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18  <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1"><title>PALM chapter 4.1</title></head><body>
19
20
21
22
23
24
25<h3><a name="chapter4.1"></a>4.1
26Initialization parameters</h3>
27
28
29
30
31
32
33
34<br>
35
36
37
38
39
40
41<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
42
43
44
45
46
47
48 <tbody>
49
50
51
52
53
54
55
56    <tr>
57
58
59
60
61
62
63 <td style="vertical-align: top;"><font size="4"><b>Parameter name</b></font></td>
64
65
66
67
68
69
70
71      <td style="vertical-align: top;"><font size="4"><b>Type</b></font></td>
72
73
74
75
76
77
78
79      <td style="vertical-align: top;"> 
80     
81     
82     
83     
84     
85     
86      <p><b><font size="4">Default</font></b> <br>
87
88
89
90
91
92
93 <b><font size="4">value</font></b></p>
94
95
96
97
98
99
100 </td>
101
102
103
104
105
106
107
108      <td style="vertical-align: top;"><font size="4"><b>Explanation</b></font></td>
109
110
111
112
113
114
115
116    </tr>
117
118
119
120
121
122
123 <tr>
124
125
126
127
128
129
130 <td style="vertical-align: top;">
131     
132     
133     
134     
135     
136     
137      <p><a name="adjust_mixing_length"></a><b>adjust_mixing_length</b></p>
138
139
140
141
142
143
144
145      </td>
146
147
148
149
150
151
152 <td style="vertical-align: top;">L</td>
153
154
155
156
157
158
159
160      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
161
162
163
164
165
166
167 <td style="vertical-align: top;"> 
168     
169     
170     
171     
172     
173     
174      <p style="font-style: normal;">Near-surface adjustment of the
175mixing length to the Prandtl-layer law.&nbsp; </p>
176
177
178
179
180
181
182 
183     
184     
185     
186     
187     
188     
189      <p>Usually
190the mixing length in LES models l<sub>LES</sub>
191depends (as in PALM) on the grid size and is possibly restricted
192further in case of stable stratification and near the lower wall (see
193parameter <a href="#wall_adjustment">wall_adjustment</a>).
194With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span>
195the Prandtl' mixing length l<sub>PR</sub> = kappa * z/phi
196is calculated
197and the mixing length actually used in the model is set l = MIN (l<sub>LES</sub>,
198l<sub>PR</sub>). This usually gives a decrease of the
199mixing length at
200the bottom boundary and considers the fact that eddy sizes
201decrease in the vicinity of the wall.&nbsp; </p>
202
203
204
205
206
207
208 
209     
210     
211     
212     
213     
214     
215      <p style="font-style: normal;"><b>Warning:</b> So
216far, there is
217no good experience with <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> !&nbsp; </p>
218
219
220
221
222
223
224
225     
226     
227     
228     
229     
230     
231      <p>With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> and the
232Prandtl-layer being
233switched on (see <a href="#prandtl_layer">prandtl_layer</a>)
234      <span style="font-style: italic;">'(u*)** 2+neumann'</span>
235should always be set as the lower boundary condition for the TKE (see <a href="#bc_e_b">bc_e_b</a>),
236otherwise the near-surface value of the TKE is not in agreement with
237the Prandtl-layer law (Prandtl-layer law and Prandtl-Kolmogorov-Ansatz
238should provide the same value for K<sub>m</sub>). A warning
239is given,
240if this is not the case.</p>
241
242
243
244
245
246
247 </td>
248
249
250
251
252
253
254 </tr>
255
256
257
258
259
260
261 <tr>
262
263
264
265
266
267
268
269      <td style="vertical-align: top;"> 
270     
271     
272     
273     
274     
275     
276      <p><a name="alpha_surface"></a><b>alpha_surface</b></p>
277
278
279
280
281
282
283
284      </td>
285
286
287
288
289
290
291 <td style="vertical-align: top;">R<br>
292
293
294
295
296
297
298 </td>
299
300
301
302
303
304
305
306      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
307
308
309
310
311
312
313 </td>
314
315
316
317
318
319
320
321      <td style="vertical-align: top;"> 
322     
323     
324     
325     
326     
327     
328      <p style="font-style: normal;">Inclination of the model domain
329with respect to the horizontal (in degrees).&nbsp; </p>
330
331
332
333
334
335
336 
337     
338     
339     
340     
341     
342     
343      <p style="font-style: normal;">By means of <b>alpha_surface</b>
344the model domain can be inclined in x-direction with respect to the
345horizontal. In this way flows over inclined surfaces (e.g. drainage
346flows, gravity flows) can be simulated. In case of <b>alpha_surface
347      </b>/= <span style="font-style: italic;">0</span>
348the buoyancy term
349appears both in
350the equation of motion of the u-component and of the w-component.<br>
351
352
353
354
355
356
357
358      </p>
359
360
361
362
363
364
365 
366     
367     
368     
369     
370     
371     
372      <p style="font-style: normal;">An inclination
373is only possible in
374case of cyclic horizontal boundary conditions along x AND y (see <a href="#bc_lr">bc_lr</a>
375and <a href="#bc_ns">bc_ns</a>) and <a href="#topography">topography</a> = <span style="font-style: italic;">'flat'</span>. </p>
376
377
378
379
380
381
382
383     
384     
385     
386     
387     
388     
389      <p>Runs with inclined surface still require additional
390user-defined code as well as modifications to the default code. Please
391ask the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/PALM_group.html#0">PALM
392developer&nbsp; group</a>.</p>
393
394
395
396
397
398
399 </td>
400
401
402
403
404
405
406 </tr>
407
408
409
410
411
412
413
414    <tr>
415
416
417
418
419
420
421 <td style="vertical-align: top;"> 
422     
423     
424     
425     
426     
427     
428      <p><a name="bc_e_b"></a><b>bc_e_b</b></p>
429
430
431
432
433
434
435 </td>
436
437
438
439
440
441
442
443      <td style="vertical-align: top;">C * 20</td>
444
445
446
447
448
449
450 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
451
452
453
454
455
456
457
458      <td style="vertical-align: top;"> 
459     
460     
461     
462     
463     
464     
465      <p style="font-style: normal;">Bottom boundary condition of the
466TKE.&nbsp; </p>
467
468
469
470
471
472
473 
474     
475     
476     
477     
478     
479     
480      <p><b>bc_e_b</b> may be
481set to&nbsp;<span style="font-style: italic;">'neumann'</span>
482or <span style="font-style: italic;">'(u*) ** 2+neumann'</span>.
483      <b>bc_e_b</b>
484= <span style="font-style: italic;">'neumann'</span>
485yields to
486e(k=0)=e(k=1) (Neumann boundary condition), where e(k=1) is calculated
487via the prognostic TKE equation. Choice of <span style="font-style: italic;">'(u*)**2+neumann'</span>
488also yields to
489e(k=0)=e(k=1), but the TKE at the Prandtl-layer top (k=1) is calculated
490diagnostically by e(k=1)=(us/0.1)**2. However, this is only allowed if
491a Prandtl-layer is used (<a href="#prandtl_layer">prandtl_layer</a>).
492If this is not the case, a warning is given and <b>bc_e_b</b>
493is reset
494to <span style="font-style: italic;">'neumann'</span>.&nbsp;
495      </p>
496
497
498
499
500
501
502 
503     
504     
505     
506     
507     
508     
509      <p style="font-style: normal;">At the top
510boundary a Neumann
511boundary condition is generally used: (e(nz+1) = e(nz)).</p>
512
513
514
515
516
517
518 </td>
519
520
521
522
523
524
525
526    </tr>
527
528
529
530
531
532
533 <tr>
534
535
536
537
538
539
540 <td style="vertical-align: top;">
541     
542     
543     
544     
545     
546     
547      <p><a name="bc_lr"></a><b>bc_lr</b></p>
548
549
550
551
552
553
554
555      </td>
556
557
558
559
560
561
562 <td style="vertical-align: top;">C * 20</td>
563
564
565
566
567
568
569
570      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
571
572
573
574
575
576
577
578      <td style="vertical-align: top;">Boundary
579condition along x (for all quantities).<br>
580
581
582
583
584
585
586 <br>
587
588
589
590
591
592
593
594By default, a cyclic boundary condition is used along x.<br>
595
596
597
598
599
600
601 <br>
602
603
604
605
606
607
608
609      <span style="font-weight: bold;">bc_lr</span> may
610also be
611assigned the values <span style="font-style: italic;">'dirichlet/radiation'</span>
612(inflow from left, outflow to the right) or <span style="font-style: italic;">'radiation/dirichlet'</span>
613(inflow from
614right, outflow to the left). This requires the multi-grid method to be
615used 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>)
616and it also requires cyclic boundary conditions along y (see&nbsp;<a href="#bc_ns">bc_ns</a>).<br>
617
618
619
620
621
622
623 <br>
624
625
626
627
628
629
630
631In case of these non-cyclic lateral boundaries, a Dirichlet condition
632is used at the inflow for all quantities (initial vertical profiles -
633see <a href="#initializing_actions">initializing_actions</a>
634- are fixed during the run) except u, to which a Neumann (zero
635gradient) condition is applied. At the outflow, a radiation condition is used for all velocity components, while a Neumann (zero
636gradient) condition is used for the scalars. For perturbation
637pressure Neumann (zero gradient) conditions are assumed both at the
638inflow and at the outflow.<br>
639
640
641
642
643
644
645 <br>
646
647
648
649
650
651
652
653When using non-cyclic lateral boundaries, a filter is applied to the
654velocity field in the vicinity of the outflow in order to suppress any
655reflections of outgoing disturbances (see <a href="#km_damp_max">km_damp_max</a>
656and <a href="#outflow_damping_width">outflow_damping_width</a>).<br>
657
658
659
660
661
662
663
664      <br>
665
666
667
668
669
670
671
672In order to maintain a turbulent state of the flow, it may be
673neccessary to continuously impose perturbations on the horizontal
674velocity field in the vicinity of the inflow throughout the whole run.
675This 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>.
676The horizontal range to which these perturbations are applied is
677controlled by the parameters <a href="#inflow_disturbance_begin">inflow_disturbance_begin</a>
678and <a href="#inflow_disturbance_end">inflow_disturbance_end</a>.
679The 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>,
680      <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_level_t</a>,
681and <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_amplitude</a>.
682The 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>
683
684
685
686
687
688
689
690      <br>
691
692
693
694
695
696
697
698In 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
699at_all_substeps</a> = .T. should be used.<br>
700
701
702
703
704
705
706 <br>
707
708
709
710
711
712
713 <span style="font-weight: bold;">Note:</span><br>
714
715
716
717
718
719
720
721Using non-cyclic lateral boundaries requires very sensitive adjustments
722of the inflow (vertical profiles) and the bottom boundary conditions,
723e.g. a surface heating should not be applied near the inflow boundary
724because this may significantly disturb the inflow. Please check the
725model results very carefully.</td>
726
727
728
729
730
731
732 </tr>
733
734
735
736
737
738
739 <tr>
740
741
742
743
744
745
746 <td style="vertical-align: top;"> 
747     
748     
749     
750     
751     
752     
753      <p><a name="bc_ns"></a><b>bc_ns</b></p>
754
755
756
757
758
759
760
761      </td>
762
763
764
765
766
767
768 <td style="vertical-align: top;">C * 20</td>
769
770
771
772
773
774
775
776      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
777
778
779
780
781
782
783
784      <td style="vertical-align: top;">Boundary
785condition along y (for all quantities).<br>
786
787
788
789
790
791
792 <br>
793
794
795
796
797
798
799
800By default, a cyclic boundary condition is used along y.<br>
801
802
803
804
805
806
807 <br>
808
809
810
811
812
813
814
815      <span style="font-weight: bold;">bc_ns</span> may
816also be
817assigned the values <span style="font-style: italic;">'dirichlet/radiation'</span>
818(inflow from rear ("north"), outflow to the front ("south")) or <span style="font-style: italic;">'radiation/dirichlet'</span>
819(inflow from front ("south"), outflow to the rear ("north")). This
820requires the multi-grid
821method to be used for solving the Poisson equation for perturbation
822pressure (see <a href="chapter_4.2.html#psolver">psolver</a>)
823and it also requires cyclic boundary conditions along x (see<br>
824
825
826
827
828
829
830 <a href="#bc_lr">bc_lr</a>).<br>
831
832
833
834
835
836
837 <br>
838
839
840
841
842
843
844
845In case of these non-cyclic lateral boundaries, a Dirichlet condition
846is used at the inflow for all quantities (initial vertical profiles -
847see <a href="chapter_4.1.html#initializing_actions">initializing_actions</a>
848- are fixed during the run) except u, to which a Neumann (zero
849gradient) condition is applied. At the outflow, a radiation condition is used for all velocity components, while a Neumann (zero
850gradient) condition is used for the scalars. For perturbation
851pressure Neumann (zero gradient) conditions are assumed both at the
852inflow and at the outflow.<br>
853
854
855
856
857
858
859 <br>
860
861
862
863
864
865
866
867For further details regarding non-cyclic lateral boundary conditions
868see <a href="#bc_lr">bc_lr</a>.</td>
869
870
871
872
873
874
875 </tr>
876
877
878
879
880
881
882
883    <tr>
884
885
886
887
888
889
890 <td style="vertical-align: top;"> 
891     
892     
893     
894     
895     
896     
897      <p><a name="bc_p_b"></a><b>bc_p_b</b></p>
898
899
900
901
902
903
904 </td>
905
906
907
908
909
910
911
912      <td style="vertical-align: top;">C * 20</td>
913
914
915
916
917
918
919 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
920
921
922
923
924
925
926
927      <td style="vertical-align: top;"> 
928     
929     
930     
931     
932     
933     
934      <p style="font-style: normal;">Bottom boundary condition of the
935perturbation pressure.&nbsp; </p>
936
937
938
939
940
941
942 
943     
944     
945     
946     
947     
948     
949      <p>Allowed values
950are <span style="font-style: italic;">'dirichlet'</span>,
951      <span style="font-style: italic;">'neumann'</span>
952and <span style="font-style: italic;">'neumann+inhomo'</span>.&nbsp;
953      <span style="font-style: italic;">'dirichlet'</span>
954sets
955p(k=0)=0.0,&nbsp; <span style="font-style: italic;">'neumann'</span>
956sets p(k=0)=p(k=1). <span style="font-style: italic;">'neumann+inhomo'</span>
957corresponds to an extended Neumann boundary condition where heat flux
958or temperature inhomogeneities near the
959surface (pt(k=1))&nbsp; are additionally regarded (see Shen and
960LeClerc
961(1995, Q.J.R. Meteorol. Soc.,
9621209)). This condition is only permitted with the Prandtl-layer
963switched on (<a href="#prandtl_layer">prandtl_layer</a>),
964otherwise the run is terminated.&nbsp; </p>
965
966
967
968
969
970
971 
972     
973     
974     
975     
976     
977     
978      <p>Since
979at the bottom boundary of the model the vertical
980velocity
981disappears (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>)
982dp/dz = 0 should
983be used, which leaves the vertical component w unchanged when the
984pressure solver is applied. Simultaneous use of the Neumann boundary
985conditions both at the bottom and at the top boundary (<a href="#bc_p_t">bc_p_t</a>)
986usually yields no consistent solution for the perturbation pressure and
987should be avoided.</p>
988
989
990
991
992
993
994 </td>
995
996
997
998
999
1000
1001 </tr>
1002
1003
1004
1005
1006
1007
1008 <tr>
1009
1010
1011
1012
1013
1014
1015 <td style="vertical-align: top;"> 
1016     
1017     
1018     
1019     
1020     
1021     
1022      <p><a name="bc_p_t"></a><b>bc_p_t</b></p>
1023
1024
1025
1026
1027
1028
1029
1030      </td>
1031
1032
1033
1034
1035
1036
1037 <td style="vertical-align: top;">C * 20</td>
1038
1039
1040
1041
1042
1043
1044
1045      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1046
1047
1048
1049
1050
1051
1052
1053      <td style="vertical-align: top;"> 
1054     
1055     
1056     
1057     
1058     
1059     
1060      <p style="font-style: normal;">Top boundary condition of the
1061perturbation pressure.&nbsp; </p>
1062
1063
1064
1065
1066
1067
1068 
1069     
1070     
1071     
1072     
1073     
1074     
1075      <p style="font-style: normal;">Allowed values are <span style="font-style: italic;">'dirichlet'</span>
1076(p(k=nz+1)= 0.0) or <span style="font-style: italic;">'neumann'</span>
1077(p(k=nz+1)=p(k=nz)).&nbsp; </p>
1078
1079
1080
1081
1082
1083
1084 
1085     
1086     
1087     
1088     
1089     
1090     
1091      <p>Simultaneous use
1092of Neumann boundary conditions both at the
1093top and bottom boundary (<a href="#bc_p_b">bc_p_b</a>)
1094usually yields no consistent solution for the perturbation pressure and
1095should be avoided. Since at the bottom boundary the Neumann
1096condition&nbsp; is a good choice (see <a href="#bc_p_b">bc_p_b</a>),
1097a Dirichlet condition should be set at the top boundary.</p>
1098
1099
1100
1101
1102
1103
1104 </td>
1105
1106
1107
1108
1109
1110
1111
1112    </tr>
1113
1114
1115
1116
1117
1118
1119 <tr>
1120
1121
1122
1123
1124
1125
1126 <td style="vertical-align: top;">
1127     
1128     
1129     
1130     
1131     
1132     
1133      <p><a name="bc_pt_b"></a><b>bc_pt_b</b></p>
1134
1135
1136
1137
1138
1139
1140
1141      </td>
1142
1143
1144
1145
1146
1147
1148 <td style="vertical-align: top;">C*20</td>
1149
1150
1151
1152
1153
1154
1155
1156      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1157
1158
1159
1160
1161
1162
1163
1164      <td style="vertical-align: top;"> 
1165     
1166     
1167     
1168     
1169     
1170     
1171      <p style="font-style: normal;">Bottom boundary condition of the
1172potential temperature.&nbsp; </p>
1173
1174
1175
1176
1177
1178
1179 
1180     
1181     
1182     
1183     
1184     
1185     
1186      <p>Allowed values
1187are <span style="font-style: italic;">'dirichlet'</span>
1188(pt(k=0) = const. = <a href="#pt_surface">pt_surface</a>
1189+ <a href="#pt_surface_initial_change">pt_surface_initial_change</a>;
1190the user may change this value during the run using user-defined code)
1191and <span style="font-style: italic;">'neumann'</span>
1192(pt(k=0)=pt(k=1)).&nbsp; <br>
1193
1194
1195
1196
1197
1198
1199
1200When a constant surface sensible heat flux is used (<a href="#surface_heatflux">surface_heatflux</a>), <b>bc_pt_b</b>
1201= <span style="font-style: italic;">'neumann'</span>
1202must be used, because otherwise the resolved scale may contribute to
1203the surface flux so that a constant value cannot be guaranteed.</p>
1204
1205
1206
1207
1208
1209
1210     
1211     
1212     
1213     
1214     
1215     
1216      <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>
1217
1218
1219
1220
1221
1222
1223
1224      </td>
1225
1226
1227
1228
1229
1230
1231 </tr>
1232
1233
1234
1235
1236
1237
1238 <tr>
1239
1240
1241
1242
1243
1244
1245 <td style="vertical-align: top;"> 
1246     
1247     
1248     
1249     
1250     
1251     
1252      <p><a name="pc_pt_t"></a><b>bc_pt_t</b></p>
1253
1254
1255
1256
1257
1258
1259
1260      </td>
1261
1262
1263
1264
1265
1266
1267 <td style="vertical-align: top;">C * 20</td>
1268
1269
1270
1271
1272
1273
1274
1275      <td style="vertical-align: top;"><span style="font-style: italic;">'initial_ gradient'</span></td>
1276
1277
1278
1279
1280
1281
1282
1283      <td style="vertical-align: top;"> 
1284     
1285     
1286     
1287     
1288     
1289     
1290      <p style="font-style: normal;">Top boundary condition of the
1291potential temperature.&nbsp; </p>
1292
1293
1294
1295
1296
1297
1298 
1299     
1300     
1301     
1302     
1303     
1304     
1305      <p>Allowed are the
1306values <span style="font-style: italic;">'dirichlet' </span>(pt(k=nz+1)
1307does not change during the run), <span style="font-style: italic;">'neumann'</span>
1308(pt(k=nz+1)=pt(k=nz)), and <span style="font-style: italic;">'initial_gradient'</span>.
