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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
3406
3407      <td style="vertical-align: top;"><a name="cthf"></a><span style="font-weight: bold;">cthf</span></td>
3408
3409      <td style="vertical-align: top;">R</td>
3410
3411      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3412
3413      <td style="vertical-align: top;">Average heat flux that is prescribed at the top of the plant canopy.<br>
3414
3415
3416      <br>
3417
3418
3419If <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>
3420
3421
3422It is assumed that solar radiation penetrates the canopy and warms the
3423foliage which, in turn, warms the air in contact with it. <br>
3424
3425
3426Note: Instead of using the value prescribed by <a href="#surface_heatflux">surface_heatflux</a>,
3427the near surface heat flux is determined from an exponential function
3428that is dependent on the cumulative leaf_area_index (Shaw and Schumann
3429(1992, Boundary Layer Meteorol., 61, 47-64)).</td>
3430
3431    </tr>
3432      <td style="vertical-align: top;"><a name="coupling_start_time"></a><span style="font-weight: bold;">coupling_start_time</span></td>
3433
3434      <td style="vertical-align: top;">R</td>
3435
3436      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3437
3438      <td style="vertical-align: top;">Simulation time of precursor run.
3439      <br>
3440      <br>
3441         Sets the time period a precursor run shall run uncoupled. This parameter is used to set up the precursor run control for atmosphere-ocean-coupled runs. It has to be set individually to the atmospheric / oceanic precursor run. The time in the data output will show negative values during the precursor run. See documentation  for further information.
3442     
3443      </td>
3444
3445    </tr>
3446    <tr>
3447
3448
3449
3450
3451
3452
3453 <td style="vertical-align: top;"> 
3454     
3455     
3456     
3457     
3458     
3459     
3460      <p><a name="cut_spline_overshoot"></a><b>cut_spline_overshoot</b></p>
3461
3462
3463
3464
3465
3466
3467
3468      </td>
3469
3470
3471
3472
3473
3474
3475 <td style="vertical-align: top;">L</td>
3476
3477
3478
3479
3480
3481
3482
3483      <td style="vertical-align: top;"><span style="font-style: italic;">.T.</span></td>
3484
3485
3486
3487
3488
3489
3490 <td style="vertical-align: top;"> 
3491     
3492     
3493     
3494     
3495     
3496     
3497      <p>Cuts off of
3498so-called overshoots, which can occur with the
3499upstream-spline scheme.&nbsp; </p>
3500
3501
3502
3503
3504
3505
3506 
3507     
3508     
3509     
3510     
3511     
3512     
3513      <p><font color="#000000">The cubic splines tend to overshoot in
3514case of discontinuous changes of variables between neighbouring grid
3515points.</font><font color="#ff0000"> </font><font color="#000000">This
3516may lead to errors in calculating the advection tendency.</font>
3517Choice
3518of <b>cut_spline_overshoot</b> = <i>.TRUE.</i>
3519(switched on by
3520default)
3521allows variable values not to exceed an interval defined by the
3522respective adjacent grid points. This interval can be adjusted
3523seperately for every prognostic variable (see initialization parameters
3524      <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>,
3525etc.). This might be necessary in case that the
3526default interval has a non-tolerable effect on the model
3527results.&nbsp; </p>
3528
3529
3530
3531
3532
3533
3534 
3535     
3536     
3537     
3538     
3539     
3540     
3541      <p>Overshoots may also be removed
3542using the parameters <a href="#ups_limit_e">ups_limit_e</a>,
3543      <a href="#ups_limit_pt">ups_limit_pt</a>,
3544etc. as well as by applying a long-filter (see <a href="#long_filter_factor">long_filter_factor</a>).</p>
3545
3546
3547
3548
3549
3550
3551
3552      </td>
3553
3554
3555
3556
3557
3558
3559 </tr>
3560
3561
3562
3563
3564
3565
3566 <tr>
3567
3568
3569
3570
3571
3572
3573 <td style="vertical-align: top;"> 
3574     
3575     
3576     
3577     
3578     
3579     
3580      <p><a name="damp_level_1d"></a><b>damp_level_1d</b></p>
3581
3582
3583
3584
3585
3586
3587
3588      </td>
3589
3590
3591
3592
3593
3594
3595 <td style="vertical-align: top;">R</td>
3596
3597
3598
3599
3600
3601
3602
3603      <td style="vertical-align: top;"><span style="font-style: italic;">zu(nz+1)</span></td>
3604
3605
3606
3607
3608
3609
3610
3611      <td style="vertical-align: top;"> 
3612     
3613     
3614     
3615     
3616     
3617     
3618      <p>Height where
3619the damping layer begins in the 1d-model
3620(in m).&nbsp; </p>
3621
3622
3623
3624
3625
3626
3627 
3628     
3629     
3630     
3631     
3632     
3633     
3634      <p>This parameter is used to
3635switch on a damping layer for the
36361d-model, which is generally needed for the damping of inertia
3637oscillations. Damping is done by gradually increasing the value
3638of the eddy diffusivities about 10% per vertical grid level
3639(starting with the value at the height given by <b>damp_level_1d</b>,
3640or possibly from the next grid pint above), i.e. K<sub>m</sub>(k+1)
3641=
36421.1 * K<sub>m</sub>(k).
3643The values of K<sub>m</sub> are limited to 10 m**2/s at
3644maximum.&nbsp; <br>
3645
3646
3647
3648
3649
3650
3651
3652This parameter only comes into effect if the 1d-model is switched on
3653for
3654the initialization of the 3d-model using <a href="#initializing_actions">initializing_actions</a>
3655= <span style="font-style: italic;">'set_1d-model_profiles'</span>.
3656      <br>
3657
3658
3659
3660
3661
3662
3663 </p>
3664
3665
3666
3667
3668
3669
3670 </td>
3671
3672
3673
3674
3675
3676
3677 </tr>
3678
3679
3680
3681
3682
3683
3684 <tr>
3685
3686
3687
3688
3689
3690
3691 <td style="vertical-align: top;"><a name="dissipation_1d"></a><span style="font-weight: bold;">dissipation_1d</span><br>
3692
3693
3694
3695
3696
3697
3698
3699      </td>
3700
3701
3702
3703
3704
3705
3706 <td style="vertical-align: top;">C*20<br>
3707
3708
3709
3710
3711
3712
3713
3714      </td>
3715
3716
3717
3718
3719
3720
3721 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
3722
3723
3724
3725
3726
3727
3728 <span style="font-style: italic;">model'</span><br>
3729
3730
3731
3732
3733
3734
3735 </td>
3736
3737
3738
3739
3740
3741
3742
3743      <td style="vertical-align: top;">Calculation method for
3744the energy dissipation term in the TKE equation of the 1d-model.<br>
3745
3746
3747
3748
3749
3750
3751
3752      <br>
3753
3754
3755
3756
3757
3758
3759
3760By default the dissipation is calculated as in the 3d-model using diss
3761= (0.19 + 0.74 * l / l_grid) * e**1.5 / l.<br>
3762
3763
3764
3765
3766
3767
3768 <br>
3769
3770
3771
3772
3773
3774
3775
3776Setting <span style="font-weight: bold;">dissipation_1d</span>
3777= <span style="font-style: italic;">'detering'</span>
3778forces the dissipation to be calculated as diss = 0.064 * e**1.5 / l.<br>
3779
3780
3781
3782
3783
3784
3785
3786      </td>
3787
3788
3789
3790
3791
3792
3793 </tr>
3794    <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
3795parameter is used to switch on/off an external pressure gradient as
3796driving force. The external pressure gradient is controlled by the
3797parameters <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
3798limit 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
3799must hold the condition zu(0) &lt;= <b>dp_level_b</b>
3800&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
3801that there is no upper limit of the vertical range because the external
3802pressure 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>
3803
3804
3805
3806
3807
3808
3809    <tr>
3810
3811      <td style="vertical-align: top;"><a name="drag_coefficient"></a><span style="font-weight: bold;">drag_coefficient</span></td>
3812
3813      <td style="vertical-align: top;">R</td>
3814
3815      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
3816
3817      <td style="vertical-align: top;">Drag coefficient used in the plant canopy model.<br>
3818
3819      <br>
3820
3821This 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>
3822
3823    </tr>
3824
3825    <tr>
3826
3827
3828
3829
3830
3831
3832 <td style="vertical-align: top;"> 
3833     
3834     
3835     
3836     
3837     
3838     
3839      <p><a name="dt"></a><b>dt</b></p>
3840
3841
3842
3843
3844
3845
3846 </td>
3847
3848
3849
3850
3851
3852
3853
3854      <td style="vertical-align: top;">R</td>
3855
3856
3857
3858
3859
3860
3861 <td style="vertical-align: top;"><span style="font-style: italic;">variable</span></td>
3862
3863
3864
3865
3866
3867
3868
3869      <td style="vertical-align: top;"> 
3870     
3871     
3872     
3873     
3874     
3875     
3876      <p>Time step for
3877the 3d-model (in s).&nbsp; </p>
3878
3879
3880
3881
3882
3883
3884 
3885     
3886     
3887     
3888     
3889     
3890     
3891      <p>By default, (i.e.
3892if a Runge-Kutta scheme is used, see <a href="#timestep_scheme">timestep_scheme</a>)
3893the value of the time step is calculating after each time step
3894(following the time step criteria) and
3895used for the next step.</p>
3896
3897
3898
3899
3900
3901
3902 
3903     
3904     
3905     
3906     
3907     
3908     
3909      <p>If the user assigns <b>dt</b>
3910a value, then the time step is
3911fixed to this value throughout the whole run (whether it fulfills the
3912time step
3913criteria or not). However, changes are allowed for restart runs,
3914because <b>dt</b> can also be used as a <a href="chapter_4.2.html#dt_laufparameter">run
3915parameter</a>.&nbsp; </p>
3916
3917
3918
3919
3920
3921
3922 
3923     
3924     
3925     
3926     
3927     
3928     
3929      <p>In case that the
3930calculated time step meets the condition<br>
3931
3932
3933
3934
3935
3936
3937 </p>
3938
3939
3940
3941
3942
3943
3944 
3945     
3946     
3947     
3948     
3949     
3950     
3951      <ul>
3952
3953
3954
3955
3956
3957
3958
3959       
3960       
3961       
3962       
3963       
3964       
3965        <p><b>dt</b> &lt; 0.00001 * <a href="chapter_4.2.html#dt_max">dt_max</a> (with dt_max
3966= 20.0)</p>
3967
3968
3969
3970
3971
3972
3973 
3974     
3975     
3976     
3977     
3978     
3979     
3980      </ul>
3981
3982
3983
3984
3985
3986
3987 
3988     
3989     
3990     
3991     
3992     
3993     
3994      <p>the simulation will be
3995aborted. Such situations usually arise
3996in case of any numerical problem / instability which causes a
3997non-realistic increase of the wind speed.&nbsp; </p>
3998
3999
4000
4001
4002
4003
4004 
4005     
4006     
4007     
4008     
4009     
4010     
4011      <p>A
4012small time step due to a large mean horizontal windspeed
4013speed may be enlarged by using a coordinate transformation (see <a href="#galilei_transformation">galilei_transformation</a>),
4014in order to spare CPU time.<br>
4015
4016
4017
4018
4019
4020
4021 </p>
4022
4023
4024
4025
4026
4027
4028 
4029     
4030     
4031     
4032     
4033     
4034     
4035      <p>If the
4036leapfrog timestep scheme is used (see <a href="#timestep_scheme">timestep_scheme</a>)
4037a temporary time step value dt_new is calculated first, with dt_new = <a href="chapter_4.2.html#fcl_factor">cfl_factor</a>
4038* dt_crit where dt_crit is the maximum timestep allowed by the CFL and
4039diffusion condition. Next it is examined whether dt_new exceeds or
4040falls below the
4041value of the previous timestep by at
4042least +5 % / -2%. If it is smaller, <span style="font-weight: bold;">dt</span>
4043= dt_new is immediately used for the next timestep. If it is larger,
4044then <span style="font-weight: bold;">dt </span>=
40451.02 * dt_prev
4046(previous timestep) is used as the new timestep, however the time
4047step is only increased if the last change of the time step is dated
4048back at
4049least 30 iterations. If dt_new is located in the interval mentioned
4050above, then dt
4051does not change at all. By doing so, permanent time step changes as
4052well as large
4053sudden changes (increases) in the time step are avoided.</p>
4054
4055
4056
4057
4058
4059
4060 </td>
4061
4062
4063
4064
4065
4066
4067
4068    </tr>
4069
4070
4071
4072
4073
4074
4075 <tr>
4076
4077
4078
4079
4080
4081
4082 <td style="vertical-align: top;">
4083     
4084     
4085     
4086     
4087     
4088     
4089      <p><a name="dt_pr_1d"></a><b>dt_pr_1d</b></p>
4090
4091
4092
4093
4094
4095
4096
4097      </td>
4098
4099
4100
4101
4102
4103
4104 <td style="vertical-align: top;">R</td>
4105
4106
4107
4108
4109
4110
4111
4112      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4113
4114
4115
4116
4117
4118
4119
4120      <td style="vertical-align: top;"> 
4121     
4122     
4123     
4124     
4125     
4126     
4127      <p>Temporal
4128interval of vertical profile output of the 1D-model
4129(in s).&nbsp; </p>
4130
4131
4132
4133
4134
4135
4136 
4137     
4138     
4139     
4140     
4141     
4142     
4143      <p>Data are written in ASCII
4144format to file <a href="chapter_3.4.html#LIST_PROFIL_1D">LIST_PROFIL_1D</a>.
4145This parameter is only in effect if the 1d-model has been switched on
4146for the
4147initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4148= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4149
4150
4151
4152
4153
4154
4155
4156      </td>
4157
4158
4159
4160
4161
4162
4163 </tr>
4164
4165
4166
4167
4168
4169
4170 <tr>
4171
4172
4173
4174
4175
4176
4177 <td style="vertical-align: top;"> 
4178     
4179     
4180     
4181     
4182     
4183     
4184      <p><a name="dt_run_control_1d"></a><b>dt_run_control_1d</b></p>
4185
4186
4187
4188
4189
4190
4191
4192      </td>
4193
4194
4195
4196
4197
4198
4199 <td style="vertical-align: top;">R</td>
4200
4201
4202
4203
4204
4205
4206
4207      <td style="vertical-align: top;"><span style="font-style: italic;">60.0</span></td>
4208
4209
4210
4211
4212
4213
4214 <td style="vertical-align: top;"> 
4215     
4216     
4217     
4218     
4219     
4220     
4221      <p>Temporal interval of
4222runtime control output of the 1d-model
4223(in s).&nbsp; </p>
4224
4225
4226
4227
4228
4229
4230 
4231     
4232     
4233     
4234     
4235     
4236     
4237      <p>Data are written in ASCII
4238format to file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.
