Home

Context Navigation

source: palm/trunk/SOURCE/init_grid.f90 @ 1983

Last change on this file since 1983 was 1983, checked in by suehring, 8 years ago
last commit documented
Property svn:keywords set to `Id`
File size: 61.8 KB

Rev	Line
[1682]	1	!> @file init_grid.f90
[1743]	2	!-------------------------------------------------------------------------------!
[1036]	3	! This file is part of PALM.
	4	!
	5	! PALM is free software: you can redistribute it and/or modify it under the terms
	6	! of the GNU General Public License as published by the Free Software Foundation,
	7	! either version 3 of the License, or (at your option) any later version.
	8	!
	9	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
	10	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
	11	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
	12	!
	13	! You should have received a copy of the GNU General Public License along with
	14	! PALM. If not, see <http://www.gnu.org/licenses/>.
	15	!
[1818]	16	! Copyright 1997-2016 Leibniz Universitaet Hannover
[1743]	17	!-------------------------------------------------------------------------------!
[1036]	18	!
[254]	19	! Current revisions:
[1]	20	! -----------------
[1969]	21	!
[1983]	22	!
[1969]	23	! Former revisions:
	24	! -----------------
	25	! $Id: init_grid.f90 1983 2016-08-01 11:06:41Z suehring $
	26	!
[1983]	27	! 1982 2016-08-01 11:04:48Z suehring
	28	! Bugfix concering consistency check for topography
	29	!
[1969]	30	! 1968 2016-07-18 12:01:49Z suehring
[1968]	31	! Changed: PE-wise reading of topography file in order to avoid global definition
	32	! of arrays nzb_local and nzb_tmp. Thereby, topography definition for single
	33	! buildings and street canyons has changed, as well as flag setting for
	34	! multigrid scheme.
	35	!
	36	! Bugfix in checking l_grid anisotropy.
	37	! Simplify initial computation of lwall and vertical_influence, i.e. remove
	38	! nzb_s_inner as it is still zero at this point.
[1932]	39	!
[1943]	40	! 1942 2016-06-14 12:18:18Z suehring
	41	! Topography filter implemented to fill holes resolved by only one grid point.
	42	! Initialization of flags for ws-scheme moved to advec_ws.
	43	!
[1932]	44	! 1931 2016-06-10 12:06:59Z suehring
	45	! Rename multigrid into multigrid_noopt and multigrid_fast into multigrid
	46	!
[1911]	47	! 1910 2016-05-26 06:49:46Z raasch
	48	! Bugfix: if topography is read from file, Neumann conditions are used for the
	49	! nzb_local array (instead of cyclic conditions) in case that non-cyclic
	50	! boundary conditions are switched on for the run
	51	!
[1903]	52	! 1902 2016-05-09 11:18:56Z suehring
[1910]	53	! Set topography flags for multigrid solver only (not for multigrid_fast)
[1903]	54	!
[1887]	55	! 1886 2016-04-21 11:20:47Z suehring
	56	! Bugfix: setting advection flags near walls
	57	! reformulated index values for nzb_v_inner
	58	! variable discriptions added in declaration block
	59	!
[1846]	60	! 1845 2016-04-08 08:29:13Z raasch
	61	! nzb_2d removed
	62	!
[1805]	63	! 1804 2016-04-05 16:30:18Z maronga
	64	! Removed code for parameter file check (__check)
	65	!
[1780]	66	! 1779 2016-03-03 08:01:28Z raasch
	67	! coupling_char is trimmed at every place it occurs, because it can have
	68	! different length now
	69	!
[1763]	70	! 1762 2016-02-25 12:31:13Z hellstea
	71	! Introduction of nested domain feature
	72	!
[1744]	73	! 1743 2016-01-13 10:23:51Z raasch
	74	! Bugfix for calculation of nzb_s_outer and nzb_u_outer at north boundary of
	75	! total domain
	76	!
[1692]	77	! 1691 2015-10-26 16:17:44Z maronga
	78	! Renamed prandtl_layer to constant_flux_layer.
	79	!
[1683]	80	! 1682 2015-10-07 23:56:08Z knoop
	81	! Code annotations made doxygen readable
	82	!
[1678]	83	! 1677 2015-10-02 13:25:23Z boeske
	84	! Bugfix: Ghost points are included in wall_flags_0 and wall_flags_00
	85	!
[1676]	86	! 1675 2015-10-02 08:28:59Z gronemeier
	87	! Bugfix: Definition of topography grid levels
	88	!
[1662]	89	! 1660 2015-09-21 08:15:16Z gronemeier
	90	! Bugfix: Definition of topography grid levels if vertical grid stretching
	91	! starts below the maximum topography height.
	92	!
[1581]	93	! 1580 2015-04-10 13:43:49Z suehring
	94	! Bugfix: setting flags for 5th order scheme near buildings
	95	!
[1576]	96	! 1575 2015-03-27 09:56:27Z raasch
	97	! adjustments for psolver-queries
	98	!
[1558]	99	! 1557 2015-03-05 16:43:04Z suehring
	100	! Adjustment for monotoinic limiter
	101	!
[1419]	102	! 1418 2014-06-06 13:05:08Z fricke
	103	! Bugfix: Change if-condition for stretched grid in the ocean, with the old
	104	! condition and a negative value for dz_stretch_level the condition
	105	! was always true for the whole model domain
	106	!
[1410]	107	! 1409 2014-05-23 12:11:32Z suehring
	108	! Bugfix: set wall_flags_0 at inflow and outflow boundary also for i <= nxlu
	109	! j <= nysv
	110	!
[1354]	111	! 1353 2014-04-08 15:21:23Z heinze
	112	! REAL constants provided with KIND-attribute
	113	!
[1323]	114	! 1322 2014-03-20 16:38:49Z raasch
	115	! REAL constants defined as wp-kind
	116	!
[1321]	117	! 1320 2014-03-20 08:40:49Z raasch
[1320]	118	! ONLY-attribute added to USE-statements,
	119	! kind-parameters added to all INTEGER and REAL declaration statements,
	120	! kinds are defined in new module kinds,
	121	! revision history before 2012 removed,
	122	! comment fields (!:) to be used for variable explanations added to
	123	! all variable declaration statements
[1321]	124	!
[1222]	125	! 1221 2013-09-10 08:59:13Z raasch
	126	! wall_flags_00 introduced to hold bits 32-63,
	127	! additional 3D-flag arrays for replacing the 2D-index array nzb_s_inner in
	128	! loops optimized for openACC (pres + flow_statistics)
	129	!
[1093]	130	! 1092 2013-02-02 11:24:22Z raasch
	131	! unused variables removed
	132	!
[1070]	133	! 1069 2012-11-28 16:18:43Z maronga
[1779]	134	! bugfix: added coupling_char to TOPOGRAPHY_DATA to allow topography in the
	135	! ocean model in case of coupled runs
[1070]	136	!
[1037]	137	! 1036 2012-10-22 13:43:42Z raasch
	138	! code put under GPL (PALM 3.9)
	139	!
[1017]	140	! 1015 2012-09-27 09:23:24Z raasch
	141	! lower index for calculating wall_flags_0 set to nzb_w_inner instead of
	142	! nzb_w_inner+1
	143	!
[997]	144	! 996 2012-09-07 10:41:47Z raasch
	145	! little reformatting
	146	!
[979]	147	! 978 2012-08-09 08:28:32Z fricke
	148	! Bugfix: nzb_max is set to nzt at non-cyclic lateral boundaries
	149	! Bugfix: Set wall_flags_0 for inflow boundary
	150	!
[928]	151	! 927 2012-06-06 19:15:04Z raasch
	152	! Wall flags are not set for multigrid method in case of masking method
	153	!
[865]	154	! 864 2012-03-27 15:10:33Z gryschka
[927]	155	! In case of ocean and Dirichlet bottom bc for u and v dzu_mg and ddzu_pres
	156	! were not correctly defined for k=1.
[865]	157	!
[863]	158	! 861 2012-03-26 14:18:34Z suehring
[861]	159	! Set wall_flags_0. The array is needed for degradation in ws-scheme near walls,
	160	! inflow and outflow boundaries as well as near the bottom and the top of the
[863]	161	! model domain.!
[861]	162	! Initialization of nzb_s_inner and nzb_w_inner.
	163	! gls has to be at least nbgp to do not exceed the array bounds of nzb_local
	164	! while setting wall_flags_0
	165	!
[844]	166	! 843 2012-02-29 15:16:21Z gryschka
	167	! In case of ocean and dirichlet bc for u and v at the bottom
	168	! the first u-level ist defined at same height as the first w-level
	169	!
[819]	170	! 818 2012-02-08 16:11:23Z maronga
	171	! Bugfix: topo_height is only required if topography is used. It is thus now
	172	! allocated in the topography branch
	173	!
[810]	174	! 809 2012-01-30 13:32:58Z maronga
	175	! Bugfix: replaced .AND. and .NOT. with && and ! in the preprocessor directives
	176	!
[808]	177	! 807 2012-01-25 11:53:51Z maronga
	178	! New cpp directive "__check" implemented which is used by check_namelist_files
	179	!
[1]	180	! Revision 1.1 1997/08/11 06:17:45 raasch
	181	! Initial revision (Testversion)
	182	!
	183	!
	184	! Description:
	185	! ------------
[1682]	186	!> Creating grid depending constants
[1]	187	!------------------------------------------------------------------------------!
