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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 (see <a href="#prandtl_layer">prandtl_layer</a>), 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- and yz-cross-sections of
3259the total model domain remains constant throughout the run depending on the chosen <a href="#conserve_volume_flow_mode">conserve_volume_flow_mode</a>.<br><br>Note that&nbsp;<span style="font-weight: bold;">conserve_volume_flow</span>
3260= <span style="font-style: italic;">.T.</span> requires <a href="#dp_external">dp_external</a> = <span style="font-style: italic;">.F.</span> .<br>
3261
3262
3263
3264
3265
3266
3267
3268      </td>
3269
3270
3271
3272
3273
3274
3275 </tr>
3276
3277
3278
3279
3280
3281
3282 <tr><td style="vertical-align: top;"><span style="font-weight: bold;"><a name="conserve_volume_flow_mode"></a>conserve_volume_flow_mode</span></td><td style="vertical-align: top;">C * 16</td><td style="vertical-align: top;"><span style="font-style: italic;">'default'</span></td><td>Modus of volume flow conservation.<br><br>The following values are allowed:<br><p style="font-style: normal;"><span style="font-style: italic;">'default'</span>
3283      </p>
3284
3285
3286
3287
3288
3289
3290 
3291     
3292     
3293     
3294     
3295     
3296     
3297      <ul><p>Per default, PALM uses&nbsp;<span style="font-style: italic;">'initial_profiles'</span> for cyclic lateral boundary conditions (<a href="#bc_lr">bc_lr</a> = <span style="font-style: italic;">'cyclic'</span> and <a href="#bc_ns">bc_ns</a> = <span style="font-style: italic;">'cyclic'</span>) and&nbsp;<span style="font-style: italic;">'inflow_profile'</span> for non-cyclic lateral boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> /= <span style="font-style: italic;">'cyclic'</span> or <a href="chapter_4.1.html#bc_ns">bc_ns</a> /= <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3298
3299
3300
3301
3302
3303
3304 
3305     
3306     
3307     
3308     
3309     
3310     
3311      <p style="font-style: italic;">'initial_profiles' </p>
3312
3313
3314
3315
3316
3317
3318
3319     
3320     
3321     
3322     
3323     
3324     
3325      <ul><p>The
3326target volume flow&nbsp;is calculated at t=0 from the initial profiles
3327of u and v.&nbsp;This setting is only allowed for&nbsp;cyclic lateral
3328boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> = <span style="font-style: italic;">'cyclic'</span> and <a href="chapter_4.1.html#bc_ns">bc_ns</a> = <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3329
3330
3331
3332
3333
3334
3335 
3336     
3337     
3338     
3339     
3340     
3341     
3342      <p style="font-style: normal;"><span style="font-style: italic;">'inflow_profile'</span>
3343      </p>
3344
3345
3346
3347
3348
3349
3350 
3351     
3352     
3353     
3354     
3355     
3356     
3357      <ul><p>The
3358target volume flow&nbsp;is&nbsp;calculated at every timestep from the
3359inflow profile of&nbsp;u or v, respectively. This setting&nbsp;is only
3360allowed for&nbsp;non-cyclic lateral boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> /= <span style="font-style: italic;">'cyclic'</span> or <a href="chapter_4.1.html#bc_ns">bc_ns</a> /= <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3361
3362
3363
3364
3365
3366
3367 
3368     
3369     
3370     
3371     
3372     
3373     
3374      <p style="font-style: italic;">'bulk_velocity' </p>
3375
3376
3377
3378
3379
3380
3381
3382     
3383     
3384     
3385     
3386     
3387     
3388      <ul><p>The target volume flow is calculated from a predefined bulk velocity (see <a href="#u_bulk">u_bulk</a> and <a href="#v_bulk">v_bulk</a>). This setting is only allowed for&nbsp;cyclic lateral boundary conditions (<a href="chapter_4.1.html#bc_lr">bc_lr</a> = <span style="font-style: italic;">'cyclic'</span> and <a href="chapter_4.1.html#bc_ns">bc_ns</a> = <span style="font-style: italic;">'cyclic'</span>).</p></ul>
3389
3390
3391
3392
3393
3394
3395 
3396     
3397     
3398     
3399     
3400     
3401     
3402      <span style="font-style: italic;"></span>Note that&nbsp;<span style="font-weight: bold;">conserve_volume_flow_mode</span>
3403only comes into effect if <a href="#conserve_volume_flow">conserve_volume_flow</a> = <span style="font-style: italic;">.T. .</span> </td></tr><tr>
3404
3405      <td style="vertical-align: top;"><a name="cthf"></a><span style="font-weight: bold;">cthf</span></td>
3406
3407      <td style="vertical-align: top;">R</td>
3408
3409      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3410
3411      <td style="vertical-align: top;">Average heat flux that is prescribed at the top of the plant canopy.<br>
3412
3413
3414      <br>
3415
3416
3417If <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>
3418
3419
3420It is assumed that solar radiation penetrates the canopy and warms the
3421foliage which, in turn, warms the air in contact with it. <br>
3422
3423
3424Note: Instead of using the value prescribed by <a href="#surface_heatflux">surface_heatflux</a>,
3425the near surface heat flux is determined from an exponential function
3426that is dependent on the cumulative leaf_area_index (Shaw and Schumann
3427(1992, Boundary Layer Meteorol., 61, 47-64)).</td>
3428
3429    </tr>
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="cut_spline_overshoot"></a><b>cut_spline_overshoot</b></p>
3446
3447
3448
3449
3450
3451
3452
3453      </td>
3454
3455
3456
3457
3458
3459
3460 <td style="vertical-align: top;">L</td>
3461
3462
3463
3464
3465
3466
3467
3468      <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span></td>
3469
3470
3471
3472
3473
3474
3475 <td style="vertical-align: top;"> 
3476     
3477     
3478     
3479     
3480     
3481     
3482      <p>Cuts off of
3483so-called overshoots, which can occur with the
3484upstream-spline scheme.&nbsp; </p>
3485
3486
3487
3488
3489
3490
3491 
3492     
3493     
3494     
3495     
3496     
3497     
3498      <p><font color="#000000">The cubic splines tend to overshoot in
3499case of discontinuous changes of variables between neighbouring grid
3500points.</font><font color="#ff0000"> </font><font color="#000000">This
3501may lead to errors in calculating the advection tendency.</font>
3502Choice
3503of <b>cut_spline_overshoot</b> = <i>.TRUE.</i>
3504(switched on by
3505default)
3506allows variable values not to exceed an interval defined by the
3507respective adjacent grid points. This interval can be adjusted
3508seperately for every prognostic variable (see initialization parameters
3509      <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>,
3510etc.). This might be necessary in case that the
3511default interval has a non-tolerable effect on the model
3512results.&nbsp; </p>
3513
3514
3515
3516
3517
3518
3519 
3520     
3521     
3522     
3523     
3524     
3525     
3526      <p>Overshoots may also be removed
3527using the parameters <a href="#ups_limit_e">ups_limit_e</a>,
3528      <a href="#ups_limit_pt">ups_limit_pt</a>,
3529etc. as well as by applying a long-filter (see <a href="#long_filter_factor">long_filter_factor</a>).</p>
3530
3531
3532
3533
3534
3535
3536
3537      </td>
3538
3539
3540
3541
3542
3543
3544 </tr>
3545
3546
3547
3548
3549
3550
3551 <tr>
3552
3553
3554
3555
3556
3557
3558 <td style="vertical-align: top;"> 
3559     
3560     
3561     
3562     
3563     
3564     
3565      <p><a name="damp_level_1d"></a><b>damp_level_1d</b></p>
3566
3567
3568
3569
3570
3571
3572
3573      </td>
3574
3575
3576
3577
3578
3579
3580 <td style="vertical-align: top;">R</td>
3581
3582
3583
3584
3585
3586
3587
3588      <td style="vertical-align: top;"><span style="font-style: italic;">zu(nz+1)</span></td>
3589
3590
3591
3592
3593
3594
3595
3596      <td style="vertical-align: top;"> 
3597     
3598     
3599     
3600     
3601     
3602     
3603      <p>Height where
3604the damping layer begins in the 1d-model
3605(in m).&nbsp; </p>
3606
3607
3608
3609
3610
3611
3612 
3613     
3614     
3615     
3616     
3617     
3618     
3619      <p>This parameter is used to
3620switch on a damping layer for the
36211d-model, which is generally needed for the damping of inertia
3622oscillations. Damping is done by gradually increasing the value
3623of the eddy diffusivities about 10% per vertical grid level
3624(starting with the value at the height given by <b>damp_level_1d</b>,
3625or possibly from the next grid pint above), i.e. K<sub>m</sub>(k+1)
3626=
36271.1 * K<sub>m</sub>(k).
3628The values of K<sub>m</sub> are limited to 10 m**2/s at
3629maximum.&nbsp; <br>
3630
3631
3632
3633
3634
3635
3636
3637This parameter only comes into effect if the 1d-model is switched on
3638for
3639the initialization of the 3d-model using <a href="#initializing_actions">initializing_actions</a>
3640= <span style="font-style: italic;">'set_1d-model_profiles'</span>.
3641      <br>
3642
3643
3644
3645
3646
3647
3648 </p>
3649
3650
3651
3652
3653
3654
3655 </td>
3656
3657
3658
3659
3660
3661
3662 </tr>
3663
3664
3665
3666
3667
3668
3669 <tr>
3670
3671
3672
3673
3674
3675
3676 <td style="vertical-align: top;"><a name="dissipation_1d"></a><span style="font-weight: bold;">dissipation_1d</span><br>
3677
3678
3679
3680
3681
3682
3683
3684      </td>
3685
3686
3687
3688
3689
3690
3691 <td style="vertical-align: top;">C*20<br>
3692
3693
3694
3695
3696
3697
3698
3699      </td>
3700
3701
3702
3703
3704
3705
3706 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
3707
3708
3709
3710
3711
3712
3713 <span style="font-style: italic;">model'</span><br>
3714
3715
3716
3717
3718
3719
3720 </td>
3721
3722
3723
3724
3725
3726
3727
3728      <td style="vertical-align: top;">Calculation method for
3729the energy dissipation term in the TKE equation of the 1d-model.<br>
3730
3731
3732
3733
3734
3735
3736
3737      <br>
3738
3739
3740
3741
3742
3743
3744
3745By default the dissipation is calculated as in the 3d-model using diss
3746= (0.19 + 0.74 * l / l_grid) * e**1.5 / l.<br>
3747
3748
3749
3750
3751
3752
3753 <br>
3754
3755
3756
3757
3758
3759
3760
3761Setting <span style="font-weight: bold;">dissipation_1d</span>
3762= <span style="font-style: italic;">'detering'</span>
3763forces the dissipation to be calculated as diss = 0.064 * e**1.5 / l.<br>
3764
3765
3766
3767
3768
3769
3770
3771      </td>
3772
3773
3774
3775
3776
3777
3778 </tr>
3779    <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
3780parameter is used to switch on/off an external pressure gradient as
3781driving force. The external pressure gradient is controlled by the
3782parameters <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
3783limit 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
3784must hold the condition zu(0) &lt;= <b>dp_level_b</b>
3785&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
3786that there is no upper limit of the vertical range because the external
3787pressure 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>
3788
3789
3790
3791
3792
3793
3794    <tr>
3795
3796      <td style="vertical-align: top;"><a name="drag_coefficient"></a><span style="font-weight: bold;">drag_coefficient</span></td>
3797
3798      <td style="vertical-align: top;">R</td>
3799
3800      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3801
3802      <td style="vertical-align: top;">Drag coefficient used in the plant canopy model.<br>
3803
3804      <br>
3805
3806This 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>
3807
3808    </tr>
3809
3810    <tr>
3811
3812
3813
3814
3815
3816
3817 <td style="vertical-align: top;"> 
3818     
3819     
3820     
3821     
3822     
3823     
3824      <p><a name="dt"></a><b>dt</b></p>
3825
3826
3827
3828
3829
3830
3831 </td>
3832
3833
3834
3835
3836
3837
3838
3839      <td style="vertical-align: top;">R</td>
3840
3841
3842
3843
3844
3845
3846 <td style="vertical-align: top;"><span style="font-style: italic;">variable</span></td>
3847
3848
3849
3850
3851
3852
3853
3854      <td style="vertical-align: top;"> 
3855     
3856     
3857     
3858     
3859     
3860     
3861      <p>Time step for
3862the 3d-model (in s).&nbsp; </p>
3863
3864
3865
3866
3867
3868
3869 
3870     
3871     
3872     
3873     
3874     
3875     
3876      <p>By default, (i.e.