4239This parameter is only in effect if the 1d-model is switched on for the
4240initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
4241= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
4242
4243
4244
4245
4246
4247
4248
4249      </td>
4250
4251
4252
4253
4254
4255
4256 </tr>
4257
4258
4259
4260
4261
4262
4263 <tr>
4264
4265
4266
4267
4268
4269
4270 <td style="vertical-align: top;"> 
4271     
4272     
4273     
4274     
4275     
4276     
4277      <p><a name="dx"></a><b>dx</b></p>
4278
4279
4280
4281
4282
4283
4284
4285      </td>
4286
4287
4288
4289
4290
4291
4292 <td style="vertical-align: top;">R</td>
4293
4294
4295
4296
4297
4298
4299
4300      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4301
4302
4303
4304
4305
4306
4307 <td style="vertical-align: top;"> 
4308     
4309     
4310     
4311     
4312     
4313     
4314      <p>Horizontal grid
4315spacing along the x-direction (in m).&nbsp; </p>
4316
4317
4318
4319
4320
4321
4322 
4323     
4324     
4325     
4326     
4327     
4328     
4329      <p>Along
4330x-direction only a constant grid spacing is allowed.</p>
4331
4332
4333
4334
4335
4336
4337     
4338     
4339     
4340     
4341     
4342     
4343      <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>
4344and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4345
4346
4347
4348
4349
4350
4351 </td>
4352
4353
4354
4355
4356
4357
4358
4359    </tr>
4360
4361
4362
4363
4364
4365
4366 <tr>
4367
4368
4369
4370
4371
4372
4373 <td style="vertical-align: top;">
4374     
4375     
4376     
4377     
4378     
4379     
4380      <p><a name="dy"></a><b>dy</b></p>
4381
4382
4383
4384
4385
4386
4387
4388      </td>
4389
4390
4391
4392
4393
4394
4395 <td style="vertical-align: top;">R</td>
4396
4397
4398
4399
4400
4401
4402
4403      <td style="vertical-align: top;"><span style="font-style: italic;">1.0</span></td>
4404
4405
4406
4407
4408
4409
4410 <td style="vertical-align: top;"> 
4411     
4412     
4413     
4414     
4415     
4416     
4417      <p>Horizontal grid
4418spacing along the y-direction (in m).&nbsp; </p>
4419
4420
4421
4422
4423
4424
4425 
4426     
4427     
4428     
4429     
4430     
4431     
4432      <p>Along y-direction only a constant grid spacing is allowed.</p>
4433
4434
4435
4436
4437
4438
4439     
4440     
4441     
4442     
4443     
4444     
4445      <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>
4446and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
4447
4448
4449
4450
4451
4452
4453 </td>
4454
4455
4456
4457
4458
4459
4460
4461    </tr>
4462
4463
4464
4465
4466
4467
4468 <tr>
4469
4470
4471
4472
4473
4474
4475 <td style="vertical-align: top;">
4476     
4477     
4478     
4479     
4480     
4481     
4482      <p><a name="dz"></a><b>dz</b></p>
4483
4484
4485
4486
4487
4488
4489
4490      </td>
4491
4492
4493
4494
4495
4496
4497 <td style="vertical-align: top;">R</td>
4498
4499
4500
4501
4502
4503
4504
4505      <td style="vertical-align: top;"><br>
4506
4507
4508
4509
4510
4511
4512 </td>
4513
4514
4515
4516
4517
4518
4519 <td style="vertical-align: top;"> 
4520     
4521     
4522     
4523     
4524     
4525     
4526      <p>Vertical grid
4527spacing (in m).&nbsp; </p>
4528
4529
4530
4531
4532
4533
4534 
4535     
4536     
4537     
4538     
4539     
4540     
4541      <p>This parameter must be
4542assigned by the user, because no
4543default value is given.<br>
4544
4545
4546
4547
4548
4549
4550 </p>
4551
4552
4553
4554
4555
4556
4557 
4558     
4559     
4560     
4561     
4562     
4563     
4564      <p>By default, the
4565model uses constant grid spacing along z-direction, but it can be
4566stretched using the parameters <a href="#dz_stretch_level">dz_stretch_level</a>
4567and <a href="#dz_stretch_factor">dz_stretch_factor</a>.
4568In case of stretching, a maximum allowed grid spacing can be given by <a href="#dz_max">dz_max</a>.<br>
4569
4570
4571
4572
4573
4574
4575 </p>
4576
4577
4578
4579
4580
4581
4582 
4583     
4584     
4585     
4586     
4587     
4588     
4589      <p>Assuming
4590a constant <span style="font-weight: bold;">dz</span>,
4591the scalar levels (zu) are calculated directly by:&nbsp; </p>
4592
4593
4594
4595
4596
4597
4598
4599     
4600     
4601     
4602     
4603     
4604     
4605      <ul>
4606
4607
4608
4609
4610
4611
4612 
4613       
4614       
4615       
4616       
4617       
4618       
4619        <p>zu(0) = - dz * 0.5&nbsp; <br>
4620
4621
4622
4623
4624
4625
4626
4627zu(1) = dz * 0.5</p>
4628
4629
4630
4631
4632
4633
4634 
4635     
4636     
4637     
4638     
4639     
4640     
4641      </ul>
4642
4643
4644
4645
4646
4647
4648 
4649     
4650     
4651     
4652     
4653     
4654     
4655      <p>The w-levels lie
4656half between them:&nbsp; </p>
4657
4658
4659
4660
4661
4662
4663 
4664     
4665     
4666     
4667     
4668     
4669     
4670      <ul>
4671
4672
4673
4674
4675
4676
4677 
4678       
4679       
4680       
4681       
4682       
4683       
4684        <p>zw(k) =
4685( zu(k) + zu(k+1) ) * 0.5</p>
4686
4687
4688
4689
4690
4691
4692 
4693     
4694     
4695     
4696     
4697     
4698     
4699      </ul>
4700
4701
4702
4703
4704
4705
4706 </td>
4707
4708
4709
4710
4711
4712
4713 </tr>
4714
4715
4716
4717
4718
4719
4720
4721    <tr>
4722
4723
4724
4725
4726
4727
4728      <td style="vertical-align: top;"><a name="dz_max"></a><span style="font-weight: bold;">dz_max</span></td>
4729
4730
4731
4732
4733
4734
4735      <td style="vertical-align: top;">R</td>
4736
4737
4738
4739
4740
4741
4742      <td style="vertical-align: top;"><span style="font-style: italic;">9999999.9</span></td>
4743
4744
4745
4746
4747
4748
4749      <td style="vertical-align: top;">Allowed maximum vertical grid
4750spacing (in m).<br>
4751
4752
4753
4754
4755
4756
4757      <br>
4758
4759
4760
4761
4762
4763
4764If the vertical grid is stretched
4765(see <a href="#dz_stretch_factor">dz_stretch_factor</a>
4766and <a href="#dz_stretch_level">dz_stretch_level</a>),
4767      <span style="font-weight: bold;">dz_max</span> can
4768be used to limit the vertical grid spacing.</td>
4769
4770
4771
4772
4773
4774
4775    </tr>
4776
4777
4778
4779
4780
4781
4782    <tr>
4783
4784
4785
4786
4787
4788
4789
4790      <td style="vertical-align: top;"> 
4791     
4792     
4793     
4794     
4795     
4796     
4797      <p><a name="dz_stretch_factor"></a><b>dz_stretch_factor</b></p>
4798
4799
4800
4801
4802
4803
4804
4805      </td>
4806
4807
4808
4809
4810
4811
4812 <td style="vertical-align: top;">R</td>
4813
4814
4815
4816
4817
4818
4819
4820      <td style="vertical-align: top;"><span style="font-style: italic;">1.08</span></td>
4821
4822
4823
4824
4825
4826
4827 <td style="vertical-align: top;"> 
4828     
4829     
4830     
4831     
4832     
4833     
4834      <p>Stretch factor for a
4835vertically stretched grid (see <a href="#dz_stretch_level">dz_stretch_level</a>).&nbsp;
4836      </p>
4837
4838
4839
4840
4841
4842
4843 
4844     
4845     
4846     
4847     
4848     
4849     
4850      <p>The stretch factor should not exceed a value of
4851approx. 1.10 -
48521.12, otherwise the discretization errors due to the stretched grid not
4853negligible any more. (refer Kalnay de Rivas)</p>
4854
4855
4856
4857
4858
4859
4860 </td>
4861
4862
4863
4864
4865
4866
4867 </tr>
4868
4869
4870
4871
4872
4873
4874
4875    <tr>
4876
4877
4878
4879
4880
4881
4882 <td style="vertical-align: top;"> 
4883     
4884     
4885     
4886     
4887     
4888     
4889      <p><a name="dz_stretch_level"></a><b>dz_stretch_level</b></p>
4890
4891
4892
4893
4894
4895
4896
4897      </td>
4898
4899
4900
4901
4902
4903
4904 <td style="vertical-align: top;">R</td>
4905
4906
4907
4908
4909
4910
4911
4912      <td style="vertical-align: top;"><span style="font-style: italic;">100000.0</span><br>
4913
4914
4915
4916
4917
4918
4919 </td>
4920
4921
4922
4923
4924
4925
4926
4927      <td style="vertical-align: top;"> 
4928     
4929     
4930     
4931     
4932     
4933     
4934      <p>Height level
4935above/below which the grid is to be stretched
4936vertically (in m).&nbsp; </p>
4937
4938
4939
4940
4941
4942
4943 
4944     
4945     
4946     
4947     
4948     
4949     
4950      <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
4951vertically. The vertical grid
4952spacings <a href="#dz">dz</a>
4953above this level are calculated as&nbsp; </p>
4954
4955
4956
4957
4958
4959
4960 
4961     
4962     
4963     
4964     
4965     
4966     
4967      <ul>
4968
4969
4970
4971
4972
4973
4974 
4975       
4976       
4977       
4978       
4979       
4980       
4981        <p><b>dz</b>(k+1)
4982= <b>dz</b>(k) * <a href="#dz_stretch_factor">dz_stretch_factor</a></p>
4983
4984
4985
4986
4987
4988
4989
4990     
4991     
4992     
4993     
4994     
4995     
4996      </ul>
4997
4998
4999
5000
5001
5002
5003 
5004     
5005     
5006     
5007     
5008     
5009     
5010      <p>and used as spacings for the scalar levels (zu).
5011The
5012w-levels are then defined as:&nbsp; </p>
5013
5014
5015
5016
5017
5018
5019 
5020     
5021     
5022     
5023     
5024     
5025     
5026      <ul>
5027
5028
5029
5030
5031
5032
5033 
5034       
5035       
5036       
5037       
5038       
5039       
5040        <p>zw(k)
5041= ( zu(k) + zu(k+1) ) * 0.5.
5042
5043 
5044     
5045      </p>
5046
5047
5048
5049
5050     
5051     
5052     
5053     
5054      </ul>
5055
5056
5057
5058
5059     
5060     
5061     
5062     
5063      <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
5064vertically. The vertical grid
5065spacings <a href="chapter_4.1.html#dz">dz</a> below this level are calculated correspondingly as
5066
5067 
5068     
5069      </p>
5070
5071
5072
5073
5074     
5075     
5076     
5077     
5078      <ul>
5079
5080
5081
5082
5083       
5084       
5085       
5086       
5087        <p><b>dz</b>(k-1)
5088= <b>dz</b>(k) * <a href="chapter_4.1.html#dz_stretch_factor">dz_stretch_factor</a>.</p>
5089
5090
5091
5092
5093     
5094     
5095     
5096     
5097      </ul>
5098
5099
5100
5101
5102
5103
5104 </td>
5105
5106
5107
5108
5109
5110
5111 </tr>
5112
5113
5114
5115
5116
5117
5118
5119    <tr>
5120
5121
5122
5123
5124
5125      <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_init"></a>e_init</span></td>
5126
5127
5128
5129
5130
5131      <td style="vertical-align: top;">R</td>
5132
5133
5134
5135
5136
5137      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5138
5139
5140
5141
5142
5143      <td>Initial subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5144
5145
5146
5147
5148
5149
5150
5151      <br>
5152
5153
5154
5155
5156
5157
5158This
5159option 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>
5160
5161
5162
5163
5164
5165    </tr>
5166
5167
5168
5169
5170
5171    <tr>
5172
5173
5174
5175
5176
5177
5178 <td style="vertical-align: top;"><span style="font-weight: bold;"><a name="e_min"></a>e_min</span></td>
5179
5180
5181
5182
5183
5184
5185
5186      <td style="vertical-align: top;">R</td>
5187
5188
5189
5190
5191
5192
5193 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
5194
5195
5196
5197
5198
5199
5200 <td>Minimum
5201subgrid-scale TKE in m<sup>2</sup>s<sup>-2</sup>.<br>
5202
5203
5204
5205
5206
5207
5208
5209      <br>
5210
5211
5212
5213
5214
5215
5216This
5217option&nbsp;adds artificial viscosity to the flow by ensuring that
5218the
5219subgrid-scale TKE does not fall below the minimum threshold <span style="font-weight: bold;">e_min</span>.</td>
5220
5221
5222
5223
5224
5225
5226 </tr>
5227
5228
5229
5230
5231
5232
5233
5234    <tr>
5235
5236
5237
5238
5239
5240
5241 <td style="vertical-align: top;"> 
5242     
5243     
5244     
5245     
5246     
5247     
5248      <p><a name="end_time_1d"></a><b>end_time_1d</b></p>
5249
5250
5251
5252
5253
5254
5255
5256      </td>
5257
5258
5259
5260
5261
5262
5263 <td style="vertical-align: top;">R</td>
5264
5265
5266
5267
5268
5269
5270
5271      <td style="vertical-align: top;"><span style="font-style: italic;">864000.0</span><br>
5272
5273
5274
5275
5276
5277
5278 </td>
5279
5280
5281
5282
5283
5284
5285
5286      <td style="vertical-align: top;"> 
5287     
5288     
5289     
5290     
5291     
5292     
5293      <p>Time to be
5294simulated for the 1d-model (in s).&nbsp; </p>
5295
5296
5297
5298
5299
5300
5301 
5302     
5303     
5304     
5305     
5306     
5307     
5308      <p>The
5309default value corresponds to a simulated time of 10 days.
5310Usually, after such a period the inertia oscillations have completely
5311decayed and the solution of the 1d-model can be regarded as stationary
5312(see <a href="#damp_level_1d">damp_level_1d</a>).
