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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="#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="#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><td style="vertical-align: top;"><p><a name="humidity"></a><b>humidity</b></p></td><td style="vertical-align: top;">L</td><td style="vertical-align: top;"><i>.F.</i></td><td style="vertical-align: top;"><p>Parameter to
5513switch on the prognostic equation for specific
5514humidity q.<br>
5515
5516
5517
5518
5519
5520
5521 </p>
5522
5523
5524
5525
5526
5527
5528 
5529     
5530     
5531     
5532     
5533     
5534     
5535      <p>The initial vertical
5536profile 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>
5537and <a href="chapter_4.1.html#q_vertical_gradient_level">q_vertical_gradient_level</a>.&nbsp;
5538Boundary conditions can be set via <a href="chapter_4.1.html#q_surface_initial_change">q_surface_initial_change</a>
5539and <a href="chapter_4.1.html#surface_waterflux">surface_waterflux</a>.<br>
5540
5541
5542
5543
5544
5545
5546
5547      </p>
5548
5549
5550
5551
5552
5553
5554
5555If the condensation scheme is switched on (<a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
5556= .TRUE.), q becomes the total liquid water content (sum of specific
5557humidity and liquid water content).</td></tr><tr><td style="vertical-align: top;"><span style="font-weight: bold;"><a name="inflow_damping_height"></a>inflow_damping_height</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><span style="font-style: italic;">from precursor run</span></td><td style="vertical-align: top;">Height below which the turbulence signal is used for turbulence recycling (in m).<br><br>In case of a turbulent inflow (see <a href="chapter_4.1.html#turbulent_inflow">turbulent_inflow</a>),
5558this parameter defines the vertical thickness of the turbulent layer up
5559to which the turbulence extracted at the recycling plane (see <a href="chapter_4.1.html#recycling_width">recycling_width</a>)
5560shall be imposed to the inflow. Above this level the turbulence signal
5561is linearly damped to zero. The transition range within which the
5562signal falls to zero is given by the parameter <a href="chapter_4.1.html#inflow_damping_width">inflow_damping_width</a>.<br><br>By default, this height is set as the height of the convective boundary layer as calculated from a precursor run. See <a href="chapter_3.9.html">chapter 3.9</a> about proper settings for getting this CBL height from a precursor run. </td></tr><tr><td style="vertical-align: top;"><span style="font-weight: bold;"><a name="inflow_damping_width"></a>inflow_damping_width</span></td><td style="vertical-align: top;">R</td><td style="vertical-align: top;"><span style="font-style: italic;">0.1 * <a href="chapter_4.1.html#inflow_damping_height">inflow_damping</a></span><a href="chapter_4.1.html#inflow_damping_height"><br style="font-style: italic;"><span style="font-style: italic;">_height</span></a></td><td style="vertical-align: top;">Transition range within which the turbulance signal is damped to zero (in m).<br><br>See <a href="chapter_4.1.html#inflow_damping_height">inflow_damping_height</a> for explanation.</td></tr><tr>
5563
5564
5565
5566
5567
5568
5569 <td style="vertical-align: top;"><a name="inflow_disturbance_begin"></a><b>inflow_disturbance_<br>
5570
5571
5572
5573
5574
5575
5576
5577begin</b></td>
5578
5579
5580
5581
5582
5583
5584 <td style="vertical-align: top;">I</td>
5585
5586
5587
5588
5589
5590
5591
5592      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(10,</span><br style="font-style: italic;">
5593
5594
5595
5596
5597
5598
5599 <span style="font-style: italic;">nx/2 or ny/2)</span></td>
5600
5601
5602
5603
5604
5605
5606
5607      <td style="vertical-align: top;">Lower
5608limit of the horizontal range for which random perturbations are to be
5609imposed on the horizontal velocity field (gridpoints).<br>
5610
5611
5612
5613
5614
5615
5616 <br>
5617
5618
5619
5620
5621
5622
5623
5624If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5625or <a href="#bc_ns">bc_ns</a>),
5626this parameter gives the gridpoint number (counted horizontally from
5627the inflow)&nbsp; from which on perturbations are imposed on the
5628horizontal velocity field. Perturbations must be switched on with
5629parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5630
5631
5632
5633
5634
5635
5636
5637    </tr>
5638
5639
5640
5641
5642
5643
5644 <tr>
5645
5646
5647
5648
5649
5650
5651 <td style="vertical-align: top;"><a name="inflow_disturbance_end"></a><b>inflow_disturbance_<br>
5652
5653
5654
5655
5656
5657
5658
5659end</b></td>
5660
5661
5662
5663
5664
5665
5666 <td style="vertical-align: top;">I</td>
5667
5668
5669
5670
5671
5672
5673
5674      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(100,</span><br style="font-style: italic;">
5675
5676
5677
5678
5679
5680
5681 <span style="font-style: italic;">3/4*nx or</span><br style="font-style: italic;">
5682
5683
5684
5685
5686
5687
5688 <span style="font-style: italic;">3/4*ny)</span></td>
5689
5690
5691
5692
5693
5694
5695 <td style="vertical-align: top;">Upper
5696limit of the horizontal range for which random perturbations are
5697to be imposed on the horizontal velocity field (gridpoints).<br>
5698
5699
5700
5701
5702
5703
5704 <br>
5705
5706
5707
5708
5709
5710
5711
5712If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5713or <a href="#bc_ns">bc_ns</a>),
5714this parameter gives the gridpoint number (counted horizontally from
5715the inflow)&nbsp; unto which perturbations are imposed on the
5716horizontal
5717velocity field. Perturbations must be switched on with parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5718
5719
5720
5721
5722
5723
5724
5725    </tr>
5726
5727
5728
5729
5730
5731
5732 <tr>
5733
5734
5735
5736
5737
5738
5739 <td style="vertical-align: top;">
5740     
5741     
5742     
5743     
5744     
5745     
5746      <p><a name="initializing_actions"></a><b>initializing_actions</b></p>
5747
5748
5749
5750
5751
5752
5753
5754      </td>
5755
5756
5757
5758
5759
5760
5761 <td style="vertical-align: top;">C * 100</td>
5762
5763
5764
5765
5766
5767
5768
5769      <td style="vertical-align: top;"><br>
5770
5771
5772
5773
5774
5775
5776 </td>
5777
5778
5779
5780
5781
5782
5783 <td style="vertical-align: top;"> 
5784     
5785     
5786     
5787     
5788     
5789     
5790      <p style="font-style: normal;">Initialization actions
5791to be carried out.&nbsp; </p>
5792
5793
5794
5795
5796
5797
5798 
5799     
5800     
5801     
5802     
5803     
5804     
5805      <p style="font-style: normal;">This parameter does not have a
5806default value and therefore must be assigned with each model run. For
5807restart runs <b>initializing_actions</b> = <span style="font-style: italic;">'read_restart_data'</span>
5808must be set. For the initial run of a job chain the following values
5809are allowed:&nbsp; </p>
5810
5811
5812
5813
5814
5815
5816 
5817     
5818     
5819     
5820     
5821     
5822     
5823      <p style="font-style: normal;"><span style="font-style: italic;">'set_constant_profiles'</span>
5824      </p>
5825
5826
5827
5828
5829
5830
5831 
5832     
5833     
5834     
5835     
5836     
5837     
5838      <ul>
5839
5840
5841
5842
5843
5844
5845 
5846       
5847       
5848       
5849       
5850       
5851       
5852        <p>A horizontal wind profile consisting
5853of linear sections (see <a href="#ug_surface">ug_surface</a>,
5854        <a href="#ug_vertical_gradient">ug_vertical_gradient</a>,
5855        <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>
5856and <a href="#vg_surface">vg_surface</a>, <a href="#vg_vertical_gradient">vg_vertical_gradient</a>,
