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29  <title>PALM chapter 4.1</title></head>
30<body>
31
32
33
34
35
36
37<h3><a name="chapter4.1"></a>4.1
38Initialization parameters</h3>
39
40
41
42
43
44
45
46<br>
47
48
49
50
51
52
53<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
54
55
56
57
58
59
60 <tbody>
61
62
63
64
65
66
67
68    <tr>
69
70
71
72
73
74
75 <td style="vertical-align: top;"><font size="4"><b>Parameter name</b></font></td>
76
77
78
79
80
81
82
83      <td style="vertical-align: top;"><font size="4"><b>Type</b></font></td>
84
85
86
87
88
89
90
91      <td style="vertical-align: top;"> 
92     
93     
94     
95     
96     
97     
98      <p><b><font size="4">Default</font></b> <br>
99
100
101
102
103
104
105 <b><font size="4">value</font></b></p>
106
107
108
109
110
111
112 </td>
113
114
115
116
117
118
119
120      <td style="vertical-align: top;"><font size="4"><b>Explanation</b></font></td>
121
122
123
124
125
126
127
128    </tr>
129
130
131
132
133
134
135 <tr>
136
137
138
139
140
141
142 <td style="vertical-align: top;">
143     
144     
145     
146     
147     
148     
149      <p><a name="adjust_mixing_length"></a><b>adjust_mixing_length</b></p>
150
151
152
153
154
155
156
157      </td>
158
159
160
161
162
163
164 <td style="vertical-align: top;">L</td>
165
166
167
168
169
170
171
172      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
173
174
175
176
177
178
179 <td style="vertical-align: top;"> 
180     
181     
182     
183     
184     
185     
186      <p style="font-style: normal;">Near-surface adjustment of the
187mixing length to the Prandtl-layer law.&nbsp; </p>
188
189
190
191
192
193
194 
195     
196     
197     
198     
199     
200     
201      <p>Usually
202the mixing length in LES models l<sub>LES</sub>
203depends (as in PALM) on the grid size and is possibly restricted
204further in case of stable stratification and near the lower wall (see
205parameter <a href="#wall_adjustment">wall_adjustment</a>).
206With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span>
207the Prandtl' mixing length l<sub>PR</sub> = kappa * z/phi
208is calculated
209and the mixing length actually used in the model is set l = MIN (l<sub>LES</sub>,
210l<sub>PR</sub>). This usually gives a decrease of the
211mixing length at
212the bottom boundary and considers the fact that eddy sizes
213decrease in the vicinity of the wall.&nbsp; </p>
214
215
216
217
218
219
220 
221     
222     
223     
224     
225     
226     
227      <p style="font-style: normal;"><b>Warning:</b> So
228far, there is
229no good experience with <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> !&nbsp; </p>
230
231
232
233
234
235
236
237     
238     
239     
240     
241     
242     
243      <p>With <b>adjust_mixing_length</b> = <span style="font-style: italic;">.T.</span> and the
244Prandtl-layer being
245switched on (see <a href="#prandtl_layer">prandtl_layer</a>)
246      <span style="font-style: italic;">'(u*)** 2+neumann'</span>
247should always be set as the lower boundary condition for the TKE (see <a href="#bc_e_b">bc_e_b</a>),
248otherwise the near-surface value of the TKE is not in agreement with
249the Prandtl-layer law (Prandtl-layer law and Prandtl-Kolmogorov-Ansatz
250should provide the same value for K<sub>m</sub>). A warning
251is given,
252if this is not the case.</p>
253
254
255
256
257
258
259 </td>
260
261
262
263
264
265
266 </tr>
267
268
269
270
271
272
273 <tr>
274
275
276
277
278
279
280
281      <td style="vertical-align: top;"> 
282     
283     
284     
285     
286     
287     
288      <p><a name="alpha_surface"></a><b>alpha_surface</b></p>
289
290
291
292
293
294
295
296      </td>
297
298
299
300
301
302
303 <td style="vertical-align: top;">R<br>
304
305
306
307
308
309
310 </td>
311
312
313
314
315
316
317
318      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
319
320
321
322
323
324
325 </td>
326
327
328
329
330
331
332
333      <td style="vertical-align: top;"> 
334     
335     
336     
337     
338     
339     
340      <p style="font-style: normal;">Inclination of the model domain
341with respect to the horizontal (in degrees).&nbsp; </p>
342
343
344
345
346
347
348 
349     
350     
351     
352     
353     
354     
355      <p style="font-style: normal;">By means of <b>alpha_surface</b>
356the model domain can be inclined in x-direction with respect to the
357horizontal. In this way flows over inclined surfaces (e.g. drainage
358flows, gravity flows) can be simulated. In case of <b>alpha_surface
359      </b>/= <span style="font-style: italic;">0</span>
360the buoyancy term
361appears both in
362the equation of motion of the u-component and of the w-component.<br>
363
364
365
366
367
368
369
370      </p>
371
372
373
374
375
376
377 
378     
379     
380     
381     
382     
383     
384      <p style="font-style: normal;">An inclination
385is only possible in
386case of cyclic horizontal boundary conditions along x AND y (see <a href="#bc_lr">bc_lr</a>
387and <a href="#bc_ns">bc_ns</a>) and <a href="#topography">topography</a> = <span style="font-style: italic;">'flat'</span>. </p>
388
389
390
391
392
393
394
395     
396     
397     
398     
399     
400     
401      <p>Runs with inclined surface still require additional
402user-defined code as well as modifications to the default code. Please
403ask the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/PALM_group.html#0">PALM
404developer&nbsp; group</a>.</p>
405
406
407
408
409
410
411 </td>
412
413
414
415
416
417
418 </tr>
419
420
421
422
423
424
425
426    <tr>
427
428
429
430
431
432
433 <td style="vertical-align: top;"> 
434     
435     
436     
437     
438     
439     
440      <p><a name="bc_e_b"></a><b>bc_e_b</b></p>
441
442
443
444
445
446
447 </td>
448
449
450
451
452
453
454
455      <td style="vertical-align: top;">C * 20</td>
456
457
458
459
460
461
462 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
463
464
465
466
467
468
469
470      <td style="vertical-align: top;"> 
471     
472     
473     
474     
475     
476     
477      <p style="font-style: normal;">Bottom boundary condition of the
478TKE.&nbsp; </p>
479
480
481
482
483
484
485 
486     
487     
488     
489     
490     
491     
492      <p><b>bc_e_b</b> may be
493set to&nbsp;<span style="font-style: italic;">'neumann'</span>
494or <span style="font-style: italic;">'(u*) ** 2+neumann'</span>.
495      <b>bc_e_b</b>
496= <span style="font-style: italic;">'neumann'</span>
497yields to
498e(k=0)=e(k=1) (Neumann boundary condition), where e(k=1) is calculated
499via the prognostic TKE equation. Choice of <span style="font-style: italic;">'(u*)**2+neumann'</span>
500also yields to
501e(k=0)=e(k=1), but the TKE at the Prandtl-layer top (k=1) is calculated
502diagnostically by e(k=1)=(us/0.1)**2. However, this is only allowed if
503a Prandtl-layer is used (<a href="#prandtl_layer">prandtl_layer</a>).
504If this is not the case, a warning is given and <b>bc_e_b</b>
505is reset
506to <span style="font-style: italic;">'neumann'</span>.&nbsp;
507      </p>
508
509
510
511
512
513
514 
515     
516     
517     
518     
519     
520     
521      <p style="font-style: normal;">At the top
522boundary a Neumann
523boundary condition is generally used: (e(nz+1) = e(nz)).</p>
524
525
526
527
528
529
530 </td>
531
532
533
534
535
536
537
538    </tr>
539
540
541
542
543
544
545 <tr>
546
547
548
549
550
551
552 <td style="vertical-align: top;">
553     
554     
555     
556     
557     
558     
559      <p><a name="bc_lr"></a><b>bc_lr</b></p>
560
561
562
563
564
565
566
567      </td>
568
569
570
571
572
573
574 <td style="vertical-align: top;">C * 20</td>
575
576
577
578
579
580
581
582      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
583
584
585
586
587
588
589
590      <td style="vertical-align: top;">Boundary
591condition along x (for all quantities).<br>
592
593
594
595
596
597
598 <br>
599
600
601
602
603
604
605
606By default, a cyclic boundary condition is used along x.<br>
607
608
609
610
611
612
613 <br>
614
615
616
617
618
619
620
621      <span style="font-weight: bold;">bc_lr</span> may
622also be
623assigned the values <span style="font-style: italic;">'dirichlet/radiation'</span>
624(inflow from left, outflow to the right) or <span style="font-style: italic;">'radiation/dirichlet'</span>
625(inflow from
626right, outflow to the left). This requires the multi-grid method to be
627used for solving the Poisson equation for perturbation pressure (see <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">psolver</a>)
628and it also requires cyclic boundary conditions along y (see&nbsp;<a href="#bc_ns">bc_ns</a>).<br>
629
630
631
632
633
634
635 <br>
636
637
638
639
640
641
642
643In case of these non-cyclic lateral boundaries, a Dirichlet condition
644is used at the inflow for all quantities (initial vertical profiles -
645see <a href="#initializing_actions">initializing_actions</a>
646- are fixed during the run) except u, to which a Neumann (zero
647gradient) condition is applied. At the outflow, a radiation condition is used for all velocity components, while a Neumann (zero
648gradient) condition is used for the scalars. For perturbation
649pressure Neumann (zero gradient) conditions are assumed both at the
650inflow and at the outflow.<br>
651
652
653
654
655
656
657 <br>
658
659
660
661
662
663
664
665When using non-cyclic lateral boundaries, a filter is applied to the
666velocity field in the vicinity of the outflow in order to suppress any
667reflections of outgoing disturbances (see <a href="#km_damp_max">km_damp_max</a>
668and <a href="#outflow_damping_width">outflow_damping_width</a>).<br>
669
670
671
672
673
674
675
676      <br>
677
678
679
680
681
682
683
684In order to maintain a turbulent state of the flow, it may be
685neccessary to continuously impose perturbations on the horizontal
686velocity field in the vicinity of the inflow throughout the whole run.
687This can be switched on using <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#create_disturbances">create_disturbances</a>.
688The horizontal range to which these perturbations are applied is
689controlled by the parameters <a href="#inflow_disturbance_begin">inflow_disturbance_begin</a>
690and <a href="#inflow_disturbance_end">inflow_disturbance_end</a>.
691The vertical range and the perturbation amplitude are given by <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_level_b</a>,
692      <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_level_t</a>,
693and <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#psolver">disturbance_amplitude</a>.
694The time interval at which perturbations are to be imposed is set by <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#dt_disturb">dt_disturb</a>.<br>
695
696
697
698
699
700
701
702      <br>
703
704
705
706
707
708
709
710In case of non-cyclic horizontal boundaries <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM_group/doc/app/chapter_4.2.html#call_psolver_at_all_substeps">call_psolver
711at_all_substeps</a> = .T. should be used.<br>
712
713
714
715
716
717
718 <br>
719
720
721
722
723
724
725 <span style="font-weight: bold;">Note:</span><br>
726
727
728
729
730
731
732
733Using non-cyclic lateral boundaries requires very sensitive adjustments
734of the inflow (vertical profiles) and the bottom boundary conditions,
735e.g. a surface heating should not be applied near the inflow boundary
736because this may significantly disturb the inflow. Please check the
737model results very carefully.</td>
738
739
740
741
742
743
744 </tr>
745
746
747
748
749
750
751 <tr>
752
753
754
755
756
757
758 <td style="vertical-align: top;"> 
759     
760     
761     
762     
763     
764     
765      <p><a name="bc_ns"></a><b>bc_ns</b></p>
766
767
768
769
770
771
772
773      </td>
774
775
776
777
778
779
780 <td style="vertical-align: top;">C * 20</td>
781
782
783
784
785
786
787
788      <td style="vertical-align: top;"><span style="font-style: italic;">'cyclic'</span></td>
789
790
791
792
793
794
795
796      <td style="vertical-align: top;">Boundary
797condition along y (for all quantities).<br>
798
799
800
801
802
803
804 <br>
805
806
807
808
809
810
811
812By default, a cyclic boundary condition is used along y.<br>
813
814
815
816
817
818
819 <br>
820
821
822
823
824
825
826
827      <span style="font-weight: bold;">bc_ns</span> may
828also be
829assigned the values <span style="font-style: italic;">'dirichlet/radiation'</span>
830(inflow from rear ("north"), outflow to the front ("south")) or <span style="font-style: italic;">'radiation/dirichlet'</span>
831(inflow from front ("south"), outflow to the rear ("north")). This
832requires the multi-grid
833method to be used for solving the Poisson equation for perturbation
834pressure (see <a href="chapter_4.2.html#psolver">psolver</a>)
835and it also requires cyclic boundary conditions along x (see<br>
836
837
838
839
840
841
842 <a href="#bc_lr">bc_lr</a>).<br>
843
844
845
846
847
848
849 <br>
850
851
852
853
854
855
856
857In case of these non-cyclic lateral boundaries, a Dirichlet condition
858is used at the inflow for all quantities (initial vertical profiles -
859see <a href="chapter_4.1.html#initializing_actions">initializing_actions</a>
860- are fixed during the run) except u, to which a Neumann (zero
861gradient) condition is applied. At the outflow, a radiation condition is used for all velocity components, while a Neumann (zero
862gradient) condition is used for the scalars. For perturbation
863pressure Neumann (zero gradient) conditions are assumed both at the
864inflow and at the outflow.<br>
865
866
867
868
869
870
871 <br>
872
873
874
875
876
877
878
879For further details regarding non-cyclic lateral boundary conditions
880see <a href="#bc_lr">bc_lr</a>.</td>
881
882
883
884
885
886
887 </tr>
888
889
890
891
892
893
894
895    <tr>
896
897
898
899
900
901
902 <td style="vertical-align: top;"> 
903     
904     
905     
906     
907     
908     
909      <p><a name="bc_p_b"></a><b>bc_p_b</b></p>
910
911
912
913
914
915
916 </td>
917
918
919
920
921
922
923
924      <td style="vertical-align: top;">C * 20</td>
925
926
927
928
929
930
931 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
932
933
934
935
936
937
938
939      <td style="vertical-align: top;"> 
940     
941     
942     
943     
944     
945     
946      <p style="font-style: normal;">Bottom boundary condition of the
947perturbation pressure.&nbsp; </p>
948
949
950
951
952
953
954 
955     
956     
957     
958     
959     
960     
961      <p>Allowed values
962are <span style="font-style: italic;">'dirichlet'</span>,
963      <span style="font-style: italic;">'neumann'</span>
964and <span style="font-style: italic;">'neumann+inhomo'</span>.&nbsp;
965      <span style="font-style: italic;">'dirichlet'</span>
966sets
967p(k=0)=0.0,&nbsp; <span style="font-style: italic;">'neumann'</span>
968sets p(k=0)=p(k=1). <span style="font-style: italic;">'neumann+inhomo'</span>
969corresponds to an extended Neumann boundary condition where heat flux
970or temperature inhomogeneities near the
971surface (pt(k=1))&nbsp; are additionally regarded (see Shen and
972LeClerc
973(1995, Q.J.R. Meteorol. Soc.,
9741209)). This condition is only permitted with the Prandtl-layer
975switched on (<a href="#prandtl_layer">prandtl_layer</a>),
976otherwise the run is terminated.&nbsp; </p>
977
978
979
980
981
982
983 
984     
985     
986     
987     
988     
989     
990      <p>Since
991at the bottom boundary of the model the vertical
992velocity
993disappears (w(k=0) = 0.0), the consistent Neumann condition (<span style="font-style: italic;">'neumann'</span> or <span style="font-style: italic;">'neumann+inhomo'</span>)
994dp/dz = 0 should
995be used, which leaves the vertical component w unchanged when the
996pressure solver is applied. Simultaneous use of the Neumann boundary
997conditions both at the bottom and at the top boundary (<a href="#bc_p_t">bc_p_t</a>)
998usually yields no consistent solution for the perturbation pressure and
999should be avoided.</p>
1000
1001
1002
1003
1004
1005
1006 </td>
1007
1008
1009
1010
1011
1012
1013 </tr>
1014
1015
1016
1017
1018
1019
1020 <tr>
1021
1022
1023
1024
1025
1026
1027 <td style="vertical-align: top;"> 
1028     
1029     
1030     
1031     
1032     
1033     
1034      <p><a name="bc_p_t"></a><b>bc_p_t</b></p>
1035
1036
1037
1038
1039
1040
1041
1042      </td>
1043
1044
1045
1046
1047
1048
1049 <td style="vertical-align: top;">C * 20</td>
1050
1051
1052
1053
1054
1055
1056
1057      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1058
1059
1060
1061
1062
1063
1064
1065      <td style="vertical-align: top;"> 
1066     
1067     
1068     
1069     
1070     
1071     
1072      <p style="font-style: normal;">Top boundary condition of the
1073perturbation pressure.&nbsp; </p>
1074
1075
1076
1077
1078
1079
1080 
1081     
1082     
1083     
1084     
1085     
1086     
1087      <p style="font-style: normal;">Allowed values are <span style="font-style: italic;">'dirichlet'</span>
1088(p(k=nz+1)= 0.0) or <span style="font-style: italic;">'neumann'</span>
1089(p(k=nz+1)=p(k=nz)).&nbsp; </p>
1090
1091
1092
1093
1094
1095
1096 
1097     
1098     
1099     
1100     
1101     
1102     
1103      <p>Simultaneous use
1104of Neumann boundary conditions both at the
1105top and bottom boundary (<a href="#bc_p_b">bc_p_b</a>)
1106usually yields no consistent solution for the perturbation pressure and
1107should be avoided. Since at the bottom boundary the Neumann
1108condition&nbsp; is a good choice (see <a href="#bc_p_b">bc_p_b</a>),
1109a Dirichlet condition should be set at the top boundary.</p>
1110
1111
1112
1113
1114
1115
1116 </td>
1117
1118
1119
1120
1121
1122
1123
1124    </tr>
1125
1126
1127
1128
1129
1130
1131 <tr>
1132
1133
1134
1135
1136
1137
1138 <td style="vertical-align: top;">
1139     
1140     
1141     
1142     
1143     
1144     
1145      <p><a name="bc_pt_b"></a><b>bc_pt_b</b></p>
1146
1147
1148
1149
1150
1151
1152
1153      </td>
1154
1155
1156
1157
1158
1159
1160 <td style="vertical-align: top;">C*20</td>
1161
1162
1163
1164
1165
1166
1167
1168      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1169
1170
1171
1172
1173
1174
1175
1176      <td style="vertical-align: top;"> 
1177     
1178     
1179     
1180     
1181     
1182     
1183      <p style="font-style: normal;">Bottom boundary condition of the
1184potential temperature.&nbsp; </p>
1185
1186
1187
1188
1189
1190
1191 
1192     
1193     
1194     
1195     
1196     
1197     
1198      <p>Allowed values
1199are <span style="font-style: italic;">'dirichlet'</span>
1200(pt(k=0) = const. = <a href="#pt_surface">pt_surface</a>
1201+ <a href="#pt_surface_initial_change">pt_surface_initial_change</a>;
1202the user may change this value during the run using user-defined code)
1203and <span style="font-style: italic;">'neumann'</span>
1204(pt(k=0)=pt(k=1)).&nbsp; <br>
1205
1206
1207
1208
1209
1210
1211
1212When a constant surface sensible heat flux is used (<a href="#surface_heatflux">surface_heatflux</a>), <b>bc_pt_b</b>
1213= <span style="font-style: italic;">'neumann'</span>
1214must be used, because otherwise the resolved scale may contribute to
1215the surface flux so that a constant value cannot be guaranteed.</p>
1216
1217
1218
1219
1220
1221
1222     
1223     
1224     
1225     
1226     
1227     
1228      <p>In the <a href="chapter_3.8.html">coupled</a> atmosphere executable,&nbsp;<a href="chapter_4.2.html#bc_pt_b">bc_pt_b</a> is internally set and does not need to be prescribed.</p>
1229
1230
1231
1232
1233
1234
1235
1236      </td>
1237
1238
1239
1240
1241
1242
1243 </tr>
1244
1245
1246
1247
1248
1249
1250 <tr>
1251
1252
1253
1254
1255
1256
1257 <td style="vertical-align: top;"> 
1258     
1259     
1260     
1261     
1262     
1263     
1264      <p><a name="pc_pt_t"></a><b>bc_pt_t</b></p>
1265
1266
1267
1268
1269
1270
1271
1272      </td>
1273
1274
1275
1276
1277
1278
1279 <td style="vertical-align: top;">C * 20</td>
1280
1281
1282
1283
1284
1285
1286
1287      <td style="vertical-align: top;"><span style="font-style: italic;">'initial_ gradient'</span></td>
1288
1289
1290
1291
1292
1293
1294
1295      <td style="vertical-align: top;"> 
1296     
1297     
1298     
1299     
1300     
1301     
1302      <p style="font-style: normal;">Top boundary condition of the
1303potential temperature.&nbsp; </p>
1304
1305
1306
1307
1308
1309
1310 
1311     
1312     
1313     
1314     
1315     
1316     
1317      <p>Allowed are the
1318values <span style="font-style: italic;">'dirichlet' </span>(pt(k=nz+1)
1319does not change during the run), <span style="font-style: italic;">'neumann'</span>
1320(pt(k=nz+1)=pt(k=nz)), and <span style="font-style: italic;">'initial_gradient'</span>.
