityflux">bottom_salinityflux</a>, <a href="#sa_surface">sa_surface</a>, <a href="#sa_vertical_gradient">sa_vertical_gradient</a>, <a href="#sa_vertical_gradient_level">sa_vertical_gradient_level</a>, and <a href="#top_salinityflux">top_salinityflux</a>.<br>
8708
8709
8710
8711
8712
8713
8714      <br>
8715
8716
8717
8718
8719
8720
8721Section <a href="chapter_4.2.2.html">4.4.2</a> gives an example for appropriate settings of these and other parameters neccessary for ocean runs.<br>
8722
8723
8724
8725
8726
8727
8728      <br>
8729
8730
8731
8732
8733
8734
8735      <span style="font-weight: bold;">ocean</span> = <span style="font-style: italic;">.T.</span> does not allow settings of <a href="#timestep_scheme">timestep_scheme</a> = <span style="font-style: italic;">'leapfrog'</span> or <span style="font-style: italic;">'leapfrog+euler'</span> as well as <a href="#scalar_advec">scalar_advec</a> = <span style="font-style: italic;">'ups-scheme'</span>.<span style="font-weight: bold;"></span><br>
8736
8737
8738
8739      </td>
8740
8741
8742
8743
8744
8745
8746    </tr>
8747
8748
8749
8750
8751
8752
8753    <tr>
8754
8755
8756
8757
8758
8759
8760 <td style="vertical-align: top;"> 
8761     
8762     
8763     
8764     
8765     
8766     
8767      <p><a name="omega"></a><b>omega</b></p>
8768
8769
8770
8771
8772
8773
8774
8775      </td>
8776
8777
8778
8779
8780
8781
8782 <td style="vertical-align: top;">R</td>
8783
8784
8785
8786
8787
8788
8789
8790      <td style="vertical-align: top;"><i>7.29212E-5</i></td>
8791
8792
8793
8794
8795
8796
8797
8798      <td style="vertical-align: top;"> 
8799     
8800     
8801     
8802     
8803     
8804     
8805      <p>Angular
8806velocity of the rotating system (in rad s<sup>-1</sup>).&nbsp;
8807      </p>
8808
8809
8810
8811
8812
8813
8814 
8815     
8816     
8817     
8818     
8819     
8820     
8821      <p>The angular velocity of the earth is set by
8822default. The
8823values
8824of the Coriolis parameters are calculated as:&nbsp; </p>
8825
8826
8827
8828
8829
8830
8831 
8832     
8833     
8834     
8835     
8836     
8837     
8838      <ul>
8839
8840
8841
8842
8843
8844
8845
8846       
8847       
8848       
8849       
8850       
8851       
8852        <p>f = 2.0 * <b>omega</b> * sin(<a href="#phi">phi</a>)&nbsp;
8853        <br>
8854
8855
8856
8857
8858
8859
8860f* = 2.0 * <b>omega</b> * cos(<a href="#phi">phi</a>)</p>
8861
8862
8863
8864
8865
8866
8867
8868     
8869     
8870     
8871     
8872     
8873     
8874      </ul>
8875
8876
8877
8878
8879
8880
8881 </td>
8882
8883
8884
8885
8886
8887
8888 </tr>
8889
8890
8891
8892
8893
8894
8895 <tr>
8896
8897
8898
8899
8900
8901
8902 <td style="vertical-align: top;"> 
8903     
8904     
8905     
8906     
8907     
8908     
8909      <p><a name="outflow_damping_width"></a><b>outflow_damping_width</b></p>
8910
8911
8912
8913
8914
8915
8916
8917      </td>
8918
8919
8920
8921
8922
8923
8924 <td style="vertical-align: top;">I</td>
8925
8926
8927
8928
8929
8930
8931
8932      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(20,
8933nx/2</span> or <span style="font-style: italic;">ny/2)</span></td>
8934
8935
8936
8937
8938
8939
8940
8941      <td style="vertical-align: top;">Width of
8942the damping range in the vicinity of the outflow (gridpoints).<br>
8943
8944
8945
8946
8947
8948
8949
8950      <br>
8951
8952
8953
8954
8955
8956
8957
8958When using non-cyclic lateral boundaries (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
8959or <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
8960a smoothing has to be applied to the
8961velocity field in the vicinity of the outflow in order to suppress any
8962reflections of outgoing disturbances. This parameter controlls the
8963horizontal range to which the smoothing is applied. The range is given
8964in gridpoints counted from the respective outflow boundary. For further
8965details about the smoothing see parameter <a href="chapter_4.1.html#km_damp_max">km_damp_max</a>,
8966which defines the magnitude of the damping.</td>
8967
8968
8969
8970
8971
8972
8973 </tr>
8974
8975
8976
8977
8978
8979
8980
8981    <tr>
8982
8983
8984
8985
8986
8987
8988 <td style="vertical-align: top;"> 
8989     
8990     
8991     
8992     
8993     
8994     
8995      <p><a name="overshoot_limit_e"></a><b>overshoot_limit_e</b></p>
8996
8997
8998
8999
9000
9001
9002
9003      </td>
9004
9005
9006