5313This parameter is only in effect if the 1d-model is switched on for the
5314initialization of the 3d-model with <a href="#initializing_actions">initializing_actions</a>
5315= <span style="font-style: italic;">'set_1d-model_profiles'</span>.</p>
5316
5317
5318
5319
5320
5321
5322
5323      </td>
5324
5325
5326
5327
5328
5329
5330 </tr>
5331
5332
5333
5334
5335
5336
5337 <tr>
5338
5339
5340
5341
5342
5343
5344 <td style="vertical-align: top;"> 
5345     
5346     
5347     
5348     
5349     
5350     
5351      <p><a name="fft_method"></a><b>fft_method</b></p>
5352
5353
5354
5355
5356
5357
5358
5359      </td>
5360
5361
5362
5363
5364
5365
5366 <td style="vertical-align: top;">C * 20</td>
5367
5368
5369
5370
5371
5372
5373
5374      <td style="vertical-align: top;"><span style="font-style: italic;">'system-</span><br style="font-style: italic;">
5375
5376
5377
5378
5379
5380
5381 <span style="font-style: italic;">specific'</span></td>
5382
5383
5384
5385
5386
5387
5388
5389      <td style="vertical-align: top;"> 
5390     
5391     
5392     
5393     
5394     
5395     
5396      <p>FFT-method to
5397be used.<br>
5398
5399
5400
5401
5402
5403
5404 </p>
5405
5406
5407
5408
5409
5410
5411 
5412     
5413     
5414     
5415     
5416     
5417     
5418      <p><br>
5419
5420
5421
5422
5423
5424
5425
5426The fast fourier transformation (FFT) is used for solving the
5427perturbation pressure equation with a direct method (see <a href="chapter_4.2.html#psolver">psolver</a>)
5428and for calculating power spectra (see optional software packages,
5429section <a href="chapter_4.2.html#spectra_package">4.2</a>).</p>
5430
5431
5432
5433
5434
5435
5436
5437     
5438     
5439     
5440     
5441     
5442     
5443      <p><br>
5444
5445
5446
5447
5448
5449
5450
5451By default, system-specific, optimized routines from external
5452vendor libraries are used. However, these are available only on certain
5453computers and there are more or less severe restrictions concerning the
5454number of gridpoints to be used with them.<br>
5455
5456
5457
5458
5459
5460
5461 </p>
5462
5463
5464
5465
5466
5467
5468 
5469     
5470     
5471     
5472     
5473     
5474     
5475      <p>There
5476are two other PALM internal methods available on every
5477machine (their respective source code is part of the PALM source code):</p>
5478
5479
5480
5481
5482
5483
5484
5485     
5486     
5487     
5488     
5489     
5490     
5491      <p>1.: The <span style="font-weight: bold;">Temperton</span>-method
5492from Clive Temperton (ECWMF) which is computationally very fast and
5493switched on with <b>fft_method</b> = <span style="font-style: italic;">'temperton-algorithm'</span>.
5494The number of horizontal gridpoints (nx+1, ny+1) to be used with this
5495method must be composed of prime factors 2, 3 and 5.<br>
5496
5497
5498
5499
5500
5501
5502 </p>
5503
5504
5505
5506
5507
5508
5509
55102.: The <span style="font-weight: bold;">Singleton</span>-method
5511which is very slow but has no restrictions concerning the number of
5512gridpoints to be used with, switched on with <b>fft_method</b>
5513= <span style="font-style: italic;">'singleton-algorithm'</span>.
5514      </td>
5515
5516
5517
5518
5519
5520
5521 </tr>
5522
5523
5524
5525
5526
5527
5528 <tr>
5529
5530
5531
5532
5533
5534
5535 <td style="vertical-align: top;"> 
5536     
5537     
5538     
5539     
5540     
5541     
5542      <p><a name="galilei_transformation"></a><b>galilei_transformation</b></p>
5543
5544
5545
5546
5547
5548
5549
5550      </td>
5551
5552
5553
5554
5555
5556
5557 <td style="vertical-align: top;">L</td>
5558
5559
5560
5561
5562
5563
5564
5565      <td style="vertical-align: top;"><i>.F.</i></td>
5566
5567
5568
5569
5570
5571
5572
5573      <td style="vertical-align: top;">Application of a
5574Galilei-transformation to the
5575coordinate
5576system of the model.<br>
5577
5578
5579
5580
5581
5582
5583     
5584     
5585     
5586     
5587     
5588     
5589      <p>With <b>galilei_transformation</b>
5590= <i>.T.,</i> a so-called
5591Galilei-transformation is switched on which ensures that the coordinate
5592system of the model is moved along with the geostrophical wind.
5593Alternatively, the model domain can be moved along with the averaged
5594horizontal wind (see <a href="#use_ug_for_galilei_tr">use_ug_for_galilei_tr</a>,
5595this can and will naturally change in time). With this method,
5596numerical inaccuracies of the Piascek - Williams - scheme (concerns in
5597particular the momentum advection) are minimized. Beyond that, in the
5598majority of cases the lower relative velocities in the moved system
5599permit a larger time step (<a href="#dt">dt</a>).
5600Switching the transformation on is only worthwhile if the geostrophical
5601wind (ug, vg)
5602and the averaged horizontal wind clearly deviate from the value 0. In
5603each case, the distance the coordinate system has been moved is written
5604to the file <a href="chapter_3.4.html#RUN_CONTROL">RUN_CONTROL</a>.&nbsp;
5605      </p>
5606
5607
5608
5609
5610
5611
5612 
5613     
5614     
5615     
5616     
5617     
5618     
5619      <p>Non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
5620and <a href="#bc_ns">bc_ns</a>), the specification
5621of a gestrophic
5622wind that is not constant with height
5623as well as e.g. stationary inhomogeneities at the bottom boundary do
5624not allow the use of this transformation.</p>
5625
5626
5627
5628
5629
5630
5631 </td>
5632
5633
5634
5635
5636
5637
5638 </tr>
5639
5640
5641
5642
5643
5644
5645
5646    <tr>
5647
5648
5649
5650
5651
5652
5653 <td style="vertical-align: top;"> 
5654     
5655     
5656     
5657     
5658     
5659     
5660      <p><a name="grid_matching"></a><b>grid_matching</b></p>
5661
5662
5663
5664
5665
5666
5667
5668      </td>
5669
5670
5671
5672
5673
5674
5675 <td style="vertical-align: top;">C * 6</td>
5676
5677
5678
5679
5680
5681
5682
5683      <td style="vertical-align: top;"><span style="font-style: italic;">'strict'</span></td>
5684
5685
5686
5687
5688
5689
5690 <td style="vertical-align: top;">Variable to adjust the
5691subdomain
5692sizes in parallel runs.<br>
5693
5694
5695
5696
5697
5698
5699 <br>
5700
5701
5702
5703
5704
5705
5706
5707For <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>,
5708the subdomains are forced to have an identical
5709size on all processors. In this case the processor numbers in the
5710respective directions of the virtual processor net must fulfill certain
5711divisor conditions concerning the grid point numbers in the three
5712directions (see <a href="#nx">nx</a>, <a href="#ny">ny</a>
5713and <a href="#nz">nz</a>).
5714Advantage of this method is that all PEs bear the same computational
5715load.<br>
5716
5717
5718
5719
5720
5721
5722 <br>
5723
5724
5725
5726
5727
5728
5729
5730There is no such restriction by default, because then smaller
5731subdomains are allowed on those processors which
5732form the right and/or north boundary of the virtual processor grid. On
5733all other processors the subdomains are of same size. Whether smaller
5734subdomains are actually used, depends on the number of processors and
5735the grid point numbers used. Information about the respective settings
5736are 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>
5737
5738
5739
5740
5741
5742
5743
5744      <br>
5745
5746
5747
5748
5749
5750
5751
5752When 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>)
5753only <b>grid_matching</b> = <span style="font-style: italic;">'strict'</span>
5754is allowed.<br>
5755
5756
5757
5758
5759
5760
5761 <br>
5762
5763
5764
5765
5766
5767
5768 <b>Note:</b><br>
5769
5770
5771
5772
5773
5774
5775
5776In some cases for small processor numbers there may be a very bad load
5777balancing among the
5778processors which may reduce the performance of the code.</td>
5779
5780
5781
5782
5783
5784
5785 </tr>
5786
5787
5788
5789
5790
5791
5792
5793    <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
5794switch on the prognostic equation for specific
5795humidity q.<br>
5796
5797
5798
5799
5800
5801
5802 </p>
5803
5804
5805
5806
5807
5808
5809 
5810     
5811     
5812     
5813     
5814     
5815     
5816      <p>The initial vertical
5817profile 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>
5818and <a href="chapter_4.1.html#q_vertical_gradient_level">q_vertical_gradient_level</a>.&nbsp;
5819Boundary conditions can be set via <a href="chapter_4.1.html#q_surface_initial_change">q_surface_initial_change</a>
5820and <a href="chapter_4.1.html#surface_waterflux">surface_waterflux</a>.<br>
5821
5822
5823
5824
5825
5826
5827
5828      </p>
5829
5830
5831
5832
5833
5834
5835
5836If the condensation scheme is switched on (<a href="chapter_4.1.html#cloud_physics">cloud_physics</a>
5837= .TRUE.), q becomes the total liquid water content (sum of specific
5838humidity 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>),
5839this parameter defines the vertical thickness of the turbulent layer up
5840to which the turbulence extracted at the recycling plane (see <a href="chapter_4.1.html#recycling_width">recycling_width</a>)
5841shall be imposed to the inflow. Above this level the turbulence signal
5842is linearly damped to zero. The transition range within which the
5843signal 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>
5844
5845
5846
5847
5848
5849
5850 <td style="vertical-align: top;"><a name="inflow_disturbance_begin"></a><b>inflow_disturbance_<br>
5851
5852
5853
5854
5855
5856
5857
5858begin</b></td>
5859
5860
5861
5862
5863
5864
5865 <td style="vertical-align: top;">I</td>
5866
5867
5868
5869
5870
5871
5872
5873      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(10,</span><br style="font-style: italic;">
5874
5875
5876
5877
5878
5879
5880 <span style="font-style: italic;">nx/2 or ny/2)</span></td>
5881
5882
5883
5884
5885
5886
5887
5888      <td style="vertical-align: top;">Lower
5889limit of the horizontal range for which random perturbations are to be
5890imposed on the horizontal velocity field (gridpoints).<br>
5891
5892
5893
5894
5895
5896
5897 <br>
5898
5899
5900
5901
5902
5903
5904
5905If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5906or <a href="#bc_ns">bc_ns</a>),
5907this parameter gives the gridpoint number (counted horizontally from
5908the inflow)&nbsp; from which on perturbations are imposed on the
5909horizontal velocity field. Perturbations must be switched on with
5910parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5911
5912
5913
5914
5915
5916
5917
5918    </tr>
5919
5920
5921
5922
5923
5924
5925 <tr>
5926
5927
5928
5929
5930
5931
5932 <td style="vertical-align: top;"><a name="inflow_disturbance_end"></a><b>inflow_disturbance_<br>
5933
5934
5935
5936
5937
5938
5939
5940end</b></td>
5941
5942
5943
5944
5945
5946
5947 <td style="vertical-align: top;">I</td>
5948
5949
5950
5951
5952
5953
5954
5955      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(100,</span><br style="font-style: italic;">
5956
5957
5958
5959
5960
5961
5962 <span style="font-style: italic;">3/4*nx or</span><br style="font-style: italic;">
5963
5964
5965
5966
5967
5968
5969 <span style="font-style: italic;">3/4*ny)</span></td>
5970
5971
5972
5973
5974
5975
5976 <td style="vertical-align: top;">Upper
5977limit of the horizontal range for which random perturbations are
5978to be imposed on the horizontal velocity field (gridpoints).<br>
5979
5980
5981
5982
5983
5984
5985 <br>
5986
5987
5988
5989
5990
5991
5992
5993If non-cyclic lateral boundary conditions are used (see <a href="#bc_lr">bc_lr</a>
5994or <a href="#bc_ns">bc_ns</a>),
5995this parameter gives the gridpoint number (counted horizontally from
5996the inflow)&nbsp; unto which perturbations are imposed on the
5997horizontal
5998velocity field. Perturbations must be switched on with parameter <a href="chapter_4.2.html#create_disturbances">create_disturbances</a>.</td>
5999
6000
6001
6002
6003
6004
6005
6006    </tr>
6007
6008
6009
6010
6011
6012
6013 <tr>
6014
6015
6016
6017
6018
6019
6020 <td style="vertical-align: top;">
6021     
6022     
6023     
6024     
6025     
6026     
6027      <p><a name="initializing_actions"></a><b>initializing_actions</b></p>
6028
6029
6030
6031
6032
6033
6034
6035      </td>
6036
6037
6038
6039
6040
6041
6042 <td style="vertical-align: top;">C * 100</td>
6043
6044
6045
6046
6047
6048
6049
6050      <td style="vertical-align: top;"><br>
6051
6052
6053
6054
6055
6056
6057 </td>
6058
6059
6060
6061
6062
6063
6064 <td style="vertical-align: top;"> 
6065     
6066     
6067     
6068     
6069     
6070     
6071      <p style="font-style: normal;">Initialization actions
6072to be carried out.&nbsp; </p>
6073
6074
6075
6076
6077
6078
6079 
6080     
6081     
6082     
6083     
6084     
6085     
6086      <p style="font-style: normal;">This parameter does not have a
6087default value and therefore must be assigned with each model run. For
6088restart runs <b>initializing_actions</b> = <span style="font-style: italic;">'read_restart_data'</span>
6089must be set. For the initial run of a job chain the following values
6090are allowed:&nbsp; </p>
6091
6092
6093
6094
6095
6096
6097 
6098     
6099     
6100     
6101     
6102     
6103     
6104      <p style="font-style: normal;"><span style="font-style: italic;">'set_constant_profiles'</span>
6105      </p>
6106
6107
6108
6109
6110
6111
6112 
6113     
6114     
6115     
6116     
6117     
6118     
6119      <ul>
6120
6121
6122
6123
6124
6125
6126 
6127       
6128       
6129       
6130       
6131       
6132       
6133        <p>A horizontal wind profile consisting
6134of linear sections (see <a href="#ug_surface">ug_surface</a>,
6135        <a href="#ug_vertical_gradient">ug_vertical_gradient</a>,
6136        <a href="#ug_vertical_gradient_level">ug_vertical_gradient_level</a>
6137and <a href="#vg_surface">vg_surface</a>, <a href="#vg_vertical_gradient">vg_vertical_gradient</a>,
6138        <a href="#vg_vertical_gradient_level">vg_vertical_gradient_level</a>,
6139respectively) as well as a vertical temperature (humidity) profile
6140consisting of
6141linear sections (see <a href="#pt_surface">pt_surface</a>,
6142        <a href="#pt_vertical_gradient">pt_vertical_gradient</a>,
6143        <a href="#q_surface">q_surface</a>
6144and <a href="#q_vertical_gradient">q_vertical_gradient</a>)
6145are assumed as initial profiles. The subgrid-scale TKE is set to 0 but K<sub>m</sub>
6146and K<sub>h</sub> are set to very small values because
6147otherwise no TKE
6148would be generated.</p>
6149
6150
6151
6152
6153
6154
6155 
6156     
6157     
6158     
6159     
6160     
6161     
6162      </ul>
6163
6164
6165
6166
6167
6168
6169 
6170     
6171     
6172     
6173     
6174     
6175     
6176      <p style="font-style: italic;">'set_1d-model_profiles' </p>
6177
6178
6179
6180
6181
6182
6183
6184     
6185     
6186     
6187     
6188     
6189     
6190      <ul>
6191
6192
6193
6194
6195
6196
6197 
6198       
6199       
6200       
6201       
6202       
6203       
6204        <p>The arrays of the 3d-model are initialized with
6205the
6206(stationary) solution of the 1d-model. These are the variables e, kh,
6207km, u, v and with Prandtl layer switched on rif, us, usws, vsws. The
6208temperature (humidity) profile consisting of linear sections is set as
6209for 'set_constant_profiles' and assumed as constant in time within the
62101d-model. For steering of the 1d-model a set of parameters with suffix
6211"_1d" (e.g. <a href="#end_time_1d">end_time_1d</a>,
6212        <a href="#damp_level_1d">damp_level_1d</a>)
6213is available.</p>
6214
6215
6216
6217
6218
6219
6220 
6221     
6222     
6223     
6224     
6225     
6226     
6227      </ul>
6228
6229
6230
6231
6232
6233
6234 
6235     
6236     
6237     
6238     
6239     
6240     
6241      <p><span style="font-style: italic;">'by_user'</span></p>
6242
6243
6244
6245
6246
6247
6248     
6249     
6250     
6251     
6252     
6253     
6254      <p style="margin-left: 40px;">The initialization of the arrays
6255of the 3d-model is under complete control of the user and has to be
6256done in routine <a href="chapter_3.5.1.html#user_init_3d_model">user_init_3d_model</a>
6257of the user-interface.<span style="font-style: italic;"></span></p>
6258
6259
6260
6261
6262
6263
6264     
6265     
6266     
6267     
6268     
6269     
6270      <p><span style="font-style: italic;">'initialize_vortex'</span>
6271      </p>
6272
6273
6274
6275
6276
6277
6278 
6279     
6280     
6281     
6282     
6283     
6284     
6285      <div style="margin-left: 40px;">The initial
6286velocity field of the
62873d-model corresponds to a
6288Rankine-vortex with vertical axis. This setting may be used to test
6289advection 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>)
6290are necessary. In order not to distort the vortex, an initial
6291horizontal wind profile constant
6292with height is necessary (to be set by <b>initializing_actions</b>
6293= <span style="font-style: italic;">'set_constant_profiles'</span>)
6294and some other conditions have to be met (neutral stratification,
6295diffusion must be
6296switched off, see <a href="#km_constant">km_constant</a>).