1321With the 'initial_gradient'-condition the value of the temperature
1322gradient at the top is
1323calculated from the initial
1324temperature profile (see <a href="#pt_surface">pt_surface</a>,
1325      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>)
1326by bc_pt_t_val = (pt_init(k=nz+1) -
1327pt_init(k=nz)) / dzu(nz+1).<br>
1328
1329
1330
1331
1332
1333
1334
1335Using this value (assumed constant during the
1336run) the temperature boundary values are calculated as&nbsp; </p>
1337
1338
1339
1340
1341
1342
1343
1344     
1345     
1346     
1347     
1348     
1349     
1350      <ul>
1351
1352
1353
1354
1355
1356
1357 
1358       
1359       
1360       
1361       
1362       
1363       
1364        <p style="font-style: normal;">pt(k=nz+1) =
1365pt(k=nz) +
1366bc_pt_t_val * dzu(nz+1)</p>
1367
1368
1369
1370
1371
1372
1373 
1374     
1375     
1376     
1377     
1378     
1379     
1380      </ul>
1381
1382
1383
1384
1385
1386
1387 
1388     
1389     
1390     
1391     
1392     
1393     
1394      <p style="font-style: normal;">(up to k=nz the prognostic
1395equation for the temperature is solved).<br>
1396
1397
1398
1399
1400
1401
1402
1403When a constant sensible heat flux is used at the top boundary (<a href="chapter_4.1.html#top_heatflux">top_heatflux</a>),
1404      <b>bc_pt_t</b> = <span style="font-style: italic;">'neumann'</span>
1405must be used, because otherwise the resolved scale may contribute to
1406the top flux so that a constant value cannot be guaranteed.</p>
1407
1408
1409
1410
1411
1412
1413 </td>
1414
1415
1416
1417
1418
1419
1420
1421    </tr>
1422
1423
1424
1425
1426
1427
1428 <tr>
1429
1430
1431
1432
1433
1434
1435 <td style="vertical-align: top;">
1436     
1437     
1438     
1439     
1440     
1441     
1442      <p><a name="bc_q_b"></a><b>bc_q_b</b></p>
1443
1444
1445
1446
1447
1448
1449
1450      </td>
1451
1452
1453
1454
1455
1456
1457 <td style="vertical-align: top;">C * 20</td>
1458
1459
1460
1461
1462
1463
1464
1465      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1466
1467
1468
1469
1470
1471
1472
1473      <td style="vertical-align: top;"> 
1474     
1475     
1476     
1477     
1478     
1479     
1480      <p style="font-style: normal;">Bottom boundary condition of the
1481specific humidity / total water content.&nbsp; </p>
1482
1483
1484
1485
1486
1487
1488 
1489     
1490     
1491     
1492     
1493     
1494     
1495      <p>Allowed
1496values are <span style="font-style: italic;">'dirichlet'</span>
1497(q(k=0) = const. = <a href="#q_surface">q_surface</a>
1498+ <a href="#q_surface_initial_change">q_surface_initial_change</a>;
1499the user may change this value during the run using user-defined code)
1500and <span style="font-style: italic;">'neumann'</span>
1501(q(k=0)=q(k=1)).&nbsp; <br>
1502
1503
1504
1505
1506
1507
1508
1509When a constant surface latent heat flux is used (<a href="#surface_waterflux">surface_waterflux</a>), <b>bc_q_b</b>
1510= <span style="font-style: italic;">'neumann'</span>
1511must be used, because otherwise the resolved scale may contribute to
1512the surface flux so that a constant value cannot be guaranteed.</p>
1513
1514
1515
1516
1517
1518
1519
1520      </td>
1521
1522
1523
1524
1525
1526
1527 </tr>
1528
1529
1530
1531
1532
1533
1534 <tr>
1535
1536
1537
1538
1539
1540
1541 <td style="vertical-align: top;"> 
1542     
1543     
1544     
1545     
1546     
1547     
1548      <p><a name="bc_q_t"></a><b>bc_q_t</b></p>
1549
1550
1551
1552
1553
1554
1555
1556      </td>
1557
1558
1559
1560
1561
1562
1563 <td style="vertical-align: top;"><span style="font-style: italic;">C
1564* 20</span></td>
1565
1566
1567
1568
1569
1570
1571 <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1572
1573
1574
1575
1576
1577
1578
1579      <td style="vertical-align: top;"> 
1580     
1581     
1582     
1583     
1584     
1585     
1586      <p style="font-style: normal;">Top boundary condition of the
1587specific humidity / total water content.&nbsp; </p>
1588
1589
1590
1591
1592
1593
1594 
1595     
1596     
1597     
1598     
1599     
1600     
1601      <p>Allowed
1602are the values <span style="font-style: italic;">'dirichlet'</span>
1603(q(k=nz) and q(k=nz+1) do
1604not change during the run) and <span style="font-style: italic;">'neumann'</span>.
1605With the Neumann boundary
1606condition the value of the humidity gradient at the top is calculated
1607from the
1608initial humidity profile (see <a href="#q_surface">q_surface</a>,
1609      <a href="#q_vertical_gradient">q_vertical_gradient</a>)
1610by: bc_q_t_val = ( q_init(k=nz) - q_init(k=nz-1)) / dzu(nz).<br>
1611
1612
1613
1614
1615
1616
1617
1618Using this value (assumed constant during the run) the humidity
1619boundary values
1620are calculated as&nbsp; </p>
1621
1622
1623
1624
1625
1626
1627 
1628     
1629     
1630     
1631     
1632     
1633     
1634      <ul>
1635
1636
1637
1638
1639
1640
1641 
1642       
1643       
1644       
1645       
1646       
1647       
1648        <p style="font-style: normal;">q(k=nz+1) =q(k=nz) +
1649bc_q_t_val * dzu(nz+1)</p>
1650
1651
1652
1653
1654
1655
1656 
1657     
1658     
1659     
1660     
1661     
1662     
1663      </ul>
1664
1665
1666
1667
1668
1669
1670 
1671     
1672     
1673     
1674     
1675     
1676     
1677      <p style="font-style: normal;">(up tp k=nz the prognostic
1678equation for q is solved). </p>
1679
1680
1681
1682
1683
1684
1685 </td>
1686
1687
1688
1689
1690
1691
1692 </tr>
1693
1694
1695
1696
1697
1698
1699 <tr>
1700
1701
1702
1703
1704
1705
1706
1707      <td style="vertical-align: top;"> 
1708     
1709     
1710     
1711     
1712     
1713     
1714      <p><a name="bc_s_b"></a><b>bc_s_b</b></p>
1715
1716
1717
1718
1719
1720
1721 </td>
1722
1723
1724
1725
1726
1727
1728
1729      <td style="vertical-align: top;">C * 20</td>
1730
1731
1732
1733
1734
1735
1736 <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
1737
1738
1739
1740
1741
1742
1743
1744      <td style="vertical-align: top;"> 
1745     
1746     
1747     
1748     
1749     
1750     
1751      <p style="font-style: normal;">Bottom boundary condition of the
1752scalar concentration.&nbsp; </p>
1753
1754
1755
1756
1757
1758
1759 
1760     
1761     
1762     
1763     
1764     
1765     
1766      <p>Allowed values
1767are <span style="font-style: italic;">'dirichlet'</span>
1768(s(k=0) = const. = <a href="#s_surface">s_surface</a>
1769+ <a href="#s_surface_initial_change">s_surface_initial_change</a>;
1770the user may change this value during the run using user-defined code)
1771and <span style="font-style: italic;">'neumann'</span>
1772(s(k=0) =
1773s(k=1)).&nbsp; <br>
1774
1775
1776
1777
1778
1779
1780
1781When a constant surface concentration flux is used (<a href="#surface_scalarflux">surface_scalarflux</a>), <b>bc_s_b</b>
1782= <span style="font-style: italic;">'neumann'</span>
1783must be used, because otherwise the resolved scale may contribute to
1784the surface flux so that a constant value cannot be guaranteed.</p>
1785
1786
1787
1788
1789
1790
1791
1792      </td>
1793
1794
1795
1796
1797
1798
1799 </tr>
1800
1801
1802
1803
1804
1805
1806 <tr>
1807
1808
1809
1810
1811
1812
1813 <td style="vertical-align: top;"> 
1814     
1815     
1816     
1817     
1818     
1819     
1820      <p><a name="bc_s_t"></a><b>bc_s_t</b></p>
1821
1822
1823
1824
1825
1826
1827
1828      </td>
1829
1830
1831
1832
1833
1834
1835 <td style="vertical-align: top;">C * 20</td>
1836
1837
1838
1839
1840
1841
1842
1843      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1844
1845
1846
1847
1848
1849
1850
1851      <td style="vertical-align: top;"> 
1852     
1853     
1854     
1855     
1856     
1857     
1858      <p style="font-style: normal;">Top boundary condition of the
1859scalar concentration.&nbsp; </p>
1860
1861
1862
1863
1864
1865
1866 
1867     
1868     
1869     
1870     
1871     
1872     
1873      <p>Allowed are the
1874values <span style="font-style: italic;">'dirichlet'</span>
1875(s(k=nz) and s(k=nz+1) do
1876not change during the run) and <span style="font-style: italic;">'neumann'</span>.
1877With the Neumann boundary
1878condition the value of the scalar concentration gradient at the top is
1879calculated
1880from the initial scalar concentration profile (see <a href="#s_surface">s_surface</a>, <a href="#s_vertical_gradient">s_vertical_gradient</a>)
1881by: bc_s_t_val = (s_init(k=nz) - s_init(k=nz-1)) / dzu(nz).<br>
1882
1883
1884
1885
1886
1887
1888
1889Using this value (assumed constant during the run) the concentration
1890boundary values
1891are calculated as </p>
1892
1893
1894
1895
1896
1897
1898 
1899     
1900     
1901     
1902     
1903     
1904     
1905      <ul>
1906
1907
1908
1909
1910
1911
1912 
1913       
1914       
1915       
1916       
1917       
1918       
1919        <p style="font-style: normal;">s(k=nz+1) = s(k=nz) +
1920bc_s_t_val * dzu(nz+1)</p>
1921
1922
1923
1924
1925
1926
1927 
1928     
1929     
1930     
1931     
1932     
1933     
1934      </ul>
1935
1936
1937
1938
1939
1940
1941 
1942     
1943     
1944     
1945     
1946     
1947     
1948      <p style="font-style: normal;">(up to k=nz the prognostic
1949equation for the scalar concentration is
1950solved).</p>
1951
1952
1953
1954
1955
1956
1957 </td>
1958
1959
1960
1961
1962
1963
1964 </tr>
1965
1966
1967
1968
1969
1970
1971 <tr>
1972
1973
1974
1975
1976
1977
1978      <td style="vertical-align: top;"><a name="bc_sa_t"></a><span style="font-weight: bold;">bc_sa_t</span></td>
1979
1980
1981
1982
1983
1984
1985      <td style="vertical-align: top;">C * 20</td>
1986
1987
1988
1989
1990
1991
1992      <td style="vertical-align: top;"><span style="font-style: italic;">'neumann'</span></td>
1993
1994
1995
1996
1997
1998
1999      <td style="vertical-align: top;">
2000     
2001     
2002     
2003     
2004     
2005     
2006      <p style="font-style: normal;">Top boundary condition of the salinity.&nbsp; </p>
2007
2008
2009
2010
2011
2012
2013 
2014     
2015     
2016     
2017     
2018     
2019     
2020      <p>This parameter only comes into effect for ocean runs (see parameter <a href="#ocean">ocean</a>).</p>
2021
2022
2023
2024
2025
2026
2027     
2028     
2029     
2030     
2031     
2032     
2033      <p style="font-style: normal;">Allowed are the
2034values <span style="font-style: italic;">'dirichlet' </span>(sa(k=nz+1)
2035does not change during the run) and <span style="font-style: italic;">'neumann'</span>
2036(sa(k=nz+1)=sa(k=nz))<span style="font-style: italic;"></span>.&nbsp;<br>
2037
2038
2039
2040
2041
2042
2043      <br>
2044
2045
2046
2047
2048
2049
2050
2051When a constant salinity flux is used at the top boundary (<a href="chapter_4.1.html#top_salinityflux">top_salinityflux</a>),
2052      <b>bc_sa_t</b> = <span style="font-style: italic;">'neumann'</span>
2053must be used, because otherwise the resolved scale may contribute to
2054the top flux so that a constant value cannot be guaranteed.</p>
2055
2056
2057
2058
2059
2060
2061      </td>
2062
2063
2064
2065
2066
2067
2068    </tr>
2069
2070
2071
2072
2073
2074
2075    <tr>
2076
2077
2078
2079
2080
2081
2082 <td style="vertical-align: top;"> 
2083     
2084     
2085     
2086     
2087     
2088     
2089      <p><a name="bc_uv_b"></a><b>bc_uv_b</b></p>
2090
2091
2092
2093
2094
2095
2096
2097      </td>
2098
2099
2100
2101
2102
2103
2104 <td style="vertical-align: top;">C * 20</td>
2105
2106
2107
2108
2109
2110
2111
2112      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2113
2114
2115
2116
2117
2118
2119
2120      <td style="vertical-align: top;"> 
2121     
2122     
2123     
2124     
2125     
2126     
2127      <p style="font-style: normal;">Bottom boundary condition of the
2128horizontal velocity components u and v.&nbsp; </p>
2129
2130
2131
2132
2133
2134
2135 
2136     
2137     
2138     
2139     
2140     
2141     
2142      <p>Allowed
2143values are <span style="font-style: italic;">'dirichlet' </span>and
2144      <span style="font-style: italic;">'neumann'</span>. <b>bc_uv_b</b>
2145= <span style="font-style: italic;">'dirichlet'</span>
2146yields the
2147no-slip condition with u=v=0 at the bottom. Due to the staggered grid
2148u(k=0) and v(k=0) are located at z = - 0,5 * <a href="#dz">dz</a>
2149(below the bottom), while u(k=1) and v(k=1) are located at z = +0,5 *
2150dz. u=v=0 at the bottom is guaranteed using mirror boundary
2151condition:&nbsp; </p>
2152
2153
2154
2155
2156
2157
2158 
2159     
2160     
2161     
2162     
2163     
2164     
2165      <ul>
2166
2167
2168
2169
2170
2171
2172 
2173       
2174       
2175       
2176       
2177       
2178       
2179        <p style="font-style: normal;">u(k=0) = - u(k=1) and v(k=0) = -
2180v(k=1)</p>
2181
2182
2183
2184
2185
2186
2187 
2188     
2189     
2190     
2191     
2192     
2193     
2194      </ul>
2195
2196
2197
2198
2199
2200
2201 
2202     
2203     
2204     
2205     
2206     
2207     
2208      <p style="font-style: normal;">The
2209Neumann boundary condition
2210yields the free-slip condition with u(k=0) = u(k=1) and v(k=0) =
2211v(k=1).
2212With Prandtl - layer switched on, the free-slip condition is not
2213allowed (otherwise the run will be terminated)<font color="#000000">.</font></p>
2214
2215
2216
2217
2218
2219
2220
2221      </td>
2222
2223
2224
2225
2226
2227
2228 </tr>
2229
2230
2231
2232
2233
2234
2235 <tr>
2236
2237
2238
2239
2240
2241
2242 <td style="vertical-align: top;"> 
2243     
2244     
2245     
2246     
2247     
2248     
2249      <p><a name="bc_uv_t"></a><b>bc_uv_t</b></p>
2250
2251
2252
2253
2254
2255
2256
2257      </td>
2258
2259
2260
2261
2262
2263
2264 <td style="vertical-align: top;">C * 20</td>
2265
2266
2267
2268
2269
2270
2271
2272      <td style="vertical-align: top;"><span style="font-style: italic;">'dirichlet'</span></td>
2273
2274
2275
2276
2277
2278
2279
2280      <td style="vertical-align: top;"> 
2281     
2282     
2283     
2284     
2285     
2286     
2287      <p style="font-style: normal;">Top boundary condition of the
2288horizontal velocity components u and v.&nbsp; </p>
2289
2290
2291
2292
2293
2294
2295 
2296     
2297     
2298     
2299     
2300     
2301     
2302      <p>Allowed
2303values are <span style="font-style: italic;">'dirichlet'</span>, <span style="font-style: italic;">'dirichlet_0'</span>
2304and <span style="font-style: italic;">'neumann'</span>.
2305The
2306Dirichlet condition yields u(k=nz+1) = ug(nz+1) and v(k=nz+1) =
2307vg(nz+1),
2308Neumann condition yields the free-slip condition with u(k=nz+1) =
2309u(k=nz) and v(k=nz+1) = v(k=nz) (up to k=nz the prognostic equations
2310for the velocities are solved). The special condition&nbsp;<span style="font-style: italic;">'dirichlet_0'</span> can be used for channel flow, it yields the no-slip condition u(k=nz+1) = ug(nz+1) = 0 and v(k=nz+1) =
2311vg(nz+1) = 0.</p>
2312
2313
2314
2315
2316
2317
2318     
2319     
2320     
2321     
2322     
2323     
2324      <p>In the <a href="chapter_3.8.html">coupled</a> ocean executable, <a href="chapter_4.2.html#bc_uv_t">bc_uv_t</a>&nbsp;is internally set ('neumann') and does not need to be prescribed.</p>
2325
2326
2327
2328
2329
2330
2331 </td>
2332
2333
2334
2335
2336
2337
2338 </tr>
2339
2340
2341
2342
2343
2344
2345 <tr>
2346
2347
2348
2349
2350
2351
2352      <td style="vertical-align: top;"><a name="bottom_salinityflux"></a><span style="font-weight: bold;">bottom_salinityflux</span></td>
2353
2354
2355
2356
2357
2358
2359      <td style="vertical-align: top;">R</td>
2360
2361
2362
2363
2364
2365
2366      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
2367
2368
2369
2370
2371
2372
2373      <td style="vertical-align: top;">
2374     
2375     
2376     
2377     
2378     
2379     
2380      <p>Kinematic salinity flux near the surface (in psu m/s).&nbsp;</p>
2381
2382
2383
2384
2385
2386
2387This parameter only comes into effect for ocean runs (see parameter <a href="chapter_4.1.html#ocean">ocean</a>).
2388     
2389     
2390     
2391     
2392     
2393     
2394      <p>The
2395respective salinity flux value is used
2396as bottom (horizontally homogeneous) boundary condition for the salinity equation. This additionally requires that a Neumann
2397condition must be used for the salinity, which is currently the only available condition.<br>
2398
2399
2400
2401
2402
2403
2404 </p>
2405
2406
2407
2408
2409
2410
2411 </td>
2412
2413
2414
2415
2416
2417
2418    </tr>
2419
2420
2421
2422
2423
2424
2425    <tr>
2426
2427
2428
2429
2430
2431
2432
2433      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_height"></a>building_height</span></td>
2434
2435
2436
2437
2438
2439
2440
2441      <td style="vertical-align: top;">R</td>
2442
2443
2444
2445
2446
2447
2448 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2449
2450
2451
2452
2453
2454
2455 <td>Height
2456of a single building in m.<br>
2457
2458
2459
2460
2461
2462
2463 <br>
2464
2465
2466
2467
2468
2469
2470 <span style="font-weight: bold;">building_height</span> must
2471be less than the height of the model domain. This parameter requires
2472the use of&nbsp;<a href="#topography">topography</a>
2473= <span style="font-style: italic;">'single_building'</span>.</td>
2474
2475
2476
2477
2478
2479
2480
2481    </tr>
2482
2483
2484
2485
2486
2487
2488 <tr>
2489
2490
2491
2492
2493
2494
2495 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_x"></a>building_length_x</span></td>
2496
2497
2498
2499
2500
2501
2502
2503      <td style="vertical-align: top;">R</td>
2504
2505
2506
2507
2508
2509
2510 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2511
2512
2513
2514
2515
2516
2517 <td><span style="font-style: italic;"></span>Width of a single
2518building in m.<br>
2519
2520
2521
2522
2523
2524
2525 <br>
2526
2527
2528
2529
2530
2531
2532
2533Currently, <span style="font-weight: bold;">building_length_x</span>
2534must be at least <span style="font-style: italic;">3
2535*&nbsp;</span><a style="font-style: italic;" href="#dx">dx</a> and no more than <span style="font-style: italic;">(&nbsp;</span><a style="font-style: italic;" href="#nx">nx</a><span style="font-style: italic;"> - 1 ) </span><span style="font-style: italic;"> * <a href="#dx">dx</a>
2536      </span><span style="font-style: italic;">- <a href="#building_wall_left">building_wall_left</a></span>.
2537This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2538= <span style="font-style: italic;">'single_building'</span>.</td>
2539
2540
2541
2542
2543
2544
2545
2546    </tr>
2547
2548
2549
2550
2551
2552
2553 <tr>
2554
2555
2556
2557
2558
2559
2560 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_length_y"></a>building_length_y</span></td>
2561
2562
2563
2564
2565
2566
2567
2568      <td style="vertical-align: top;">R</td>
2569
2570
2571
2572
2573
2574
2575 <td style="vertical-align: top;"><span style="font-style: italic;">50.0</span></td>
2576
2577
2578
2579
2580
2581
2582 <td>Depth
2583of a single building in m.<br>
2584
2585
2586
2587
2588
2589
2590 <br>
2591
2592
2593
2594
2595
2596
2597
2598Currently, <span style="font-weight: bold;">building_length_y</span>
2599must be at least <span style="font-style: italic;">3
2600*&nbsp;</span><a style="font-style: italic;" href="#dy">dy</a> and no more than <span style="font-style: italic;">(&nbsp;</span><a style="font-style: italic;" href="#ny">ny</a><span style="font-style: italic;"> - 1 )&nbsp;</span><span style="font-style: italic;"> * <a href="#dy">dy</a></span><span style="font-style: italic;"> - <a href="#building_wall_south">building_wall_south</a></span>. This parameter requires
2601the use of&nbsp;<a href="#topography">topography</a>
2602= <span style="font-style: italic;">'single_building'</span>.</td>
2603
2604
2605
2606
2607
2608
2609
2610    </tr>
2611
2612
2613
2614
2615
2616
2617 <tr>
2618
2619
2620
2621
2622
2623
2624 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_left"></a>building_wall_left</span></td>
2625
2626
2627
2628
2629
2630
2631
2632      <td style="vertical-align: top;">R</td>
2633
2634
2635
2636
2637
2638
2639 <td style="vertical-align: top;"><span style="font-style: italic;">building centered in x-direction</span></td>
2640
2641
2642
2643
2644
2645
2646
2647      <td>x-coordinate of the left building wall (distance between the
2648left building wall and the left border of the model domain) in m.<br>
2649
2650
2651
2652
2653
2654
2655
2656      <br>
2657
2658
2659
2660
2661
2662
2663
2664Currently, <span style="font-weight: bold;">building_wall_left</span>
2665must be at least <span style="font-style: italic;">1
2666*&nbsp;</span><a style="font-style: italic;" href="#dx">dx</a> and less than <span style="font-style: italic;">( <a href="#nx">nx</a>&nbsp;
2667- 1 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a></span>.