9007
9008
9009
9010 <td style="vertical-align: top;">R</td>
9011
9012
9013
9014
9015
9016
9017
9018      <td style="vertical-align: top;"><i>0.0</i></td>
9019
9020
9021
9022
9023
9024
9025
9026      <td style="vertical-align: top;"> 
9027     
9028     
9029     
9030     
9031     
9032     
9033      <p>Allowed limit
9034for the overshooting of subgrid-scale TKE in
9035case that the upstream-spline scheme is switched on (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
9036      </p>
9037
9038
9039
9040
9041
9042
9043 
9044     
9045     
9046     
9047     
9048     
9049     
9050      <p>By deafult, if cut-off of overshoots is switched
9051on for the
9052upstream-spline scheme (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>),
9053no overshoots are permitted at all. If <b>overshoot_limit_e</b>
9054is given a non-zero value, overshoots with the respective
9055amplitude (both upward and downward) are allowed.&nbsp; </p>
9056
9057
9058
9059
9060
9061
9062
9063     
9064     
9065     
9066     
9067     
9068     
9069      <p>Only positive values are allowed for <b>overshoot_limit_e</b>.</p>
9070
9071
9072
9073
9074
9075
9076
9077      </td>
9078
9079
9080
9081
9082
9083
9084 </tr>
9085
9086
9087
9088
9089
9090
9091 <tr>
9092
9093
9094
9095
9096
9097
9098 <td style="vertical-align: top;"> 
9099     
9100     
9101     
9102     
9103     
9104     
9105      <p><a name="overshoot_limit_pt"></a><b>overshoot_limit_pt</b></p>
9106
9107
9108
9109
9110
9111
9112
9113      </td>
9114
9115
9116
9117
9118
9119
9120 <td style="vertical-align: top;">R</td>
9121
9122
9123
9124
9125
9126
9127
9128      <td style="vertical-align: top;"><i>0.0</i></td>
9129
9130
9131
9132
9133
9134
9135
9136      <td style="vertical-align: top;"> 
9137     
9138     
9139     
9140     
9141     
9142     
9143      <p>Allowed limit
9144for the overshooting of potential temperature in
9145case that the upstream-spline scheme is switched on (in K).&nbsp; </p>
9146
9147
9148
9149
9150
9151
9152
9153     
9154     
9155     
9156     
9157     
9158     
9159      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9160      </p>
9161
9162
9163
9164
9165
9166
9167 
9168     
9169     
9170     
9171     
9172     
9173     
9174      <p>Only positive values are allowed for <b>overshoot_limit_pt</b>.</p>
9175
9176
9177
9178
9179
9180
9181
9182      </td>
9183
9184
9185
9186
9187
9188
9189 </tr>
9190
9191
9192
9193
9194
9195
9196 <tr>
9197
9198
9199
9200
9201
9202
9203 <td style="vertical-align: top;"> 
9204     
9205     
9206     
9207     
9208     
9209     
9210      <p><a name="overshoot_limit_u"></a><b>overshoot_limit_u</b></p>
9211
9212
9213
9214
9215
9216
9217
9218      </td>
9219
9220
9221
9222
9223
9224
9225 <td style="vertical-align: top;">R</td>
9226
9227
9228
9229
9230
9231
9232
9233      <td style="vertical-align: top;"><i>0.0</i></td>
9234
9235
9236
9237
9238
9239
9240
9241      <td style="vertical-align: top;">Allowed limit for the
9242overshooting of
9243the u-component of velocity in case that the upstream-spline scheme is
9244switched on (in m/s).
9245     
9246     
9247     
9248     
9249     
9250     
9251      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9252      </p>
9253
9254
9255
9256
9257
9258
9259 
9260     
9261     
9262     
9263     
9264     
9265     
9266      <p>Only positive values are allowed for <b>overshoot_limit_u</b>.</p>
9267
9268
9269
9270
9271
9272
9273
9274      </td>
9275
9276
9277
9278
9279
9280
9281 </tr>
9282
9283
9284
9285
9286
9287
9288 <tr>
9289
9290
9291
9292
9293
9294
9295 <td style="vertical-align: top;"> 
9296     
9297     
9298     
9299     
9300     
9301     
9302      <p><a name="overshoot_limit_v"></a><b>overshoot_limit_v</b></p>
9303
9304
9305
9306
9307
9308
9309
9310      </td>
9311
9312
9313
9314
9315
9316
9317 <td style="vertical-align: top;">R</td>
9318
9319
9320
9321
9322
9323
9324
9325      <td style="vertical-align: top;"><i>0.0</i></td>
9326
9327
9328
9329
9330
9331
9332
9333      <td style="vertical-align: top;"> 
9334     
9335     
9336     
9337     
9338     
9339     
9340      <p>Allowed limit
9341for the overshooting of the v-component of
9342velocity in case that the upstream-spline scheme is switched on
9343(in m/s).&nbsp; </p>
9344
9345
9346
9347
9348
9349
9350 
9351     
9352     
9353     
9354     
9355     
9356     
9357      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9358      </p>