1309With the 'initial_gradient'-condition the value of the temperature
1310gradient at the top is
1311calculated from the initial
1312temperature profile (see <a href="#pt_surface">pt_surface</a>,
1313      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>)
1314by bc_pt_t_val = (pt_init(k=nz+1) -
1315pt_init(k=nz)) / dzu(nz+1).<br>
1316
1317
1318
1319
1320
1321
1322
1323Using this value (assumed constant during the
1324run) the temperature boundary values are calculated as&nbsp; </p>
1325
1326
1327
1328
1329
1330
1331
1332     
1333     
1334     
1335     
1336     
1337     
1338      <ul>
1339
1340
1341
1342
1343
1344
1345 
1346       
1347       
1348       
1349       
1350       
1351       
1352        <p style="font-style: normal;">pt(k=nz+1) =
1353pt(k=nz) +
1354bc_pt_t_val * dzu(nz+1)</p>
1355
1356
1357
1358
1359
1360
1361 
1362     
1363     
1364     
1365     
1366     
1367     
1368      </ul>
1369
1370
1371
1372
1373
1374
1375 
1376     
1377     
1378     
1379     
1380     
1381     
1382      <p style="font-style: normal;">(up to k=nz the prognostic
1383equation for the temperature is solved).<br>
1384
1385
1386
1387
1388
1389
1390
1391When a constant sensible heat flux is used at the top boundary (<a href="chapter_4.1.html#top_heatflux">top_heatflux</a>),
1392      <b>bc_pt_t</b> = <span style="font-style: italic;">'neumann'</span>
1393must be used, because otherwise the resolved scale may contribute to
1394the top flux so that a constant value cannot be guaranteed.</p>
1395
1396
1397
1398
1399
1400
1401 </td>
1402
1403
1404
1405
1406
1407
1408
1409    </tr>
1410
1411
1412
1413
1414
1415
1416 <tr>
1417
1418
1419
1420
1421
1422
1423 <td style="vertical-align: top;">
1424     
1425     
1426     
1427     
1428     
1429     
1430      <p><a name="bc_q_b"></a><b>bc_q_b</b></p>
1431
1432
1433
1434
1435
1436
1437
1438      </td>
1439
1440
1441
1442
1443
1444
1445 <td style="vertical-align: top;">C * 20</td>
1446
1447
1448
1449
1450
1451
1452
1453      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1454
1455
1456
1457
1458
1459
1460
1461      <td style="vertical-align: top;"> 
1462     
1463     
1464     
1465     
1466     
1467     
1468      <p style="font-style: normal;">Bottom boundary condition of the
1469specific humidity / total water content.&nbsp; </p>
1470
1471
1472
1473
1474
1475
1476 
1477     
1478     
1479     
1480     
1481     
1482     
1483      <p>Allowed
1484values are <span style="font-style: italic;">'dirichlet'</span>
1485(q(k=0) = const. = <a href="#q_surface">q_surface</a>
1486+ <a href="#q_surface_initial_change">q_surface_initial_change</a>;
1487the user may change this value during the run using user-defined code)
1488and <span style="font-style: italic;">'neumann'</span>
1489(q(k=0)=q(k=1)).&nbsp; <br>
1490
1491
1492
1493
1494
1495
1496
1497When a constant surface latent heat flux is used (<a href="#surface_waterflux">surface_waterflux</a>), <b>bc_q_b</b>
1498= <span style="font-style: italic;">'neumann'</span>
1499must be used, because otherwise the resolved scale may contribute to
1500the surface flux so that a constant value cannot be guaranteed.</p>
1501
1502
1503
1504
1505
1506
1507
1508      </td>
1509
1510
1511
1512
1513
1514
1515 </tr>
1516
1517
1518
1519
1520
1521
1522 <tr>
1523
1524
1525
1526
1527
1528
1529 <td style="vertical-align: top;"> 
1530     
1531     
1532     
1533     
1534     
1535     
1536      <p><a name="bc_q_t"></a><b>bc_q_t</b></p>
1537
1538
1539
1540
1541
1542
1543
1544      </td>
1545
1546
1547
1548
1549
1550
1551 <td style="vertical-align: top;"><span style="font-style: italic;">C
1552* 20</span></td>
1553
1554
1555
1556
1557
1558
1559 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1560
1561
1562
1563
1564
1565
1566
1567      <td style="vertical-align: top;"> 
1568     
1569     
1570     
1571     
1572     
1573     
1574      <p style="font-style: normal;">Top boundary condition of the
1575specific humidity / total water content.&nbsp; </p>
1576
1577
1578
1579
1580
1581
1582 
1583     
1584     
1585     
1586     
1587     
1588     
1589      <p>Allowed
1590are the values <span style="font-style: italic;">'dirichlet'</span>
1591(q(k=nz) and q(k=nz+1) do
1592not change during the run) and <span style="font-style: italic;">'neumann'</span>.
1593With the Neumann boundary
1594condition the value of the humidity gradient at the top is calculated
1595from the
1596initial humidity profile (see <a href="#q_surface">q_surface</a>,
1597      <a href="#q_vertical_gradient">q_vertical_gradient</a>)
1598by: bc_q_t_val = ( q_init(k=nz) - q_init(k=nz-1)) / dzu(nz).<br>
1599
1600
1601
1602
1603
1604
1605
1606Using this value (assumed constant during the run) the humidity
1607boundary values
1608are calculated as&nbsp; </p>
1609
1610
1611
1612
1613
1614
1615 
1616     
1617     
1618     
1619     
1620     
1621     
1622      <ul>
1623
1624
1625
1626
1627
1628
1629 
1630       
1631       
1632       
1633       
1634       
1635       
1636        <p style="font-style: normal;">q(k=nz+1) =q(k=nz) +
1637bc_q_t_val * dzu(nz+1)</p>
1638
1639
1640
1641
1642
1643
1644 
1645     
1646     
1647     
1648     
1649     
1650     
1651      </ul>
1652
1653
1654
1655
1656
1657
1658 
1659     
1660     
1661     
1662     
1663     
1664     
1665      <p style="font-style: normal;">(up tp k=nz the prognostic
1666equation for q is solved). </p>
1667
1668
1669
1670
1671
1672
1673 </td>
1674
1675
1676
1677
1678
1679
1680 </tr>
1681
1682
1683
1684
1685
1686
1687 <tr>
1688
1689
1690
1691
1692
1693
1694
1695      <td style="vertical-align: top;"> 
1696     
1697     
1698     
1699     
1700     
1701     
1702      <p><a name="bc_s_b"></a><b>bc_s_b</b></p>
1703
1704
1705
1706
1707
1708
1709 </td>
1710
1711
1712
1713
1714
1715
1716
1717      <td style="vertical-align: top;">C * 20</td>
1718
1719
1720
1721
1722
1723
1724 <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1725
1726
1727
1728
1729
1730
1731
1732      <td style="vertical-align: top;"> 
1733     
1734     
1735     
1736     
1737     
1738     
1739      <p style="font-style: normal;">Bottom boundary condition of the
1740scalar concentration.&nbsp; </p>
1741
1742
1743
1744
1745
1746
1747 
1748     
1749     
1750     
1751     
1752     
1753     
1754      <p>Allowed values
1755are <span style="font-style: italic;">'dirichlet'</span>
1756(s(k=0) = const. = <a href="#s_surface">s_surface</a>
1757+ <a href="#s_surface_initial_change">s_surface_initial_change</a>;
1758the user may change this value during the run using user-defined code)
1759and <span style="font-style: italic;">'neumann'</span>
1760(s(k=0) =
1761s(k=1)).&nbsp; <br>
1762
1763
1764
1765
1766
1767
1768
1769When a constant surface concentration flux is used (<a href="#surface_scalarflux">surface_scalarflux</a>), <b>bc_s_b</b>
1770= <span style="font-style: italic;">'neumann'</span>
1771must be used, because otherwise the resolved scale may contribute to
1772the surface flux so that a constant value cannot be guaranteed.</p>
1773
1774
1775
1776
1777
1778
1779
1780      </td>
1781
1782
1783
1784
1785
1786
1787 </tr>
1788
1789
1790
1791
1792
1793
1794 <tr>
1795
1796
1797
1798
1799
1800
1801 <td style="vertical-align: top;"> 
1802     
1803     
1804     
1805     
1806     
1807     
1808      <p><a name="bc_s_t"></a><b>bc_s_t</b></p>
1809
1810
1811
1812
1813
1814
1815
1816      </td>
1817
1818
1819
1820
1821
1822
1823 <td style="vertical-align: top;">C * 20</td>
1824
1825
1826
1827
1828
1829
1830
1831      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1832
1833
1834
1835
1836
1837
1838
1839      <td style="vertical-align: top;"> 
1840     
1841     
1842     
1843     
1844     
1845     
1846      <p style="font-style: normal;">Top boundary condition of the
1847scalar concentration.&nbsp; </p>
1848
1849
1850
1851
1852
1853
1854 
1855     
1856     
1857     
1858     
1859     
1860     
1861      <p>Allowed are the
1862values <span style="font-style: italic;">'dirichlet'</span>
1863(s(k=nz) and s(k=nz+1) do
1864not change during the run) and <span style="font-style: italic;">'neumann'</span>.
1865With the Neumann boundary
1866condition the value of the scalar concentration gradient at the top is
1867calculated
1868from the initial scalar concentration profile (see <a href="#s_surface">s_surface</a>, <a href="#s_vertical_gradient">s_vertical_gradient</a>)
1869by: bc_s_t_val = (s_init(k=nz) - s_init(k=nz-1)) / dzu(nz).<br>
1870
1871
1872
1873
1874
1875
1876
1877Using this value (assumed constant during the run) the concentration
1878boundary values
1879are calculated as </p>
1880
1881
1882
1883
1884
1885
1886 
1887     
1888     
1889     
1890     
1891     
1892     
1893      <ul>
1894
1895
1896
1897
1898
1899
1900 
1901       
1902       
1903       
1904       
1905       
1906       
1907        <p style="font-style: normal;">s(k=nz+1) = s(k=nz) +
1908bc_s_t_val * dzu(nz+1)</p>
1909
1910
1911
1912
1913
1914
1915 
1916     
1917     
1918     
1919     
1920     
1921     
1922      </ul>
1923
1924
1925
1926
1927
1928
1929 
1930     
1931     
1932     
1933     
1934     
1935     
1936      <p style="font-style: normal;">(up to k=nz the prognostic
1937equation for the scalar concentration is
1938solved).</p>
1939
1940
1941
1942
1943
1944
1945 </td>
1946
1947
1948
1949
1950
1951
1952 </tr>
1953
1954
1955
1956
1957
1958
1959 <tr>
1960
1961
1962
1963
1964
1965
1966      <td style="vertical-align: top;"><a name="bc_sa_t"></a><span style="font-weight: bold;">bc_sa_t</span></td>
1967
1968
1969
1970
1971
1972
1973      <td style="vertical-align: top;">C * 20</td>
1974
1975
1976
1977
1978
1979
1980      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1981
1982
1983
1984
1985
1986
1987      <td style="vertical-align: top;">
1988     
1989     
1990     
1991     
1992     
1993     
1994      <p style="font-style: normal;">Top boundary condition of the salinity.&nbsp; </p>
1995
1996
1997
1998
1999
2000
2001 
2002     
2003     
2004     
2005     
2006     
2007     
2008      <p>This parameter only comes into effect for ocean runs (see parameter <a href="#ocean">ocean</a>).</p>
2009
2010
2011
2012
2013
2014
2015     
2016     
2017     
2018     
2019     
2020     
2021      <p style="font-style: normal;">Allowed are the
2022values <span style="font-style: italic;">'dirichlet' </span>(sa(k=nz+1)
2023does not change during the run) and <span style="font-style: italic;">'neumann'</span>
2024(sa(k=nz+1)=sa(k=nz))<span style="font-style: italic;"></span>.&nbsp;<br>
2025
2026
2027
2028
2029
2030
2031      <br>
2032
2033
2034
2035
2036
2037
2038
2039When a constant salinity flux is used at the top boundary (<a href="chapter_4.1.html#top_salinityflux">top_salinityflux</a>),
2040      <b>bc_sa_t</b> = <span style="font-style: italic;">'neumann'</span>
2041must be used, because otherwise the resolved scale may contribute to
2042the top flux so that a constant value cannot be guaranteed.</p>
2043
2044
2045
2046
2047
2048
2049      </td>
2050
2051
2052
2053
2054
2055
2056    </tr>
2057
2058
2059
2060
2061
2062
2063    <tr>
2064
2065
2066
2067
2068
2069
2070 <td style="vertical-align: top;"> 
2071     
2072     
2073     
2074     
2075     
2076     
2077      <p><a name="bc_uv_b"></a><b>bc_uv_b</b></p>
2078
2079
2080
2081
2082
2083
2084
2085      </td>
2086
2087
2088
2089
2090
2091
2092 <td style="vertical-align: top;">C * 20</td>
2093
2094
2095
2096
2097
2098
2099
2100      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2101
2102
2103
2104
2105
2106
2107
2108      <td style="vertical-align: top;"> 
2109     
2110     
2111     
2112     
2113     
2114     
2115      <p style="font-style: normal;">Bottom boundary condition of the
2116horizontal velocity components u and v.&nbsp; </p>
2117
2118
2119
2120
2121
2122
2123 
2124     
2125     
2126     
2127     
2128     
2129     
2130      <p>Allowed
2131values are <span style="font-style: italic;">'dirichlet' </span>and
2132      <span style="font-style: italic;">'neumann'</span>. <b>bc_uv_b</b>
2133= <span style="font-style: italic;">'dirichlet'</span>
2134yields the
2135no-slip condition with u=v=0 at the bottom. Due to the staggered grid
2136u(k=0) and v(k=0) are located at z = - 0,5 * <a href="#dz">dz</a>
2137(below the bottom), while u(k=1) and v(k=1) are located at z = +0,5 *
2138dz. u=v=0 at the bottom is guaranteed using mirror boundary
2139condition:&nbsp; </p>
2140
2141
2142
2143
2144
2145
2146 
2147     
2148     
2149     
2150     
2151     
2152     
2153      <ul>
2154
2155
2156
2157
2158
2159
2160 
2161       
2162       
2163       
2164       
2165       
2166       
2167        <p style="font-style: normal;">u(k=0) = - u(k=1) and v(k=0) = -
2168v(k=1)</p>
2169
2170
2171
2172
2173
2174
2175 
2176     
2177     
2178     
2179     
2180     
2181     
2182      </ul>
2183
2184
2185
2186
2187
2188
2189 
2190     
2191     
2192     
2193     
2194     
2195     
2196      <p style="font-style: normal;">The
2197Neumann boundary condition
2198yields the free-slip condition with u(k=0) = u(k=1) and v(k=0) =
2199v(k=1).
2200With Prandtl - layer switched on (see <a href="#prandtl_layer">prandtl_layer</a>), the free-slip condition is not
2201allowed (otherwise the run will be terminated)<font color="#000000">.</font></p>
2202
2203
2204
2205
2206
2207
2208
2209      </td>
2210
2211
2212
2213
2214
2215
2216 </tr>
2217
2218
2219
2220
2221
2222
2223 <tr>
2224
2225
2226
2227
2228
2229
2230 <td style="vertical-align: top;"> 
2231     
2232     
2233     
2234     
2235     
2236     
2237      <p><a name="bc_uv_t"></a><b>bc_uv_t</b></p>
2238
2239
2240
2241
2242
2243
2244
2245      </td>
2246
2247
2248
2249
2250
2251
2252 <td style="vertical-align: top;">C * 20</td>
2253
2254
2255
2256
2257
2258
2259
2260      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2261
2262
2263
2264
2265
2266
2267
2268      <td style="vertical-align: top;"> 
2269     
2270     
2271     
2272     
2273     
2274     
2275      <p style="font-style: normal;">Top boundary condition of the
2276horizontal velocity components u and v.&nbsp; </p>
2277
2278
2279
2280
2281
2282
2283 
2284     
2285     
2286     
2287     
2288     
2289     
2290      <p>Allowed
2291values are <span style="font-style: italic;">'dirichlet'</span>, <span style="font-style: italic;">'dirichlet_0'</span>
2292and <span style="font-style: italic;">'neumann'</span>.
2293The
2294Dirichlet condition yields u(k=nz+1) = ug(nz+1) and v(k=nz+1) =
2295vg(nz+1),
2296Neumann condition yields the free-slip condition with u(k=nz+1) =
2297u(k=nz) and v(k=nz+1) = v(k=nz) (up to k=nz the prognostic equations
2298for 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) =
2299vg(nz+1) = 0.</p>
2300
2301
2302
2303
2304
2305
2306     
2307     
2308     
2309     
2310     
2311     
2312      <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>
2313
2314
2315
2316
2317
2318
2319 </td>
2320
2321
2322
2323
2324
2325
2326 </tr>
2327
2328
2329
2330
2331
2332
2333 <tr>
2334
2335
2336
2337
2338
2339
2340      <td style="vertical-align: top;"><a name="bottom_salinityflux"></a><span style="font-weight: bold;">bottom_salinityflux</span></td>
2341
2342
2343
2344
2345
2346
2347      <td style="vertical-align: top;">R</td>
2348
2349
2350
2351
2352
2353
2354      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
2355
2356
2357
2358
2359
2360
2361      <td style="vertical-align: top;">
2362     
2363     
2364     
2365     
2366     
2367     
2368      <p>Kinematic salinity flux near the surface (in psu m/s).&nbsp;</p>
2369
2370
2371
2372
2373
2374
2375This parameter only comes into effect for ocean runs (see parameter <a href="chapter_4.1.html#ocean">ocean</a>).
2376     
2377     
2378     
2379     
2380     
2381     
2382      <p>The
2383respective salinity flux value is used
2384as bottom (horizontally homogeneous) boundary condition for the salinity equation. This additionally requires that a Neumann
2385condition must be used for the salinity, which is currently the only available condition.<br>
2386
2387
2388
2389
2390
2391
2392 </p>
2393
2394
2395
2396
2397
2398
2399 </td>
2400
2401
2402
2403
2404
2405
2406    </tr>
2407
2408
2409
2410
2411
2412
2413    <tr>
2414
2415
2416
2417
2418
2419
2420
2421      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_height"></a>building_height</span></td>
2422
2423
2424
2425
2426
2427
2428
2429      <td style="vertical-align: top;">R</td>
2430
2431
2432
2433
2434
2435
2436 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2437
2438
2439
2440
2441
2442
2443 <td>Height
2444of a single building in m.<br>
2445
2446
2447
2448
2449
2450
2451 <br>
2452
2453
2454
2455
2456
2457
2458 <span style="font-weight: bold;">building_height</span> must
2459be less than the height of the model domain. This parameter requires
2460the use of&nbsp;<a href="#topography">topography</a>
2461= <span style="font-style: italic;">'single_building'</span>.</td>
2462
2463
2464
2465
2466
2467
2468
2469    </tr>
2470
2471
2472
2473
2474
2475
2476 <tr>
2477
2478
2479
2480
2481
2482
2483 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_x"></a>building_length_x</span></td>
2484
2485
2486
2487
2488
2489
2490
2491      <td style="vertical-align: top;">R</td>
2492
2493
2494
2495
2496
2497
2498 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2499
2500
2501
2502
2503
2504
2505 <td><span style="font-style: italic;"></span>Width of a single
2506building in m.<br>
2507
2508
2509
2510
2511
2512
2513 <br>
2514
2515
2516
2517
2518
2519
2520
2521Currently, <span style="font-weight: bold;">building_length_x</span>
2522must be at least <span style="font-style: italic;">3
2523*&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>
2524      </span><span style="font-style: italic;">- <a href="#building_wall_left">building_wall_left</a></span>.
2525This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2526= <span style="font-style: italic;">'single_building'</span>.</td>
2527
2528
2529
2530
2531
2532
2533
2534    </tr>
2535
2536
2537
2538
2539
2540
2541 <tr>
2542
2543
2544
2545
2546
2547
2548 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_y"></a>building_length_y</span></td>
2549
2550
2551
2552
2553
2554
2555
2556      <td style="vertical-align: top;">R</td>
2557
2558
2559
2560
2561
2562
2563 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2564
2565
2566
2567
2568
2569
2570 <td>Depth
2571of a single building in m.<br>
2572
2573
2574
2575
2576
2577
2578 <br>
2579
2580
2581
2582
2583
2584
2585
2586Currently, <span style="font-weight: bold;">building_length_y</span>
2587must be at least <span style="font-style: italic;">3
2588*&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
2589the use of&nbsp;<a href="#topography">topography</a>
2590= <span style="font-style: italic;">'single_building'</span>.</td>
2591
2592
2593
2594
2595
2596
2597
2598    </tr>
2599
2600
2601
2602
2603
2604
2605 <tr>
2606
2607
2608
2609
2610
2611
2612 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_left"></a>building_wall_left</span></td>
2613
2614
2615
2616
2617
2618
2619
2620      <td style="vertical-align: top;">R</td>
2621
2622
2623
2624
2625
2626
2627 <td style="vertical-align: top;"><span style="font-style: italic;">building centered in x-direction</span></td>
2628
2629
2630
2631
2632
2633
2634
2635      <td>x-coordinate of the left building wall (distance between the
2636left building wall and the left border of the model domain) in m.<br>
2637
2638
2639
2640
2641
2642
2643
2644      <br>
2645
2646
2647
2648
2649
2650
2651
2652Currently, <span style="font-weight: bold;">building_wall_left</span>
2653must be at least <span style="font-style: italic;">1
2654*&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;
2655- 1 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a></span>.
2656This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2657= <span style="font-style: italic;">'single_building'</span>.<br>
2658
2659
2660
2661
2662
2663
2664
2665      <br>
2666
2667
2668
2669
2670
2671
2672
2673The default value&nbsp;<span style="font-weight: bold;">building_wall_left</span>
2674= <span style="font-style: italic;">( ( <a href="#nx">nx</a>&nbsp;+
26751 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a> ) / 2</span>
2676centers 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>
2677
2678
2679
2680
2681
2682
2683 </tr>
2684
2685
2686
2687
2688
2689
2690 <tr>
2691
2692
2693
2694
2695
2696
2697
2698      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_south"></a>building_wall_south</span></td>
2699
2700
2701
2702
2703
2704
2705
2706      <td style="vertical-align: top;">R</td>
2707
2708
2709
2710
2711
2712
2713 <td style="vertical-align: top;"><span style="font-style: italic;"></span><span style="font-style: italic;">building centered in y-direction</span></td>
2714
2715
2716
2717
2718
2719
2720
2721      <td>y-coordinate of the South building wall (distance between the
2722South building wall and the South border of the model domain) in m.<br>
2723
2724
2725
2726
2727
2728
2729
2730      <br>
2731
2732
2733
2734
2735
2736
2737
2738Currently, <span style="font-weight: bold;">building_wall_south</span>
2739must be at least <span style="font-style: italic;">1
2740*&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;
2741- 1 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a></span>.
2742This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2743= <span style="font-style: italic;">'single_building'</span>.<br>
2744
2745
2746
2747
2748
2749
2750
2751      <br>
2752
2753
2754
2755
2756
2757
2758
2759The default value&nbsp;<span style="font-weight: bold;">building_wall_south</span>
2760= <span style="font-style: italic;">( ( <a href="#ny">ny</a>&nbsp;+
27611 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a> ) / 2</span>
2762centers 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>
2763
2764
2765
2766
2767
2768
2769 </tr>
2770
2771
2772
2773
2774
2775
2776 <tr>
2777
2778      <td style="vertical-align: top;"><a name="canopy_mode"></a><span style="font-weight: bold;">canopy_mode</span></td>
2779
2780      <td style="vertical-align: top;">C * 20</td>
2781
2782      <td style="vertical-align: top;"><span style="font-style: italic;">'block'</span></td>
2783
2784      <td style="vertical-align: top;">Canopy mode.<br>
2785
2786      <br>
2787
2788      <font color="#000000">
2789Besides using the default value, that will create a horizontally
2790homogeneous plant canopy that extends over the total horizontal
2791extension of the model domain, the user may add code to the user
2792interface subroutine <a href="chapter_3.5.1.html#user_init_plant_canopy">user_init_plant_canopy</a>
2793to allow further canopy&nbsp;modes. <br>
2794
2795      <br>
2796
2797The 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>
2798
2799    </tr>
2800
2801    <tr><td style="font-weight: bold; vertical-align: top;"><a name="canyon_height"></a>canyon_height</td><td style="vertical-align: top;">R</td><td style="font-style: italic; vertical-align: top;">50.0</td><td>Street canyon height
2802in m.<br>
2803
2804
2805
2806
2807
2808
2809 <br>
2810
2811
2812
2813
2814
2815
2816 <span style="font-weight: bold;">canyon_height</span> must
2817be less than the height of the model domain. This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2818= <span style="font-style: italic;">'single_street_canyon'</span>.</td></tr><tr><td style="font-weight: bold; vertical-align: top;"><a name="canyon_width_x"></a>canyon_width_x</td><td style="vertical-align: top;">R</td><td style="font-style: italic; vertical-align: top;">9999999.9</td><td>Street canyon width in x-direction in m.<br>
2819
2820
2821
2822
2823
2824
2825 <br>
2826
2827
2828
2829
2830
2831
2832
2833Currently, <span style="font-weight: bold;">canyon_width_x</span>
2834must be at least <span style="font-style: italic;">3
2835*&nbsp;</span><a style="font-style: italic;" href="chapter_4.1.html#dx">dx</a> and no more than <span style="font-style: italic;">(&nbsp;</span><a style="font-style: italic;" href="chapter_4.1.html#nx">nx</a><span style="font-style: italic;"> - 1 ) </span><span style="font-style: italic;"> * <a href="chapter_4.1.html#dx">dx</a>
2836      </span><span style="font-style: italic;">- <a href="chapter_4.1.html#canyon_wall_left">canyon_wall_left</a></span>.