6297The center of the vortex is located at jc = (nx+1)/2. It
6298extends from k = 0 to k = nz+1. Its radius is 8 * <a href="#dx">dx</a>
6299and the exponentially decaying part ranges to 32 * <a href="#dx">dx</a>
6300(see init_rankine.f90). </div>
6301
6302
6303
6304
6305
6306
6307 
6308     
6309     
6310     
6311     
6312     
6313     
6314      <p><span style="font-style: italic;">'initialize_ptanom'</span>
6315      </p>
6316
6317
6318
6319
6320
6321
6322 
6323     
6324     
6325     
6326     
6327     
6328     
6329      <ul>
6330
6331
6332
6333
6334
6335
6336 
6337       
6338       
6339       
6340       
6341       
6342       
6343        <p>A 2d-Gauss-like shape disturbance
6344(x,y) is added to the
6345initial temperature field with radius 10.0 * <a href="#dx">dx</a>
6346and center at jc = (nx+1)/2. This may be used for tests of scalar
6347advection schemes
6348(see <a href="#scalar_advec">scalar_advec</a>).
6349Such tests require a horizontal wind profile constant with hight and
6350diffusion
6351switched off (see <span style="font-style: italic;">'initialize_vortex'</span>).
6352Additionally, the buoyancy term
6353must be switched of in the equation of motion&nbsp; for w (this
6354requires the user to comment out the call of <span style="font-family: monospace;">buoyancy</span> in the
6355source code of <span style="font-family: monospace;">prognostic_equations.f90</span>).</p></ul>
6356
6357
6358
6359
6360
6361
6362 
6363     
6364     
6365     
6366     
6367     
6368     
6369      <p style="font-style: italic;">'cyclic_fill'</p><p style="font-style: normal; margin-left: 40px;">Here,
63703d-data from a precursor run are read by the initial (main) run. The
6371precursor run is allowed to have a smaller domain along x and y
6372compared with the main run. Also, different numbers of processors can
6373be used for these two runs. Limitations are that the precursor run must
6374use cyclic horizontal boundary conditions and that the number of vertical grid points, <a href="#nz">nz</a>, must be same for the precursor run and the main run. If the total domain of the main run is larger than that of the precursor
6375run, the domain is filled by cyclic repetition&nbsp;of the (cyclic)
6376precursor data. This initialization method is recommended if a
6377turbulent 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
6378combined, e.g. <b>initializing_actions</b> = <span style="font-style: italic;">'set_constant_profiles
6379initialize_vortex'</span>, but the values of <span style="font-style: italic;">'set_constant_profiles'</span>,
6380      <span style="font-style: italic;">'set_1d-model_profiles'</span>
6381, and <span style="font-style: italic;">'by_user'</span>
6382must not be given at the same time.</p>
6383
6384
6385
6386
6387
6388
6389 
6390     
6391     
6392     
6393     
6394     
6395     
6396     
6397
6398
6399
6400
6401
6402
6403 </td>
6404
6405
6406
6407
6408
6409
6410 </tr>
6411
6412
6413
6414
6415
6416
6417
6418    <tr>
6419
6420
6421
6422
6423
6424
6425 <td style="vertical-align: top;"> 
6426     
6427     
6428     
6429     
6430     
6431     
6432      <p><a name="km_constant"></a><b>km_constant</b></p>
6433
6434
6435
6436
6437
6438
6439
6440      </td>
6441
6442
6443
6444
6445
6446
6447 <td style="vertical-align: top;">R</td>
6448
6449
6450
6451
6452
6453
6454
6455      <td style="vertical-align: top;"><i>variable<br>
6456
6457
6458
6459
6460
6461
6462
6463(computed from TKE)</i></td>
6464
6465
6466
6467
6468
6469
6470 <td style="vertical-align: top;"> 
6471     
6472     
6473     
6474     
6475     
6476     
6477      <p>Constant eddy
6478diffusivities are used (laminar
6479simulations).&nbsp; </p>
6480
6481
6482
6483
6484
6485
6486 
6487     
6488     
6489     
6490     
6491     
6492     
6493      <p>If this parameter is
6494specified, both in the 1d and in the
64953d-model constant values for the eddy diffusivities are used in
6496space and time with K<sub>m</sub> = <b>km_constant</b>
6497and K<sub>h</sub> = K<sub>m</sub> / <a href="chapter_4.2.html#prandtl_number">prandtl_number</a>.
6498The prognostic equation for the subgrid-scale TKE is switched off.
6499Constant eddy diffusivities are only allowed with the Prandtl layer (<a href="#prandtl_layer">prandtl_layer</a>)
6500switched off.</p>
6501
6502
6503
6504
6505
6506
6507 </td>
6508
6509
6510
6511
6512
6513
6514 </tr>
6515
6516
6517
6518
6519
6520
6521 <tr>
6522
6523
6524
6525
6526
6527
6528 <td style="vertical-align: top;"> 
6529     
6530     
6531     
6532     
6533     
6534     
6535      <p><a name="km_damp_max"></a><b>km_damp_max</b></p>
6536
6537
6538
6539
6540
6541
6542
6543      </td>
6544
6545
6546
6547
6548
6549
6550 <td style="vertical-align: top;">R</td>
6551
6552
6553
6554
6555
6556
6557
6558      <td style="vertical-align: top;"><span style="font-style: italic;">0.5*(dx
6559or dy)</span></td>
6560
6561
6562
6563
6564
6565
6566 <td style="vertical-align: top;">Maximum
6567diffusivity used for filtering the velocity field in the vicinity of
6568the outflow (in m<sup>2</sup>/s).<br>
6569
6570
6571
6572
6573
6574
6575 <br>
6576
6577
6578
6579
6580
6581
6582
6583When using non-cyclic lateral boundaries (see <a href="#bc_lr">bc_lr</a>
6584or <a href="#bc_ns">bc_ns</a>),
6585a smoothing has to be applied to the
6586velocity field in the vicinity of the outflow in order to suppress any
6587reflections of outgoing disturbances. Smoothing is done by increasing
6588the eddy diffusivity along the horizontal direction which is
6589perpendicular to the outflow boundary. Only velocity components
6590parallel to the outflow boundary are filtered (e.g. v and w, if the
6591outflow is along x). Damping is applied from the bottom to the top of
6592the domain.<br>
6593
6594
6595
6596
6597
6598
6599 <br>
6600
6601
6602
6603
6604
6605
6606
6607The horizontal range of the smoothing is controlled by <a href="#outflow_damping_width">outflow_damping_width</a>
6608which defines the number of gridpoints (counted from the outflow
6609boundary) from where on the smoothing is applied. Starting from that
6610point, the eddy diffusivity is linearly increased (from zero to its
6611maximum value given by <span style="font-weight: bold;">km_damp_max</span>)
6612until half of the damping range width, from where it remains constant
6613up to the outflow boundary. If at a certain grid point the eddy
6614diffusivity calculated from the flow field is larger than as described
6615above, it is used instead.<br>
6616
6617
6618
6619
6620
6621
6622 <br>
6623
6624
6625
6626
6627
6628
6629
6630The default value of <span style="font-weight: bold;">km_damp_max</span>
6631has been empirically proven to be sufficient.</td>
6632
6633
6634
6635
6636
6637
6638 </tr>
6639
6640
6641
6642
6643
6644
6645 <tr>
6646
6647      <td style="vertical-align: top;"><a name="lad_surface"></a><span style="font-weight: bold;">lad_surface</span></td>
6648
6649      <td style="vertical-align: top;">R</td>
6650
6651      <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span></td>
6652
6653      <td style="vertical-align: top;">Surface value of the leaf area density (in m<sup>2</sup>/m<sup>3</sup>).<br>
6654
6655      <br>
6656
6657This
6658parameter 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,
6659the leaf area density profile is constructed with <a href="#lad_vertical_gradient">lad_vertical_gradient</a>
6660and <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level
6661      </a>.</td>
6662
6663    </tr>
6664
6665    <tr>
6666
6667      <td style="vertical-align: top;"><a name="lad_vertical_gradient"></a><span style="font-weight: bold;">lad_vertical_gradient</span></td>
6668
6669      <td style="vertical-align: top;">R (10)</td>
6670
6671      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6672
6673      <td style="vertical-align: top;">Gradient(s) of the leaf area density (in&nbsp;m<sup>2</sup>/m<sup>4</sup>).<br>
6674
6675      <br>
6676
6677     
6678      <p>This leaf area density gradient
6679holds starting from the height&nbsp;
6680level defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6681(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>)
6682up 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
6683if <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>(1)
6684= <i>0.0</i>) can be assigned. The leaf area density at the surface is
6685assigned via <a href="#lad_surface">lad_surface</a>.&nbsp;
6686      </p>
6687
6688      </td>
6689
6690    </tr>
6691
6692    <tr>
6693
6694      <td style="vertical-align: top;"><a name="lad_vertical_gradient_level"></a><span style="font-weight: bold;">lad_vertical_gradient_level</span></td>
6695
6696      <td style="vertical-align: top;">R (10)</td>
6697
6698      <td style="vertical-align: top;"><span style="font-style: italic;">10 * 0.0</span></td>
6699
6700      <td style="vertical-align: top;">Height level from which on the&nbsp;gradient
6701of the leaf area density defined by <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>
6702is effective (in m).<br>
6703
6704      <br>
6705
6706The height levels have to be assigned in ascending order. The
6707default 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>
6708
6709    </tr>
6710
6711    <tr>
6712
6713      <td style="vertical-align: top;"><a name="leaf_surface_concentration"></a><b>leaf_surface_concentration</b></td>
6714
6715      <td style="vertical-align: top;">R</td>
6716
6717      <td style="vertical-align: top;"><i>0.0</i></td>
6718
6719      <td style="vertical-align: top;">Concentration of a passive scalar at the surface of a leaf (in K m/s).<br>
6720
6721
6722      <br>
6723
6724
6725This 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>.
6726The value of the concentration of a passive scalar at the surface of a
6727leaf is required for the parametrisation of the sources and sinks of
6728scalar concentration due to the canopy.</td>
6729
6730    </tr>
6731
6732    <tr>
6733
6734
6735
6736
6737
6738
6739
6740      <td style="vertical-align: top;"> 
6741     
6742     
6743     
6744     
6745     
6746     
6747      <p><a name="long_filter_factor"></a><b>long_filter_factor</b></p>
6748
6749
6750
6751
6752
6753
6754
6755      </td>
6756
6757
6758
6759
6760
6761
6762 <td style="vertical-align: top;">R</td>
6763
6764
6765
6766
6767
6768
6769
6770      <td style="vertical-align: top;"><i>0.0</i></td>
6771
6772
6773
6774
6775
6776
6777
6778      <td style="vertical-align: top;"> 
6779     
6780     
6781     
6782     
6783     
6784     
6785      <p>Filter factor
6786for the so-called Long-filter.<br>
6787
6788
6789
6790
6791
6792
6793 </p>
6794
6795
6796
6797
6798
6799
6800 
6801     
6802     
6803     
6804     
6805     
6806     
6807      <p><br>
6808
6809
6810
6811
6812
6813
6814
6815This filter very efficiently
6816eliminates 2-delta-waves sometimes cauesed by the upstream-spline
6817scheme (see Mahrer and
6818Pielke, 1978: Mon. Wea. Rev., 106, 818-830). It works in all three
6819directions in space. A value of <b>long_filter_factor</b>
6820= <i>0.01</i>
6821sufficiently removes the small-scale waves without affecting the
6822longer waves.<br>
6823
6824
6825
6826
6827
6828
6829 </p>
6830
6831
6832
6833
6834
6835
6836 
6837     
6838     
6839     
6840     
6841     
6842     
6843      <p>By default, the filter is
6844switched off (= <i>0.0</i>).