9359
9360
9361
9362
9363
9364
9365 
9366     
9367     
9368     
9369     
9370     
9371     
9372      <p>Only positive values are allowed for <b>overshoot_limit_v</b>.</p>
9373
9374
9375
9376
9377
9378
9379
9380      </td>
9381
9382
9383
9384
9385
9386
9387 </tr>
9388
9389
9390
9391
9392
9393
9394 <tr>
9395
9396
9397
9398
9399
9400
9401 <td style="vertical-align: top;"> 
9402     
9403     
9404     
9405     
9406     
9407     
9408      <p><a name="overshoot_limit_w"></a><b>overshoot_limit_w</b></p>
9409
9410
9411
9412
9413
9414
9415
9416      </td>
9417
9418
9419
9420
9421
9422
9423 <td style="vertical-align: top;">R</td>
9424
9425
9426
9427
9428
9429
9430
9431      <td style="vertical-align: top;"><i>0.0</i></td>
9432
9433
9434
9435
9436
9437
9438
9439      <td style="vertical-align: top;"> 
9440     
9441     
9442     
9443     
9444     
9445     
9446      <p>Allowed limit
9447for the overshooting of the w-component of
9448velocity in case that the upstream-spline scheme is switched on
9449(in m/s).&nbsp; </p>
9450
9451
9452
9453
9454
9455
9456 
9457     
9458     
9459     
9460     
9461     
9462     
9463      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9464      </p>
9465
9466
9467
9468
9469
9470
9471 
9472     
9473     
9474     
9475     
9476     
9477     
9478      <p>Only positive values are permitted for <b>overshoot_limit_w</b>.</p>
9479
9480
9481
9482
9483
9484
9485
9486      </td>
9487
9488
9489
9490
9491
9492
9493 </tr>
9494
9495
9496
9497
9498
9499
9500 <tr>
9501
9502
9503
9504
9505
9506
9507 <td style="vertical-align: top;"> 
9508     
9509     
9510     
9511     
9512     
9513     
9514      <p><a name="passive_scalar"></a><b>passive_scalar</b></p>
9515
9516
9517
9518
9519
9520
9521
9522      </td>
9523
9524
9525
9526
9527
9528
9529 <td style="vertical-align: top;">L</td>
9530
9531
9532
9533
9534
9535
9536
9537      <td style="vertical-align: top;"><i>.F.</i></td>
9538
9539
9540
9541
9542
9543
9544
9545      <td style="vertical-align: top;"> 
9546     
9547     
9548     
9549     
9550     
9551     
9552      <p>Parameter to
9553switch on the prognostic equation for a passive
9554scalar. <br>
9555
9556
9557
9558
9559
9560
9561 </p>
9562
9563
9564
9565
9566
9567
9568 
9569     
9570     
9571     
9572     
9573     
9574     
9575      <p>The initial vertical profile
9576of s can be set via parameters <a href="#s_surface">s_surface</a>,
9577      <a href="#s_vertical_gradient">s_vertical_gradient</a>
9578and&nbsp; <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.
9579Boundary conditions can be set via <a href="#s_surface_initial_change">s_surface_initial_change</a>
9580and <a href="#surface_scalarflux">surface_scalarflux</a>.&nbsp;
9581      </p>
9582
9583
9584
9585
9586
9587
9588 
9589     
9590     
9591     
9592     
9593     
9594     
9595      <p><b>Note:</b> <br>
9596
9597
9598
9599
9600
9601
9602
9603With <span style="font-weight: bold;">passive_scalar</span>
9604switched
9605on, the simultaneous use of humidity (see&nbsp;<a href="#humidity">humidity</a>)
9606is impossible.</p>
9607
9608
9609
9610
9611
9612
9613 </td>
9614
9615
9616
9617
9618
9619
9620 </tr>
9621
9622
9623
9624
9625
9626
9627 <tr>
9628
9629      <td style="vertical-align: top;"><a name="pch_index"></a><span style="font-weight: bold;">pch_index</span></td>
9630
9631      <td style="vertical-align: top;">I</td>
9632
9633      <td style="vertical-align: top;"><span style="font-style: italic;">0</span></td>
9634
9635      <td style="vertical-align: top;">Grid point index (scalar) of the upper boundary of the plant canopy layer.<br>
9636
9637      <br>
9638
9639Above <span style="font-weight: bold;">pch_index</span> the arrays of leaf area density and drag_coeffient are automatically set to zero in case of <a href="#plant_canopy">plant_canopy</a> = .T.. Up to <span style="font-weight: bold;">pch_index</span> a leaf area density profile can be prescribed by using the parameters <a href="#lad_surface">lad_surface</a>, <a href="#lad_vertical_gradient">lad_vertical_gradient</a> and <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>.</td>
9640
9641    </tr>
9642
9643    <tr>
9644
9645
9646
9647
9648
9649
9650 <td style="vertical-align: top;"> 
9651     
9652     
9653     
9654     
9655     
9656     
9657      <p><a name="phi"></a><b>phi</b></p>
9658
9659
9660
9661
9662
9663