[1682]	188	SUBROUTINE init_grid
	189
[1942]	190	USE advec_ws, &
	191	ONLY: ws_init_flags
[1]	192
[1320]	193	USE arrays_3d, &
	194	ONLY: dd2zu, ddzu, ddzu_pres, ddzw, dzu, dzu_mg, dzw, dzw_mg, f1_mg, &
	195	f2_mg, f3_mg, l_grid, l_wall, zu, zw
	196
[1353]	197	USE control_parameters, &
[1910]	198	ONLY: bc_lr_cyc, bc_ns_cyc, building_height, building_length_x, &
[1320]	199	building_length_y, building_wall_left, building_wall_south, &
	200	canyon_height, canyon_wall_left, canyon_wall_south, &
[1691]	201	canyon_width_x, canyon_width_y, constant_flux_layer, &
	202	coupling_char, dp_level_ind_b, dz, dz_max, dz_stretch_factor, &
[1968]	203	dz_stretch_level, dz_stretch_level_index, grid_level, ibc_uv_b, &
	204	io_blocks, io_group, inflow_l, inflow_n, inflow_r, inflow_s, &
[1691]	205	masking_method, maximum_grid_level, message_string, &
[1942]	206	momentum_advec, nest_domain, ocean, outflow_l, outflow_n, &
[1762]	207	outflow_r, outflow_s, psolver, scalar_advec, topography, &
[1691]	208	topography_grid_convention, use_surface_fluxes, use_top_fluxes, &
	209	wall_adjustment_factor
[1320]	210
	211	USE grid_variables, &
	212	ONLY: ddx, ddx2, ddx2_mg, ddy, ddy2, ddy2_mg, dx, dx2, dy, dy2, fwxm, &
	213	fwxp, fwym, fwyp, fxm, fxp, fym, fyp, wall_e_x, wall_e_y, &
	214	wall_u, wall_v, wall_w_x, wall_w_y, zu_s_inner, zw_w_inner
	215
	216	USE indices, &
[1942]	217	ONLY: flags, nbgp, nx, nxl, nxlg, nxl_mg, nxr, nxrg, nxr_mg, &
	218	ny, nyn, nyng, nyn_mg, nys, nys_mg, nysg, nz, nzb, &
[1845]	219	nzb_diff, nzb_diff_s_inner, nzb_diff_s_outer, nzb_diff_u, &
	220	nzb_diff_v, nzb_max, nzb_s_inner, nzb_s_outer, nzb_u_inner, &
	221	nzb_u_outer, nzb_v_inner, nzb_v_outer, nzb_w_inner, &
	222	nzb_w_outer, nzt, nzt_diff, nzt_mg, rflags_invers, &
[1320]	223	rflags_s_inner, wall_flags_0, wall_flags_00, wall_flags_1, &
	224	wall_flags_10, wall_flags_2, wall_flags_3, wall_flags_4, &
	225	wall_flags_5, wall_flags_6, wall_flags_7, wall_flags_8, &
	226	wall_flags_9
	227
	228	USE kinds
	229
[1]	230	USE pegrid
	231
	232	IMPLICIT NONE
	233
[1968]	234	INTEGER(iwp) :: bh !< temporary vertical index of building height
	235	INTEGER(iwp) :: blx !< grid point number of building size along x
	236	INTEGER(iwp) :: bly !< grid point number of building size along y
	237	INTEGER(iwp) :: bxl !< index for left building wall
	238	INTEGER(iwp) :: bxr !< index for right building wall
	239	INTEGER(iwp) :: byn !< index for north building wall
	240	INTEGER(iwp) :: bys !< index for south building wall
	241	INTEGER(iwp) :: ch !< temporary vertical index for canyon height
	242	INTEGER(iwp) :: cwx !< grid point number of canyon size along x
	243	INTEGER(iwp) :: cwy !< grid point number of canyon size along y
	244	INTEGER(iwp) :: cxl !< index for left canyon wall
	245	INTEGER(iwp) :: cxr !< index for right canyon wall
	246	INTEGER(iwp) :: cyn !< index for north canyon wall
	247	INTEGER(iwp) :: cys !< index for south canyon wall
	248	INTEGER(iwp) :: i !< index variable along x
	249	INTEGER(iwp) :: ii !< loop variable for reading topography file
	250	INTEGER(iwp) :: inc !< incremental parameter for coarsening grid level
	251	INTEGER(iwp) :: j !< index variable along y
	252	INTEGER(iwp) :: k !< index variable along z
	253	INTEGER(iwp) :: l !< loop variable
	254	INTEGER(iwp) :: nxl_l !< index of left PE boundary for multigrid level
	255	INTEGER(iwp) :: nxr_l !< index of right PE boundary for multigrid level
	256	INTEGER(iwp) :: nyn_l !< index of north PE boundary for multigrid level
	257	INTEGER(iwp) :: nys_l !< index of south PE boundary for multigrid level
	258	INTEGER(iwp) :: nzb_local_max !< vertical grid index of maximum topography height
	259	INTEGER(iwp) :: nzb_local_min !< vertical grid index of minimum topography height
	260	INTEGER(iwp) :: nzb_si !< dummy index for local nzb_s_inner
	261	INTEGER(iwp) :: nzt_l !< index of top PE boundary for multigrid level
	262	INTEGER(iwp) :: num_hole !< number of holes (in topography) resolved by only one grid point
	263	INTEGER(iwp) :: num_hole_l !< number of holes (in topography) resolved by only one grid point on local PE
	264	INTEGER(iwp) :: num_wall !< number of surrounding vertical walls for a single grid point
	265	INTEGER(iwp) :: skip_n_rows !< counting variable to skip rows while reading topography file
	266	INTEGER(iwp) :: vi !< dummy for vertical influence
[1]	267
[1886]	268	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: &
[1931]	269	vertical_influence !< number of vertical grid points above obstacle where adjustment of near-wall mixing length is required
[1886]	270
[1968]	271	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: corner_nl !< index of north-left corner location to limit near-wall mixing length
	272	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: corner_nr !< north-right
	273	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: corner_sl !< south-left
	274	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: corner_sr !< south-right
	275	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nzb_local !< index for topography top at cell-center
	276	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nzb_tmp !< dummy to calculate topography indices on u- and v-grid
	277	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: wall_l !< distance to adjacent left-facing wall
	278	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: wall_n !< north-facing
	279	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: wall_r !< right-facing
	280	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: wall_s !< right-facing
[1]	281
[1968]	282	REAL(wp) :: dum !< dummy variable to skip columns while reading topography file
[1886]	283	REAL(wp) :: dx_l !< grid spacing along x on different multigrid level
	284	REAL(wp) :: dy_l !< grid spacing along y on different multigrid level
	285	REAL(wp) :: dz_stretched !< stretched vertical grid spacing
[861]	286
[1968]	287	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: topo_height !< input variable for topography height
	288	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: zu_s_inner_l !< dummy array on global scale to write topography output array
	289	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: zw_w_inner_l !< dummy array on global scale to write topography output array
[1]	290
[667]	291
[1]	292	!
[709]	293	!-- Calculation of horizontal array bounds including ghost layers
[667]	294	nxlg = nxl - nbgp
	295	nxrg = nxr + nbgp
	296	nysg = nys - nbgp
	297	nyng = nyn + nbgp
[709]	298
[667]	299	!
[1]	300	!-- Allocate grid arrays
[1353]	301	ALLOCATE( ddzu(1:nzt+1), ddzw(1:nzt+1), dd2zu(1:nzt), dzu(1:nzt+1), &
[667]	302	dzw(1:nzt+1), l_grid(1:nzt), zu(nzb:nzt+1), zw(nzb:nzt+1) )
[1]	303
	304	!
	305	!-- Compute height of u-levels from constant grid length and dz stretch factors
[1353]	306	IF ( dz == -1.0_wp ) THEN
[254]	307	message_string = 'missing dz'
	308	CALL message( 'init_grid', 'PA0200', 1, 2, 0, 6, 0 )
[1353]	309	ELSEIF ( dz <= 0.0_wp ) THEN
[254]	310	WRITE( message_string, * ) 'dz=',dz,' <= 0.0'
	311	CALL message( 'init_grid', 'PA0201', 1, 2, 0, 6, 0 )
[1]	312	ENDIF
[94]	313
[1]	314	!
[94]	315	!-- Define the vertical grid levels
	316	IF ( .NOT. ocean ) THEN
	317	!
	318	!-- Grid for atmosphere with surface at z=0 (k=0, w-grid).
[843]	319	!-- The second u-level (k=1) corresponds to the top of the
[94]	320	!-- Prandtl-layer.
[667]	321
	322	IF ( ibc_uv_b == 0 .OR. ibc_uv_b == 2 ) THEN
[1353]	323	zu(0) = 0.0_wp
	324	! zu(0) = - dz * 0.5_wp
[667]	325	ELSE
[1353]	326	zu(0) = - dz * 0.5_wp
[667]	327	ENDIF
[1353]	328	zu(1) = dz * 0.5_wp
[1]	329
[94]	330	dz_stretch_level_index = nzt+1
	331	dz_stretched = dz
	332	DO k = 2, nzt+1
	333	IF ( dz_stretch_level <= zu(k-1) .AND. dz_stretched < dz_max ) THEN
	334	dz_stretched = dz_stretched * dz_stretch_factor
	335	dz_stretched = MIN( dz_stretched, dz_max )
	336	IF ( dz_stretch_level_index == nzt+1 ) dz_stretch_level_index = k-1
	337	ENDIF
	338	zu(k) = zu(k-1) + dz_stretched
	339	ENDDO
[1]	340
	341	!