2668This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2669= <span style="font-style: italic;">'single_building'</span>.<br>
2670
2671
2672
2673
2674
2675
2676
2677      <br>
2678
2679
2680
2681
2682
2683
2684
2685The default value&nbsp;<span style="font-weight: bold;">building_wall_left</span>
2686= <span style="font-style: italic;">( ( <a href="#nx">nx</a>&nbsp;+
26871 ) * <a href="#dx">dx</a> -&nbsp; <a href="#building_length_x">building_length_x</a> ) / 2</span>
2688centers the building in x-direction.&nbsp;<font color="#000000">Due to the staggered grid the building will be displaced by -0.5 <a href="chapter_4.1.html#dx">dx</a> in x-direction and -0.5 <a href="chapter_4.1.html#dy">dy</a> in y-direction.</font> </td>
2689
2690
2691
2692
2693
2694
2695 </tr>
2696
2697
2698
2699
2700
2701
2702 <tr>
2703
2704
2705
2706
2707
2708
2709
2710      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="building_wall_south"></a>building_wall_south</span></td>
2711
2712
2713
2714
2715
2716
2717
2718      <td style="vertical-align: top;">R</td>
2719
2720
2721
2722
2723
2724
2725 <td style="vertical-align: top;"><span style="font-style: italic;"></span><span style="font-style: italic;">building centered in y-direction</span></td>
2726
2727
2728
2729
2730
2731
2732
2733      <td>y-coordinate of the South building wall (distance between the
2734South building wall and the South border of the model domain) in m.<br>
2735
2736
2737
2738
2739
2740
2741
2742      <br>
2743
2744
2745
2746
2747
2748
2749
2750Currently, <span style="font-weight: bold;">building_wall_south</span>
2751must be at least <span style="font-style: italic;">1
2752*&nbsp;</span><a style="font-style: italic;" href="#dy">dy</a> and less than <span style="font-style: italic;">( <a href="#ny">ny</a>&nbsp;
2753- 1 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a></span>.
2754This parameter requires the use of&nbsp;<a href="#topography">topography</a>
2755= <span style="font-style: italic;">'single_building'</span>.<br>
2756
2757
2758
2759
2760
2761
2762
2763      <br>
2764
2765
2766
2767
2768
2769
2770
2771The default value&nbsp;<span style="font-weight: bold;">building_wall_south</span>
2772= <span style="font-style: italic;">( ( <a href="#ny">ny</a>&nbsp;+
27731 ) * <a href="#dy">dy</a> -&nbsp; <a href="#building_length_y">building_length_y</a> ) / 2</span>
2774centers the building in y-direction.&nbsp;<font color="#000000">Due to the staggered grid the building will be displaced by -0.5 <a href="chapter_4.1.html#dx">dx</a> in x-direction and -0.5 <a href="chapter_4.1.html#dy">dy</a> in y-direction.</font> </td>
2775
2776
2777
2778
2779
2780
2781 </tr>
2782
2783
2784
2785
2786
2787
2788 <tr>
2789
2790      <td style="vertical-align: top;"><a name="canopy_mode"></a><span style="font-weight: bold;">canopy_mode</span></td>
2791
2792      <td style="vertical-align: top;">C * 20</td>
2793
2794      <td style="vertical-align: top;"><span style="font-style: italic;">'block'</span></td>
2795
2796      <td style="vertical-align: top;">Canopy mode.<br>
2797
2798      <br>
2799
2800      <font color="#000000">
2801Besides using the default value, that will create a horizontally
2802homogeneous plant canopy that extends over the total horizontal
2803extension of the model domain, the user may add code to the user
2804interface subroutine <a href="chapter_3.5.1.html#user_init_plant_canopy">user_init_plant_canopy</a>
2805to allow further canopy&nbsp;modes. <br>
2806
2807      <br>
2808
2809The setting of <a href="#canopy_mode">canopy_mode</a> becomes only active, if&nbsp;<a href="#plant_canopy">plant_canopy</a> has been set <span style="font-style: italic;">.T.</span> and a non-zero <a href="#drag_coefficient">drag_coefficient</a> has been defined.</font></td>
2810
2811    </tr>
2812
2813    <tr><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
2814in m.<br>
2815
2816
2817
2818
2819
2820
2821 <br>
2822
2823
2824
2825
2826
2827
2828 <span style="font-weight: bold;">canyon_height</span> must
2829be less than the height of the model domain. This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2830= <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>
2831
2832
2833
2834
2835
2836
2837 <br>
2838
2839
2840
2841
2842
2843
2844
2845Currently, <span style="font-weight: bold;">canyon_width_x</span>
2846must be at least <span style="font-style: italic;">3
2847*&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>
2848      </span><span style="font-style: italic;">- <a href="chapter_4.1.html#canyon_wall_left">canyon_wall_left</a></span>.
2849This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2850= <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>
2851
2852
2853
2854
2855
2856
2857 <br>
2858
2859
2860
2861
2862
2863
2864
2865Currently, <span style="font-weight: bold;">canyon_width_y</span>
2866must be at least <span style="font-style: italic;">3
2867*&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>
2868= <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
2869left canyon wall and the left border of the model domain) in m.<br>
2870
2871
2872
2873
2874
2875
2876
2877      <br>
2878
2879
2880
2881
2882
2883
2884
2885Currently, <span style="font-weight: bold;">canyon_wall_left</span>
2886must be at least <span style="font-style: italic;">1
2887*&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;
2888- 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>.
2889This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2890= <span style="font-style: italic;">'</span><span style="font-style: italic;">single_street_canyon</span><span style="font-style: italic;">'</span>.<br>
2891
2892
2893
2894
2895
2896
2897
2898      <br>
2899
2900
2901
2902
2903
2904
2905
2906The default value <span style="font-weight: bold;">canyon_wall_left</span>
2907= <span style="font-style: italic;">( ( <a href="chapter_4.1.html#nx">nx</a>&nbsp;+
29081 ) * <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>
2909centers 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
2910South canyon wall and the South border of the model domain) in m.<br>
2911
2912
2913
2914
2915
2916
2917
2918      <br>
2919
2920
2921
2922
2923
2924
2925
2926Currently, <span style="font-weight: bold;">canyon_wall_south</span>
2927must be at least <span style="font-style: italic;">1
2928*&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;
2929- 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>.
2930This parameter requires&nbsp;<a href="chapter_4.1.html#topography">topography</a>
2931= <span style="font-style: italic;">'</span><span style="font-style: italic;">single_street_canyon</span><span style="font-style: italic;">'</span>.<br>
2932
2933
2934
2935
2936
2937
2938
2939      <br>
2940
2941
2942
2943
2944
2945
2946
2947The default value <span style="font-weight: bold;">canyon_wall_south</span>
2948= <span style="font-style: italic;">( ( <a href="chapter_4.1.html#ny">ny</a>&nbsp;+
29491 ) * <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>
2950centers the canyon in y-direction.</td></tr><tr>
2951
2952
2953
2954
2955
2956
2957
2958      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="cloud_droplets"></a>cloud_droplets</span><br>
2959
2960
2961
2962
2963
2964
2965
2966      </td>
2967
2968
2969
2970
2971
2972
2973 <td style="vertical-align: top;">L<br>
2974
2975
2976
2977
2978
2979
2980 </td>
2981
2982
2983
2984
2985
2986
2987
2988      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span><br>
2989
2990
2991
2992
2993
2994
2995 </td>
2996
2997
2998
2999
3000
3001
3002
3003      <td style="vertical-align: top;">Parameter to switch on
3004usage of cloud droplets.<br>
3005
3006
3007
3008
3009
3010
3011 <br>
3012
3013
3014
3015
3016
3017
3018
3019      <span style="font-weight: bold;"></span><span style="font-family: monospace;"></span>
3020
3021
3022
3023
3024Cloud 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
3025features (number of droplets, initial radius, etc.) can be steered with
3026the&nbsp; respective particle parameters (see e.g. <a href="#chapter_4.2.html#radius">radius</a>).
3027The real number of initial droplets in a grid cell is equal to the
3028initial 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>
3029      <span lang="en-GB"><font face="Thorndale, serif">and
3030      </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>)
3031times the <a href="#initial_weighting_factor">initial_weighting_factor</a>.<br>
3032
3033
3034
3035
3036
3037
3038
3039      <br>
3040
3041
3042
3043
3044
3045
3046
3047In case of using cloud droplets, the default condensation scheme in
3048PALM cannot be used, i.e. <a href="#cloud_physics">cloud_physics</a>
3049must be set <span style="font-style: italic;">.F.</span>.<br>
3050
3051
3052
3053
3054
3055
3056
3057      </td>
3058
3059
3060
3061
3062
3063
3064 </tr>
3065
3066
3067
3068
3069
3070
3071 <tr>
3072
3073
3074
3075
3076
3077
3078 <td style="vertical-align: top;"> 
3079     
3080     
3081     
3082     
3083     
3084     
3085      <p><a name="cloud_physics"></a><b>cloud_physics</b></p>
3086
3087
3088
3089
3090
3091
3092
3093      </td>
3094
3095
3096
3097
3098
3099
3100 <td style="vertical-align: top;">L<br>
3101
3102
3103
3104
3105
3106
3107 </td>
3108
3109
3110
3111
3112
3113
3114
3115      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
3116
3117
3118
3119
3120
3121
3122 <td style="vertical-align: top;"> 
3123     
3124     
3125     
3126     
3127     
3128     
3129      <p>Parameter to switch
3130on the condensation scheme.&nbsp; </p>
3131
3132
3133
3134
3135
3136
3137
3138For <b>cloud_physics =</b> <span style="font-style: italic;">.TRUE.</span>, equations
3139for the
3140liquid water&nbsp;
3141content and the liquid water potential temperature are solved instead
3142of those for specific humidity and potential temperature. Note
3143that a grid volume is assumed to be either completely saturated or
3144completely
3145unsaturated (0%-or-100%-scheme). A simple precipitation scheme can
3146additionally be switched on with parameter <a href="#precipitation">precipitation</a>.
3147Also cloud-top cooling by longwave radiation can be utilized (see <a href="#radiation">radiation</a>)<br>
3148
3149
3150
3151
3152
3153
3154 <b><br>
3155
3156
3157
3158
3159
3160
3161
3162cloud_physics =</b> <span style="font-style: italic;">.TRUE.
3163      </span>requires&nbsp;<a href="#humidity">humidity</a>
3164=<span style="font-style: italic;"> .TRUE.</span> .<br>
3165
3166
3167
3168
3169
3170
3171
3172Detailed information about the condensation scheme is given in the
3173description of the <a href="http://www.muk.uni-hannover.de/%7Eraasch/PALM-1/Dokumentationen/Cloud_physics/wolken.pdf">cloud
3174physics module</a> (pdf-file, only in German).<br>
3175
3176
3177
3178
3179
3180
3181 <br>
3182
3183
3184
3185
3186
3187
3188
3189This condensation scheme is not allowed if cloud droplets are simulated
3190explicitly (see <a href="#cloud_droplets">cloud_droplets</a>).<br>
3191
3192
3193
3194
3195
3196
3197
3198      </td>
3199
3200
3201
3202
3203
3204
3205 </tr>
3206
3207
3208
3209
3210
3211
3212 <tr>
3213
3214
3215
3216
3217
3218
3219 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="conserve_volume_flow"></a>conserve_volume_flow</span></td>
3220
3221
3222
3223
3224
3225
3226
3227      <td style="vertical-align: top;">L</td>
3228
3229
3230
3231
3232
3233
3234 <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
3235
3236
3237
3238
3239
3240
3241 <td>Conservation
3242of volume flow in x- and y-direction.<br>
3243
3244
3245
3246
3247
3248
3249 <br>
3250
3251
3252
3253
3254
3255
3256 <span style="font-weight: bold;">conserve_volume_flow</span>
3257= <span style="font-style: italic;">.T.</span>
3258guarantees that the volume flow through the xz- or yz-cross-section of
3259the total model domain remains constant (equal to the initial value at
3260t=0) throughout the run.<br><br>Note that&nbsp;<span style="font-weight: bold;">conserve_volume_flow</span>
3261= <span style="font-style: italic;">.T.</span> requires <a href="#dp_external">dp_external</a> = <span style="font-style: italic;">.F.</span> .<br>
3262
3263
3264
3265
3266
3267
3268
3269      </td>
3270
3271
3272
3273
3274
3275
3276 </tr>
3277
3278
3279
3280
3281
3282
3283 <tr>
3284
3285      <td style="vertical-align: top;"><a name="cthf"></a><span style="font-weight: bold;">cthf</span></td>
3286
3287      <td style="vertical-align: top;">R</td>
3288
3289      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3290
3291      <td style="vertical-align: top;">Average heat flux that is prescribed at the top of the plant canopy.<br>
3292
3293
3294      <br>
3295
3296
3297If <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>
3298
3299
3300It is assumed that solar radiation penetrates the canopy and warms the
3301foliage which, in turn, warms the air in contact with it. <br>
3302
3303
3304Note: Instead of using the value prescribed by <a href="#surface_heatflux">surface_heatflux</a>,
3305the near surface heat flux is determined from an exponential function
3306that is dependent on the cumulative leaf_area_index (Shaw and Schumann
3307(1992, Boundary Layer Meteorol., 61, 47-64)).</td>
3308
3309    </tr>
3310
3311    <tr>
3312
3313
3314
3315
3316
3317
3318 <td style="vertical-align: top;"> 
3319     
3320     
3321     
3322     
3323     
3324     
3325      <p><a name="cut_spline_overshoot"></a><b>cut_spline_overshoot</b></p>
3326
3327
3328
3329
3330
3331
3332
3333      </td>
3334
3335
3336
3337
3338
3339
3340 <td style="vertical-align: top;">L</td>
3341
3342
3343
3344
3345
3346
3347
3348      <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span></td>
3349
3350
3351
3352
3353
3354
3355 <td style="vertical-align: top;"> 
3356     
3357     
3358     
3359     
3360     
3361     
3362      <p>Cuts off of
3363so-called overshoots, which can occur with the
3364upstream-spline scheme.&nbsp; </p>
3365
3366
3367
3368
3369
3370
3371 
3372     
3373     
3374     
3375     
3376     
3377     
3378      <p><font color="#000000">The cubic splines tend to overshoot in
3379case of discontinuous changes of variables between neighbouring grid
3380points.</font><font color="#ff0000"> </font><font color="#000000">This
3381may lead to errors in calculating the advection tendency.</font>
3382Choice
3383of <b>cut_spline_overshoot</b> = <i>.TRUE.</i>
3384(switched on by
3385default)
3386allows variable values not to exceed an interval defined by the
3387respective adjacent grid points. This interval can be adjusted
3388seperately for every prognostic variable (see initialization parameters
3389      <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>,
3390etc.). This might be necessary in case that the
3391default interval has a non-tolerable effect on the model
3392results.&nbsp; </p>
3393
3394
3395
3396
3397
3398
3399 
3400     
3401     
3402     
3403     
3404     
3405     
3406      <p>Overshoots may also be removed
3407using the parameters <a href="#ups_limit_e">ups_limit_e</a>,
3408      <a href="#ups_limit_pt">ups_limit_pt</a>,
3409etc. as well as by applying a long-filter (see <a href="#long_filter_factor">long_filter_factor</a>).</p>
3410
3411
3412
3413
3414
3415
3416
3417      </td>
3418
3419
3420
3421
3422
3423
3424 </tr>
3425
3426
3427
3428
3429
3430
3431 <tr>
3432
3433
3434
3435
3436
3437
3438 <td style="vertical-align: top;"> 
3439     
3440     
3441     
3442     
3443     
3444     
3445      <p><a name="damp_level_1d"></a><b>damp_level_1d</b></p>
3446
3447
3448
3449
3450
3451
3452
3453      </td>
3454
3455
3456
3457
3458
3459
3460 <td style="vertical-align: top;">R</td>
3461
3462
3463
3464
3465
3466
3467
3468      <td style="vertical-align: top;"><span style="font-style: italic;">zu(nz+1)</span></td>
3469
3470
3471
3472
3473
3474
3475
3476      <td style="vertical-align: top;"> 
3477     
3478     
3479     
3480     
3481     
3482     
3483      <p>Height where
3484the damping layer begins in the 1d-model
3485(in m).&nbsp; </p>
3486
3487
3488
3489
3490
3491
3492 
3493     
3494     
3495     
3496     
3497     
3498     
3499      <p>This parameter is used to
3500switch on a damping layer for the
35011d-model, which is generally needed for the damping of inertia
3502oscillations. Damping is done by gradually increasing the value
3503of the eddy diffusivities about 10% per vertical grid level
3504(starting with the value at the height given by <b>damp_level_1d</b>,
3505or possibly from the next grid pint above), i.e. K<sub>m</sub>(k+1)
3506=
35071.1 * K<sub>m</sub>(k).
3508The values of K<sub>m</sub> are limited to 10 m**2/s at
3509maximum.&nbsp; <br>
3510
3511
3512
3513
3514
3515
3516
3517This parameter only comes into effect if the 1d-model is switched on
3518for
3519the initialization of the 3d-model using <a href="#initializing_actions">initializing_actions</a>
3520= <span style="font-style: italic;">'set_1d-model_profiles'</span>.
3521      <br>
3522
3523
3524
3525
3526
3527
3528 </p>
3529
3530
3531
3532
3533
3534
3535 </td>
3536
3537
3538
3539
3540
3541
3542 </tr>
3543
3544
3545
3546
3547
3548
3549 <tr>
3550
3551
3552
3553
3554
3555
3556 <td style="vertical-align: top;"><a name="dissipation_1d"></a><span style="font-weight: bold;">dissipation_1d</span><br>
3557
3558
3559
3560
3561
3562
3563
3564      </td>
3565
3566
3567
3568
3569
3570
3571 <td style="vertical-align: top;">C*20<br>
3572
3573
3574
3575
3576
3577
3578
3579      </td>
3580
3581
3582
3583
3584
3585
3586 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
3587
3588
3589
3590
3591
3592
3593 <span style="font-style: italic;">model'</span><br>
3594
3595
3596
3597
3598
3599
3600 </td>
3601
3602
3603
3604
3605
3606
3607
3608      <td style="vertical-align: top;">Calculation method for
3609the energy dissipation term in the TKE equation of the 1d-model.<br>
3610
3611
3612
3613
3614
3615
3616
3617      <br>
3618
3619
3620
3621
3622
3623
3624
3625By default the dissipation is calculated as in the 3d-model using diss
3626= (0.19 + 0.74 * l / l_grid) * e**1.5 / l.<br>
3627
3628
3629
3630
3631
3632
3633 <br>
3634
3635
3636
3637
3638
3639
3640
3641Setting <span style="font-weight: bold;">dissipation_1d</span>
3642= <span style="font-style: italic;">'detering'</span>
3643forces the dissipation to be calculated as diss = 0.064 * e**1.5 / l.<br>
3644
3645
3646
3647
3648
3649
3650
3651      </td>
3652
3653
3654
3655
3656
3657
3658 </tr>
3659    <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
3660parameter is used to switch on/off an external pressure gradient as
3661driving force. The external pressure gradient is controlled by the
3662parameters <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="l#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
3663limit 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
3664must hold the condition zu(0) &lt;= <b>dp_level_b</b>
3665&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
3666that there is no upper limit of the vertical range because the external
3667pressure 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>
3668
3669
3670
3671
3672
3673
3674    <tr>
3675
3676      <td style="vertical-align: top;"><a name="drag_coefficient"></a><span style="font-weight: bold;">drag_coefficient</span></td>
3677
3678      <td style="vertical-align: top;">R</td>
3679
3680      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3681
3682      <td style="vertical-align: top;">Drag coefficient used in the plant canopy model.<br>
3683
3684      <br>
3685
3686This 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>
3687
3688    </tr>
3689
3690    <tr>
3691
3692
3693
3694
3695
3696
3697 <td style="vertical-align: top;"> 
3698     
3699     
3700     
3701     
3702     
3703     
3704      <p><a name="dt"></a><b>dt</b></p>
3705
3706
3707
3708
3709
3710
3711 </td>
3712
3713
3714
3715
3716
3717
3718
3719      <td style="vertical-align: top;">R</td>
3720
3721
3722
3723
3724
3725
3726 <td style="vertical-align: top;"><span style="font-style: italic;">variable</span></td>
3727
3728
3729
3730
3731
3732
3733
3734      <td style="vertical-align: top;"> 
3735     
3736     
3737     
3738     
3739     
3740     
3741      <p>Time step for
3742the 3d-model (in s).&nbsp; </p>
3743
3744
3745
3746
3747
3748
3749 
3750     
3751     
3752     
3753     
3754     
3755     
3756      <p>By default, (i.e.