9664
9665      </td>
9666
9667
9668
9669
9670
9671
9672 <td style="vertical-align: top;">R</td>
9673
9674
9675
9676
9677
9678
9679
9680      <td style="vertical-align: top;"><i>55.0</i></td>
9681
9682
9683
9684
9685
9686
9687
9688      <td style="vertical-align: top;"> 
9689     
9690     
9691     
9692     
9693     
9694     
9695      <p>Geographical
9696latitude (in degrees).&nbsp; </p>
9697
9698
9699
9700
9701
9702
9703 
9704     
9705     
9706     
9707     
9708     
9709     
9710      <p>The value of
9711this parameter determines the value of the
9712Coriolis parameters f and f*, provided that the angular velocity (see <a href="#omega">omega</a>)
9713is non-zero.</p>
9714
9715
9716
9717
9718
9719
9720 </td>
9721
9722
9723
9724
9725
9726
9727 </tr>
9728
9729
9730
9731
9732
9733
9734 <tr>
9735
9736      <td style="vertical-align: top;"><a name="plant_canopy"></a><span style="font-weight: bold;">plant_canopy</span></td>
9737
9738      <td style="vertical-align: top;">L</td>
9739
9740      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9741
9742      <td style="vertical-align: top;">Switch for the plant_canopy_model.<br>
9743
9744      <br>
9745
9746If <span style="font-weight: bold;">plant_canopy</span> is set <span style="font-style: italic;">.T.</span>, the plant canopy model of Watanabe (2004, BLM 112, 307-341) is used. <br>
9747
9748The
9749impact of a plant canopy on a turbulent flow is considered by an
9750additional drag term in the momentum equations and an additional sink
9751term in the prognostic equation for the subgrid-scale TKE. These
9752additional terms are dependent on the leaf drag coefficient (see <a href="#drag_coefficient">drag_coefficient</a>) and the leaf area density (see <a href="#lad_surface">lad_surface</a>, <a href="#lad_vertical_gradient">lad_vertical_gradient</a>, <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>). <br>
9753
9754By default, a horizontally homogeneous plant canopy is prescribed, if&nbsp; <span style="font-weight: bold;">plant_canopy</span> is set <span style="font-style: italic;">.T.</span>. However, the user can define other types of plant canopies (see <a href="#canopy_mode">canopy_mode</a>).<br>
9755
9756      <br>
9757
9758      <span style="font-weight: bold;">plant_canopy</span> = <span style="font-style: italic;">.T. </span>is only allowed together with a non-zero <a href="#drag_coefficient">drag_coefficient</a>.</td>
9759
9760    </tr>
9761
9762    <tr>
9763
9764
9765
9766
9767
9768
9769 <td style="vertical-align: top;"> 
9770     
9771     
9772     
9773     
9774     
9775     
9776      <p><a name="prandtl_layer"></a><b>prandtl_layer</b></p>
9777
9778
9779
9780
9781
9782
9783
9784      </td>
9785
9786
9787
9788
9789
9790
9791 <td style="vertical-align: top;">L</td>
9792
9793
9794
9795
9796
9797
9798
9799      <td style="vertical-align: top;"><i>.T.</i></td>
9800
9801
9802
9803
9804
9805
9806
9807      <td style="vertical-align: top;"> 
9808     
9809     
9810     
9811     
9812     
9813     
9814      <p>Parameter to
9815switch on a Prandtl layer.&nbsp; </p>
9816
9817
9818
9819
9820
9821
9822 
9823     
9824     
9825     
9826     
9827     
9828     
9829      <p>By default,
9830a Prandtl layer is switched on at the bottom
9831boundary between z = 0 and z = 0.5 * <a href="#dz">dz</a>
9832(the first computational grid point above ground for u, v and the
9833scalar quantities).
9834In this case, at the bottom boundary, free-slip conditions for u and v
9835(see <a href="#bc_uv_b">bc_uv_b</a>)
9836are not allowed. Likewise, laminar
9837simulations with constant eddy diffusivities (<a href="#km_constant">km_constant</a>)
9838are forbidden.&nbsp; </p>
9839
9840
9841
9842
9843
9844
9845 
9846     
9847     
9848     
9849     
9850     
9851     
9852      <p>With Prandtl-layer
9853switched off, the TKE boundary condition <a href="#bc_e_b">bc_e_b</a>
9854= '<i>(u*)**2+neumann'</i> must not be used and is
9855automatically
9856changed to <i>'neumann'</i> if necessary.&nbsp; Also,
9857the pressure
9858boundary condition <a href="#bc_p_b">bc_p_b</a>
9859= <i>'neumann+inhomo'</i>&nbsp; is not allowed. </p>
9860
9861
9862
9863
9864
9865
9866
9867     
9868     
9869     
9870     
9871     
9872     
9873      <p>The roughness length is declared via the parameter <a href="#roughness_length">roughness_length</a>.</p>
9874
9875
9876
9877
9878
9879
9880
9881      </td>