6845It is exclusively applied to the tendencies calculated by the
6846upstream-spline scheme (see <a href="#momentum_advec">momentum_advec</a>
6847and <a href="#scalar_advec">scalar_advec</a>),
6848not to the prognostic variables themselves. At the bottom and top
6849boundary of the model domain the filter effect for vertical
68502-delta-waves is reduced. There, the amplitude of these waves is only
6851reduced by approx. 50%, otherwise by nearly 100%.&nbsp; <br>
6852
6853
6854
6855
6856
6857
6858
6859Filter factors with values &gt; <i>0.01</i> also
6860reduce the amplitudes
6861of waves with wavelengths longer than 2-delta (see the paper by Mahrer
6862and
6863Pielke, quoted above). </p>
6864
6865
6866
6867
6868
6869
6870 </td>
6871
6872
6873
6874
6875
6876
6877 </tr>
6878
6879
6880
6881
6882
6883
6884 <tr>
6885
6886
6887
6888
6889
6890
6891      <td style="vertical-align: top;"><a name="loop_optimization"></a><span style="font-weight: bold;">loop_optimization</span></td>
6892
6893
6894
6895
6896
6897
6898      <td style="vertical-align: top;">C*16</td>
6899
6900
6901
6902
6903
6904
6905      <td style="vertical-align: top;"><span style="font-style: italic;">see right</span></td>
6906
6907
6908
6909
6910
6911
6912      <td>Method used to optimize loops for solving the prognostic equations .<br>
6913
6914
6915
6916
6917
6918
6919      <br>
6920
6921
6922
6923
6924
6925
6926By
6927default, the optimization method depends on the host on which PALM is
6928running. On machines with vector-type CPUs, single 3d-loops are used to
6929calculate each tendency term of each prognostic equation, while on all
6930other machines, all prognostic equations are solved within one big loop
6931over 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>
6932
6933
6934
6935
6936
6937
6938      <br>
6939
6940
6941
6942
6943
6944
6945The 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>
6946
6947
6948
6949
6950
6951
6952    </tr>
6953
6954
6955
6956
6957
6958
6959    <tr>
6960
6961
6962
6963
6964
6965
6966
6967      <td style="vertical-align: top;"><a name="mixing_length_1d"></a><span style="font-weight: bold;">mixing_length_1d</span><br>
6968
6969
6970
6971
6972
6973
6974
6975      </td>
6976
6977
6978
6979
6980
6981
6982 <td style="vertical-align: top;">C*20<br>
6983
6984
6985
6986
6987
6988
6989
6990      </td>
6991
6992
6993
6994
6995
6996
6997 <td style="vertical-align: top;"><span style="font-style: italic;">'as_in_3d_</span><br style="font-style: italic;">
6998
6999
7000
7001
7002
7003
7004 <span style="font-style: italic;">model'</span><br>
7005
7006
7007
7008
7009
7010
7011 </td>
7012
7013
7014
7015
7016
7017
7018
7019      <td style="vertical-align: top;">Mixing length used in the
70201d-model.<br>
7021
7022
7023
7024
7025
7026
7027 <br>
7028
7029
7030
7031
7032
7033
7034
7035By default the mixing length is calculated as in the 3d-model (i.e. it
7036depends on the grid spacing).<br>
7037
7038
7039
7040
7041
7042
7043 <br>
7044
7045
7046
7047
7048
7049
7050
7051By setting <span style="font-weight: bold;">mixing_length_1d</span>
7052= <span style="font-style: italic;">'blackadar'</span>,
7053the so-called Blackadar mixing length is used (l = kappa * z / ( 1 +
7054kappa * z / lambda ) with the limiting value lambda = 2.7E-4 * u_g / f).<br>
7055
7056
7057
7058
7059
7060
7061
7062      </td>
7063
7064
7065
7066
7067
7068
7069 </tr>
7070
7071
7072
7073
7074
7075
7076 
7077
7078
7079
7080
7081
7082
7083
7084    <tr>
7085
7086
7087
7088
7089
7090
7091 <td style="vertical-align: top;"> 
7092     
7093     
7094     
7095     
7096     
7097     
7098      <p><a name="momentum_advec"></a><b>momentum_advec</b></p>
7099
7100
7101
7102
7103
7104
7105
7106      </td>
7107
7108
7109
7110
7111
7112
7113 <td style="vertical-align: top;">C * 10</td>
7114
7115
7116
7117
7118
7119
7120
7121      <td style="vertical-align: top;"><i>'pw-scheme'</i></td>
7122
7123
7124
7125
7126
7127
7128
7129      <td style="vertical-align: top;"> 
7130     
7131     
7132     
7133     
7134     
7135     
7136      <p>Advection
7137scheme to be used for the momentum equations.<br>
7138
7139
7140
7141
7142
7143
7144 <br>
7145
7146
7147
7148
7149
7150
7151
7152The user can choose between the following schemes:<br>
7153
7154
7155
7156
7157
7158
7159
7160&nbsp;<br>
7161
7162
7163
7164
7165
7166
7167 <br>
7168
7169
7170
7171
7172
7173
7174 <span style="font-style: italic;">'pw-scheme'</span><br>
7175
7176
7177
7178
7179
7180
7181
7182      </p>
7183
7184
7185
7186
7187
7188
7189 
7190     
7191     
7192     
7193     
7194     
7195     
7196      <div style="margin-left: 40px;">The scheme of
7197Piascek and
7198Williams (1970, J. Comp. Phys., 6,
7199392-405) with central differences in the form C3 is used.<br>
7200
7201
7202
7203
7204
7205
7206
7207If intermediate Euler-timesteps are carried out in case of <a href="#timestep_scheme">timestep_scheme</a>
7208= <span style="font-style: italic;">'leapfrog+euler'</span>
7209the
7210advection scheme is - for the Euler-timestep - automatically switched
7211to an upstream-scheme.<br>
7212
7213
7214
7215
7216
7217
7218 </div>
7219
7220
7221
7222
7223
7224
7225 
7226     
7227     
7228     
7229     
7230     
7231     
7232      <p> </p>
7233
7234
7235
7236
7237
7238
7239 
7240     
7241     
7242     
7243     
7244     
7245     
7246      <p><span style="font-style: italic;">'ups-scheme'</span><br>
7247
7248
7249
7250
7251
7252
7253
7254      </p>
7255
7256
7257
7258
7259
7260
7261 
7262     
7263     
7264     
7265     
7266     
7267     
7268      <div style="margin-left: 40px;">The
7269upstream-spline scheme is
7270used
7271(see Mahrer and Pielke,
72721978: Mon. Wea. Rev., 106, 818-830). In opposite to the
7273Piascek-Williams scheme, this is characterized by much better numerical
7274features (less numerical diffusion, better preservation of flow
7275structures, e.g. vortices), but computationally it is much more
7276expensive. In
7277addition, the use of the Euler-timestep scheme is mandatory (<a href="#timestep_scheme">timestep_scheme</a>
7278= <span style="font-style: italic;">'</span><i>euler'</i>),
7279i.e. the
7280timestep accuracy is only of first order.
7281For this reason the advection of scalar variables (see <a href="#scalar_advec">scalar_advec</a>)
7282should then also be carried out with the upstream-spline scheme,
7283because otherwise the scalar variables would
7284be subject to large numerical diffusion due to the upstream
7285scheme.&nbsp; </div>
7286
7287
7288
7289
7290
7291
7292 
7293     
7294     
7295     
7296     
7297     
7298     
7299      <p style="margin-left: 40px;">Since
7300the cubic splines used tend
7301to overshoot under
7302certain circumstances, this effect must be adjusted by suitable
7303filtering and smoothing (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>,
7304      <a href="#long_filter_factor">long_filter_factor</a>,
7305      <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>).
7306This is always neccessary for runs with stable stratification,
7307even if this stratification appears only in parts of the model domain.<br>
7308
7309
7310
7311
7312
7313
7314
7315      </p>
7316
7317
7318
7319
7320
7321
7322 
7323     
7324     
7325     
7326     
7327     
7328     
7329      <div style="margin-left: 40px;">With stable
7330stratification the
7331upstream-spline scheme also
7332produces gravity waves with large amplitude, which must be
7333suitably damped (see <a href="chapter_4.2.html#rayleigh_damping_factor">rayleigh_damping_factor</a>).<br>
7334
7335
7336
7337
7338
7339
7340
7341      <br>
7342
7343
7344
7345
7346
7347
7348 <span style="font-weight: bold;">Important: </span>The&nbsp;
7349upstream-spline scheme is not implemented for humidity and passive
7350scalars (see&nbsp;<a href="#humidity">humidity</a>
7351and <a href="#passive_scalar">passive_scalar</a>)
7352and requires the use of a 2d-domain-decomposition. The last conditions
7353severely restricts code optimization on several machines leading to
7354very long execution times! The scheme is also not allowed for
7355non-cyclic lateral boundary conditions (see <a href="#bc_lr">bc_lr</a>
7356and <a href="#bc_ns">bc_ns</a>).</div>
7357
7358
7359
7360
7361
7362
7363 </td>
7364
7365
7366
7367
7368
7369
7370
7371    </tr>
7372
7373
7374
7375
7376
7377
7378 <tr>
7379
7380
7381
7382
7383
7384
7385 <td style="vertical-align: top;"><a name="netcdf_precision"></a><span style="font-weight: bold;">netcdf_precision</span><br>
7386
7387
7388
7389
7390
7391
7392
7393      </td>
7394
7395
7396
7397
7398
7399
7400 <td style="vertical-align: top;">C*20<br>
7401
7402
7403
7404
7405
7406
7407
7408(10)<br>
7409
7410
7411
7412
7413
7414
7415 </td>
7416
7417
7418
7419
7420
7421
7422 <td style="vertical-align: top;"><span style="font-style: italic;">single preci-</span><br style="font-style: italic;">
7423
7424
7425
7426
7427
7428
7429 <span style="font-style: italic;">sion for all</span><br style="font-style: italic;">
7430
7431
7432
7433
7434
7435
7436 <span style="font-style: italic;">output quan-</span><br style="font-style: italic;">
7437
7438
7439
7440
7441
7442
7443 <span style="font-style: italic;">tities</span><br>
7444
7445
7446
7447
7448
7449
7450 </td>
7451
7452
7453
7454
7455
7456
7457
7458      <td style="vertical-align: top;">Defines the accuracy of
7459the NetCDF output.<br>
7460
7461
7462
7463
7464
7465
7466 <br>
7467
7468
7469
7470
7471
7472
7473
7474By default, all NetCDF output data (see <a href="chapter_4.2.html#data_output_format">data_output_format</a>)
7475have single precision&nbsp; (4 byte) accuracy. Double precision (8
7476byte) can be choosen alternatively.<br>
7477
7478
7479
7480
7481
7482
7483
7484Accuracy for the different output data (cross sections, 3d-volume data,
7485spectra, etc.) can be set independently.<br>
7486
7487
7488
7489
7490
7491
7492 <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL4'</span>
7493(single precision) or <span style="font-style: italic;">'&lt;out&gt;_NF90_REAL8'</span>
7494(double precision) are the two principally allowed values for <span style="font-weight: bold;">netcdf_precision</span>,
7495where the string <span style="font-style: italic;">'&lt;out&gt;'
7496      </span>can be chosen out of the following list:<br>
7497
7498
7499
7500
7501
7502
7503 <br>
7504
7505
7506
7507
7508
7509
7510
7511     
7512     
7513     
7514     
7515     
7516     
7517      <table style="text-align: left; width: 284px; height: 234px;" border="1" cellpadding="2" cellspacing="2">
7518
7519
7520
7521
7522
7523
7524 <tbody>
7525
7526
7527
7528
7529
7530
7531
7532          <tr>
7533
7534
7535
7536
7537
7538
7539 <td style="vertical-align: top;"><span style="font-style: italic;">'xy'</span><br>
7540
7541
7542
7543
7544
7545
7546 </td>
7547
7548
7549
7550
7551
7552
7553
7554            <td style="vertical-align: top;">horizontal cross section<br>
7555
7556
7557
7558
7559
7560
7561
7562            </td>
7563
7564
7565
7566
7567
7568
7569 </tr>
7570
7571
7572
7573
7574
7575
7576 <tr>
7577
7578
7579
7580
7581
7582
7583 <td style="vertical-align: top;"><span style="font-style: italic;">'xz'</span><br>
7584
7585
7586
7587
7588
7589
7590 </td>
7591
7592
7593
7594
7595
7596
7597
7598            <td style="vertical-align: top;">vertical (xz) cross
7599section<br>
7600
7601
7602
7603
7604
7605
7606 </td>
7607
7608
7609
7610
7611
7612
7613 </tr>
7614
7615
7616
7617
7618
7619
7620 <tr>
7621
7622
7623
7624
7625
7626
7627 <td style="vertical-align: top;"><span style="font-style: italic;">'yz'</span><br>
7628
7629
7630
7631
7632
7633
7634 </td>
7635
7636
7637
7638
7639
7640
7641
7642            <td style="vertical-align: top;">vertical (yz) cross
7643section<br>
7644
7645
7646
7647
7648
7649
7650 </td>
7651
7652
7653
7654
7655
7656
7657 </tr>
7658
7659
7660
7661
7662
7663
7664 <tr>
7665
7666
7667
7668
7669
7670
7671 <td style="vertical-align: top;"><span style="font-style: italic;">'2d'</span><br>
7672
7673
7674
7675
7676
7677
7678 </td>
7679
7680
7681
7682
7683
7684
7685
7686            <td style="vertical-align: top;">all cross sections<br>
7687
7688
7689
7690
7691
7692
7693
7694            </td>
7695
7696
7697
7698
7699
7700
7701 </tr>
7702
7703
7704
7705
7706
7707
7708 <tr>
7709
7710
7711
7712
7713
7714
7715 <td style="vertical-align: top;"><span style="font-style: italic;">'3d'</span><br>
7716
7717
7718
7719
7720
7721
7722 </td>
7723
7724
7725
7726
7727
7728
7729
7730            <td style="vertical-align: top;">volume data<br>
7731
7732
7733
7734
7735
7736
7737 </td>
7738
7739
7740
7741
7742
7743
7744
7745          </tr>
7746
7747
7748
7749
7750
7751
7752 <tr>
7753
7754
7755
7756
7757
7758
7759 <td style="vertical-align: top;"><span style="font-style: italic;">'pr'</span><br>
7760
7761
7762
7763
7764
7765
7766 </td>
7767
7768
7769
7770
7771
7772
7773
7774            <td style="vertical-align: top;">vertical profiles<br>
7775
7776
7777
7778
7779
7780
7781
7782            </td>
7783
7784
7785
7786
7787
7788
7789 </tr>
7790
7791
7792
7793
7794
7795
7796 <tr>
7797
7798
7799
7800
7801
7802
7803 <td style="vertical-align: top;"><span style="font-style: italic;">'ts'</span><br>
7804
7805
7806
7807
7808
7809
7810 </td>
7811
7812
7813
7814
7815
7816
7817
7818            <td style="vertical-align: top;">time series, particle
7819time series<br>
7820
7821
7822
7823
7824
7825
7826 </td>
7827
7828
7829
7830
7831
7832
7833 </tr>
7834
7835
7836
7837
7838
7839
7840 <tr>
7841
7842
7843
7844
7845
7846
7847 <td style="vertical-align: top;"><span style="font-style: italic;">'sp'</span><br>
7848
7849
7850
7851
7852
7853
7854 </td>
7855
7856
7857
7858
7859
7860
7861
7862            <td style="vertical-align: top;">spectra<br>
7863
7864
7865
7866
7867
7868
7869 </td>
7870
7871
7872
7873
7874
7875
7876
7877          </tr>
7878
7879
7880
7881
7882
7883
7884 <tr>
7885
7886
7887
7888
7889
7890
7891 <td style="vertical-align: top;"><span style="font-style: italic;">'prt'</span><br>
7892
7893
7894
7895
7896
7897
7898 </td>
7899
7900
7901
7902
7903
7904
7905
7906            <td style="vertical-align: top;">particles<br>
7907
7908
7909
7910
7911
7912
7913 </td>
7914
7915
7916
7917
7918
7919
7920
7921          </tr>
7922
7923
7924
7925
7926
7927
7928 <tr>
7929
7930
7931
7932
7933
7934
7935 <td style="vertical-align: top;"><span style="font-style: italic;">'all'</span><br>
7936
7937
7938
7939
7940
7941
7942 </td>
7943
7944
7945
7946
7947
7948
7949
7950            <td style="vertical-align: top;">all output quantities<br>
7951
7952
7953
7954
7955
7956
7957
7958            </td>
7959
7960
7961
7962
7963
7964
7965 </tr>
7966
7967
7968
7969
7970
7971
7972 
7973       
7974       
7975       
7976       
7977       
7978       
7979        </tbody> 
7980     
7981     
7982     
7983     
7984     
7985     
7986      </table>
7987
7988
7989
7990
7991
7992
7993 <br>
7994
7995
7996
7997
7998
7999
8000 <span style="font-weight: bold;">Example:</span><br>
8001
8002
8003
8004
8005
8006
8007
8008If all cross section data and the particle data shall be output in
8009double 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>
8010has to be assigned.<br>
8011
8012
8013
8014
8015
8016
8017 </td>
8018
8019
8020
8021
8022
8023
8024 </tr>
8025
8026
8027
8028
8029
8030
8031
8032   
8033
8034
8035
8036
8037
8038
8039 
8040
8041
8042
8043
8044
8045
8046
8047    <tr>
8048
8049
8050
8051
8052
8053
8054 <td style="vertical-align: top;"> 
8055     
8056     
8057     
8058     
8059     
8060     
8061      <p><a name="nsor_ini"></a><b>nsor_ini</b></p>
8062
8063
8064
8065
8066
8067
8068
8069      </td>
8070
8071
8072
8073
8074
8075
8076 <td style="vertical-align: top;">I</td>
8077
8078
8079
8080
8081
8082
8083
8084      <td style="vertical-align: top;"><i>100</i></td>
8085
8086
8087
8088
8089
8090
8091
8092      <td style="vertical-align: top;"> 
8093     
8094     
8095     
8096     
8097     
8098     
8099      <p>Initial number
8100of iterations with the SOR algorithm.&nbsp; </p>
8101
8102
8103
8104
8105
8106
8107 
8108     
8109     
8110     
8111     
8112     
8113     
8114      <p>This
8115parameter is only effective if the SOR algorithm was
8116selected as the pressure solver scheme (<a href="chapter_4.2.html#psolver">psolver</a>
8117= <span style="font-style: italic;">'sor'</span>)
8118and specifies the
8119number of initial iterations of the SOR
8120scheme (at t = 0). The number of subsequent iterations at the following
8121timesteps is determined
8122with the parameter <a href="#nsor">nsor</a>.