5857        <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
5858respectively) as well as a vertical temperature (humidity) profile
5859consisting of
5860linear sections (see <a href="#pt_surface">pt_surface</a>,
5861        <a href="#pt_vertical_gradient">pt_vertical_gradient</a>,
5862        <a href="#q_surface">q_surface</a>
5863and <a href="#q_vertical_gradient">q_vertical_gradient</a>)
5864are assumed as initial profiles. The subgrid-scale TKE is set to 0 but K<sub>m</sub>
5865and K<sub>h</sub> are set to very small values because
5866otherwise no TKE
5867would be generated.</p>
5868
5869
5870
5871
5872
5873
5874 
5875     
5876     
5877     
5878     
5879     
5880     
5881      </ul>
5882
5883
5884
5885
5886
5887
5888 
5889     
5890     
5891     
5892     
5893     
5894     
5895      <p style="font-style: italic;">'set_1d-model_profiles' </p>
5896
5897
5898
5899
5900
5901
5902
5903     
5904     
5905     
5906     
5907     
5908     
5909      <ul>
5910
5911
5912
5913
5914
5915
5916 
5917       
5918       
5919       
5920       
5921       
5922       
5923        <p>The arrays of the 3d-model are initialized with
5924the
5925(stationary) solution of the 1d-model. These are the variables e, kh,
5926km, u, v and with Prandtl layer switched on rif, us, usws, vsws. The
5927temperature (humidity) profile consisting of linear sections is set as
5928for 'set_constant_profiles' and assumed as constant in time within the
59291d-model. For steering of the 1d-model a set of parameters with suffix
5930"_1d" (e.g. <a href="#end_time_1d">end_time_1d</a>,
5931        <a href="#damp_level_1d">damp_level_1d</a>)
5932is available.</p>
5933
5934
5935
5936
5937
5938
5939 
5940     
5941     
5942     
5943     
5944     
5945     
5946      </ul>
5947
5948
5949
5950
5951
5952
5953 
5954     
5955     
5956     
5957     
5958     
5959     
5960      <p><span style="font-style: italic;">'by_user'</span></p>
5961
5962
5963
5964
5965
5966
5967     
5968     
5969     
5970     
5971     
5972     
5973      <p style="margin-left: 40px;">The initialization of the arrays
5974of the 3d-model is under complete control of the user and has to be
5975done in routine <a href="chapter_3.5.1.html#user_init_3d_model">user_init_3d_model</a>
5976of the user-interface.<span style="font-style: italic;"></span></p>
5977
5978
5979
5980
5981
5982
5983     
5984     
5985     
5986     
5987     
5988     
5989      <p><span style="font-style: italic;">'initialize_vortex'</span>
5990      </p>
5991
5992
5993
5994
5995
5996
5997 
5998     
5999     
6000     
6001     
6002     
6003     
6004      <div style="margin-left: 40px;">The initial
6005velocity field of the
60063d-model corresponds to a
6007Rankine-vortex with vertical axis. This setting may be used to test
6008advection 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>)
6009are necessary. In order not to distort the vortex, an initial
6010horizontal wind profile constant
6011with height is necessary (to be set by <b>initializing_actions</b>
6012= <span style="font-style: italic;">'set_constant_profiles'</span>)
6013and some other conditions have to be met (neutral stratification,
6014diffusion must be
6015switched off, see <a href="#km_constant">km_constant</a>).
6016The center of the vortex is located at jc = (nx+1)/2. It
6017extends from k = 0 to k = nz+1. Its radius is 8 * <a href="#dx">dx</a>
6018and the exponentially decaying part ranges to 32 * <a href="#dx">dx</a>
6019(see init_rankine.f90). </div>
6020
6021
6022
6023
6024
6025
6026 
6027     
6028     
6029     
6030     
6031     
6032     
6033      <p><span style="font-style: italic;">'initialize_ptanom'</span>
6034      </p>
6035
6036
6037
6038
6039
6040
6041 
6042     
6043     
6044     
6045     
6046     
6047     
6048      <ul>
6049
6050
6051
6052
6053
6054
6055 
6056       
6057       
6058       
6059       
6060       
6061       
6062        <p>A 2d-Gauss-like shape disturbance
6063(x,y) is added to the
6064initial temperature field with radius 10.0 * <a href="#dx">dx</a>
6065and center at jc = (nx+1)/2. This may be used for tests of scalar
6066advection schemes
6067(see <a href="#scalar_advec">scalar_advec</a>).
6068Such tests require a horizontal wind profile constant with hight and
6069diffusion
6070switched off (see <span style="font-style: italic;">'initialize_vortex'</span>).
6071Additionally, the buoyancy term
6072must be switched of in the equation of motion&nbsp; for w (this
6073requires the user to comment out the call of <span style="font-family: monospace;">buoyancy</span> in the
6074source code of <span style="font-family: monospace;">prognostic_equations.f90</span>).</p></ul>
6075
6076
6077
6078
6079
6080
6081 
6082     
6083     
6084     
6085     
6086     
6087     
6088      <p style="font-style: italic;">'read_data_for_recycling'</p><p style="font-style: normal; margin-left: 40px;">Here,
60893d-data from a precursor run are read by the initial (main) run. The
6090precursor run is allowed to have a smaller domain along x and y
6091compared with the main run. Also, different numbers of processors can
6092be used for these two runs. Limitations are that the precursor run must
6093use cyclic horizontal boundary conditions and that the subdomains of
6094the main run must not be larger than the subdomains of the precursor
6095run. If the total domain of the main run is larger than that of the precursor
6096run, the domain is filled by cyclic repetition&nbsp;of the (cyclic)
6097precursor data. This initialization method is recommended if a
6098turbulent inflow is used (see <a href="chapter_4.1.html#turbulent_inflow">turbulent_inflow</a>). 3d-data must be made available to the run by activating an appropriate file connection statement for local file BININ. See <a href="chapter_3.9.html">chapter 3.9</a> for more details, where usage of a turbulent inflow is explained. </p><p style="font-style: normal;">Values may be
6099combined, e.g. <b>initializing_actions</b> = <span style="font-style: italic;">'set_constant_profiles
6100initialize_vortex'</span>, but the values of <span style="font-style: italic;">'set_constant_profiles'</span>,
6101      <span style="font-style: italic;">'set_1d-model_profiles'</span>
6102, and <span style="font-style: italic;">'by_user'</span>
6103must not be given at the same time.</p>
6104
6105
6106
6107
6108
6109
6110 
6111     
6112     
6113     
6114     
6115     
6116     
6117     
6118
6119
6120
6121
6122
6123
6124 </td>
6125
6126
6127
6128
6129
6130
6131 </tr>
6132
6133
6134
6135
6136
6137
6138
6139    <tr>
6140
6141
6142
6143
6144
6145
6146 <td style="vertical-align: top;"> 
6147     
6148     
6149     
6150     
6151     
6152     
6153      <p><a name="km_constant"></a><b>km_constant</b></p>
6154
6155
6156
6157
6158
6159
6160
6161      </td>
6162
6163
6164
6165
6166
6167
6168 <td style="vertical-align: top;">R</td>
6169
6170
6171
6172
6173
6174
6175
6176      <td style="vertical-align: top;"><i>variable<br>
6177
6178
6179
6180
6181
6182
6183
6184(computed from TKE)</i></td>
6185
6186
6187
6188
6189
6190
6191 <td style="vertical-align: top;"> 
6192     
6193     
6194     
6195     
6196     
6197     
6198      <p>Constant eddy
6199diffusivities are used (laminar
6200simulations).&nbsp; </p>
6201
6202
6203
6204
6205
6206
6207 
6208     
6209     
6210     
6211     
6212     
6213     
6214      <p>If this parameter is
6215specified, both in the 1d and in the
62163d-model constant values for the eddy diffusivities are used in
6217space and time with K<sub>m</sub> = <b>km_constant</b>
6218and K<sub>h</sub> = K<sub>m</sub> / <a href="chapter_4.2.html#prandtl_number">prandtl_number</a>.
6219The prognostic equation for the subgrid-scale TKE is switched off.