3877if a Runge-Kutta scheme is used, see <a href="#timestep_scheme">timestep_scheme</a>)
3878the value of the time step is calculating after each time step
3879(following the time step criteria) and
3880used for the next step.</p>
3881
3882
3883
3884
3885
3886
3887 
3888     
3889     
3890     
3891     
3892     
3893     
3894      <p>If the user assigns <b>dt</b>
3895a value, then the time step is
3896fixed to this value throughout the whole run (whether it fulfills the
3897time step
3898criteria or not). However, changes are allowed for restart runs,
3899because <b>dt</b> can also be used as a <a href="chapter_4.2.html#dt_laufparameter">run
3900parameter</a>.&nbsp; </p>
3901
3902
3903
3904
3905
3906
3907 
3908     
3909     
3910     
3911     
3912     
3913     
3914      <p>In case that the
3915calculated time step meets the condition<br>
3916
3917
3918
3919
3920
3921
3922 </p>
3923
3924
3925
3926
3927
3928
3929 
3930     
3931     
3932     
3933     
3934     
3935     
3936      <ul>
3937
3938
3939
3940
3941
3942
3943
3944       
3945       
3946       
3947       
3948       
3949       
3950        <p><b>dt</b> &lt; 0.00001 * <a href="chapter_4.2.html#dt_max">dt_max</a> (with dt_max
3951= 20.0)</p>
3952
3953
3954
3955
3956
3957
3958 
3959     
3960     
3961     
3962     
3963     
3964     
3965      </ul>
3966
3967
3968
3969
3970
3971
3972 
3973     
3974     
3975     
3976     
3977     
3978     
3979      <p>the simulation will be
3980aborted. Such situations usually arise
3981in case of any numerical problem / instability which causes a
3982non-realistic increase of the wind speed.&nbsp; </p>
3983
3984
3985
3986
3987
3988
3989 
3990     
3991     
3992     
3993     
3994     
3995     
3996      <p>A
3997small time step due to a large mean horizontal windspeed
3998speed may be enlarged by using a coordinate transformation (see <a href="#galilei_transformation">galilei_transformation</a>),
3999in order to spare CPU time.<br>
4000
4001
4002
4003
4004
4005
4006 </p>
4007
4008
4009
4010
4011
4012
4013 
4014     
4015     
4016     
4017     
4018     
4019     
4020      <p>If the
4021leapfrog timestep scheme is used (see <a href="#timestep_scheme">timestep_scheme</a>)
4022a temporary time step value dt_new is calculated first, with dt_new = <a href="chapter_4.2.html#fcl_factor">cfl_factor</a>
4023* dt_crit where dt_crit is the maximum timestep allowed by the CFL and
4024diffusion condition. Next it is examined whether dt_new exceeds or
4025falls below the
4026value of the previous timestep by at
4027least +5 % / -2%. If it is smaller, <span style="font-weight: bold;">dt</span>
4028= dt_new is immediately used for the next timestep. If it is larger,
4029then <span style="font-weight: bold;">dt </span>=
40301.02 * dt_prev
4031(previous timestep) is used as the new timestep, however the time
4032step is only increased if the last change of the time step is dated
4033back at
4034least 30 iterations. If dt_new is located in the interval mentioned
4035above, then dt
4036does not change at all. By doing so, permanent time step changes as
4037well as large
4038sudden changes (increases) in the time step are avoided.</p>
4039
4040
4041
4042
4043
4044
4045 </td>
4046
4047
4048
4049
4050
4051
4052
4053    </tr>
4054
4055
4056
4057
4058
4059
4060 <tr>
4061
4062
4063
4064
4065
4066
4067 <td style="vertical-align: top;">
4068     
4069     
4070     
4071     
4072     
4073     
4074      <p><a name="dt_pr_1d"></a><b>dt_pr_1d</b></p>
4075
4076
4077
4078
4079
4080
4081
4082      </td>
4083
4084
4085
4086
4087
4088
4089 <td style="vertical-align: top;">R</td>
4090
4091
4092
4093
4094
4095
4096
4097      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4098
4099
4100
4101
4102
4103
4104
4105      <td style="vertical-align: top;"> 
4106     
4107     
4108     
4109     
4110     
4111     
4112      <p>Temporal
4113interval of vertical profile output of the 1D-model
4114(in s).&nbsp; </p>
4115
4116
4117
4118
4119
4120
4121 
4122     
4123     
4124     
4125     
4126     
4127     
4128      <p>Data are written in ASCII
4129format to file <a href="chapter_3.4.html#LIST_PROFIL_1D">LIST_PROFIL_1D</a>.
4130This parameter is only in effect if the 1d-model has been switched on
4131for the
4132initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4133= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4134
4135
4136
4137
4138
4139
4140
4141      </td>
4142
4143
4144
4145
4146
4147
4148 </tr>
4149
4150
4151
4152
4153
4154
4155 <tr>
4156
4157
4158
4159
4160
4161
4162 <td style="vertical-align: top;"> 
4163     
4164     
4165     
4166     
4167     
4168     
4169      <p><a name="dt_run_control_1d"></a><b>dt_run_control_1d</b></p>
4170
4171
4172
4173
4174
4175
4176
4177      </td>
4178
4179
4180
4181
4182
4183
4184 <td style="vertical-align: top;">R</td>
4185
4186
4187
4188
4189
4190
4191
4192      <td style="vertical-align: top;"><span style="font-style: italic;">60.0</span></td>
4193
4194
4195
4196
4197
4198
4199 <td style="vertical-align: top;"> 
4200     
4201     
4202     
4203     
4204     
4205     
4206      <p>Temporal interval of
4207runtime control output of the 1d-model
4208(in s).&nbsp; </p>
4209
4210
4211
4212
4213
4214
4215 
4216     
4217     
4218     
4219     
4220     
4221     
4222      <p>Data are written in ASCII
4223format to file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
4224This parameter is only in effect if the 1d-model is switched on for the
4225initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4226= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4227
4228
4229
4230
4231
4232
4233
4234      </td>
4235
4236
4237
4238
4239
4240
4241 </tr>
4242
4243
4244
4245
4246
4247
4248 <tr>
4249
4250
4251
4252
4253
4254
4255 <td style="vertical-align: top;"> 
4256     
4257     
4258     
4259     
4260     
4261     
4262      <p><a name="dx"></a><b>dx</b></p>
4263
4264
4265
4266
4267
4268
4269
4270      </td>
4271
4272
4273
4274
4275
4276
4277 <td style="vertical-align: top;">R</td>
4278
4279
4280
4281
4282
4283
4284
4285      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4286
4287
4288
4289
4290
4291
4292 <td style="vertical-align: top;"> 
4293     
4294     
4295     
4296     
4297     
4298     
4299      <p>Horizontal grid
4300spacing along the x-direction (in m).&nbsp; </p>
4301
4302
4303
4304
4305
4306
4307 
4308     
4309     
4310     
4311     
4312     
4313     
4314      <p>Along
4315x-direction only a constant grid spacing is allowed.</p>
4316
4317
4318
4319
4320
4321
4322     
4323     
4324     
4325     
4326     
4327     
4328      <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>
4329and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4330
4331
4332
4333
4334
4335
4336 </td>
4337
4338
4339
4340
4341
4342
4343
4344    </tr>
4345
4346
4347
4348
4349
4350
4351 <tr>
4352
4353
4354
4355
4356
4357
4358 <td style="vertical-align: top;">
4359     
4360     
4361     
4362     
4363     
4364     
4365      <p><a name="dy"></a><b>dy</b></p>
4366
4367
4368
4369
4370
4371
4372
4373      </td>
4374
4375
4376
4377
4378
4379
4380 <td style="vertical-align: top;">R</td>
4381
4382
4383
4384
4385
4386
4387
4388      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4389
4390
4391
4392
4393
4394
4395 <td style="vertical-align: top;"> 
4396     
4397     
4398     
4399     
4400     
4401     
4402      <p>Horizontal grid
4403spacing along the y-direction (in m).&nbsp; </p>
4404
4405
4406
4407
4408
4409
4410 
4411     
4412     
4413     
4414     
4415     
4416     
4417      <p>Along y-direction only a constant grid spacing is allowed.</p>
4418
4419
4420
4421
4422
4423
4424     
4425     
4426     
4427     
4428     
4429     
4430      <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>
4431and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4432
4433
4434
4435
4436
4437
4438 </td>
4439
4440
4441
4442
4443
4444
4445
4446    </tr>
4447
4448
4449
4450
4451
4452
4453 <tr>
4454
4455
4456
4457
4458
4459
4460 <td style="vertical-align: top;">
4461     
4462     
4463     
4464     
4465     
4466     
4467      <p><a name="dz"></a><b>dz</b></p>
4468
4469
4470
4471
4472
4473
4474
4475      </td>
4476
4477
4478
4479
4480
4481
4482 <td style="vertical-align: top;">R</td>
4483
4484
4485
4486
4487
4488
4489
4490      <td style="vertical-align: top;"><br>
4491
4492
4493
4494
4495
4496
4497 </td>
4498
4499
4500
4501
4502
4503
4504 <td style="vertical-align: top;"> 
4505     
4506     
4507     
4508     
4509     
4510     
4511      <p>Vertical grid
4512spacing (in m).&nbsp; </p>
4513
4514
4515
4516
4517
4518
4519 
4520     
4521     
4522     
4523     
4524     
4525     
4526      <p>This parameter must be
4527assigned by the user, because no
4528default value is given.<br>
4529
4530
4531
4532
4533
4534
4535 </p>
4536
4537
4538
4539
4540
4541
4542 
4543     
4544     
4545     
4546     
4547     
4548     
4549      <p>By default, the
4550model uses constant grid spacing along z-direction, but it can be
4551stretched using the parameters <a href="#dz_stretch_level">dz_stretch_level</a>
4552and <a href="#dz_stretch_factor">dz_stretch_factor</a>.