3757if a Runge-Kutta scheme is used, see <a href="#timestep_scheme">timestep_scheme</a>)
3758the value of the time step is calculating after each time step
3759(following the time step criteria) and
3760used for the next step.</p>
3761
3762
3763
3764
3765
3766
3767 
3768     
3769     
3770     
3771     
3772     
3773     
3774      <p>If the user assigns <b>dt</b>
3775a value, then the time step is
3776fixed to this value throughout the whole run (whether it fulfills the
3777time step
3778criteria or not). However, changes are allowed for restart runs,
3779because <b>dt</b> can also be used as a <a href="chapter_4.2.html#dt_laufparameter">run
3780parameter</a>.&nbsp; </p>
3781
3782
3783
3784
3785
3786
3787 
3788     
3789     
3790     
3791     
3792     
3793     
3794      <p>In case that the
3795calculated time step meets the condition<br>
3796
3797
3798
3799
3800
3801
3802 </p>
3803
3804
3805
3806
3807
3808
3809 
3810     
3811     
3812     
3813     
3814     
3815     
3816      <ul>
3817
3818
3819
3820
3821
3822
3823
3824       
3825       
3826       
3827       
3828       
3829       
3830        <p><b>dt</b> &lt; 0.00001 * <a href="chapter_4.2.html#dt_max">dt_max</a> (with dt_max
3831= 20.0)</p>
3832
3833
3834
3835
3836
3837
3838 
3839     
3840     
3841     
3842     
3843     
3844     
3845      </ul>
3846
3847
3848
3849
3850
3851
3852 
3853     
3854     
3855     
3856     
3857     
3858     
3859      <p>the simulation will be
3860aborted. Such situations usually arise
3861in case of any numerical problem / instability which causes a
3862non-realistic increase of the wind speed.&nbsp; </p>
3863
3864
3865
3866
3867
3868
3869 
3870     
3871     
3872     
3873     
3874     
3875     
3876      <p>A
3877small time step due to a large mean horizontal windspeed
3878speed may be enlarged by using a coordinate transformation (see <a href="#galilei_transformation">galilei_transformation</a>),
3879in order to spare CPU time.<br>
3880
3881
3882
3883
3884
3885
3886 </p>
3887
3888
3889
3890
3891
3892
3893 
3894     
3895     
3896     
3897     
3898     
3899     
3900      <p>If the
3901leapfrog timestep scheme is used (see <a href="#timestep_scheme">timestep_scheme</a>)
3902a temporary time step value dt_new is calculated first, with dt_new = <a href="chapter_4.2.html#fcl_factor">cfl_factor</a>
3903* dt_crit where dt_crit is the maximum timestep allowed by the CFL and
3904diffusion condition. Next it is examined whether dt_new exceeds or
3905falls below the
3906value of the previous timestep by at
3907least +5 % / -2%. If it is smaller, <span style="font-weight: bold;">dt</span>
3908= dt_new is immediately used for the next timestep. If it is larger,
3909then <span style="font-weight: bold;">dt </span>=
39101.02 * dt_prev
3911(previous timestep) is used as the new timestep, however the time
3912step is only increased if the last change of the time step is dated
3913back at
3914least 30 iterations. If dt_new is located in the interval mentioned
3915above, then dt
3916does not change at all. By doing so, permanent time step changes as
3917well as large
3918sudden changes (increases) in the time step are avoided.</p>
3919
3920
3921
3922
3923
3924
3925 </td>
3926
3927
3928
3929
3930
3931
3932
3933    </tr>
3934
3935
3936
3937
3938
3939
3940 <tr>
3941
3942
3943
3944
3945
3946
3947 <td style="vertical-align: top;">
3948     
3949     
3950     
3951     
3952     
3953     
3954      <p><a name="dt_pr_1d"></a><b>dt_pr_1d</b></p>
3955
3956
3957
3958
3959
3960
3961
3962      </td>
3963
3964
3965
3966
3967
3968
3969 <td style="vertical-align: top;">R</td>
3970
3971
3972
3973
3974
3975
3976
3977      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
3978
3979
3980
3981
3982
3983
3984
3985      <td style="vertical-align: top;"> 
3986     
3987     
3988     
3989     
3990     
3991     
3992      <p>Temporal
3993interval of vertical profile output of the 1D-model
3994(in s).&nbsp; </p>
3995
3996
3997
3998
3999
4000
4001 
4002     
4003     
4004     
4005     
4006     
4007     
4008      <p>Data are written in ASCII
4009format to file <a href="chapter_3.4.html#LIST_PROFIL_1D">LIST_PROFIL_1D</a>.
4010This parameter is only in effect if the 1d-model has been switched on
4011for the
4012initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4013= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4014
4015
4016
4017
4018
4019
4020
4021      </td>
4022
4023
4024
4025
4026
4027
4028 </tr>
4029
4030
4031
4032
4033
4034
4035 <tr>
4036
4037
4038
4039
4040
4041
4042 <td style="vertical-align: top;"> 
4043     
4044     
4045     
4046     
4047     
4048     
4049      <p><a name="dt_run_control_1d"></a><b>dt_run_control_1d</b></p>
4050
4051
4052
4053
4054
4055
4056
4057      </td>
4058
4059
4060
4061
4062
4063
4064 <td style="vertical-align: top;">R</td>
4065
4066
4067
4068
4069
4070
4071
4072      <td style="vertical-align: top;"><span style="font-style: italic;">60.0</span></td>
4073
4074
4075
4076
4077
4078
4079 <td style="vertical-align: top;"> 
4080     
4081     
4082     
4083     
4084     
4085     
4086      <p>Temporal interval of
4087runtime control output of the 1d-model
4088(in s).&nbsp; </p>
4089
4090
4091
4092
4093
4094
4095 
4096     
4097     
4098     
4099     
4100     
4101     
4102      <p>Data are written in ASCII
4103format to file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
4104This parameter is only in effect if the 1d-model is switched on for the
4105initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4106= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4107
4108
4109
4110
4111
4112
4113
4114      </td>
4115
4116
4117
4118
4119
4120
4121 </tr>
4122
4123
4124
4125
4126
4127
4128 <tr>
4129
4130
4131
4132
4133
4134
4135 <td style="vertical-align: top;"> 
4136     
4137     
4138     
4139     
4140     
4141     
4142      <p><a name="dx"></a><b>dx</b></p>
4143
4144
4145
4146
4147
4148
4149
4150      </td>
4151
4152
4153
4154
4155
4156
4157 <td style="vertical-align: top;">R</td>
4158
4159
4160
4161
4162
4163
4164
4165      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4166
4167
4168
4169
4170
4171
4172 <td style="vertical-align: top;"> 
4173     
4174     
4175     
4176     
4177     
4178     
4179      <p>Horizontal grid
4180spacing along the x-direction (in m).&nbsp; </p>
4181
4182
4183
4184
4185
4186
4187 
4188     
4189     
4190     
4191     
4192     
4193     
4194      <p>Along
4195x-direction only a constant grid spacing is allowed.</p>
4196
4197
4198
4199
4200
4201
4202     
4203     
4204     
4205     
4206     
4207     
4208      <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>
4209and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4210
4211
4212
4213
4214
4215
4216 </td>
4217
4218
4219
4220
4221
4222
4223
4224    </tr>
4225
4226
4227
4228
4229
4230
4231 <tr>
4232
4233
4234
4235
4236
4237
4238 <td style="vertical-align: top;">
4239     
4240     
4241     
4242     
4243     
4244     
4245      <p><a name="dy"></a><b>dy</b></p>
4246
4247
4248
4249
4250
4251
4252
4253      </td>
4254
4255
4256
4257
4258
4259
4260 <td style="vertical-align: top;">R</td>
4261
4262
4263
4264
4265
4266
4267
4268      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4269
4270
4271
4272
4273
4274
4275 <td style="vertical-align: top;"> 
4276     
4277     
4278     
4279     
4280     
4281     
4282      <p>Horizontal grid
4283spacing along the y-direction (in m).&nbsp; </p>
4284
4285
4286
4287
4288
4289
4290 
4291     
4292     
4293     
4294     
4295     
4296     
4297      <p>Along y-direction only a constant grid spacing is allowed.</p>
4298
4299
4300
4301
4302
4303
4304     
4305     
4306     
4307     
4308     
4309     
4310      <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>
4311and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4312
4313
4314
4315
4316
4317
4318 </td>
4319
4320
4321
4322
4323
4324
4325
4326    </tr>
4327
4328
4329
4330
4331
4332
4333 <tr>
4334
4335
4336
4337
4338
4339
4340 <td style="vertical-align: top;">
4341     
4342     
4343     
4344     
4345     
4346     
4347      <p><a name="dz"></a><b>dz</b></p>
4348
4349
4350
4351
4352
4353
4354
4355      </td>
4356
4357
4358
4359
4360
4361
4362 <td style="vertical-align: top;">R</td>
4363
4364
4365
4366
4367
4368
4369
4370      <td style="vertical-align: top;"><br>
4371
4372
4373
4374
4375
4376
4377 </td>
4378
4379
4380
4381
4382
4383
4384 <td style="vertical-align: top;"> 
4385     
4386     
4387     
4388     
4389     
4390     
4391      <p>Vertical grid
4392spacing (in m).&nbsp; </p>
4393
4394
4395
4396
4397
4398
4399 
4400     
4401     
4402     
4403     
4404     
4405     
4406      <p>This parameter must be
4407assigned by the user, because no
4408default value is given.<br>
4409
4410
4411
4412
4413
4414
4415 </p>
4416
4417
4418
4419
4420
4421
4422 
4423     
4424     
4425     
4426     
4427     
4428     
4429      <p>By default, the
4430model uses constant grid spacing along z-direction, but it can be
4431stretched using the parameters <a href="#dz_stretch_level">dz_stretch_level</a>
4432and <a href="#dz_stretch_factor">dz_stretch_factor</a>.
4433In case of stretching, a maximum allowed grid spacing can be given by <a href="#dz_max">dz_max</a>.<br>
4434
4435
4436
4437
4438
4439
4440 </p>
4441
4442
4443
4444
4445
4446
4447 
4448     
4449     
4450     
4451     
4452     
4453     
4454      <p>Assuming
4455a constant <span style="font-weight: bold;">dz</span>,
4456the scalar levels (zu) are calculated directly by:&nbsp; </p>
4457
4458
4459
4460
4461
4462
4463
4464     
4465     
4466     
4467     
4468     
4469     
4470      <ul>
4471
4472
4473
4474
4475
4476
4477 
4478       
4479       
4480       
4481       
4482       
4483       
4484        <p>zu(0) = - dz * 0.5&nbsp; <br>
4485
4486
4487
4488
4489
4490
4491
4492zu(1) = dz * 0.5</p>
4493
4494
4495
4496
4497
4498
4499 
4500     
4501     
4502     
4503     
4504     
4505     
4506      </ul>
4507
4508
4509
4510
4511
4512
4513 
4514     
4515     
4516     
4517     
4518     
4519     
4520      <p>The w-levels lie
4521half between them:&nbsp; </p>
4522
4523
4524
4525
4526
4527
4528 
4529     
4530     
4531     
4532     
4533     
4534     
4535      <ul>
4536
4537
4538
4539
4540
4541
4542 
4543       
4544       
4545       
4546       
4547       
4548       
4549        <p>zw(k) =
4550( zu(k) + zu(k+1) ) * 0.5</p>
4551
4552
4553
4554
4555
4556
4557 
4558     
4559     
4560     
4561     
4562     
4563     
4564      </ul>
4565
4566
4567
4568
4569
4570
4571 </td>
4572
4573
4574
4575
4576
4577
4578 </tr>
4579
4580
4581
4582
4583
4584
4585
4586    <tr>
4587
4588
4589
4590
4591
4592
4593      <td style="vertical-align: top;"><a name="dz_max"></a><span style="font-weight: bold;">dz_max</span></td>
4594
4595
4596
4597
4598
4599
4600      <td style="vertical-align: top;">R</td>
4601
4602
4603
4604
4605
4606
4607      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4608
4609
4610
4611
4612
4613
4614      <td style="vertical-align: top;">Allowed maximum vertical grid
4615spacing (in m).<br>
4616
4617
4618
4619
4620
4621
4622      <br>
4623
4624
4625
4626
4627
4628
4629If the vertical grid is stretched
4630(see <a href="#dz_stretch_factor">dz_stretch_factor</a>
4631and <a href="#dz_stretch_level">dz_stretch_level</a>),
4632      <span style="font-weight: bold;">dz_max</span> can
4633be used to limit the vertical grid spacing.</td>
4634
4635
4636
4637
4638
4639
4640    </tr>
4641
4642
4643
4644
4645
4646
4647    <tr>
4648
4649
4650
4651
4652
4653
4654
4655      <td style="vertical-align: top;"> 
4656     
4657     
4658     
4659     
4660     
4661     
4662      <p><a name="dz_stretch_factor"></a><b>dz_stretch_factor</b></p>
4663
4664
4665
4666
4667
4668
4669
4670      </td>
4671
4672
4673
4674
4675
4676
4677 <td style="vertical-align: top;">R</td>
4678
4679
4680
4681
4682
4683
4684
4685      <td style="vertical-align: top;"><span style="font-style: italic;">1.08</span></td>
4686
4687
4688
4689
4690
4691
4692 <td style="vertical-align: top;"> 
4693     
4694     
4695     
4696     
4697     
4698     
4699      <p>Stretch factor for a
4700vertically stretched grid (see <a href="#dz_stretch_level">dz_stretch_level</a>).&nbsp;
4701      </p>
4702
4703
4704
4705
4706
4707
4708 
4709     
4710     
4711     
4712     
4713     
4714     
4715      <p>The stretch factor should not exceed a value of
4716approx. 1.10 -
47171.12, otherwise the discretization errors due to the stretched grid not
4718negligible any more. (refer Kalnay de Rivas)</p>
4719
4720
4721
4722
4723
4724
4725 </td>
4726
4727
4728
4729
4730
4731
4732 </tr>
4733
4734
4735
4736
4737
4738
4739
4740    <tr>
4741
4742
4743
4744
4745
4746
4747 <td style="vertical-align: top;"> 
4748     
4749     
4750     
4751     
4752     
4753     
4754      <p><a name="dz_stretch_level"></a><b>dz_stretch_level</b></p>
4755
4756
4757
4758
4759
4760
4761
4762      </td>
4763
4764
4765
4766
4767
4768
4769 <td style="vertical-align: top;">R</td>
4770
4771
4772
4773
4774
4775
4776
4777      <td style="vertical-align: top;"><span style="font-style: italic;">100000.0</span><br>
4778
4779
4780
4781
4782
4783
4784 </td>
4785
4786
4787
4788
4789
4790
4791
4792      <td style="vertical-align: top;"> 
4793     
4794     
4795     
4796     
4797     
4798     
4799      <p>Height level
4800above/below which the grid is to be stretched
4801vertically (in m).&nbsp; </p>
4802
4803
4804
4805
4806
4807
4808 
4809     
4810     
4811     
4812     
4813     
4814     
4815      <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
4816vertically. The vertical grid
4817spacings <a href="#dz">dz</a>
4818above this level are calculated as&nbsp; </p>
4819
4820
4821
4822
4823
4824
4825 
4826     
4827     
4828     
4829     
4830     
4831     
4832      <ul>
4833
4834
4835
4836
4837
4838
4839 
4840       
4841       
4842       
4843       
4844       
4845       
4846        <p><b>dz</b>(k+1)
4847= <b>dz</b>(k) * <a href="#dz_stretch_factor">dz_stretch_factor</a></p>
4848
4849
4850
4851
4852
4853
4854
4855     
4856     
4857     
4858     
4859     
4860     
4861      </ul>
4862
4863
4864
4865
4866
4867
4868 
4869     
4870     
4871     
4872     
4873     
4874     
4875      <p>and used as spacings for the scalar levels (zu).
4876The
4877w-levels are then defined as:&nbsp; </p>
4878
4879
4880
4881
4882
4883
4884 
4885     
4886     
4887     
4888     
4889     
4890     
4891      <ul>
4892
4893
4894
4895
4896
4897
4898 
4899       
4900       
4901       
4902       
4903       
4904       
4905        <p>zw(k)
4906= ( zu(k) + zu(k+1) ) * 0.5.
4907
4908 
4909     
4910      </p>
4911
4912
4913
4914
4915     
4916     
4917     
4918     
4919      </ul>
4920
4921
4922
4923
4924     
4925     
4926     
4927     
4928      <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
4929vertically. The vertical grid
4930spacings <a href="chapter_4.1.html#dz">dz</a> below this level are calculated correspondingly as
4931
4932 
4933     
4934      </p>
4935
4936
4937
4938
4939     
4940     
4941     
4942     
4943      <ul>
4944
4945
4946
4947
4948       
4949       
4950       
4951       
4952        <p><b>dz</b>(k-1)
4953= <b>dz</b>(k) * <a href="chapter_4.1.html#dz_stretch_factor">dz_stretch_factor</a>.</p>
4954
4955
4956
4957
4958     
4959     
4960     
4961     
4962      </ul>
4963
4964
4965
4966
4967
4968
4969 </td>
4970
4971
4972
4973
4974
4975
4976 </tr>
4977
4978
4979
4980
4981
4982
4983
4984    <tr>
4985
4986
4987
4988
4989
4990      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_init"></a>e_init</span></td>
4991
4992
4993
4994
4995
4996      <td style="vertical-align: top;">R</td>
4997
4998
4999
5000
5001
5002      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5003
5004
5005
5006
5007
5008      <td>Initial subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5009
5010
5011
5012
5013
5014
5015
5016      <br>
5017
5018
5019
5020
5021
5022
5023This
5024option 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>
5025
5026
5027
5028
5029
5030    </tr>
5031
5032
5033
5034
5035
5036    <tr>
5037
5038
5039
5040
5041
5042
5043 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_min"></a>e_min</span></td>
5044
5045
5046
5047
5048
5049
5050
5051      <td style="vertical-align: top;">R</td>
5052
5053
5054
5055
5056
5057
5058 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5059
5060
5061
5062
5063
5064
5065 <td>Minimum
5066subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5067
5068
5069
5070
5071
5072
5073
5074      <br>
5075
5076
5077
5078
5079
5080
5081This
5082option&nbsp;adds artificial viscosity to the flow by ensuring that
5083the
5084subgrid-scale TKE does not fall below the minimum threshold <span style="font-weight: bold;">e_min</span>.</td>
5085
5086
5087
5088
5089
5090
5091 </tr>
5092
5093
5094
5095
5096
5097
5098
5099    <tr>
5100
5101
5102
5103
5104
5105
5106 <td style="vertical-align: top;"> 
5107     
5108     
5109     
5110     
5111     
5112     
5113      <p><a name="end_time_1d"></a><b>end_time_1d</b></p>
5114
5115
5116
5117
5118
5119
5120
5121      </td>
5122
5123
5124
5125
5126
5127
5128 <td style="vertical-align: top;">R</td>
5129
5130
5131
5132
5133
5134
5135
5136      <td style="vertical-align: top;"><span style="font-style: italic;">864000.0</span><br>
5137
5138
5139
5140
5141
5142
5143 </td>
5144
5145
5146
5147
5148
5149
5150
5151      <td style="vertical-align: top;"> 
5152     
5153     
5154     
5155     
5156     
5157     
5158      <p>Time to be
5159simulated for the 1d-model (in s).&nbsp; </p>
5160
5161
5162
5163
5164
5165
5166 
5167     
5168     
5169     
5170     
5171     
5172     
5173      <p>The
5174default value corresponds to a simulated time of 10 days.
5175Usually, after such a period the inertia oscillations have completely
5176decayed and the solution of the 1d-model can be regarded as stationary
5177(see <a href="#damp_level_1d">damp_level_1d</a>).
5178This parameter is only in effect if the 1d-model is switched on for the
5179initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
5180= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
5181
5182
5183
5184
5185
5186
5187
5188      </td>
5189
5190
5191
5192
5193
5194
5195 </tr>
5196
5197
5198
5199
5200
5201
5202 <tr>
5203
5204
5205
5206
5207
5208
5209 <td style="vertical-align: top;"> 
5210     
5211     
5212     
5213     
5214     
5215     
5216      <p><a name="fft_method"></a><b>fft_method</b></p>
5217
5218
5219
5220
5221
5222
5223
5224      </td>
5225
5226
5227
5228
5229
5230
5231 <td style="vertical-align: top;">C * 20</td>
5232
5233
5234
5235
5236
5237
5238
5239      <td style="vertical-align: top;"><span style="font-style: italic;">'system-</span><br style="font-style: italic;">
5240
5241
5242
5243
5244
5245
5246 <span style="font-style: italic;">specific'</span></td>
5247
5248
5249
5250
5251
5252
5253
5254      <td style="vertical-align: top;"> 
5255     
5256     
5257     
5258     
5259     
5260     
5261      <p>FFT-method to
5262be used.<br>
5263
5264
5265
5266
5267
5268
5269 </p>
5270
5271
5272
5273
5274
5275
5276 
5277     
5278     
5279     
5280     
5281     
5282     
5283      <p><br>
5284
5285
5286
5287
5288
5289
5290
5291The fast fourier transformation (FFT) is used for solving the
5292perturbation pressure equation with a direct method (see <a href="chapter_4.2.html#psolver">psolver</a>)
5293and for calculating power spectra (see optional software packages,
5294section <a href="chapter_4.2.html#spectra_package">4.2</a>).</p>
5295
5296
5297
5298
5299
5300
5301
5302     
5303     
5304     
5305     
5306     
5307     
5308      <p><br>
5309
5310
5311
5312
5313
5314
5315
5316By default, system-specific, optimized routines from external
5317vendor libraries are used. However, these are available only on certain
5318computers and there are more or less severe restrictions concerning the
5319number of gridpoints to be used with them.<br>
5320
5321
5322
5323
5324
5325
5326 </p>
5327
5328
5329
5330
5331
5332
5333 
5334     
5335     
5336     
5337     
5338     
5339     
5340      <p>There
5341are two other PALM internal methods available on every
5342machine (their respective source code is part of the PALM source code):</p>
5343
5344
5345
5346
5347
5348
5349
5350     
5351     
5352     
5353     
5354     
5355     
5356      <p>1.: The <span style="font-weight: bold;">Temperton</span>-method
5357from Clive Temperton (ECWMF) which is computationally very fast and
5358switched on with <b>fft_method</b> = <span style="font-style: italic;">'temperton-algorithm'</span>.