2837This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2838= <span style="font-style: italic;">'</span><span style="font-style: italic;">single_street_canyon</span><span style="font-style: italic;">'</span>. A non-default value implies a canyon orientation in y-direction.</td></tr><tr><td style="font-weight: bold; vertical-align: top;"><a name="canyon_width_y"></a>canyon_width_y</td><td style="vertical-align: top;">R</td><td style="font-style: italic; vertical-align: top;">9999999.9</td><td>Street canyon width in y-direction in m.<br>
2839
2840
2841
2842
2843
2844
2845 <br>
2846
2847
2848
2849
2850
2851
2852
2853Currently, <span style="font-weight: bold;">canyon_width_y</span>
2854must be at least <span style="font-style: italic;">3
2855*&nbsp;</span><a style="font-style: italic;" href="chapter_4.1.html#dy">dy</a> and no more than <span style="font-style: italic;">(&nbsp;</span><a style="font-style: italic;" href="chapter_4.1.html#ny">ny</a><span style="font-style: italic;"> - 1 )&nbsp;</span><span style="font-style: italic;"> * <a href="chapter_4.1.html#dy">dy</a></span><span style="font-style: italic;"> - <a href="chapter_4.1.html#canyon_wall_south">canyon_wall_south</a></span>. This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2856= <span style="font-style: italic;">'</span><span style="font-style: italic;">single_street_canyon</span>.&nbsp;A non-default value implies a canyon orientation in x-direction.</td></tr><tr><td style="font-weight: bold; vertical-align: top;"><a name="canyon_wall_left"></a>canyon_wall_left</td><td style="vertical-align: top;">R</td><td style="font-style: italic; vertical-align: top;"><span style="font-style: italic;">canyon centered in x-direction</span></td><td>x-coordinate of the left canyon wall (distance between the
2857left canyon wall and the left border of the model domain) in m.<br>
2858
2859
2860
2861
2862
2863
2864
2865      <br>
2866
2867
2868
2869
2870
2871
2872
2873Currently, <span style="font-weight: bold;">canyon_wall_left</span>
2874must be at least <span style="font-style: italic;">1
2875*&nbsp;</span><a style="font-style: italic;" href="chapter_4.1.html#dx">dx</a> and less than <span style="font-style: italic;">( <a href="chapter_4.1.html#nx">nx</a>&nbsp;
2876- 1 ) * <a href="chapter_4.1.html#dx">dx</a> -&nbsp; <a href="chapter_4.1.html#canyon_width_x">canyon_width_x</a></span>.
2877This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2878= <span style="font-style: italic;">'</span><span style="font-style: italic;">single_street_canyon</span><span style="font-style: italic;">'</span>.<br>
2879
2880
2881
2882
2883
2884
2885
2886      <br>
2887
2888
2889
2890
2891
2892
2893
2894The default value <span style="font-weight: bold;">canyon_wall_left</span>
2895= <span style="font-style: italic;">( ( <a href="chapter_4.1.html#nx">nx</a>&nbsp;+
28961 ) * <a href="chapter_4.1.html#dx">dx</a> -&nbsp; <a href="chapter_4.1.html#canyon_width_x">canyon_width_x</a> ) / 2</span>
2897centers the canyon in x-direction.</td></tr><tr><td style="font-weight: bold; vertical-align: top;"><a name="canyon_wall_south"></a>canyon_wall_south</td><td style="vertical-align: top;">R</td><td style="font-style: italic; vertical-align: top;"><span style="font-style: italic;">canyon centered in y-direction</span></td><td>y-coordinate of the South canyon wall (distance between the
2898South canyon wall and the South border of the model domain) in m.<br>
2899
2900
2901
2902
2903
2904
2905
2906      <br>
2907
2908
2909
2910
2911
2912
2913
2914Currently, <span style="font-weight: bold;">canyon_wall_south</span>
2915must be at least <span style="font-style: italic;">1
2916*&nbsp;</span><a style="font-style: italic;" href="chapter_4.1.html#dy">dy</a> and less than <span style="font-style: italic;">( <a href="chapter_4.1.html#ny">ny</a>&nbsp;
2917- 1 ) * <a href="chapter_4.1.html#dy">dy</a> -&nbsp; <a href="chapter_4.1.html#canyon_width_y">canyon_width_y</a></span>.
2918This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2919= <span style="font-style: italic;">'</span><span style="font-style: italic;">single_street_canyon</span><span style="font-style: italic;">'</span>.<br>
2920
2921
2922
2923
2924
2925
2926
2927      <br>
2928
2929
2930
2931
2932
2933
2934
2935The default value <span style="font-weight: bold;">canyon_wall_south</span>
2936= <span style="font-style: italic;">( ( <a href="chapter_4.1.html#ny">ny</a>&nbsp;+
29371 ) * <a href="chapter_4.1.html#dy">dy</a> -&nbsp;&nbsp;</span><a href="chapter_4.1.html#building_length_y"><span style="font-style: italic;"></span></a><a style="font-style: italic;" href="chapter_4.1.html#canyon_width_y">canyon_wid</a><span style="font-style: italic;"><a style="font-style: italic;" href="chapter_4.1.html#canyon_width_y">th_y</a> ) / 2</span>
2938centers the canyon in y-direction.</td></tr><tr>
2939
2940
2941
2942
2943
2944
2945
2946      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="cloud_droplets"></a>cloud_droplets</span><br>
2947
2948
2949
2950
2951
2952
2953
2954      </td>
2955
2956
2957
2958
2959
2960
2961 <td style="vertical-align: top;">L<br>
2962
2963
2964
2965
2966
2967
2968 </td>
2969
2970
2971
2972
2973
2974
2975
2976      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span><br>
2977
2978
2979
2980
2981
2982
2983 </td>
2984
2985
2986
2987
2988
2989
2990
2991      <td style="vertical-align: top;">Parameter to switch on
2992usage of cloud droplets.<br>
2993
2994
2995
2996
2997
2998
2999 <br>
3000
3001
3002
3003
3004
3005
3006
3007      <span style="font-weight: bold;"></span><span style="font-family: monospace;"></span>
3008
3009
3010
3011
3012Cloud 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
3013features (number of droplets, initial radius, etc.) can be steered with
3014the&nbsp; respective particle parameters (see e.g. <a href="#chapter_4.2.html#radius">radius</a>).
3015The real number of initial droplets in a grid cell is equal to the
3016initial 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>
3017      <span lang="en-GB"><font face="Thorndale, serif">and
3018      </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>)
3019times the <a href="#initial_weighting_factor">initial_weighting_factor</a>.<br>
3020
3021
3022
3023
3024
3025
3026
3027      <br>
3028
3029
3030
3031
3032
3033
3034
3035In case of using cloud droplets, the default condensation scheme in
3036PALM cannot be used, i.e. <a href="#cloud_physics">cloud_physics</a>
3037must be set <span style="font-style: italic;">.F.</span>.<br>
3038
3039
3040
3041
3042
3043
3044
3045      </td>
3046
3047
3048
3049
3050
3051
3052 </tr>
3053
3054
3055
3056
3057
3058
3059 <tr>
3060
3061
3062
3063
3064
3065
3066 <td style="vertical-align: top;"> 
3067     
3068     
3069     
3070     
3071     
3072     
3073      <p><a name="cloud_physics"></a><b>cloud_physics</b></p>
3074
3075
3076
3077
3078
3079
3080
3081      </td>
3082
3083
3084
3085
3086
3087
3088 <td style="vertical-align: top;">L<br>
3089
3090
3091
3092
3093
3094
3095 </td>
3096
3097
3098
3099
3100
3101
3102
3103      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
3104
3105
3106
3107
3108
3109
3110 <td style="vertical-align: top;"> 
3111     
3112     
3113     
3114     
3115     
3116     
3117      <p>Parameter to switch
3118on the condensation scheme.&nbsp; </p>
3119
3120
3121
3122
3123
3124
3125
3126For <b>cloud_physics =</b> <span style="font-style: italic;">.TRUE.</span>, equations
3127for the
3128liquid water&nbsp;
3129content and the liquid water potential temperature are solved instead
3130of those for specific humidity and potential temperature. Note
3131that a grid volume is assumed to be either completely saturated or
3132completely
3133unsaturated (0%-or-100%-scheme). A simple precipitation scheme can
3134additionally be switched on with parameter <a href="#precipitation">precipitation</a>.
3135Also cloud-top cooling by longwave radiation can be utilized (see <a href="#radiation">radiation</a>)<br>
3136
3137
3138
3139
3140
3141
3142 <b><br>
3143
3144
3145
3146
3147
3148
3149
3150cloud_physics =</b> <span style="font-style: italic;">.TRUE.
3151      </span>requires&nbsp;<a href="#humidity">humidity</a>
3152=<span style="font-style: italic;"> .TRUE.</span> .<br>
3153
3154
3155
3156
3157
3158
3159
3160Detailed information about the condensation scheme is given in the
3161description of the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM-1/Dokumentationen/Cloud_physics/wolken.pdf">cloud
3162physics module</a> (pdf-file, only in German).<br>
3163
3164
3165
3166
3167
3168
3169 <br>
3170
3171
3172
3173
3174
3175
3176
3177This condensation scheme is not allowed if cloud droplets are simulated
3178explicitly (see <a href="#cloud_droplets">cloud_droplets</a>).<br>
3179
3180
3181
3182
3183
3184
3185
3186      </td>
3187
3188
3189
3190
3191
3192
3193 </tr>
3194
3195
3196
3197
3198
3199
3200 <tr>
3201
3202
3203
3204
3205
3206
3207 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="conserve_volume_flow"></a>conserve_volume_flow</span></td>
3208
3209
3210
3211
3212
3213
3214
3215      <td style="vertical-align: top;">L</td>
3216
3217
3218
3219
3220
3221
3222 <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
3223
3224
3225
3226
3227
3228
3229 <td>Conservation
3230of volume flow in x- and y-direction.<br>
3231
3232
3233
3234
3235
3236
3237 <br>
3238
3239
3240
3241
3242
3243
3244 <span style="font-weight: bold;">conserve_volume_flow</span>
3245= <span style="font-style: italic;">.T.</span>
3246guarantees that the volume flow through the xz- and yz-cross-sections of
3247the total model domain remains constant throughout the run depending on the chosen <a href="#conserve_volume_flow_mode">conserve_volume_flow_mode</a>.<br><br>Note that&nbsp;<span style="font-weight: bold;">conserve_volume_flow</span>
3248= <span style="font-style: italic;">.T.</span> requires <a href="#dp_external">dp_external</a> = <span style="font-style: italic;">.F.</span> .<br>
3249
3250
3251
3252
3253
3254
3255
3256      </td>
3257
3258
3259
3260
3261
3262
3263 </tr>
3264
3265
3266
3267
3268
3269
3270 <tr><td style="vertical-align: top;"><span style="font-weight: bold;"><a name="conserve_volume_flow_mode"></a>conserve_volume_flow_mode</span></td><td style="vertical-align: top;">C * 16</td><td style="vertical-align: top;"><span style="font-style: italic;">'default'</span></td><td>Modus of volume flow conservation.<br><br>The following values are allowed:<br><p style="font-style: normal;"><span style="font-style: italic;">'default'</span>
3271      </p>
3272
3273
3274
3275
3276
3277
3278 
3279     
3280     
3281     
3282     
3283     
3284     
3285      <ul><p>Per default, PALM uses&nbsp;<span style="font-style: italic;">'initial_profiles'</span> for cyclic lateral boundary conditions (<a href="#bc_lr">bc_lr</a> = <span style="font-style: italic;">'cyclic'</span> and <a href="#bc_ns">bc_ns</a> = <span style="font-style: italic;">'cyclic'</span>) and&nbsp;<span style="font-style: italic;">'inflow_profile'</span> for non-cyclic lateral boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> /= <span style="font-style: italic;">'cyclic'</span> or <a href="chapter_4.1.html#bc_ns">bc_ns</a> /= <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3286
3287
3288
3289
3290
3291
3292 
3293     
3294     
3295     
3296     
3297     
3298     
3299      <p style="font-style: italic;">'initial_profiles' </p>
3300
3301
3302
3303
3304
3305
3306
3307     
3308     
3309     
3310     
3311     
3312     
3313      <ul><p>The
3314target volume flow&nbsp;is calculated at t=0 from the initial profiles
3315of u and v.&nbsp;This setting is only allowed for&nbsp;cyclic lateral
3316boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> = <span style="font-style: italic;">'cyclic'</span> and <a href="chapter_4.1.html#bc_ns">bc_ns</a> = <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3317
3318
3319
3320
3321
3322
3323 
3324     
3325     
3326     
3327     
3328     
3329     
3330      <p style="font-style: normal;"><span style="font-style: italic;">'inflow_profile'</span>
3331      </p>
3332
3333
3334
3335
3336
3337
3338 
3339     
3340     
3341     
3342     
3343     
3344     
3345      <ul><p>The
3346target volume flow&nbsp;is&nbsp;calculated at every timestep from the
3347inflow profile of&nbsp;u or v, respectively. This setting&nbsp;is only
3348allowed for&nbsp;non-cyclic lateral boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> /= <span style="font-style: italic;">'cyclic'</span> or <a href="chapter_4.1.html#bc_ns">bc_ns</a> /= <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3349
3350
3351
3352
3353
3354
3355 
3356     
3357     
3358     
3359     
3360     
3361     
3362      <p style="font-style: italic;">'bulk_velocity' </p>
3363
3364
3365
3366
3367
3368
3369
3370     
3371     
3372     
3373     
3374     
3375     
3376      <ul><p>The target volume flow is calculated from a predefined bulk velocity (see <a href="#u_bulk">u_bulk</a> and <a href="#v_bulk">v_bulk</a>). This setting is only allowed for&nbsp;cyclic lateral boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> = <span style="font-style: italic;">'cyclic'</span> and <a href="chapter_4.1.html#bc_ns">bc_ns</a> = <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3377
3378
3379
3380
3381
3382
3383 
3384     
3385     
3386     
3387     
3388     
3389     
3390      <span style="font-style: italic;"></span>Note that&nbsp;<span style="font-weight: bold;">conserve_volume_flow_mode</span>
3391only comes into effect if <a href="#conserve_volume_flow">conserve_volume_flow</a> = <span style="font-style: italic;">.T. .</span> </td></tr>
3392
3393    <tr>
3394      <td style="vertical-align: top;"><a name="coupling_start_time"></a><span style="font-weight: bold;">coupling_start_time</span></td>
3395
3396      <td style="vertical-align: top;">R</td>
3397
3398      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3399
3400      <td style="vertical-align: top;">Simulation time of precursor run.
3401      <br>
3402      <br>
3403Sets the time period a precursor run shall run uncoupled. This
3404parameter is used to set up the precursor run control for
3405atmosphere-ocean-coupled runs. It has to be set individually to the
3406atmospheric / oceanic precursor run. The time in the data output will
3407show negative values during the precursor run. See documentation for
3408further information. </td>
3409
3410    </tr>
3411
3412      <tr><td style="vertical-align: top;"><a name="cthf"></a><span style="font-weight: bold;">cthf</span></td>
3413
3414      <td style="vertical-align: top;">R</td>
3415
3416      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3417
3418      <td style="vertical-align: top;">Average heat flux that is prescribed at the top of the plant canopy.<br>
3419
3420
3421      <br>
3422
3423
3424If <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>
3425
3426
3427It is assumed that solar radiation penetrates the canopy and warms the
3428foliage which, in turn, warms the air in contact with it. <br>
3429
3430
3431Note: Instead of using the value prescribed by <a href="#surface_heatflux">surface_heatflux</a>,
3432the near surface heat flux is determined from an exponential function
3433that is dependent on the cumulative leaf_area_index (Shaw and Schumann
3434(1992, Boundary Layer Meteorol., 61, 47-64)).</td>
3435
3436    </tr>
3437
3438    <tr>
3439
3440
3441
3442
3443
3444
3445 <td style="vertical-align: top;"> 
3446     
3447     
3448     
3449     
3450     
3451     
3452      <p><a name="cut_spline_overshoot"></a><b>cut_spline_overshoot</b></p>
3453
3454
3455
3456
3457
3458
3459
3460      </td>
3461
3462
3463
3464
3465
3466
3467 <td style="vertical-align: top;">L</td>
3468
3469
3470
3471
3472
3473
3474
3475      <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span></td>
3476
3477
3478
3479
3480
3481
3482 <td style="vertical-align: top;"> 
3483     
3484     
3485     
3486     
3487     
3488     
3489      <p>Cuts off of
3490so-called overshoots, which can occur with the
3491upstream-spline scheme.&nbsp; </p>
3492
3493
3494
3495
3496
3497
3498 
3499     
3500     
3501     
3502     
3503     
3504     
3505      <p><font color="#000000">The cubic splines tend to overshoot in
3506case of discontinuous changes of variables between neighbouring grid
3507points.</font><font color="#ff0000"> </font><font color="#000000">This
3508may lead to errors in calculating the advection tendency.</font>
3509Choice
3510of <b>cut_spline_overshoot</b> = <i>.TRUE.</i>
3511(switched on by
3512default)
3513allows variable values not to exceed an interval defined by the
3514respective adjacent grid points. This interval can be adjusted
3515seperately for every prognostic variable (see initialization parameters
3516      <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>,
3517etc.). This might be necessary in case that the
3518default interval has a non-tolerable effect on the model
3519results.&nbsp; </p>
3520
3521
3522
3523
3524
3525
3526 
3527     
3528     
3529     
3530     
3531     
3532     
3533      <p>Overshoots may also be removed
3534using the parameters <a href="#ups_limit_e">ups_limit_e</a>,
3535      <a href="#ups_limit_pt">ups_limit_pt</a>,
3536etc. as well as by applying a long-filter (see <a href="#long_filter_factor">long_filter_factor</a>).</p>
3537
3538
3539
3540
3541
3542
3543
3544      </td>
3545
3546
3547
3548
3549
3550
3551 </tr>
3552
3553
3554
3555
3556
3557
3558 <tr>
3559
3560
3561
3562
3563
3564
3565 <td style="vertical-align: top;"> 
3566     
3567     
3568     
3569     
3570     
3571     
3572      <p><a name="damp_level_1d"></a><b>damp_level_1d</b></p>
3573
3574
3575
3576
3577
3578
3579
3580      </td>
3581
3582
3583
3584
3585
3586
3587 <td style="vertical-align: top;">R</td>
3588
3589
3590
3591
3592
3593
3594
3595      <td style="vertical-align: top;"><span style="font-style: italic;">zu(nz+1)</span></td>
3596
3597
3598
3599
3600
3601
3602
3603      <td style="vertical-align: top;"> 
3604     
3605     
3606     
3607     
3608     
3609     
3610      <p>Height where
3611the damping layer begins in the 1d-model
3612(in m).&nbsp; </p>
3613
3614
3615
3616
3617
3618
3619 
3620     
3621     
3622     
3623     
3624     
3625     
3626      <p>This parameter is used to
3627switch on a damping layer for the
36281d-model, which is generally needed for the damping of inertia
3629oscillations. Damping is done by gradually increasing the value
3630of the eddy diffusivities about 10% per vertical grid level
3631(starting with the value at the height given by <b>damp_level_1d</b>,
3632or possibly from the next grid pint above), i.e. K<sub>m</sub>(k+1)
3633=
36341.1 * K<sub>m</sub>(k).
3635The values of K<sub>m</sub> are limited to 10 m**2/s at
3636maximum.&nbsp; <br>
3637
3638
3639
3640
3641
3642
3643
3644This parameter only comes into effect if the 1d-model is switched on
3645for
3646the initialization of the 3d-model using <a href="#initializing_actions">initializing_actions</a>
3647= <span style="font-style: italic;">'set_1d-model_profiles'</span>.