6220Constant eddy diffusivities are only allowed with the Prandtl layer (<a href="#prandtl_layer">prandtl_layer</a>)
6221switched off.</p>
6222
6223
6224
6225
6226
6227
6228 </td>
6229
6230
6231
6232
6233
6234
6235 </tr>
6236
6237
6238
6239
6240
6241
6242 <tr>
6243
6244
6245
6246
6247
6248
6249 <td style="vertical-align: top;"> 
6250     
6251     
6252     
6253     
6254     
6255     
6256      <p><a name="km_damp_max"></a><b>km_damp_max</b></p>
6257
6258
6259
6260
6261
6262
6263
6264      </td>
6265
6266
6267
6268
6269
6270
6271 <td style="vertical-align: top;">R</td>
6272
6273
6274
6275
6276
6277
6278
6279      <td style="vertical-align: top;"><span style="font-style: italic;">0.5*(dx
6280or dy)</span></td>
6281
6282
6283
6284
6285
6286
6287 <td style="vertical-align: top;">Maximum
6288diffusivity used for filtering the velocity field in the vicinity of
6289the outflow (in m<sup>2</sup>/s).<br>
6290
6291
6292
6293
6294
6295
6296 <br>
6297
6298
6299
6300
6301
6302
6303
6304When using non-cyclic lateral boundaries (see <a href="#bc_lr">bc_lr</a>
6305or <a href="#bc_ns">bc_ns</a>),
6306a smoothing has to be applied to the
6307velocity field in the vicinity of the outflow in order to suppress any
6308reflections of outgoing disturbances. Smoothing is done by increasing
6309the eddy diffusivity along the horizontal direction which is
6310perpendicular to the outflow boundary. Only velocity components
6311parallel to the outflow boundary are filtered (e.g. v and w, if the
6312outflow is along x). Damping is applied from the bottom to the top of
6313the domain.<br>
6314
6315
6316
6317
6318
6319
6320 <br>
6321
6322
6323
6324
6325
6326
6327
6328The horizontal range of the smoothing is controlled by <a href="#outflow_damping_width">outflow_damping_width</a>
6329which defines the number of gridpoints (counted from the outflow
6330boundary) from where on the smoothing is applied. Starting from that
6331point, the eddy diffusivity is linearly increased (from zero to its
6332maximum value given by <span style="font-weight: bold;">km_damp_max</span>)
6333until half of the damping range width, from where it remains constant
6334up to the outflow boundary. If at a certain grid point the eddy
6335diffusivity calculated from the flow field is larger than as described
6336above, it is used instead.<br>
6337
6338
6339
6340
6341
6342
6343 <br>
6344
6345
6346
6347
6348
6349
6350
6351The default value of <span style="font-weight: bold;">km_damp_max</span>
6352has been empirically proven to be sufficient.</td>
6353
6354
6355
6356
6357
6358
6359 </tr>
6360
6361
6362
6363
6364
6365
6366 <tr>
6367
6368      <td style="vertical-align: top;"><a name="lad_surface"></a><span style="font-weight: bold;">lad_surface</span></td>
6369
6370      <td style="vertical-align: top;">R</td>
6371
6372      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
6373
6374      <td style="vertical-align: top;">Surface value of the leaf area density (in m<sup>2</sup>/m<sup>3</sup>).<br>
6375
6376      <br>
6377
6378This
6379parameter 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,
6380the leaf area density profile is constructed with <a href="#lad_vertical_gradient">lad_vertical_gradient</a>
6381and <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level
6382      </a>.</td>
6383
6384    </tr>
6385
6386    <tr>
6387
6388      <td style="vertical-align: top;"><a name="lad_vertical_gradient"></a><span style="font-weight: bold;">lad_vertical_gradient</span></td>
6389
6390      <td style="vertical-align: top;">R (10)</td>
6391
6392      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6393
6394      <td style="vertical-align: top;">Gradient(s) of the leaf area density (in&nbsp;m<sup>2</sup>/m<sup>4</sup>).<br>
6395
6396      <br>
6397
6398     
6399      <p>This leaf area density gradient
6400holds starting from the height&nbsp;
6401level defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6402(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>)
6403up 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
6404if <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>(1)
6405= <i>0.0</i>) can be assigned. The leaf area density at the surface is
6406assigned via <a href="#lad_surface">lad_surface</a>.&nbsp;
6407      </p>
6408
6409      </td>
6410
6411    </tr>
6412
6413    <tr>
6414
6415      <td style="vertical-align: top;"><a name="lad_vertical_gradient_level"></a><span style="font-weight: bold;">lad_vertical_gradient_level</span></td>
6416
6417      <td style="vertical-align: top;">R (10)</td>
6418
6419      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6420
6421      <td style="vertical-align: top;">Height level from which on the&nbsp;gradient
6422of the leaf area density defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6423is effective (in m).<br>
6424
6425      <br>
6426
6427The height levels have to be assigned in ascending order. The
6428default 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="#lad_vertical_gradient">lad_vertical_gradient</a>.</td>
6429
6430    </tr>
6431
6432    <tr>
6433
6434      <td style="vertical-align: top;"><a name="leaf_surface_concentration"></a><b>leaf_surface_concentration</b></td>
6435
6436      <td style="vertical-align: top;">R</td>
6437
6438      <td style="vertical-align: top;"><i>0.0</i></td>
6439
6440      <td style="vertical-align: top;">Concentration of a passive scalar at the surface of a leaf (in K m/s).<br>
6441
6442
6443      <br>
6444
6445
6446This parameter is only of importance in cases in that both, <a href="#plant_canopy">plant_canopy</a> and <a href="#passive_scalar">passive_scalar</a>, are set <span style="font-style: italic;">.T.</span>.
6447The value of the concentration of a passive scalar at the surface of a
6448leaf is required for the parametrisation of the sources and sinks of
6449scalar concentration due to the canopy.</td>
6450
6451    </tr>
6452
6453    <tr>
6454
6455
6456
6457
6458
6459
6460
6461      <td style="vertical-align: top;"> 
6462     
6463     
6464     
6465     
6466     
6467     
6468      <p><a name="long_filter_factor"></a><b>long_filter_factor</b></p>
6469
6470
6471
6472
6473
6474
6475
6476      </td>
6477
6478
6479
6480
6481
6482
6483 <td style="vertical-align: top;">R</td>
6484
6485
6486
6487
6488
6489
6490
6491      <td style="vertical-align: top;"><i>0.0</i></td>
6492
6493
6494
6495
6496
6497
6498
6499      <td style="vertical-align: top;"> 
6500     
6501     
6502     
6503     
6504     
6505     
6506      <p>Filter factor
6507for the so-called Long-filter.<br>
6508
6509
6510
6511
6512
6513
6514 </p>
6515
6516
6517
6518
6519
6520
6521 
6522     
6523     
6524     
6525     
6526     
6527     
6528      <p><br>
6529
6530
6531
6532
6533
6534
6535
6536This filter very efficiently
6537eliminates 2-delta-waves sometimes cauesed by the upstream-spline
6538scheme (see Mahrer and
6539Pielke, 1978: Mon. Wea. Rev., 106, 818-830). It works in all three
6540directions in space. A value of <b>long_filter_factor</b>
6541= <i>0.01</i>
6542sufficiently removes the small-scale waves without affecting the
6543longer waves.<br>
6544
6545
6546
6547
6548
6549
6550 </p>
6551
6552
6553
6554
6555
6556
6557 
6558     
6559     
6560     
6561     
6562     
6563     
6564      <p>By default, the filter is
6565switched off (= <i>0.0</i>).