9882
9883
9884
9885
9886
9887
9888 </tr>
9889
9890
9891
9892
9893
9894
9895 <tr>
9896
9897
9898
9899
9900
9901
9902 <td style="vertical-align: top;"> 
9903     
9904     
9905     
9906     
9907     
9908     
9909      <p><a name="precipitation"></a><b>precipitation</b></p>
9910
9911
9912
9913
9914
9915
9916
9917      </td>
9918
9919
9920
9921
9922
9923
9924 <td style="vertical-align: top;">L</td>
9925
9926
9927
9928
9929
9930
9931
9932      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9933
9934
9935
9936
9937
9938
9939 <td style="vertical-align: top;"> 
9940     
9941     
9942     
9943     
9944     
9945     
9946      <p>Parameter to switch
9947on the precipitation scheme.<br>
9948
9949
9950
9951
9952
9953
9954 </p>
9955
9956
9957
9958
9959
9960
9961 
9962     
9963     
9964     
9965     
9966     
9967     
9968      <p>For
9969precipitation processes PALM uses a simplified Kessler
9970scheme. This scheme only considers the
9971so-called autoconversion, that means the generation of rain water by
9972coagulation of cloud drops among themselves. Precipitation begins and
9973is immediately removed from the flow as soon as the liquid water
9974content exceeds the critical value of 0.5 g/kg.</p>
9975
9976
9977
9978
9979
9980
9981     
9982     
9983     
9984     
9985     
9986     
9987      <p>The precipitation rate and amount can be output by assigning the runtime parameter <a href="chapter_4.2.html#data_output">data_output</a> = <span style="font-style: italic;">'prr*'</span> or <span style="font-style: italic;">'pra*'</span>, respectively. The time interval on which the precipitation amount is defined can be controlled via runtime parameter <a href="chapter_4.2.html#precipitation_amount_interval">precipitation_amount_interval</a>.</p>
9988
9989
9990
9991
9992
9993
9994 </td>
9995
9996
9997
9998
9999
10000
10001 </tr>
10002
10003
10004
10005
10006
10007
10008
10009    <tr>
10010
10011
10012
10013
10014
10015
10016      <td style="vertical-align: top;"><a name="pt_reference"></a><span style="font-weight: bold;">pt_reference</span></td>
10017
10018
10019
10020
10021
10022
10023      <td style="vertical-align: top;">R</td>
10024
10025
10026
10027
10028
10029
10030      <td style="vertical-align: top;"><span style="font-style: italic;">use horizontal average as
10031refrence</span></td>
10032
10033
10034
10035
10036
10037
10038      <td style="vertical-align: top;">Reference
10039temperature to be used in all buoyancy terms (in K).<br>
10040
10041
10042
10043
10044
10045
10046      <br>
10047
10048
10049
10050
10051
10052
10053By
10054default, the instantaneous horizontal average over the total model
10055domain is used.<br>
10056
10057
10058
10059
10060
10061
10062      <br>
10063
10064
10065
10066
10067
10068
10069      <span style="font-weight: bold;">Attention:</span><br>
10070
10071
10072
10073
10074
10075
10076In case of ocean runs (see <a href="chapter_4.1.html#ocean">ocean</a>), always a reference temperature is used in the buoyancy terms with a default value of <span style="font-weight: bold;">pt_reference</span> = <a href="#pt_surface">pt_surface</a>.</td>
10077
10078
10079
10080
10081
10082
10083    </tr>
10084
10085
10086
10087
10088
10089
10090    <tr>
10091
10092
10093
10094
10095
10096
10097 <td style="vertical-align: top;"> 
10098     
10099     
10100     
10101     
10102     
10103     
10104      <p><a name="pt_surface"></a><b>pt_surface</b></p>
10105
10106
10107
10108
10109
10110
10111
10112      </td>
10113
10114
10115
10116
10117
10118
10119 <td style="vertical-align: top;">R</td>
10120
10121
10122
10123
10124
10125
10126
10127      <td style="vertical-align: top;"><i>300.0</i></td>
10128
10129
10130
10131
10132
10133
10134
10135      <td style="vertical-align: top;"> 
10136     
10137     
10138     
10139     
10140     
10141     
10142      <p>Surface
10143potential temperature (in K).&nbsp; </p>
10144
10145
10146
10147
10148
10149
10150 
10151     
10152     
10153     
10154     
10155     
10156     
10157      <p>This
10158parameter assigns the value of the potential temperature
10159      <span style="font-weight: bold;">pt</span> at the surface (k=0)<b>.</b> Starting from this value,
10160the
10161initial vertical temperature profile is constructed with <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10162and <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level
10163      </a>.