4553In case of stretching, a maximum allowed grid spacing can be given by <a href="#dz_max">dz_max</a>.<br>
4554
4555
4556
4557
4558
4559
4560 </p>
4561
4562
4563
4564
4565
4566
4567 
4568     
4569     
4570     
4571     
4572     
4573     
4574      <p>Assuming
4575a constant <span style="font-weight: bold;">dz</span>,
4576the scalar levels (zu) are calculated directly by:&nbsp; </p>
4577
4578
4579
4580
4581
4582
4583
4584     
4585     
4586     
4587     
4588     
4589     
4590      <ul>
4591
4592
4593
4594
4595
4596
4597 
4598       
4599       
4600       
4601       
4602       
4603       
4604        <p>zu(0) = - dz * 0.5&nbsp; <br>
4605
4606
4607
4608
4609
4610
4611
4612zu(1) = dz * 0.5</p>
4613
4614
4615
4616
4617
4618
4619 
4620     
4621     
4622     
4623     
4624     
4625     
4626      </ul>
4627
4628
4629
4630
4631
4632
4633 
4634     
4635     
4636     
4637     
4638     
4639     
4640      <p>The w-levels lie
4641half between them:&nbsp; </p>
4642
4643
4644
4645
4646
4647
4648 
4649     
4650     
4651     
4652     
4653     
4654     
4655      <ul>
4656
4657
4658
4659
4660
4661
4662 
4663       
4664       
4665       
4666       
4667       
4668       
4669        <p>zw(k) =
4670( zu(k) + zu(k+1) ) * 0.5</p>
4671
4672
4673
4674
4675
4676
4677 
4678     
4679     
4680     
4681     
4682     
4683     
4684      </ul>
4685
4686
4687
4688
4689
4690
4691 </td>
4692
4693
4694
4695
4696
4697
4698 </tr>
4699
4700
4701
4702
4703
4704
4705
4706    <tr>
4707
4708
4709
4710
4711
4712
4713      <td style="vertical-align: top;"><a name="dz_max"></a><span style="font-weight: bold;">dz_max</span></td>
4714
4715
4716
4717
4718
4719
4720      <td style="vertical-align: top;">R</td>
4721
4722
4723
4724
4725
4726
4727      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4728
4729
4730
4731
4732
4733
4734      <td style="vertical-align: top;">Allowed maximum vertical grid
4735spacing (in m).<br>
4736
4737
4738
4739
4740
4741
4742      <br>
4743
4744
4745
4746
4747
4748
4749If the vertical grid is stretched
4750(see <a href="#dz_stretch_factor">dz_stretch_factor</a>
4751and <a href="#dz_stretch_level">dz_stretch_level</a>),
4752      <span style="font-weight: bold;">dz_max</span> can
4753be used to limit the vertical grid spacing.</td>
4754
4755
4756
4757
4758
4759
4760    </tr>
4761
4762
4763
4764
4765
4766
4767    <tr>
4768
4769
4770
4771
4772
4773
4774
4775      <td style="vertical-align: top;"> 
4776     
4777     
4778     
4779     
4780     
4781     
4782      <p><a name="dz_stretch_factor"></a><b>dz_stretch_factor</b></p>
4783
4784
4785
4786
4787
4788
4789
4790      </td>
4791
4792
4793
4794
4795
4796
4797 <td style="vertical-align: top;">R</td>
4798
4799
4800
4801
4802
4803
4804
4805      <td style="vertical-align: top;"><span style="font-style: italic;">1.08</span></td>
4806
4807
4808
4809
4810
4811
4812 <td style="vertical-align: top;"> 
4813     
4814     
4815     
4816     
4817     
4818     
4819      <p>Stretch factor for a
4820vertically stretched grid (see <a href="#dz_stretch_level">dz_stretch_level</a>).&nbsp;
4821      </p>
4822
4823
4824
4825
4826
4827
4828 
4829     
4830     
4831     
4832     
4833     
4834     
4835      <p>The stretch factor should not exceed a value of
4836approx. 1.10 -
48371.12, otherwise the discretization errors due to the stretched grid not
4838negligible any more. (refer Kalnay de Rivas)</p>
4839
4840
4841
4842
4843
4844
4845 </td>
4846
4847
4848
4849
4850
4851
4852 </tr>
4853
4854
4855
4856
4857
4858
4859
4860    <tr>
4861
4862
4863
4864
4865
4866
4867 <td style="vertical-align: top;"> 
4868     
4869     
4870     
4871     
4872     
4873     
4874      <p><a name="dz_stretch_level"></a><b>dz_stretch_level</b></p>
4875
4876
4877
4878
4879
4880
4881
4882      </td>
4883
4884
4885
4886
4887
4888
4889 <td style="vertical-align: top;">R</td>
4890
4891
4892
4893
4894
4895
4896
4897      <td style="vertical-align: top;"><span style="font-style: italic;">100000.0</span><br>
4898
4899
4900
4901
4902
4903
4904 </td>
4905
4906
4907
4908
4909
4910
4911
4912      <td style="vertical-align: top;"> 
4913     
4914     
4915     
4916     
4917     
4918     
4919      <p>Height level
4920above/below which the grid is to be stretched
4921vertically (in m).&nbsp; </p>
4922
4923
4924
4925
4926
4927
4928 
4929     
4930     
4931     
4932     
4933     
4934     
4935      <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
4936vertically. The vertical grid
4937spacings <a href="#dz">dz</a>
4938above this level are calculated as&nbsp; </p>
4939
4940
4941
4942
4943
4944
4945 
4946     
4947     
4948     
4949     
4950     
4951     
4952      <ul>
4953
4954
4955
4956
4957
4958
4959 
4960       
4961       
4962       
4963       
4964       
4965       
4966        <p><b>dz</b>(k+1)
4967= <b>dz</b>(k) * <a href="#dz_stretch_factor">dz_stretch_factor</a></p>
4968
4969
4970
4971
4972
4973
4974
4975     
4976     
4977     
4978     
4979     
4980     
4981      </ul>
4982
4983
4984
4985
4986
4987
4988 
4989     
4990     
4991     
4992     
4993     
4994     
4995      <p>and used as spacings for the scalar levels (zu).
4996The
4997w-levels are then defined as:&nbsp; </p>
4998
4999
5000
5001
5002
5003
5004 
5005     
5006     
5007     
5008     
5009     
5010     
5011      <ul>
5012
5013
5014
5015
5016
5017
5018 
5019       
5020       
5021       
5022       
5023       
5024       
5025        <p>zw(k)
5026= ( zu(k) + zu(k+1) ) * 0.5.
5027
5028 
5029     
5030      </p>
5031
5032
5033
5034
5035     
5036     
5037     
5038     
5039      </ul>
5040
5041
5042
5043
5044     
5045     
5046     
5047     
5048      <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
5049vertically. The vertical grid
5050spacings <a href="chapter_4.1.html#dz">dz</a> below this level are calculated correspondingly as
5051
5052 
5053     
5054      </p>
5055
5056
5057
5058
5059     
5060     
5061     
5062     
5063      <ul>
5064
5065
5066
5067
5068       
5069       
5070       
5071       
5072        <p><b>dz</b>(k-1)
5073= <b>dz</b>(k) * <a href="chapter_4.1.html#dz_stretch_factor">dz_stretch_factor</a>.</p>
5074
5075
5076
5077
5078     
5079     
5080     
5081     
5082      </ul>
5083
5084
5085
5086
5087
5088
5089 </td>
5090
5091
5092
5093
5094
5095
5096 </tr>
5097
5098
5099
5100
5101
5102
5103
5104    <tr>
5105
5106
5107
5108
5109
5110      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_init"></a>e_init</span></td>
5111
5112
5113
5114
5115
5116      <td style="vertical-align: top;">R</td>
5117
5118
5119
5120
5121
5122      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5123
5124
5125
5126
5127
5128      <td>Initial subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5129
5130
5131
5132
5133
5134
5135
5136      <br>
5137
5138
5139
5140
5141
5142
5143This
5144option 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>
5145
5146
5147
5148
5149
5150    </tr>
5151
5152
5153
5154
5155
5156    <tr>
5157
5158
5159
5160
5161
5162
5163 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_min"></a>e_min</span></td>
5164
5165
5166
5167
5168
5169
5170
5171      <td style="vertical-align: top;">R</td>
5172
5173
5174
5175
5176
5177
5178 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5179
5180
5181
5182
5183
5184
5185 <td>Minimum
5186subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5187
5188
5189
5190
5191
5192
5193
5194      <br>
5195
5196
5197
5198
5199
5200
5201This
5202option&nbsp;adds artificial viscosity to the flow by ensuring that
5203the
5204subgrid-scale TKE does not fall below the minimum threshold <span style="font-weight: bold;">e_min</span>.</td>
5205
5206
5207
5208
5209
5210
5211 </tr>
5212
5213
5214
5215
5216
5217
5218
5219    <tr>
5220
5221
5222
5223
5224
5225
5226 <td style="vertical-align: top;"> 
5227     
5228     
5229     
5230     
5231     
5232     
5233      <p><a name="end_time_1d"></a><b>end_time_1d</b></p>
5234
5235
5236
5237
5238
5239
5240
5241      </td>
5242
5243
5244
5245
5246
5247
5248 <td style="vertical-align: top;">R</td>
5249
5250
5251
5252
5253
5254
5255
5256      <td style="vertical-align: top;"><span style="font-style: italic;">864000.0</span><br>
5257
5258
5259
5260
5261
5262
5263 </td>
5264
5265
5266
5267
5268
5269
5270
5271      <td style="vertical-align: top;"> 
5272     
5273     
5274     
5275     
5276     
5277     
5278      <p>Time to be
5279simulated for the 1d-model (in s).&nbsp; </p>
5280
5281
5282
5283
5284
5285
5286 
5287     
5288     
5289     
5290     
5291     
5292     
5293      <p>The
5294default value corresponds to a simulated time of 10 days.
5295Usually, after such a period the inertia oscillations have completely
5296decayed and the solution of the 1d-model can be regarded as stationary
5297(see <a href="#damp_level_1d">damp_level_1d</a>).
5298This parameter is only in effect if the 1d-model is switched on for the
5299initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
5300= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
5301
5302
5303
5304
5305
5306
5307
5308      </td>
5309
5310
5311
5312
5313
5314
5315 </tr>
5316
5317
5318
5319
5320
5321
5322 <tr>
5323
5324
5325
5326
5327
5328
5329 <td style="vertical-align: top;"> 
5330     
5331     
5332     
5333     
5334     
5335     
5336      <p><a name="fft_method"></a><b>fft_method</b></p>
5337
5338
5339
5340
5341
5342
5343
5344      </td>
5345
5346
5347
5348
5349
5350
5351 <td style="vertical-align: top;">C * 20</td>
5352
5353
5354
5355
5356
5357
5358
5359      <td style="vertical-align: top;"><span style="font-style: italic;">'system-</span><br style="font-style: italic;">
5360
5361
5362
5363
5364
5365
5366 <span style="font-style: italic;">specific'</span></td>
5367
5368
5369
5370
5371
5372
5373
5374      <td style="vertical-align: top;"> 
5375     
5376     
5377     
5378     
5379     
5380     
5381      <p>FFT-method to
5382be used.<br>
5383
5384
5385
5386
5387
5388
5389 </p>
5390
5391
5392
5393
5394
5395
5396 
5397     
5398     
5399     
5400     
5401     
5402     
5403      <p><br>
5404
5405
5406
5407
5408
5409
5410
5411The fast fourier transformation (FFT) is used for solving the
5412perturbation pressure equation with a direct method (see <a href="chapter_4.2.html#psolver">psolver</a>)
5413and for calculating power spectra (see optional software packages,
5414section <a href="chapter_4.2.html#spectra_package">4.2</a>).</p>
5415
5416
5417
5418
5419
5420
5421
5422     
5423     
5424     
5425     
5426     
5427     
5428      <p><br>
5429
5430
5431
5432
5433
5434
5435
5436By default, system-specific, optimized routines from external
5437vendor libraries are used. However, these are available only on certain
5438computers and there are more or less severe restrictions concerning the
5439number of gridpoints to be used with them.<br>
5440
5441
5442
5443
5444
5445
5446 </p>
5447
5448
5449
5450
5451
5452
5453 
5454     
5455     
5456     
5457     
5458     
5459     
5460      <p>There
5461are two other PALM internal methods available on every
5462machine (their respective source code is part of the PALM source code):</p>
5463
5464
5465
5466
5467
5468
5469
5470     
5471     
5472     
5473     
5474     
5475     
5476      <p>1.: The <span style="font-weight: bold;">Temperton</span>-method
5477from Clive Temperton (ECWMF) which is computationally very fast and
5478switched on with <b>fft_method</b> = <span style="font-style: italic;">'temperton-algorithm'</span>.