[94]	342	!-- Compute the w-levels. They are always staggered half-way between the
[843]	343	!-- corresponding u-levels. In case of dirichlet bc for u and v at the
	344	!-- ground the first u- and w-level (k=0) are defined at same height (z=0).
	345	!-- The top w-level is extrapolated linearly.
[1353]	346	zw(0) = 0.0_wp
[94]	347	DO k = 1, nzt
[1353]	348	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	349	ENDDO
[1353]	350	zw(nzt+1) = zw(nzt) + 2.0_wp * ( zu(nzt+1) - zw(nzt) )
[1]	351
[94]	352	ELSE
[1]	353	!
[843]	354	!-- Grid for ocean with free water surface is at k=nzt (w-grid).
	355	!-- In case of neumann bc at the ground the first first u-level (k=0) lies
	356	!-- below the first w-level (k=0). In case of dirichlet bc the first u- and
	357	!-- w-level are defined at same height, but staggered from the second level.
	358	!-- The second u-level (k=1) corresponds to the top of the Prandtl-layer.
[1353]	359	zu(nzt+1) = dz * 0.5_wp
	360	zu(nzt) = - dz * 0.5_wp
[94]	361
	362	dz_stretch_level_index = 0
	363	dz_stretched = dz
	364	DO k = nzt-1, 0, -1
[1418]	365	!
	366	!-- The default value of dz_stretch_level is positive, thus the first
	367	!-- condition is always true. Hence, the second condition is necessary.
	368	IF ( dz_stretch_level >= zu(k+1) .AND. dz_stretch_level <= 0.0 &
	369	.AND. dz_stretched < dz_max ) THEN
[94]	370	dz_stretched = dz_stretched * dz_stretch_factor
	371	dz_stretched = MIN( dz_stretched, dz_max )
	372	IF ( dz_stretch_level_index == 0 ) dz_stretch_level_index = k+1
	373	ENDIF
	374	zu(k) = zu(k+1) - dz_stretched
	375	ENDDO
	376
	377	!
	378	!-- Compute the w-levels. They are always staggered half-way between the
[843]	379	!-- corresponding u-levels, except in case of dirichlet bc for u and v
	380	!-- at the ground. In this case the first u- and w-level are defined at
	381	!-- same height. The top w-level (nzt+1) is not used but set for
	382	!-- consistency, since w and all scalar variables are defined up tp nzt+1.
[94]	383	zw(nzt+1) = dz
[1353]	384	zw(nzt) = 0.0_wp
[94]	385	DO k = 0, nzt
[1353]	386	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	387	ENDDO
	388
[843]	389	!
	390	!-- In case of dirichlet bc for u and v the first u- and w-level are defined
	391	!-- at same height.
	392	IF ( ibc_uv_b == 0 ) THEN
	393	zu(0) = zw(0)
	394	ENDIF
	395
[94]	396	ENDIF
	397
	398	!
[1]	399	!-- Compute grid lengths.
	400	DO k = 1, nzt+1
	401	dzu(k) = zu(k) - zu(k-1)
[1353]	402	ddzu(k) = 1.0_wp / dzu(k)
[1]	403	dzw(k) = zw(k) - zw(k-1)
[1353]	404	ddzw(k) = 1.0_wp / dzw(k)
[1]	405	ENDDO
	406
	407	DO k = 1, nzt
[1353]	408	dd2zu(k) = 1.0_wp / ( dzu(k) + dzu(k+1) )
[1]	409	ENDDO
[667]	410
	411	!
[709]	412	!-- The FFT- SOR-pressure solvers assume grid spacings of a staggered grid
	413	!-- everywhere. For the actual grid, the grid spacing at the lowest level
	414	!-- is only dz/2, but should be dz. Therefore, an additional array
	415	!-- containing with appropriate grid information is created for these
	416	!-- solvers.
[1575]	417	IF ( psolver(1:9) /= 'multigrid' ) THEN
[667]	418	ALLOCATE( ddzu_pres(1:nzt+1) )
	419	ddzu_pres = ddzu
[864]	420	ddzu_pres(1) = ddzu_pres(2) ! change for lowest level
[667]	421	ENDIF
[1]	422
	423	!
	424	!-- In case of multigrid method, compute grid lengths and grid factors for the
	425	!-- grid levels
[1575]	426	IF ( psolver(1:9) == 'multigrid' ) THEN
[1]	427
	428	ALLOCATE( ddx2_mg(maximum_grid_level), ddy2_mg(maximum_grid_level), &
	429	dzu_mg(nzb+1:nzt+1,maximum_grid_level), &
	430	dzw_mg(nzb+1:nzt+1,maximum_grid_level), &
	431	f1_mg(nzb+1:nzt,maximum_grid_level), &
	432	f2_mg(nzb+1:nzt,maximum_grid_level), &
	433	f3_mg(nzb+1:nzt,maximum_grid_level) )
	434
	435	dzu_mg(:,maximum_grid_level) = dzu
[667]	436	!
[864]	437	!-- Next line to ensure an equally spaced grid.
	438	dzu_mg(1,maximum_grid_level) = dzu(2)
[709]	439
[1]	440	dzw_mg(:,maximum_grid_level) = dzw
	441	nzt_l = nzt
	442	DO l = maximum_grid_level-1, 1, -1
[1353]	443	dzu_mg(nzb+1,l) = 2.0_wp * dzu_mg(nzb+1,l+1)
	444	dzw_mg(nzb+1,l) = 2.0_wp * dzw_mg(nzb+1,l+1)
[1]	445	nzt_l = nzt_l / 2
	446	DO k = 2, nzt_l+1
	447	dzu_mg(k,l) = dzu_mg(2k-2,l+1) + dzu_mg(2k-1,l+1)
	448	dzw_mg(k,l) = dzw_mg(2k-2,l+1) + dzw_mg(2k-1,l+1)
	449	ENDDO
	450	ENDDO
	451
	452	nzt_l = nzt
	453	dx_l = dx
	454	dy_l = dy
	455	DO l = maximum_grid_level, 1, -1
[1353]	456	ddx2_mg(l) = 1.0_wp / dx_l**2
	457	ddy2_mg(l) = 1.0_wp / dy_l**2
[1]	458	DO k = nzb+1, nzt_l
[1353]	459	f2_mg(k,l) = 1.0_wp / ( dzu_mg(k+1,l) * dzw_mg(k,l) )
	460	f3_mg(k,l) = 1.0_wp / ( dzu_mg(k,l) * dzw_mg(k,l) )
	461	f1_mg(k,l) = 2.0_wp * ( ddx2_mg(l) + ddy2_mg(l) ) + &
[1]	462	f2_mg(k,l) + f3_mg(k,l)
	463	ENDDO
	464	nzt_l = nzt_l / 2
[1353]	465	dx_l = dx_l * 2.0_wp
	466	dy_l = dy_l * 2.0_wp
[1]	467	ENDDO
	468
	469	ENDIF
	470
	471	!
	472	!-- Compute the reciprocal values of the horizontal grid lengths.
[1353]	473	ddx = 1.0_wp / dx
	474	ddy = 1.0_wp / dy
[1]	475	dx2 = dx * dx
	476	dy2 = dy * dy
[1353]	477	ddx2 = 1.0_wp / dx2
	478	ddy2 = 1.0_wp / dy2
[1]	479
	480	!
	481	!-- Compute the grid-dependent mixing length.
	482	DO k = 1, nzt
[1322]	483	l_grid(k) = ( dx * dy * dzw(k) )**0.33333333333333_wp
[1]	484	ENDDO
	485
	486	!
	487	!-- Allocate outer and inner index arrays for topography and set
[114]	488	!-- defaults.