10164This profile is also used for the 1d-model as a stationary profile.</p>
10165
10166
10167
10168
10169
10170
10171     
10172     
10173     
10174     
10175     
10176     
10177      <p><span style="font-weight: bold;">Attention:</span><br>
10178
10179
10180
10181
10182
10183
10184In case of ocean runs (see <a href="#ocean">ocean</a>),
10185this parameter gives the temperature value at the sea surface, which is
10186at k=nzt. The profile is then constructed from the surface down to the
10187bottom of the model.</p>
10188
10189
10190
10191
10192
10193
10194
10195      </td>
10196
10197
10198
10199
10200
10201
10202 </tr>
10203
10204
10205
10206
10207
10208
10209 <tr>
10210
10211
10212
10213
10214
10215
10216 <td style="vertical-align: top;"> 
10217     
10218     
10219     
10220     
10221     
10222     
10223      <p><a name="pt_surface_initial_change"></a><b>pt_surface_initial</b>
10224      <br>
10225
10226
10227
10228
10229
10230
10231 <b>_change</b></p>
10232
10233
10234
10235
10236
10237
10238 </td>
10239
10240
10241
10242
10243
10244
10245 <td style="vertical-align: top;">R</td>
10246
10247
10248
10249
10250
10251
10252 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
10253
10254
10255
10256
10257
10258
10259 </td>
10260
10261
10262
10263
10264
10265
10266
10267      <td style="vertical-align: top;"> 
10268     
10269     
10270     
10271     
10272     
10273     
10274      <p>Change in
10275surface temperature to be made at the beginning of
10276the 3d run
10277(in K).&nbsp; </p>
10278
10279
10280
10281
10282
10283
10284 
10285     
10286     
10287     
10288     
10289     
10290     
10291      <p>If <b>pt_surface_initial_change</b>
10292is set to a non-zero
10293value, the near surface sensible heat flux is not allowed to be given
10294simultaneously (see <a href="#surface_heatflux">surface_heatflux</a>).</p>
10295
10296
10297
10298
10299
10300
10301
10302      </td>
10303
10304
10305
10306
10307
10308
10309 </tr>
10310
10311
10312
10313
10314
10315
10316 <tr>
10317
10318
10319
10320
10321
10322
10323 <td style="vertical-align: top;"> 
10324     
10325     
10326     
10327     
10328     
10329     
10330      <p><a name="pt_vertical_gradient"></a><b>pt_vertical_gradient</b></p>
10331
10332
10333
10334
10335
10336
10337
10338      </td>
10339
10340
10341
10342
10343
10344
10345 <td style="vertical-align: top;">R (10)</td>
10346
10347
10348
10349
10350
10351
10352
10353      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
10354
10355
10356
10357
10358
10359
10360
10361      <td style="vertical-align: top;"> 
10362     
10363     
10364     
10365     
10366     
10367     
10368      <p>Temperature
10369gradient(s) of the initial temperature profile (in
10370K
10371/ 100 m).&nbsp; </p>
10372
10373
10374
10375
10376
10377
10378 
10379     
10380     
10381     
10382     
10383     
10384     
10385      <p>This temperature gradient
10386holds starting from the height&nbsp;
10387level defined by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>
10388(precisely: for all uv levels k where zu(k) &gt;
10389pt_vertical_gradient_level,
10390pt_init(k) is set: pt_init(k) = pt_init(k-1) + dzu(k) * <b>pt_vertical_gradient</b>)
10391up to the top boundary or up to the next height level defined
10392by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>.
10393A total of 10 different gradients for 11 height intervals (10 intervals
10394if <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>(1)
10395= <i>0.0</i>) can be assigned. The surface temperature is
10396assigned via <a href="#pt_surface">pt_surface</a>.&nbsp;
10397      </p>
10398
10399
10400
10401
10402
10403
10404 
10405     
10406     
10407     
10408     
10409     
10410     
10411      <p>Example:&nbsp; </p>
10412
10413
10414
10415
10416
10417
10418 
10419     
10420     
10421     
10422     
10423     
10424     
10425      <ul>
10426
10427
10428
10429
10430
10431
10432 
10433       
10434       
10435       
10436       
10437       
10438       
10439        <p><b>pt_vertical_gradient</b>
10440= <i>1.0</i>, <i>0.5</i>,&nbsp; <br>
10441
10442
10443
10444
10445
10446
10447
10448        <b>pt_vertical_gradient_level</b> = <i>500.0</i>,
10449        <i>1000.0</i>,</p>
10450
10451
10452
10453
10454
10455
10456 
10457     
10458     
10459     
10460     
10461     
10462     
10463      </ul>
10464
10465
10466
10467
10468
10469
10470 
10471     
10472     
10473     
10474     
10475     
10476     
10477      <p>That
10478defines the temperature profile to be neutrally
10479stratified
10480up to z = 500.0 m with a temperature given by <a href="#pt_surface">pt_surface</a>.
10481For 500.0 m &lt; z &lt;= 1000.0 m the temperature gradient is
104821.0 K /
10483100 m and for z &gt; 1000.0 m up to the top boundary it is
104840.5 K / 100 m (it is assumed that the assigned height levels correspond
10485with uv levels).</p>
10486
10487
10488
10489
10490
10491
10492     
10493     
10494     
10495     
10496     
10497     
10498      <p><span style="font-weight: bold;">Attention:</span><br>
10499
10500
10501
10502
10503
10504
10505In case of ocean runs (see <a href="chapter_4.1.html#ocean">ocean</a>),
10506the profile is constructed like described above, but starting from the
10507sea surface (k=nzt) down to the bottom boundary of the model. Height
10508levels have then to be given as negative values, e.g. <span style="font-weight: bold;">pt_vertical_gradient_level</span> = <span style="font-style: italic;">-500.0</span>, <span style="font-style: italic;">-1000.0</span>.</p>
10509
10510
10511
10512
10513
10514
10515 </td>
10516
10517
10518
10519
10520
10521
10522 </tr>
10523
10524
10525
10526
10527
10528
10529 <tr>
10530
10531
10532
10533
10534
10535
10536 <td style="vertical-align: top;"> 
10537     
10538     
10539     
10540     
10541     
10542     
10543      <p><a name="pt_vertical_gradient_level"></a><b>pt_vertical_gradient</b>
10544      <br>
10545
10546
10547
10548
10549
10550
10551 <b>_level</b></p>
10552
10553
10554
10555
10556
10557
10558 </td>
10559
10560
10561
10562
10563
10564
10565 <td style="vertical-align: top;">R (10)</td>
10566
10567
10568
10569
10570
10571
10572 <td style="vertical-align: top;"> 
10573     
10574     
10575     
10576     
10577     
10578     
10579      <p><i>10 *</i>&nbsp;
10580      <span style="font-style: italic;">0.0</span><br>
10581
10582
10583
10584
10585
10586
10587
10588      </p>
10589
10590
10591
10592
10593
10594
10595 </td>
10596
10597
10598
10599
10600
10601
10602 <td style="vertical-align: top;">
10603     
10604     
10605     
10606     
10607     
10608     
10609      <p>Height level from which on the temperature gradient defined by
10610      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10611is effective (in m).&nbsp; </p>
10612
10613
10614
10615
10616
10617
10618 
10619     
10620     
10621     
10622     
10623     
10624     
10625      <p>The height levels have to be assigned in ascending order. The
10626default values result in a neutral stratification regardless of the
10627values of <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10628(unless the top boundary of the model is higher than 100000.0 m).