5359The number of horizontal gridpoints (nx+1, ny+1) to be used with this
5360method must be composed of prime factors 2, 3 and 5.<br>
5361
5362
5363
5364
5365
5366
5367 </p>
5368
5369
5370
5371
5372
5373
5374
53752.: The <span style="font-weight: bold;">Singleton</span>-method
5376which is very slow but has no restrictions concerning the number of
5377gridpoints to be used with, switched on with <b>fft_method</b>
5378= <span style="font-style: italic;">'singleton-algorithm'</span>.
5379      </td>
5380
5381
5382
5383
5384
5385
5386 </tr>
5387
5388
5389
5390
5391
5392
5393 <tr>
5394
5395
5396
5397
5398
5399
5400 <td style="vertical-align: top;"> 
5401     
5402     
5403     
5404     
5405     
5406     
5407      <p><a name="galilei_transformation"></a><b>galilei_transformation</b></p>
5408
5409
5410
5411
5412
5413
5414
5415      </td>
5416
5417
5418
5419
5420
5421
5422 <td style="vertical-align: top;">L</td>
5423
5424
5425
5426
5427
5428
5429
5430      <td style="vertical-align: top;"><i>.F.</i></td>
5431
5432
5433
5434
5435
5436
5437
5438      <td style="vertical-align: top;">Application of a
5439Galilei-transformation to the
5440coordinate
5441system of the model.<br>
5442
5443
5444
5445
5446
5447
5448     
5449     
5450     
5451     
5452     
5453     
5454      <p>With <b>galilei_transformation</b>
5455= <i>.T.,</i> a so-called
5456Galilei-transformation is switched on which ensures that the coordinate
5457system of the model is moved along with the geostrophical wind.
5458Alternatively, the model domain can be moved along with the averaged
5459horizontal wind (see <a href="#use_ug_for_galilei_tr">use_ug_for_galilei_tr</a>,
5460this can and will naturally change in time). With this method,
5461numerical inaccuracies of the Piascek - Williams - scheme (concerns in
5462particular the momentum advection) are minimized. Beyond that, in the
5463majority of cases the lower relative velocities in the moved system
5464permit a larger time step (<a href="#dt">dt</a>).
5465Switching the transformation on is only worthwhile if the geostrophical
5466wind (ug, vg)
5467and the averaged horizontal wind clearly deviate from the value 0. In
5468each case, the distance the coordinate system has been moved is written
5469to the file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.&nbsp;
5470      </p>
5471
5472
5473
5474
5475
5476
5477 
5478     
5479     
5480     
5481     
5482     
5483     
5484      <p>Non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
5485and <a href="#bc_ns">bc_ns</a>), the specification
5486of a gestrophic
5487wind that is not constant with height
5488as well as e.g. stationary inhomogeneities at the bottom boundary do
5489not allow the use of this transformation.</p>
5490
5491
5492
5493
5494
5495
5496 </td>
5497
5498
5499
5500
5501
5502
5503 </tr>
5504
5505
5506
5507
5508
5509
5510
5511    <tr>
5512
5513
5514
5515
5516
5517
5518 <td style="vertical-align: top;"> 
5519     
5520     
5521     
5522     
5523     
5524     
5525      <p><a name="grid_matching"></a><b>grid_matching</b></p>
5526
5527
5528
5529
5530
5531
5532
5533      </td>
5534
5535
5536
5537
5538
5539
5540 <td style="vertical-align: top;">C * 6</td>
5541
5542
5543
5544
5545
5546
5547
5548      <td style="vertical-align: top;"><span style="font-style: italic;">'match'</span></td>
5549
5550
5551
5552
5553
5554
5555 <td style="vertical-align: top;">Variable to adjust the
5556subdomain
5557sizes in parallel runs.<br>
5558
5559
5560
5561
5562
5563
5564 <br>
5565
5566
5567
5568
5569
5570
5571
5572For <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>,
5573the subdomains are forced to have an identical
5574size on all processors. In this case the processor numbers in the
5575respective directions of the virtual processor net must fulfill certain
5576divisor conditions concerning the grid point numbers in the three
5577directions (see <a href="#nx">nx</a>, <a href="#ny">ny</a>
5578and <a href="#nz">nz</a>).
5579Advantage of this method is that all PEs bear the same computational
5580load.<br>
5581
5582
5583
5584
5585
5586
5587 <br>
5588
5589
5590
5591
5592
5593
5594
5595There is no such restriction by default, because then smaller
5596subdomains are allowed on those processors which
5597form the right and/or north boundary of the virtual processor grid. On
5598all other processors the subdomains are of same size. Whether smaller
5599subdomains are actually used, depends on the number of processors and
5600the grid point numbers used. Information about the respective settings
5601are 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>
5602
5603
5604
5605
5606
5607
5608
5609      <br>
5610
5611
5612
5613
5614
5615
5616
5617When 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>)
5618only <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>
5619is allowed.<br>
5620
5621
5622
5623
5624
5625
5626 <br>
5627
5628
5629
5630
5631
5632
5633 <b>Note:</b><br>
5634
5635
5636
5637
5638
5639
5640
5641In some cases for small processor numbers there may be a very bad load
5642balancing among the
5643processors which may reduce the performance of the code.</td>
5644
5645
5646
5647
5648
5649
5650 </tr>
5651
5652
5653
5654
5655
5656
5657
5658    <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
5659switch on the prognostic equation for specific
5660humidity q.<br>
5661
5662
5663
5664
5665
5666
5667 </p>
5668
5669
5670
5671
5672
5673
5674 
5675     
5676     
5677     
5678     
5679     
5680     
5681      <p>The initial vertical
5682profile 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>
5683and <a href="chapter_4.1.html#q_vertical_gradient_level">q_vertical_gradient_level</a>.&nbsp;
5684Boundary conditions can be set via <a href="chapter_4.1.html#q_surface_initial_change">q_surface_initial_change</a>
5685and <a href="chapter_4.1.html#surface_waterflux">surface_waterflux</a>.<br>
5686
5687
5688
5689
5690
5691
5692
5693      </p>
5694
5695
5696
5697
5698
5699
5700
5701If the condensation scheme is switched on (<a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
5702= .TRUE.), q becomes the total liquid water content (sum of specific
5703humidity 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>),
5704this parameter defines the vertical thickness of the turbulent layer up
5705to which the turbulence extracted at the recycling plane (see <a href="chapter_4.1.html#recycling_width">recycling_width</a>)
5706shall be imposed to the inflow. Above this level the turbulence signal
5707is linearly damped to zero. The transition range within which the
5708signal 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>
5709
5710
5711
5712
5713
5714
5715 <td style="vertical-align: top;"><a name="inflow_disturbance_begin"></a><b>inflow_disturbance_<br>
5716
5717
5718
5719
5720
5721
5722
5723begin</b></td>
5724
5725
5726
5727
5728
5729
5730 <td style="vertical-align: top;">I</td>
5731
5732
5733
5734
5735
5736
5737
5738      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(10,</span><br style="font-style: italic;">
5739
5740
5741
5742
5743
5744
5745 <span style="font-style: italic;">nx/2 or ny/2)</span></td>
5746
5747
5748
5749
5750
5751
5752
5753      <td style="vertical-align: top;">Lower
5754limit of the horizontal range for which random perturbations are to be
5755imposed on the horizontal velocity field (gridpoints).<br>
5756
5757
5758
5759
5760
5761
5762 <br>
5763
5764
5765
5766
5767
5768
5769
5770If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5771or <a href="#bc_ns">bc_ns</a>),
5772this parameter gives the gridpoint number (counted horizontally from
5773the inflow)&nbsp; from which on perturbations are imposed on the
5774horizontal velocity field. Perturbations must be switched on with
5775parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5776
5777
5778
5779
5780
5781
5782
5783    </tr>
5784
5785
5786
5787
5788
5789
5790 <tr>
5791
5792
5793
5794
5795
5796
5797 <td style="vertical-align: top;"><a name="inflow_disturbance_end"></a><b>inflow_disturbance_<br>
5798
5799
5800
5801
5802
5803
5804
5805end</b></td>
5806
5807
5808
5809
5810
5811
5812 <td style="vertical-align: top;">I</td>
5813
5814
5815
5816
5817
5818
5819
5820      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(100,</span><br style="font-style: italic;">
5821
5822
5823
5824
5825
5826
5827 <span style="font-style: italic;">3/4*nx or</span><br style="font-style: italic;">
5828
5829
5830
5831
5832
5833
5834 <span style="font-style: italic;">3/4*ny)</span></td>
5835
5836
5837
5838
5839
5840
5841 <td style="vertical-align: top;">Upper
5842limit of the horizontal range for which random perturbations are
5843to be imposed on the horizontal velocity field (gridpoints).<br>
5844
5845
5846
5847
5848
5849
5850 <br>
5851
5852
5853
5854
5855
5856
5857
5858If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5859or <a href="#bc_ns">bc_ns</a>),
5860this parameter gives the gridpoint number (counted horizontally from
5861the inflow)&nbsp; unto which perturbations are imposed on the
5862horizontal
5863velocity field. Perturbations must be switched on with parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5864
5865
5866
5867
5868
5869
5870
5871    </tr>
5872
5873
5874
5875
5876
5877
5878 <tr>
5879
5880
5881
5882
5883
5884
5885 <td style="vertical-align: top;">
5886     
5887     
5888     
5889     
5890     
5891     
5892      <p><a name="initializing_actions"></a><b>initializing_actions</b></p>
5893
5894
5895
5896
5897
5898
5899
5900      </td>
5901
5902
5903
5904
5905
5906
5907 <td style="vertical-align: top;">C * 100</td>
5908
5909
5910
5911
5912
5913
5914
5915      <td style="vertical-align: top;"><br>
5916
5917
5918
5919
5920
5921
5922 </td>
5923
5924
5925
5926
5927
5928
5929 <td style="vertical-align: top;"> 
5930     
5931     
5932     
5933     
5934     
5935     
5936      <p style="font-style: normal;">Initialization actions
5937to be carried out.&nbsp; </p>
5938
5939
5940
5941
5942
5943
5944 
5945     
5946     
5947     
5948     
5949     
5950     
5951      <p style="font-style: normal;">This parameter does not have a
5952default value and therefore must be assigned with each model run. For
5953restart runs <b>initializing_actions</b> = <span style="font-style: italic;">'read_restart_data'</span>
5954must be set. For the initial run of a job chain the following values
5955are allowed:&nbsp; </p>
5956
5957
5958
5959
5960
5961
5962 
5963     
5964     
5965     
5966     
5967     
5968     
5969      <p style="font-style: normal;"><span style="font-style: italic;">'set_constant_profiles'</span>
5970      </p>
5971
5972
5973
5974
5975
5976
5977 
5978     
5979     
5980     
5981     
5982     
5983     
5984      <ul>
5985
5986
5987
5988
5989
5990
5991 
5992       
5993       
5994       
5995       
5996       
5997       
5998        <p>A horizontal wind profile consisting
5999of linear sections (see <a href="#ug_surface">ug_surface</a>,
6000        <a href="#ug_vertical_gradient">ug_vertical_gradient</a>,
6001        <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>
6002and <a href="#vg_surface">vg_surface</a>, <a href="#vg_vertical_gradient">vg_vertical_gradient</a>,
6003        <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
6004respectively) as well as a vertical temperature (humidity) profile
6005consisting of
6006linear sections (see <a href="#pt_surface">pt_surface</a>,
6007        <a href="#pt_vertical_gradient">pt_vertical_gradient</a>,
6008        <a href="#q_surface">q_surface</a>
6009and <a href="#q_vertical_gradient">q_vertical_gradient</a>)
6010are assumed as initial profiles. The subgrid-scale TKE is set to 0 but K<sub>m</sub>
6011and K<sub>h</sub> are set to very small values because
6012otherwise no TKE
6013would be generated.</p>
6014
6015
6016
6017
6018
6019
6020 
6021     
6022     
6023     
6024     
6025     
6026     
6027      </ul>
6028
6029
6030
6031
6032
6033
6034 
6035     
6036     
6037     
6038     
6039     
6040     
6041      <p style="font-style: italic;">'set_1d-model_profiles' </p>
6042
6043
6044
6045
6046
6047
6048
6049     
6050     
6051     
6052     
6053     
6054     
6055      <ul>
6056
6057
6058
6059
6060
6061
6062 
6063       
6064       
6065       
6066       
6067       
6068       
6069        <p>The arrays of the 3d-model are initialized with
6070the
6071(stationary) solution of the 1d-model. These are the variables e, kh,
6072km, u, v and with Prandtl layer switched on rif, us, usws, vsws. The
6073temperature (humidity) profile consisting of linear sections is set as
6074for 'set_constant_profiles' and assumed as constant in time within the
60751d-model. For steering of the 1d-model a set of parameters with suffix
6076"_1d" (e.g. <a href="#end_time_1d">end_time_1d</a>,
6077        <a href="#damp_level_1d">damp_level_1d</a>)
6078is available.</p>
6079
6080
6081
6082
6083
6084
6085 
6086     
6087     
6088     
6089     
6090     
6091     
6092      </ul>
6093
6094
6095
6096
6097
6098
6099 
6100     
6101     
6102     
6103     
6104     
6105     
6106      <p><span style="font-style: italic;">'by_user'</span></p>
6107
6108
6109
6110
6111
6112
6113     
6114     
6115     
6116     
6117     
6118     
6119      <p style="margin-left: 40px;">The initialization of the arrays
6120of the 3d-model is under complete control of the user and has to be
6121done in routine <a href="chapter_3.5.1.html#user_init_3d_model">user_init_3d_model</a>
6122of the user-interface.<span style="font-style: italic;"></span></p>
6123
6124
6125
6126
6127
6128
6129     
6130     
6131     
6132     
6133     
6134     
6135      <p><span style="font-style: italic;">'initialize_vortex'</span>
6136      </p>
6137
6138
6139
6140
6141
6142
6143 
6144     
6145     
6146     
6147     
6148     
6149     
6150      <div style="margin-left: 40px;">The initial
6151velocity field of the
61523d-model corresponds to a
6153Rankine-vortex with vertical axis. This setting may be used to test
6154advection 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>)
6155are necessary. In order not to distort the vortex, an initial
6156horizontal wind profile constant
6157with height is necessary (to be set by <b>initializing_actions</b>
6158= <span style="font-style: italic;">'set_constant_profiles'</span>)
6159and some other conditions have to be met (neutral stratification,
6160diffusion must be
6161switched off, see <a href="#km_constant">km_constant</a>).
6162The center of the vortex is located at jc = (nx+1)/2. It
6163extends from k = 0 to k = nz+1. Its radius is 8 * <a href="#dx">dx</a>
6164and the exponentially decaying part ranges to 32 * <a href="#dx">dx</a>
6165(see init_rankine.f90). </div>
6166
6167
6168
6169
6170
6171
6172 
6173     
6174     
6175     
6176     
6177     
6178     
6179      <p><span style="font-style: italic;">'initialize_ptanom'</span>
6180      </p>
6181
6182
6183
6184
6185
6186
6187 
6188     
6189     
6190     
6191     
6192     
6193     
6194      <ul>
6195
6196
6197
6198
6199
6200
6201 
6202       
6203       
6204       
6205       
6206       
6207       
6208        <p>A 2d-Gauss-like shape disturbance
6209(x,y) is added to the
6210initial temperature field with radius 10.0 * <a href="#dx">dx</a>
6211and center at jc = (nx+1)/2. This may be used for tests of scalar
6212advection schemes
6213(see <a href="#scalar_advec">scalar_advec</a>).
6214Such tests require a horizontal wind profile constant with hight and
6215diffusion
6216switched off (see <span style="font-style: italic;">'initialize_vortex'</span>).
6217Additionally, the buoyancy term
6218must be switched of in the equation of motion&nbsp; for w (this
6219requires the user to comment out the call of <span style="font-family: monospace;">buoyancy</span> in the
6220source code of <span style="font-family: monospace;">prognostic_equations.f90</span>).</p></ul>
6221
6222
6223
6224
6225
6226
6227 
6228     
6229     
6230     
6231     
6232     
6233     
6234      <p style="font-style: italic;">'read_data_for_recycling'</p><p style="font-style: normal; margin-left: 40px;">Here,
62353d-data from a precursor run are read by the initial (main) run. The
6236precursor run is allowed to have a smaller domain along x and y
6237compared with the main run. Also, different numbers of processors can
6238be used for these two runs. Limitations are that the precursor run must
6239use cyclic horizontal boundary conditions and that the subdomains of
6240the main run must not be larger than the subdomains of the precursor
6241run. If the total domain of the main run is larger than that of the precursor
6242run, the domain is filled by cyclic repetition&nbsp;of the (cyclic)
6243precursor data. This initialization method is recommended if a
6244turbulent 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
6245combined, e.g. <b>initializing_actions</b> = <span style="font-style: italic;">'set_constant_profiles
6246initialize_vortex'</span>, but the values of <span style="font-style: italic;">'set_constant_profiles'</span>,
6247      <span style="font-style: italic;">'set_1d-model_profiles'</span>
6248, and <span style="font-style: italic;">'by_user'</span>
6249must not be given at the same time.</p>
6250
6251
6252
6253
6254
6255
6256 
6257     
6258     
6259     
6260     
6261     
6262     
6263     
6264
6265
6266
6267
6268
6269
6270 </td>
6271
6272
6273
6274
6275
6276
6277 </tr>
6278
6279
6280
6281
6282
6283
6284
6285    <tr>
6286
6287
6288
6289
6290
6291
6292 <td style="vertical-align: top;"> 
6293     
6294     
6295     
6296     
6297     
6298     
6299      <p><a name="km_constant"></a><b>km_constant</b></p>
6300
6301
6302
6303
6304
6305
6306
6307      </td>
6308
6309
6310
6311
6312
6313
6314 <td style="vertical-align: top;">R</td>
6315
6316
6317
6318
6319
6320
6321
6322      <td style="vertical-align: top;"><i>variable<br>
6323
6324
6325
6326
6327
6328
6329
6330(computed from TKE)</i></td>
6331
6332
6333
6334
6335
6336
6337 <td style="vertical-align: top;"> 
6338     
6339     
6340     
6341     
6342     
6343     
6344      <p>Constant eddy
6345diffusivities are used (laminar
6346simulations).&nbsp; </p>
6347
6348
6349
6350
6351
6352
6353 
6354     
6355     
6356     
6357     
6358     
6359     
6360      <p>If this parameter is
6361specified, both in the 1d and in the
63623d-model constant values for the eddy diffusivities are used in
6363space and time with K<sub>m</sub> = <b>km_constant</b>
6364and K<sub>h</sub> = K<sub>m</sub> / <a href="chapter_4.2.html#prandtl_number">prandtl_number</a>.
6365The prognostic equation for the subgrid-scale TKE is switched off.
6366Constant eddy diffusivities are only allowed with the Prandtl layer (<a href="#prandtl_layer">prandtl_layer</a>)
6367switched off.</p>
6368
6369
6370
6371
6372
6373
6374 </td>
6375
6376
6377
6378
6379
6380
6381 </tr>
6382
6383
6384
6385
6386
6387
6388 <tr>
6389
6390
6391
6392
6393
6394
6395 <td style="vertical-align: top;"> 
6396     
6397     
6398     
6399     
6400     
6401     
6402      <p><a name="km_damp_max"></a><b>km_damp_max</b></p>
6403
6404
6405
6406
6407
6408
6409
6410      </td>
6411
6412
6413
6414
6415
6416
6417 <td style="vertical-align: top;">R</td>
6418
6419
6420
6421
6422
6423
6424
6425      <td style="vertical-align: top;"><span style="font-style: italic;">0.5*(dx
6426or dy)</span></td>
6427
6428
6429
6430
6431
6432
6433 <td style="vertical-align: top;">Maximum
6434diffusivity used for filtering the velocity field in the vicinity of
6435the outflow (in m<sup>2</sup>/s).<br>
6436
6437
6438
6439
6440
6441
6442 <br>
6443
6444
6445
6446
6447
6448
6449
6450When using non-cyclic lateral boundaries (see <a href="#bc_lr">bc_lr</a>
6451or <a href="#bc_ns">bc_ns</a>),
6452a smoothing has to be applied to the
6453velocity field in the vicinity of the outflow in order to suppress any
6454reflections of outgoing disturbances. Smoothing is done by increasing
6455the eddy diffusivity along the horizontal direction which is
6456perpendicular to the outflow boundary. Only velocity components
6457parallel to the outflow boundary are filtered (e.g. v and w, if the
6458outflow is along x). Damping is applied from the bottom to the top of
6459the domain.<br>
6460
6461
6462
6463
6464
6465
6466 <br>
6467
6468
6469
6470
6471
6472
6473
6474The horizontal range of the smoothing is controlled by <a href="#outflow_damping_width">outflow_damping_width</a>
6475which defines the number of gridpoints (counted from the outflow
6476boundary) from where on the smoothing is applied. Starting from that
6477point, the eddy diffusivity is linearly increased (from zero to its
6478maximum value given by <span style="font-weight: bold;">km_damp_max</span>)
6479until half of the damping range width, from where it remains constant
6480up to the outflow boundary. If at a certain grid point the eddy
6481diffusivity calculated from the flow field is larger than as described
6482above, it is used instead.<br>
6483
6484
6485
6486
6487
6488
6489 <br>
6490
6491
6492
6493
6494
6495
6496
6497The default value of <span style="font-weight: bold;">km_damp_max</span>
6498has been empirically proven to be sufficient.</td>
6499
6500
6501
6502
6503
6504
6505 </tr>
6506
6507
6508
6509
6510
6511
6512 <tr>
6513
6514      <td style="vertical-align: top;"><a name="lad_surface"></a><span style="font-weight: bold;">lad_surface</span></td>
6515
6516      <td style="vertical-align: top;">R</td>
6517
6518      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
6519
6520      <td style="vertical-align: top;">Surface value of the leaf area density (in m<sup>2</sup>/m<sup>3</sup>).<br>
6521
6522      <br>
6523
6524This
6525parameter 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,
6526the leaf area density profile is constructed with <a href="#lad_vertical_gradient">lad_vertical_gradient</a>
6527and <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level
6528      </a>.</td>
6529
6530    </tr>
6531
6532    <tr>
6533
6534      <td style="vertical-align: top;"><a name="lad_vertical_gradient"></a><span style="font-weight: bold;">lad_vertical_gradient</span></td>
6535
6536      <td style="vertical-align: top;">R (10)</td>
6537
6538      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6539
6540      <td style="vertical-align: top;">Gradient(s) of the leaf area density (in&nbsp;m<sup>2</sup>/m<sup>4</sup>).<br>
6541
6542      <br>
6543
6544     
6545      <p>This leaf area density gradient
6546holds starting from the height&nbsp;
6547level defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6548(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>)
6549up 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
6550if <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>(1)
6551= <i>0.0</i>) can be assigned. The leaf area density at the surface is
6552assigned via <a href="#lad_surface">lad_surface</a>.&nbsp;
6553      </p>
6554
6555      </td>
6556
6557    </tr>
6558
6559    <tr>
6560
6561      <td style="vertical-align: top;"><a name="lad_vertical_gradient_level"></a><span style="font-weight: bold;">lad_vertical_gradient_level</span></td>
6562
6563      <td style="vertical-align: top;">R (10)</td>
6564
6565      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6566
6567      <td style="vertical-align: top;">Height level from which on the&nbsp;gradient
6568of the leaf area density defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6569is effective (in m).<br>
6570
6571      <br>
6572
6573The height levels have to be assigned in ascending order. The
6574default 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>
6575
6576    </tr>
6577
6578    <tr>
6579
6580      <td style="vertical-align: top;"><a name="leaf_surface_concentration"></a><b>leaf_surface_concentration</b></td>
6581
6582      <td style="vertical-align: top;">R</td>
6583
6584      <td style="vertical-align: top;"><i>0.0</i></td>
6585
6586      <td style="vertical-align: top;">Concentration of a passive scalar at the surface of a leaf (in K m/s).<br>
6587
6588
6589      <br>
6590
6591
6592This 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>.