[667]	489
[114]	490	ALLOCATE( corner_nl(nys:nyn,nxl:nxr), corner_nr(nys:nyn,nxl:nxr), &
	491	corner_sl(nys:nyn,nxl:nxr), corner_sr(nys:nyn,nxl:nxr), &
	492	wall_l(nys:nyn,nxl:nxr), wall_n(nys:nyn,nxl:nxr), &
[1968]	493	wall_r(nys:nyn,nxl:nxr), wall_s(nys:nyn,nxl:nxr) )
	494
[667]	495	ALLOCATE( fwxm(nysg:nyng,nxlg:nxrg), fwxp(nysg:nyng,nxlg:nxrg), &
	496	fwym(nysg:nyng,nxlg:nxrg), fwyp(nysg:nyng,nxlg:nxrg), &
	497	fxm(nysg:nyng,nxlg:nxrg), fxp(nysg:nyng,nxlg:nxrg), &
	498	fym(nysg:nyng,nxlg:nxrg), fyp(nysg:nyng,nxlg:nxrg), &
	499	nzb_s_inner(nysg:nyng,nxlg:nxrg), &
	500	nzb_s_outer(nysg:nyng,nxlg:nxrg), &
	501	nzb_u_inner(nysg:nyng,nxlg:nxrg), &
	502	nzb_u_outer(nysg:nyng,nxlg:nxrg), &
	503	nzb_v_inner(nysg:nyng,nxlg:nxrg), &
	504	nzb_v_outer(nysg:nyng,nxlg:nxrg), &
	505	nzb_w_inner(nysg:nyng,nxlg:nxrg), &
	506	nzb_w_outer(nysg:nyng,nxlg:nxrg), &
	507	nzb_diff_s_inner(nysg:nyng,nxlg:nxrg), &
	508	nzb_diff_s_outer(nysg:nyng,nxlg:nxrg), &
	509	nzb_diff_u(nysg:nyng,nxlg:nxrg), &
	510	nzb_diff_v(nysg:nyng,nxlg:nxrg), &
[1968]	511	nzb_local(nysg:nyng,nxlg:nxrg), &
	512	nzb_tmp(nysg:nyng,nxlg:nxrg), &
[1221]	513	rflags_s_inner(nzb:nzt+2,nysg:nyng,nxlg:nxrg), &
	514	rflags_invers(nysg:nyng,nxlg:nxrg,nzb:nzt+2), &
[667]	515	wall_e_x(nysg:nyng,nxlg:nxrg), &
	516	wall_e_y(nysg:nyng,nxlg:nxrg), &
	517	wall_u(nysg:nyng,nxlg:nxrg), &
	518	wall_v(nysg:nyng,nxlg:nxrg), &
	519	wall_w_x(nysg:nyng,nxlg:nxrg), &
	520	wall_w_y(nysg:nyng,nxlg:nxrg) )
[1]	521
	522
[667]	523
	524	ALLOCATE( l_wall(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	525
[818]	526
[1]	527	nzb_s_inner = nzb; nzb_s_outer = nzb
	528	nzb_u_inner = nzb; nzb_u_outer = nzb
	529	nzb_v_inner = nzb; nzb_v_outer = nzb
	530	nzb_w_inner = nzb; nzb_w_outer = nzb
	531
[1353]	532	rflags_s_inner = 1.0_wp
	533	rflags_invers = 1.0_wp
[1221]	534
[1]	535	!
[19]	536	!-- Define vertical gridpoint from (or to) which on the usual finite difference
[1]	537	!-- form (which does not use surface fluxes) is applied
[1691]	538	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[1]	539	nzb_diff = nzb + 2
	540	ELSE
	541	nzb_diff = nzb + 1
	542	ENDIF
[19]	543	IF ( use_top_fluxes ) THEN
	544	nzt_diff = nzt - 1
	545	ELSE
	546	nzt_diff = nzt
	547	ENDIF
[1]	548
	549	nzb_diff_s_inner = nzb_diff; nzb_diff_s_outer = nzb_diff
	550	nzb_diff_u = nzb_diff; nzb_diff_v = nzb_diff
	551
[1353]	552	wall_e_x = 0.0_wp; wall_e_y = 0.0_wp; wall_u = 0.0_wp; wall_v = 0.0_wp
	553	wall_w_x = 0.0_wp; wall_w_y = 0.0_wp
	554	fwxp = 1.0_wp; fwxm = 1.0_wp; fwyp = 1.0_wp; fwym = 1.0_wp
	555	fxp = 1.0_wp; fxm = 1.0_wp; fyp = 1.0_wp; fym = 1.0_wp
[1]	556
	557	!
	558	!-- Initialize near-wall mixing length l_wall only in the vertical direction
	559	!-- for the moment,
	560	!-- multiplication with wall_adjustment_factor near the end of this routine
	561	l_wall(nzb,:,:) = l_grid(1)
	562	DO k = nzb+1, nzt
	563	l_wall(k,:,:) = l_grid(k)
	564	ENDDO
	565	l_wall(nzt+1,:,:) = l_grid(nzt)
	566
	567	ALLOCATE ( vertical_influence(nzb:nzt) )
	568	DO k = 1, nzt
	569	vertical_influence(k) = MIN ( INT( l_grid(k) / &
[1353]	570	( wall_adjustment_factor * dzw(k) ) + 0.5_wp ), nzt - k )
[1]	571	ENDDO
	572
[1968]	573	DO k = 1, nzt
[1353]	574	IF ( l_grid(k) > 1.5_wp * dx * wall_adjustment_factor .OR. &
	575	l_grid(k) > 1.5_wp * dy * wall_adjustment_factor ) THEN
[254]	576	WRITE( message_string, * ) 'grid anisotropy exceeds ', &
	577	'threshold given by only local', &
	578	' &horizontal reduction of near_wall ', &
	579	'mixing length l_wall', &
	580	' &starting from height level k = ', k, '.'
	581	CALL message( 'init_grid', 'PA0202', 0, 1, 0, 6, 0 )
[1]	582	EXIT
	583	ENDIF
	584	ENDDO
	585	vertical_influence(0) = vertical_influence(1)
	586
[1968]	587	DO k = nzb + 1, nzb + vertical_influence(nzb)
	588	l_wall(k,:,:) = zu(k) - zw(nzb)
[1]	589	ENDDO
	590
	591	!
	592	!-- Set outer and inner index arrays for non-flat topography.
	593	!-- Here consistency checks concerning domain size and periodicity are
	594	!-- necessary.
	595	!-- Within this SELECT CASE structure only nzb_local is initialized
	596	!-- individually depending on the chosen topography type, all other index
	597	!-- arrays are initialized further below.
	598	SELECT CASE ( TRIM( topography ) )
	599
	600	CASE ( 'flat' )
	601	!
[555]	602	!-- nzb_local is required for the multigrid solver
	603	nzb_local = 0
[1]	604
	605	CASE ( 'single_building' )
	606	!
	607	!-- Single rectangular building, by default centered in the middle of the
	608	!-- total domain
	609	blx = NINT( building_length_x / dx )
	610	bly = NINT( building_length_y / dy )
[1675]	611	bh = MINLOC( ABS( zw - building_height ), 1 ) - 1
	612	IF ( ABS( zw(bh ) - building_height ) == &
	613	ABS( zw(bh+1) - building_height ) ) bh = bh + 1
[1]	614
[1322]	615	IF ( building_wall_left == 9999999.9_wp ) THEN
[1]	616	building_wall_left = ( nx + 1 - blx ) / 2 * dx
	617	ENDIF
	618	bxl = NINT( building_wall_left / dx )
	619	bxr = bxl + blx
	620
[1322]	621	IF ( building_wall_south == 9999999.9_wp ) THEN
[1]	622	building_wall_south = ( ny + 1 - bly ) / 2 * dy
	623	ENDIF
	624	bys = NINT( building_wall_south / dy )
	625	byn = bys + bly
	626
	627	!
	628	!-- Building size has to meet some requirements
	629	IF ( ( bxl < 1 ) .OR. ( bxr > nx-1 ) .OR. ( bxr < bxl+3 ) .OR. &
	630	( bys < 1 ) .OR. ( byn > ny-1 ) .OR. ( byn < bys+3 ) ) THEN
[274]	631	WRITE( message_string, * ) 'inconsistent building parameters:', &
	632	'& bxl=', bxl, 'bxr=', bxr, 'bys=', bys, &
	633	'byn=', byn, 'nx=', nx, 'ny=', ny
[254]	634	CALL message( 'init_grid', 'PA0203', 1, 2, 0, 6, 0 )
[1]	635	ENDIF
	636
	637	!
[1968]	638	!-- Define the building.
[1]	639	nzb_local = 0
[1968]	640	IF ( bxl <= nxr .AND. bxr >= nxl .AND. &
	641	bys <= nyn .AND. byn >= nys ) &
	642	nzb_local(MAX(nys,bys):MIN(nyn,byn),MAX(nxl,bxl):MIN(nxr,bxr)) = bh
[1]	643
[240]	644	CASE ( 'single_street_canyon' )
	645	!
	646	!-- Single quasi-2D street canyon of infinite length in x or y direction.
	647	!-- The canyon is centered in the other direction by default.
[1322]	648	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[240]	649	!
	650	!-- Street canyon in y direction
	651	cwx = NINT( canyon_width_x / dx )
[1322]	652	IF ( canyon_wall_left == 9999999.9_wp ) THEN
[240]	653	canyon_wall_left = ( nx + 1 - cwx ) / 2 * dx
	654	ENDIF
	655	cxl = NINT( canyon_wall_left / dx )
	656	cxr = cxl + cwx
	657
[1322]	658	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[240]	659	!
	660	!-- Street canyon in x direction
	661	cwy = NINT( canyon_width_y / dy )
[1322]	662	IF ( canyon_wall_south == 9999999.9_wp ) THEN
[240]	663	canyon_wall_south = ( ny + 1 - cwy ) / 2 * dy
	664	ENDIF
	665	cys = NINT( canyon_wall_south / dy )
	666	cyn = cys + cwy
	667
	668	ELSE
[254]	669
	670	message_string = 'no street canyon width given'
	671	CALL message( 'init_grid', 'PA0204', 1, 2, 0, 6, 0 )
	672
[240]	673	ENDIF
	674
[1675]	675	ch = MINLOC( ABS( zw - canyon_height ), 1 ) - 1
	676	IF ( ABS( zw(ch ) - canyon_height ) == &
	677	ABS( zw(ch+1) - canyon_height ) ) ch = ch + 1
	678
[240]	679	dp_level_ind_b = ch
	680	!