3648      <br>
3649
3650
3651
3652
3653
3654
3655 </p>
3656
3657
3658
3659
3660
3661
3662 </td>
3663
3664
3665
3666
3667
3668
3669 </tr>
3670
3671
3672
3673
3674
3675
3676 <tr>
3677
3678
3679
3680
3681
3682
3683 <td style="vertical-align: top;"><a name="dissipation_1d"></a><span style="font-weight: bold;">dissipation_1d</span><br>
3684
3685
3686
3687
3688
3689
3690
3691      </td>
3692
3693
3694
3695
3696
3697
3698 <td style="vertical-align: top;">C*20<br>
3699
3700
3701
3702
3703
3704
3705
3706      </td>
3707
3708
3709
3710
3711
3712
3713 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
3714
3715
3716
3717
3718
3719
3720 <span style="font-style: italic;">model'</span><br>
3721
3722
3723
3724
3725
3726
3727 </td>
3728
3729
3730
3731
3732
3733
3734
3735      <td style="vertical-align: top;">Calculation method for
3736the energy dissipation term in the TKE equation of the 1d-model.<br>
3737
3738
3739
3740
3741
3742
3743
3744      <br>
3745
3746
3747
3748
3749
3750
3751
3752By default the dissipation is calculated as in the 3d-model using diss
3753= (0.19 + 0.74 * l / l_grid) * e**1.5 / l.<br>
3754
3755
3756
3757
3758
3759
3760 <br>
3761
3762
3763
3764
3765
3766
3767
3768Setting <span style="font-weight: bold;">dissipation_1d</span>
3769= <span style="font-style: italic;">'detering'</span>
3770forces the dissipation to be calculated as diss = 0.064 * e**1.5 / l.<br>
3771
3772
3773
3774
3775
3776
3777
3778      </td>
3779
3780
3781
3782
3783
3784
3785 </tr>
3786    <tr><td style="vertical-align: top;"><p><a name="dp_external"></a><b>dp_external</b></p></td><td style="vertical-align: top;">L</td><td style="vertical-align: top; font-style: italic;">.F.</td><td>External pressure gradient switch.<br><br>This
3787parameter is used to switch on/off an external pressure gradient as
3788driving force. The external pressure gradient is controlled by the
3789parameters <a href="#dp_smooth">dp_smooth</a>, <a href="#dp_level_b">dp_level_b</a> and <a href="#dpdxy">dpdxy</a>.<br><br>Note that&nbsp;<span style="font-weight: bold;">dp_external</span> = <span style="font-style: italic;">.T.</span> requires <a href="#conserve_volume_flow">conserve_volume_flow</a> =<span style="font-style: italic;"> .F. </span>It is normally recommended to disable the Coriolis force by setting <a href="#omega">omega</a> = 0.0.</td></tr><tr><td style="vertical-align: top;"><p><a name="dp_smooth"></a><b>dp_smooth</b></p></td><td style="vertical-align: top;">L</td><td style="vertical-align: top; font-style: italic;">.F.</td><td>Vertically smooth the external pressure gradient using a sinusoidal smoothing function.<br><br>This parameter only applies if <a href="#dp_external">dp_external</a> = <span style="font-style: italic;">.T. </span>. It is useful in combination with&nbsp;<a href="#dp_level_b">dp_level_b</a> &gt;&gt; 0 to generate a non-accelerated boundary layer well below&nbsp;<a href="#dp_level_b">dp_level_b</a>.</td></tr><tr><td style="vertical-align: top;"><p><a name="dp_level_b"></a><b>dp_level_b</b></p></td><td style="vertical-align: top;">R</td><td style="vertical-align: top; font-style: italic;">0.0</td><td><font size="3">Lower
3790limit of the vertical range for which the external pressure gradient is applied (</font>in <font size="3">m).</font><br><br>This parameter only applies if <a href="#dp_external">dp_external</a> = <span style="font-style: italic;">.T. </span><span lang="en-GB">It
3791must hold the condition zu(0) &lt;= <b>dp_level_b</b>
3792&lt;= zu(</span><a href="#nz"><span lang="en-GB">nz</span></a><span lang="en-GB">)</span><span lang="en-GB">.&nbsp;</span>It can be used in combination with&nbsp;<a href="#dp_smooth">dp_smooth</a> = <span style="font-style: italic;">.T.</span> to generate a non-accelerated boundary layer well below&nbsp;<span style="font-weight: bold;">dp_level_b</span> if&nbsp;<span style="font-weight: bold;">dp_level_b</span> &gt;&gt; 0.<br><br>Note
3793that there is no upper limit of the vertical range because the external
3794pressure gradient is always applied up to the top of the model domain.</td></tr><tr><td style="vertical-align: top;"><p><a name="dpdxy"></a><b>dpdxy</b></p></td><td style="vertical-align: top;">R(2)</td><td style="font-style: italic; vertical-align: top;">2 * 0.0</td><td>Values of the external pressure gradient applied in x- and y-direction, respectively (in Pa/m).<br><br>This parameter only applies if <a href="#dp_external">dp_external</a> = <span style="font-style: italic;">.T. </span>It sets the pressure gradient values. Negative values mean an acceleration, positive values mean deceleration. For example, <span style="font-weight: bold;">dpdxy</span> = -0.0002, 0.0, drives the flow in positive x-direction, <span lang="en-GB"></span></td></tr>
3795
3796
3797
3798
3799
3800
3801    <tr>
3802
3803      <td style="vertical-align: top;"><a name="drag_coefficient"></a><span style="font-weight: bold;">drag_coefficient</span></td>
3804
3805      <td style="vertical-align: top;">R</td>
3806
3807      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3808
3809      <td style="vertical-align: top;">Drag coefficient used in the plant canopy model.<br>
3810
3811      <br>
3812
3813This 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>
3814
3815    </tr>
3816
3817    <tr>
3818
3819
3820
3821
3822
3823
3824 <td style="vertical-align: top;"> 
3825     
3826     
3827     
3828     
3829     
3830     
3831      <p><a name="dt"></a><b>dt</b></p>
3832
3833
3834
3835
3836
3837
3838 </td>
3839
3840
3841
3842
3843
3844
3845
3846      <td style="vertical-align: top;">R</td>
3847
3848
3849
3850
3851
3852
3853 <td style="vertical-align: top;"><span style="font-style: italic;">variable</span></td>
3854
3855
3856
3857
3858
3859
3860
3861      <td style="vertical-align: top;"> 
3862     
3863     
3864     
3865     
3866     
3867     
3868      <p>Time step for
3869the 3d-model (in s).&nbsp; </p>
3870
3871
3872
3873
3874
3875
3876 
3877     
3878     
3879     
3880     
3881     
3882     
3883      <p>By default, (i.e.
3884if a Runge-Kutta scheme is used, see <a href="#timestep_scheme">timestep_scheme</a>)
3885the value of the time step is calculating after each time step
3886(following the time step criteria) and
3887used for the next step.</p>
3888
3889
3890
3891
3892
3893
3894 
3895     
3896     
3897     
3898     
3899     
3900     
3901      <p>If the user assigns <b>dt</b>
3902a value, then the time step is
3903fixed to this value throughout the whole run (whether it fulfills the
3904time step
3905criteria or not). However, changes are allowed for restart runs,
3906because <b>dt</b> can also be used as a <a href="chapter_4.2.html#dt_laufparameter">run
3907parameter</a>.&nbsp; </p>
3908
3909
3910
3911
3912
3913
3914 
3915     
3916     
3917     
3918     
3919     
3920     
3921      <p>In case that the
3922calculated time step meets the condition<br>
3923
3924
3925
3926
3927
3928
3929 </p>
3930
3931
3932
3933
3934
3935
3936 
3937     
3938     
3939     
3940     
3941     
3942     
3943      <ul>
3944
3945
3946
3947
3948
3949
3950
3951       
3952       
3953       
3954       
3955       
3956       
3957        <p><b>dt</b> &lt; 0.00001 * <a href="chapter_4.2.html#dt_max">dt_max</a> (with dt_max
3958= 20.0)</p>
3959
3960
3961
3962
3963
3964
3965 
3966     
3967     
3968     
3969     
3970     
3971     
3972      </ul>
3973
3974
3975
3976
3977
3978
3979 
3980     
3981     
3982     
3983     
3984     
3985     
3986      <p>the simulation will be
3987aborted. Such situations usually arise
3988in case of any numerical problem / instability which causes a
3989non-realistic increase of the wind speed.&nbsp; </p>
3990
3991
3992
3993
3994
3995
3996 
3997     
3998     
3999     
4000     
4001     
4002     
4003      <p>A
4004small time step due to a large mean horizontal windspeed
4005speed may be enlarged by using a coordinate transformation (see <a href="#galilei_transformation">galilei_transformation</a>),
4006in order to spare CPU time.<br>
4007
4008
4009
4010
4011
4012
4013 </p>
4014
4015
4016
4017
4018
4019
4020 
4021     
4022     
4023     
4024     
4025     
4026     
4027      <p>If the
4028leapfrog timestep scheme is used (see <a href="#timestep_scheme">timestep_scheme</a>)
4029a temporary time step value dt_new is calculated first, with dt_new = <a href="chapter_4.2.html#fcl_factor">cfl_factor</a>
4030* dt_crit where dt_crit is the maximum timestep allowed by the CFL and
4031diffusion condition. Next it is examined whether dt_new exceeds or
4032falls below the
4033value of the previous timestep by at
4034least +5 % / -2%. If it is smaller, <span style="font-weight: bold;">dt</span>
4035= dt_new is immediately used for the next timestep. If it is larger,
4036then <span style="font-weight: bold;">dt </span>=
40371.02 * dt_prev
4038(previous timestep) is used as the new timestep, however the time
4039step is only increased if the last change of the time step is dated
4040back at
4041least 30 iterations. If dt_new is located in the interval mentioned
4042above, then dt
4043does not change at all. By doing so, permanent time step changes as
4044well as large
4045sudden changes (increases) in the time step are avoided.</p>
4046
4047
4048
4049
4050
4051
4052 </td>
4053
4054
4055
4056
4057
4058
4059
4060    </tr>
4061
4062
4063
4064
4065
4066
4067 <tr>
4068
4069
4070
4071
4072
4073
4074 <td style="vertical-align: top;">
4075     
4076     
4077     
4078     
4079     
4080     
4081      <p><a name="dt_pr_1d"></a><b>dt_pr_1d</b></p>
4082
4083
4084
4085
4086
4087
4088
4089      </td>
4090
4091
4092
4093
4094
4095
4096 <td style="vertical-align: top;">R</td>
4097
4098
4099
4100
4101
4102
4103
4104      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4105
4106
4107
4108
4109
4110
4111
4112      <td style="vertical-align: top;"> 
4113     
4114     
4115     
4116     
4117     
4118     
4119      <p>Temporal
4120interval of vertical profile output of the 1D-model
4121(in s).&nbsp; </p>
4122
4123
4124
4125
4126
4127
4128 
4129     
4130     
4131     
4132     
4133     
4134     
4135      <p>Data are written in ASCII
4136format to file <a href="chapter_3.4.html#LIST_PROFIL_1D">LIST_PROFIL_1D</a>.
4137This parameter is only in effect if the 1d-model has been switched on
4138for the
4139initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4140= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4141
4142
4143
4144
4145
4146
4147
4148      </td>
4149
4150
4151
4152
4153
4154
4155 </tr>
4156
4157
4158
4159
4160
4161
4162 <tr>
4163
4164
4165
4166
4167
4168
4169 <td style="vertical-align: top;"> 
4170     
4171     
4172     
4173     
4174     
4175     
4176      <p><a name="dt_run_control_1d"></a><b>dt_run_control_1d</b></p>
4177
4178
4179
4180
4181
4182
4183
4184      </td>
4185
4186
4187
4188
4189
4190
4191 <td style="vertical-align: top;">R</td>
4192
4193
4194
4195
4196
4197
4198
4199      <td style="vertical-align: top;"><span style="font-style: italic;">60.0</span></td>
4200
4201
4202
4203
4204
4205
4206 <td style="vertical-align: top;"> 
4207     
4208     
4209     
4210     
4211     
4212     
4213      <p>Temporal interval of
4214runtime control output of the 1d-model
4215(in s).&nbsp; </p>
4216
4217
4218
4219
4220
4221
4222 
4223     
4224     
4225     
4226     
4227     
4228     
4229      <p>Data are written in ASCII
4230format to file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
4231This parameter is only in effect if the 1d-model is switched on for the
4232initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4233= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4234
4235
4236
4237
4238
4239
4240
4241      </td>
4242
4243
4244
4245
4246
4247
4248 </tr>
4249
4250
4251
4252
4253
4254
4255 <tr>
4256
4257
4258
4259
4260
4261
4262 <td style="vertical-align: top;"> 
4263     
4264     
4265     
4266     
4267     
4268     
4269      <p><a name="dx"></a><b>dx</b></p>
4270
4271
4272
4273
4274
4275
4276
4277      </td>
4278
4279
4280
4281
4282
4283
4284 <td style="vertical-align: top;">R</td>
4285
4286
4287
4288
4289
4290
4291
4292      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4293
4294
4295
4296
4297
4298
4299 <td style="vertical-align: top;"> 
4300     
4301     
4302     
4303     
4304     
4305     
4306      <p>Horizontal grid
4307spacing along the x-direction (in m).&nbsp; </p>
4308
4309
4310
4311
4312
4313
4314 
4315     
4316     
4317     
4318     
4319     
4320     
4321      <p>Along
4322x-direction only a constant grid spacing is allowed.</p>
4323
4324
4325
4326
4327
4328
4329     
4330     
4331     
4332     
4333     
4334     
4335      <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>
4336and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4337
4338
4339
4340
4341
4342
4343 </td>
4344
4345
4346
4347
4348
4349
4350
4351    </tr>
4352
4353
4354
4355
4356
4357
4358 <tr>
4359
4360
4361
4362
4363
4364
4365 <td style="vertical-align: top;">
4366     
4367     
4368     
4369     
4370     
4371     
4372      <p><a name="dy"></a><b>dy</b></p>
4373
4374
4375
4376
4377
4378
4379
4380      </td>
4381
4382
4383
4384
4385
4386
4387 <td style="vertical-align: top;">R</td>
4388
4389
4390
4391
4392
4393
4394
4395      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4396
4397
4398
4399
4400
4401
4402 <td style="vertical-align: top;"> 
4403     
4404     
4405     
4406     
4407     
4408     
4409      <p>Horizontal grid
4410spacing along the y-direction (in m).&nbsp; </p>
4411
4412
4413
4414
4415
4416
4417 
4418     
4419     
4420     
4421     
4422     
4423     
4424      <p>Along y-direction only a constant grid spacing is allowed.</p>
4425
4426
4427
4428
4429
4430
4431     
4432     
4433     
4434     
4435     
4436     
4437      <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>
4438and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4439
4440
4441
4442
4443
4444
4445 </td>
4446
4447
4448
4449
4450
4451
4452
4453    </tr>
4454
4455
4456
4457
4458
4459
4460 <tr>
4461
4462
4463
4464
4465
4466
4467 <td style="vertical-align: top;">
4468     
4469     
4470     
4471     
4472     
4473     
4474      <p><a name="dz"></a><b>dz</b></p>
4475
4476
4477
4478
4479
4480
4481
4482      </td>
4483
4484
4485
4486
4487
4488
4489 <td style="vertical-align: top;">R</td>
4490
4491
4492
4493
4494
4495
4496
4497      <td style="vertical-align: top;"><br>
4498
4499
4500
4501
4502
4503
4504 </td>
4505
4506
4507
4508
4509
4510
4511 <td style="vertical-align: top;"> 
4512     
4513     
4514     
4515     
4516     
4517     
4518      <p>Vertical grid
4519spacing (in m).&nbsp; </p>
4520
4521
4522
4523
4524
4525
4526 
4527     
4528     
4529     
4530     
4531     
4532     
4533      <p>This parameter must be
4534assigned by the user, because no
4535default value is given.<br>
4536
4537
4538
4539
4540
4541
4542 </p>
4543
4544
4545
4546
4547
4548
4549 
4550     
4551     
4552     
4553     
4554     
4555     
4556      <p>By default, the
4557model uses constant grid spacing along z-direction, but it can be
4558stretched using the parameters <a href="#dz_stretch_level">dz_stretch_level</a>
4559and <a href="#dz_stretch_factor">dz_stretch_factor</a>.
4560In case of stretching, a maximum allowed grid spacing can be given by <a href="#dz_max">dz_max</a>.<br>
4561
4562
4563
4564
4565
4566
4567 </p>
4568
4569
4570
4571
4572
4573
4574 
4575     
4576     
4577     
4578     
4579     
4580     
4581      <p>Assuming
4582a constant <span style="font-weight: bold;">dz</span>,
4583the scalar levels (zu) are calculated directly by:&nbsp; </p>
4584
4585
4586
4587
4588
4589
4590
4591     
4592     
4593     
4594     
4595     
4596     
4597      <ul>
4598
4599
4600
4601
4602
4603
4604 
4605       
4606       
4607       
4608       
4609       
4610       
4611        <p>zu(0) = - dz * 0.5&nbsp; <br>
4612
4613
4614
4615
4616
4617
4618
4619zu(1) = dz * 0.5</p>
4620
4621
4622
4623
4624
4625
4626 
4627     
4628     
4629     
4630     
4631     
4632     
4633      </ul>
4634
4635
4636
4637
4638
4639
4640 
4641     
4642     
4643     
4644     
4645     
4646     
4647      <p>The w-levels lie
4648half between them:&nbsp; </p>
4649
4650
4651
4652
4653
4654
4655 
4656     
4657     
4658     
4659     
4660     
4661     
4662      <ul>
4663
4664
4665
4666
4667
4668
4669 
4670       
4671       
4672       
4673       
4674       
4675       
4676        <p>zw(k) =
4677( zu(k) + zu(k+1) ) * 0.5</p>
4678
4679
4680
4681
4682
4683
4684 
4685     
4686     
4687     
4688     
4689     
4690     
4691      </ul>
4692
4693
4694
4695
4696
4697
4698 </td>
4699
4700
4701
4702
4703
4704
4705 </tr>
4706
4707
4708
4709
4710
4711
4712
4713    <tr>
4714
4715
4716
4717
4718
4719
4720      <td style="vertical-align: top;"><a name="dz_max"></a><span style="font-weight: bold;">dz_max</span></td>
4721
4722
4723
4724
4725
4726
4727      <td style="vertical-align: top;">R</td>
4728
4729
4730
4731
4732
4733
4734      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4735
4736
4737
4738
4739
4740
4741      <td style="vertical-align: top;">Allowed maximum vertical grid
4742spacing (in m).<br>
4743
4744
4745
4746
4747
4748
4749      <br>
4750
4751
4752
4753
4754
4755
4756If the vertical grid is stretched
4757(see <a href="#dz_stretch_factor">dz_stretch_factor</a>
4758and <a href="#dz_stretch_level">dz_stretch_level</a>),
4759      <span style="font-weight: bold;">dz_max</span> can
4760be used to limit the vertical grid spacing.</td>
4761
4762
4763
4764
4765
4766
4767    </tr>
4768
4769
4770
4771
4772
4773
4774    <tr>
4775
4776
4777
4778
4779
4780
4781
4782      <td style="vertical-align: top;"> 
4783     
4784     
4785     
4786     
4787     
4788     
4789      <p><a name="dz_stretch_factor"></a><b>dz_stretch_factor</b></p>
4790
4791
4792
4793
4794
4795
4796
4797      </td>
4798
4799
4800
4801
4802
4803
4804 <td style="vertical-align: top;">R</td>
4805
4806
4807
4808
4809
4810
4811
4812      <td style="vertical-align: top;"><span style="font-style: italic;">1.08</span></td>
4813
4814
4815
4816
4817
4818
4819 <td style="vertical-align: top;"> 
4820     
4821     
4822     
4823     
4824     
4825     
4826      <p>Stretch factor for a
4827vertically stretched grid (see <a href="#dz_stretch_level">dz_stretch_level</a>).&nbsp;
4828      </p>
4829
4830
4831
4832
4833
4834
4835 
4836     
4837     
4838     
4839     
4840     
4841     
4842      <p>The stretch factor should not exceed a value of
4843approx. 1.10 -
48441.12, otherwise the discretization errors due to the stretched grid not
4845negligible any more. (refer Kalnay de Rivas)</p>
4846
4847
4848
4849
4850
4851
4852 </td>
4853
4854
4855
4856
4857
4858
4859 </tr>
4860
4861
4862
4863
4864
4865
4866
4867    <tr>
4868
4869
4870
4871
4872
4873
4874 <td style="vertical-align: top;"> 
4875     
4876     
4877     
4878     
4879     
4880     
4881      <p><a name="dz_stretch_level"></a><b>dz_stretch_level</b></p>
4882
4883
4884
4885
4886
4887
4888
4889      </td>
4890
4891
4892
4893
4894
4895
4896 <td style="vertical-align: top;">R</td>
4897
4898
4899
4900
4901
4902
4903
4904      <td style="vertical-align: top;"><span style="font-style: italic;">100000.0</span><br>
4905
4906
4907
4908
4909
4910
4911 </td>
4912
4913
4914
4915
4916
4917
4918
4919      <td style="vertical-align: top;"> 
4920     
4921     
4922     
4923     
4924     
4925     
4926      <p>Height level
4927above/below which the grid is to be stretched
4928vertically (in m).&nbsp; </p>
4929
4930
4931
4932
4933
4934
4935 
4936     
4937     
4938     
4939     
4940     
4941     
4942      <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
4943vertically. The vertical grid
4944spacings <a href="#dz">dz</a>
4945above this level are calculated as&nbsp; </p>
4946
4947
4948
4949
4950
4951
4952 
4953     
4954     
4955     
4956     
4957     
4958     
4959      <ul>
4960
4961
4962
4963
4964
4965
4966 
4967       
4968       
4969       
4970       
4971       
4972       
4973        <p><b>dz</b>(k+1)
4974= <b>dz</b>(k) * <a href="#dz_stretch_factor">dz_stretch_factor</a></p>
4975
4976
4977
4978
4979
4980
4981
4982     
4983     
4984     
4985     
4986     
4987     
4988      </ul>
4989
4990
4991
4992
4993
4994
4995 
4996     
4997     
4998     
4999     
5000     
5001     
5002      <p>and used as spacings for the scalar levels (zu).
5003The
5004w-levels are then defined as:&nbsp; </p>
5005
5006
5007
5008
5009
5010
5011 
5012     
5013     
5014     
5015     
5016     
5017     
5018      <ul>
5019
5020
5021
5022
5023
5024
5025 
5026       
5027       
5028       
5029       
5030       
5031       
5032        <p>zw(k)
5033= ( zu(k) + zu(k+1) ) * 0.5.