6593The value of the concentration of a passive scalar at the surface of a
6594leaf is required for the parametrisation of the sources and sinks of
6595scalar concentration due to the canopy.</td>
6596
6597    </tr>
6598
6599    <tr>
6600
6601
6602
6603
6604
6605
6606
6607      <td style="vertical-align: top;"> 
6608     
6609     
6610     
6611     
6612     
6613     
6614      <p><a name="long_filter_factor"></a><b>long_filter_factor</b></p>
6615
6616
6617
6618
6619
6620
6621
6622      </td>
6623
6624
6625
6626
6627
6628
6629 <td style="vertical-align: top;">R</td>
6630
6631
6632
6633
6634
6635
6636
6637      <td style="vertical-align: top;"><i>0.0</i></td>
6638
6639
6640
6641
6642
6643
6644
6645      <td style="vertical-align: top;"> 
6646     
6647     
6648     
6649     
6650     
6651     
6652      <p>Filter factor
6653for the so-called Long-filter.<br>
6654
6655
6656
6657
6658
6659
6660 </p>
6661
6662
6663
6664
6665
6666
6667 
6668     
6669     
6670     
6671     
6672     
6673     
6674      <p><br>
6675
6676
6677
6678
6679
6680
6681
6682This filter very efficiently
6683eliminates 2-delta-waves sometimes cauesed by the upstream-spline
6684scheme (see Mahrer and
6685Pielke, 1978: Mon. Wea. Rev., 106, 818-830). It works in all three
6686directions in space. A value of <b>long_filter_factor</b>
6687= <i>0.01</i>
6688sufficiently removes the small-scale waves without affecting the
6689longer waves.<br>
6690
6691
6692
6693
6694
6695
6696 </p>
6697
6698
6699
6700
6701
6702
6703 
6704     
6705     
6706     
6707     
6708     
6709     
6710      <p>By default, the filter is
6711switched off (= <i>0.0</i>).
6712It is exclusively applied to the tendencies calculated by the
6713upstream-spline scheme (see <a href="#momentum_advec">momentum_advec</a>
6714and <a href="#scalar_advec">scalar_advec</a>),
6715not to the prognostic variables themselves. At the bottom and top
6716boundary of the model domain the filter effect for vertical
67172-delta-waves is reduced. There, the amplitude of these waves is only
6718reduced by approx. 50%, otherwise by nearly 100%.&nbsp; <br>
6719
6720
6721
6722
6723
6724
6725
6726Filter factors with values &gt; <i>0.01</i> also
6727reduce the amplitudes
6728of waves with wavelengths longer than 2-delta (see the paper by Mahrer
6729and
6730Pielke, quoted above). </p>
6731
6732
6733
6734
6735
6736
6737 </td>
6738
6739
6740
6741
6742
6743
6744 </tr>
6745
6746
6747
6748
6749
6750
6751 <tr>
6752
6753
6754
6755
6756
6757
6758      <td style="vertical-align: top;"><a name="loop_optimization"></a><span style="font-weight: bold;">loop_optimization</span></td>
6759
6760
6761
6762
6763
6764
6765      <td style="vertical-align: top;">C*16</td>
6766
6767
6768
6769
6770
6771
6772      <td style="vertical-align: top;"><span style="font-style: italic;">see right</span></td>
6773
6774
6775
6776
6777
6778
6779      <td>Method used to optimize loops for solving the prognostic equations .<br>
6780
6781
6782
6783
6784
6785
6786      <br>
6787
6788
6789
6790
6791
6792
6793By
6794default, the optimization method depends on the host on which PALM is
6795running. On machines with vector-type CPUs, single 3d-loops are used to
6796calculate each tendency term of each prognostic equation, while on all
6797other machines, all prognostic equations are solved within one big loop
6798over 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>
6799
6800
6801
6802
6803
6804
6805      <br>
6806
6807
6808
6809
6810
6811
6812The 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>
6813
6814
6815
6816
6817
6818
6819    </tr>
6820
6821
6822
6823
6824
6825
6826    <tr>
6827
6828
6829
6830
6831
6832
6833
6834      <td style="vertical-align: top;"><a name="mixing_length_1d"></a><span style="font-weight: bold;">mixing_length_1d</span><br>
6835
6836
6837
6838
6839
6840
6841
6842      </td>
6843
6844
6845
6846
6847
6848
6849 <td style="vertical-align: top;">C*20<br>
6850
6851
6852
6853
6854
6855
6856
6857      </td>
6858
6859
6860
6861
6862
6863
6864 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
6865
6866
6867
6868
6869
6870
6871 <span style="font-style: italic;">model'</span><br>
6872
6873
6874
6875
6876
6877
6878 </td>
6879
6880
6881
6882
6883
6884
6885
6886      <td style="vertical-align: top;">Mixing length used in the
68871d-model.<br>
6888
6889
6890
6891
6892
6893
6894 <br>
6895
6896
6897
6898
6899
6900
6901
6902By default the mixing length is calculated as in the 3d-model (i.e. it
6903depends on the grid spacing).<br>
6904
6905
6906
6907
6908
6909
6910 <br>
6911
6912
6913
6914
6915
6916
6917
6918By setting <span style="font-weight: bold;">mixing_length_1d</span>
6919= <span style="font-style: italic;">'blackadar'</span>,
6920the so-called Blackadar mixing length is used (l = kappa * z / ( 1 +
6921kappa * z / lambda ) with the limiting value lambda = 2.7E-4 * u_g / f).<br>
6922
6923
6924
6925
6926
6927
6928
6929      </td>
6930
6931
6932
6933
6934
6935
6936 </tr>
6937
6938
6939
6940
6941
6942
6943 
6944
6945
6946
6947
6948
6949
6950
6951    <tr>
6952
6953
6954
6955
6956
6957
6958 <td style="vertical-align: top;"> 
6959     
6960     
6961     
6962     
6963     
6964     
6965      <p><a name="momentum_advec"></a><b>momentum_advec</b></p>
6966
6967
6968
6969
6970
6971
6972
6973      </td>
6974
6975
6976
6977
6978
6979
6980 <td style="vertical-align: top;">C * 10</td>
6981
6982
6983
6984
6985
6986
6987
6988      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
6989
6990
6991
6992
6993
6994
6995
6996      <td style="vertical-align: top;"> 
6997     
6998     
6999     
7000     
7001     
7002     
7003      <p>Advection
7004scheme to be used for the momentum equations.<br>
7005
7006
7007
7008
7009
7010
7011 <br>
7012
7013
7014
7015
7016
7017
7018
7019The user can choose between the following schemes:<br>
7020
7021
7022
7023
7024
7025
7026
7027&nbsp;<br>
7028
7029
7030
7031
7032
7033
7034 <br>
7035
7036
7037
7038
7039
7040
7041 <span style="font-style: italic;">'pw-scheme'</span><br>
7042
7043
7044
7045
7046
7047
7048
7049      </p>
7050
7051
7052
7053
7054
7055
7056 
7057     
7058     
7059     
7060     
7061     
7062     
7063      <div style="margin-left: 40px;">The scheme of
7064Piascek and
7065Williams (1970, J. Comp. Phys., 6,
7066392-405) with central differences in the form C3 is used.<br>
7067
7068
7069
7070
7071
7072
7073
7074If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
7075= <span style="font-style: italic;">'leapfrog+euler'</span>
7076the
7077advection scheme is - for the Euler-timestep - automatically switched
7078to an upstream-scheme.<br>
7079
7080
7081
7082
7083
7084
7085 </div>
7086
7087
7088
7089
7090
7091
7092 
7093     
7094     
7095     
7096     
7097     
7098     
7099      <p> </p>
7100
7101
7102
7103
7104
7105
7106 
7107     
7108     
7109     
7110     
7111     
7112     
7113      <p><span style="font-style: italic;">'ups-scheme'</span><br>
7114
7115
7116
7117
7118
7119
7120
7121      </p>
7122
7123
7124
7125
7126
7127
7128 
7129     
7130     
7131     
7132     
7133     
7134     
7135      <div style="margin-left: 40px;">The
7136upstream-spline scheme is
7137used
7138(see Mahrer and Pielke,
71391978: Mon. Wea. Rev., 106, 818-830). In opposite to the
7140Piascek-Williams scheme, this is characterized by much better numerical
7141features (less numerical diffusion, better preservation of flow
7142structures, e.g. vortices), but computationally it is much more
7143expensive. In
7144addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
7145= <span style="font-style: italic;">'</span><i>euler'</i>),
7146i.e. the
7147timestep accuracy is only of first order.
7148For this reason the advection of scalar variables (see <a href="#scalar_advec">scalar_advec</a>)
7149should then also be carried out with the upstream-spline scheme,
7150because otherwise the scalar variables would
7151be subject to large numerical diffusion due to the upstream
7152scheme.&nbsp; </div>
7153
7154
7155
7156
7157
7158
7159 
7160     
7161     
7162     
7163     
7164     
7165     
7166      <p style="margin-left: 40px;">Since
7167the cubic splines used tend
7168to overshoot under
7169certain circumstances, this effect must be adjusted by suitable
7170filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
7171      <a href="#long_filter_factor">long_filter_factor</a>,
7172      <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>).
7173This is always neccessary for runs with stable stratification,
7174even if this stratification appears only in parts of the model domain.<br>
7175
7176
7177
7178
7179
7180
7181
7182      </p>
7183
7184
7185
7186
7187
7188
7189 
7190     
7191     
7192     
7193     
7194     
7195     
7196      <div style="margin-left: 40px;">With stable
7197stratification the
7198upstream-spline scheme also
7199produces gravity waves with large amplitude, which must be
7200suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
7201
7202
7203
7204
7205
7206
7207
7208      <br>
7209
7210
7211
7212
7213
7214
7215 <span style="font-weight: bold;">Important: </span>The&nbsp;
7216upstream-spline scheme is not implemented for humidity and passive
7217scalars (see&nbsp;<a href="#humidity">humidity</a>
7218and <a href="#passive_scalar">passive_scalar</a>)
7219and requires the use of a 2d-domain-decomposition. The last conditions
7220severely restricts code optimization on several machines leading to
7221very long execution times! The scheme is also not allowed for
7222non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
7223and <a href="#bc_ns">bc_ns</a>).</div>
7224
7225
7226
7227
7228
7229
7230 </td>
7231
7232
7233
7234
7235
7236
7237
7238    </tr>
7239
7240
7241
7242
7243
7244
7245 <tr>
7246
7247
7248
7249
7250
7251
7252 <td style="vertical-align: top;"><a name="netcdf_precision"></a><span style="font-weight: bold;">netcdf_precision</span><br>
7253
7254
7255
7256
7257
7258
7259
7260      </td>
7261
7262
7263
7264
7265
7266
7267 <td style="vertical-align: top;">C*20<br>
7268
7269
7270
7271
7272
7273
7274
7275(10)<br>
7276
7277
7278
7279
7280
7281
7282 </td>
7283
7284
7285
7286
7287
7288
7289 <td style="vertical-align: top;"><span style="font-style: italic;">single preci-</span><br style="font-style: italic;">
7290
7291
7292
7293
7294
7295
7296 <span style="font-style: italic;">sion for all</span><br style="font-style: italic;">
7297
7298
7299
7300
7301
7302
7303 <span style="font-style: italic;">output quan-</span><br style="font-style: italic;">
7304
7305
7306
7307
7308
7309
7310 <span style="font-style: italic;">tities</span><br>
7311
7312
7313
7314
7315
7316
7317 </td>
7318
7319
7320
7321
7322
7323
7324
7325      <td style="vertical-align: top;">Defines the accuracy of
7326the NetCDF output.<br>
7327
7328
7329
7330
7331
7332
7333 <br>
7334
7335
7336
7337
7338
7339
7340
7341By default, all NetCDF output data (see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
7342have single precision&nbsp; (4 byte) accuracy. Double precision (8
7343byte) can be choosen alternatively.<br>
7344
7345
7346
7347
7348
7349
7350
7351Accuracy for the different output data (cross sections, 3d-volume data,
7352spectra, etc.) can be set independently.<br>
7353
7354
7355
7356
7357
7358
7359 <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL4'</span>
7360(single precision) or <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL8'</span>
7361(double precision) are the two principally allowed values for <span style="font-weight: bold;">netcdf_precision</span>,
7362where the string <span style="font-style: italic;">'&lt;out&gt;'
7363      </span>can be chosen out of the following list:<br>
7364
7365
7366
7367
7368
7369
7370 <br>
7371
7372
7373
7374
7375
7376
7377
7378     
7379     
7380     
7381     
7382     
7383     
7384      <table style="text-align: left; width: 284px; height: 234px;" border="1" cellpadding="2" cellspacing="2">
7385
7386
7387
7388
7389
7390
7391 <tbody>
7392
7393
7394
7395
7396
7397
7398
7399          <tr>
7400
7401
7402
7403
7404
7405
7406 <td style="vertical-align: top;"><span style="font-style: italic;">'xy'</span><br>
7407
7408
7409
7410
7411
7412
7413 </td>
7414
7415
7416
7417
7418
7419
7420
7421            <td style="vertical-align: top;">horizontal cross section<br>
7422
7423
7424
7425
7426
7427
7428
7429            </td>
7430
7431
7432
7433
7434
7435
7436 </tr>
7437
7438
7439
7440
7441
7442
7443 <tr>
7444
7445
7446
7447
7448
7449
7450 <td style="vertical-align: top;"><span style="font-style: italic;">'xz'</span><br>
7451
7452
7453
7454
7455
7456
7457 </td>
7458
7459
7460
7461
7462
7463
7464
7465            <td style="vertical-align: top;">vertical (xz) cross
7466section<br>
7467
7468
7469
7470
7471
7472
7473 </td>
7474
7475
7476
7477
7478
7479
7480 </tr>
7481
7482
7483
7484
7485
7486
7487 <tr>
7488
7489
7490
7491
7492
7493
7494 <td style="vertical-align: top;"><span style="font-style: italic;">'yz'</span><br>
7495
7496
7497
7498
7499
7500
7501 </td>
7502
7503
7504
7505
7506
7507
7508
7509            <td style="vertical-align: top;">vertical (yz) cross
7510section<br>
7511
7512
7513
7514
7515
7516
7517 </td>
7518
7519
7520
7521
7522
7523
7524 </tr>
7525
7526
7527
7528
7529
7530
7531 <tr>
7532
7533
7534
7535
7536
7537
7538 <td style="vertical-align: top;"><span style="font-style: italic;">'2d'</span><br>
7539
7540
7541
7542
7543
7544
7545 </td>
7546
7547
7548
7549
7550
7551
7552
7553            <td style="vertical-align: top;">all cross sections<br>
7554
7555
7556
7557
7558
7559
7560
7561            </td>
7562
7563
7564
7565
7566
7567
7568 </tr>
7569
7570
7571
7572
7573
7574
7575 <tr>
7576
7577
7578
7579
7580
7581
7582 <td style="vertical-align: top;"><span style="font-style: italic;">'3d'</span><br>
7583
7584
7585
7586
7587
7588
7589 </td>
7590
7591
7592
7593
7594
7595
7596
7597            <td style="vertical-align: top;">volume data<br>
7598
7599
7600
7601
7602
7603
7604 </td>
7605
7606
7607
7608
7609
7610
7611
7612          </tr>
7613
7614
7615
7616
7617
7618
7619 <tr>
7620
7621
7622
7623
7624
7625
7626 <td style="vertical-align: top;"><span style="font-style: italic;">'pr'</span><br>
7627
7628
7629
7630
7631
7632
7633 </td>
7634
7635
7636
7637
7638
7639
7640
7641            <td style="vertical-align: top;">vertical profiles<br>
7642
7643
7644
7645
7646
7647
7648
7649            </td>
7650
7651
7652
7653
7654
7655
7656 </tr>
7657
7658
7659
7660
7661
7662
7663 <tr>
7664
7665
7666
7667
7668
7669
7670 <td style="vertical-align: top;"><span style="font-style: italic;">'ts'</span><br>
7671
7672
7673
7674
7675
7676
7677 </td>
7678
7679
7680
7681
7682
7683
7684
7685            <td style="vertical-align: top;">time series, particle
7686time series<br>
7687
7688
7689
7690
7691
7692
7693 </td>
7694
7695
7696
7697
7698
7699
7700 </tr>
7701
7702
7703
7704
7705
7706
7707 <tr>
7708
7709
7710
7711
7712
7713
7714 <td style="vertical-align: top;"><span style="font-style: italic;">'sp'</span><br>
7715
7716
7717
7718
7719
7720
7721 </td>
7722
7723
7724
7725
7726
7727
7728
7729            <td style="vertical-align: top;">spectra<br>
7730
7731
7732
7733
7734
7735
7736 </td>
7737
7738
7739
7740
7741
7742
7743
7744          </tr>
7745
7746
7747
7748
7749
7750
7751 <tr>
7752
7753
7754
7755
7756
7757
7758 <td style="vertical-align: top;"><span style="font-style: italic;">'prt'</span><br>
7759
7760
7761
7762
7763
7764
7765 </td>
7766
7767
7768
7769
7770
7771
7772
7773            <td style="vertical-align: top;">particles<br>
7774
7775
7776
7777
7778
7779
7780 </td>
7781
7782
7783
7784
7785
7786
7787
7788          </tr>
7789
7790
7791
7792
7793
7794
7795 <tr>
7796
7797
7798
7799
7800
7801
7802 <td style="vertical-align: top;"><span style="font-style: italic;">'all'</span><br>
7803
7804
7805
7806
7807
7808
7809 </td>
7810
7811
7812
7813
7814
7815
7816
7817            <td style="vertical-align: top;">all output quantities<br>
7818
7819
7820
7821
7822
7823
7824
7825            </td>
7826
7827
7828
7829
7830
7831
7832 </tr>
7833
7834
7835
7836
7837
7838
7839 
7840       
7841       
7842       
7843       
7844       
7845       
7846        </tbody> 
7847     
7848     
7849     
7850     
7851     
7852     
7853      </table>
7854
7855
7856
7857
7858
7859
7860 <br>
7861
7862
7863
7864
7865
7866
7867 <span style="font-weight: bold;">Example:</span><br>
7868
7869
7870
7871
7872
7873
7874
7875If all cross section data and the particle data shall be output in
7876double 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>
7877has to be assigned.<br>
7878
7879
7880
7881
7882
7883
7884 </td>
7885
7886
7887
7888
7889
7890
7891 </tr>
7892
7893
7894
7895
7896
7897
7898
7899   
7900
7901
7902
7903
7904
7905
7906 
7907
7908
7909
7910
7911
7912
7913
7914    <tr>
7915
7916
7917
7918
7919
7920
7921 <td style="vertical-align: top;"> 
7922     
7923     
7924     
7925     
7926     
7927     
7928      <p><a name="nsor_ini"></a><b>nsor_ini</b></p>
7929
7930
7931
7932
7933
7934
7935
7936      </td>
7937
7938
7939
7940
7941
7942
7943 <td style="vertical-align: top;">I</td>
7944
7945
7946
7947
7948
7949
7950
7951      <td style="vertical-align: top;"><i>100</i></td>
7952
7953
7954
7955
7956
7957
7958
7959      <td style="vertical-align: top;"> 
7960     
7961     
7962     
7963     
7964     
7965     
7966      <p>Initial number
7967of iterations with the SOR algorithm.&nbsp; </p>
7968
7969
7970
7971
7972
7973
7974 
7975     
7976     
7977     
7978     
7979     
7980     
7981      <p>This
7982parameter is only effective if the SOR algorithm was
7983selected as the pressure solver scheme (<a href="chapter_4.2.html#psolver">psolver</a>
7984= <span style="font-style: italic;">'sor'</span>)
7985and specifies the
7986number of initial iterations of the SOR
7987scheme (at t = 0). The number of subsequent iterations at the following
7988timesteps is determined
7989with the parameter <a href="#nsor">nsor</a>.