8123Usually <b>nsor</b> &lt; <b>nsor_ini</b>,
8124since in each case
8125subsequent calls to <a href="chapter_4.2.html#psolver">psolver</a>
8126use the solution of the previous call as initial value. Suitable
8127test runs should determine whether sufficient convergence of the
8128solution is obtained with the default value and if necessary the value
8129of <b>nsor_ini</b> should be changed.</p>
8130
8131
8132
8133
8134
8135
8136 </td>
8137
8138
8139
8140
8141
8142
8143
8144    </tr>
8145
8146
8147
8148
8149
8150
8151 <tr>
8152
8153
8154
8155
8156
8157
8158 <td style="vertical-align: top;">
8159     
8160     
8161     
8162     
8163     
8164     
8165      <p><a name="nx"></a><b>nx</b></p>
8166
8167
8168
8169
8170
8171
8172
8173      </td>
8174
8175
8176
8177
8178
8179
8180 <td style="vertical-align: top;">I</td>
8181
8182
8183
8184
8185
8186
8187
8188      <td style="vertical-align: top;"><br>
8189
8190
8191
8192
8193
8194
8195 </td>
8196
8197
8198
8199
8200
8201
8202 <td style="vertical-align: top;"> 
8203     
8204     
8205     
8206     
8207     
8208     
8209      <p>Number of grid
8210points in x-direction.&nbsp; </p>
8211
8212
8213
8214
8215
8216
8217 
8218     
8219     
8220     
8221     
8222     
8223     
8224      <p>A value for this
8225parameter must be assigned. Since the lower
8226array bound in PALM
8227starts with i = 0, the actual number of grid points is equal to <b>nx+1</b>.
8228In case of cyclic boundary conditions along x, the domain size is (<b>nx+1</b>)*
8229      <a href="#dx">dx</a>.</p>
8230
8231
8232
8233
8234
8235
8236 
8237     
8238     
8239     
8240     
8241     
8242     
8243      <p>For
8244parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8245= <span style="font-style: italic;">'strict'</span>,
8246      <b>nx+1</b> must
8247be an integral multiple
8248of the processor numbers (see <a href="#npex">npex</a>
8249and <a href="#npey">npey</a>)
8250along x- as well as along y-direction (due to data
8251transposition restrictions).</p>
8252
8253
8254
8255
8256
8257
8258     
8259     
8260     
8261     
8262     
8263     
8264      <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>
8265and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8266
8267
8268
8269
8270
8271
8272 </td>
8273
8274
8275
8276
8277
8278
8279 </tr>
8280
8281
8282
8283
8284
8285
8286 <tr>
8287
8288
8289
8290
8291
8292
8293
8294      <td style="vertical-align: top;"> 
8295     
8296     
8297     
8298     
8299     
8300     
8301      <p><a name="ny"></a><b>ny</b></p>
8302
8303
8304
8305
8306
8307
8308
8309      </td>
8310
8311
8312
8313
8314
8315
8316 <td style="vertical-align: top;">I</td>
8317
8318
8319
8320
8321
8322
8323
8324      <td style="vertical-align: top;"><br>
8325
8326
8327
8328
8329
8330
8331 </td>
8332
8333
8334
8335
8336
8337
8338 <td style="vertical-align: top;"> 
8339     
8340     
8341     
8342     
8343     
8344     
8345      <p>Number of grid
8346points in y-direction.&nbsp; </p>
8347
8348
8349
8350
8351
8352
8353 
8354     
8355     
8356     
8357     
8358     
8359     
8360      <p>A value for this
8361parameter must be assigned. Since the lower
8362array bound in PALM starts with j = 0, the actual number of grid points
8363is equal to <b>ny+1</b>. In case of cyclic boundary
8364conditions along
8365y, the domain size is (<b>ny+1</b>) * <a href="#dy">dy</a>.</p>
8366
8367
8368
8369
8370
8371
8372
8373     
8374     
8375     
8376     
8377     
8378     
8379      <p>For parallel runs, in case of <a href="#grid_matching">grid_matching</a>
8380= <span style="font-style: italic;">'strict'</span>,
8381      <b>ny+1</b> must
8382be an integral multiple
8383of the processor numbers (see <a href="#npex">npex</a>
8384and <a href="#npey">npey</a>)&nbsp;
8385along y- as well as along x-direction (due to data
8386transposition restrictions).</p>
8387
8388
8389
8390
8391
8392
8393     
8394     
8395     
8396     
8397     
8398     
8399      <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>
8400and&nbsp;<a href="chapter_3.4.html#PARIN"><font style="font-size: 10pt;" size="2">PARIN_O</font></a>.</p>
8401
8402
8403
8404
8405
8406
8407 </td>
8408
8409
8410
8411
8412
8413
8414 </tr>
8415
8416
8417
8418
8419
8420
8421 <tr>
8422
8423
8424
8425
8426
8427
8428
8429      <td style="vertical-align: top;"> 
8430     
8431     
8432     
8433     
8434     
8435     
8436      <p><a name="nz"></a><b>nz</b></p>
8437
8438
8439
8440
8441
8442
8443
8444      </td>
8445
8446
8447
8448
8449
8450
8451 <td style="vertical-align: top;">I</td>
8452
8453
8454
8455
8456
8457
8458
8459      <td style="vertical-align: top;"><br>
8460
8461
8462
8463
8464
8465
8466 </td>
8467
8468
8469
8470
8471
8472
8473 <td style="vertical-align: top;"> 
8474     
8475     
8476     
8477     
8478     
8479     
8480      <p>Number of grid
8481points in z-direction.&nbsp; </p>
8482
8483
8484
8485
8486
8487
8488 
8489     
8490     
8491     
8492     
8493     
8494     
8495      <p>A value for this
8496parameter must be assigned. Since the lower
8497array bound in PALM
8498starts with k = 0 and since one additional grid point is added at the
8499top boundary (k = <b>nz+1</b>), the actual number of grid
8500points is <b>nz+2</b>.
8501However, the prognostic equations are only solved up to <b>nz</b>
8502(u,
8503v)
8504or up to <b>nz-1</b> (w, scalar quantities). The top
8505boundary for u
8506and v is at k = <b>nz+1</b> (u, v) while at k = <b>nz</b>
8507for all
8508other quantities.&nbsp; </p>
8509
8510
8511
8512
8513
8514
8515 
8516     
8517     
8518     
8519     
8520     
8521     
8522      <p>For parallel
8523runs,&nbsp; in case of <a href="#grid_matching">grid_matching</a>
8524= <span style="font-style: italic;">'strict'</span>,
8525      <b>nz</b> must
8526be an integral multiple of
8527the number of processors in x-direction (due to data transposition
8528restrictions).</p>
8529
8530
8531
8532
8533
8534
8535 </td>
8536
8537
8538
8539
8540
8541
8542 </tr>
8543
8544
8545
8546
8547
8548
8549 <tr>
8550
8551
8552
8553
8554
8555
8556      <td style="vertical-align: top;"><a name="ocean"></a><span style="font-weight: bold;">ocean</span></td>
8557
8558
8559
8560
8561
8562
8563      <td style="vertical-align: top;">L</td>
8564
8565
8566
8567
8568
8569
8570      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
8571
8572
8573
8574
8575
8576
8577      <td style="vertical-align: top;">Parameter to switch on&nbsp;ocean runs.<br>
8578
8579
8580
8581
8582
8583
8584      <br>
8585
8586
8587
8588
8589
8590
8591By 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>
8592
8593
8594
8595
8596
8597
8598      <br>
8599
8600
8601
8602
8603
8604
8605     
8606     
8607     
8608     
8609     
8610     
8611      <ul>
8612
8613
8614
8615
8616
8617
8618        <li>An additional prognostic equation for salinity is solved.</li>
8619
8620
8621
8622
8623
8624
8625        <li>Potential temperature in buoyancy and stability-related terms is replaced by potential density.</li>
8626
8627
8628
8629
8630
8631
8632        <li>Potential
8633density is calculated from the equation of state for seawater after
8634each timestep, using the algorithm proposed by Jackett et al. (2006, J.
8635Atmos. Oceanic Technol., <span style="font-weight: bold;">23</span>, 1709-1728).<br>
8636
8637
8638
8639
8640
8641
8642So far, only the initial hydrostatic pressure is entered into this equation.</li>
8643
8644
8645
8646
8647
8648
8649        <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>
8650
8651
8652
8653
8654
8655
8656        <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>
8657
8658
8659
8660
8661
8662
8663        <li>Zero salinity flux is used as default boundary condition at the bottom of the sea.</li>
8664
8665
8666
8667
8668
8669
8670        <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>
8671
8672
8673
8674
8675
8676
8677     
8678     
8679     
8680     
8681     
8682     
8683      </ul>
8684
8685
8686
8687
8688
8689
8690      <br>
8691
8692
8693
8694
8695
8696
8697Relevant 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>
8698
8699
8700
8701
8702
8703
8704      <br>
8705
8706
8707
8708
8709
8710
8711Section <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>
8712
8713
8714
8715
8716
8717
8718      <br>
8719
8720
8721
8722
8723
8724
8725      <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>
8726
8727
8728
8729      </td>
8730
8731
8732
8733
8734
8735
8736    </tr>
8737
8738
8739
8740
8741
8742
8743    <tr>
8744
8745
8746
8747
8748
8749
8750 <td style="vertical-align: top;"> 
8751     
8752     
8753     
8754     
8755     
8756     
8757      <p><a name="omega"></a><b>omega</b></p>
8758
8759
8760
8761
8762
8763
8764
8765      </td>
8766
8767
8768
8769
8770
8771
8772 <td style="vertical-align: top;">R</td>
8773
8774
8775
8776
8777
8778
8779
8780      <td style="vertical-align: top;"><i>7.29212E-5</i></td>
8781
8782
8783
8784
8785
8786
8787
8788      <td style="vertical-align: top;"> 
8789     
8790     
8791     
8792     
8793     
8794     
8795      <p>Angular
8796velocity of the rotating system (in rad s<sup>-1</sup>).&nbsp;
8797      </p>
8798
8799
8800
8801
8802
8803
8804 
8805     
8806     
8807     
8808     
8809     
8810     
8811      <p>The angular velocity of the earth is set by
8812default. The
8813values
8814of the Coriolis parameters are calculated as:&nbsp; </p>
8815
8816
8817
8818
8819
8820
8821 
8822     
8823     
8824     
8825     
8826     
8827     
8828      <ul>
8829
8830
8831
8832
8833
8834
8835
8836       
8837       
8838       
8839       
8840       
8841       
8842        <p>f = 2.0 * <b>omega</b> * sin(<a href="#phi">phi</a>)&nbsp;
8843        <br>
8844
8845
8846
8847
8848
8849
8850f* = 2.0 * <b>omega</b> * cos(<a href="#phi">phi</a>)</p>
8851
8852
8853
8854
8855
8856
8857
8858     
8859     
8860     
8861     
8862     
8863     
8864      </ul>
8865
8866
8867
8868
8869
8870
8871 </td>
8872
8873
8874
8875
8876
8877
8878 </tr>
8879
8880
8881
8882
8883
8884
8885 <tr>
8886
8887
8888
8889
8890
8891
8892 <td style="vertical-align: top;"> 
8893     
8894     
8895     
8896     
8897     
8898     
8899      <p><a name="outflow_damping_width"></a><b>outflow_damping_width</b></p>
8900
8901
8902
8903
8904
8905
8906
8907      </td>
8908
8909
8910
8911
8912
8913
8914 <td style="vertical-align: top;">I</td>
8915
8916
8917
8918
8919
8920
8921
8922      <td style="vertical-align: top;"><span style="font-style: italic;">MIN(20,
8923nx/2</span> or <span style="font-style: italic;">ny/2)</span></td>
8924
8925
8926
8927
8928
8929
8930
8931      <td style="vertical-align: top;">Width of
8932the damping range in the vicinity of the outflow (gridpoints).<br>
8933
8934
8935
8936
8937
8938
8939
8940      <br>
8941
8942
8943
8944
8945
8946
8947
8948When using non-cyclic lateral boundaries (see <a href="chapter_4.1.html#bc_lr">bc_lr</a>
8949or <a href="chapter_4.1.html#bc_ns">bc_ns</a>),
8950a smoothing has to be applied to the
8951velocity field in the vicinity of the outflow in order to suppress any
8952reflections of outgoing disturbances. This parameter controlls the
8953horizontal range to which the smoothing is applied. The range is given
8954in gridpoints counted from the respective outflow boundary. For further
8955details about the smoothing see parameter <a href="chapter_4.1.html#km_damp_max">km_damp_max</a>,
8956which defines the magnitude of the damping.</td>
8957
8958
8959
8960
8961
8962
8963 </tr>
8964
8965
8966
8967
8968
8969
8970
8971    <tr>
8972
8973
8974
8975
8976
8977
8978 <td style="vertical-align: top;"> 
8979     
8980     
8981     
8982     
8983     
8984     
8985      <p><a name="overshoot_limit_e"></a><b>overshoot_limit_e</b></p>
8986
8987
8988
8989
8990
8991
8992
8993      </td>
8994
8995
8996
8997
8998
8999
9000 <td style="vertical-align: top;">R</td>
9001
9002
9003
9004
9005
9006
9007
9008      <td style="vertical-align: top;"><i>0.0</i></td>
9009
9010
9011
9012
9013
9014
9015
9016      <td style="vertical-align: top;"> 
9017     
9018     
9019     
9020     
9021     
9022     
9023      <p>Allowed limit
9024for the overshooting of subgrid-scale TKE in
9025case that the upstream-spline scheme is switched on (in m<sup>2</sup>/s<sup>2</sup>).&nbsp;
9026      </p>
9027
9028
9029
9030
9031
9032
9033 
9034     
9035     
9036     
9037     
9038     
9039     
9040      <p>By deafult, if cut-off of overshoots is switched
9041on for the
9042upstream-spline scheme (see <a href="#cut_spline_overshoot">cut_spline_overshoot</a>),
9043no overshoots are permitted at all. If <b>overshoot_limit_e</b>
9044is given a non-zero value, overshoots with the respective
9045amplitude (both upward and downward) are allowed.&nbsp; </p>
9046
9047
9048
9049
9050
9051
9052
9053     
9054     
9055     
9056     
9057     
9058     
9059      <p>Only positive values are allowed for <b>overshoot_limit_e</b>.</p>
9060
9061
9062
9063
9064
9065
9066
9067      </td>
9068
9069
9070
9071
9072
9073
9074 </tr>
9075
9076
9077
9078
9079
9080
9081 <tr>
9082
9083
9084
9085
9086
9087
9088 <td style="vertical-align: top;"> 
9089     
9090     
9091     
9092     
9093     
9094     
9095      <p><a name="overshoot_limit_pt"></a><b>overshoot_limit_pt</b></p>
9096
9097
9098
9099
9100
9101
9102
9103      </td>
9104
9105
9106
9107
9108
9109
9110 <td style="vertical-align: top;">R</td>
9111
9112
9113
9114
9115
9116
9117
9118      <td style="vertical-align: top;"><i>0.0</i></td>
9119
9120
9121
9122
9123
9124
9125
9126      <td style="vertical-align: top;"> 
9127     
9128     
9129     
9130     
9131     
9132     
9133      <p>Allowed limit
9134for the overshooting of potential temperature in
9135case that the upstream-spline scheme is switched on (in K).&nbsp; </p>
9136
9137
9138
9139
9140
9141
9142
9143     
9144     
9145     
9146     
9147     
9148     
9149      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9150      </p>
9151
9152
9153
9154
9155
9156
9157 
9158     
9159     
9160     
9161     
9162     
9163     
9164      <p>Only positive values are allowed for <b>overshoot_limit_pt</b>.</p>
9165
9166
9167
9168
9169
9170
9171
9172      </td>
9173
9174
9175
9176
9177
9178
9179 </tr>
9180
9181
9182
9183
9184
9185
9186 <tr>
9187
9188
9189
9190
9191
9192
9193 <td style="vertical-align: top;"> 
9194     
9195     
9196     
9197     
9198     
9199     
9200      <p><a name="overshoot_limit_u"></a><b>overshoot_limit_u</b></p>
9201
9202
9203
9204
9205
9206
9207
9208      </td>
9209
9210
9211
9212
9213
9214
9215 <td style="vertical-align: top;">R</td>
9216
9217
9218
9219
9220
9221
9222
9223      <td style="vertical-align: top;"><i>0.0</i></td>
9224
9225
9226
9227
9228
9229
9230
9231      <td style="vertical-align: top;">Allowed limit for the
9232overshooting of
9233the u-component of velocity in case that the upstream-spline scheme is
9234switched on (in m/s).