5034
5035 
5036     
5037      </p>
5038
5039
5040
5041
5042     
5043     
5044     
5045     
5046      </ul>
5047
5048
5049
5050
5051     
5052     
5053     
5054     
5055      <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
5056vertically. The vertical grid
5057spacings <a href="chapter_4.1.html#dz">dz</a> below this level are calculated correspondingly as
5058
5059 
5060     
5061      </p>
5062
5063
5064
5065
5066     
5067     
5068     
5069     
5070      <ul>
5071
5072
5073
5074
5075       
5076       
5077       
5078       
5079        <p><b>dz</b>(k-1)
5080= <b>dz</b>(k) * <a href="chapter_4.1.html#dz_stretch_factor">dz_stretch_factor</a>.</p>
5081
5082
5083
5084
5085     
5086     
5087     
5088     
5089      </ul>
5090
5091
5092
5093
5094
5095
5096 </td>
5097
5098
5099
5100
5101
5102
5103 </tr>
5104
5105
5106
5107
5108
5109
5110
5111    <tr>
5112
5113
5114
5115
5116
5117      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_init"></a>e_init</span></td>
5118
5119
5120
5121
5122
5123      <td style="vertical-align: top;">R</td>
5124
5125
5126
5127
5128
5129      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5130
5131
5132
5133
5134
5135      <td>Initial subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5136
5137
5138
5139
5140
5141
5142
5143      <br>
5144
5145
5146
5147
5148
5149
5150This
5151option 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>
5152
5153
5154
5155
5156
5157    </tr>
5158
5159
5160
5161
5162
5163    <tr>
5164
5165
5166
5167
5168
5169
5170 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_min"></a>e_min</span></td>
5171
5172
5173
5174
5175
5176
5177
5178      <td style="vertical-align: top;">R</td>
5179
5180
5181
5182
5183
5184
5185 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5186
5187
5188
5189
5190
5191
5192 <td>Minimum
5193subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5194
5195
5196
5197
5198
5199
5200
5201      <br>
5202
5203
5204
5205
5206
5207
5208This
5209option&nbsp;adds artificial viscosity to the flow by ensuring that
5210the
5211subgrid-scale TKE does not fall below the minimum threshold <span style="font-weight: bold;">e_min</span>.</td>
5212
5213
5214
5215
5216
5217
5218 </tr>
5219
5220
5221
5222
5223
5224
5225
5226    <tr>
5227
5228
5229
5230
5231
5232
5233 <td style="vertical-align: top;"> 
5234     
5235     
5236     
5237     
5238     
5239     
5240      <p><a name="end_time_1d"></a><b>end_time_1d</b></p>
5241
5242
5243
5244
5245
5246
5247
5248      </td>
5249
5250
5251
5252
5253
5254
5255 <td style="vertical-align: top;">R</td>
5256
5257
5258
5259
5260
5261
5262
5263      <td style="vertical-align: top;"><span style="font-style: italic;">864000.0</span><br>
5264
5265
5266
5267
5268
5269
5270 </td>
5271
5272
5273
5274
5275
5276
5277
5278      <td style="vertical-align: top;"> 
5279     
5280     
5281     
5282     
5283     
5284     
5285      <p>Time to be
5286simulated for the 1d-model (in s).&nbsp; </p>
5287
5288
5289
5290
5291
5292
5293 
5294     
5295     
5296     
5297     
5298     
5299     
5300      <p>The
5301default value corresponds to a simulated time of 10 days.
5302Usually, after such a period the inertia oscillations have completely
5303decayed and the solution of the 1d-model can be regarded as stationary
5304(see <a href="#damp_level_1d">damp_level_1d</a>).
5305This parameter is only in effect if the 1d-model is switched on for the
5306initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
5307= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
5308
5309
5310
5311
5312
5313
5314
5315      </td>
5316
5317
5318
5319
5320
5321
5322 </tr>
5323
5324
5325
5326
5327
5328
5329 <tr>
5330
5331
5332
5333
5334
5335
5336 <td style="vertical-align: top;"> 
5337     
5338     
5339     
5340     
5341     
5342     
5343      <p><a name="fft_method"></a><b>fft_method</b></p>
5344
5345
5346
5347
5348
5349
5350
5351      </td>
5352
5353
5354
5355
5356
5357
5358 <td style="vertical-align: top;">C * 20</td>
5359
5360
5361
5362
5363
5364
5365
5366      <td style="vertical-align: top;"><span style="font-style: italic;">'system-</span><br style="font-style: italic;">
5367
5368
5369
5370
5371
5372
5373 <span style="font-style: italic;">specific'</span></td>
5374
5375
5376
5377
5378
5379
5380
5381      <td style="vertical-align: top;"> 
5382     
5383     
5384     
5385     
5386     
5387     
5388      <p>FFT-method to
5389be used.<br>
5390
5391
5392
5393
5394
5395
5396 </p>
5397
5398
5399
5400
5401
5402
5403 
5404     
5405     
5406     
5407     
5408     
5409     
5410      <p><br>
5411
5412
5413
5414
5415
5416
5417
5418The fast fourier transformation (FFT) is used for solving the
5419perturbation pressure equation with a direct method (see <a href="chapter_4.2.html#psolver">psolver</a>)
5420and for calculating power spectra (see optional software packages,
5421section <a href="chapter_4.2.html#spectra_package">4.2</a>).</p>
5422
5423
5424
5425
5426
5427
5428
5429     
5430     
5431     
5432     
5433     
5434     
5435      <p><br>
5436
5437
5438
5439
5440
5441
5442
5443By default, system-specific, optimized routines from external
5444vendor libraries are used. However, these are available only on certain
5445computers and there are more or less severe restrictions concerning the
5446number of gridpoints to be used with them.<br>
5447
5448
5449
5450
5451
5452
5453 </p>
5454
5455
5456
5457
5458
5459
5460 
5461     
5462     
5463     
5464     
5465     
5466     
5467      <p>There
5468are two other PALM internal methods available on every
5469machine (their respective source code is part of the PALM source code):</p>
5470
5471
5472
5473
5474
5475
5476
5477     
5478     
5479     
5480     
5481     
5482     
5483      <p>1.: The <span style="font-weight: bold;">Temperton</span>-method
5484from Clive Temperton (ECWMF) which is computationally very fast and
5485switched on with <b>fft_method</b> = <span style="font-style: italic;">'temperton-algorithm'</span>.
5486The number of horizontal gridpoints (nx+1, ny+1) to be used with this
5487method must be composed of prime factors 2, 3 and 5.<br>
5488
5489
5490
5491
5492
5493
5494 </p>
5495
5496
5497
5498
5499
5500
5501
55022.: The <span style="font-weight: bold;">Singleton</span>-method
5503which is very slow but has no restrictions concerning the number of
5504gridpoints to be used with, switched on with <b>fft_method</b>
5505= <span style="font-style: italic;">'singleton-algorithm'</span>.
5506      </td>
5507
5508
5509
5510
5511
5512
5513 </tr>
5514
5515
5516
5517
5518
5519
5520 <tr>
5521
5522
5523
5524
5525
5526
5527 <td style="vertical-align: top;"> 
5528     
5529     
5530     
5531     
5532     
5533     
5534      <p><a name="galilei_transformation"></a><b>galilei_transformation</b></p>
5535
5536
5537
5538
5539
5540
5541
5542      </td>
5543
5544
5545
5546
5547
5548
5549 <td style="vertical-align: top;">L</td>
5550
5551
5552
5553
5554
5555
5556
5557      <td style="vertical-align: top;"><i>.F.</i></td>
5558
5559
5560
5561
5562
5563
5564
5565      <td style="vertical-align: top;">Application of a
5566Galilei-transformation to the
5567coordinate
5568system of the model.<br>
5569
5570
5571
5572
5573
5574
5575     
5576     
5577     
5578     
5579     
5580     
5581      <p>With <b>galilei_transformation</b>
5582= <i>.T.,</i> a so-called
5583Galilei-transformation is switched on which ensures that the coordinate
5584system of the model is moved along with the geostrophical wind.
5585Alternatively, the model domain can be moved along with the averaged
5586horizontal wind (see <a href="#use_ug_for_galilei_tr">use_ug_for_galilei_tr</a>,
5587this can and will naturally change in time). With this method,
5588numerical inaccuracies of the Piascek - Williams - scheme (concerns in
5589particular the momentum advection) are minimized. Beyond that, in the
5590majority of cases the lower relative velocities in the moved system
5591permit a larger time step (<a href="#dt">dt</a>).
5592Switching the transformation on is only worthwhile if the geostrophical
5593wind (ug, vg)
5594and the averaged horizontal wind clearly deviate from the value 0. In
5595each case, the distance the coordinate system has been moved is written
5596to the file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.&nbsp;
5597      </p>
5598
5599
5600
5601
5602
5603
5604 
5605     
5606     
5607     
5608     
5609     
5610     
5611      <p>Non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
5612and <a href="#bc_ns">bc_ns</a>), the specification
5613of a gestrophic
5614wind that is not constant with height
5615as well as e.g. stationary inhomogeneities at the bottom boundary do
5616not allow the use of this transformation.</p>
5617
5618
5619
5620
5621
5622
5623 </td>
5624
5625
5626
5627
5628
5629
5630 </tr>
5631
5632
5633
5634
5635
5636
5637
5638    <tr>
5639
5640
5641
5642
5643
5644
5645 <td style="vertical-align: top;"> 
5646     
5647     
5648     
5649     
5650     
5651     
5652      <p><a name="grid_matching"></a><b>grid_matching</b></p>
5653
5654
5655
5656
5657
5658
5659
5660      </td>
5661
5662
5663
5664
5665
5666
5667 <td style="vertical-align: top;">C * 6</td>
5668
5669
5670
5671
5672
5673
5674
5675      <td style="vertical-align: top;"><span style="font-style: italic;">'strict'</span></td>
5676
5677
5678
5679
5680
5681
5682 <td style="vertical-align: top;">Variable to adjust the
5683subdomain
5684sizes in parallel runs.<br>
5685
5686
5687
5688
5689
5690
5691 <br>
5692
5693
5694
5695
5696
5697
5698
5699For <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>,
5700the subdomains are forced to have an identical
5701size on all processors. In this case the processor numbers in the
5702respective directions of the virtual processor net must fulfill certain
5703divisor conditions concerning the grid point numbers in the three
5704directions (see <a href="#nx">nx</a>, <a href="#ny">ny</a>
5705and <a href="#nz">nz</a>).
5706Advantage of this method is that all PEs bear the same computational
5707load.<br>
5708
5709
5710
5711
5712
5713
5714 <br>
5715
5716
5717
5718
5719
5720
5721
5722There is no such restriction by default, because then smaller
5723subdomains are allowed on those processors which
5724form the right and/or north boundary of the virtual processor grid. On
5725all other processors the subdomains are of same size. Whether smaller
5726subdomains are actually used, depends on the number of processors and
5727the grid point numbers used. Information about the respective settings
5728are 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>
5729
5730
5731
5732
5733
5734
5735
5736      <br>
5737
5738
5739
5740
5741
5742
5743
5744When 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>)
5745only <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>
5746is allowed.<br>
5747
5748
5749
5750
5751
5752
5753 <br>
5754
5755
5756
5757
5758
5759
5760 <b>Note:</b><br>
5761
5762
5763
5764
5765
5766
5767
5768In some cases for small processor numbers there may be a very bad load
5769balancing among the
5770processors which may reduce the performance of the code.</td>
5771
5772
5773
5774
5775
5776
5777 </tr>
5778
5779
5780
5781
5782
5783
5784
5785    <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
5786switch on the prognostic equation for specific
5787humidity q.<br>
5788
5789
5790
5791
5792
5793
5794 </p>
5795
5796
5797
5798
5799
5800
5801 
5802     
5803     
5804     
5805     
5806     
5807     
5808      <p>The initial vertical
5809profile 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>
5810and <a href="chapter_4.1.html#q_vertical_gradient_level">q_vertical_gradient_level</a>.&nbsp;
5811Boundary conditions can be set via <a href="chapter_4.1.html#q_surface_initial_change">q_surface_initial_change</a>
5812and <a href="chapter_4.1.html#surface_waterflux">surface_waterflux</a>.<br>
5813
5814
5815
5816
5817
5818
5819
5820      </p>
5821
5822
5823
5824
5825
5826
5827
5828If the condensation scheme is switched on (<a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
5829= .TRUE.), q becomes the total liquid water content (sum of specific
5830humidity 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>),
5831this parameter defines the vertical thickness of the turbulent layer up
5832to which the turbulence extracted at the recycling plane (see <a href="chapter_4.1.html#recycling_width">recycling_width</a>)
5833shall be imposed to the inflow. Above this level the turbulence signal
5834is linearly damped to zero. The transition range within which the
5835signal 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>
5836
5837
5838
5839
5840
5841
5842 <td style="vertical-align: top;"><a name="inflow_disturbance_begin"></a><b>inflow_disturbance_<br>
5843
5844
5845
5846
5847
5848
5849
5850begin</b></td>
5851
5852
5853
5854
5855
5856
5857 <td style="vertical-align: top;">I</td>
5858
5859
5860
5861
5862
5863
5864
5865      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(10,</span><br style="font-style: italic;">
5866
5867
5868
5869
5870
5871
5872 <span style="font-style: italic;">nx/2 or ny/2)</span></td>
5873
5874
5875
5876
5877
5878
5879
5880      <td style="vertical-align: top;">Lower
5881limit of the horizontal range for which random perturbations are to be
5882imposed on the horizontal velocity field (gridpoints).<br>
5883
5884
5885
5886
5887
5888
5889 <br>
5890
5891
5892
5893
5894
5895
5896
5897If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5898or <a href="#bc_ns">bc_ns</a>),
5899this parameter gives the gridpoint number (counted horizontally from
5900the inflow)&nbsp; from which on perturbations are imposed on the
5901horizontal velocity field. Perturbations must be switched on with
5902parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5903
5904
5905
5906
5907
5908
5909
5910    </tr>
5911
5912
5913
5914
5915
5916
5917 <tr>
5918
5919
5920
5921
5922
5923
5924 <td style="vertical-align: top;"><a name="inflow_disturbance_end"></a><b>inflow_disturbance_<br>
5925
5926
5927
5928
5929
5930
5931
5932end</b></td>
5933
5934
5935
5936
5937
5938
5939 <td style="vertical-align: top;">I</td>
5940
5941
5942
5943
5944
5945
5946
5947      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(100,</span><br style="font-style: italic;">
5948
5949
5950
5951
5952
5953
5954 <span style="font-style: italic;">3/4*nx or</span><br style="font-style: italic;">
5955
5956
5957
5958
5959
5960
5961 <span style="font-style: italic;">3/4*ny)</span></td>
5962
5963
5964
5965
5966
5967
5968 <td style="vertical-align: top;">Upper
5969limit of the horizontal range for which random perturbations are
5970to be imposed on the horizontal velocity field (gridpoints).<br>
5971
5972
5973
5974
5975
5976
5977 <br>
5978
5979
5980
5981
5982
5983
5984
5985If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5986or <a href="#bc_ns">bc_ns</a>),
5987this parameter gives the gridpoint number (counted horizontally from
5988the inflow)&nbsp; unto which perturbations are imposed on the
5989horizontal
5990velocity field. Perturbations must be switched on with parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5991
5992
5993
5994
5995
5996
5997
5998    </tr>
5999
6000
6001
6002
6003
6004
6005 <tr>
6006
6007
6008
6009
6010
6011
6012 <td style="vertical-align: top;">
6013     
6014     
6015     
6016     
6017     
6018     
6019      <p><a name="initializing_actions"></a><b>initializing_actions</b></p>
6020
6021
6022
6023
6024
6025
6026
6027      </td>
6028
6029
6030
6031
6032
6033
6034 <td style="vertical-align: top;">C * 100</td>
6035
6036
6037
6038
6039
6040
6041
6042      <td style="vertical-align: top;"><br>
6043
6044
6045
6046
6047
6048
6049 </td>
6050
6051
6052
6053
6054
6055
6056 <td style="vertical-align: top;"> 
6057     
6058     
6059     
6060     
6061     
6062     
6063      <p style="font-style: normal;">Initialization actions
6064to be carried out.&nbsp; </p>
6065
6066
6067
6068
6069
6070
6071 
6072     
6073     
6074     
6075     
6076     
6077     
6078      <p style="font-style: normal;">This parameter does not have a
6079default value and therefore must be assigned with each model run. For
6080restart runs <b>initializing_actions</b> = <span style="font-style: italic;">'read_restart_data'</span>
6081must be set. For the initial run of a job chain the following values
6082are allowed:&nbsp; </p>
6083
6084
6085
6086
6087
6088
6089 
6090     
6091     
6092     
6093     
6094     
6095     
6096      <p style="font-style: normal;"><span style="font-style: italic;">'set_constant_profiles'</span>
6097      </p>
6098
6099
6100
6101
6102
6103
6104 
6105     
6106     
6107     
6108     
6109     
6110     
6111      <ul>
6112
6113
6114
6115
6116
6117
6118 
6119       
6120       
6121       
6122       
6123       
6124       
6125        <p>A horizontal wind profile consisting
6126of linear sections (see <a href="#ug_surface">ug_surface</a>,
6127        <a href="#ug_vertical_gradient">ug_vertical_gradient</a>,
6128        <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>
6129and <a href="#vg_surface">vg_surface</a>, <a href="#vg_vertical_gradient">vg_vertical_gradient</a>,
6130        <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
6131respectively) as well as a vertical temperature (humidity) profile
6132consisting of
6133linear sections (see <a href="#pt_surface">pt_surface</a>,
6134        <a href="#pt_vertical_gradient">pt_vertical_gradient</a>,
6135        <a href="#q_surface">q_surface</a>
6136and <a href="#q_vertical_gradient">q_vertical_gradient</a>)
6137are assumed as initial profiles. The subgrid-scale TKE is set to 0 but K<sub>m</sub>
6138and K<sub>h</sub> are set to very small values because
6139otherwise no TKE
6140would be generated.</p>
6141
6142
6143
6144
6145
6146
6147 
6148     
6149     
6150     
6151     
6152     
6153     
6154      </ul>
6155
6156
6157
6158
6159
6160
6161 
6162     
6163     
6164     
6165     
6166     
6167     
6168      <p style="font-style: italic;">'set_1d-model_profiles' </p>
6169
6170
6171
6172
6173
6174
6175
6176     
6177     
6178     
6179     
6180     
6181     
6182      <ul>
6183
6184
6185
6186
6187
6188
6189 
6190       
6191       
6192       
6193       
6194       
6195       
6196        <p>The arrays of the 3d-model are initialized with
6197the
6198(stationary) solution of the 1d-model. These are the variables e, kh,
6199km, u, v and with Prandtl layer switched on rif, us, usws, vsws. The
6200temperature (humidity) profile consisting of linear sections is set as
6201for 'set_constant_profiles' and assumed as constant in time within the
62021d-model. For steering of the 1d-model a set of parameters with suffix
6203"_1d" (e.g. <a href="#end_time_1d">end_time_1d</a>,
6204        <a href="#damp_level_1d">damp_level_1d</a>)
6205is available.</p>
6206
6207
6208
6209
6210
6211
6212 
6213     
6214     
6215     
6216     
6217     
6218     
6219      </ul>
6220
6221
6222
6223
6224
6225
6226 
6227     
6228     
6229     
6230     
6231     
6232     
6233      <p><span style="font-style: italic;">'by_user'</span></p>
6234
6235
6236
6237
6238
6239
6240     
6241     
6242     
6243     
6244     
6245     
6246      <p style="margin-left: 40px;">The initialization of the arrays
6247of the 3d-model is under complete control of the user and has to be
6248done in routine <a href="chapter_3.5.1.html#user_init_3d_model">user_init_3d_model</a>
6249of the user-interface.<span style="font-style: italic;"></span></p>
6250
6251
6252
6253
6254
6255
6256     
6257     
6258     
6259     
6260     
6261     
6262      <p><span style="font-style: italic;">'initialize_vortex'</span>
6263      </p>
6264
6265
6266
6267
6268
6269
6270 
6271     
6272     
6273     
6274     
6275     
6276     
6277      <div style="margin-left: 40px;">The initial
6278velocity field of the
62793d-model corresponds to a
6280Rankine-vortex with vertical axis. This setting may be used to test
6281advection 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>)
6282are necessary. In order not to distort the vortex, an initial
6283horizontal wind profile constant
6284with height is necessary (to be set by <b>initializing_actions</b>
6285= <span style="font-style: italic;">'set_constant_profiles'</span>)
6286and some other conditions have to be met (neutral stratification,
6287diffusion must be
6288switched off, see <a href="#km_constant">km_constant</a>).
6289The center of the vortex is located at jc = (nx+1)/2. It
6290extends from k = 0 to k = nz+1. Its radius is 8 * <a href="#dx">dx</a>
6291and the exponentially decaying part ranges to 32 * <a href="#dx">dx</a>
6292(see init_rankine.f90). </div>
6293
6294
6295
6296
6297
6298
6299 
6300     
6301     
6302     
6303     
6304     
6305     
6306      <p><span style="font-style: italic;">'initialize_ptanom'</span>
6307      </p>
6308
6309
6310
6311
6312
6313
6314 
6315     
6316     
6317     
6318     
6319     
6320     
6321      <ul>
6322
6323
6324
6325
6326
6327
6328 
6329       
6330       
6331       
6332       
6333       
6334       
6335        <p>A 2d-Gauss-like shape disturbance
6336(x,y) is added to the
6337initial temperature field with radius 10.0 * <a href="#dx">dx</a>
6338and center at jc = (nx+1)/2. This may be used for tests of scalar
6339advection schemes
6340(see <a href="#scalar_advec">scalar_advec</a>).
6341Such tests require a horizontal wind profile constant with hight and
6342diffusion
6343switched off (see <span style="font-style: italic;">'initialize_vortex'</span>).
6344Additionally, the buoyancy term
6345must be switched of in the equation of motion&nbsp; for w (this
6346requires the user to comment out the call of <span style="font-family: monospace;">buoyancy</span> in the
6347source code of <span style="font-family: monospace;">prognostic_equations.f90</span>).</p></ul>
6348
6349
6350
6351
6352
6353
6354 
6355     
6356     
6357     
6358     
6359     
6360     
6361      <p style="font-style: italic;">'cyclic_fill'</p><p style="font-style: normal; margin-left: 40px;">Here,
63623d-data from a precursor run are read by the initial (main) run. The
6363precursor run is allowed to have a smaller domain along x and y
6364compared with the main run. Also, different numbers of processors can
6365be used for these two runs. Limitations are that the precursor run must
6366use cyclic horizontal boundary conditions and that the number of vertical grid points, <a href="#nz">nz</a>, must be same for the precursor run and the main run. If the total domain of the main run is larger than that of the precursor
6367run, the domain is filled by cyclic repetition&nbsp;of the (cyclic)
6368precursor data. This initialization method is recommended if a
6369turbulent 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
6370combined, e.g. <b>initializing_actions</b> = <span style="font-style: italic;">'set_constant_profiles
6371initialize_vortex'</span>, but the values of <span style="font-style: italic;">'set_constant_profiles'</span>,
6372      <span style="font-style: italic;">'set_1d-model_profiles'</span>
6373, and <span style="font-style: italic;">'by_user'</span>
6374must not be given at the same time.</p>
6375
6376
6377
6378
6379
6380
6381 
6382     
6383     
6384     
6385     
6386     
6387     
6388     
6389
6390
6391
6392
6393
6394
6395 </td>
6396
6397
6398
6399
6400
6401
6402 </tr>
6403
6404
6405
6406
6407
6408
6409
6410    <tr>
6411
6412
6413
6414
6415
6416
6417 <td style="vertical-align: top;"> 
6418     
6419     
6420     
6421     
6422     
6423     
6424      <p><a name="km_constant"></a><b>km_constant</b></p>
6425
6426
6427
6428
6429
6430
6431
6432      </td>
6433
6434
6435
6436
6437
6438
6439 <td style="vertical-align: top;">R</td>
6440
6441
6442
6443
6444
6445
6446
6447      <td style="vertical-align: top;"><i>variable<br>
6448
6449
6450
6451
6452
6453
6454
6455(computed from TKE)</i></td>
6456
6457
6458
6459
6460
6461
6462 <td style="vertical-align: top;"> 
6463     
6464     
6465     
6466     
6467     
6468     
6469      <p>Constant eddy
6470diffusivities are used (laminar
6471simulations).&nbsp; </p>
6472
6473
6474
6475
6476
6477
6478 
6479     
6480     
6481     
6482     
6483     
6484     
6485      <p>If this parameter is
6486specified, both in the 1d and in the
64873d-model constant values for the eddy diffusivities are used in
6488space and time with K<sub>m</sub> = <b>km_constant</b>
6489and K<sub>h</sub> = K<sub>m</sub> / <a href="chapter_4.2.html#prandtl_number">prandtl_number</a>.