5479The number of horizontal gridpoints (nx+1, ny+1) to be used with this
5480method must be composed of prime factors 2, 3 and 5.<br>
5481
5482
5483
5484
5485
5486
5487 </p>
5488
5489
5490
5491
5492
5493
5494
54952.: The <span style="font-weight: bold;">Singleton</span>-method
5496which is very slow but has no restrictions concerning the number of
5497gridpoints to be used with, switched on with <b>fft_method</b>
5498= <span style="font-style: italic;">'singleton-algorithm'</span>.
5499      </td>
5500
5501
5502
5503
5504
5505
5506 </tr>
5507
5508
5509
5510
5511
5512
5513 <tr>
5514
5515
5516
5517
5518
5519
5520 <td style="vertical-align: top;"> 
5521     
5522     
5523     
5524     
5525     
5526     
5527      <p><a name="galilei_transformation"></a><b>galilei_transformation</b></p>
5528
5529
5530
5531
5532
5533
5534
5535      </td>
5536
5537
5538
5539
5540
5541
5542 <td style="vertical-align: top;">L</td>
5543
5544
5545
5546
5547
5548
5549
5550      <td style="vertical-align: top;"><i>.F.</i></td>
5551
5552
5553
5554
5555
5556
5557
5558      <td style="vertical-align: top;">Application of a
5559Galilei-transformation to the
5560coordinate
5561system of the model.<br>
5562
5563
5564
5565
5566
5567
5568     
5569     
5570     
5571     
5572     
5573     
5574      <p>With <b>galilei_transformation</b>
5575= <i>.T.,</i> a so-called
5576Galilei-transformation is switched on which ensures that the coordinate
5577system of the model is moved along with the geostrophical wind.
5578Alternatively, the model domain can be moved along with the averaged
5579horizontal wind (see <a href="#use_ug_for_galilei_tr">use_ug_for_galilei_tr</a>,
5580this can and will naturally change in time). With this method,
5581numerical inaccuracies of the Piascek - Williams - scheme (concerns in
5582particular the momentum advection) are minimized. Beyond that, in the
5583majority of cases the lower relative velocities in the moved system
5584permit a larger time step (<a href="#dt">dt</a>).
5585Switching the transformation on is only worthwhile if the geostrophical
5586wind (ug, vg)
5587and the averaged horizontal wind clearly deviate from the value 0. In
5588each case, the distance the coordinate system has been moved is written
5589to the file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.&nbsp;
5590      </p>
5591
5592
5593
5594
5595
5596
5597 
5598     
5599     
5600     
5601     
5602     
5603     
5604      <p>Non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
5605and <a href="#bc_ns">bc_ns</a>), the specification
5606of a gestrophic
5607wind that is not constant with height
5608as well as e.g. stationary inhomogeneities at the bottom boundary do
5609not allow the use of this transformation.</p>
5610
5611
5612
5613
5614
5615
5616 </td>
5617
5618
5619
5620
5621
5622
5623 </tr>
5624
5625
5626
5627
5628
5629
5630
5631    <tr>
5632
5633
5634
5635
5636
5637
5638 <td style="vertical-align: top;"> 
5639     
5640     
5641     
5642     
5643     
5644     
5645      <p><a name="grid_matching"></a><b>grid_matching</b></p>
5646
5647
5648
5649
5650
5651
5652
5653      </td>
5654
5655
5656
5657
5658
5659
5660 <td style="vertical-align: top;">C * 6</td>
5661
5662
5663
5664
5665
5666
5667
5668      <td style="vertical-align: top;"><span style="font-style: italic;">'match'</span></td>
5669
5670
5671
5672
5673
5674
5675 <td style="vertical-align: top;">Variable to adjust the
5676subdomain
5677sizes in parallel runs.<br>
5678
5679
5680
5681
5682
5683
5684 <br>
5685
5686
5687
5688
5689
5690
5691
5692For <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>,
5693the subdomains are forced to have an identical
5694size on all processors. In this case the processor numbers in the
5695respective directions of the virtual processor net must fulfill certain
5696divisor conditions concerning the grid point numbers in the three
5697directions (see <a href="#nx">nx</a>, <a href="#ny">ny</a>
5698and <a href="#nz">nz</a>).
5699Advantage of this method is that all PEs bear the same computational
5700load.<br>
5701
5702
5703
5704
5705
5706
5707 <br>
5708
5709
5710
5711
5712
5713
5714
5715There is no such restriction by default, because then smaller
5716subdomains are allowed on those processors which
5717form the right and/or north boundary of the virtual processor grid. On
5718all other processors the subdomains are of same size. Whether smaller
5719subdomains are actually used, depends on the number of processors and
5720the grid point numbers used. Information about the respective settings
5721are 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>
5722
5723
5724
5725
5726
5727
5728
5729      <br>
5730
5731
5732
5733
5734
5735
5736
5737When 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>)
5738only <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>
5739is allowed.<br>
5740
5741
5742
5743
5744
5745
5746 <br>
5747
5748
5749
5750
5751
5752
5753 <b>Note:</b><br>
5754
5755
5756
5757
5758
5759
5760
5761In some cases for small processor numbers there may be a very bad load
5762balancing among the
5763processors which may reduce the performance of the code.</td>
5764
5765
5766
5767
5768
5769
5770 </tr>
5771
5772
5773
5774
5775
5776
5777
5778    <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
5779switch on the prognostic equation for specific
5780humidity q.<br>
5781
5782
5783
5784
5785
5786
5787 </p>
5788
5789
5790
5791
5792
5793
5794 
5795     
5796     
5797     
5798     
5799     
5800     
5801      <p>The initial vertical
5802profile 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>
5803and <a href="chapter_4.1.html#q_vertical_gradient_level">q_vertical_gradient_level</a>.&nbsp;
5804Boundary conditions can be set via <a href="chapter_4.1.html#q_surface_initial_change">q_surface_initial_change</a>
5805and <a href="chapter_4.1.html#surface_waterflux">surface_waterflux</a>.<br>
5806
5807
5808
5809
5810
5811
5812
5813      </p>
5814
5815
5816
5817
5818
5819
5820
5821If the condensation scheme is switched on (<a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
5822= .TRUE.), q becomes the total liquid water content (sum of specific
5823humidity 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>),
5824this parameter defines the vertical thickness of the turbulent layer up
5825to which the turbulence extracted at the recycling plane (see <a href="chapter_4.1.html#recycling_width">recycling_width</a>)
5826shall be imposed to the inflow. Above this level the turbulence signal
5827is linearly damped to zero. The transition range within which the
5828signal 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>
5829
5830
5831
5832
5833
5834
5835 <td style="vertical-align: top;"><a name="inflow_disturbance_begin"></a><b>inflow_disturbance_<br>
5836
5837
5838
5839
5840
5841
5842
5843begin</b></td>
5844
5845
5846
5847
5848
5849
5850 <td style="vertical-align: top;">I</td>
5851
5852
5853
5854
5855
5856
5857
5858      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(10,</span><br style="font-style: italic;">
5859
5860
5861
5862
5863
5864
5865 <span style="font-style: italic;">nx/2 or ny/2)</span></td>
5866
5867
5868
5869
5870
5871
5872
5873      <td style="vertical-align: top;">Lower
5874limit of the horizontal range for which random perturbations are to be
5875imposed on the horizontal velocity field (gridpoints).<br>
5876
5877
5878
5879
5880
5881
5882 <br>
5883
5884
5885
5886
5887
5888
5889
5890If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5891or <a href="#bc_ns">bc_ns</a>),
5892this parameter gives the gridpoint number (counted horizontally from
5893the inflow)&nbsp; from which on perturbations are imposed on the
5894horizontal velocity field. Perturbations must be switched on with
5895parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5896
5897
5898
5899
5900
5901
5902
5903    </tr>
5904
5905
5906
5907
5908
5909
5910 <tr>
5911
5912
5913
5914
5915
5916
5917 <td style="vertical-align: top;"><a name="inflow_disturbance_end"></a><b>inflow_disturbance_<br>
5918
5919
5920
5921
5922
5923
5924
5925end</b></td>
5926
5927
5928
5929
5930
5931
5932 <td style="vertical-align: top;">I</td>
5933
5934
5935
5936
5937
5938
5939
5940      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(100,</span><br style="font-style: italic;">
5941
5942
5943
5944
5945
5946
5947 <span style="font-style: italic;">3/4*nx or</span><br style="font-style: italic;">
5948
5949
5950
5951
5952
5953
5954 <span style="font-style: italic;">3/4*ny)</span></td>
5955
5956
5957
5958
5959
5960
5961 <td style="vertical-align: top;">Upper
5962limit of the horizontal range for which random perturbations are
5963to be imposed on the horizontal velocity field (gridpoints).<br>
5964
5965
5966
5967
5968
5969
5970 <br>
5971
5972
5973
5974
5975
5976
5977
5978If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5979or <a href="#bc_ns">bc_ns</a>),
5980this parameter gives the gridpoint number (counted horizontally from
5981the inflow)&nbsp; unto which perturbations are imposed on the
5982horizontal
5983velocity field. Perturbations must be switched on with parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5984
5985
5986
5987
5988
5989
5990
5991    </tr>
5992
5993
5994
5995
5996
5997
5998 <tr>
5999
6000
6001
6002
6003
6004
6005 <td style="vertical-align: top;">
6006     
6007     
6008     
6009     
6010     
6011     
6012      <p><a name="initializing_actions"></a><b>initializing_actions</b></p>
6013
6014
6015
6016
6017
6018
6019
6020      </td>
6021
6022
6023
6024
6025
6026
6027 <td style="vertical-align: top;">C * 100</td>
6028
6029
6030
6031
6032
6033
6034
6035      <td style="vertical-align: top;"><br>
6036
6037
6038
6039
6040
6041
6042 </td>
6043
6044
6045
6046
6047
6048
6049 <td style="vertical-align: top;"> 
6050     
6051     
6052     
6053     
6054     
6055     
6056      <p style="font-style: normal;">Initialization actions
6057to be carried out.&nbsp; </p>
6058
6059
6060
6061
6062
6063
6064 
6065     
6066     
6067     
6068     
6069     
6070     
6071      <p style="font-style: normal;">This parameter does not have a
6072default value and therefore must be assigned with each model run. For
6073restart runs <b>initializing_actions</b> = <span style="font-style: italic;">'read_restart_data'</span>
6074must be set. For the initial run of a job chain the following values
6075are allowed:&nbsp; </p>
6076
6077
6078
6079
6080
6081
6082 
6083     
6084     
6085     
6086     
6087     
6088     
6089      <p style="font-style: normal;"><span style="font-style: italic;">'set_constant_profiles'</span>
6090      </p>
6091
6092
6093
6094
6095
6096
6097 
6098     
6099     
6100     
6101     
6102     
6103     
6104      <ul>
6105
6106
6107
6108
6109
6110
6111 
6112       
6113       
6114       
6115       
6116       
6117       
6118        <p>A horizontal wind profile consisting
6119of linear sections (see <a href="#ug_surface">ug_surface</a>,
6120        <a href="#ug_vertical_gradient">ug_vertical_gradient</a>,
6121        <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>
6122and <a href="#vg_surface">vg_surface</a>, <a href="#vg_vertical_gradient">vg_vertical_gradient</a>,
6123        <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
6124respectively) as well as a vertical temperature (humidity) profile
6125consisting of
6126linear sections (see <a href="#pt_surface">pt_surface</a>,
6127        <a href="#pt_vertical_gradient">pt_vertical_gradient</a>,
6128        <a href="#q_surface">q_surface</a>
6129and <a href="#q_vertical_gradient">q_vertical_gradient</a>)
6130are assumed as initial profiles. The subgrid-scale TKE is set to 0 but K<sub>m</sub>
6131and K<sub>h</sub> are set to very small values because
6132otherwise no TKE
6133would be generated.</p>
6134
6135
6136
6137
6138
6139
6140 
6141     
6142     
6143     
6144     
6145     
6146     
6147      </ul>
6148
6149
6150
6151
6152
6153
6154 
6155     
6156     
6157     
6158     
6159     
6160     
6161      <p style="font-style: italic;">'set_1d-model_profiles' </p>
6162
6163
6164
6165
6166
6167
6168
6169     
6170     
6171     
6172     
6173     
6174     
6175      <ul>
6176
6177
6178
6179
6180
6181
6182 
6183       
6184       
6185       
6186       
6187       
6188       
6189        <p>The arrays of the 3d-model are initialized with
6190the
6191(stationary) solution of the 1d-model. These are the variables e, kh,
6192km, u, v and with Prandtl layer switched on rif, us, usws, vsws. The
6193temperature (humidity) profile consisting of linear sections is set as
6194for 'set_constant_profiles' and assumed as constant in time within the
61951d-model. For steering of the 1d-model a set of parameters with suffix
6196"_1d" (e.g. <a href="#end_time_1d">end_time_1d</a>,
6197        <a href="#damp_level_1d">damp_level_1d</a>)
6198is available.</p>
6199
6200
6201
6202
6203
6204
6205 
6206     
6207     
6208     
6209     
6210     
6211     
6212      </ul>
6213
6214
6215
6216
6217
6218
6219 
6220     
6221     
6222     
6223     
6224     
6225     
6226      <p><span style="font-style: italic;">'by_user'</span></p>
6227
6228
6229
6230
6231
6232
6233     
6234     
6235     
6236     
6237     
6238     
6239      <p style="margin-left: 40px;">The initialization of the arrays
6240of the 3d-model is under complete control of the user and has to be
6241done in routine <a href="chapter_3.5.1.html#user_init_3d_model">user_init_3d_model</a>
6242of the user-interface.<span style="font-style: italic;"></span></p>
6243
6244
6245
6246
6247
6248
6249     
6250     
6251     
6252     
6253     
6254     
6255      <p><span style="font-style: italic;">'initialize_vortex'</span>
6256      </p>
6257
6258
6259
6260
6261
6262
6263 
6264     
6265     
6266     
6267     
6268     
6269     
6270      <div style="margin-left: 40px;">The initial
6271velocity field of the
62723d-model corresponds to a
6273Rankine-vortex with vertical axis. This setting may be used to test
6274advection 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>)
6275are necessary. In order not to distort the vortex, an initial
6276horizontal wind profile constant
6277with height is necessary (to be set by <b>initializing_actions</b>
6278= <span style="font-style: italic;">'set_constant_profiles'</span>)
6279and some other conditions have to be met (neutral stratification,
6280diffusion must be
6281switched off, see <a href="#km_constant">km_constant</a>).