	681	!-- Street canyon size has to meet some requirements
[1322]	682	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[1353]	683	IF ( ( cxl < 1 ) .OR. ( cxr > nx-1 ) .OR. ( cwx < 3 ) .OR. &
[240]	684	( ch < 3 ) ) THEN
[1353]	685	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
	686	'&cxl=', cxl, 'cxr=', cxr, &
	687	'cwx=', cwx, &
[254]	688	'ch=', ch, 'nx=', nx, 'ny=', ny
	689	CALL message( 'init_grid', 'PA0205', 1, 2, 0, 6, 0 )
[240]	690	ENDIF
[1322]	691	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[1353]	692	IF ( ( cys < 1 ) .OR. ( cyn > ny-1 ) .OR. ( cwy < 3 ) .OR. &
[240]	693	( ch < 3 ) ) THEN
[1353]	694	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
	695	'&cys=', cys, 'cyn=', cyn, &
	696	'cwy=', cwy, &
[254]	697	'ch=', ch, 'nx=', nx, 'ny=', ny
	698	CALL message( 'init_grid', 'PA0206', 1, 2, 0, 6, 0 )
[240]	699	ENDIF
	700	ENDIF
[1353]	701	IF ( canyon_width_x /= 9999999.9_wp .AND. &
	702	canyon_width_y /= 9999999.9_wp ) THEN
	703	message_string = 'inconsistent canyon parameters:' // &
	704	'&street canyon can only be oriented' // &
[254]	705	'&either in x- or in y-direction'
	706	CALL message( 'init_grid', 'PA0207', 1, 2, 0, 6, 0 )
[240]	707	ENDIF
	708
	709	nzb_local = ch
[1322]	710	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[1968]	711	IF ( cxl <= nxr .AND. cxr >= nxl ) &
	712	nzb_local(:,MAX(nxl,cxl+1):MIN(nxr,cxr-1)) = 0
[1322]	713	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[1968]	714	IF ( cys <= nyn .AND. cyn >= nys ) &
	715	nzb_local(MAX(nys,cys+1):MIN(nyn,cyn-1),:) = 0
[240]	716	ENDIF
	717
[1]	718	CASE ( 'read_from_file' )
[759]	719
[1968]	720	ALLOCATE ( topo_height(nys:nyn,nxl:nxr) )
[818]	721
[759]	722	DO ii = 0, io_blocks-1
	723	IF ( ii == io_group ) THEN
	724
[1]	725	!
[759]	726	!-- Arbitrary irregular topography data in PALM format (exactly
	727	!-- matching the grid size and total domain size)
[1779]	728	OPEN( 90, FILE='TOPOGRAPHY_DATA'//TRIM( coupling_char ), &
	729	STATUS='OLD', FORM='FORMATTED', ERR=10 )
[1968]	730	!
	731	!-- Read topography PE-wise. Rows are read from nyn to nys, columns
	732	!-- are read from nxl to nxr. At first, ny-nyn rows need to be skipped.
	733	skip_n_rows = 0
	734	DO WHILE ( skip_n_rows < ny - nyn )
	735	READ( 90, * )
	736	skip_n_rows = skip_n_rows + 1
[759]	737	ENDDO
[1968]	738	!
	739	!-- Read data from nyn to nys and nxl to nxr. Therefore, skip
	740	!-- column until nxl-1 is reached
	741	DO j = nyn, nys, -1
	742	READ( 90, *, ERR=11, END=11 ) &
	743	( dum, i = 0, nxl-1 ), &
	744	( topo_height(j,i), i = nxl, nxr )
	745	ENDDO
[759]	746
	747	GOTO 12
	748
[1779]	749	10 message_string = 'file TOPOGRAPHY'//TRIM( coupling_char )// &
	750	' does not exist'
[759]	751	CALL message( 'init_grid', 'PA0208', 1, 2, 0, 6, 0 )
	752
[1779]	753	11 message_string = 'errors in file TOPOGRAPHY_DATA'// &
	754	TRIM( coupling_char )
[759]	755	CALL message( 'init_grid', 'PA0209', 1, 2, 0, 6, 0 )
	756
	757	12 CLOSE( 90 )
	758
	759	ENDIF
[1804]	760	#if defined( __parallel )
[759]	761	CALL MPI_BARRIER( comm2d, ierr )
	762	#endif
[559]	763	ENDDO
[759]	764
[1]	765	!
	766	!-- Calculate the index height of the topography
[1968]	767	nzb_local = 0
	768	DO i = nxl, nxr
	769	DO j = nys, nyn
[1675]	770	nzb_local(j,i) = MINLOC( ABS( zw - topo_height(j,i) ), 1 ) - 1
	771	IF ( ABS( zw(nzb_local(j,i) ) - topo_height(j,i) ) == &
	772	ABS( zw(nzb_local(j,i)+1) - topo_height(j,i) ) ) &
	773	nzb_local(j,i) = nzb_local(j,i) + 1
[1]	774	ENDDO
	775	ENDDO
[818]	776
	777	DEALLOCATE ( topo_height )
[1942]	778	!
	779	!-- Filter topography, i.e. fill holes resolved by only one grid point.
	780	!-- Such holes are suspected to lead to velocity blow-ups as continuity
	781	!-- equation on discrete grid cannot be fulfilled in such case.
	782	!-- For now, check only for holes and fill them to the lowest height level
	783	!-- of the directly adjoining grid points along x- and y- direction.
	784	!-- Before checking for holes, set lateral boundary conditions for
	785	!-- topography. After hole-filling, boundary conditions must be set again!
[1968]	786	CALL exchange_horiz_2d_int( nzb_local, nys, nyn, nxl, nxr, nbgp )
	787
	788	IF ( .NOT. bc_ns_cyc ) THEN
	789	IF ( nys == 0 ) nzb_local(-1,:) = nzb_local(0,:)
	790	IF ( nyn == ny ) nzb_local(ny+1,:) = nzb_local(ny,:)
[1942]	791	ENDIF
[1910]	792
[1968]	793	IF ( .NOT. bc_lr_cyc ) THEN
	794	IF ( nxl == 0 ) nzb_local(:,-1) = nzb_local(:,0)
	795	IF ( nxr == nx ) nzb_local(:,nx+1) = nzb_local(:,nx)
[1942]	796	ENDIF
	797
[1968]	798	num_hole_l = 0
	799	DO i = nxl, nxr
	800	DO j = nys, nyn
[1942]	801
	802	num_wall = 0
	803
	804	IF ( nzb_local(j-1,i) > nzb_local(j,i) ) &
	805	num_wall = num_wall + 1
	806	IF ( nzb_local(j+1,i) > nzb_local(j,i) ) &
	807	num_wall = num_wall + 1
	808	IF ( nzb_local(j,i-1) > nzb_local(j,i) ) &
	809	num_wall = num_wall + 1
	810	IF ( nzb_local(j,i+1) > nzb_local(j,i) ) &
	811	num_wall = num_wall + 1
	812
	813	IF ( num_wall == 4 ) THEN
	814	nzb_local(j,i) = MIN( nzb_local(j-1,i), nzb_local(j+1,i), &
	815	nzb_local(j,i-1), nzb_local(j,i+1) )
[1968]	816	num_hole_l = num_hole_l + 1
[1942]	817	ENDIF
	818	ENDDO
	819	ENDDO
[114]	820	!
[1968]	821	!-- Count the total number of holes, required for informative message.
	822	#if defined( __parallel )
	823	CALL MPI_ALLREDUCE( num_hole_l, num_hole, 1, MPI_INTEGER, MPI_SUM, &
	824	comm2d, ierr )
	825	#else
	826	num_hole = num_hole_l
	827	#endif
	828	!
[1942]	829	!-- Create an informative message if any hole was removed.
[1968]	830	IF ( num_hole > 0 ) THEN
[1942]	831	WRITE( message_string, * ) num_hole, 'hole(s) resolved by only '//&
	832	'one grid point were filled'
	833	CALL message( 'init_grid', 'PA0430', 0, 0, 0, 6, 0 )
	834	ENDIF
	835	!
[1968]	836	!-- Exchange ghost-points, as well as add cyclic or Neumann boundary
	837	!-- conditions.
	838	CALL exchange_horiz_2d_int( nzb_local, nys, nyn, nxl, nxr, nbgp )
	839
	840	IF ( .NOT. bc_ns_cyc ) THEN
	841	IF ( nys == 0 ) nzb_local(-1,:) = nzb_local(0,:)
	842	IF ( nyn == ny ) nzb_local(ny+1,:) = nzb_local(ny,:)
[1910]	843	ENDIF
[667]	844
[1968]	845	IF ( .NOT. bc_lr_cyc ) THEN
	846	IF ( nxl == 0 ) nzb_local(:,-1) = nzb_local(:,0)
	847	IF ( nxr == nx ) nzb_local(:,nx+1) = nzb_local(:,nx)
[1910]	848	ENDIF
	849
[1]	850	CASE DEFAULT
	851	!
	852	!-- The DEFAULT case is reached either if the parameter topography
[217]	853	!-- contains a wrong character string or if the user has defined a special
[1]	854	!-- case in the user interface. There, the subroutine user_init_grid
	855	!-- checks which of these two conditions applies.
[1968]	856	CALL user_init_grid( nzb_local )
[1]	857
	858	END SELECT
	859	!
[861]	860	!-- Determine the maximum level of topography. Furthermore it is used for
	861	!-- steering the degradation of order of the applied advection scheme.
[978]	862	!-- In case of non-cyclic lateral boundaries, the order of the advection
[1968]	863	!-- scheme has to be reduced up to nzt (required at the lateral boundaries).