6490The prognostic equation for the subgrid-scale TKE is switched off.
6491Constant eddy diffusivities are only allowed with the Prandtl layer (<a href="#prandtl_layer">prandtl_layer</a>)
6492switched off.</p>
6493
6494
6495
6496
6497
6498
6499 </td>
6500
6501
6502
6503
6504
6505
6506 </tr>
6507
6508
6509
6510
6511
6512
6513 <tr>
6514
6515
6516
6517
6518
6519
6520 <td style="vertical-align: top;"> 
6521     
6522     
6523     
6524     
6525     
6526     
6527      <p><a name="km_damp_max"></a><b>km_damp_max</b></p>
6528
6529
6530
6531
6532
6533
6534
6535      </td>
6536
6537
6538
6539
6540
6541
6542 <td style="vertical-align: top;">R</td>
6543
6544
6545
6546
6547
6548
6549
6550      <td style="vertical-align: top;"><span style="font-style: italic;">0.5*(dx
6551or dy)</span></td>
6552
6553
6554
6555
6556
6557
6558 <td style="vertical-align: top;">Maximum
6559diffusivity used for filtering the velocity field in the vicinity of
6560the outflow (in m<sup>2</sup>/s).<br>
6561
6562
6563
6564
6565
6566
6567 <br>
6568
6569
6570
6571
6572
6573
6574
6575When using non-cyclic lateral boundaries (see <a href="#bc_lr">bc_lr</a>
6576or <a href="#bc_ns">bc_ns</a>),
6577a smoothing has to be applied to the
6578velocity field in the vicinity of the outflow in order to suppress any
6579reflections of outgoing disturbances. Smoothing is done by increasing
6580the eddy diffusivity along the horizontal direction which is
6581perpendicular to the outflow boundary. Only velocity components
6582parallel to the outflow boundary are filtered (e.g. v and w, if the
6583outflow is along x). Damping is applied from the bottom to the top of
6584the domain.<br>
6585
6586
6587
6588
6589
6590
6591 <br>
6592
6593
6594
6595
6596
6597
6598
6599The horizontal range of the smoothing is controlled by <a href="#outflow_damping_width">outflow_damping_width</a>
6600which defines the number of gridpoints (counted from the outflow
6601boundary) from where on the smoothing is applied. Starting from that
6602point, the eddy diffusivity is linearly increased (from zero to its
6603maximum value given by <span style="font-weight: bold;">km_damp_max</span>)
6604until half of the damping range width, from where it remains constant
6605up to the outflow boundary. If at a certain grid point the eddy
6606diffusivity calculated from the flow field is larger than as described
6607above, it is used instead.<br>
6608
6609
6610
6611
6612
6613
6614 <br>
6615
6616
6617
6618
6619
6620
6621
6622The default value of <span style="font-weight: bold;">km_damp_max</span>
6623has been empirically proven to be sufficient.</td>
6624
6625
6626
6627
6628
6629
6630 </tr>
6631
6632
6633
6634
6635
6636
6637 <tr>
6638
6639      <td style="vertical-align: top;"><a name="lad_surface"></a><span style="font-weight: bold;">lad_surface</span></td>
6640
6641      <td style="vertical-align: top;">R</td>
6642
6643      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
6644
6645      <td style="vertical-align: top;">Surface value of the leaf area density (in m<sup>2</sup>/m<sup>3</sup>).<br>
6646
6647      <br>
6648
6649This
6650parameter 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,
6651the leaf area density profile is constructed with <a href="#lad_vertical_gradient">lad_vertical_gradient</a>
6652and <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level
6653      </a>.</td>
6654
6655    </tr>
6656
6657    <tr>
6658
6659      <td style="vertical-align: top;"><a name="lad_vertical_gradient"></a><span style="font-weight: bold;">lad_vertical_gradient</span></td>
6660
6661      <td style="vertical-align: top;">R (10)</td>
6662
6663      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6664
6665      <td style="vertical-align: top;">Gradient(s) of the leaf area density (in&nbsp;m<sup>2</sup>/m<sup>4</sup>).<br>
6666
6667      <br>
6668
6669     
6670      <p>This leaf area density gradient
6671holds starting from the height&nbsp;
6672level defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6673(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>)
6674up 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
6675if <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>(1)
6676= <i>0.0</i>) can be assigned. The leaf area density at the surface is
6677assigned via <a href="#lad_surface">lad_surface</a>.&nbsp;
6678      </p>
6679
6680      </td>
6681
6682    </tr>
6683
6684    <tr>
6685
6686      <td style="vertical-align: top;"><a name="lad_vertical_gradient_level"></a><span style="font-weight: bold;">lad_vertical_gradient_level</span></td>
6687
6688      <td style="vertical-align: top;">R (10)</td>
6689
6690      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6691
6692      <td style="vertical-align: top;">Height level from which on the&nbsp;gradient
6693of the leaf area density defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6694is effective (in m).<br>
6695
6696      <br>
6697
6698The height levels have to be assigned in ascending order. The
6699default 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>
6700
6701    </tr>
6702
6703    <tr>
6704
6705      <td style="vertical-align: top;"><a name="leaf_surface_concentration"></a><b>leaf_surface_concentration</b></td>
6706
6707      <td style="vertical-align: top;">R</td>
6708
6709      <td style="vertical-align: top;"><i>0.0</i></td>
6710
6711      <td style="vertical-align: top;">Concentration of a passive scalar at the surface of a leaf (in K m/s).<br>
6712
6713
6714      <br>
6715
6716
6717This 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>.
6718The value of the concentration of a passive scalar at the surface of a
6719leaf is required for the parametrisation of the sources and sinks of
6720scalar concentration due to the canopy.</td>
6721
6722    </tr>
6723
6724    <tr>
6725
6726
6727
6728
6729
6730
6731
6732      <td style="vertical-align: top;"> 
6733     
6734     
6735     
6736     
6737     
6738     
6739      <p><a name="long_filter_factor"></a><b>long_filter_factor</b></p>
6740
6741
6742
6743
6744
6745
6746
6747      </td>
6748
6749
6750
6751
6752
6753
6754 <td style="vertical-align: top;">R</td>
6755
6756
6757
6758
6759
6760
6761
6762      <td style="vertical-align: top;"><i>0.0</i></td>
6763
6764
6765
6766
6767
6768
6769
6770      <td style="vertical-align: top;"> 
6771     
6772     
6773     
6774     
6775     
6776     
6777      <p>Filter factor
6778for the so-called Long-filter.<br>
6779
6780
6781
6782
6783
6784
6785 </p>
6786
6787
6788
6789
6790
6791
6792 
6793     
6794     
6795     
6796     
6797     
6798     
6799      <p><br>
6800
6801
6802
6803
6804
6805
6806
6807This filter very efficiently
6808eliminates 2-delta-waves sometimes cauesed by the upstream-spline
6809scheme (see Mahrer and
6810Pielke, 1978: Mon. Wea. Rev., 106, 818-830). It works in all three
6811directions in space. A value of <b>long_filter_factor</b>
6812= <i>0.01</i>
6813sufficiently removes the small-scale waves without affecting the
6814longer waves.<br>
6815
6816
6817
6818
6819
6820
6821 </p>
6822
6823
6824
6825
6826
6827
6828 
6829     
6830     
6831     
6832     
6833     
6834     
6835      <p>By default, the filter is
6836switched off (= <i>0.0</i>).
6837It is exclusively applied to the tendencies calculated by the
6838upstream-spline scheme (see <a href="#momentum_advec">momentum_advec</a>
6839and <a href="#scalar_advec">scalar_advec</a>),
6840not to the prognostic variables themselves. At the bottom and top
6841boundary of the model domain the filter effect for vertical
68422-delta-waves is reduced. There, the amplitude of these waves is only
6843reduced by approx. 50%, otherwise by nearly 100%.&nbsp; <br>
6844
6845
6846
6847
6848
6849
6850
6851Filter factors with values &gt; <i>0.01</i> also
6852reduce the amplitudes
6853of waves with wavelengths longer than 2-delta (see the paper by Mahrer
6854and
6855Pielke, quoted above). </p>
6856
6857
6858
6859
6860
6861
6862 </td>
6863
6864
6865
6866
6867
6868
6869 </tr>
6870
6871
6872
6873
6874
6875
6876 <tr>
6877
6878
6879
6880
6881
6882
6883      <td style="vertical-align: top;"><a name="loop_optimization"></a><span style="font-weight: bold;">loop_optimization</span></td>
6884
6885
6886
6887
6888
6889
6890      <td style="vertical-align: top;">C*16</td>
6891
6892
6893
6894
6895
6896
6897      <td style="vertical-align: top;"><span style="font-style: italic;">see right</span></td>
6898
6899
6900
6901
6902
6903
6904      <td>Method used to optimize loops for solving the prognostic equations .<br>
6905
6906
6907
6908
6909
6910
6911      <br>
6912
6913
6914
6915
6916
6917
6918By
6919default, the optimization method depends on the host on which PALM is
6920running. On machines with vector-type CPUs, single 3d-loops are used to
6921calculate each tendency term of each prognostic equation, while on all
6922other machines, all prognostic equations are solved within one big loop
6923over 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>
6924
6925
6926
6927
6928
6929
6930      <br>
6931
6932
6933
6934
6935
6936
6937The 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>
6938
6939
6940
6941
6942
6943
6944    </tr>
6945
6946
6947
6948
6949
6950
6951    <tr>
6952
6953
6954
6955
6956
6957
6958
6959      <td style="vertical-align: top;"><a name="mixing_length_1d"></a><span style="font-weight: bold;">mixing_length_1d</span><br>
6960
6961
6962
6963
6964
6965
6966
6967      </td>
6968
6969
6970
6971
6972
6973
6974 <td style="vertical-align: top;">C*20<br>
6975
6976
6977
6978
6979
6980
6981
6982      </td>
6983
6984
6985
6986
6987
6988
6989 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
6990
6991
6992
6993
6994
6995
6996 <span style="font-style: italic;">model'</span><br>
6997
6998
6999
7000
7001
7002
7003 </td>
7004
7005
7006
7007
7008
7009
7010
7011      <td style="vertical-align: top;">Mixing length used in the
70121d-model.<br>
7013
7014
7015
7016
7017
7018
7019 <br>
7020
7021
7022
7023
7024
7025
7026
7027By default the mixing length is calculated as in the 3d-model (i.e. it
7028depends on the grid spacing).<br>
7029
7030
7031
7032
7033
7034
7035 <br>
7036
7037
7038
7039
7040
7041
7042
7043By setting <span style="font-weight: bold;">mixing_length_1d</span>
7044= <span style="font-style: italic;">'blackadar'</span>,
7045the so-called Blackadar mixing length is used (l = kappa * z / ( 1 +
7046kappa * z / lambda ) with the limiting value lambda = 2.7E-4 * u_g / f).<br>
7047
7048
7049
7050
7051
7052
7053
7054      </td>
7055
7056
7057
7058
7059
7060
7061 </tr>
7062
7063
7064
7065
7066
7067
7068 
7069
7070
7071
7072
7073
7074
7075
7076    <tr>
7077
7078
7079
7080
7081
7082
7083 <td style="vertical-align: top;"> 
7084     
7085     
7086     
7087     
7088     
7089     
7090      <p><a name="momentum_advec"></a><b>momentum_advec</b></p>
7091
7092
7093
7094
7095
7096
7097
7098      </td>
7099
7100
7101
7102
7103
7104
7105 <td style="vertical-align: top;">C * 10</td>
7106
7107
7108
7109
7110
7111
7112
7113      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
7114
7115
7116
7117
7118
7119
7120
7121      <td style="vertical-align: top;"> 
7122     
7123     
7124     
7125     
7126     
7127     
7128      <p>Advection
7129scheme to be used for the momentum equations.<br>
7130
7131
7132
7133
7134
7135
7136 <br>
7137
7138
7139
7140
7141
7142
7143
7144The user can choose between the following schemes:<br>
7145
7146
7147
7148
7149
7150
7151
7152&nbsp;<br>
7153
7154
7155
7156
7157
7158
7159 <br>
7160
7161
7162
7163
7164
7165
7166 <span style="font-style: italic;">'pw-scheme'</span><br>
7167
7168
7169
7170
7171
7172
7173
7174      </p>
7175
7176
7177
7178
7179
7180
7181 
7182     
7183     
7184     
7185     
7186     
7187     
7188      <div style="margin-left: 40px;">The scheme of
7189Piascek and
7190Williams (1970, J. Comp. Phys., 6,
7191392-405) with central differences in the form C3 is used.<br>
7192
7193
7194
7195
7196
7197
7198
7199If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
7200= <span style="font-style: italic;">'leapfrog+euler'</span>
7201the
7202advection scheme is - for the Euler-timestep - automatically switched
7203to an upstream-scheme.<br>
7204
7205
7206
7207
7208
7209
7210 </div>
7211
7212
7213
7214
7215
7216
7217 
7218     
7219     
7220     
7221     
7222     
7223     
7224      <p> </p>
7225
7226
7227
7228
7229
7230
7231 
7232     
7233     
7234     
7235     
7236     
7237     
7238      <p><span style="font-style: italic;">'ups-scheme'</span><br>
7239
7240
7241
7242
7243
7244
7245
7246      </p>
7247
7248
7249
7250
7251
7252
7253 
7254     
7255     
7256     
7257     
7258     
7259     
7260      <div style="margin-left: 40px;">The
7261upstream-spline scheme is
7262used
7263(see Mahrer and Pielke,
72641978: Mon. Wea. Rev., 106, 818-830). In opposite to the
7265Piascek-Williams scheme, this is characterized by much better numerical
7266features (less numerical diffusion, better preservation of flow
7267structures, e.g. vortices), but computationally it is much more
7268expensive. In
7269addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
7270= <span style="font-style: italic;">'</span><i>euler'</i>),
7271i.e. the
7272timestep accuracy is only of first order.
7273For this reason the advection of scalar variables (see <a href="#scalar_advec">scalar_advec</a>)
7274should then also be carried out with the upstream-spline scheme,
7275because otherwise the scalar variables would
7276be subject to large numerical diffusion due to the upstream
7277scheme.&nbsp; </div>
7278
7279
7280
7281
7282
7283
7284 
7285     
7286     
7287     
7288     
7289     
7290     
7291      <p style="margin-left: 40px;">Since
7292the cubic splines used tend
7293to overshoot under
7294certain circumstances, this effect must be adjusted by suitable
7295filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
7296      <a href="#long_filter_factor">long_filter_factor</a>,
7297      <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>).
7298This is always neccessary for runs with stable stratification,
7299even if this stratification appears only in parts of the model domain.<br>
7300
7301
7302
7303
7304
7305
7306
7307      </p>
7308
7309
7310
7311
7312
7313
7314 
7315     
7316     
7317     
7318     
7319     
7320     
7321      <div style="margin-left: 40px;">With stable
7322stratification the
7323upstream-spline scheme also
7324produces gravity waves with large amplitude, which must be
7325suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
7326
7327
7328
7329
7330
7331
7332
7333      <br>
7334
7335
7336
7337
7338
7339
7340 <span style="font-weight: bold;">Important: </span>The&nbsp;
7341upstream-spline scheme is not implemented for humidity and passive
7342scalars (see&nbsp;<a href="#humidity">humidity</a>
7343and <a href="#passive_scalar">passive_scalar</a>)
7344and requires the use of a 2d-domain-decomposition. The last conditions
7345severely restricts code optimization on several machines leading to
7346very long execution times! The scheme is also not allowed for
7347non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
7348and <a href="#bc_ns">bc_ns</a>).</div>
7349
7350
7351
7352
7353
7354
7355 </td>
7356
7357
7358
7359
7360
7361
7362
7363    </tr>
7364
7365
7366
7367
7368
7369
7370 <tr>
7371
7372
7373
7374
7375
7376
7377 <td style="vertical-align: top;"><a name="netcdf_precision"></a><span style="font-weight: bold;">netcdf_precision</span><br>
7378
7379
7380
7381
7382
7383
7384
7385      </td>
7386
7387
7388
7389
7390
7391
7392 <td style="vertical-align: top;">C*20<br>
7393
7394
7395
7396
7397
7398
7399
7400(10)<br>
7401
7402
7403
7404
7405
7406
7407 </td>
7408
7409
7410
7411
7412
7413
7414 <td style="vertical-align: top;"><span style="font-style: italic;">single preci-</span><br style="font-style: italic;">
7415
7416
7417
7418
7419
7420
7421 <span style="font-style: italic;">sion for all</span><br style="font-style: italic;">
7422
7423
7424
7425
7426
7427
7428 <span style="font-style: italic;">output quan-</span><br style="font-style: italic;">
7429
7430
7431
7432
7433
7434
7435 <span style="font-style: italic;">tities</span><br>
7436
7437
7438
7439
7440
7441
7442 </td>
7443
7444
7445
7446
7447
7448
7449
7450      <td style="vertical-align: top;">Defines the accuracy of
7451the NetCDF output.<br>
7452
7453
7454
7455
7456
7457
7458 <br>
7459
7460
7461
7462
7463
7464
7465
7466By default, all NetCDF output data (see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
7467have single precision&nbsp; (4 byte) accuracy. Double precision (8
7468byte) can be choosen alternatively.<br>
7469
7470
7471
7472
7473
7474
7475
7476Accuracy for the different output data (cross sections, 3d-volume data,
7477spectra, etc.) can be set independently.<br>
7478
7479
7480
7481
7482
7483
7484 <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL4'</span>
7485(single precision) or <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL8'</span>
7486(double precision) are the two principally allowed values for <span style="font-weight: bold;">netcdf_precision</span>,
7487where the string <span style="font-style: italic;">'&lt;out&gt;'
7488      </span>can be chosen out of the following list:<br>
7489
7490
7491
7492
7493
7494
7495 <br>
7496
7497
7498
7499
7500
7501
7502
7503     
7504     
7505     
7506     
7507     
7508     
7509      <table style="text-align: left; width: 284px; height: 234px;" border="1" cellpadding="2" cellspacing="2">
7510
7511
7512
7513
7514
7515
7516 <tbody>
7517
7518
7519
7520
7521
7522
7523
7524          <tr>
7525
7526
7527
7528
7529
7530
7531 <td style="vertical-align: top;"><span style="font-style: italic;">'xy'</span><br>
7532
7533
7534
7535
7536
7537
7538 </td>
7539
7540
7541
7542
7543
7544
7545
7546            <td style="vertical-align: top;">horizontal cross section<br>
7547
7548
7549
7550
7551
7552
7553
7554            </td>
7555
7556
7557
7558
7559
7560
7561 </tr>
7562
7563
7564
7565
7566
7567
7568 <tr>
7569
7570
7571
7572
7573
7574
7575 <td style="vertical-align: top;"><span style="font-style: italic;">'xz'</span><br>
7576
7577
7578
7579
7580
7581
7582 </td>
7583
7584
7585
7586
7587
7588
7589
7590            <td style="vertical-align: top;">vertical (xz) cross
7591section<br>
7592
7593
7594
7595
7596
7597
7598 </td>
7599
7600
7601
7602
7603
7604
7605 </tr>
7606
7607
7608
7609
7610
7611
7612 <tr>
7613
7614
7615
7616
7617
7618
7619 <td style="vertical-align: top;"><span style="font-style: italic;">'yz'</span><br>
7620
7621
7622
7623
7624
7625
7626 </td>
7627
7628
7629
7630
7631
7632
7633
7634            <td style="vertical-align: top;">vertical (yz) cross
7635section<br>
7636
7637
7638
7639
7640
7641
7642 </td>
7643
7644
7645
7646
7647
7648
7649 </tr>
7650
7651
7652
7653
7654
7655
7656 <tr>
7657
7658
7659
7660
7661
7662
7663 <td style="vertical-align: top;"><span style="font-style: italic;">'2d'</span><br>
7664
7665
7666
7667
7668
7669
7670 </td>
7671
7672
7673
7674
7675
7676
7677
7678            <td style="vertical-align: top;">all cross sections<br>
7679
7680
7681
7682
7683
7684
7685
7686            </td>
7687
7688
7689
7690
7691
7692
7693 </tr>
7694
7695
7696
7697
7698
7699
7700 <tr>
7701
7702
7703
7704
7705
7706
7707 <td style="vertical-align: top;"><span style="font-style: italic;">'3d'</span><br>
7708
7709
7710
7711
7712
7713
7714 </td>
7715
7716
7717
7718
7719
7720
7721
7722            <td style="vertical-align: top;">volume data<br>
7723
7724
7725
7726
7727
7728
7729 </td>
7730
7731
7732
7733
7734
7735
7736
7737          </tr>
7738
7739
7740
7741
7742
7743
7744 <tr>
7745
7746
7747
7748
7749
7750
7751 <td style="vertical-align: top;"><span style="font-style: italic;">'pr'</span><br>
7752
7753
7754
7755
7756
7757
7758 </td>
7759
7760
7761
7762
7763
7764
7765
7766            <td style="vertical-align: top;">vertical profiles<br>
7767
7768
7769
7770
7771
7772
7773
7774            </td>
7775
7776
7777
7778
7779
7780
7781 </tr>
7782
7783
7784
7785
7786
7787
7788 <tr>
7789
7790
7791
7792
7793
7794
7795 <td style="vertical-align: top;"><span style="font-style: italic;">'ts'</span><br>
7796
7797
7798
7799
7800
7801
7802 </td>
7803
7804
7805
7806
7807
7808
7809
7810            <td style="vertical-align: top;">time series, particle
7811time series<br>
7812
7813
7814
7815
7816
7817
7818 </td>
7819
7820
7821
7822
7823
7824
7825 </tr>
7826
7827
7828
7829
7830
7831
7832 <tr>
7833
7834
7835
7836
7837
7838
7839 <td style="vertical-align: top;"><span style="font-style: italic;">'sp'</span><br>
7840
7841
7842
7843
7844
7845
7846 </td>
7847
7848
7849
7850
7851
7852
7853
7854            <td style="vertical-align: top;">spectra<br>
7855
7856
7857
7858
7859
7860
7861 </td>
7862
7863
7864
7865
7866
7867
7868
7869          </tr>
7870
7871
7872
7873
7874
7875
7876 <tr>
7877
7878
7879
7880
7881
7882
7883 <td style="vertical-align: top;"><span style="font-style: italic;">'prt'</span><br>
7884
7885
7886
7887
7888
7889
7890 </td>
7891
7892
7893
7894
7895
7896
7897
7898            <td style="vertical-align: top;">particles<br>
7899
7900
7901
7902
7903
7904
7905 </td>
7906
7907
7908
7909
7910
7911
7912
7913          </tr>
7914
7915
7916
7917
7918
7919
7920 <tr>
7921
7922
7923
7924
7925
7926
7927 <td style="vertical-align: top;"><span style="font-style: italic;">'all'</span><br>
7928
7929
7930
7931
7932
7933
7934 </td>
7935
7936
7937
7938
7939
7940
7941
7942            <td style="vertical-align: top;">all output quantities<br>
7943
7944
7945
7946
7947
7948
7949
7950            </td>
7951
7952
7953
7954
7955
7956
7957 </tr>
7958
7959
7960
7961
7962
7963
7964 
7965       
7966       
7967       
7968       
7969       
7970       
7971        </tbody> 
7972     
7973     
7974     
7975     
7976     
7977     
7978      </table>
7979
7980
7981
7982
7983
7984
7985 <br>
7986
7987
7988
7989
7990
7991
7992 <span style="font-weight: bold;">Example:</span><br>
7993
7994
7995
7996
7997
7998
7999
8000If all cross section data and the particle data shall be output in
8001double 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>
8002has to be assigned.<br>
8003
8004
8005
8006
8007
8008
8009 </td>
8010
8011
8012
8013
8014
8015
8016 </tr>
8017
8018
8019
8020
8021
8022
8023
8024   
8025
8026
8027
8028
8029
8030
8031 
8032
8033
8034
8035
8036
8037
8038
8039    <tr>
8040
8041
8042
8043
8044
8045
8046 <td style="vertical-align: top;"> 
8047     
8048     
8049     
8050     
8051     
8052     
8053      <p><a name="nsor_ini"></a><b>nsor_ini</b></p>
8054
8055
8056
8057
8058
8059
8060
8061      </td>
8062
8063
8064
8065
8066
8067
8068 <td style="vertical-align: top;">I</td>
8069
8070
8071
8072
8073
8074
8075
8076      <td style="vertical-align: top;"><i>100</i></td>
8077
8078
8079
8080
8081
8082
8083
8084      <td style="vertical-align: top;"> 
8085     
8086     
8087     
8088     
8089     
8090     
8091      <p>Initial number
8092of iterations with the SOR algorithm.&nbsp; </p>
8093
8094
8095
8096
8097
8098
8099 
8100     
8101     
8102     
8103     
8104     
8105     
8106      <p>This
8107parameter is only effective if the SOR algorithm was
8108selected as the pressure solver scheme (<a href="chapter_4.2.html#psolver">psolver</a>
8109= <span style="font-style: italic;">'sor'</span>)
8110and specifies the
8111number of initial iterations of the SOR
8112scheme (at t = 0). The number of subsequent iterations at the following
8113timesteps is determined
8114with the parameter <a href="#nsor">nsor</a>.