6566It is exclusively applied to the tendencies calculated by the
6567upstream-spline scheme (see <a href="#momentum_advec">momentum_advec</a>
6568and <a href="#scalar_advec">scalar_advec</a>),
6569not to the prognostic variables themselves. At the bottom and top
6570boundary of the model domain the filter effect for vertical
65712-delta-waves is reduced. There, the amplitude of these waves is only
6572reduced by approx. 50%, otherwise by nearly 100%.&nbsp; <br>
6573
6574
6575
6576
6577
6578
6579
6580Filter factors with values &gt; <i>0.01</i> also
6581reduce the amplitudes
6582of waves with wavelengths longer than 2-delta (see the paper by Mahrer
6583and
6584Pielke, quoted above). </p>
6585
6586
6587
6588
6589
6590
6591 </td>
6592
6593
6594
6595
6596
6597
6598 </tr>
6599
6600
6601
6602
6603
6604
6605 <tr>
6606
6607
6608
6609
6610
6611
6612      <td style="vertical-align: top;"><a name="loop_optimization"></a><span style="font-weight: bold;">loop_optimization</span></td>
6613
6614
6615
6616
6617
6618
6619      <td style="vertical-align: top;">C*16</td>
6620
6621
6622
6623
6624
6625
6626      <td style="vertical-align: top;"><span style="font-style: italic;">see right</span></td>
6627
6628
6629
6630
6631
6632
6633      <td>Method used to optimize loops for solving the prognostic equations .<br>
6634
6635
6636
6637
6638
6639
6640      <br>
6641
6642
6643
6644
6645
6646
6647By
6648default, the optimization method depends on the host on which PALM is
6649running. On machines with vector-type CPUs, single 3d-loops are used to
6650calculate each tendency term of each prognostic equation, while on all
6651other machines, all prognostic equations are solved within one big loop
6652over 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>
6653
6654
6655
6656
6657
6658
6659      <br>
6660
6661
6662
6663
6664
6665
6666The 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>
6667
6668
6669
6670
6671
6672
6673    </tr>
6674
6675
6676
6677
6678
6679
6680    <tr>
6681
6682
6683
6684
6685
6686
6687
6688      <td style="vertical-align: top;"><a name="mixing_length_1d"></a><span style="font-weight: bold;">mixing_length_1d</span><br>
6689
6690
6691
6692
6693
6694
6695
6696      </td>
6697
6698
6699
6700
6701
6702
6703 <td style="vertical-align: top;">C*20<br>
6704
6705
6706
6707
6708
6709
6710
6711      </td>
6712
6713
6714
6715
6716
6717
6718 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
6719
6720
6721
6722
6723
6724
6725 <span style="font-style: italic;">model'</span><br>
6726
6727
6728
6729
6730
6731
6732 </td>
6733
6734
6735
6736
6737
6738
6739
6740      <td style="vertical-align: top;">Mixing length used in the
67411d-model.<br>
6742
6743
6744
6745
6746
6747
6748 <br>
6749
6750
6751
6752
6753
6754
6755
6756By default the mixing length is calculated as in the 3d-model (i.e. it
6757depends on the grid spacing).<br>
6758
6759
6760
6761
6762
6763
6764 <br>
6765
6766
6767
6768
6769
6770
6771
6772By setting <span style="font-weight: bold;">mixing_length_1d</span>
6773= <span style="font-style: italic;">'blackadar'</span>,
6774the so-called Blackadar mixing length is used (l = kappa * z / ( 1 +
6775kappa * z / lambda ) with the limiting value lambda = 2.7E-4 * u_g / f).<br>
6776
6777
6778
6779
6780
6781
6782
6783      </td>
6784
6785
6786
6787
6788
6789
6790 </tr>
6791
6792
6793
6794
6795
6796
6797 
6798
6799
6800
6801
6802
6803
6804
6805    <tr>
6806
6807
6808
6809
6810
6811
6812 <td style="vertical-align: top;"> 
6813     
6814     
6815     
6816     
6817     
6818     
6819      <p><a name="momentum_advec"></a><b>momentum_advec</b></p>
6820
6821
6822
6823
6824
6825
6826
6827      </td>
6828
6829
6830
6831
6832
6833
6834 <td style="vertical-align: top;">C * 10</td>
6835
6836
6837
6838
6839
6840
6841
6842      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
6843
6844
6845
6846
6847
6848
6849
6850      <td style="vertical-align: top;"> 
6851     
6852     
6853     
6854     
6855     
6856     
6857      <p>Advection
6858scheme to be used for the momentum equations.<br>
6859
6860
6861
6862
6863
6864
6865 <br>
6866
6867
6868
6869
6870
6871
6872
6873The user can choose between the following schemes:<br>
6874
6875
6876
6877
6878
6879
6880
6881&nbsp;<br>
6882
6883
6884
6885
6886
6887
6888 <br>
6889
6890
6891
6892
6893
6894
6895 <span style="font-style: italic;">'pw-scheme'</span><br>
6896
6897
6898
6899
6900
6901
6902
6903      </p>
6904
6905
6906
6907
6908
6909
6910 
6911     
6912     
6913     
6914     
6915     
6916     
6917      <div style="margin-left: 40px;">The scheme of
6918Piascek and
6919Williams (1970, J. Comp. Phys., 6,
6920392-405) with central differences in the form C3 is used.<br>
6921
6922
6923
6924
6925
6926
6927
6928If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
6929= <span style="font-style: italic;">'leapfrog+euler'</span>
6930the
6931advection scheme is - for the Euler-timestep - automatically switched
6932to an upstream-scheme.<br>
6933
6934
6935
6936
6937
6938
6939 </div>
6940
6941
6942
6943
6944
6945
6946 
6947     
6948     
6949     
6950     
6951     
6952     
6953      <p> </p>
6954
6955
6956
6957
6958
6959
6960 
6961     
6962     
6963     
6964     
6965     
6966     
6967      <p><span style="font-style: italic;">'ups-scheme'</span><br>
6968
6969
6970
6971
6972
6973
6974
6975      </p>
6976
6977
6978
6979
6980
6981
6982 
6983     
6984     
6985     
6986     
6987     
6988     
6989      <div style="margin-left: 40px;">The
6990upstream-spline scheme is
6991used
6992(see Mahrer and Pielke,
69931978: Mon. Wea. Rev., 106, 818-830). In opposite to the
6994Piascek-Williams scheme, this is characterized by much better numerical
6995features (less numerical diffusion, better preservation of flow
6996structures, e.g. vortices), but computationally it is much more
6997expensive. In
6998addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
6999= <span style="font-style: italic;">'</span><i>euler'</i>),
7000i.e. the
7001timestep accuracy is only of first order.
7002For this reason the advection of scalar variables (see <a href="#scalar_advec">scalar_advec</a>)
7003should then also be carried out with the upstream-spline scheme,
7004because otherwise the scalar variables would
7005be subject to large numerical diffusion due to the upstream
7006scheme.&nbsp; </div>
7007
7008
7009
7010
7011
7012
7013 
7014     
7015     
7016     
7017     
7018     
7019     
7020      <p style="margin-left: 40px;">Since
7021the cubic splines used tend
7022to overshoot under
7023certain circumstances, this effect must be adjusted by suitable
7024filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
7025      <a href="#long_filter_factor">long_filter_factor</a>,
7026      <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>).