	864	#if defined( __parallel )
	865	CALL MPI_ALLREDUCE( MAXVAL( nzb_local ) + 1, nzb_max, 1, MPI_INTEGER, &
	866	MPI_MAX, comm2d, ierr )
	867	#else
[1677]	868	nzb_max = MAXVAL( nzb_local ) + 1
[1968]	869	#endif
[1353]	870	IF ( inflow_l .OR. outflow_l .OR. inflow_r .OR. outflow_r .OR. &
[1762]	871	inflow_n .OR. outflow_n .OR. inflow_s .OR. outflow_s .OR. &
	872	nest_domain ) &
	873	THEN
	874	nzb_max = nzt
[978]	875	ENDIF
	876
[861]	877	!
[1]	878	!-- Consistency checks and index array initialization are only required for
[217]	879	!-- non-flat topography, also the initialization of topography height arrays
[49]	880	!-- zu_s_inner and zw_w_inner
[1]	881	IF ( TRIM( topography ) /= 'flat' ) THEN
[1968]	882	#if defined( __parallel )
	883	CALL MPI_ALLREDUCE( MAXVAL( nzb_local ), nzb_local_max, 1, MPI_INTEGER, &
	884	MPI_MAX, comm2d, ierr )
[1982]	885	CALL MPI_ALLREDUCE( MINVAL( nzb_local ), nzb_local_min, 1, MPI_INTEGER, &
[1968]	886	MPI_MIN, comm2d, ierr )
	887	#else
	888	nzb_local_max = MAXVAL( nzb_local )
	889	nzb_local_min = MINVAL( nzb_local )
	890	#endif
[1982]	891
[1]	892	!
	893	!-- Consistency checks
[1968]	894	IF ( nzb_local_min < 0 .OR. nzb_local_max > nz + 1 ) THEN
[1353]	895	WRITE( message_string, * ) 'nzb_local values are outside the', &
	896	'model domain', &
[1968]	897	'&MINVAL( nzb_local ) = ', nzb_local_min, &
	898	'&MAXVAL( nzb_local ) = ', nzb_local_max
[254]	899	CALL message( 'init_grid', 'PA0210', 1, 2, 0, 6, 0 )
[1]	900	ENDIF
	901
[217]	902	IF ( topography_grid_convention == 'cell_edge' ) THEN
[134]	903	!
[217]	904	!-- The array nzb_local as defined using the 'cell_edge' convention
	905	!-- describes the actual total size of topography which is defined at the
	906	!-- cell edges where u=0 on the topography walls in x-direction and v=0
	907	!-- on the topography walls in y-direction. However, PALM uses individual
	908	!-- arrays nzb_u\|v\|w\|s_inner\|outer that are based on nzb_s_inner.
	909	!-- Therefore, the extent of topography in nzb_local is now reduced by
	910	!-- 1dx at the E topography walls and by 1dy at the N topography walls
[1968]	911	!-- to form the basis for nzb_s_inner.
	912	!-- Note, the reverse memory access (i-j instead of j-i) is absolutely
	913	!-- required at this point.
	914	DO j = nys+1, nyn+1
	915	DO i = nxl-1, nxr
[217]	916	nzb_local(j,i) = MIN( nzb_local(j,i), nzb_local(j,i+1) )
	917	ENDDO
[134]	918	ENDDO
[1968]	919	!
	920	!-- Exchange ghost points
	921	CALL exchange_horiz_2d_int( nzb_local, nys, nyn, nxl, nxr, nbgp )
	922
	923	DO i = nxl, nxr+1
	924	DO j = nys-1, nyn
[217]	925	nzb_local(j,i) = MIN( nzb_local(j,i), nzb_local(j+1,i) )
	926	ENDDO
[134]	927	ENDDO
[1968]	928	!
	929	!-- Exchange ghost points
	930	CALL exchange_horiz_2d_int( nzb_local, nys, nyn, nxl, nxr, nbgp )
[217]	931	ENDIF
[1]	932	!
	933	!-- Initialize index arrays nzb_s_inner and nzb_w_inner
[1968]	934	nzb_s_inner = nzb_local
	935	nzb_w_inner = nzb_local
[1]	936
	937	!
	938	!-- Initialize remaining index arrays:
	939	!-- first pre-initialize them with nzb_s_inner...
	940	nzb_u_inner = nzb_s_inner
	941	nzb_u_outer = nzb_s_inner
	942	nzb_v_inner = nzb_s_inner
	943	nzb_v_outer = nzb_s_inner
	944	nzb_w_outer = nzb_s_inner
	945	nzb_s_outer = nzb_s_inner
	946
	947	!
	948	!-- ...then extend pre-initialized arrays in their according directions
	949	!-- based on nzb_local using nzb_tmp as a temporary global index array
	950
	951	!
	952	!-- nzb_s_outer:
	953	!-- extend nzb_local east-/westwards first, then north-/southwards
[1968]	954	nzb_tmp = nzb_local
	955	DO j = nys, nyn
	956	DO i = nxl, nxr
[1353]	957	nzb_tmp(j,i) = MAX( nzb_local(j,i-1), nzb_local(j,i), &
[1]	958	nzb_local(j,i+1) )
	959	ENDDO
	960	ENDDO
[1968]	961
	962	CALL exchange_horiz_2d_int( nzb_tmp, nys, nyn, nxl, nxr, nbgp )
	963
[1]	964	DO i = nxl, nxr
	965	DO j = nys, nyn
[1353]	966	nzb_s_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i), &
[1]	967	nzb_tmp(j+1,i) )
	968	ENDDO
	969	!
	970	!-- non-cyclic boundary conditions (overwritten by call of
	971	!-- exchange_horiz_2d_int below in case of cyclic boundary conditions)
	972	IF ( nys == 0 ) THEN
	973	j = -1
	974	nzb_s_outer(j,i) = MAX( nzb_tmp(j+1,i), nzb_tmp(j,i) )
	975	ENDIF
[1743]	976	IF ( nyn == ny ) THEN
[1]	977	j = ny + 1
	978	nzb_s_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i) )
	979	ENDIF
	980	ENDDO
	981	!
	982	!-- nzb_w_outer:
	983	!-- identical to nzb_s_outer
	984	nzb_w_outer = nzb_s_outer
	985
	986	!
	987	!-- nzb_u_inner:
	988	!-- extend nzb_local rightwards only
[1968]	989	nzb_tmp = nzb_local
	990	DO j = nys, nyn
	991	DO i = nxl, nxr
[1]	992	nzb_tmp(j,i) = MAX( nzb_local(j,i-1), nzb_local(j,i) )
	993	ENDDO
	994	ENDDO
[1968]	995
	996	CALL exchange_horiz_2d_int( nzb_tmp, nys, nyn, nxl, nxr, nbgp )
	997
	998	nzb_u_inner = nzb_tmp
[1]	999	!
	1000	!-- nzb_u_outer:
	1001	!-- extend current nzb_tmp (nzb_u_inner) north-/southwards
	1002	DO i = nxl, nxr
	1003	DO j = nys, nyn
[1353]	1004	nzb_u_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i), &
[1]	1005	nzb_tmp(j+1,i) )
	1006	ENDDO
	1007	!
	1008	!-- non-cyclic boundary conditions (overwritten by call of
	1009	!-- exchange_horiz_2d_int below in case of cyclic boundary conditions)
	1010	IF ( nys == 0 ) THEN
	1011	j = -1
	1012	nzb_u_outer(j,i) = MAX( nzb_tmp(j+1,i), nzb_tmp(j,i) )
	1013	ENDIF
[1743]	1014	IF ( nyn == ny ) THEN
[1]	1015	j = ny + 1
	1016	nzb_u_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i) )
	1017	ENDIF
	1018	ENDDO
	1019
	1020	!
	1021	!-- nzb_v_inner:
	1022	!-- extend nzb_local northwards only
[1968]	1023	nzb_tmp = nzb_local
	1024	DO i = nxl, nxr
	1025	DO j = nys, nyn
[1]	1026	nzb_tmp(j,i) = MAX( nzb_local(j-1,i), nzb_local(j,i) )
	1027	ENDDO
	1028	ENDDO
[1968]	1029
	1030	CALL exchange_horiz_2d_int( nzb_tmp, nys, nyn, nxl, nxr, nbgp )
	1031	nzb_v_inner = nzb_tmp
[1]	1032
	1033	!
	1034	!-- nzb_v_outer:
	1035	!-- extend current nzb_tmp (nzb_v_inner) right-/leftwards
	1036	DO j = nys, nyn
	1037	DO i = nxl, nxr
[1353]	1038	nzb_v_outer(j,i) = MAX( nzb_tmp(j,i-1), nzb_tmp(j,i), &
[1]	1039	nzb_tmp(j,i+1) )
	1040	ENDDO
	1041	!
	1042	!-- non-cyclic boundary conditions (overwritten by call of
	1043	!-- exchange_horiz_2d_int below in case of cyclic boundary conditions)
	1044	IF ( nxl == 0 ) THEN
	1045	i = -1
	1046	nzb_v_outer(j,i) = MAX( nzb_tmp(j,i+1), nzb_tmp(j,i) )
	1047	ENDIF
	1048	IF ( nxr == nx ) THEN
	1049	i = nx + 1
	1050	nzb_v_outer(j,i) = MAX( nzb_tmp(j,i-1), nzb_tmp(j,i) )
	1051	ENDIF
	1052	ENDDO
[1804]	1053
[1]	1054	!