6282The center of the vortex is located at jc = (nx+1)/2. It
6283extends from k = 0 to k = nz+1. Its radius is 8 * <a href="#dx">dx</a>
6284and the exponentially decaying part ranges to 32 * <a href="#dx">dx</a>
6285(see init_rankine.f90). </div>
6286
6287
6288
6289
6290
6291
6292 
6293     
6294     
6295     
6296     
6297     
6298     
6299      <p><span style="font-style: italic;">'initialize_ptanom'</span>
6300      </p>
6301
6302
6303
6304
6305
6306
6307 
6308     
6309     
6310     
6311     
6312     
6313     
6314      <ul>
6315
6316
6317
6318
6319
6320
6321 
6322       
6323       
6324       
6325       
6326       
6327       
6328        <p>A 2d-Gauss-like shape disturbance
6329(x,y) is added to the
6330initial temperature field with radius 10.0 * <a href="#dx">dx</a>
6331and center at jc = (nx+1)/2. This may be used for tests of scalar
6332advection schemes
6333(see <a href="#scalar_advec">scalar_advec</a>).
6334Such tests require a horizontal wind profile constant with hight and
6335diffusion
6336switched off (see <span style="font-style: italic;">'initialize_vortex'</span>).
6337Additionally, the buoyancy term
6338must be switched of in the equation of motion&nbsp; for w (this
6339requires the user to comment out the call of <span style="font-family: monospace;">buoyancy</span> in the
6340source code of <span style="font-family: monospace;">prognostic_equations.f90</span>).</p></ul>
6341
6342
6343
6344
6345
6346
6347 
6348     
6349     
6350     
6351     
6352     
6353     
6354      <p style="font-style: italic;">'read_data_for_recycling'</p><p style="font-style: normal; margin-left: 40px;">Here,
63553d-data from a precursor run are read by the initial (main) run. The
6356precursor run is allowed to have a smaller domain along x and y
6357compared with the main run. Also, different numbers of processors can
6358be used for these two runs. Limitations are that the precursor run must
6359use cyclic horizontal boundary conditions and that the subdomains of
6360the main run must not be larger than the subdomains of the precursor
6361run. If the total domain of the main run is larger than that of the precursor
6362run, the domain is filled by cyclic repetition&nbsp;of the (cyclic)
6363precursor data. This initialization method is recommended if a
6364turbulent 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
6365combined, e.g. <b>initializing_actions</b> = <span style="font-style: italic;">'set_constant_profiles
6366initialize_vortex'</span>, but the values of <span style="font-style: italic;">'set_constant_profiles'</span>,
6367      <span style="font-style: italic;">'set_1d-model_profiles'</span>
6368, and <span style="font-style: italic;">'by_user'</span>
6369must not be given at the same time.</p>
6370
6371
6372
6373
6374
6375
6376 
6377     
6378     
6379     
6380     
6381     
6382     
6383     
6384
6385
6386
6387
6388
6389
6390 </td>
6391
6392
6393
6394
6395
6396
6397 </tr>
6398
6399
6400
6401
6402
6403
6404
6405    <tr>
6406
6407
6408
6409
6410
6411
6412 <td style="vertical-align: top;"> 
6413     
6414     
6415     
6416     
6417     
6418     
6419      <p><a name="km_constant"></a><b>km_constant</b></p>
6420
6421
6422
6423
6424
6425
6426
6427      </td>
6428
6429
6430
6431
6432
6433
6434 <td style="vertical-align: top;">R</td>
6435
6436
6437
6438
6439
6440
6441
6442      <td style="vertical-align: top;"><i>variable<br>
6443
6444
6445
6446
6447
6448
6449
6450(computed from TKE)</i></td>
6451
6452
6453
6454
6455
6456
6457 <td style="vertical-align: top;"> 
6458     
6459     
6460     
6461     
6462     
6463     
6464      <p>Constant eddy
6465diffusivities are used (laminar
6466simulations).&nbsp; </p>
6467
6468
6469
6470
6471
6472
6473 
6474     
6475     
6476     
6477     
6478     
6479     
6480      <p>If this parameter is
6481specified, both in the 1d and in the
64823d-model constant values for the eddy diffusivities are used in
6483space and time with K<sub>m</sub> = <b>km_constant</b>
6484and K<sub>h</sub> = K<sub>m</sub> / <a href="chapter_4.2.html#prandtl_number">prandtl_number</a>.
6485The prognostic equation for the subgrid-scale TKE is switched off.
6486Constant eddy diffusivities are only allowed with the Prandtl layer (<a href="#prandtl_layer">prandtl_layer</a>)
6487switched off.</p>
6488
6489
6490
6491
6492
6493
6494 </td>
6495
6496
6497
6498
6499
6500
6501 </tr>
6502
6503
6504
6505
6506
6507
6508 <tr>
6509
6510
6511
6512
6513
6514
6515 <td style="vertical-align: top;"> 
6516     
6517     
6518     
6519     
6520     
6521     
6522      <p><a name="km_damp_max"></a><b>km_damp_max</b></p>
6523
6524
6525
6526
6527
6528
6529
6530      </td>
6531
6532
6533
6534
6535
6536
6537 <td style="vertical-align: top;">R</td>
6538
6539
6540
6541
6542
6543
6544
6545      <td style="vertical-align: top;"><span style="font-style: italic;">0.5*(dx
6546or dy)</span></td>
6547
6548
6549
6550
6551
6552
6553 <td style="vertical-align: top;">Maximum
6554diffusivity used for filtering the velocity field in the vicinity of
6555the outflow (in m<sup>2</sup>/s).<br>
6556
6557
6558
6559
6560
6561
6562 <br>
6563
6564
6565
6566
6567
6568
6569
6570When using non-cyclic lateral boundaries (see <a href="#bc_lr">bc_lr</a>
6571or <a href="#bc_ns">bc_ns</a>),
6572a smoothing has to be applied to the
6573velocity field in the vicinity of the outflow in order to suppress any
6574reflections of outgoing disturbances. Smoothing is done by increasing
6575the eddy diffusivity along the horizontal direction which is
6576perpendicular to the outflow boundary. Only velocity components
6577parallel to the outflow boundary are filtered (e.g. v and w, if the
6578outflow is along x). Damping is applied from the bottom to the top of
6579the domain.<br>
6580
6581
6582
6583
6584
6585
6586 <br>
6587
6588
6589
6590
6591
6592
6593
6594The horizontal range of the smoothing is controlled by <a href="#outflow_damping_width">outflow_damping_width</a>
6595which defines the number of gridpoints (counted from the outflow
6596boundary) from where on the smoothing is applied. Starting from that
6597point, the eddy diffusivity is linearly increased (from zero to its
6598maximum value given by <span style="font-weight: bold;">km_damp_max</span>)
6599until half of the damping range width, from where it remains constant
6600up to the outflow boundary. If at a certain grid point the eddy
6601diffusivity calculated from the flow field is larger than as described
6602above, it is used instead.<br>
6603
6604
6605
6606
6607
6608
6609 <br>
6610
6611
6612
6613
6614
6615
6616
6617The default value of <span style="font-weight: bold;">km_damp_max</span>
6618has been empirically proven to be sufficient.</td>
6619
6620
6621
6622
6623
6624
6625 </tr>
6626
6627
6628
6629
6630
6631
6632 <tr>
6633
6634      <td style="vertical-align: top;"><a name="lad_surface"></a><span style="font-weight: bold;">lad_surface</span></td>
6635
6636      <td style="vertical-align: top;">R</td>
6637
6638      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
6639
6640      <td style="vertical-align: top;">Surface value of the leaf area density (in m<sup>2</sup>/m<sup>3</sup>).<br>
6641
6642      <br>
6643
6644This
6645parameter 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,
6646the leaf area density profile is constructed with <a href="#lad_vertical_gradient">lad_vertical_gradient</a>
6647and <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level
6648      </a>.</td>
6649
6650    </tr>
6651
6652    <tr>
6653
6654      <td style="vertical-align: top;"><a name="lad_vertical_gradient"></a><span style="font-weight: bold;">lad_vertical_gradient</span></td>
6655
6656      <td style="vertical-align: top;">R (10)</td>
6657
6658      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6659
6660      <td style="vertical-align: top;">Gradient(s) of the leaf area density (in&nbsp;m<sup>2</sup>/m<sup>4</sup>).<br>
6661
6662      <br>
6663
6664     
6665      <p>This leaf area density gradient
6666holds starting from the height&nbsp;
6667level defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6668(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>)
6669up 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
6670if <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>(1)
6671= <i>0.0</i>) can be assigned. The leaf area density at the surface is
6672assigned via <a href="#lad_surface">lad_surface</a>.&nbsp;
6673      </p>
6674
6675      </td>
6676
6677    </tr>
6678
6679    <tr>
6680
6681      <td style="vertical-align: top;"><a name="lad_vertical_gradient_level"></a><span style="font-weight: bold;">lad_vertical_gradient_level</span></td>
6682
6683      <td style="vertical-align: top;">R (10)</td>
6684
6685      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6686
6687      <td style="vertical-align: top;">Height level from which on the&nbsp;gradient
6688of the leaf area density defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6689is effective (in m).<br>
6690
6691      <br>
6692
6693The height levels have to be assigned in ascending order. The
6694default 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>
6695
6696    </tr>
6697
6698    <tr>
6699
6700      <td style="vertical-align: top;"><a name="leaf_surface_concentration"></a><b>leaf_surface_concentration</b></td>
6701
6702      <td style="vertical-align: top;">R</td>
6703
6704      <td style="vertical-align: top;"><i>0.0</i></td>
6705
6706      <td style="vertical-align: top;">Concentration of a passive scalar at the surface of a leaf (in K m/s).<br>
6707
6708
6709      <br>
6710
6711
6712This 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>.