10629For the piecewise construction of temperature profiles see <a href="#pt_vertical_gradient">pt_vertical_gradient</a>.</p>
10630
10631
10632
10633
10634
10635
10636      <span style="font-weight: bold;">Attention:</span><br>
10637
10638
10639
10640
10641
10642
10643In case of ocean runs&nbsp;(see <a href="chapter_4.1.html#ocean">ocean</a>), the (negative) height levels have to be assigned in descending order.
10644      </td>
10645
10646
10647
10648
10649
10650
10651 </tr>
10652
10653
10654
10655
10656
10657
10658 <tr>
10659
10660
10661
10662
10663
10664
10665 <td style="vertical-align: top;"> 
10666     
10667     
10668     
10669     
10670     
10671     
10672      <p><a name="q_surface"></a><b>q_surface</b></p>
10673
10674
10675
10676
10677
10678
10679
10680      </td>
10681
10682
10683
10684
10685
10686
10687 <td style="vertical-align: top;">R</td>
10688
10689
10690
10691
10692
10693
10694
10695      <td style="vertical-align: top;"><i>0.0</i></td>
10696
10697
10698
10699
10700
10701
10702
10703      <td style="vertical-align: top;"> 
10704     
10705     
10706     
10707     
10708     
10709     
10710      <p>Surface
10711specific humidity / total water content (kg/kg).&nbsp; </p>
10712
10713
10714
10715
10716
10717
10718 
10719     
10720     
10721     
10722     
10723     
10724     
10725      <p>This
10726parameter assigns the value of the specific humidity q at
10727the surface (k=0).&nbsp; Starting from this value, the initial
10728humidity
10729profile is constructed with&nbsp; <a href="#q_vertical_gradient">q_vertical_gradient</a>
10730and <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
10731This profile is also used for the 1d-model as a stationary profile.</p>
10732
10733
10734
10735
10736
10737
10738
10739      </td>
10740
10741
10742
10743
10744
10745
10746 </tr>
10747
10748
10749
10750
10751
10752
10753 <tr>
10754
10755
10756
10757
10758
10759
10760 <td style="vertical-align: top;"> 
10761     
10762     
10763     
10764     
10765     
10766     
10767      <p><a name="q_surface_initial_change"></a><b>q_surface_initial</b>
10768      <br>
10769
10770
10771
10772
10773
10774
10775 <b>_change</b></p>
10776
10777
10778
10779
10780
10781
10782 </td>
10783
10784
10785
10786
10787
10788
10789 <td style="vertical-align: top;">R<br>
10790
10791
10792
10793
10794
10795
10796 </td>
10797
10798
10799
10800
10801
10802
10803 <td style="vertical-align: top;"><i>0.0</i></td>
10804
10805
10806
10807
10808
10809
10810
10811      <td style="vertical-align: top;"> 
10812     
10813     
10814     
10815     
10816     
10817     
10818      <p>Change in
10819surface specific humidity / total water content to
10820be made at the beginning
10821of the 3d run (kg/kg).&nbsp; </p>
10822
10823
10824
10825
10826
10827
10828 
10829     
10830     
10831     
10832     
10833     
10834     
10835      <p>If <b>q_surface_initial_change</b><i>
10836      </i>is set to a
10837non-zero value the
10838near surface latent heat flux (water flux) is not allowed to be given
10839simultaneously (see <a href="#surface_waterflux">surface_waterflux</a>).</p>
10840
10841
10842
10843
10844
10845
10846
10847      </td>
10848
10849
10850
10851
10852
10853
10854 </tr>
10855
10856
10857
10858
10859
10860
10861 <tr>
10862
10863
10864
10865
10866
10867
10868 <td style="vertical-align: top;"> 
10869     
10870     
10871     
10872     
10873     
10874     
10875      <p><a name="q_vertical_gradient"></a><b>q_vertical_gradient</b></p>
10876
10877
10878
10879
10880
10881
10882
10883      </td>
10884
10885
10886
10887
10888
10889
10890 <td style="vertical-align: top;">R (10)</td>
10891
10892
10893
10894
10895
10896
10897
10898      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
10899
10900
10901
10902
10903
10904
10905
10906      <td style="vertical-align: top;"> 
10907     
10908     
10909     
10910     
10911     
10912     
10913      <p>Humidity
10914gradient(s) of the initial humidity profile
10915(in 1/100 m).&nbsp; </p>
10916
10917
10918
10919
10920
10921
10922 
10923     
10924     
10925     
10926     
10927     
10928     
10929      <p>This humidity gradient
10930holds starting from the height
10931level&nbsp; defined by <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>
10932(precisely: for all uv levels k, where zu(k) &gt;
10933q_vertical_gradient_level,