	1055	!-- Exchange of lateral boundary values (parallel computers) and cyclic
	1056	!-- boundary conditions, if applicable.
	1057	!-- Since nzb_s_inner and nzb_w_inner are derived directly from nzb_local
	1058	!-- they do not require exchange and are not included here.
[1968]	1059	CALL exchange_horiz_2d_int( nzb_u_inner, nys, nyn, nxl, nxr, nbgp )
	1060	CALL exchange_horiz_2d_int( nzb_u_outer, nys, nyn, nxl, nxr, nbgp )
	1061	CALL exchange_horiz_2d_int( nzb_v_inner, nys, nyn, nxl, nxr, nbgp )
	1062	CALL exchange_horiz_2d_int( nzb_v_outer, nys, nyn, nxl, nxr, nbgp )
	1063	CALL exchange_horiz_2d_int( nzb_w_outer, nys, nyn, nxl, nxr, nbgp )
	1064	CALL exchange_horiz_2d_int( nzb_s_outer, nys, nyn, nxl, nxr, nbgp )
[1]	1065
[49]	1066	!
	1067	!-- Allocate and set the arrays containing the topography height
[1968]	1068	ALLOCATE( zu_s_inner(0:nx+1,0:ny+1), zw_w_inner(0:nx+1,0:ny+1), &
	1069	zu_s_inner_l(0:nx+1,0:ny+1), zw_w_inner_l(0:nx+1,0:ny+1) )
	1070
	1071	zu_s_inner = 0.0_wp
	1072	zw_w_inner = 0.0_wp
	1073	zu_s_inner_l = 0.0_wp
	1074	zw_w_inner_l = 0.0_wp
	1075
	1076	DO i = nxl, nxr
	1077	DO j = nys, nyn
	1078	zu_s_inner_l(i,j) = zu(nzb_local(j,i))
	1079	zw_w_inner_l(i,j) = zw(nzb_local(j,i))
	1080	ENDDO
	1081	ENDDO
	1082
	1083	#if defined( __parallel )
	1084	CALL MPI_REDUCE( zu_s_inner_l, zu_s_inner, (nx+2)*(ny+2), &
	1085	MPI_REAL, MPI_SUM, 0, comm2d, ierr )
	1086	CALL MPI_REDUCE( zw_w_inner_l, zw_w_inner, (nx+2)*(ny+2), &
	1087	MPI_REAL, MPI_SUM, 0, comm2d, ierr )
	1088	#else
	1089	zu_s_inner = zu_s_inner_l
	1090	zw_w_inner = zw_w_inner_l
	1091	#endif
[49]	1092
[1968]	1093	DEALLOCATE( zu_s_inner_l, zw_w_inner_l )
	1094	IF ( myid /= 0 ) DEALLOCATE( zu_s_inner, zw_w_inner )
[1221]	1095	!
[1968]	1096	!-- Set south and left ghost points, required for netcdf output
	1097	IF ( myid == 0 ) THEN
	1098	IF( bc_lr_cyc ) THEN
	1099	zu_s_inner(nx+1,:) = zu_s_inner(0,:)
	1100	zw_w_inner(nx+1,:) = zw_w_inner(0,:)
	1101	ELSE
	1102	zu_s_inner(nx+1,:) = zu_s_inner(nx,:)
	1103	zw_w_inner(nx+1,:) = zw_w_inner(nx,:)
	1104	ENDIF
	1105	IF( bc_ns_cyc ) THEN
	1106	zu_s_inner(:,ny+1) = zu_s_inner(:,0)
	1107	zw_w_inner(:,ny+1) = zw_w_inner(:,0)
	1108	ELSE
	1109	zu_s_inner(:,ny+1) = zu_s_inner(:,ny)
	1110	zw_w_inner(:,ny+1) = zw_w_inner(:,ny)
	1111	ENDIF
	1112	ENDIF
	1113	!
[1221]	1114	!-- Set flag arrays to be used for masking of grid points
	1115	DO i = nxlg, nxrg
	1116	DO j = nysg, nyng
	1117	DO k = nzb, nzt+1
[1353]	1118	IF ( k <= nzb_s_inner(j,i) ) rflags_s_inner(k,j,i) = 0.0_wp
	1119	IF ( k <= nzb_s_inner(j,i) ) rflags_invers(j,i,k) = 0.0_wp
[1221]	1120	ENDDO
	1121	ENDDO
	1122	ENDDO
[1804]	1123
[1]	1124	ENDIF
[1968]	1125	!
	1126	!-- Deallocate temporary array, as it might be reused for different
	1127	!-- grid-levels further below.
	1128	DEALLOCATE( nzb_tmp )
[1]	1129
	1130	!
	1131	!-- Set the individual index arrays which define the k index from which on
	1132	!-- the usual finite difference form (which does not use surface fluxes) is
	1133	!-- applied
[1691]	1134	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[1]	1135	nzb_diff_u = nzb_u_inner + 2
	1136	nzb_diff_v = nzb_v_inner + 2
	1137	nzb_diff_s_inner = nzb_s_inner + 2
	1138	nzb_diff_s_outer = nzb_s_outer + 2
	1139	ELSE
	1140	nzb_diff_u = nzb_u_inner + 1
	1141	nzb_diff_v = nzb_v_inner + 1
	1142	nzb_diff_s_inner = nzb_s_inner + 1
	1143	nzb_diff_s_outer = nzb_s_outer + 1
	1144	ENDIF
	1145
	1146	!
	1147	!-- Calculation of wall switches and factors required by diffusion_u/v.f90 and
	1148	!-- for limitation of near-wall mixing length l_wall further below
	1149	corner_nl = 0
	1150	corner_nr = 0
	1151	corner_sl = 0
	1152	corner_sr = 0
	1153	wall_l = 0
	1154	wall_n = 0
	1155	wall_r = 0
	1156	wall_s = 0
	1157
	1158	DO i = nxl, nxr
	1159	DO j = nys, nyn
	1160	!
	1161	!-- u-component
	1162	IF ( nzb_u_outer(j,i) > nzb_u_outer(j+1,i) ) THEN
[1353]	1163	wall_u(j,i) = 1.0_wp ! north wall (location of adjacent fluid)
	1164	fym(j,i) = 0.0_wp
	1165	fyp(j,i) = 1.0_wp
[1]	1166	ELSEIF ( nzb_u_outer(j,i) > nzb_u_outer(j-1,i) ) THEN
[1353]	1167	wall_u(j,i) = 1.0_wp ! south wall (location of adjacent fluid)
	1168	fym(j,i) = 1.0_wp
	1169	fyp(j,i) = 0.0_wp
[1]	1170	ENDIF
	1171	!
	1172	!-- v-component
	1173	IF ( nzb_v_outer(j,i) > nzb_v_outer(j,i+1) ) THEN
[1353]	1174	wall_v(j,i) = 1.0_wp ! rigth wall (location of adjacent fluid)
	1175	fxm(j,i) = 0.0_wp
	1176	fxp(j,i) = 1.0_wp
[1]	1177	ELSEIF ( nzb_v_outer(j,i) > nzb_v_outer(j,i-1) ) THEN
[1353]	1178	wall_v(j,i) = 1.0_wp ! left wall (location of adjacent fluid)
	1179	fxm(j,i) = 1.0_wp
	1180	fxp(j,i) = 0.0_wp
[1]	1181	ENDIF
	1182	!
	1183	!-- w-component, also used for scalars, separate arrays for shear
	1184	!-- production of tke
	1185	IF ( nzb_w_outer(j,i) > nzb_w_outer(j+1,i) ) THEN
[1353]	1186	wall_e_y(j,i) = 1.0_wp ! north wall (location of adjacent fluid)
	1187	wall_w_y(j,i) = 1.0_wp
	1188	fwym(j,i) = 0.0_wp
	1189	fwyp(j,i) = 1.0_wp
[1]	1190	ELSEIF ( nzb_w_outer(j,i) > nzb_w_outer(j-1,i) ) THEN
[1353]	1191	wall_e_y(j,i) = -1.0_wp ! south wall (location of adjacent fluid)
	1192	wall_w_y(j,i) = 1.0_wp
	1193	fwym(j,i) = 1.0_wp
	1194	fwyp(j,i) = 0.0_wp
[1]	1195	ENDIF
	1196	IF ( nzb_w_outer(j,i) > nzb_w_outer(j,i+1) ) THEN
[1353]	1197	wall_e_x(j,i) = 1.0_wp ! right wall (location of adjacent fluid)
	1198	wall_w_x(j,i) = 1.0_wp
	1199	fwxm(j,i) = 0.0_wp
	1200	fwxp(j,i) = 1.0_wp
[1]	1201	ELSEIF ( nzb_w_outer(j,i) > nzb_w_outer(j,i-1) ) THEN
[1353]	1202	wall_e_x(j,i) = -1.0_wp ! left wall (location of adjacent fluid)
	1203	wall_w_x(j,i) = 1.0_wp
	1204	fwxm(j,i) = 1.0_wp
	1205	fwxp(j,i) = 0.0_wp
[1]	1206	ENDIF
	1207	!