6713The value of the concentration of a passive scalar at the surface of a
6714leaf is required for the parametrisation of the sources and sinks of
6715scalar concentration due to the canopy.</td>
6716
6717    </tr>
6718
6719    <tr>
6720
6721
6722
6723
6724
6725
6726
6727      <td style="vertical-align: top;"> 
6728     
6729     
6730     
6731     
6732     
6733     
6734      <p><a name="long_filter_factor"></a><b>long_filter_factor</b></p>
6735
6736
6737
6738
6739
6740
6741
6742      </td>
6743
6744
6745
6746
6747
6748
6749 <td style="vertical-align: top;">R</td>
6750
6751
6752
6753
6754
6755
6756
6757      <td style="vertical-align: top;"><i>0.0</i></td>
6758
6759
6760
6761
6762
6763
6764
6765      <td style="vertical-align: top;"> 
6766     
6767     
6768     
6769     
6770     
6771     
6772      <p>Filter factor
6773for the so-called Long-filter.<br>
6774
6775
6776
6777
6778
6779
6780 </p>
6781
6782
6783
6784
6785
6786
6787 
6788     
6789     
6790     
6791     
6792     
6793     
6794      <p><br>
6795
6796
6797
6798
6799
6800
6801
6802This filter very efficiently
6803eliminates 2-delta-waves sometimes cauesed by the upstream-spline
6804scheme (see Mahrer and
6805Pielke, 1978: Mon. Wea. Rev., 106, 818-830). It works in all three
6806directions in space. A value of <b>long_filter_factor</b>
6807= <i>0.01</i>
6808sufficiently removes the small-scale waves without affecting the
6809longer waves.<br>
6810
6811
6812
6813
6814
6815
6816 </p>
6817
6818
6819
6820
6821
6822
6823 
6824     
6825     
6826     
6827     
6828     
6829     
6830      <p>By default, the filter is
6831switched off (= <i>0.0</i>).
6832It is exclusively applied to the tendencies calculated by the
6833upstream-spline scheme (see <a href="#momentum_advec">momentum_advec</a>
6834and <a href="#scalar_advec">scalar_advec</a>),
6835not to the prognostic variables themselves. At the bottom and top
6836boundary of the model domain the filter effect for vertical
68372-delta-waves is reduced. There, the amplitude of these waves is only
6838reduced by approx. 50%, otherwise by nearly 100%.&nbsp; <br>
6839
6840
6841
6842
6843
6844
6845
6846Filter factors with values &gt; <i>0.01</i> also
6847reduce the amplitudes
6848of waves with wavelengths longer than 2-delta (see the paper by Mahrer
6849and
6850Pielke, quoted above). </p>
6851
6852
6853
6854
6855
6856
6857 </td>
6858
6859
6860
6861
6862
6863
6864 </tr>
6865
6866
6867
6868
6869
6870
6871 <tr>
6872
6873
6874
6875
6876
6877
6878      <td style="vertical-align: top;"><a name="loop_optimization"></a><span style="font-weight: bold;">loop_optimization</span></td>
6879
6880
6881
6882
6883
6884
6885      <td style="vertical-align: top;">C*16</td>
6886
6887
6888
6889
6890
6891
6892      <td style="vertical-align: top;"><span style="font-style: italic;">see right</span></td>
6893
6894
6895
6896
6897
6898
6899      <td>Method used to optimize loops for solving the prognostic equations .<br>
6900
6901
6902
6903
6904
6905
6906      <br>
6907
6908
6909
6910
6911
6912
6913By
6914default, the optimization method depends on the host on which PALM is
6915running. On machines with vector-type CPUs, single 3d-loops are used to
6916calculate each tendency term of each prognostic equation, while on all
6917other machines, all prognostic equations are solved within one big loop
6918over 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>
6919
6920
6921
6922
6923
6924
6925      <br>
6926
6927
6928
6929
6930
6931
6932The 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>
6933
6934
6935
6936
6937
6938
6939    </tr>
6940
6941
6942
6943
6944
6945
6946    <tr>
6947
6948
6949
6950
6951
6952
6953
6954      <td style="vertical-align: top;"><a name="mixing_length_1d"></a><span style="font-weight: bold;">mixing_length_1d</span><br>
6955
6956
6957
6958
6959
6960
6961
6962      </td>
6963
6964
6965
6966
6967
6968
6969 <td style="vertical-align: top;">C*20<br>
6970
6971
6972
6973
6974
6975
6976
6977      </td>
6978
6979
6980
6981
6982
6983
6984 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
6985
6986
6987
6988
6989
6990
6991 <span style="font-style: italic;">model'</span><br>
6992
6993
6994
6995
6996
6997
6998 </td>
6999
7000
7001
7002
7003
7004
7005
7006      <td style="vertical-align: top;">Mixing length used in the
70071d-model.<br>
7008
7009
7010
7011
7012
7013
7014 <br>
7015
7016
7017
7018
7019
7020
7021
7022By default the mixing length is calculated as in the 3d-model (i.e. it
7023depends on the grid spacing).<br>
7024
7025
7026
7027
7028
7029
7030 <br>
7031
7032
7033
7034
7035
7036
7037
7038By setting <span style="font-weight: bold;">mixing_length_1d</span>
7039= <span style="font-style: italic;">'blackadar'</span>,
7040the so-called Blackadar mixing length is used (l = kappa * z / ( 1 +
7041kappa * z / lambda ) with the limiting value lambda = 2.7E-4 * u_g / f).<br>
7042
7043
7044
7045
7046
7047
7048
7049      </td>
7050
7051
7052
7053
7054
7055
7056 </tr>
7057
7058
7059
7060
7061
7062
7063 
7064
7065
7066
7067
7068
7069
7070
7071    <tr>
7072
7073
7074
7075
7076
7077
7078 <td style="vertical-align: top;"> 
7079     
7080     
7081     
7082     
7083     
7084     
7085      <p><a name="momentum_advec"></a><b>momentum_advec</b></p>
7086
7087
7088
7089
7090
7091
7092
7093      </td>
7094
7095
7096
7097
7098
7099
7100 <td style="vertical-align: top;">C * 10</td>
7101
7102
7103
7104
7105
7106
7107
7108      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
7109
7110
7111
7112
7113
7114
7115
7116      <td style="vertical-align: top;"> 
7117     
7118     
7119     
7120     
7121     
7122     
7123      <p>Advection
7124scheme to be used for the momentum equations.<br>
7125
7126
7127
7128
7129
7130
7131 <br>
7132
7133
7134
7135
7136
7137
7138
7139The user can choose between the following schemes:<br>
7140
7141
7142
7143
7144
7145
7146
7147&nbsp;<br>
7148
7149
7150
7151
7152
7153
7154 <br>
7155
7156
7157
7158
7159
7160
7161 <span style="font-style: italic;">'pw-scheme'</span><br>
7162
7163
7164
7165
7166
7167
7168
7169      </p>
7170
7171
7172
7173
7174
7175
7176 
7177     
7178     
7179     
7180     
7181     
7182     
7183      <div style="margin-left: 40px;">The scheme of
7184Piascek and
7185Williams (1970, J. Comp. Phys., 6,
7186392-405) with central differences in the form C3 is used.<br>
7187
7188
7189
7190
7191
7192
7193
7194If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
7195= <span style="font-style: italic;">'leapfrog+euler'</span>
7196the
7197advection scheme is - for the Euler-timestep - automatically switched
7198to an upstream-scheme.<br>
7199
7200
7201
7202
7203
7204
7205 </div>
7206
7207
7208
7209
7210
7211
7212 
7213     
7214     
7215     
7216     
7217     
7218     
7219      <p> </p>
7220
7221
7222
7223
7224
7225
7226 
7227     
7228     
7229     
7230     
7231     
7232     
7233      <p><span style="font-style: italic;">'ups-scheme'</span><br>
7234
7235
7236
7237
7238
7239
7240
7241      </p>
7242
7243
7244
7245
7246
7247
7248 
7249     
7250     
7251     
7252     
7253     
7254     
7255      <div style="margin-left: 40px;">The
7256upstream-spline scheme is
7257used
7258(see Mahrer and Pielke,
72591978: Mon. Wea. Rev., 106, 818-830). In opposite to the
7260Piascek-Williams scheme, this is characterized by much better numerical
7261features (less numerical diffusion, better preservation of flow
7262structures, e.g. vortices), but computationally it is much more
7263expensive. In
7264addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
7265= <span style="font-style: italic;">'</span><i>euler'</i>),
7266i.e. the
7267timestep accuracy is only of first order.
7268For this reason the advection of scalar variables (see <a href="#scalar_advec">scalar_advec</a>)
7269should then also be carried out with the upstream-spline scheme,
7270because otherwise the scalar variables would
7271be subject to large numerical diffusion due to the upstream
7272scheme.&nbsp; </div>
7273
7274
7275
7276
7277
7278
7279 
7280     
7281     
7282     
7283     
7284     
7285     
7286      <p style="margin-left: 40px;">Since
7287the cubic splines used tend
7288to overshoot under
7289certain circumstances, this effect must be adjusted by suitable
7290filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
7291      <a href="#long_filter_factor">long_filter_factor</a>,
7292      <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>).