10934q_init(k) is set: q_init(k) = q_init(k-1) + dzu(k) * <b>q_vertical_gradient</b>)
10935up to the top boundary or up to the next height level defined
10936by <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
10937A total of 10 different gradients for 11 height intervals (10 intervals
10938if <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>(1)
10939= <i>0.0</i>) can be asigned. The surface humidity is
10940assigned
10941via <a href="#q_surface">q_surface</a>. </p>
10942
10943
10944
10945
10946
10947
10948
10949     
10950     
10951     
10952     
10953     
10954     
10955      <p>Example:&nbsp; </p>
10956
10957
10958
10959
10960
10961
10962 
10963     
10964     
10965     
10966     
10967     
10968     
10969      <ul>
10970
10971
10972
10973
10974
10975
10976 
10977       
10978       
10979       
10980       
10981       
10982       
10983        <p><b>q_vertical_gradient</b>
10984= <i>0.001</i>, <i>0.0005</i>,&nbsp; <br>
10985
10986
10987
10988
10989
10990
10991
10992        <b>q_vertical_gradient_level</b> = <i>500.0</i>,
10993        <i>1000.0</i>,</p>
10994
10995
10996
10997
10998
10999
11000 
11001     
11002     
11003     
11004     
11005     
11006     
11007      </ul>
11008
11009
11010
11011
11012
11013
11014
11015That defines the humidity to be constant with height up to z =
11016500.0
11017m with a
11018value given by <a href="#q_surface">q_surface</a>.
11019For 500.0 m &lt; z &lt;= 1000.0 m the humidity gradient is
110200.001 / 100
11021m and for z &gt; 1000.0 m up to the top boundary it is
110220.0005 / 100 m (it is assumed that the assigned height levels
11023correspond with uv
11024levels). </td>
11025
11026
11027
11028
11029
11030
11031 </tr>
11032
11033
11034
11035
11036
11037
11038 <tr>
11039
11040
11041
11042
11043
11044
11045 <td style="vertical-align: top;"> 
11046     
11047     
11048     
11049     
11050     
11051     
11052      <p><a name="q_vertical_gradient_level"></a><b>q_vertical_gradient</b>
11053      <br>
11054
11055
11056
11057
11058
11059
11060 <b>_level</b></p>
11061
11062
11063
11064
11065
11066
11067 </td>
11068
11069
11070
11071
11072
11073
11074 <td style="vertical-align: top;">R (10)</td>
11075
11076
11077
11078
11079
11080
11081 <td style="vertical-align: top;"> 
11082     
11083     
11084     
11085     
11086     
11087     
11088      <p><i>10 *</i>&nbsp;
11089      <i>0.0</i></p>
11090
11091
11092
11093
11094
11095
11096 </td>
11097
11098
11099
11100
11101
11102
11103 <td style="vertical-align: top;"> 
11104     
11105     
11106     
11107     
11108     
11109     
11110      <p>Height level from
11111which on the humidity gradient defined by <a href="#q_vertical_gradient">q_vertical_gradient</a>
11112is effective (in m).&nbsp; </p>
11113
11114
11115
11116
11117
11118
11119 
11120     
11121     
11122     
11123     
11124     
11125     
11126      <p>The height levels
11127are to be assigned in ascending order. The
11128default values result in a humidity constant with height regardless of
11129the values of <a href="#q_vertical_gradient">q_vertical_gradient</a>
11130(unless the top boundary of the model is higher than 100000.0 m). For
11131the piecewise construction of humidity profiles see <a href="#q_vertical_gradient">q_vertical_gradient</a>.</p>
11132
11133
11134
11135
11136
11137
11138
11139      </td>
11140
11141
11142
11143
11144
11145
11146 </tr>
11147
11148
11149
11150
11151
11152
11153 <tr>
11154
11155
11156
11157
11158
11159
11160 <td style="vertical-align: top;"> 
11161     
11162     
11163     
11164     
11165     
11166     
11167      <p><a name="radiation"></a><b>radiation</b></p>
11168
11169
11170
11171
11172
11173
11174
11175      </td>
11176
11177
11178
11179
11180
11181
11182 <td style="vertical-align: top;">L</td>
11183
11184
11185
11186
11187
11188
11189
11190      <td style="vertical-align: top;"><i>.F.</i></td>
11191
11192
11193
11194
11195
11196
11197
11198      <td style="vertical-align: top;"> 
11199     
11200     
11201     
11202     
11203     
11204     
11205      <p>Parameter to
11206switch on longwave radiation cooling at
11207cloud-tops.&nbsp; </p>
11208
11209
11210
11211
11212
11213
11214 
11215     
11216     
11217     
11218     
11219     
11220     
11221      <p>Long-wave radiation
11222processes are parameterized by the
11223effective emissivity, which considers only the absorption and