7027This is always neccessary for runs with stable stratification,
7028even if this stratification appears only in parts of the model domain.<br>
7029
7030
7031
7032
7033
7034
7035
7036      </p>
7037
7038
7039
7040
7041
7042
7043 
7044     
7045     
7046     
7047     
7048     
7049     
7050      <div style="margin-left: 40px;">With stable
7051stratification the
7052upstream-spline scheme also
7053produces gravity waves with large amplitude, which must be
7054suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
7055
7056
7057
7058
7059
7060
7061
7062      <br>
7063
7064
7065
7066
7067
7068
7069 <span style="font-weight: bold;">Important: </span>The&nbsp;
7070upstream-spline scheme is not implemented for humidity and passive
7071scalars (see&nbsp;<a href="#humidity">humidity</a>
7072and <a href="#passive_scalar">passive_scalar</a>)
7073and requires the use of a 2d-domain-decomposition. The last conditions
7074severely restricts code optimization on several machines leading to
7075very long execution times! The scheme is also not allowed for
7076non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
7077and <a href="#bc_ns">bc_ns</a>).</div>
7078
7079
7080
7081
7082
7083
7084 </td>
7085
7086
7087
7088
7089
7090
7091
7092    </tr>
7093
7094
7095
7096
7097
7098
7099 <tr>
7100
7101
7102
7103
7104
7105
7106 <td style="vertical-align: top;"><a name="netcdf_precision"></a><span style="font-weight: bold;">netcdf_precision</span><br>
7107
7108
7109
7110
7111
7112
7113
7114      </td>
7115
7116
7117
7118
7119
7120
7121 <td style="vertical-align: top;">C*20<br>
7122
7123
7124
7125
7126
7127
7128
7129(10)<br>
7130
7131
7132
7133
7134
7135
7136 </td>
7137
7138
7139
7140
7141
7142
7143 <td style="vertical-align: top;"><span style="font-style: italic;">single preci-</span><br style="font-style: italic;">
7144
7145
7146
7147
7148
7149
7150 <span style="font-style: italic;">sion for all</span><br style="font-style: italic;">
7151
7152
7153
7154
7155
7156
7157 <span style="font-style: italic;">output quan-</span><br style="font-style: italic;">
7158
7159
7160
7161
7162
7163
7164 <span style="font-style: italic;">tities</span><br>
7165
7166
7167
7168
7169
7170
7171 </td>
7172
7173
7174
7175
7176
7177
7178
7179      <td style="vertical-align: top;">Defines the accuracy of
7180the NetCDF output.<br>
7181
7182
7183
7184
7185
7186
7187 <br>
7188
7189
7190
7191
7192
7193
7194
7195By default, all NetCDF output data (see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
7196have single precision&nbsp; (4 byte) accuracy. Double precision (8
7197byte) can be choosen alternatively.<br>
7198
7199
7200
7201
7202
7203
7204
7205Accuracy for the different output data (cross sections, 3d-volume data,
7206spectra, etc.) can be set independently.<br>
7207
7208
7209
7210
7211
7212
7213 <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL4'</span>
7214(single precision) or <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL8'</span>
7215(double precision) are the two principally allowed values for <span style="font-weight: bold;">netcdf_precision</span>,
7216where the string <span style="font-style: italic;">'&lt;out&gt;'
7217      </span>can be chosen out of the following list:<br>
7218
7219
7220
7221
7222
7223
7224 <br>
7225
7226
7227
7228
7229
7230
7231
7232     
7233     
7234     
7235     
7236     
7237     
7238      <table style="text-align: left; width: 284px; height: 234px;" border="1" cellpadding="2" cellspacing="2">
7239
7240
7241
7242
7243
7244
7245 <tbody>
7246
7247
7248
7249
7250
7251
7252
7253          <tr>
7254
7255
7256
7257
7258
7259
7260 <td style="vertical-align: top;"><span style="font-style: italic;">'xy'</span><br>
7261
7262
7263
7264
7265
7266
7267 </td>
7268
7269
7270
7271
7272
7273
7274
7275            <td style="vertical-align: top;">horizontal cross section<br>
7276
7277
7278
7279
7280
7281
7282
7283            </td>
7284
7285
7286
7287
7288
7289
7290 </tr>
7291
7292
7293
7294
7295
7296
7297 <tr>
7298
7299
7300
7301
7302
7303
7304 <td style="vertical-align: top;"><span style="font-style: italic;">'xz'</span><br>
7305
7306
7307
7308
7309
7310
7311 </td>
7312
7313
7314
7315
7316
7317
7318
7319            <td style="vertical-align: top;">vertical (xz) cross
7320section<br>
7321
7322
7323
7324
7325
7326
7327 </td>
7328
7329
7330
7331
7332
7333
7334 </tr>
7335
7336
7337
7338
7339
7340
7341 <tr>
7342
7343
7344
7345
7346
7347
7348 <td style="vertical-align: top;"><span style="font-style: italic;">'yz'</span><br>
7349
7350
7351
7352
7353
7354
7355 </td>
7356
7357
7358
7359
7360
7361
7362
7363            <td style="vertical-align: top;">vertical (yz) cross
7364section<br>
7365
7366
7367
7368
7369
7370
7371 </td>
7372
7373
7374
7375
7376
7377
7378 </tr>
7379
7380
7381
7382
7383
7384
7385 <tr>
7386
7387
7388
7389
7390
7391
7392 <td style="vertical-align: top;"><span style="font-style: italic;">'2d'</span><br>
7393
7394
7395
7396
7397
7398
7399 </td>
7400
7401
7402
7403
7404
7405
7406
7407            <td style="vertical-align: top;">all cross sections<br>
7408
7409
7410
7411
7412
7413
7414
7415            </td>
7416
7417
7418
7419
7420
7421
7422 </tr>
7423
7424
7425
7426
7427
7428
7429 <tr>
7430
7431
7432
7433
7434
7435
7436 <td style="vertical-align: top;"><span style="font-style: italic;">'3d'</span><br>
7437
7438
7439
7440
7441
7442
7443 </td>
7444
7445
7446
7447
7448
7449
7450
7451            <td style="vertical-align: top;">volume data<br>
7452
7453
7454
7455
7456
7457
7458 </td>
7459
7460
7461
7462
7463
7464
7465
7466          </tr>
7467
7468
7469
7470
7471
7472
7473 <tr>
7474
7475
7476
7477
7478
7479
7480 <td style="vertical-align: top;"><span style="font-style: italic;">'pr'</span><br>
7481
7482
7483
7484
7485
7486
7487 </td>
7488
7489
7490
7491
7492
7493
7494
7495            <td style="vertical-align: top;">vertical profiles<br>
7496
7497
7498
7499
7500
7501
7502
7503            </td>
7504
7505
7506
7507
7508
7509
7510 </tr>
7511
7512
7513
7514
7515
7516
7517 <tr>
7518
7519
7520
7521
7522
7523
7524 <td style="vertical-align: top;"><span style="font-style: italic;">'ts'</span><br>
7525
7526
7527
7528
7529
7530
7531 </td>
7532
7533
7534
7535
7536
7537
7538
7539            <td style="vertical-align: top;">time series, particle
7540time series<br>
7541
7542
7543
7544
7545
7546
7547 </td>
7548
7549
7550
7551
7552
7553
7554 </tr>
7555
7556
7557
7558
7559
7560
7561 <tr>
7562
7563
7564
7565
7566
7567
7568 <td style="vertical-align: top;"><span style="font-style: italic;">'sp'</span><br>
7569
7570
7571
7572
7573
7574
7575 </td>
7576
7577
7578
7579
7580
7581
7582
7583            <td style="vertical-align: top;">spectra<br>
7584
7585
7586
7587
7588
7589
7590 </td>
7591
7592
7593
7594
7595
7596
7597
7598          </tr>
7599
7600
7601
7602
7603
7604
7605 <tr>
7606
7607
7608
7609
7610
7611
7612 <td style="vertical-align: top;"><span style="font-style: italic;">'prt'</span><br>
7613
7614
7615
7616
7617
7618
7619 </td>
7620
7621
7622
7623
7624
7625
7626
7627            <td style="vertical-align: top;">particles<br>
7628
7629
7630
7631
7632
7633
7634 </td>
7635
7636
7637
7638
7639
7640
7641
7642          </tr>
7643
7644
7645
7646
7647
7648
7649 <tr>
7650
7651
7652
7653
7654
7655
7656 <td style="vertical-align: top;"><span style="font-style: italic;">'all'</span><br>
7657
7658
7659
7660
7661
7662
7663 </td>
7664
7665
7666
7667
7668
7669
7670
7671            <td style="vertical-align: top;">all output quantities<br>
7672
7673
7674
7675
7676
7677
7678
7679            </td>
7680
7681
7682
7683
7684
7685
7686 </tr>
7687
7688
7689
7690
7691
7692
7693 
7694       
7695       
7696       
7697       
7698       
7699       
7700        </tbody> 
7701     
7702     
7703     
7704     
7705     
7706     
7707      </table>
7708
7709
7710
7711
7712
7713
7714 <br>
7715
7716
7717
7718
7719
7720
7721 <span style="font-weight: bold;">Example:</span><br>
7722
7723
7724
7725
7726
7727
7728
7729If all cross section data and the particle data shall be output in
7730double 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>
7731has to be assigned.<br>
7732
7733
7734
7735
7736
7737
7738 </td>
7739
7740
7741
7742
7743
7744
7745 </tr>
7746
7747
7748
7749
7750
7751
7752
7753   
7754
7755
7756
7757
7758
7759
7760 
7761
7762
7763
7764
7765
7766
7767
7768    <tr>
7769
7770
7771
7772
7773
7774
7775 <td style="vertical-align: top;"> 
7776     
7777     
7778     
7779     
7780     
7781     
7782      <p><a name="nsor_ini"></a><b>nsor_ini</b></p>
7783
7784
7785
7786
7787
7788
7789
7790      </td>
7791
7792
7793
7794
7795
7796
7797 <td style="vertical-align: top;">I</td>
7798
7799
7800
7801
7802
7803
7804
7805      <td style="vertical-align: top;"><i>100</i></td>
7806
7807
7808
7809
7810
7811
7812
7813      <td style="vertical-align: top;"> 
7814     
7815     
7816     
7817     
7818     
7819     
7820      <p>Initial number
7821of iterations with the SOR algorithm.&nbsp; </p>
7822
7823
7824
7825
7826
7827
7828 
7829     
7830     
7831     
7832     
7833     
7834     
7835      <p>This
7836parameter is only effective if the SOR algorithm was
7837selected as the pressure solver scheme (<a href="chapter_4.2.html#psolver">psolver</a>
7838= <span style="font-style: italic;">'sor'</span>)
7839and specifies the
7840number of initial iterations of the SOR
7841scheme (at t = 0). The number of subsequent iterations at the following
7842timesteps is determined
7843with the parameter <a href="#nsor">nsor</a>.