7990Usually <b>nsor</b> &lt; <b>nsor_ini</b>,
7991since in each case
7992subsequent calls to <a href="chapter_4.2.html#psolver">psolver</a>
7993use the solution of the previous call as initial value. Suitable
7994test runs should determine whether sufficient convergence of the
7995solution is obtained with the default value and if necessary the value
7996of <b>nsor_ini</b> should be changed.</p>
7997
7998
7999
8000
8001
8002
8003 </td>
8004
8005
8006
8007
8008
8009
8010
8011    </tr>
8012
8013
8014
8015
8016
8017
8018 <tr>
8019
8020
8021
8022
8023
8024
8025 <td style="vertical-align: top;">
8026     
8027     
8028     
8029     
8030     
8031     
8032      <p><a name="nx"></a><b>nx</b></p>
8033
8034
8035
8036
8037
8038
8039
8040      </td>
8041
8042
8043
8044
8045
8046
8047 <td style="vertical-align: top;">I</td>
8048
8049
8050
8051
8052
8053
8054
8055      <td style="vertical-align: top;"><br>
8056
8057
8058
8059
8060
8061
8062 </td>
8063
8064
8065
8066
8067
8068
8069 <td style="vertical-align: top;"> 
8070     
8071     
8072     
8073     
8074     
8075     
8076      <p>Number of grid
8077points in x-direction.&nbsp; </p>
8078
8079
8080
8081
8082
8083
8084 
8085     
8086     
8087     
8088     
8089     
8090     
8091      <p>A value for this
8092parameter must be assigned. Since the lower
8093array bound in PALM
8094starts with i = 0, the actual number of grid points is equal to <b>nx+1</b>.
8095In case of cyclic boundary conditions along x, the domain size is (<b>nx+1</b>)*
8096      <a href="#dx">dx</a>.</p>
8097
8098
8099
8100
8101
8102
8103 
8104     
8105     
8106     
8107     
8108     
8109     
8110      <p>For
8111parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8112= <span style="font-style: italic;">'strict'</span>,
8113      <b>nx+1</b> must
8114be an integral multiple
8115of the processor numbers (see <a href="#npex">npex</a>
8116and <a href="#npey">npey</a>)
8117along x- as well as along y-direction (due to data
8118transposition restrictions).</p>
8119
8120
8121
8122
8123
8124
8125     
8126     
8127     
8128     
8129     
8130     
8131      <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>
8132and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8133
8134
8135
8136
8137
8138
8139 </td>
8140
8141
8142
8143
8144
8145
8146 </tr>
8147
8148
8149
8150
8151
8152
8153 <tr>
8154
8155
8156
8157
8158
8159
8160
8161      <td style="vertical-align: top;"> 
8162     
8163     
8164     
8165     
8166     
8167     
8168      <p><a name="ny"></a><b>ny</b></p>
8169
8170
8171
8172
8173
8174
8175
8176      </td>
8177
8178
8179
8180
8181
8182
8183 <td style="vertical-align: top;">I</td>
8184
8185
8186
8187
8188
8189
8190
8191      <td style="vertical-align: top;"><br>
8192
8193
8194
8195
8196
8197
8198 </td>
8199
8200
8201
8202
8203
8204
8205 <td style="vertical-align: top;"> 
8206     
8207     
8208     
8209     
8210     
8211     
8212      <p>Number of grid
8213points in y-direction.&nbsp; </p>
8214
8215
8216
8217
8218
8219
8220 
8221     
8222     
8223     
8224     
8225     
8226     
8227      <p>A value for this
8228parameter must be assigned. Since the lower
8229array bound in PALM starts with j = 0, the actual number of grid points
8230is equal to <b>ny+1</b>. In case of cyclic boundary
8231conditions along
8232y, the domain size is (<b>ny+1</b>) * <a href="#dy">dy</a>.</p>
8233
8234
8235
8236
8237
8238
8239
8240     
8241     
8242     
8243     
8244     
8245     
8246      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8247= <span style="font-style: italic;">'strict'</span>,
8248      <b>ny+1</b> must
8249be an integral multiple
8250of the processor numbers (see <a href="#npex">npex</a>
8251and <a href="#npey">npey</a>)&nbsp;
8252along y- as well as along x-direction (due to data
8253transposition restrictions).</p>
8254
8255
8256
8257
8258
8259
8260     
8261     
8262     
8263     
8264     
8265     
8266      <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>
8267and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8268
8269
8270
8271
8272
8273
8274 </td>
8275
8276
8277
8278
8279
8280
8281 </tr>
8282
8283
8284
8285
8286
8287
8288 <tr>
8289
8290
8291
8292
8293
8294
8295
8296      <td style="vertical-align: top;"> 
8297     
8298     
8299     
8300     
8301     
8302     
8303      <p><a name="nz"></a><b>nz</b></p>
8304
8305
8306
8307
8308
8309
8310
8311      </td>
8312
8313
8314
8315
8316
8317
8318 <td style="vertical-align: top;">I</td>
8319
8320
8321
8322
8323
8324
8325
8326      <td style="vertical-align: top;"><br>
8327
8328
8329
8330
8331
8332
8333 </td>
8334
8335
8336
8337
8338
8339
8340 <td style="vertical-align: top;"> 
8341     
8342     
8343     
8344     
8345     
8346     
8347      <p>Number of grid
8348points in z-direction.&nbsp; </p>
8349
8350
8351
8352
8353
8354
8355 
8356     
8357     
8358     
8359     
8360     
8361     
8362      <p>A value for this
8363parameter must be assigned. Since the lower
8364array bound in PALM
8365starts with k = 0 and since one additional grid point is added at the
8366top boundary (k = <b>nz+1</b>), the actual number of grid
8367points is <b>nz+2</b>.
8368However, the prognostic equations are only solved up to <b>nz</b>
8369(u,
8370v)
8371or up to <b>nz-1</b> (w, scalar quantities). The top
8372boundary for u
8373and v is at k = <b>nz+1</b> (u, v) while at k = <b>nz</b>
8374for all
8375other quantities.&nbsp; </p>
8376
8377
8378
8379
8380
8381
8382 
8383     
8384     
8385     
8386     
8387     
8388     
8389      <p>For parallel
8390runs,&nbsp; in case of <a href="#grid_matching">grid_matching</a>
8391= <span style="font-style: italic;">'strict'</span>,
8392      <b>nz</b> must
8393be an integral multiple of
8394the number of processors in x-direction (due to data transposition
8395restrictions).</p>
8396
8397
8398
8399
8400
8401
8402 </td>
8403
8404
8405
8406
8407
8408
8409 </tr>
8410
8411
8412
8413
8414
8415
8416 <tr>
8417
8418
8419
8420
8421
8422
8423      <td style="vertical-align: top;"><a name="ocean"></a><span style="font-weight: bold;">ocean</span></td>
8424
8425
8426
8427
8428
8429
8430      <td style="vertical-align: top;">L</td>
8431
8432
8433
8434
8435
8436
8437      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
8438
8439
8440
8441
8442
8443
8444      <td style="vertical-align: top;">Parameter to switch on&nbsp;ocean runs.<br>
8445
8446
8447
8448
8449
8450
8451      <br>
8452
8453
8454
8455
8456
8457
8458By 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>
8459
8460
8461
8462
8463
8464
8465      <br>
8466
8467
8468
8469
8470
8471
8472     
8473     
8474     
8475     
8476     
8477     
8478      <ul>
8479
8480
8481
8482
8483
8484
8485        <li>An additional prognostic equation for salinity is solved.</li>
8486
8487
8488
8489
8490
8491
8492        <li>Potential temperature in buoyancy and stability-related terms is replaced by potential density.</li>
8493
8494
8495
8496
8497
8498
8499        <li>Potential
8500density is calculated from the equation of state for seawater after
8501each timestep, using the algorithm proposed by Jackett et al. (2006, J.
8502Atmos. Oceanic Technol., <span style="font-weight: bold;">23</span>, 1709-1728).<br>
8503
8504
8505
8506
8507
8508
8509So far, only the initial hydrostatic pressure is entered into this equation.</li>
8510
8511
8512
8513
8514
8515
8516        <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>
8517
8518
8519
8520
8521
8522
8523        <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>
8524
8525
8526
8527
8528
8529
8530        <li>Zero salinity flux is used as default boundary condition at the bottom of the sea.</li>
8531
8532
8533
8534
8535
8536
8537        <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>
8538
8539
8540
8541
8542
8543
8544     
8545     
8546     
8547     
8548     
8549     
8550      </ul>
8551
8552
8553
8554
8555
8556
8557      <br>
8558
8559
8560
8561
8562
8563
8564Relevant 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>
8565
8566
8567
8568
8569
8570
8571      <br>
8572
8573
8574
8575
8576
8577
8578Section <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>
8579
8580
8581
8582
8583
8584
8585      <br>
8586
8587
8588
8589
8590
8591
8592      <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>
8593
8594
8595
8596      </td>
8597
8598
8599
8600
8601
8602
8603    </tr>
8604
8605
8606
8607
8608
8609
8610    <tr>
8611
8612
8613
8614
8615
8616
8617 <td style="vertical-align: top;"> 
8618     
8619     
8620     
8621     
8622     
8623     
8624      <p><a name="omega"></a><b>omega</b></p>
8625
8626
8627
8628
8629
8630
8631
8632      </td>
8633
8634
8635
8636
8637
8638
8639 <td style="vertical-align: top;">R</td>
8640
8641
8642
8643
8644
8645
8646
8647      <td style="vertical-align: top;"><i>7.29212E-5</i></td>
8648
8649
8650
8651
8652
8653
8654
8655      <td style="vertical-align: top;"> 
8656     
8657     
8658     
8659     
8660     
8661     
8662      <p>Angular
8663velocity of the rotating system (in rad s<sup>-1</sup>).&nbsp;
8664      </p>
8665
8666
8667
8668
8669
8670
8671 
8672     
8673     
8674     
8675     
8676     
8677     
8678      <p>The angular velocity of the earth is set by
8679default. The
8680values
8681of the Coriolis parameters are calculated as:&nbsp; </p>
8682
8683
8684
8685
8686
8687
8688 
8689     
8690     
8691     
8692     
8693     
8694     
8695      <ul>
8696
8697
8698
8699
8700
8701
8702
8703       
8704       
8705       
8706       
8707       
8708       
8709        <p>f = 2.0 * <b>omega</b> * sin(<a href="#phi">phi</a>)&nbsp;
8710        <br>
8711
8712
8713
8714
8715
8716
8717f* = 2.0 * <b>omega</b> * cos(<a href="#phi">phi</a>)</p>
8718
8719
8720
8721
8722
8723
8724
8725     
8726     
8727     
8728     
8729     
8730     
8731      </ul>
8732
8733
8734
8735
8736
8737
8738 </td>
8739
8740
8741
8742
8743
8744
8745 </tr>
8746
8747
8748
8749
8750
8751
8752 <tr>
8753
8754
8755
8756
8757
8758
8759 <td style="vertical-align: top;"> 
8760     
8761     
8762     
8763     
8764     
8765     
8766      <p><a name="outflow_damping_width"></a><b>outflow_damping_width</b></p>
8767
8768
8769
8770
8771
8772
8773
8774      </td>
8775
8776
8777
8778
8779
8780
8781 <td style="vertical-align: top;">I</td>
8782
8783
8784
8785
8786
8787
8788
8789      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(20,
8790nx/2</span> or <span style="font-style: italic;">ny/2)</span></td>
8791
8792
8793
8794
8795
8796
8797
8798      <td style="vertical-align: top;">Width of
8799the damping range in the vicinity of the outflow (gridpoints).<br>
8800
8801
8802
8803
8804
8805
8806
8807      <br>
8808
8809
8810
8811
8812
8813
8814
8815When using non-cyclic lateral boundaries (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
8816or <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
8817a smoothing has to be applied to the
8818velocity field in the vicinity of the outflow in order to suppress any
8819reflections of outgoing disturbances. This parameter controlls the
8820horizontal range to which the smoothing is applied. The range is given
8821in gridpoints counted from the respective outflow boundary. For further
8822details about the smoothing see parameter <a href="chapter_4.1.html#km_damp_max">km_damp_max</a>,
8823which defines the magnitude of the damping.</td>
8824
8825
8826
8827
8828
8829
8830 </tr>
8831
8832
8833
8834
8835
8836
8837
8838    <tr>
8839
8840
8841
8842
8843
8844
8845 <td style="vertical-align: top;"> 
8846     
8847     
8848     
8849     
8850     
8851     
8852      <p><a name="overshoot_limit_e"></a><b>overshoot_limit_e</b></p>
8853
8854
8855
8856
8857
8858
8859
8860      </td>
8861
8862
8863
8864
8865
8866
8867 <td style="vertical-align: top;">R</td>
8868
8869
8870
8871
8872
8873
8874
8875      <td style="vertical-align: top;"><i>0.0</i></td>
8876
8877
8878
8879
8880
8881
8882
8883      <td style="vertical-align: top;"> 
8884     
8885     
8886     
8887     
8888     
8889     
8890      <p>Allowed limit
8891for the overshooting of subgrid-scale TKE in
8892case that the upstream-spline scheme is switched on (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
8893      </p>
8894
8895
8896
8897
8898
8899
8900 
8901     
8902     
8903     
8904     
8905     
8906     
8907      <p>By deafult, if cut-off of overshoots is switched
8908on for the
8909upstream-spline scheme (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>),
8910no overshoots are permitted at all. If <b>overshoot_limit_e</b>
8911is given a non-zero value, overshoots with the respective
8912amplitude (both upward and downward) are allowed.&nbsp; </p>
8913
8914
8915
8916
8917
8918
8919
8920     
8921     
8922     
8923     
8924     
8925     
8926      <p>Only positive values are allowed for <b>overshoot_limit_e</b>.</p>
8927
8928
8929
8930
8931
8932
8933
8934      </td>
8935
8936
8937
8938
8939
8940
8941 </tr>
8942
8943
8944
8945
8946
8947
8948 <tr>
8949
8950
8951
8952
8953
8954
8955 <td style="vertical-align: top;"> 
8956     
8957     
8958     
8959     
8960     
8961     
8962      <p><a name="overshoot_limit_pt"></a><b>overshoot_limit_pt</b></p>
8963
8964
8965
8966
8967
8968
8969
8970      </td>
8971
8972
8973
8974
8975
8976
8977 <td style="vertical-align: top;">R</td>
8978
8979
8980
8981
8982
8983
8984
8985      <td style="vertical-align: top;"><i>0.0</i></td>
8986
8987
8988
8989
8990
8991
8992
8993      <td style="vertical-align: top;"> 
8994     
8995     
8996     
8997     
8998     
8999     
9000      <p>Allowed limit
9001for the overshooting of potential temperature in
9002case that the upstream-spline scheme is switched on (in K).&nbsp; </p>
9003
9004
9005
9006
9007
9008
9009
9010     
9011     
9012     
9013     
9014     
9015     
9016      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9017      </p>
9018
9019
9020
9021
9022
9023
9024 
9025     
9026     
9027     
9028     
9029     
9030     
9031      <p>Only positive values are allowed for <b>overshoot_limit_pt</b>.</p>
9032
9033
9034
9035
9036
9037
9038
9039      </td>
9040
9041
9042
9043
9044
9045
9046 </tr>
9047
9048
9049
9050
9051
9052
9053 <tr>
9054
9055
9056
9057
9058
9059
9060 <td style="vertical-align: top;"> 
9061     
9062     
9063     
9064     
9065     
9066     
9067      <p><a name="overshoot_limit_u"></a><b>overshoot_limit_u</b></p>
9068
9069
9070
9071
9072
9073
9074
9075      </td>
9076
9077
9078
9079
9080
9081
9082 <td style="vertical-align: top;">R</td>
9083
9084
9085
9086
9087
9088
9089
9090      <td style="vertical-align: top;"><i>0.0</i></td>
9091
9092
9093
9094
9095
9096
9097
9098      <td style="vertical-align: top;">Allowed limit for the
9099overshooting of
9100the u-component of velocity in case that the upstream-spline scheme is
9101switched on (in m/s).
9102     
9103     
9104     
9105     
9106     
9107     
9108      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9109      </p>
9110
9111
9112
9113
9114
9115
9116 
9117     
9118     
9119     
9120     
9121     
9122     
9123      <p>Only positive values are allowed for <b>overshoot_limit_u</b>.</p>
9124
9125
9126
9127
9128
9129
9130
9131      </td>
9132
9133
9134
9135
9136
9137
9138 </tr>
9139
9140
9141
9142
9143
9144
9145 <tr>
9146
9147
9148
9149
9150
9151
9152 <td style="vertical-align: top;"> 
9153     
9154     
9155     
9156     
9157     
9158     
9159      <p><a name="overshoot_limit_v"></a><b>overshoot_limit_v</b></p>
9160
9161
9162
9163
9164
9165
9166
9167      </td>
9168
9169
9170
9171
9172
9173
9174 <td style="vertical-align: top;">R</td>
9175
9176
9177
9178
9179
9180
9181
9182      <td style="vertical-align: top;"><i>0.0</i></td>
9183
9184
9185
9186
9187
9188
9189
9190      <td style="vertical-align: top;"> 
9191     
9192     
9193     
9194     
9195     
9196     
9197      <p>Allowed limit
9198for the overshooting of the v-component of
9199velocity in case that the upstream-spline scheme is switched on
9200(in m/s).&nbsp; </p>
9201
9202
9203
9204
9205
9206
9207 
9208     
9209     
9210     
9211     
9212     
9213     
9214      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9215      </p>
9216
9217
9218
9219
9220
9221
9222 
9223     
9224     
9225     
9226     
9227     
9228     
9229      <p>Only positive values are allowed for <b>overshoot_limit_v</b>.</p>
9230
9231
9232
9233
9234
9235
9236
9237      </td>
9238
9239
9240
9241
9242
9243
9244 </tr>
9245
9246
9247
9248
9249
9250
9251 <tr>
9252
9253
9254
9255
9256
9257
9258 <td style="vertical-align: top;"> 
9259     
9260     
9261     
9262     
9263     
9264     
9265      <p><a name="overshoot_limit_w"></a><b>overshoot_limit_w</b></p>
9266
9267
9268
9269
9270
9271
9272
9273      </td>
9274
9275
9276
9277
9278
9279
9280 <td style="vertical-align: top;">R</td>
9281
9282
9283
9284
9285
9286
9287
9288      <td style="vertical-align: top;"><i>0.0</i></td>
9289
9290
9291
9292
9293
9294
9295
9296      <td style="vertical-align: top;"> 
9297     
9298     
9299     
9300     
9301     
9302     
9303      <p>Allowed limit
9304for the overshooting of the w-component of
9305velocity in case that the upstream-spline scheme is switched on
9306(in m/s).&nbsp; </p>
9307
9308
9309
9310
9311
9312
9313 
9314     
9315     
9316     
9317     
9318     
9319     
9320      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9321      </p>
9322
9323
9324
9325
9326
9327
9328 
9329     
9330     
9331     
9332     
9333     
9334     
9335      <p>Only positive values are permitted for <b>overshoot_limit_w</b>.</p>
9336
9337
9338
9339
9340
9341
9342
9343      </td>
9344
9345
9346
9347
9348
9349
9350 </tr>
9351
9352
9353
9354
9355
9356
9357 <tr>
9358
9359
9360
9361
9362
9363
9364 <td style="vertical-align: top;"> 
9365     
9366     
9367     
9368     
9369     
9370     
9371      <p><a name="passive_scalar"></a><b>passive_scalar</b></p>
9372
9373
9374
9375
9376
9377
9378
9379      </td>
9380
9381
9382
9383
9384
9385
9386 <td style="vertical-align: top;">L</td>
9387
9388
9389
9390
9391
9392
9393
9394      <td style="vertical-align: top;"><i>.F.</i></td>
9395
9396
9397
9398
9399
9400
9401
9402      <td style="vertical-align: top;"> 
9403     
9404     
9405     
9406     
9407     
9408     
9409      <p>Parameter to
9410switch on the prognostic equation for a passive
9411scalar. <br>
9412
9413
9414
9415
9416
9417
9418 </p>
9419
9420
9421
9422
9423
9424
9425 
9426     
9427     
9428     
9429     
9430     
9431     
9432      <p>The initial vertical profile
9433of s can be set via parameters <a href="#s_surface">s_surface</a>,
9434      <a href="#s_vertical_gradient">s_vertical_gradient</a>
9435and&nbsp; <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.