7293This is always neccessary for runs with stable stratification,
7294even if this stratification appears only in parts of the model domain.<br>
7295
7296
7297
7298
7299
7300
7301
7302      </p>
7303
7304
7305
7306
7307
7308
7309 
7310     
7311     
7312     
7313     
7314     
7315     
7316      <div style="margin-left: 40px;">With stable
7317stratification the
7318upstream-spline scheme also
7319produces gravity waves with large amplitude, which must be
7320suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
7321
7322
7323
7324
7325
7326
7327
7328      <br>
7329
7330
7331
7332
7333
7334
7335 <span style="font-weight: bold;">Important: </span>The&nbsp;
7336upstream-spline scheme is not implemented for humidity and passive
7337scalars (see&nbsp;<a href="#humidity">humidity</a>
7338and <a href="#passive_scalar">passive_scalar</a>)
7339and requires the use of a 2d-domain-decomposition. The last conditions
7340severely restricts code optimization on several machines leading to
7341very long execution times! The scheme is also not allowed for
7342non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
7343and <a href="#bc_ns">bc_ns</a>).</div>
7344
7345
7346
7347
7348
7349
7350 </td>
7351
7352
7353
7354
7355
7356
7357
7358    </tr>
7359
7360
7361
7362
7363
7364
7365 <tr>
7366
7367
7368
7369
7370
7371
7372 <td style="vertical-align: top;"><a name="netcdf_precision"></a><span style="font-weight: bold;">netcdf_precision</span><br>
7373
7374
7375
7376
7377
7378
7379
7380      </td>
7381
7382
7383
7384
7385
7386
7387 <td style="vertical-align: top;">C*20<br>
7388
7389
7390
7391
7392
7393
7394
7395(10)<br>
7396
7397
7398
7399
7400
7401
7402 </td>
7403
7404
7405
7406
7407
7408
7409 <td style="vertical-align: top;"><span style="font-style: italic;">single preci-</span><br style="font-style: italic;">
7410
7411
7412
7413
7414
7415
7416 <span style="font-style: italic;">sion for all</span><br style="font-style: italic;">
7417
7418
7419
7420
7421
7422
7423 <span style="font-style: italic;">output quan-</span><br style="font-style: italic;">
7424
7425
7426
7427
7428
7429
7430 <span style="font-style: italic;">tities</span><br>
7431
7432
7433
7434
7435
7436
7437 </td>
7438
7439
7440
7441
7442
7443
7444
7445      <td style="vertical-align: top;">Defines the accuracy of
7446the NetCDF output.<br>
7447
7448
7449
7450
7451
7452
7453 <br>
7454
7455
7456
7457
7458
7459
7460
7461By default, all NetCDF output data (see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
7462have single precision&nbsp; (4 byte) accuracy. Double precision (8
7463byte) can be choosen alternatively.<br>
7464
7465
7466
7467
7468
7469
7470
7471Accuracy for the different output data (cross sections, 3d-volume data,
7472spectra, etc.) can be set independently.<br>
7473
7474
7475
7476
7477
7478
7479 <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL4'</span>
7480(single precision) or <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL8'</span>
7481(double precision) are the two principally allowed values for <span style="font-weight: bold;">netcdf_precision</span>,
7482where the string <span style="font-style: italic;">'&lt;out&gt;'
7483      </span>can be chosen out of the following list:<br>
7484
7485
7486
7487
7488
7489
7490 <br>
7491
7492
7493
7494
7495
7496
7497
7498     
7499     
7500     
7501     
7502     
7503     
7504      <table style="text-align: left; width: 284px; height: 234px;" border="1" cellpadding="2" cellspacing="2">
7505
7506
7507
7508
7509
7510
7511 <tbody>
7512
7513
7514
7515
7516
7517
7518
7519          <tr>
7520
7521
7522
7523
7524
7525
7526 <td style="vertical-align: top;"><span style="font-style: italic;">'xy'</span><br>
7527
7528
7529
7530
7531
7532
7533 </td>
7534
7535
7536
7537
7538
7539
7540
7541            <td style="vertical-align: top;">horizontal cross section<br>
7542
7543
7544
7545
7546
7547
7548
7549            </td>
7550
7551
7552
7553
7554
7555
7556 </tr>
7557
7558
7559
7560
7561
7562
7563 <tr>
7564
7565
7566
7567
7568
7569
7570 <td style="vertical-align: top;"><span style="font-style: italic;">'xz'</span><br>
7571
7572
7573
7574
7575
7576
7577 </td>
7578
7579
7580
7581
7582
7583
7584
7585            <td style="vertical-align: top;">vertical (xz) cross
7586section<br>
7587
7588
7589
7590
7591
7592
7593 </td>
7594
7595
7596
7597
7598
7599
7600 </tr>
7601
7602
7603
7604
7605
7606
7607 <tr>
7608
7609
7610
7611
7612
7613
7614 <td style="vertical-align: top;"><span style="font-style: italic;">'yz'</span><br>
7615
7616
7617
7618
7619
7620
7621 </td>
7622
7623
7624
7625
7626
7627
7628
7629            <td style="vertical-align: top;">vertical (yz) cross
7630section<br>
7631
7632
7633
7634
7635
7636
7637 </td>
7638
7639
7640
7641
7642
7643
7644 </tr>
7645
7646
7647
7648
7649
7650
7651 <tr>
7652
7653
7654
7655
7656
7657
7658 <td style="vertical-align: top;"><span style="font-style: italic;">'2d'</span><br>
7659
7660
7661
7662
7663
7664
7665 </td>
7666
7667
7668
7669
7670
7671
7672
7673            <td style="vertical-align: top;">all cross sections<br>
7674
7675
7676
7677
7678
7679
7680
7681            </td>
7682
7683
7684
7685
7686
7687
7688 </tr>
7689
7690
7691
7692
7693
7694
7695 <tr>
7696
7697
7698
7699
7700
7701
7702 <td style="vertical-align: top;"><span style="font-style: italic;">'3d'</span><br>
7703
7704
7705
7706
7707
7708
7709 </td>
7710
7711
7712
7713
7714
7715
7716
7717            <td style="vertical-align: top;">volume data<br>
7718
7719
7720
7721
7722
7723
7724 </td>
7725
7726
7727
7728
7729
7730
7731
7732          </tr>
7733
7734
7735
7736
7737
7738
7739 <tr>
7740
7741
7742
7743
7744
7745
7746 <td style="vertical-align: top;"><span style="font-style: italic;">'pr'</span><br>
7747
7748
7749
7750
7751
7752
7753 </td>
7754
7755
7756
7757
7758
7759
7760
7761            <td style="vertical-align: top;">vertical profiles<br>
7762
7763
7764
7765
7766
7767
7768
7769            </td>
7770
7771
7772
7773
7774
7775
7776 </tr>
7777
7778
7779
7780
7781
7782
7783 <tr>
7784
7785
7786
7787
7788
7789
7790 <td style="vertical-align: top;"><span style="font-style: italic;">'ts'</span><br>
7791
7792
7793
7794
7795
7796
7797 </td>
7798
7799
7800
7801
7802
7803
7804
7805            <td style="vertical-align: top;">time series, particle
7806time series<br>
7807
7808
7809
7810
7811
7812
7813 </td>
7814
7815
7816
7817
7818
7819
7820 </tr>
7821
7822
7823
7824
7825
7826
7827 <tr>
7828
7829
7830
7831
7832
7833
7834 <td style="vertical-align: top;"><span style="font-style: italic;">'sp'</span><br>
7835
7836
7837
7838
7839
7840
7841 </td>
7842
7843
7844
7845
7846
7847
7848
7849            <td style="vertical-align: top;">spectra<br>
7850
7851
7852
7853
7854
7855
7856 </td>
7857
7858
7859
7860
7861
7862
7863
7864          </tr>
7865
7866
7867
7868
7869
7870
7871 <tr>
7872
7873
7874
7875
7876
7877
7878 <td style="vertical-align: top;"><span style="font-style: italic;">'prt'</span><br>
7879
7880
7881
7882
7883
7884
7885 </td>
7886
7887
7888
7889
7890
7891
7892
7893            <td style="vertical-align: top;">particles<br>
7894
7895
7896
7897
7898
7899
7900 </td>
7901
7902
7903
7904
7905
7906
7907
7908          </tr>
7909
7910
7911
7912
7913
7914
7915 <tr>
7916
7917
7918
7919
7920
7921
7922 <td style="vertical-align: top;"><span style="font-style: italic;">'all'</span><br>
7923
7924
7925
7926
7927
7928
7929 </td>
7930
7931
7932
7933
7934
7935
7936
7937            <td style="vertical-align: top;">all output quantities<br>
7938
7939
7940
7941
7942
7943
7944
7945            </td>
7946
7947
7948
7949
7950
7951
7952 </tr>
7953
7954
7955
7956
7957
7958
7959 
7960       
7961       
7962       
7963       
7964       
7965       
7966        </tbody> 
7967     
7968     
7969     
7970     
7971     
7972     
7973      </table>
7974
7975
7976
7977
7978
7979
7980 <br>
7981
7982
7983
7984
7985
7986
7987 <span style="font-weight: bold;">Example:</span><br>
7988
7989
7990
7991
7992
7993
7994
7995If all cross section data and the particle data shall be output in
7996double 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>
7997has to be assigned.<br>
7998
7999
8000
8001
8002
8003
8004 </td>
8005
8006
8007
8008
8009
8010
8011 </tr>
8012
8013
8014
8015
8016
8017
8018
8019   
8020
8021
8022
8023
8024
8025
8026 
8027
8028
8029
8030
8031
8032
8033
8034    <tr>
8035
8036
8037
8038
8039
8040
8041 <td style="vertical-align: top;"> 
8042     
8043     
8044     
8045     
8046     
8047     
8048      <p><a name="nsor_ini"></a><b>nsor_ini</b></p>
8049
8050
8051
8052
8053
8054
8055
8056      </td>
8057
8058
8059
8060
8061
8062
8063 <td style="vertical-align: top;">I</td>
8064
8065
8066
8067
8068
8069
8070
8071      <td style="vertical-align: top;"><i>100</i></td>
8072
8073
8074
8075
8076
8077
8078
8079      <td style="vertical-align: top;"> 
8080     
8081     
8082     
8083     
8084     
8085     
8086      <p>Initial number
8087of iterations with the SOR algorithm.&nbsp; </p>
8088
8089
8090
8091
8092
8093
8094 
8095     
8096     
8097     
8098     
8099     
8100     
8101      <p>This
8102parameter is only effective if the SOR algorithm was
8103selected as the pressure solver scheme (<a href="chapter_4.2.html#psolver">psolver</a>
8104= <span style="font-style: italic;">'sor'</span>)
8105and specifies the
8106number of initial iterations of the SOR
8107scheme (at t = 0). The number of subsequent iterations at the following
8108timesteps is determined
8109with the parameter <a href="#nsor">nsor</a>.
8110Usually <b>nsor</b> &lt; <b>nsor_ini</b>,
8111since in each case
8112subsequent calls to <a href="chapter_4.2.html#psolver">psolver</a>
8113use the solution of the previous call as initial value. Suitable
8114test runs should determine whether sufficient convergence of the
8115solution is obtained with the default value and if necessary the value
8116of <b>nsor_ini</b> should be changed.</p>
8117
8118
8119
8120
8121
8122
8123 </td>
8124
8125
8126
8127
8128
8129
8130
8131    </tr>
8132
8133
8134
8135
8136
8137
8138 <tr>
8139
8140
8141
8142
8143
8144
8145 <td style="vertical-align: top;">
8146     
8147     
8148     
8149     
8150     
8151     
8152      <p><a name="nx"></a><b>nx</b></p>
8153
8154
8155
8156
8157
8158
8159
8160      </td>
8161
8162
8163
8164
8165
8166
8167 <td style="vertical-align: top;">I</td>
8168
8169
8170
8171
8172
8173
8174
8175      <td style="vertical-align: top;"><br>
8176
8177
8178
8179
8180
8181
8182 </td>
8183
8184
8185
8186
8187
8188
8189 <td style="vertical-align: top;"> 
8190     
8191     
8192     
8193     
8194     
8195     
8196      <p>Number of grid
8197points in x-direction.&nbsp; </p>
8198
8199
8200
8201
8202
8203
8204 
8205     
8206     
8207     
8208     
8209     
8210     
8211      <p>A value for this
8212parameter must be assigned. Since the lower
8213array bound in PALM
8214starts with i = 0, the actual number of grid points is equal to <b>nx+1</b>.