8115Usually <b>nsor</b> &lt; <b>nsor_ini</b>,
8116since in each case
8117subsequent calls to <a href="chapter_4.2.html#psolver">psolver</a>
8118use the solution of the previous call as initial value. Suitable
8119test runs should determine whether sufficient convergence of the
8120solution is obtained with the default value and if necessary the value
8121of <b>nsor_ini</b> should be changed.</p>
8122
8123
8124
8125
8126
8127
8128 </td>
8129
8130
8131
8132
8133
8134
8135
8136    </tr>
8137
8138
8139
8140
8141
8142
8143 <tr>
8144
8145
8146
8147
8148
8149
8150 <td style="vertical-align: top;">
8151     
8152     
8153     
8154     
8155     
8156     
8157      <p><a name="nx"></a><b>nx</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 x-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 i = 0, the actual number of grid points is equal to <b>nx+1</b>.
8220In case of cyclic boundary conditions along x, the domain size is (<b>nx+1</b>)*
8221      <a href="#dx">dx</a>.</p>
8222
8223
8224
8225
8226
8227
8228 
8229     
8230     
8231     
8232     
8233     
8234     
8235      <p>For
8236parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8237= <span style="font-style: italic;">'strict'</span>,
8238      <b>nx+1</b> must
8239be an integral multiple
8240of the processor numbers (see <a href="#npex">npex</a>
8241and <a href="#npey">npey</a>)
8242along x- as well as along y-direction (due to data
8243transposition restrictions).</p>
8244
8245
8246
8247
8248
8249
8250     
8251     
8252     
8253     
8254     
8255     
8256      <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>
8257and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8258
8259
8260
8261
8262
8263
8264 </td>
8265
8266
8267
8268
8269
8270
8271 </tr>
8272
8273
8274
8275
8276
8277
8278 <tr>
8279
8280
8281
8282
8283
8284
8285
8286      <td style="vertical-align: top;"> 
8287     
8288     
8289     
8290     
8291     
8292     
8293      <p><a name="ny"></a><b>ny</b></p>
8294
8295
8296
8297
8298
8299
8300
8301      </td>
8302
8303
8304
8305
8306
8307
8308 <td style="vertical-align: top;">I</td>
8309
8310
8311
8312
8313
8314
8315
8316      <td style="vertical-align: top;"><br>
8317
8318
8319
8320
8321
8322
8323 </td>
8324
8325
8326
8327
8328
8329
8330 <td style="vertical-align: top;"> 
8331     
8332     
8333     
8334     
8335     
8336     
8337      <p>Number of grid
8338points in y-direction.&nbsp; </p>
8339
8340
8341
8342
8343
8344
8345 
8346     
8347     
8348     
8349     
8350     
8351     
8352      <p>A value for this
8353parameter must be assigned. Since the lower
8354array bound in PALM starts with j = 0, the actual number of grid points
8355is equal to <b>ny+1</b>. In case of cyclic boundary
8356conditions along
8357y, the domain size is (<b>ny+1</b>) * <a href="#dy">dy</a>.</p>
8358
8359
8360
8361
8362
8363
8364
8365     
8366     
8367     
8368     
8369     
8370     
8371      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8372= <span style="font-style: italic;">'strict'</span>,
8373      <b>ny+1</b> must
8374be an integral multiple
8375of the processor numbers (see <a href="#npex">npex</a>
8376and <a href="#npey">npey</a>)&nbsp;
8377along y- as well as along x-direction (due to data
8378transposition restrictions).</p>
8379
8380
8381
8382
8383
8384
8385     
8386     
8387     
8388     
8389     
8390     
8391      <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>
8392and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8393
8394
8395
8396
8397
8398
8399 </td>
8400
8401
8402
8403
8404
8405
8406 </tr>
8407
8408
8409
8410
8411
8412
8413 <tr>
8414
8415
8416
8417
8418
8419
8420
8421      <td style="vertical-align: top;"> 
8422     
8423     
8424     
8425     
8426     
8427     
8428      <p><a name="nz"></a><b>nz</b></p>
8429
8430
8431
8432
8433
8434
8435
8436      </td>
8437
8438
8439
8440
8441
8442
8443 <td style="vertical-align: top;">I</td>
8444
8445
8446
8447
8448
8449
8450
8451      <td style="vertical-align: top;"><br>
8452
8453
8454
8455
8456
8457
8458 </td>
8459
8460
8461
8462
8463
8464
8465 <td style="vertical-align: top;"> 
8466     
8467     
8468     
8469     
8470     
8471     
8472      <p>Number of grid
8473points in z-direction.&nbsp; </p>
8474
8475
8476
8477
8478
8479
8480 
8481     
8482     
8483     
8484     
8485     
8486     
8487      <p>A value for this
8488parameter must be assigned. Since the lower
8489array bound in PALM
8490starts with k = 0 and since one additional grid point is added at the
8491top boundary (k = <b>nz+1</b>), the actual number of grid
8492points is <b>nz+2</b>.
8493However, the prognostic equations are only solved up to <b>nz</b>
8494(u,
8495v)
8496or up to <b>nz-1</b> (w, scalar quantities). The top
8497boundary for u
8498and v is at k = <b>nz+1</b> (u, v) while at k = <b>nz</b>
8499for all
8500other quantities.&nbsp; </p>
8501
8502
8503
8504
8505
8506
8507 
8508     
8509     
8510     
8511     
8512     
8513     
8514      <p>For parallel
8515runs,&nbsp; in case of <a href="#grid_matching">grid_matching</a>
8516= <span style="font-style: italic;">'strict'</span>,
8517      <b>nz</b> must
8518be an integral multiple of
8519the number of processors in x-direction (due to data transposition
8520restrictions).</p>
8521
8522
8523
8524
8525
8526
8527 </td>
8528
8529
8530
8531
8532
8533
8534 </tr>
8535
8536
8537
8538
8539
8540
8541 <tr>
8542
8543
8544
8545
8546
8547
8548      <td style="vertical-align: top;"><a name="ocean"></a><span style="font-weight: bold;">ocean</span></td>
8549
8550
8551
8552
8553
8554
8555      <td style="vertical-align: top;">L</td>
8556
8557
8558
8559
8560
8561
8562      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
8563
8564
8565
8566
8567
8568
8569      <td style="vertical-align: top;">Parameter to switch on&nbsp;ocean runs.<br>
8570
8571
8572
8573
8574
8575
8576      <br>
8577
8578
8579
8580
8581
8582
8583By 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>
8584
8585
8586
8587
8588
8589
8590      <br>
8591
8592
8593
8594
8595
8596
8597     
8598     
8599     
8600     
8601     
8602     
8603      <ul>
8604
8605
8606
8607
8608
8609
8610        <li>An additional prognostic equation for salinity is solved.</li>
8611
8612
8613
8614
8615
8616
8617        <li>Potential temperature in buoyancy and stability-related terms is replaced by potential density.</li>
8618
8619
8620
8621
8622
8623
8624        <li>Potential
8625density is calculated from the equation of state for seawater after
8626each timestep, using the algorithm proposed by Jackett et al. (2006, J.
8627Atmos. Oceanic Technol., <span style="font-weight: bold;">23</span>, 1709-1728).<br>
8628
8629
8630
8631
8632
8633
8634So far, only the initial hydrostatic pressure is entered into this equation.</li>
8635
8636
8637
8638
8639
8640
8641        <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>
8642
8643
8644
8645
8646
8647
8648        <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>
8649
8650
8651
8652
8653
8654
8655        <li>Zero salinity flux is used as default boundary condition at the bottom of the sea.</li>
8656
8657
8658
8659
8660
8661
8662        <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>
8663
8664
8665
8666
8667
8668
8669     
8670     
8671     
8672     
8673     
8674     
8675      </ul>
8676
8677
8678
8679
8680
8681
8682      <br>
8683
8684
8685
8686
8687
8688
8689Relevant 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>
8690
8691
8692
8693
8694
8695
8696      <br>
8697
8698
8699
8700
8701
8702
8703Section <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>
8704
8705
8706
8707
8708
8709
8710      <br>
8711
8712
8713
8714
8715
8716
8717      <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>
8718
8719
8720
8721      </td>
8722
8723
8724
8725
8726
8727
8728    </tr>
8729
8730
8731
8732
8733
8734
8735    <tr>
8736
8737
8738
8739
8740
8741
8742 <td style="vertical-align: top;"> 
8743     
8744     
8745     
8746     
8747     
8748     
8749      <p><a name="omega"></a><b>omega</b></p>
8750
8751
8752
8753
8754
8755
8756
8757      </td>
8758
8759
8760
8761
8762
8763
8764 <td style="vertical-align: top;">R</td>
8765
8766
8767
8768
8769
8770
8771
8772      <td style="vertical-align: top;"><i>7.29212E-5</i></td>
8773
8774
8775
8776
8777
8778
8779
8780      <td style="vertical-align: top;"> 
8781     
8782     
8783     
8784     
8785     
8786     
8787      <p>Angular
8788velocity of the rotating system (in rad s<sup>-1</sup>).&nbsp;
8789      </p>
8790
8791
8792
8793
8794
8795
8796 
8797     
8798     
8799     
8800     
8801     
8802     
8803      <p>The angular velocity of the earth is set by
8804default. The
8805values
8806of the Coriolis parameters are calculated as:&nbsp; </p>
8807
8808
8809
8810
8811
8812
8813 
8814     
8815     
8816     
8817     
8818     
8819     
8820      <ul>
8821
8822
8823
8824
8825
8826
8827
8828       
8829       
8830       
8831       
8832       
8833       
8834        <p>f = 2.0 * <b>omega</b> * sin(<a href="#phi">phi</a>)&nbsp;
8835        <br>
8836
8837
8838
8839
8840
8841
8842f* = 2.0 * <b>omega</b> * cos(<a href="#phi">phi</a>)</p>
8843
8844
8845
8846
8847
8848
8849
8850     
8851     
8852     
8853     
8854     
8855     
8856      </ul>
8857
8858
8859
8860
8861
8862
8863 </td>
8864
8865
8866
8867
8868
8869
8870 </tr>
8871
8872
8873
8874
8875
8876
8877 <tr>
8878
8879
8880
8881
8882
8883
8884 <td style="vertical-align: top;"> 
8885     
8886     
8887     
8888     
8889     
8890     
8891      <p><a name="outflow_damping_width"></a><b>outflow_damping_width</b></p>
8892
8893
8894
8895
8896
8897
8898
8899      </td>
8900
8901
8902
8903
8904
8905
8906 <td style="vertical-align: top;">I</td>
8907
8908
8909
8910
8911
8912
8913
8914      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(20,
8915nx/2</span> or <span style="font-style: italic;">ny/2)</span></td>
8916
8917
8918
8919
8920
8921
8922
8923      <td style="vertical-align: top;">Width of
8924the damping range in the vicinity of the outflow (gridpoints).<br>
8925
8926
8927
8928
8929
8930
8931
8932      <br>
8933
8934
8935
8936
8937
8938
8939
8940When using non-cyclic lateral boundaries (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
8941or <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
8942a smoothing has to be applied to the
8943velocity field in the vicinity of the outflow in order to suppress any
8944reflections of outgoing disturbances. This parameter controlls the
8945horizontal range to which the smoothing is applied. The range is given
8946in gridpoints counted from the respective outflow boundary. For further
8947details about the smoothing see parameter <a href="chapter_4.1.html#km_damp_max">km_damp_max</a>,
8948which defines the magnitude of the damping.</td>
8949
8950
8951
8952
8953
8954
8955 </tr>
8956
8957
8958
8959
8960
8961
8962
8963    <tr>
8964
8965
8966
8967
8968
8969
8970 <td style="vertical-align: top;"> 
8971     
8972     
8973     
8974     
8975     
8976     
8977      <p><a name="overshoot_limit_e"></a><b>overshoot_limit_e</b></p>
8978
8979
8980
8981
8982
8983
8984
8985      </td>
8986
8987
8988
8989
8990
8991
8992 <td style="vertical-align: top;">R</td>
8993
8994
8995
8996
8997
8998
8999
9000      <td style="vertical-align: top;"><i>0.0</i></td>
9001
9002
9003
9004
9005
9006
9007
9008      <td style="vertical-align: top;"> 
9009     
9010     
9011     
9012     
9013     
9014     
9015      <p>Allowed limit
9016for the overshooting of subgrid-scale TKE in
9017case that the upstream-spline scheme is switched on (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
9018      </p>
9019
9020
9021
9022
9023
9024
9025 
9026     
9027     
9028     
9029     
9030     
9031     
9032      <p>By deafult, if cut-off of overshoots is switched
9033on for the
9034upstream-spline scheme (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>),
9035no overshoots are permitted at all. If <b>overshoot_limit_e</b>
9036is given a non-zero value, overshoots with the respective
9037amplitude (both upward and downward) are allowed.&nbsp; </p>
9038
9039
9040
9041
9042
9043
9044
9045     
9046     
9047     
9048     
9049     
9050     
9051      <p>Only positive values are allowed for <b>overshoot_limit_e</b>.</p>
9052
9053
9054
9055
9056
9057
9058
9059      </td>
9060
9061
9062
9063
9064
9065
9066 </tr>
9067
9068
9069
9070
9071
9072
9073 <tr>
9074
9075
9076
9077
9078
9079
9080 <td style="vertical-align: top;"> 
9081     
9082     
9083     
9084     
9085     
9086     
9087      <p><a name="overshoot_limit_pt"></a><b>overshoot_limit_pt</b></p>
9088
9089
9090
9091
9092
9093
9094
9095      </td>
9096
9097
9098
9099
9100
9101
9102 <td style="vertical-align: top;">R</td>
9103
9104
9105
9106
9107
9108
9109
9110      <td style="vertical-align: top;"><i>0.0</i></td>
9111
9112
9113
9114
9115
9116
9117
9118      <td style="vertical-align: top;"> 
9119     
9120     
9121     
9122     
9123     
9124     
9125      <p>Allowed limit
9126for the overshooting of potential temperature in
9127case that the upstream-spline scheme is switched on (in K).&nbsp; </p>
9128
9129
9130
9131
9132
9133
9134
9135     
9136     
9137     
9138     
9139     
9140     
9141      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9142      </p>
9143
9144
9145
9146
9147
9148
9149 
9150     
9151     
9152     
9153     
9154     
9155     
9156      <p>Only positive values are allowed for <b>overshoot_limit_pt</b>.</p>
9157
9158
9159
9160
9161
9162
9163
9164      </td>
9165
9166
9167
9168
9169
9170
9171 </tr>
9172
9173
9174
9175
9176
9177
9178 <tr>
9179
9180
9181
9182
9183
9184
9185 <td style="vertical-align: top;"> 
9186     
9187     
9188     
9189     
9190     
9191     
9192      <p><a name="overshoot_limit_u"></a><b>overshoot_limit_u</b></p>
9193
9194
9195
9196
9197
9198
9199
9200      </td>
9201
9202
9203
9204
9205
9206
9207 <td style="vertical-align: top;">R</td>
9208
9209
9210
9211
9212
9213
9214
9215      <td style="vertical-align: top;"><i>0.0</i></td>
9216
9217
9218
9219
9220
9221
9222
9223      <td style="vertical-align: top;">Allowed limit for the
9224overshooting of
9225the u-component of velocity in case that the upstream-spline scheme is
9226switched on (in m/s).
9227     
9228     
9229     
9230     
9231     
9232     
9233      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9234      </p>
9235
9236
9237
9238
9239
9240
9241 
9242     
9243     
9244     
9245     
9246     
9247     
9248      <p>Only positive values are allowed for <b>overshoot_limit_u</b>.</p>
9249
9250
9251
9252
9253
9254
9255
9256      </td>
9257
9258
9259
9260
9261
9262
9263 </tr>
9264
9265
9266
9267
9268
9269
9270 <tr>
9271
9272
9273
9274
9275
9276
9277 <td style="vertical-align: top;"> 
9278     
9279     
9280     
9281     
9282     
9283     
9284      <p><a name="overshoot_limit_v"></a><b>overshoot_limit_v</b></p>
9285
9286
9287
9288
9289
9290
9291
9292      </td>
9293
9294
9295
9296
9297
9298
9299 <td style="vertical-align: top;">R</td>
9300
9301
9302
9303
9304
9305
9306
9307      <td style="vertical-align: top;"><i>0.0</i></td>
9308
9309
9310
9311
9312
9313
9314
9315      <td style="vertical-align: top;"> 
9316     
9317     
9318     
9319     
9320     
9321     
9322      <p>Allowed limit
9323for the overshooting of the v-component of
9324velocity in case that the upstream-spline scheme is switched on
9325(in m/s).&nbsp; </p>
9326
9327
9328
9329
9330
9331
9332 
9333     
9334     
9335     
9336     
9337     
9338     
9339      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9340      </p>
9341
9342
9343
9344
9345
9346
9347 
9348     
9349     
9350     
9351     
9352     
9353     
9354      <p>Only positive values are allowed for <b>overshoot_limit_v</b>.</p>
9355
9356
9357
9358
9359
9360
9361
9362      </td>
9363
9364
9365
9366
9367
9368
9369 </tr>
9370
9371
9372
9373
9374
9375
9376 <tr>
9377
9378
9379
9380
9381
9382
9383 <td style="vertical-align: top;"> 
9384     
9385     
9386     
9387     
9388     
9389     
9390      <p><a name="overshoot_limit_w"></a><b>overshoot_limit_w</b></p>
9391
9392
9393
9394
9395
9396
9397
9398      </td>
9399
9400
9401
9402
9403
9404
9405 <td style="vertical-align: top;">R</td>
9406
9407
9408
9409
9410
9411
9412
9413      <td style="vertical-align: top;"><i>0.0</i></td>
9414
9415
9416
9417
9418
9419
9420
9421      <td style="vertical-align: top;"> 
9422     
9423     
9424     
9425     
9426     
9427     
9428      <p>Allowed limit
9429for the overshooting of the w-component of
9430velocity in case that the upstream-spline scheme is switched on
9431(in m/s).&nbsp; </p>
9432
9433
9434
9435
9436
9437
9438 
9439     
9440     
9441     
9442     
9443     
9444     
9445      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9446      </p>
9447
9448
9449
9450
9451
9452
9453 
9454     
9455     
9456     
9457     
9458     
9459     
9460      <p>Only positive values are permitted for <b>overshoot_limit_w</b>.</p>
9461
9462
9463
9464
9465
9466
9467
9468      </td>
9469
9470
9471
9472
9473
9474
9475 </tr>
9476
9477
9478
9479
9480
9481
9482 <tr>
9483
9484
9485
9486
9487
9488
9489 <td style="vertical-align: top;"> 
9490     
9491     
9492     
9493     
9494     
9495     
9496      <p><a name="passive_scalar"></a><b>passive_scalar</b></p>
9497
9498
9499
9500
9501
9502
9503
9504      </td>
9505
9506
9507
9508
9509
9510
9511 <td style="vertical-align: top;">L</td>
9512
9513
9514
9515
9516
9517
9518
9519      <td style="vertical-align: top;"><i>.F.</i></td>
9520
9521
9522
9523
9524
9525
9526
9527      <td style="vertical-align: top;"> 
9528     
9529     
9530     
9531     
9532     
9533     
9534      <p>Parameter to
9535switch on the prognostic equation for a passive
9536scalar. <br>
9537
9538
9539
9540
9541
9542
9543 </p>
9544
9545
9546
9547
9548
9549
9550 
9551     
9552     
9553     
9554     
9555     
9556     
9557      <p>The initial vertical profile
9558of s can be set via parameters <a href="#s_surface">s_surface</a>,
9559      <a href="#s_vertical_gradient">s_vertical_gradient</a>
9560and&nbsp; <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.