9436Boundary conditions can be set via <a href="#s_surface_initial_change">s_surface_initial_change</a>
9437and <a href="#surface_scalarflux">surface_scalarflux</a>.&nbsp;
9438      </p>
9439
9440
9441
9442
9443
9444
9445 
9446     
9447     
9448     
9449     
9450     
9451     
9452      <p><b>Note:</b> <br>
9453
9454
9455
9456
9457
9458
9459
9460With <span style="font-weight: bold;">passive_scalar</span>
9461switched
9462on, the simultaneous use of humidity (see&nbsp;<a href="#humidity">humidity</a>)
9463is impossible.</p>
9464
9465
9466
9467
9468
9469
9470 </td>
9471
9472
9473
9474
9475
9476
9477 </tr>
9478
9479
9480
9481
9482
9483
9484 <tr>
9485
9486      <td style="vertical-align: top;"><a name="pch_index"></a><span style="font-weight: bold;">pch_index</span></td>
9487
9488      <td style="vertical-align: top;">I</td>
9489
9490      <td style="vertical-align: top;"><span style="font-style: italic;">0</span></td>
9491
9492      <td style="vertical-align: top;">Grid point index (scalar) of the upper boundary of the plant canopy layer.<br>
9493
9494      <br>
9495
9496Above <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>
9497
9498    </tr>
9499
9500    <tr>
9501
9502
9503
9504
9505
9506
9507 <td style="vertical-align: top;"> 
9508     
9509     
9510     
9511     
9512     
9513     
9514      <p><a name="phi"></a><b>phi</b></p>
9515
9516
9517
9518
9519
9520
9521
9522      </td>
9523
9524
9525
9526
9527
9528
9529 <td style="vertical-align: top;">R</td>
9530
9531
9532
9533
9534
9535
9536
9537      <td style="vertical-align: top;"><i>55.0</i></td>
9538
9539
9540
9541
9542
9543
9544
9545      <td style="vertical-align: top;"> 
9546     
9547     
9548     
9549     
9550     
9551     
9552      <p>Geographical
9553latitude (in degrees).&nbsp; </p>
9554
9555
9556
9557
9558
9559
9560 
9561     
9562     
9563     
9564     
9565     
9566     
9567      <p>The value of
9568this parameter determines the value of the
9569Coriolis parameters f and f*, provided that the angular velocity (see <a href="#omega">omega</a>)
9570is non-zero.</p>
9571
9572
9573
9574
9575
9576
9577 </td>
9578
9579
9580
9581
9582
9583
9584 </tr>
9585
9586
9587
9588
9589
9590
9591 <tr>
9592
9593      <td style="vertical-align: top;"><a name="plant_canopy"></a><span style="font-weight: bold;">plant_canopy</span></td>
9594
9595      <td style="vertical-align: top;">L</td>
9596
9597      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9598
9599      <td style="vertical-align: top;">Switch for the plant_canopy_model.<br>
9600
9601      <br>
9602
9603If <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>
9604
9605The
9606impact of a plant canopy on a turbulent flow is considered by an
9607additional drag term in the momentum equations and an additional sink
9608term in the prognostic equation for the subgrid-scale TKE. These
9609additional 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>
9610
9611By 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>,
9612the canopy acts as an additional source or sink, respectively, of
9613scalar concentration. The source/sink strength is dependent on the
9614scalar concentration at the leaf surface, which is generally constant
9615with time in PALM and which can be specified by specifying the
9616parameter <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>
9617specified in the parameter file is not used in the model. Instead the
9618near-surface heat flux is derived from an expontial function that is
9619dependent on the cumulative leaf area index. <br> 
9620
9621      <br>
9622
9623      <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>
9624
9625    </tr>
9626
9627    <tr>
9628
9629
9630
9631
9632
9633
9634 <td style="vertical-align: top;"> 
9635     
9636     
9637     
9638     
9639     
9640     
9641      <p><a name="prandtl_layer"></a><b>prandtl_layer</b></p>
9642
9643
9644
9645
9646
9647
9648
9649      </td>
9650
9651
9652
9653
9654
9655
9656 <td style="vertical-align: top;">L</td>
9657
9658
9659
9660
9661
9662
9663
9664      <td style="vertical-align: top;"><i>.T.</i></td>
9665
9666
9667
9668
9669
9670
9671
9672      <td style="vertical-align: top;"> 
9673     
9674     
9675     
9676     
9677     
9678     
9679      <p>Parameter to
9680switch on a Prandtl layer.&nbsp; </p>
9681
9682
9683
9684
9685
9686
9687 
9688     
9689     
9690     
9691     
9692     
9693     
9694      <p>By default,
9695a Prandtl layer is switched on at the bottom
9696boundary between z = 0 and z = 0.5 * <a href="#dz">dz</a>
9697(the first computational grid point above ground for u, v and the
9698scalar quantities).
9699In this case, at the bottom boundary, free-slip conditions for u and v
9700(see <a href="#bc_uv_b">bc_uv_b</a>)
9701are not allowed. Likewise, laminar
9702simulations with constant eddy diffusivities (<a href="#km_constant">km_constant</a>)
9703are forbidden.&nbsp; </p>
9704
9705
9706
9707
9708
9709
9710 
9711     
9712     
9713     
9714     
9715     
9716     
9717      <p>With Prandtl-layer
9718switched off, the TKE boundary condition <a href="#bc_e_b">bc_e_b</a>
9719= '<i>(u*)**2+neumann'</i> must not be used and is
9720automatically
9721changed to <i>'neumann'</i> if necessary.&nbsp; Also,
9722the pressure
9723boundary condition <a href="#bc_p_b">bc_p_b</a>
9724= <i>'neumann+inhomo'</i>&nbsp; is not allowed. </p>
9725
9726
9727
9728
9729
9730
9731
9732     
9733     
9734     
9735     
9736     
9737     
9738      <p>The roughness length is declared via the parameter <a href="#roughness_length">roughness_length</a>.</p>
9739
9740
9741
9742
9743
9744
9745
9746      </td>
9747
9748
9749
9750
9751
9752
9753 </tr>
9754
9755
9756
9757
9758
9759
9760 <tr>
9761
9762
9763
9764
9765
9766
9767 <td style="vertical-align: top;"> 
9768     
9769     
9770     
9771     
9772     
9773     
9774      <p><a name="precipitation"></a><b>precipitation</b></p>
9775
9776
9777
9778
9779
9780
9781
9782      </td>
9783
9784
9785
9786
9787
9788
9789 <td style="vertical-align: top;">L</td>
9790
9791
9792
9793
9794
9795
9796
9797      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9798
9799
9800
9801
9802
9803
9804 <td style="vertical-align: top;"> 
9805     
9806     
9807     
9808     
9809     
9810     
9811      <p>Parameter to switch
9812on the precipitation scheme.<br>
9813
9814
9815
9816
9817
9818
9819 </p>
9820
9821
9822
9823
9824
9825
9826 
9827     
9828     
9829     
9830     
9831     
9832     
9833      <p>For
9834precipitation processes PALM uses a simplified Kessler
9835scheme. This scheme only considers the
9836so-called autoconversion, that means the generation of rain water by
9837coagulation of cloud drops among themselves. Precipitation begins and
9838is immediately removed from the flow as soon as the liquid water
9839content exceeds the critical value of 0.5 g/kg.</p>
9840
9841
9842
9843
9844
9845
9846     
9847     
9848     
9849     
9850     
9851     
9852      <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>
9853
9854
9855
9856
9857
9858
9859 </td>
9860
9861
9862
9863
9864
9865
9866 </tr>
9867
9868
9869
9870
9871
9872
9873
9874    <tr>
9875
9876
9877
9878
9879
9880
9881      <td style="vertical-align: top;"><a name="pt_reference"></a><span style="font-weight: bold;">pt_reference</span></td>
9882
9883
9884
9885
9886
9887
9888      <td style="vertical-align: top;">R</td>
9889
9890
9891
9892
9893
9894
9895      <td style="vertical-align: top;"><span style="font-style: italic;">use horizontal average as
9896refrence</span></td>
9897
9898
9899
9900
9901
9902
9903      <td style="vertical-align: top;">Reference
9904temperature to be used in all buoyancy terms (in K).<br>
9905
9906
9907
9908
9909
9910
9911      <br>
9912
9913
9914
9915
9916
9917
9918By
9919default, the instantaneous horizontal average over the total model
9920domain is used.<br>
9921
9922
9923
9924
9925
9926
9927      <br>
9928
9929
9930
9931
9932
9933
9934      <span style="font-weight: bold;">Attention:</span><br>
9935
9936
9937
9938
9939
9940
9941In 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>
9942
9943
9944
9945
9946
9947
9948    </tr>
9949
9950
9951
9952
9953
9954
9955    <tr>
9956
9957
9958
9959
9960
9961
9962 <td style="vertical-align: top;"> 
9963     
9964     
9965     
9966     
9967     
9968     
9969      <p><a name="pt_surface"></a><b>pt_surface</b></p>
9970
9971
9972
9973
9974
9975
9976
9977      </td>
9978
9979
9980
9981
9982
9983
9984 <td style="vertical-align: top;">R</td>
9985
9986
9987
9988
9989
9990
9991
9992      <td style="vertical-align: top;"><i>300.0</i></td>
9993
9994
9995
9996
9997
9998
9999
10000      <td style="vertical-align: top;"> 
10001     
10002     
10003     
10004     
10005     
10006     
10007      <p>Surface
10008potential temperature (in K).&nbsp; </p>
10009
10010
10011
10012
10013
10014
10015 
10016     
10017     
10018     
10019     
10020     
10021     
10022      <p>This
10023parameter assigns the value of the potential temperature
10024      <span style="font-weight: bold;">pt</span> at the surface (k=0)<b>.</b> Starting from this value,
10025the
10026initial vertical temperature profile is constructed with <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10027and <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level
10028      </a>.
10029This profile is also used for the 1d-model as a stationary profile.</p>
10030
10031
10032
10033
10034
10035
10036     
10037     
10038     
10039     
10040     
10041     
10042      <p><span style="font-weight: bold;">Attention:</span><br>
10043
10044
10045
10046
10047
10048
10049In case of ocean runs (see <a href="#ocean">ocean</a>),
10050this parameter gives the temperature value at the sea surface, which is
10051at k=nzt. The profile is then constructed from the surface down to the
10052bottom of the model.</p>
10053
10054
10055
10056
10057
10058
10059
10060      </td>
10061
10062
10063
10064
10065
10066
10067 </tr>
10068
10069
10070
10071
10072
10073
10074 <tr>
10075
10076
10077
10078
10079
10080
10081 <td style="vertical-align: top;"> 
10082     
10083     
10084     
10085     
10086     
10087     
10088      <p><a name="pt_surface_initial_change"></a><b>pt_surface_initial</b>
10089      <br>
10090
10091
10092
10093
10094
10095
10096 <b>_change</b></p>
10097
10098
10099
10100
10101
10102
10103 </td>
10104
10105
10106
10107
10108
10109
10110 <td style="vertical-align: top;">R</td>
10111
10112
10113
10114
10115
10116
10117 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
10118
10119
10120
10121
10122
10123
10124 </td>
10125
10126
10127
10128
10129
10130
10131
10132      <td style="vertical-align: top;"> 
10133     
10134     
10135     
10136     
10137     
10138     
10139      <p>Change in
10140surface temperature to be made at the beginning of
10141the 3d run
10142(in K).&nbsp; </p>
10143
10144
10145
10146
10147
10148
10149 
10150     
10151     
10152     
10153     
10154     
10155     
10156      <p>If <b>pt_surface_initial_change</b>
10157is set to a non-zero
10158value, the near surface sensible heat flux is not allowed to be given
10159simultaneously (see <a href="#surface_heatflux">surface_heatflux</a>).</p>
10160
10161
10162
10163
10164
10165
10166
10167      </td>
10168
10169
10170
10171
10172
10173
10174 </tr>
10175
10176
10177
10178
10179
10180
10181 <tr>
10182
10183
10184
10185
10186
10187
10188 <td style="vertical-align: top;"> 
10189     
10190     
10191     
10192     
10193     
10194     
10195      <p><a name="pt_vertical_gradient"></a><b>pt_vertical_gradient</b></p>
10196
10197
10198
10199
10200
10201
10202
10203      </td>
10204
10205
10206
10207
10208
10209
10210 <td style="vertical-align: top;">R (10)</td>
10211
10212
10213
10214
10215
10216
10217
10218      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
10219
10220
10221
10222
10223
10224
10225
10226      <td style="vertical-align: top;"> 
10227     
10228     
10229     
10230     
10231     
10232     
10233      <p>Temperature
10234gradient(s) of the initial temperature profile (in
10235K
10236/ 100 m).&nbsp; </p>
10237
10238
10239
10240
10241
10242
10243 
10244     
10245     
10246     
10247     
10248     
10249     
10250      <p>This temperature gradient
10251holds starting from the height&nbsp;
10252level defined by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>
10253(precisely: for all uv levels k where zu(k) &gt;
10254pt_vertical_gradient_level,
10255pt_init(k) is set: pt_init(k) = pt_init(k-1) + dzu(k) * <b>pt_vertical_gradient</b>)
10256up to the top boundary or up to the next height level defined
10257by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>.
10258A total of 10 different gradients for 11 height intervals (10 intervals
10259if <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>(1)
10260= <i>0.0</i>) can be assigned. The surface temperature is
10261assigned via <a href="#pt_surface">pt_surface</a>.&nbsp;
10262      </p>
10263
10264
10265
10266
10267
10268
10269 
10270     
10271     
10272     
10273     
10274     
10275     
10276      <p>Example:&nbsp; </p>
10277
10278
10279
10280
10281
10282
10283 
10284     
10285     
10286     
10287     
10288     
10289     
10290      <ul>
10291
10292
10293
10294
10295
10296
10297 
10298       
10299       
10300       
10301       
10302       
10303       
10304        <p><b>pt_vertical_gradient</b>
10305= <i>1.0</i>, <i>0.5</i>,&nbsp; <br>
10306
10307
10308
10309
10310
10311
10312
10313        <b>pt_vertical_gradient_level</b> = <i>500.0</i>,
10314        <i>1000.0</i>,</p>
10315
10316
10317
10318
10319
10320
10321 
10322     
10323     
10324     
10325     
10326     
10327     
10328      </ul>
10329
10330
10331
10332
10333
10334
10335 
10336     
10337     
10338     
10339     
10340     
10341     
10342      <p>That
10343defines the temperature profile to be neutrally
10344stratified
10345up to z = 500.0 m with a temperature given by <a href="#pt_surface">pt_surface</a>.
10346For 500.0 m &lt; z &lt;= 1000.0 m the temperature gradient is
103471.0 K /
10348100 m and for z &gt; 1000.0 m up to the top boundary it is
103490.5 K / 100 m (it is assumed that the assigned height levels correspond
10350with uv levels).</p>
10351
10352
10353
10354
10355
10356
10357     
10358     
10359     
10360     
10361     
10362     
10363      <p><span style="font-weight: bold;">Attention:</span><br>
10364
10365
10366
10367
10368
10369
10370In case of ocean runs (see <a href="chapter_4.1.html#ocean">ocean</a>),
10371the profile is constructed like described above, but starting from the
10372sea surface (k=nzt) down to the bottom boundary of the model. Height
10373levels 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>
10374
10375
10376
10377
10378
10379
10380 </td>
10381
10382
10383
10384
10385
10386
10387 </tr>
10388
10389
10390
10391
10392
10393
10394 <tr>
10395
10396
10397
10398
10399
10400
10401 <td style="vertical-align: top;"> 
10402     
10403     
10404     
10405     
10406     
10407     
10408      <p><a name="pt_vertical_gradient_level"></a><b>pt_vertical_gradient</b>
10409      <br>
10410
10411
10412
10413
10414
10415
10416 <b>_level</b></p>
10417
10418
10419
10420
10421
10422
10423 </td>
10424
10425
10426
10427
10428
10429
10430 <td style="vertical-align: top;">R (10)</td>
10431
10432
10433
10434
10435
10436
10437 <td style="vertical-align: top;"> 
10438     
10439     
10440     
10441     
10442     
10443     
10444      <p><i>10 *</i>&nbsp;
10445      <span style="font-style: italic;">0.0</span><br>
10446
10447
10448
10449
10450
10451
10452
10453      </p>
10454
10455
10456
10457
10458
10459
10460 </td>
10461
10462
10463
10464
10465
10466
10467 <td style="vertical-align: top;">
10468     
10469     
10470     
10471     
10472     
10473     
10474      <p>Height level from which on the temperature gradient defined by
10475      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10476is effective (in m).&nbsp; </p>
10477
10478
10479
10480
10481
10482
10483 
10484     
10485     
10486     
10487     
10488     
10489     
10490      <p>The height levels have to be assigned in ascending order. The
10491default values result in a neutral stratification regardless of the
10492values of <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10493(unless the top boundary of the model is higher than 100000.0 m).
10494For the piecewise construction of temperature profiles see <a href="#pt_vertical_gradient">pt_vertical_gradient</a>.</p>
10495
10496
10497
10498
10499
10500
10501      <span style="font-weight: bold;">Attention:</span><br>
10502
10503
10504
10505
10506
10507
10508In 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.
10509      </td>
10510
10511
10512
10513
10514
10515
10516 </tr>
10517
10518
10519
10520
10521
10522
10523 <tr>
10524
10525
10526
10527
10528
10529
10530 <td style="vertical-align: top;"> 
10531     
10532     
10533     
10534     
10535     
10536     
10537      <p><a name="q_surface"></a><b>q_surface</b></p>
10538
10539
10540
10541
10542
10543
10544
10545      </td>
10546
10547
10548
10549
10550
10551
10552 <td style="vertical-align: top;">R</td>
10553
10554
10555
10556
10557
10558
10559
10560      <td style="vertical-align: top;"><i>0.0</i></td>
10561
10562
10563
10564
10565
10566
10567
10568      <td style="vertical-align: top;"> 
10569     
10570     
10571     
10572     
10573     
10574     
10575      <p>Surface
10576specific humidity / total water content (kg/kg).&nbsp; </p>
10577
10578
10579
10580
10581
10582
10583 
10584     
10585     
10586     
10587     
10588     
10589     
10590      <p>This
10591parameter assigns the value of the specific humidity q at
10592the surface (k=0).&nbsp; Starting from this value, the initial
10593humidity
10594profile is constructed with&nbsp; <a href="#q_vertical_gradient">q_vertical_gradient</a>
10595and <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
10596This profile is also used for the 1d-model as a stationary profile.</p>
10597
10598
10599
10600
10601
10602
10603
10604      </td>
10605
10606
10607
10608
10609
10610
10611 </tr>
10612
10613
10614
10615
10616
10617
10618 <tr>
10619
10620
10621
10622
10623
10624
10625 <td style="vertical-align: top;"> 
10626     
10627     
10628     
10629     
10630     
10631     
10632      <p><a name="q_surface_initial_change"></a><b>q_surface_initial</b>
10633      <br>
10634
10635
10636
10637
10638
10639
10640 <b>_change</b></p>
10641
10642
10643
10644
10645
10646
10647 </td>
10648
10649
10650
10651
10652
10653
10654 <td style="vertical-align: top;">R<br>
10655
10656
10657
10658
10659
10660
10661 </td>
10662
10663
10664
10665
10666
10667
10668 <td style="vertical-align: top;"><i>0.0</i></td>
10669
10670
10671
10672
10673
10674
10675
10676      <td style="vertical-align: top;"> 
10677     
10678     
10679     
10680     
10681     
10682     
10683      <p>Change in
10684surface specific humidity / total water content to
10685be made at the beginning
10686of the 3d run (kg/kg).&nbsp; </p>
10687
10688
10689
10690
10691
10692
10693 
10694     
10695     
10696     
10697     
10698     
10699     
10700      <p>If <b>q_surface_initial_change</b><i>
10701      </i>is set to a
10702non-zero value the
10703near surface latent heat flux (water flux) is not allowed to be given
10704simultaneously (see <a href="#surface_waterflux">surface_waterflux</a>).</p>
10705
10706
10707
10708
10709
10710
10711
10712      </td>
10713
10714
10715
10716
10717
10718
10719 </tr>
10720
10721
10722
10723
10724
10725
10726 <tr>
10727
10728
10729
10730
10731
10732
10733 <td style="vertical-align: top;"> 
10734     
10735     
10736     
10737     
10738     
10739     
10740      <p><a name="q_vertical_gradient"></a><b>q_vertical_gradient</b></p>
10741
10742
10743
10744
10745
10746
10747
10748      </td>
10749
10750
10751
10752
10753
10754
10755 <td style="vertical-align: top;">R (10)</td>
10756
10757
10758
10759
10760
10761
10762
10763      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
10764
10765
10766
10767
10768
10769
10770
10771      <td style="vertical-align: top;"> 
10772     
10773     
10774     
10775     
10776     
10777     
10778      <p>Humidity
10779gradient(s) of the initial humidity profile
10780(in 1/100 m).&nbsp; </p>
10781
10782
10783
10784
10785
10786
10787 
10788     
10789     
10790     
10791     
10792     
10793     
10794      <p>This humidity gradient
10795holds starting from the height
10796level&nbsp; defined by <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>
10797(precisely: for all uv levels k, where zu(k) &gt;
10798q_vertical_gradient_level,
10799q_init(k) is set: q_init(k) = q_init(k-1) + dzu(k) * <b>q_vertical_gradient</b>)
10800up to the top boundary or up to the next height level defined
10801by <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
10802A total of 10 different gradients for 11 height intervals (10 intervals
10803if <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>(1)
10804= <i>0.0</i>) can be asigned. The surface humidity is
10805assigned
10806via <a href="#q_surface">q_surface</a>. </p>
10807
10808
10809
10810
10811
10812
10813
10814     
10815     
10816     
10817     
10818     
10819     
10820      <p>Example:&nbsp; </p>
10821
10822
10823
10824
10825
10826
10827 
10828     
10829     
10830     
10831     
10832     
10833     
10834      <ul>
10835
10836
10837
10838
10839
10840
10841 
10842       
10843       
10844       
10845       
10846       
10847       
10848        <p><b>q_vertical_gradient</b>
10849= <i>0.001</i>, <i>0.0005</i>,&nbsp; <br>
10850
10851
10852
10853
10854
10855
10856
10857        <b>q_vertical_gradient_level</b> = <i>500.0</i>,
10858        <i>1000.0</i>,</p>
10859
10860
10861
10862
10863
10864
10865 
10866     
10867     
10868     
10869     
10870     
10871     
10872      </ul>
10873
10874
10875<