7844Usually <b>nsor</b> &lt; <b>nsor_ini</b>,
7845since in each case
7846subsequent calls to <a href="chapter_4.2.html#psolver">psolver</a>
7847use the solution of the previous call as initial value. Suitable
7848test runs should determine whether sufficient convergence of the
7849solution is obtained with the default value and if necessary the value
7850of <b>nsor_ini</b> should be changed.</p>
7851
7852
7853
7854
7855
7856
7857 </td>
7858
7859
7860
7861
7862
7863
7864
7865    </tr>
7866
7867
7868
7869
7870
7871
7872 <tr>
7873
7874
7875
7876
7877
7878
7879 <td style="vertical-align: top;">
7880     
7881     
7882     
7883     
7884     
7885     
7886      <p><a name="nx"></a><b>nx</b></p>
7887
7888
7889
7890
7891
7892
7893
7894      </td>
7895
7896
7897
7898
7899
7900
7901 <td style="vertical-align: top;">I</td>
7902
7903
7904
7905
7906
7907
7908
7909      <td style="vertical-align: top;"><br>
7910
7911
7912
7913
7914
7915
7916 </td>
7917
7918
7919
7920
7921
7922
7923 <td style="vertical-align: top;"> 
7924     
7925     
7926     
7927     
7928     
7929     
7930      <p>Number of grid
7931points in x-direction.&nbsp; </p>
7932
7933
7934
7935
7936
7937
7938 
7939     
7940     
7941     
7942     
7943     
7944     
7945      <p>A value for this
7946parameter must be assigned. Since the lower
7947array bound in PALM
7948starts with i = 0, the actual number of grid points is equal to <b>nx+1</b>.
7949In case of cyclic boundary conditions along x, the domain size is (<b>nx+1</b>)*
7950      <a href="#dx">dx</a>.</p>
7951
7952
7953
7954
7955
7956
7957 
7958     
7959     
7960     
7961     
7962     
7963     
7964      <p>For
7965parallel runs, in case of <a href="#grid_matching">grid_matching</a>
7966= <span style="font-style: italic;">'strict'</span>,
7967      <b>nx+1</b> must
7968be an integral multiple
7969of the processor numbers (see <a href="#npex">npex</a>
7970and <a href="#npey">npey</a>)
7971along x- as well as along y-direction (due to data
7972transposition restrictions).</p>
7973
7974
7975
7976
7977
7978
7979     
7980     
7981     
7982     
7983     
7984     
7985      <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>
7986and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
7987
7988
7989
7990
7991
7992
7993 </td>
7994
7995
7996
7997
7998
7999
8000 </tr>
8001
8002
8003
8004
8005
8006
8007 <tr>
8008
8009
8010
8011
8012
8013
8014
8015      <td style="vertical-align: top;"> 
8016     
8017     
8018     
8019     
8020     
8021     
8022      <p><a name="ny"></a><b>ny</b></p>
8023
8024
8025
8026
8027
8028
8029
8030      </td>
8031
8032
8033
8034
8035
8036
8037 <td style="vertical-align: top;">I</td>
8038
8039
8040
8041
8042
8043
8044
8045      <td style="vertical-align: top;"><br>
8046
8047
8048
8049
8050
8051
8052 </td>
8053
8054
8055
8056
8057
8058
8059 <td style="vertical-align: top;"> 
8060     
8061     
8062     
8063     
8064     
8065     
8066      <p>Number of grid
8067points in y-direction.&nbsp; </p>
8068
8069
8070
8071
8072
8073
8074 
8075     
8076     
8077     
8078     
8079     
8080     
8081      <p>A value for this
8082parameter must be assigned. Since the lower
8083array bound in PALM starts with j = 0, the actual number of grid points
8084is equal to <b>ny+1</b>. In case of cyclic boundary
8085conditions along
8086y, the domain size is (<b>ny+1</b>) * <a href="#dy">dy</a>.</p>
8087
8088
8089
8090
8091
8092
8093
8094     
8095     
8096     
8097     
8098     
8099     
8100      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8101= <span style="font-style: italic;">'strict'</span>,
8102      <b>ny+1</b> must
8103be an integral multiple
8104of the processor numbers (see <a href="#npex">npex</a>
8105and <a href="#npey">npey</a>)&nbsp;
8106along y- as well as along x-direction (due to data
8107transposition restrictions).</p>
8108
8109
8110
8111
8112
8113
8114     
8115     
8116     
8117     
8118     
8119     
8120      <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>
8121and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8122
8123
8124
8125
8126
8127
8128 </td>
8129
8130
8131
8132
8133
8134
8135 </tr>
8136
8137
8138
8139
8140
8141
8142 <tr>
8143
8144
8145
8146
8147
8148
8149
8150      <td style="vertical-align: top;"> 
8151     
8152     
8153     
8154     
8155     
8156     
8157      <p><a name="nz"></a><b>nz</b></p>
8158
8159
8160
8161
8162
8163
8164
8165      </td>
8166
8167
8168
8169
8170
8171
8172 <td style="vertical-align: top;">I</td>
8173
8174
8175
8176
8177
8178
8179
8180      <td style="vertical-align: top;"><br>
8181
8182
8183
8184
8185
8186
8187 </td>
8188
8189
8190
8191
8192
8193
8194 <td style="vertical-align: top;"> 
8195     
8196     
8197     
8198     
8199     
8200     
8201      <p>Number of grid
8202points in z-direction.&nbsp; </p>
8203
8204
8205
8206
8207
8208
8209 
8210     
8211     
8212     
8213     
8214     
8215     
8216      <p>A value for this
8217parameter must be assigned. Since the lower
8218array bound in PALM
8219starts with k = 0 and since one additional grid point is added at the
8220top boundary (k = <b>nz+1</b>), the actual number of grid
8221points is <b>nz+2</b>.
8222However, the prognostic equations are only solved up to <b>nz</b>
8223(u,
8224v)
8225or up to <b>nz-1</b> (w, scalar quantities). The top
8226boundary for u
8227and v is at k = <b>nz+1</b> (u, v) while at k = <b>nz</b>
8228for all
8229other quantities.&nbsp; </p>
8230
8231
8232
8233
8234
8235
8236 
8237     
8238     
8239     
8240     
8241     
8242     
8243      <p>For parallel
8244runs,&nbsp; in case of <a href="#grid_matching">grid_matching</a>
8245= <span style="font-style: italic;">'strict'</span>,
8246      <b>nz</b> must
8247be an integral multiple of
8248the number of processors in x-direction (due to data transposition
8249restrictions).</p>
8250
8251
8252
8253
8254
8255
8256 </td>
8257
8258
8259
8260
8261
8262
8263 </tr>
8264
8265
8266
8267
8268
8269
8270 <tr>
8271
8272
8273
8274
8275
8276
8277      <td style="vertical-align: top;"><a name="ocean"></a><span style="font-weight: bold;">ocean</span></td>
8278
8279
8280
8281
8282
8283
8284      <td style="vertical-align: top;">L</td>
8285
8286
8287
8288
8289
8290
8291      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
8292
8293
8294
8295
8296
8297
8298      <td style="vertical-align: top;">Parameter to switch on&nbsp;ocean runs.<br>
8299
8300
8301
8302
8303
8304
8305      <br>
8306
8307
8308
8309
8310
8311
8312By 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>
8313
8314
8315
8316
8317
8318
8319      <br>
8320
8321
8322
8323
8324
8325
8326     
8327     
8328     
8329     
8330     
8331     
8332      <ul>
8333
8334
8335
8336
8337
8338
8339        <li>An additional prognostic equation for salinity is solved.</li>
8340
8341
8342
8343
8344
8345
8346        <li>Potential temperature in buoyancy and stability-related terms is replaced by potential density.</li>
8347
8348
8349
8350
8351
8352
8353        <li>Potential
8354density is calculated from the equation of state for seawater after
8355each timestep, using the algorithm proposed by Jackett et al. (2006, J.