9561Boundary conditions can be set via <a href="#s_surface_initial_change">s_surface_initial_change</a>
9562and <a href="#surface_scalarflux">surface_scalarflux</a>.&nbsp;
9563      </p>
9564
9565
9566
9567
9568
9569
9570 
9571     
9572     
9573     
9574     
9575     
9576     
9577      <p><b>Note:</b> <br>
9578
9579
9580
9581
9582
9583
9584
9585With <span style="font-weight: bold;">passive_scalar</span>
9586switched
9587on, the simultaneous use of humidity (see&nbsp;<a href="#humidity">humidity</a>)
9588is impossible.</p>
9589
9590
9591
9592
9593
9594
9595 </td>
9596
9597
9598
9599
9600
9601
9602 </tr>
9603
9604
9605
9606
9607
9608
9609 <tr>
9610
9611      <td style="vertical-align: top;"><a name="pch_index"></a><span style="font-weight: bold;">pch_index</span></td>
9612
9613      <td style="vertical-align: top;">I</td>
9614
9615      <td style="vertical-align: top;"><span style="font-style: italic;">0</span></td>
9616
9617      <td style="vertical-align: top;">Grid point index (scalar) of the upper boundary of the plant canopy layer.<br>
9618
9619      <br>
9620
9621Above <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>
9622
9623    </tr>
9624
9625    <tr>
9626
9627
9628
9629
9630
9631
9632 <td style="vertical-align: top;"> 
9633     
9634     
9635     
9636     
9637     
9638     
9639      <p><a name="phi"></a><b>phi</b></p>
9640
9641
9642
9643
9644
9645
9646
9647      </td>
9648
9649
9650
9651
9652
9653
9654 <td style="vertical-align: top;">R</td>
9655
9656
9657
9658
9659
9660
9661
9662      <td style="vertical-align: top;"><i>55.0</i></td>
9663
9664
9665
9666
9667
9668
9669
9670      <td style="vertical-align: top;"> 
9671     
9672     
9673     
9674     
9675     
9676     
9677      <p>Geographical
9678latitude (in degrees).&nbsp; </p>
9679
9680
9681
9682
9683
9684
9685 
9686     
9687     
9688     
9689     
9690     
9691     
9692      <p>The value of
9693this parameter determines the value of the
9694Coriolis parameters f and f*, provided that the angular velocity (see <a href="#omega">omega</a>)
9695is non-zero.</p>
9696
9697
9698
9699
9700
9701
9702 </td>
9703
9704
9705
9706
9707
9708
9709 </tr>
9710
9711
9712
9713
9714
9715
9716 <tr>
9717
9718      <td style="vertical-align: top;"><a name="plant_canopy"></a><span style="font-weight: bold;">plant_canopy</span></td>
9719
9720      <td style="vertical-align: top;">L</td>
9721
9722      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9723
9724      <td style="vertical-align: top;">Switch for the plant_canopy_model.<br>
9725
9726      <br>
9727
9728If <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>
9729
9730The
9731impact of a plant canopy on a turbulent flow is considered by an
9732additional drag term in the momentum equations and an additional sink
9733term in the prognostic equation for the subgrid-scale TKE. These
9734additional 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 <a href="#pch_index">pch_index</a>. For all heights equal to or larger than zw(k=<span style="font-weight: bold;">pch_index</span>) the leaf area density is 0 (i.e. there is no canopy at these heights!). <br>
9735
9736By default, a horizontally homogeneous plant canopy is prescribed, if&nbsp; <span style="font-weight: bold;">plant_canopy</span> is set <span style="font-style: italic;">.T.</span>. However, the user can define other types of plant canopies (see <a href="#canopy_mode">canopy_mode</a>).<br><br>If <span style="font-weight: bold;">plant_canopy</span> and&nbsp; <span style="font-weight: bold;">passive_scalar</span><span style="font-style: italic;"> </span>are set <span style="font-style: italic;">.T.</span>,
9737the canopy acts as an additional source or sink, respectively, of
9738scalar concentration. The source/sink strength is dependent on the
9739scalar concentration at the leaf surface, which is generally constant
9740with time in PALM and which can be specified by specifying the
9741parameter <a href="#leaf_surface_concentration">leaf_surface_concentration</a>. <br><br>Additional heating of the air by the plant canopy is taken into account, when the default value of the parameter <a href="#cthf">cthf</a> is altered in the parameter file. In that case the value of <a href="#surface_heatflux">surface_heatflux</a>
9742specified in the parameter file is not used in the model. Instead the
9743near-surface heat flux is derived from an expontial function that is
9744dependent on the cumulative leaf area index. <br> 
9745
9746      <br>
9747
9748      <span style="font-weight: bold;">plant_canopy</span> = <span style="font-style: italic;">.T. </span>is only allowed together with a non-zero <a href="#drag_coefficient">drag_coefficient</a>.</td>
9749
9750    </tr>
9751
9752    <tr>
9753
9754
9755
9756
9757
9758
9759 <td style="vertical-align: top;"> 
9760     
9761     
9762     
9763     
9764     
9765     
9766      <p><a name="prandtl_layer"></a><b>prandtl_layer</b></p>
9767
9768
9769
9770
9771
9772
9773
9774      </td>
9775
9776
9777
9778
9779
9780
9781 <td style="vertical-align: top;">L</td>
9782
9783
9784
9785
9786
9787
9788
9789      <td style="vertical-align: top;"><i>.T.</i></td>
9790
9791
9792
9793
9794
9795
9796
9797      <td style="vertical-align: top;"> 
9798     
9799     
9800     
9801     
9802     
9803     
9804      <p>Parameter to
9805switch on a Prandtl layer.&nbsp; </p>
9806
9807
9808
9809
9810
9811
9812 
9813     
9814     
9815     
9816     
9817     
9818     
9819      <p>By default,
9820a Prandtl layer is switched on at the bottom
9821boundary between z = 0 and z = 0.5 * <a href="#dz">dz</a>
9822(the first computational grid point above ground for u, v and the
9823scalar quantities).
9824In this case, at the bottom boundary, free-slip conditions for u and v
9825(see <a href="#bc_uv_b">bc_uv_b</a>)
9826are not allowed. Likewise, laminar
9827simulations with constant eddy diffusivities (<a href="#km_constant">km_constant</a>)
9828are forbidden.&nbsp; </p>
9829
9830
9831
9832
9833
9834
9835 
9836     
9837     
9838     
9839     
9840     
9841     
9842      <p>With Prandtl-layer
9843switched off, the TKE boundary condition <a href="#bc_e_b">bc_e_b</a>
9844= '<i>(u*)**2+neumann'</i> must not be used and is
9845automatically
9846changed to <i>'neumann'</i> if necessary.&nbsp; Also,
9847the pressure
9848boundary condition <a href="#bc_p_b">bc_p_b</a>
9849= <i>'neumann+inhomo'</i>&nbsp; is not allowed. </p>
9850
9851
9852
9853
9854
9855
9856
9857     
9858     
9859     
9860     
9861     
9862     
9863      <p>The roughness length is declared via the parameter <a href="#roughness_length">roughness_length</a>.</p>
9864
9865
9866
9867
9868
9869
9870
9871      </td>
9872
9873
9874
9875
9876
9877
9878 </tr>
9879
9880
9881
9882
9883
9884
9885 <tr>
9886
9887
9888
9889
9890
9891
9892 <td style="vertical-align: top;"> 
9893     
9894     
9895     
9896     
9897     
9898     
9899      <p><a name="precipitation"></a><b>precipitation</b></p>
9900
9901
9902
9903
9904
9905
9906
9907      </td>
9908
9909
9910
9911
9912
9913
9914 <td style="vertical-align: top;">L</td>
9915
9916
9917
9918
9919
9920
9921
9922      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9923
9924
9925
9926
9927
9928
9929 <td style="vertical-align: top;"> 
9930     
9931     
9932     
9933     
9934     
9935     
9936      <p>Parameter to switch
9937on the precipitation scheme.<br>
9938
9939
9940
9941
9942
9943
9944 </p>
9945
9946
9947
9948
9949
9950
9951 
9952     
9953     
9954     
9955     
9956     
9957     
9958      <p>For
9959precipitation processes PALM uses a simplified Kessler
9960scheme. This scheme only considers the
9961so-called autoconversion, that means the generation of rain water by
9962coagulation of cloud drops among themselves. Precipitation begins and
9963is immediately removed from the flow as soon as the liquid water
9964content exceeds the critical value of 0.5 g/kg.</p>
9965
9966
9967
9968
9969
9970
9971     
9972     
9973     
9974     
9975     
9976     
9977      <p>The precipitation rate and amount can be output by assigning the runtime parameter <a href="chapter_4.2.html#data_output">data_output</a> = <span style="font-style: italic;">'prr*'</span> or <span style="font-style: italic;">'pra*'</span>, respectively. The time interval on which the precipitation amount is defined can be controlled via runtime parameter <a href="chapter_4.2.html#precipitation_amount_interval">precipitation_amount_interval</a>.</p>
9978
9979
9980
9981
9982
9983
9984 </td>
9985
9986
9987
9988
9989
9990
9991 </tr>
9992
9993
9994
9995
9996
9997
9998
9999    <tr>
10000
10001
10002
10003
10004
10005
10006      <td style="vertical-align: top;"><a name="pt_reference"></a><span style="font-weight: bold;">pt_reference</span></td>
10007
10008
10009
10010
10011
10012
10013      <td style="vertical-align: top;">R</td>
10014
10015
10016
10017
10018
10019
10020      <td style="vertical-align: top;"><span style="font-style: italic;">use horizontal average as
10021refrence</span></td>
10022
10023
10024
10025
10026
10027
10028      <td style="vertical-align: top;">Reference
10029temperature to be used in all buoyancy terms (in K).<br>
10030
10031
10032
10033
10034
10035
10036      <br>
10037
10038
10039
10040
10041
10042
10043By
10044default, the instantaneous horizontal average over the total model
10045domain is used.<br>
10046
10047
10048
10049
10050
10051
10052      <br>
10053
10054
10055
10056
10057
10058
10059      <span style="font-weight: bold;">Attention:</span><br>
10060
10061
10062
10063
10064
10065
10066In case of ocean runs (see <a href="chapter_4.1.html#ocean">ocean</a>), always a reference temperature is used in the buoyancy terms with a default value of <span style="font-weight: bold;">pt_reference</span> = <a href="#pt_surface">pt_surface</a>.</td>
10067
10068
10069
10070
10071
10072
10073    </tr>
10074
10075
10076
10077
10078
10079
10080    <tr>
10081
10082
10083
10084
10085
10086
10087 <td style="vertical-align: top;"> 
10088     
10089     
10090     
10091     
10092     
10093     
10094      <p><a name="pt_surface"></a><b>pt_surface</b></p>
10095
10096
10097
10098
10099
10100
10101
10102      </td>
10103
10104
10105
10106
10107
10108
10109 <td style="vertical-align: top;">R</td>
10110
10111
10112
10113
10114
10115
10116
10117      <td style="vertical-align: top;"><i>300.0</i></td>
10118
10119
10120
10121
10122
10123
10124
10125      <td style="vertical-align: top;"> 
10126     
10127     
10128     
10129     
10130     
10131     
10132      <p>Surface
10133potential temperature (in K).&nbsp; </p>
10134
10135
10136
10137
10138
10139
10140 
10141     
10142     
10143     
10144     
10145     
10146     
10147      <p>This
10148parameter assigns the value of the potential temperature
10149      <span style="font-weight: bold;">pt</span> at the surface (k=0)<b>.</b> Starting from this value,
10150the
10151initial vertical temperature profile is constructed with <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10152and <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level
10153      </a>.
10154This profile is also used for the 1d-model as a stationary profile.</p>
10155
10156
10157
10158
10159
10160
10161     
10162     
10163     
10164     
10165     
10166     
10167      <p><span style="font-weight: bold;">Attention:</span><br>
10168
10169
10170
10171
10172
10173
10174In case of ocean runs (see <a href="#ocean">ocean</a>),
10175this parameter gives the temperature value at the sea surface, which is
10176at k=nzt. The profile is then constructed from the surface down to the
10177bottom of the model.</p>
10178
10179
10180
10181
10182
10183
10184
10185      </td>
10186
10187
10188
10189
10190
10191
10192 </tr>
10193
10194
10195
10196
10197
10198
10199 <tr>
10200
10201
10202
10203
10204
10205
10206 <td style="vertical-align: top;"> 
10207     
10208     
10209     
10210     
10211     
10212     
10213      <p><a name="pt_surface_initial_change"></a><b>pt_surface_initial</b>
10214      <br>
10215
10216
10217
10218
10219
10220
10221 <b>_change</b></p>
10222
10223
10224
10225
10226
10227
10228 </td>
10229
10230
10231
10232
10233
10234
10235 <td style="vertical-align: top;">R</td>
10236
10237
10238
10239
10240
10241
10242 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
10243
10244
10245
10246
10247
10248
10249 </td>
10250
10251
10252
10253
10254
10255
10256
10257      <td style="vertical-align: top;"> 
10258     
10259     
10260     
10261     
10262     
10263     
10264      <p>Change in
10265surface temperature to be made at the beginning of
10266the 3d run
10267(in K).&nbsp; </p>
10268
10269
10270
10271
10272
10273
10274 
10275     
10276     
10277     
10278     
10279     
10280     
10281      <p>If <b>pt_surface_initial_change</b>
10282is set to a non-zero
10283value, the near surface sensible heat flux is not allowed to be given
10284simultaneously (see <a href="#surface_heatflux">surface_heatflux</a>).</p>
10285
10286
10287
10288
10289
10290
10291
10292      </td>
10293
10294
10295
10296
10297
10298
10299 </tr>
10300
10301
10302
10303
10304
10305
10306 <tr>
10307
10308
10309
10310
10311
10312
10313 <td style="vertical-align: top;"> 
10314     
10315     
10316     
10317     
10318     
10319     
10320      <p><a name="pt_vertical_gradient"></a><b>pt_vertical_gradient</b></p>
10321
10322
10323
10324
10325
10326
10327
10328      </td>
10329
10330
10331
10332
10333
10334
10335 <td style="vertical-align: top;">R (10)</td>
10336
10337
10338
10339
10340
10341
10342
10343      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
10344
10345
10346
10347
10348
10349
10350
10351      <td style="vertical-align: top;"> 
10352     
10353     
10354     
10355     
10356     
10357     
10358      <p>Temperature
10359gradient(s) of the initial temperature profile (in
10360K
10361/ 100 m).&nbsp; </p>
10362
10363
10364
10365
10366
10367
10368 
10369     
10370     
10371     
10372     
10373     
10374     
10375      <p>This temperature gradient
10376holds starting from the height&nbsp;
10377level defined by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>
10378(precisely: for all uv levels k where zu(k) &gt;
10379pt_vertical_gradient_level,
10380pt_init(k) is set: pt_init(k) = pt_init(k-1) + dzu(k) * <b>pt_vertical_gradient</b>)
10381up to the top boundary or up to the next height level defined
10382by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>.
10383A total of 10 different gradients for 11 height intervals (10 intervals
10384if <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>(1)
10385= <i>0.0</i>) can be assigned. The surface temperature is
10386assigned via <a href="#pt_surface">pt_surface</a>.&nbsp;
10387      </p>
10388
10389
10390
10391
10392
10393
10394 
10395     
10396     
10397     
10398     
10399     
10400     
10401      <p>Example:&nbsp; </p>
10402
10403
10404
10405
10406
10407
10408 
10409     
10410     
10411     
10412     
10413     
10414     
10415      <ul>
10416
10417
10418
10419
10420
10421
10422 
10423       
10424       
10425       
10426       
10427       
10428       
10429        <p><b>pt_vertical_gradient</b>
10430= <i>1.0</i>, <i>0.5</i>,&nbsp; <br>
10431
10432
10433
10434
10435
10436
10437
10438        <b>pt_vertical_gradient_level</b> = <i>500.0</i>,
10439        <i>1000.0</i>,</p>
10440
10441
10442
10443
10444
10445
10446 
10447     
10448     
10449     
10450     
10451     
10452     
10453      </ul>
10454
10455
10456
10457
10458
10459
10460 
10461     
10462     
10463     
10464     
10465     
10466     
10467      <p>That
10468defines the temperature profile to be neutrally
10469stratified
10470up to z = 500.0 m with a temperature given by <a href="#pt_surface">pt_surface</a>.
10471For 500.0 m &lt; z &lt;= 1000.0 m the temperature gradient is
104721.0 K /
10473100 m and for z &gt; 1000.0 m up to the top boundary it is
104740.5 K / 100 m (it is assumed that the assigned height levels correspond
10475with uv levels).</p>
10476
10477
10478
10479
10480
10481
10482     
10483     
10484     
10485     
10486     
10487     
10488      <p><span style="font-weight: bold;">Attention:</span><br>
10489
10490
10491
10492
10493
10494
10495In case of ocean runs (see <a href="chapter_4.1.html#ocean">ocean</a>),
10496the profile is constructed like described above, but starting from the
10497sea surface (k=nzt) down to the bottom boundary of the model. Height
10498levels have then to be given as negative values, e.g. <span style="font-weight: bold;">pt_vertical_gradient_level</span> = <span style="font-style: italic;">-500.0</span>, <span style="font-style: italic;">-1000.0</span>.</p>
10499
10500
10501
10502
10503
10504
10505 </td>
10506
10507
10508
10509
10510
10511
10512 </tr>
10513
10514
10515
10516
10517
10518
10519 <tr>
10520
10521
10522
10523
10524
10525
10526 <td style="vertical-align: top;"> 
10527     
10528     
10529     
10530     
10531     
10532     
10533      <p><a name="pt_vertical_gradient_level"></a><b>pt_vertical_gradient</b>
10534      <br>
10535
10536
10537
10538
10539
10540
10541 <b>_level</b></p>
10542
10543
10544
10545
10546
10547
10548 </td>
10549
10550
10551
10552
10553
10554
10555 <td style="vertical-align: top;">R (10)</td>
10556
10557
10558
10559
10560
10561
10562 <td style="vertical-align: top;"> 
10563     
10564     
10565     
10566     
10567     
10568     
10569      <p><i>10 *</i>&nbsp;
10570      <span style="font-style: italic;">0.0</span><br>
10571
10572
10573
10574
10575
10576
10577
10578      </p>
10579
10580
10581
10582
10583
10584
10585 </td>
10586
10587
10588
10589
10590
10591
10592 <td style="vertical-align: top;">
10593     
10594     
10595     
10596     
10597     
10598     
10599      <p>Height level from which on the temperature gradient defined by
10600      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10601is effective (in m).&nbsp; </p>
10602
10603
10604
10605
10606
10607
10608 
10609     
10610     
10611     
10612     
10613     
10614     
10615      <p>The height levels have to be assigned in ascending order. The
10616default values result in a neutral stratification regardless of the
10617values of <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10618(unless the top boundary of the model is higher than 100000.0 m).
10619For the piecewise construction of temperature profiles see <a href="#pt_vertical_gradient">pt_vertical_gradient</a>.</p>
10620
10621
10622
10623
10624
10625
10626      <span style="font-weight: bold;">Attention:</span><br>
10627
10628
10629
10630
10631
10632
10633In case of ocean runs&nbsp;(see <a href="chapter_4.1.html#ocean">ocean</a>), the (negative) height levels have to be assigned in descending order.
10634      </td>
10635
10636
10637
10638
10639
10640
10641 </tr>
10642
10643
10644
10645
10646
10647
10648 <tr>
10649
10650
10651
10652
10653
10654
10655 <td style="vertical-align: top;"> 
10656     
10657     
10658     
10659     
10660     
10661     
10662      <p><a name="q_surface"></a><b>q_surface</b></p>
10663
10664
10665
10666
10667
10668
10669
10670      </td>
10671
10672
10673
10674
10675
10676
10677 <td style="vertical-align: top;">R</td>
10678
10679
10680
10681
10682
10683
10684
10685      <td style="vertical-align: top;"><i>0.0</i></td>
10686
10687
10688
10689
10690
10691
10692
10693      <td style="vertical-align: top;"> 
10694     
10695     
10696     
10697     
10698     
10699     
10700      <p>Surface
10701specific humidity / total water content (kg/kg).&nbsp; </p>
10702
10703
10704
10705
10706
10707
10708 
10709     
10710     
10711     
10712     
10713     
10714     
10715      <p>This
10716parameter assigns the value of the specific humidity q at
10717the surface (k=0).&nbsp; Starting from this value, the initial
10718humidity
10719profile is constructed with&nbsp; <a href="#q_vertical_gradient">q_vertical_gradient</a>
10720and <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
10721This profile is also used for the 1d-model as a stationary profile.</p>
10722
10723
10724
10725
10726
10727
10728
10729      </td>
10730
10731
10732
10733
10734
10735
10736 </tr>
10737
10738
10739
10740
10741
10742
10743 <tr>
10744
10745
10746
10747
10748
10749
10750 <td style="vertical-align: top;"> 
10751     
10752     
10753     
10754     
10755     
10756     
10757      <p><a name="q_surface_initial_change"></a><b>q_surface_initial</b>
10758      <br>
10759
10760
10761
10762
10763
10764
10765 <b>_change</b></p>
10766
10767
10768
10769
10770
10771
10772 </td>
10773
10774
10775
10776
10777
10778
10779 <td style="vertical-align: top;">R<br>
10780
10781
10782
10783
10784
10785
10786