9235     
9236     
9237     
9238     
9239     
9240     
9241      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9242      </p>
9243
9244
9245
9246
9247
9248
9249 
9250     
9251     
9252     
9253     
9254     
9255     
9256      <p>Only positive values are allowed for <b>overshoot_limit_u</b>.</p>
9257
9258
9259
9260
9261
9262
9263
9264      </td>
9265
9266
9267
9268
9269
9270
9271 </tr>
9272
9273
9274
9275
9276
9277
9278 <tr>
9279
9280
9281
9282
9283
9284
9285 <td style="vertical-align: top;"> 
9286     
9287     
9288     
9289     
9290     
9291     
9292      <p><a name="overshoot_limit_v"></a><b>overshoot_limit_v</b></p>
9293
9294
9295
9296
9297
9298
9299
9300      </td>
9301
9302
9303
9304
9305
9306
9307 <td style="vertical-align: top;">R</td>
9308
9309
9310
9311
9312
9313
9314
9315      <td style="vertical-align: top;"><i>0.0</i></td>
9316
9317
9318
9319
9320
9321
9322
9323      <td style="vertical-align: top;"> 
9324     
9325     
9326     
9327     
9328     
9329     
9330      <p>Allowed limit
9331for the overshooting of the v-component of
9332velocity in case that the upstream-spline scheme is switched on
9333(in m/s).&nbsp; </p>
9334
9335
9336
9337
9338
9339
9340 
9341     
9342     
9343     
9344     
9345     
9346     
9347      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9348      </p>
9349
9350
9351
9352
9353
9354
9355 
9356     
9357     
9358     
9359     
9360     
9361     
9362      <p>Only positive values are allowed for <b>overshoot_limit_v</b>.</p>
9363
9364
9365
9366
9367
9368
9369
9370      </td>
9371
9372
9373
9374
9375
9376
9377 </tr>
9378
9379
9380
9381
9382
9383
9384 <tr>
9385
9386
9387
9388
9389
9390
9391 <td style="vertical-align: top;"> 
9392     
9393     
9394     
9395     
9396     
9397     
9398      <p><a name="overshoot_limit_w"></a><b>overshoot_limit_w</b></p>
9399
9400
9401
9402
9403
9404
9405
9406      </td>
9407
9408
9409
9410
9411
9412
9413 <td style="vertical-align: top;">R</td>
9414
9415
9416
9417
9418
9419
9420
9421      <td style="vertical-align: top;"><i>0.0</i></td>
9422
9423
9424
9425
9426
9427
9428
9429      <td style="vertical-align: top;"> 
9430     
9431     
9432     
9433     
9434     
9435     
9436      <p>Allowed limit
9437for the overshooting of the w-component of
9438velocity in case that the upstream-spline scheme is switched on
9439(in m/s).&nbsp; </p>
9440
9441
9442
9443
9444
9445
9446 
9447     
9448     
9449     
9450     
9451     
9452     
9453      <p>For further information see <a href="#overshoot_limit_e">overshoot_limit_e</a>.&nbsp;
9454      </p>
9455
9456
9457
9458
9459
9460
9461 
9462     
9463     
9464     
9465     
9466     
9467     
9468      <p>Only positive values are permitted for <b>overshoot_limit_w</b>.</p>
9469
9470
9471
9472
9473
9474
9475
9476      </td>
9477
9478
9479
9480
9481
9482
9483 </tr>
9484
9485
9486
9487
9488
9489
9490 <tr>
9491
9492
9493
9494
9495
9496
9497 <td style="vertical-align: top;"> 
9498     
9499     
9500     
9501     
9502     
9503     
9504      <p><a name="passive_scalar"></a><b>passive_scalar</b></p>
9505
9506
9507
9508
9509
9510
9511
9512      </td>
9513
9514
9515
9516
9517
9518
9519 <td style="vertical-align: top;">L</td>
9520
9521
9522
9523
9524
9525
9526
9527      <td style="vertical-align: top;"><i>.F.</i></td>
9528
9529
9530
9531
9532
9533
9534
9535      <td style="vertical-align: top;"> 
9536     
9537     
9538     
9539     
9540     
9541     
9542      <p>Parameter to
9543switch on the prognostic equation for a passive
9544scalar. <br>
9545
9546
9547
9548
9549
9550
9551 </p>
9552
9553
9554
9555
9556
9557
9558 
9559     
9560     
9561     
9562     
9563     
9564     
9565      <p>The initial vertical profile
9566of s can be set via parameters <a href="#s_surface">s_surface</a>,
9567      <a href="#s_vertical_gradient">s_vertical_gradient</a>
9568and&nbsp; <a href="#s_vertical_gradient_level">s_vertical_gradient_level</a>.
9569Boundary conditions can be set via <a href="#s_surface_initial_change">s_surface_initial_change</a>
9570and <a href="#surface_scalarflux">surface_scalarflux</a>.&nbsp;
9571      </p>
9572
9573
9574
9575
9576
9577
9578 
9579     
9580     
9581     
9582     
9583     
9584     
9585      <p><b>Note:</b> <br>
9586
9587
9588
9589
9590
9591
9592
9593With <span style="font-weight: bold;">passive_scalar</span>
9594switched
9595on, the simultaneous use of humidity (see&nbsp;<a href="#humidity">humidity</a>)
9596is impossible.</p>
9597
9598
9599
9600
9601
9602
9603 </td>
9604
9605
9606
9607
9608
9609
9610 </tr>
9611
9612
9613
9614
9615
9616
9617 <tr>
9618
9619      <td style="vertical-align: top;"><a name="pch_index"></a><span style="font-weight: bold;">pch_index</span></td>
9620
9621      <td style="vertical-align: top;">I</td>
9622
9623      <td style="vertical-align: top;"><span style="font-style: italic;">0</span></td>
9624
9625      <td style="vertical-align: top;">Grid point index (scalar) of the upper boundary of the plant canopy layer.<br>
9626
9627      <br>
9628
9629Above <span style="font-weight: bold;">pch_index</span> the arrays of leaf area density and drag_coeffient are automatically set to zero in case of <a href="#plant_canopy">plant_canopy</a> = .T.. Up to <span style="font-weight: bold;">pch_index</span> a leaf area density profile can be prescribed by using the parameters <a href="#lad_surface">lad_surface</a>, <a href="#lad_vertical_gradient">lad_vertical_gradient</a> and <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>.</td>
9630
9631    </tr>
9632
9633    <tr>
9634
9635
9636
9637
9638
9639
9640 <td style="vertical-align: top;"> 
9641     
9642     
9643     
9644     
9645     
9646     
9647      <p><a name="phi"></a><b>phi</b></p>
9648
9649
9650
9651
9652
9653
9654
9655      </td>
9656
9657
9658
9659
9660
9661
9662 <td style="vertical-align: top;">R</td>
9663
9664
9665
9666
9667
9668
9669
9670      <td style="vertical-align: top;"><i>55.0</i></td>
9671
9672
9673
9674
9675
9676
9677
9678      <td style="vertical-align: top;"> 
9679     
9680     
9681     
9682     
9683     
9684     
9685      <p>Geographical
9686latitude (in degrees).&nbsp; </p>
9687
9688
9689
9690
9691
9692
9693 
9694     
9695     
9696     
9697     
9698     
9699     
9700      <p>The value of
9701this parameter determines the value of the
9702Coriolis parameters f and f*, provided that the angular velocity (see <a href="#omega">omega</a>)
9703is non-zero.</p>
9704
9705
9706
9707
9708
9709
9710 </td>
9711
9712
9713
9714
9715
9716
9717 </tr>
9718
9719
9720
9721
9722
9723
9724 <tr>
9725
9726      <td style="vertical-align: top;"><a name="plant_canopy"></a><span style="font-weight: bold;">plant_canopy</span></td>
9727
9728      <td style="vertical-align: top;">L</td>
9729
9730      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9731
9732      <td style="vertical-align: top;">Switch for the plant_canopy_model.<br>
9733
9734      <br>
9735
9736If <span style="font-weight: bold;">plant_canopy</span> is set <span style="font-style: italic;">.T.</span>, the plant canopy model of Watanabe (2004, BLM 112, 307-341) is used. <br>
9737
9738The
9739impact of a plant canopy on a turbulent flow is considered by an
9740additional drag term in the momentum equations and an additional sink
9741term in the prognostic equation for the subgrid-scale TKE. These
9742additional terms are dependent on the leaf drag coefficient (see <a href="#drag_coefficient">drag_coefficient</a>) and the leaf area density (see <a href="#lad_surface">lad_surface</a>, <a href="#lad_vertical_gradient">lad_vertical_gradient</a>, <a href="#lad_vertical_gradient_level">lad_vertical_gradient_level</a>). The top boundary of the plant canopy is determined by the parameter <a href="#pch_index">pch_index</a>. For all heights equal to or larger than zw(k=<span style="font-weight: bold;">pch_index</span>) the leaf area density is 0 (i.e. there is no canopy at these heights!). <br>
9743
9744By default, a horizontally homogeneous plant canopy is prescribed, if&nbsp; <span style="font-weight: bold;">plant_canopy</span> is set <span style="font-style: italic;">.T.</span>. However, the user can define other types of plant canopies (see <a href="#canopy_mode">canopy_mode</a>).<br><br>If <span style="font-weight: bold;">plant_canopy</span> and&nbsp; <span style="font-weight: bold;">passive_scalar</span><span style="font-style: italic;"> </span>are set <span style="font-style: italic;">.T.</span>,
9745the canopy acts as an additional source or sink, respectively, of
9746scalar concentration. The source/sink strength is dependent on the
9747scalar concentration at the leaf surface, which is generally constant
9748with time in PALM and which can be specified by specifying the
9749parameter <a href="#leaf_surface_concentration">leaf_surface_concentration</a>. <br><br>Additional heating of the air by the plant canopy is taken into account, when the default value of the parameter <a href="#cthf">cthf</a> is altered in the parameter file. In that case the value of <a href="#surface_heatflux">surface_heatflux</a>
9750specified in the parameter file is not used in the model. Instead the
9751near-surface heat flux is derived from an expontial function that is
9752dependent on the cumulative leaf area index. <br> 
9753
9754      <br>
9755
9756      <span style="font-weight: bold;">plant_canopy</span> = <span style="font-style: italic;">.T. </span>is only allowed together with a non-zero <a href="#drag_coefficient">drag_coefficient</a>.</td>
9757
9758    </tr>
9759
9760    <tr>
9761
9762
9763
9764
9765
9766
9767 <td style="vertical-align: top;"> 
9768     
9769     
9770     
9771     
9772     
9773     
9774      <p><a name="prandtl_layer"></a><b>prandtl_layer</b></p>
9775
9776
9777
9778
9779
9780
9781
9782      </td>
9783
9784
9785
9786
9787
9788
9789 <td style="vertical-align: top;">L</td>
9790
9791
9792
9793
9794
9795
9796
9797      <td style="vertical-align: top;"><i>.T.</i></td>
9798
9799
9800
9801
9802
9803
9804
9805      <td style="vertical-align: top;"> 
9806     
9807     
9808     
9809     
9810     
9811     
9812      <p>Parameter to
9813switch on a Prandtl layer.&nbsp; </p>
9814
9815
9816
9817
9818
9819
9820 
9821     
9822     
9823     
9824     
9825     
9826     
9827      <p>By default,
9828a Prandtl layer is switched on at the bottom
9829boundary between z = 0 and z = 0.5 * <a href="#dz">dz</a>
9830(the first computational grid point above ground for u, v and the
9831scalar quantities).