8356Atmos. Oceanic Technol., <span style="font-weight: bold;">23</span>, 1709-1728).<br>
8357
8358
8359
8360
8361
8362
8363So far, only the initial hydrostatic pressure is entered into this equation.</li>
8364
8365
8366
8367
8368
8369
8370        <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>
8371
8372
8373
8374
8375
8376
8377        <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>
8378
8379
8380
8381
8382
8383
8384        <li>Zero salinity flux is used as default boundary condition at the bottom of the sea.</li>
8385
8386
8387
8388
8389
8390
8391        <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>
8392
8393
8394
8395
8396
8397
8398     
8399     
8400     
8401     
8402     
8403     
8404      </ul>
8405
8406
8407
8408
8409
8410
8411      <br>
8412
8413
8414
8415
8416
8417
8418Relevant 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>
8419
8420
8421
8422
8423
8424
8425      <br>
8426
8427
8428
8429
8430
8431
8432Section <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>
8433
8434
8435
8436
8437
8438
8439      <br>
8440
8441
8442
8443
8444
8445
8446      <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>
8447
8448
8449
8450      </td>
8451
8452
8453
8454
8455
8456
8457    </tr>
8458
8459
8460
8461
8462
8463
8464    <tr>
8465
8466
8467
8468
8469
8470
8471 <td style="vertical-align: top;"> 
8472     
8473     
8474     
8475     
8476     
8477     
8478      <p><a name="omega"></a><b>omega</b></p>
8479
8480
8481
8482
8483
8484
8485
8486      </td>
8487
8488
8489
8490
8491
8492
8493 <td style="vertical-align: top;">R</td>
8494
8495
8496
8497
8498
8499
8500
8501      <td style="vertical-align: top;"><i>7.29212E-5</i></td>
8502
8503
8504
8505
8506
8507
8508
8509      <td style="vertical-align: top;"> 
8510     
8511     
8512     
8513     
8514     
8515     
8516      <p>Angular
8517velocity of the rotating system (in rad s<sup>-1</sup>).&nbsp;
8518      </p>
8519
8520
8521
8522
8523
8524
8525 
8526     
8527     
8528     
8529     
8530     
8531     
8532      <p>The angular velocity of the earth is set by
8533default. The
8534values
8535of the Coriolis parameters are calculated as:&nbsp; </p>
8536
8537
8538
8539
8540
8541
8542 
8543     
8544     
8545     
8546     
8547     
8548     
8549      <ul>
8550
8551
8552
8553
8554
8555
8556
8557       
8558       
8559       
8560       
8561       
8562       
8563        <p>f = 2.0 * <b>omega</b> * sin(<a href="#phi">phi</a>)&nbsp;
8564        <br>
8565
8566
8567
8568
8569
8570
8571f* = 2.0 * <b>omega</b> * cos(<a href="#phi">phi</a>)</p>
8572
8573
8574
8575
8576
8577
8578
8579     
8580     
8581     
8582     
8583     
8584     
8585      </ul>
8586
8587
8588
8589
8590
8591
8592 </td>
8593
8594
8595
8596
8597
8598
8599 </tr>
8600
8601
8602
8603
8604
8605
8606 <tr>
8607
8608
8609
8610
8611
8612
8613 <td style="vertical-align: top;"> 
8614     
8615     
8616     
8617     
8618     
8619     
8620      <p><a name="outflow_damping_width"></a><b>outflow_damping_width</b></p>
8621
8622
8623
8624
8625
8626
8627
8628      </td>
8629
8630
8631
8632
8633
8634
8635 <td style="vertical-align: top;">I</td>
8636
8637
8638
8639
8640
8641
8642
8643      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(20,
8644nx/2</span> or <span style="font-style: italic;">ny/2)</span></td>
8645
8646
8647
8648
8649
8650
8651
8652      <td style="vertical-align: top;">Width of
8653the damping range in the vicinity of the outflow (gridpoints).<br>
8654
8655
8656
8657
8658
8659
8660
8661      <br>
8662
8663
8664
8665
8666
8667
8668
8669When using non-cyclic lateral boundaries (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
8670or <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
8671a smoothing has to be applied to the
8672velocity field in the vicinity of the outflow in order to suppress any
8673reflections of outgoing disturbances. This parameter controlls the
8674horizontal range to which the smoothing is applied. The range is given
8675in gridpoints counted from the respective outflow boundary. For further
8676details about the smoothing see parameter <a href="chapter_4.1.html#km_damp_max">km_damp_max</a>,
8677which defines the magnitude of the damping.</td>
8678
8679
8680
8681
8682
8683
8684 </tr>
8685
8686
8687
8688
8689
8690
8691
8692    <tr>
8693
8694
8695
8696
8697
8698
8699 <td style="vertical-align: top;"> 
8700     
8701     
8702     
8703     
8704     
8705     
8706      <p><a name="overshoot_limit_e"></a><b>overshoot_limit_e</b></p>
8707
8708
8709
8710
8711
8712
8713
8714      </td>
8715
8716
8717
8718
8719
8720
8721 <td style="vertical-align: top;">R</td>
8722
8723
8724
8725
8726
8727
8728
8729      <td style="vertical-align: top;"><i>0.0</i></td>
8730
8731
8732
8733
8734
8735
8736
8737      <td style="vertical-align: top;"> 
8738     
8739     
8740     
8741     
8742     
8743     
8744      <p>Allowed limit
8745for the overshooting of subgrid-scale TKE in
8746case that the upstream-spline scheme is switched on (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
8747      </p>
8748
8749
8750
8751
8752
8753
8754 
8755     
8756     
8757     
8758     
8759     
8760     
8761      <p>By deafult, if cut-off of overshoots is switched
8762on for the
8763upstream-spline scheme (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>),
8764no overshoots are permitted at all. If <b>overshoot_limit_e</b>
8765is given a non-zero value, overshoots with the respective
8766amplitude (both upward and downward) are allowed.&nbsp; </p>
8767
8768
8769
8770
8771
8772
8773
8774     
8775     
8776     
8777     
8778     
8779     
8780      <p>Only positive values are allowed for <b>overshoot_limit_e</b>.</p>
8781
8782
8783
8784
8785
8786
8787
8788      </td>
8789
8790
8791
8792
8793
8794
8795 </tr>
8796
8797
8798
8799
8800
8801
8802 <tr>
8803
8804
8805
8806
8807
8808
8809 <td style="vertical-align: top;"> 
8810     
8811     
8812     
8813     
8814     
8815     
8816      <p><a name="overshoot_limit_pt"></a><b>overshoot_limit_pt</b></p>
8817
8818
8819
8820
8821
8822
8823
8824      </td>
8825
8826
8827
8828
8829
8830
8831 <td style="vertical-align: top;">R</td>
8832
8833
8834
8835
8836
8837
8838
8839      <td style="vertical-align: top;"><i>0.0</i></td>
8840
8841
8842
8843
8844
8845
8846
8847      <td style="vertical-align: top;"> 
8848     
8849     
8850     
8851     
8852     
8853     
8854      <p>Allowed limit
8855for the overshooting of potential temperature in
8856case that the upstream-spline scheme is switched on (in K).&nbsp; </p>
8857
8858
8859
8860
8861
8862
8863
8864     
8865     
8866     
8867     
8868     
8869     
8870      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
8871      </p>
8872
8873
8874
8875
8876
8877
8878 
8879     
8880     
8881     
8882     
8883     
8884     
8885      <p>Only positive values are allowed for <b>overshoot_limit_pt</b>.</p>
8886
8887
8888
8889
8890
8891
8892
8893      </td>
8894
8895
8896
8897
8898
8899
8900 </tr>
8901
8902
8903
8904
8905
8906
8907 <tr>
8908
8909
8910
8911
8912
8913
8914 <td style="vertical-align: top;"> 
8915     
8916     
8917     
8918     
8919     
8920     
8921      <p><a name="overshoot_limit_u"></a><b>overshoot_limit_u</b></p>
8922
8923
8924
8925
8926
8927
8928
8929      </td>
8930
8931
8932
8933
8934
8935
8936 <td style="vertical-align: top;">R</td>
8937
8938
8939
8940
8941
8942
8943
8944      <td style="vertical-align: top;"><i>0.0</i></td>
8945
8946
8947
8948
8949
8950
8951
8952      <td style="vertical-align: top;">Allowed limit for the
8953overshooting of
8954the u-component of velocity in case that the upstream-spline scheme is
8955switched on (in m/s).