8215In case of cyclic boundary conditions along x, the domain size is (<b>nx+1</b>)*
8216      <a href="#dx">dx</a>.</p>
8217
8218
8219
8220
8221
8222
8223 
8224     
8225     
8226     
8227     
8228     
8229     
8230      <p>For
8231parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8232= <span style="font-style: italic;">'strict'</span>,
8233      <b>nx+1</b> must
8234be an integral multiple
8235of the processor numbers (see <a href="#npex">npex</a>
8236and <a href="#npey">npey</a>)
8237along x- as well as along y-direction (due to data
8238transposition restrictions).</p>
8239
8240
8241
8242
8243
8244
8245     
8246     
8247     
8248     
8249     
8250     
8251      <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>
8252and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8253
8254
8255
8256
8257
8258
8259 </td>
8260
8261
8262
8263
8264
8265
8266 </tr>
8267
8268
8269
8270
8271
8272
8273 <tr>
8274
8275
8276
8277
8278
8279
8280
8281      <td style="vertical-align: top;"> 
8282     
8283     
8284     
8285     
8286     
8287     
8288      <p><a name="ny"></a><b>ny</b></p>
8289
8290
8291
8292
8293
8294
8295
8296      </td>
8297
8298
8299
8300
8301
8302
8303 <td style="vertical-align: top;">I</td>
8304
8305
8306
8307
8308
8309
8310
8311      <td style="vertical-align: top;"><br>
8312
8313
8314
8315
8316
8317
8318 </td>
8319
8320
8321
8322
8323
8324
8325 <td style="vertical-align: top;"> 
8326     
8327     
8328     
8329     
8330     
8331     
8332      <p>Number of grid
8333points in y-direction.&nbsp; </p>
8334
8335
8336
8337
8338
8339
8340 
8341     
8342     
8343     
8344     
8345     
8346     
8347      <p>A value for this
8348parameter must be assigned. Since the lower
8349array bound in PALM starts with j = 0, the actual number of grid points
8350is equal to <b>ny+1</b>. In case of cyclic boundary
8351conditions along
8352y, the domain size is (<b>ny+1</b>) * <a href="#dy">dy</a>.</p>
8353
8354
8355
8356
8357
8358
8359
8360     
8361     
8362     
8363     
8364     
8365     
8366      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8367= <span style="font-style: italic;">'strict'</span>,
8368      <b>ny+1</b> must
8369be an integral multiple
8370of the processor numbers (see <a href="#npex">npex</a>
8371and <a href="#npey">npey</a>)&nbsp;
8372along y- as well as along x-direction (due to data
8373transposition restrictions).</p>
8374
8375
8376
8377
8378
8379
8380     
8381     
8382     
8383     
8384     
8385     
8386      <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>
8387and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8388
8389
8390
8391
8392
8393
8394 </td>
8395
8396
8397
8398
8399
8400
8401 </tr>
8402
8403
8404
8405
8406
8407
8408 <tr>
8409
8410
8411
8412
8413
8414
8415
8416      <td style="vertical-align: top;"> 
8417     
8418     
8419     
8420     
8421     
8422     
8423      <p><a name="nz"></a><b>nz</b></p>
8424
8425
8426
8427
8428
8429
8430
8431      </td>
8432
8433
8434
8435
8436
8437
8438 <td style="vertical-align: top;">I</td>
8439
8440
8441
8442
8443
8444
8445
8446      <td style="vertical-align: top;"><br>
8447
8448
8449
8450
8451
8452
8453 </td>
8454
8455
8456
8457
8458
8459
8460 <td style="vertical-align: top;"> 
8461     
8462     
8463     
8464     
8465     
8466     
8467      <p>Number of grid
8468points in z-direction.&nbsp; </p>
8469
8470
8471
8472
8473
8474
8475 
8476     
8477     
8478     
8479     
8480     
8481     
8482      <p>A value for this
8483parameter must be assigned. Since the lower
8484array bound in PALM
8485starts with k = 0 and since one additional grid point is added at the
8486top boundary (k = <b>nz+1</b>), the actual number of grid
8487points is <b>nz+2</b>.
8488However, the prognostic equations are only solved up to <b>nz</b>
8489(u,
8490v)
8491or up to <b>nz-1</b> (w, scalar quantities). The top
8492boundary for u
8493and v is at k = <b>nz+1</b> (u, v) while at k = <b>nz</b>
8494for all
8495other quantities.&nbsp; </p>
8496
8497
8498
8499
8500
8501
8502 
8503     
8504     
8505     
8506     
8507     
8508     
8509      <p>For parallel
8510runs,&nbsp; in case of <a href="#grid_matching">grid_matching</a>
8511= <span style="font-style: italic;">'strict'</span>,
8512      <b>nz</b> must
8513be an integral multiple of
8514the number of processors in x-direction (due to data transposition
8515restrictions).</p>
8516
8517
8518
8519
8520
8521
8522 </td>
8523
8524
8525
8526
8527
8528
8529 </tr>
8530
8531
8532
8533
8534
8535
8536 <tr>
8537
8538
8539
8540
8541
8542
8543      <td style="vertical-align: top;"><a name="ocean"></a><span style="font-weight: bold;">ocean</span></td>
8544
8545
8546
8547
8548
8549
8550      <td style="vertical-align: top;">L</td>
8551
8552
8553
8554
8555
8556
8557      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
8558
8559
8560
8561
8562
8563
8564      <td style="vertical-align: top;">Parameter to switch on&nbsp;ocean runs.<br>
8565
8566
8567
8568
8569
8570
8571      <br>
8572
8573
8574
8575
8576
8577
8578By 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>
8579
8580
8581
8582
8583
8584
8585      <br>
8586
8587
8588
8589
8590
8591
8592     
8593     
8594     
8595     
8596     
8597     
8598      <ul>
8599
8600
8601
8602
8603
8604
8605        <li>An additional prognostic equation for salinity is solved.</li>
8606
8607
8608
8609
8610
8611
8612        <li>Potential temperature in buoyancy and stability-related terms is replaced by potential density.</li>
8613
8614
8615
8616
8617
8618
8619        <li>Potential
8620density is calculated from the equation of state for seawater after
8621each timestep, using the algorithm proposed by Jackett et al. (2006, J.
8622Atmos. Oceanic Technol., <span style="font-weight: bold;">23</span>, 1709-1728).<br>
8623
8624
8625
8626
8627
8628
8629So far, only the initial hydrostatic pressure is entered into this equation.</li>
8630
8631
8632
8633
8634
8635
8636        <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>
8637
8638
8639
8640
8641
8642
8643        <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>
8644
8645
8646
8647
8648
8649
8650        <li>Zero salinity flux is used as default boundary condition at the bottom of the sea.</li>
8651
8652
8653
8654
8655
8656
8657        <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>
8658
8659
8660
8661
8662
8663
8664     
8665     
8666     
8667     
8668     
8669     
8670      </ul>
8671
8672
8673
8674
8675
8676
8677      <br>
8678
8679
8680
8681
8682
8683
8684Relevant 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>
8685
8686
8687
8688
8689
8690
8691      <br>
8692
8693
8694
8695
8696
8697
8698Section <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>
8699
8700
8701
8702
8703
8704
8705      <br>
8706
8707
8708
8709
8710
8711
8712      <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>
8713
8714
8715
8716      </td>
8717
8718
8719
8720
8721
8722
8723    </tr>
8724
8725
8726
8727
8728
8729
8730    <tr>
8731
8732
8733
8734
8735
8736
8737 <td style="vertical-align: top;"> 
8738     
8739     
8740     
8741     
8742     
8743     
8744      <p><a name="omega"></a><b>omega</b></p>
8745
8746
8747
8748
8749
8750
8751
8752      </td>
8753
8754
8755
8756
8757
8758
8759 <td style="vertical-align: top;">R</td>
8760
8761
8762
8763
8764
8765
8766
8767      <td style="vertical-align: top;"><i>7.29212E-5</i></td>
8768
8769
8770
8771
8772
8773
8774
8775      <td style="vertical-align: top;"> 
8776     
8777     
8778     
8779     
8780     
8781     
8782      <p>Angular
8783velocity of the rotating system (in rad s<sup>-1</sup>).&nbsp;
8784      </p>
8785
8786
8787
8788
8789
8790
8791 
8792     
8793     
8794     
8795     
8796     
8797     
8798      <p>The angular velocity of the earth is set by
8799default. The
8800values
8801of the Coriolis parameters are calculated as:&nbsp; </p>
8802
8803
8804
8805
8806
8807
8808 
8809     
8810     
8811     
8812     
8813     
8814     
8815      <ul>
8816
8817
8818
8819
8820
8821
8822
8823       
8824       
8825       
8826       
8827       
8828       
8829        <p>f = 2.0 * <b>omega</b> * sin(<a href="#phi">phi</a>)&nbsp;
8830        <br>
8831
8832
8833
8834
8835
8836
8837f* = 2.0 * <b>omega</b> * cos(<a href="#phi">phi</a>)</p>
8838
8839
8840
8841
8842
8843
8844
8845     
8846     
8847     
8848     
8849     
8850     
8851      </ul>
8852
8853
8854
8855
8856
8857
8858 </td>
8859
8860
8861
8862
8863
8864
8865 </tr>
8866
8867
8868
8869
8870
8871
8872 <tr>
8873
8874
8875
8876
8877
8878
8879 <td style="vertical-align: top;"> 
8880     
8881     
8882     
8883     
8884     
8885     
8886      <p><a name="outflow_damping_width"></a><b>outflow_damping_width</b></p>
8887
8888
8889
8890
8891
8892
8893
8894      </td>
8895
8896
8897
8898
8899
8900
8901 <td style="vertical-align: top;">I</td>
8902
8903
8904
8905
8906
8907
8908
8909      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(20,
8910nx/2</span> or <span style="font-style: italic;">ny/2)</span></td>
8911
8912
8913
8914
8915
8916
8917
8918      <td style="vertical-align: top;">Width of
8919the damping range in the vicinity of the outflow (gridpoints).<br>
8920
8921
8922
8923
8924
8925
8926
8927      <br>
8928
8929
8930
8931
8932
8933
8934
8935When using non-cyclic lateral boundaries (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
8936or <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
8937a smoothing has to be applied to the
8938velocity field in the vicinity of the outflow in order to suppress any
8939reflections of outgoing disturbances. This parameter controlls the
8940horizontal range to which the smoothing is applied. The range is given
8941in gridpoints counted from the respective outflow boundary. For further
8942details about the smoothing see parameter <a href="chapter_4.1.html#km_damp_max">km_damp_max</a>,
8943which defines the magnitude of the damping.</td>
8944
8945
8946
8947
8948
8949
8950 </tr>
8951
8952
8953
8954
8955
8956
8957
8958    <tr>
8959
8960
8961
8962
8963
8964
8965 <td style="vertical-align: top;"> 
8966     
8967     
8968     
8969     
8970     
8971     
8972      <p><a name="overshoot_limit_e"></a><b>overshoot_limit_e</b></p>
8973
8974
8975
8976
8977
8978
8979
8980      </td>
8981
8982
8983
8984
8985
8986
8987 <td style="vertical-align: top;">R</td>
8988
8989
8990
8991
8992
8993
8994
8995      <td style="vertical-align: top;"><i>0.0</i></td>
8996
8997
8998
8999
9000
9001
9002
9003      <td style="vertical-align: top;"> 
9004     
9005     
9006     
9007     
9008     
9009     
9010      <p>Allowed limit
9011for the overshooting of subgrid-scale TKE in
9012case that the upstream-spline scheme is switched on (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
9013      </p>
9014
9015
9016
9017
9018