9832In this case, at the bottom boundary, free-slip conditions for u and v
9833(see <a href="#bc_uv_b">bc_uv_b</a>)
9834are not allowed. Likewise, laminar
9835simulations with constant eddy diffusivities (<a href="#km_constant">km_constant</a>)
9836are forbidden.&nbsp; </p>
9837
9838
9839
9840
9841
9842
9843 
9844     
9845     
9846     
9847     
9848     
9849     
9850      <p>With Prandtl-layer
9851switched off, the TKE boundary condition <a href="#bc_e_b">bc_e_b</a>
9852= '<i>(u*)**2+neumann'</i> must not be used and is
9853automatically
9854changed to <i>'neumann'</i> if necessary.&nbsp; Also,
9855the pressure
9856boundary condition <a href="#bc_p_b">bc_p_b</a>
9857= <i>'neumann+inhomo'</i>&nbsp; is not allowed. </p>
9858
9859
9860
9861
9862
9863
9864
9865     
9866     
9867     
9868     
9869     
9870     
9871      <p>The roughness length is declared via the parameter <a href="#roughness_length">roughness_length</a>.</p>
9872
9873
9874
9875
9876
9877
9878
9879      </td>
9880
9881
9882
9883
9884
9885
9886 </tr>
9887
9888
9889
9890
9891
9892
9893 <tr>
9894
9895
9896
9897
9898
9899
9900 <td style="vertical-align: top;"> 
9901     
9902     
9903     
9904     
9905     
9906     
9907      <p><a name="precipitation"></a><b>precipitation</b></p>
9908
9909
9910
9911
9912
9913
9914
9915      </td>
9916
9917
9918
9919
9920
9921
9922 <td style="vertical-align: top;">L</td>
9923
9924
9925
9926
9927
9928
9929
9930      <td style="vertical-align: top;"><span style="font-style: italic;">.F.</span></td>
9931
9932
9933
9934
9935
9936
9937 <td style="vertical-align: top;"> 
9938     
9939     
9940     
9941     
9942     
9943     
9944      <p>Parameter to switch
9945on the precipitation scheme.<br>
9946
9947
9948
9949
9950
9951
9952 </p>
9953
9954
9955
9956
9957
9958
9959 
9960     
9961     
9962     
9963     
9964     
9965     
9966      <p>For
9967precipitation processes PALM uses a simplified Kessler
9968scheme. This scheme only considers the
9969so-called autoconversion, that means the generation of rain water by
9970coagulation of cloud drops among themselves. Precipitation begins and
9971is immediately removed from the flow as soon as the liquid water
9972content exceeds the critical value of 0.5 g/kg.</p>
9973
9974
9975
9976
9977
9978
9979     
9980     
9981     
9982     
9983     
9984     
9985      <p>The precipitation rate and amount can be output by assigning the runtime parameter <a href="chapter_4.2.html#data_output">data_output</a> = <span style="font-style: italic;">'prr*'</span> or <span style="font-style: italic;">'pra*'</span>, respectively. The time interval on which the precipitation amount is defined can be controlled via runtime parameter <a href="chapter_4.2.html#precipitation_amount_interval">precipitation_amount_interval</a>.</p>
9986
9987
9988
9989
9990
9991
9992 </td>
9993
9994
9995
9996
9997
9998
9999 </tr>
10000
10001
10002
10003
10004
10005
10006
10007    <tr>
10008
10009
10010
10011
10012
10013
10014      <td style="vertical-align: top;"><a name="pt_reference"></a><span style="font-weight: bold;">pt_reference</span></td>
10015
10016
10017
10018
10019
10020
10021      <td style="vertical-align: top;">R</td>
10022
10023
10024
10025
10026
10027
10028      <td style="vertical-align: top;"><span style="font-style: italic;">use horizontal average as
10029refrence</span></td>
10030
10031
10032
10033
10034
10035
10036      <td style="vertical-align: top;">Reference
10037temperature to be used in all buoyancy terms (in K).<br>
10038
10039
10040
10041
10042
10043
10044      <br>
10045
10046
10047
10048
10049
10050
10051By
10052default, the instantaneous horizontal average over the total model
10053domain is used.<br>
10054
10055
10056
10057
10058
10059
10060      <br>
10061
10062
10063
10064
10065
10066
10067      <span style="font-weight: bold;">Attention:</span><br>
10068
10069
10070
10071
10072
10073
10074In case of ocean runs (see <a href="chapter_4.1.html#ocean">ocean</a>), always a reference temperature is used in the buoyancy terms with a default value of <span style="font-weight: bold;">pt_reference</span> = <a href="#pt_surface">pt_surface</a>.</td>
10075
10076
10077
10078
10079
10080
10081    </tr>
10082
10083
10084
10085
10086
10087
10088    <tr>
10089
10090
10091
10092
10093
10094
10095 <td style="vertical-align: top;"> 
10096     
10097     
10098     
10099     
10100     
10101     
10102      <p><a name="pt_surface"></a><b>pt_surface</b></p>
10103
10104
10105
10106
10107
10108
10109
10110      </td>
10111
10112
10113
10114
10115
10116
10117 <td style="vertical-align: top;">R</td>
10118
10119
10120
10121
10122
10123
10124
10125      <td style="vertical-align: top;"><i>300.0</i></td>
10126
10127
10128
10129
10130
10131
10132
10133      <td style="vertical-align: top;"> 
10134     
10135     
10136     
10137     
10138     
10139     
10140      <p>Surface
10141potential temperature (in K).&nbsp; </p>
10142
10143
10144
10145
10146
10147
10148 
10149     
10150     
10151     
10152     
10153     
10154     
10155      <p>This
10156parameter assigns the value of the potential temperature
10157      <span style="font-weight: bold;">pt</span> at the surface (k=0)<b>.</b> Starting from this value,
10158the
10159initial vertical temperature profile is constructed with <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10160and <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level
10161      </a>.
10162This profile is also used for the 1d-model as a stationary profile.</p>
10163
10164
10165
10166
10167
10168
10169     
10170     
10171     
10172     
10173     
10174     
10175      <p><span style="font-weight: bold;">Attention:</span><br>
10176
10177
10178
10179
10180
10181
10182In case of ocean runs (see <a href="#ocean">ocean</a>),
10183this parameter gives the temperature value at the sea surface, which is
10184at k=nzt. The profile is then constructed from the surface down to the
10185bottom of the model.</p>
10186
10187
10188
10189
10190
10191
10192
10193      </td>
10194
10195
10196
10197
10198
10199
10200 </tr>
10201
10202
10203
10204
10205
10206
10207 <tr>
10208
10209
10210
10211
10212
10213
10214 <td style="vertical-align: top;"> 
10215     
10216     
10217     
10218     
10219     
10220     
10221      <p><a name="pt_surface_initial_change"></a><b>pt_surface_initial</b>
10222      <br>
10223
10224
10225
10226
10227
10228
10229 <b>_change</b></p>
10230
10231
10232
10233
10234
10235
10236 </td>
10237
10238
10239
10240
10241
10242
10243 <td style="vertical-align: top;">R</td>
10244
10245
10246
10247
10248
10249
10250 <td style="vertical-align: top;"><span style="font-style: italic;">0.0</span><br>
10251
10252
10253
10254
10255
10256
10257 </td>
10258
10259
10260
10261
10262
10263
10264
10265      <td style="vertical-align: top;"> 
10266     
10267     
10268     
10269     
10270     
10271     
10272      <p>Change in
10273surface temperature to be made at the beginning of
10274the 3d run
10275(in K).&nbsp; </p>
10276
10277
10278
10279
10280
10281
10282 
10283     
10284     
10285     
10286     
10287     
10288     
10289      <p>If <b>pt_surface_initial_change</b>
10290is set to a non-zero
10291value, the near surface sensible heat flux is not allowed to be given
10292simultaneously (see <a href="#surface_heatflux">surface_heatflux</a>).</p>
10293
10294
10295
10296
10297
10298
10299
10300      </td>
10301
10302
10303
10304
10305
10306
10307 </tr>
10308
10309
10310
10311
10312
10313
10314 <tr>
10315
10316
10317
10318
10319
10320
10321 <td style="vertical-align: top;"> 
10322     
10323     
10324     
10325     
10326     
10327     
10328      <p><a name="pt_vertical_gradient"></a><b>pt_vertical_gradient</b></p>
10329
10330
10331
10332
10333
10334
10335
10336      </td>
10337
10338
10339
10340
10341
10342
10343 <td style="vertical-align: top;">R (10)</td>
10344
10345
10346
10347
10348
10349
10350
10351      <td style="vertical-align: top;"><i>10 * 0.0</i></td>
10352
10353
10354
10355
10356
10357
10358
10359      <td style="vertical-align: top;"> 
10360     
10361     
10362     
10363     
10364     
10365     
10366      <p>Temperature
10367gradient(s) of the initial temperature profile (in
10368K
10369/ 100 m).&nbsp; </p>
10370
10371
10372
10373
10374
10375
10376 
10377     
10378     
10379     
10380     
10381     
10382     
10383      <p>This temperature gradient
10384holds starting from the height&nbsp;
10385level defined by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>
10386(precisely: for all uv levels k where zu(k) &gt;
10387pt_vertical_gradient_level,
10388pt_init(k) is set: pt_init(k) = pt_init(k-1) + dzu(k) * <b>pt_vertical_gradient</b>)
10389up to the top boundary or up to the next height level defined
10390by <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>.
10391A total of 10 different gradients for 11 height intervals (10 intervals
10392if <a href="#pt_vertical_gradient_level">pt_vertical_gradient_level</a>(1)
10393= <i>0.0</i>) can be assigned. The surface temperature is
10394assigned via <a href="#pt_surface">pt_surface</a>.&nbsp;
10395      </p>
10396
10397
10398
10399
10400
10401
10402 
10403     
10404     
10405     
10406     
10407     
10408     
10409      <p>Example:&nbsp; </p>
10410
10411
10412
10413
10414
10415
10416 
10417     
10418     
10419     
10420     
10421     
10422     
10423      <ul>
10424
10425
10426
10427
10428
10429
10430 
10431       
10432       
10433       
10434       
10435       
10436       
10437        <p><b>pt_vertical_gradient</b>
10438= <i>1.0</i>, <i>0.5</i>,&nbsp; <br>
10439
10440
10441
10442
10443
10444
10445
10446        <b>pt_vertical_gradient_level</b> = <i>500.0</i>,
10447        <i>1000.0</i>,</p>
10448
10449
10450
10451
10452
10453
10454 
10455     
10456     
10457     
10458     
10459     
10460     
10461      </ul>
10462
10463
10464
10465
10466
10467
10468 
10469     
10470     
10471     
10472     
10473     
10474     
10475      <p>That
10476defines the temperature profile to be neutrally
10477stratified
10478up to z = 500.0 m with a temperature given by <a href="#pt_surface">pt_surface</a>.
10479For 500.0 m &lt; z &lt;= 1000.0 m the temperature gradient is
104801.0 K /
10481100 m and for z &gt; 1000.0 m up to the top boundary it is
104820.5 K / 100 m (it is assumed that the assigned height levels correspond
10483with uv levels).</p>
10484
10485
10486
10487
10488
10489
10490     
10491     
10492     
10493     
10494     
10495     
10496      <p><span style="font-weight: bold;">Attention:</span><br>
10497
10498
10499
10500
10501
10502
10503In case of ocean runs (see <a href="chapter_4.1.html#ocean">ocean</a>),
10504the profile is constructed like described above, but starting from the
10505sea surface (k=nzt) down to the bottom boundary of the model. Height
10506levels have then to be given as negative values, e.g. <span style="font-weight: bold;">pt_vertical_gradient_level</span> = <span style="font-style: italic;">-500.0</span>, <span style="font-style: italic;">-1000.0</span>.</p>
10507
10508
10509
10510
10511
10512
10513 </td>
10514
10515
10516
10517
10518
10519
10520 </tr>
10521
10522
10523
10524
10525
10526
10527 <tr>
10528
10529
10530
10531
10532
10533
10534 <td style="vertical-align: top;"> 
10535     
10536     
10537     
10538     
10539     
10540     
10541      <p><a name="pt_vertical_gradient_level"></a><b>pt_vertical_gradient</b>
10542      <br>
10543
10544
10545
10546
10547
10548
10549 <b>_level</b></p>
10550
10551
10552
10553
10554
10555
10556 </td>
10557
10558
10559
10560
10561
10562
10563 <td style="vertical-align: top;">R (10)</td>
10564
10565
10566
10567
10568
10569
10570 <td style="vertical-align: top;"> 
10571     
10572     
10573     
10574     
10575     
10576     
10577      <p><i>10 *</i>&nbsp;
10578      <span style="font-style: italic;">0.0</span><br>
10579
10580
10581
10582
10583
10584
10585
10586      </p>
10587
10588
10589
10590
10591
10592
10593 </td>
10594
10595
10596
10597
10598
10599
10600 <td style="vertical-align: top;">
10601     
10602     
10603     
10604     
10605     
10606     
10607      <p>Height level from which on the temperature gradient defined by
10608      <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10609is effective (in m).&nbsp; </p>
10610
10611
10612
10613
10614
10615
10616 
10617     
10618     
10619     
10620     
10621     
10622     
10623      <p>The height levels have to be assigned in ascending order. The
10624default values result in a neutral stratification regardless of the
10625values of <a href="#pt_vertical_gradient">pt_vertical_gradient</a>
10626(unless the top boundary of the model is higher than 100000.0 m).
10627For the piecewise construction of temperature profiles see <a href="#pt_vertical_gradient">pt_vertical_gradient</a>.</p>
10628
10629
10630
10631
10632
10633
10634      <span style="font-weight: bold;">Attention:</span><br>
10635
10636
10637
10638
10639
10640
10641In case of ocean runs&nbsp;(see <a href="chapter_4.1.html#ocean">ocean</a>), the (negative) height levels have to be assigned in descending order.
10642      </td>
10643
10644
10645
10646
10647
10648
10649 </tr>
10650
10651
10652
10653
10654
10655
10656 <tr>
10657
10658
10659
10660
10661
10662
10663 <td style="vertical-align: top;"> 
10664     
10665     
10666     
10667     
10668     
10669     
10670      <p><a name="q_surface"></a><b>q_surface</b></p>
10671
10672
10673
10674
10675
10676
10677
10678      </td>
10679
10680
10681
10682
10683
10684
10685 <td style="vertical-align: top;">R</td>
10686
10687
10688
10689
10690
10691
10692
10693      <td style="vertical-align: top;"><i>0.0</i></td>
10694
10695
10696
10697
10698
10699
10700
10701      <td style="vertical-align: top;"> 
10702     
10703     
10704     
10705     
10706     
10707     
10708      <p>Surface
10709specific humidity / total water content (kg/kg).&nbsp; </p>
10710
10711
10712
10713
10714
10715
10716 
10717     
10718     
10719     
10720     
10721     
10722     
10723      <p>This
10724parameter assigns the value of the specific humidity q at
10725the surface (k=0).&nbsp; Starting from this value, the initial
10726humidity
10727profile is constructed with&nbsp; <a href="#q_vertical_gradient">q_vertical_gradient</a>
10728and <a href="#q_vertical_gradient_level">q_vertical_gradient_level</a>.
10729This profile is also used for the 1d-model as a stationary profile.</p>
10730
10731
10732
10733
10734
10735
10736
10737      </td>
10738
10739
10740
10741
10742
10743
10744 </tr>
10745
10746
10747
10748
10749
10750
10751 <tr>
10752
10753
10754
10755
10756
10757
10758 <td style="vertical-align: top;"> 
10759     
10760     
10761     
10762     
10763     
10764     
10765      <p><a name="q_surface_initial_change"></a><b>q_surface_initial</b>
10766      <br>
10767
10768
10769
10770
10771
10772
10773 <b>_change</b></p>
10774
10775
10776
10777
10778
10779
10780 </td>
10781
10782
10783
10784
10785
10786
10787 <td style=