8956     
8957     
8958     
8959     
8960     
8961     
8962      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
8963      </p>
8964
8965
8966
8967
8968
8969
8970 
8971     
8972     
8973     
8974     
8975     
8976     
8977      <p>Only positive values are allowed for <b>overshoot_limit_u</b>.</p>
8978
8979
8980
8981
8982
8983
8984
8985      </td>
8986
8987
8988
8989
8990
8991
8992 </tr>
8993
8994
8995
8996
8997
8998
8999 <tr>
9000
9001
9002
9003
9004
9005
9006 <td style="vertical-align: top;"> 
9007     
9008     
9009     
9010     
9011     
9012     
9013      <p><a name="overshoot_limit_v"></a><b>overshoot_limit_v</b></p>
9014
9015
9016
9017
9018
9019
9020
9021      </td>
9022
9023
9024
9025
9026
9027
9028 <td style="vertical-align: top;">R</td>
9029
9030
9031
9032
9033
9034
9035
9036      <td style="vertical-align: top;"><i>0.0</i></td>
9037
9038
9039
9040
9041
9042
9043
9044      <td style="vertical-align: top;"> 
9045     
9046     
9047     
9048     
9049     
9050     
9051      <p>Allowed limit
9052for the overshooting of the v-component of
9053velocity in case that the upstream-spline scheme is switched on
9054(in m/s).&nbsp; </p>
9055
9056
9057
9058
9059
9060
9061 
9062     
9063     
9064     
9065     
9066     
9067     
9068      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9069      </p>
9070
9071
9072
9073
9074
9075
9076 
9077     
9078     
9079     
9080     
9081     
9082     
9083      <p>Only positive values are allowed for <b>overshoot_limit_v</b>.</p>
9084
9085
9086
9087
9088
9089
9090
9091      </td>
9092
9093
9094
9095
9096
9097
9098 </tr>
9099
9100
9101
9102
9103
9104
9105 <tr>
9106
9107
9108
9109
9110
9111
9112 <td style="vertical-align: top;"> 
9113     
9114     
9115     
9116     
9117     
9118     
9119      <p><a name="overshoot_limit_w"></a><b>overshoot_limit_w</b></p>
9120
9121
9122
9123
9124
9125
9126
9127      </td>
9128
9129
9130
9131
9132
9133
9134 <td style="vertical-align: top;">R</td>
9135
9136
9137
9138
9139
9140
9141
9142      <td style="vertical-align: top;"><i>0.0</i></td>
9143
9144
9145
9146
9147
9148
9149
9150      <td style="vertical-align: top;"> 
9151     
9152     
9153     
9154     
9155     
9156     
9157      <p>Allowed limit
9158for the overshooting of the w-component of
9159velocity in case that the upstream-spline scheme is switched on
9160(in m/s).&nbsp; </p>
9161
9162
9163
9164
9165
9166
9167 
9168     
9169     
9170     
9171     
9172     
9173     
9174      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9175      </p>
9176
9177
9178
9179
9180
9181
9182 
9183     
9184     
9185     
9186     
9187     
9188     
9189      <p>Only positive values are permitted for <b>overshoot_limit_w</b>.</p>
9190
9191
9192
9193
9194
9195
9196
9197      </td>
9198
9199
9200
9201
9202
9203
9204 </tr>
9205
9206
9207
9208
9209
9210
9211 <tr>
9212
9213
9214
9215
9216
9217
9218 <td style="vertical-align: top;"> 
9219     
9220     
9221     
9222     
9223     
9224     
9225      <p><a name="passive_scalar"></a><b>passive_scalar</b></p>
9226
9227
9228
9229
9230
9231
9232
9233      </td>
9234
9235
9236
9237
9238
9239
9240 <td style="vertical-align: top;">L</td>
9241
9242
9243
9244
9245
9246
9247
9248      <td style="vertical-align: top;"><i>.F.</i></td>
9249
9250
9251
9252
9253
9254
9255
9256      <td style="vertical-align: top;"> 
9257     
9258     
9259     
9260     
9261     
9262     
9263      <p>Parameter to
9264switch on the prognostic equation for a passive
9265scalar. <br>
9266
9267
9268
9269
9270
9271
9272 </p>
9273
9274
9275
9276
9277
9278
9279 
9280     
9281     
9282     
9283     
9284     
9285     
9286      <p>The initial vertical profile
9287of s can be set via parameters <a href="#s_surface">s_surface</a>,
9288      <a href="#s_vertical_gradient">s_vertical_gradient</a>
9289and&nbsp; <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.
9290Boundary conditions can be set via <a href="#s_surface_initial_change">s_surface_initial_change</a>
9291and <a href="#surface_scalarflux">surface_scalarflux</a>.&nbsp;
9292      </p>
9293
9294
9295
9296
9297
9298
9299 
9300     
9301     
9302     
9303     
9304     
9305     
9306      <p><b>Note:</b> <br>
9307
9308
9309
9310
9311
9312
9313
9314With <span style="font-weight: bold;">passive_scalar</span>
9315switched
9316on, the simultaneous use of humidity (see&nbsp;<a href="#humidity">humidity</a>)
9317is impossible.</p>
9318
9319
9320
9321
9322
9323
9324 </td>
9325
9326
9327
9328
9329
9330
9331 </tr>
9332
9333
9334
9335
9336
9337
9338 <tr>
9339
9340      <td style="vertical-align: top;"><a name="pch_index"></a><span style="font-weight: bold;">pch_index</span></td>
9341
9342      <td style="vertical-align: top;">I</td>
9343
9344      <td style="vertical-align: top;"><span style="font-style: italic;">0</span></td>
9345
9346      <td style="vertical-align: top;">Grid point index (scalar) of the upper boundary of the plant canopy layer.<br>
9347
9348      <br>
9349
9350Above <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>
9351
9352    </tr>
9353
9354    <tr>
9355
9356
9357
9358
9359
9360
9361 <td style="vertical-align: top;"> 
9362     
9363     
9364     
9365     
9366     
9367     
9368      <p><a name="phi"></a><b>phi</b></p>
9369
9370
9371
9372
9373
9374
9375
9376      </td>
9377
9378
9379
9380
9381
9382
9383 <td style="vertical-align: top;">R</td>
9384
9385
9386
9387
9388
9389
9390
9391      <td style="vertical-align: top;"><i>55.0</i></td>
9392
9393
9394
9395
9396
9397
9398
9399      <td style="vertical-align: top;"> 
9400     
9401     
9402     
9403     
9404     
9405     
9406      <p>Geographical
9407latitude (in degrees).&nbsp; </p>
9408
9409
9410
9411
9412
9413
9414 
9415     
9416     
9417     
9418     
9419     
9420     
9421      <p>The value of
9422this parameter determines the value of the
9423Coriolis parameters f and f*, provided that the angular velocity (see <a href="#omega">omega</a>)
9424is non-zero.</p>
9425
9426
9427
9428
9429
9430
9431 </td>
9432
9433
9434
9435
9436
9437
9438 </tr>
9439
9440
9441
9442
9443
9444
9445 <tr>
9446
9447      <td style="vertical-align: top;"><a name="plant_canopy"></a><span style="font-weight: bold;">plant_canopy</span></td>
9448
9449      <td style="vertical-align: top;">L</td>
9450
9451      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9452
9453      <td style="vertical-align: top;">Switch for the plant_canopy_model.<br>
9454
9455      <br>
9456
9457If <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>
9458
9459The
9460impact of a plant canopy on a turbulent flow is considered by an
9461additional drag term in the momentum equations and an additional sink
9462term in the prognostic equation for the subgrid-scale TKE. These
9463additional 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>). The top boundary of the plant canopy is determined by the parameter