	1208	!-- Wall and corner locations inside buildings for limitation of
	1209	!-- near-wall mixing length l_wall
	1210	IF ( nzb_s_inner(j,i) > nzb_s_inner(j+1,i) ) THEN
	1211
	1212	wall_n(j,i) = nzb_s_inner(j+1,i) + 1 ! North wall
	1213
	1214	IF ( nzb_s_inner(j,i) > nzb_s_inner(j,i-1) ) THEN
	1215	corner_nl(j,i) = MAX( nzb_s_inner(j+1,i), & ! Northleft corner
	1216	nzb_s_inner(j,i-1) ) + 1
	1217	ENDIF
	1218
	1219	IF ( nzb_s_inner(j,i) > nzb_s_inner(j,i+1) ) THEN
	1220	corner_nr(j,i) = MAX( nzb_s_inner(j+1,i), & ! Northright corner
	1221	nzb_s_inner(j,i+1) ) + 1
	1222	ENDIF
	1223
	1224	ENDIF
	1225
	1226	IF ( nzb_s_inner(j,i) > nzb_s_inner(j-1,i) ) THEN
	1227
	1228	wall_s(j,i) = nzb_s_inner(j-1,i) + 1 ! South wall
	1229	IF ( nzb_s_inner(j,i) > nzb_s_inner(j,i-1) ) THEN
	1230	corner_sl(j,i) = MAX( nzb_s_inner(j-1,i), & ! Southleft corner
	1231	nzb_s_inner(j,i-1) ) + 1
	1232	ENDIF
	1233
	1234	IF ( nzb_s_inner(j,i) > nzb_s_inner(j,i+1) ) THEN
	1235	corner_sr(j,i) = MAX( nzb_s_inner(j-1,i), & ! Southright corner
	1236	nzb_s_inner(j,i+1) ) + 1
	1237	ENDIF
	1238
	1239	ENDIF
	1240
	1241	IF ( nzb_s_inner(j,i) > nzb_s_inner(j,i-1) ) THEN
	1242	wall_l(j,i) = nzb_s_inner(j,i-1) + 1 ! Left wall
	1243	ENDIF
	1244
	1245	IF ( nzb_s_inner(j,i) > nzb_s_inner(j,i+1) ) THEN
	1246	wall_r(j,i) = nzb_s_inner(j,i+1) + 1 ! Right wall
	1247	ENDIF
	1248
	1249	ENDDO
	1250	ENDDO
	1251	!
[1931]	1252	!-- Calculate wall flag arrays for the multigrid method.
	1253	!-- Please note, wall flags are only applied in the not cache-optimized
	1254	!-- version.
	1255	IF ( psolver == 'multigrid_noopt' ) THEN
[1968]	1256
[114]	1257	!
[1968]	1258	!-- Gridpoint increment of the current level.
[114]	1259	inc = 1
	1260	DO l = maximum_grid_level, 1 , -1
[1968]	1261	!
	1262	!-- Set grid_level as it is required for exchange_horiz_2d_int
	1263	grid_level = l
[114]	1264
	1265	nxl_l = nxl_mg(l)
	1266	nxr_l = nxr_mg(l)
	1267	nys_l = nys_mg(l)
	1268	nyn_l = nyn_mg(l)
	1269	nzt_l = nzt_mg(l)
	1270	!
	1271	!-- Assign the flag level to be calculated
	1272	SELECT CASE ( l )
	1273	CASE ( 1 )
	1274	flags => wall_flags_1
	1275	CASE ( 2 )
	1276	flags => wall_flags_2
	1277	CASE ( 3 )
	1278	flags => wall_flags_3
	1279	CASE ( 4 )
	1280	flags => wall_flags_4
	1281	CASE ( 5 )
	1282	flags => wall_flags_5
	1283	CASE ( 6 )
	1284	flags => wall_flags_6
	1285	CASE ( 7 )
	1286	flags => wall_flags_7
	1287	CASE ( 8 )
	1288	flags => wall_flags_8
	1289	CASE ( 9 )
	1290	flags => wall_flags_9
	1291	CASE ( 10 )
	1292	flags => wall_flags_10
	1293	END SELECT
	1294
	1295	!
	1296	!-- Depending on the grid level, set the respective bits in case of
	1297	!-- neighbouring walls
	1298	!-- Bit 0: wall to the bottom
	1299	!-- Bit 1: wall to the top (not realized in remaining PALM code so far)
	1300	!-- Bit 2: wall to the south
	1301	!-- Bit 3: wall to the north
	1302	!-- Bit 4: wall to the left
	1303	!-- Bit 5: wall to the right
[116]	1304	!-- Bit 6: inside building
[114]	1305
	1306	flags = 0
	1307
[927]	1308	!
	1309	!-- In case of masking method, flags are not set and multigrid method
	1310	!-- works like FFT-solver
[1931]	1311	IF ( .NOT. masking_method ) THEN
[927]	1312
[1968]	1313	!
	1314	!-- Allocate temporary array for topography heights on coarser grid
	1315	!-- level. Please note, 2 ghoist points are required, in order to
	1316	!-- calculate flags() on the interior ghost point.
	1317	ALLOCATE( nzb_tmp(nys_l-2:nyn_l+2,nxl_l-2:nxr_l+2) )
	1318	nzb_tmp = 0
	1319
	1320	DO i = nxl_l, nxr_l
	1321	DO j = nys_l, nyn_l
	1322	nzb_tmp(j,i) = nzb_local(jinc,iinc)
	1323	ENDDO
	1324	ENDDO
	1325	!
	1326	!-- Exchange ghost points on respective multigrid level. 2 ghost points
	1327	!-- are required, in order to calculate flags on
	1328	!-- nys_l-1 / nyn_l+1 / nxl_l-1 / nxr_l+1. The alternative would be to
	1329	!-- exchange 3D-INTEGER array flags on the respective multigrid level.
	1330	CALL exchange_horiz_2d_int( nzb_tmp, nys_l, nyn_l, nxl_l, nxr_l, 2 )
	1331	!
	1332	!-- Set non-cyclic boundary conditions on respective multigrid level
	1333	IF ( .NOT. bc_ns_cyc ) THEN
	1334	IF ( nys == 0 ) THEN
	1335	nzb_tmp(-2,:) = nzb_tmp(0,:)
	1336	nzb_tmp(-1,:) = nzb_tmp(0,:)
	1337	ENDIF
	1338	IF ( nyn == ny ) THEN
	1339	nzb_tmp(ny+2,:) = nzb_tmp(ny,:)
	1340	nzb_tmp(ny+1,:) = nzb_tmp(ny,:)
	1341	ENDIF
	1342	ENDIF
	1343	IF ( .NOT. bc_lr_cyc ) THEN
	1344	IF ( nxl == 0 ) THEN
	1345	nzb_tmp(:,-2) = nzb_tmp(:,0)
	1346	nzb_tmp(:,-1) = nzb_tmp(:,0)
	1347	ENDIF
	1348	IF ( nxr == nx ) THEN
	1349	nzb_tmp(:,nx+1) = nzb_tmp(:,nx)
	1350	nzb_tmp(:,nx+2) = nzb_tmp(:,nx)
	1351	ENDIF
	1352	ENDIF
	1353
[927]	1354	DO i = nxl_l-1, nxr_l+1
	1355	DO j = nys_l-1, nyn_l+1
[1968]	1356	DO k = nzb, nzt_l+1
[114]	1357	!
[927]	1358	!-- Inside/outside building (inside building does not need
	1359	!-- further tests for walls)
[1968]	1360	IF ( k*inc <= nzb_tmp(j,i) ) THEN
[114]	1361
[927]	1362	flags(k,j,i) = IBSET( flags(k,j,i), 6 )
[114]	1363
[927]	1364	ELSE
[114]	1365	!
[927]	1366	!-- Bottom wall
[1968]	1367	IF ( (k-1)*inc <= nzb_tmp(j,i) ) THEN
[927]	1368	flags(k,j,i) = IBSET( flags(k,j,i), 0 )
	1369	ENDIF
[114]	1370	!
[927]	1371	!-- South wall
[1968]	1372	IF ( k*inc <= nzb_tmp(j-1,i) ) THEN
[927]	1373	flags(k,j,i) = IBSET( flags(k,j,i), 2 )
	1374	ENDIF
[114]	1375	!
[927]	1376	!-- North wall
[1968]	1377	IF ( k*inc <= nzb_tmp(j+1,i) ) THEN
[927]	1378	flags(k,j,i) = IBSET( flags(k,j,i), 3 )
	1379	ENDIF
[114]	1380	!
[927]	1381	!-- Left wall
[1968]	1382	IF ( k*inc <= nzb_tmp(j,i-1) ) THEN
[927]	1383	flags(k,j,i) = IBSET( flags(k,j,i), 4 )
	1384	ENDIF
[114]	1385	!
[927]	1386	!-- Right wall
[1968]	1387	IF ( k*inc <= nzb_tmp(j,i+1) ) THEN
[927]	1388	flags(k,j,i) = IBSET( flags(k,j,i), 5 )
	1389	ENDIF
	1390
[114]	1391	ENDIF
	1392
[927]	1393	ENDDO
[114]	1394	ENDDO
	1395	ENDDO
	1396
[1968]	1397	DEALLOCATE( nzb_tmp )
	1398
[927]	1399	ENDIF
	1400
[114]	1401	inc = inc * 2
	1402
	1403	ENDDO
[1968]	1404	!
	1405	!-- Reset grid_level to "normal" grid
	1406	grid_level = 0
	1407
[114]	1408	ENDIF
[861]	1409	!
[1942]	1410	!-- Allocate flags needed for masking walls. Even though these flags are only
	1411	!-- required in the ws-scheme, the arrays need to be allocated as they are
	1412	!-- used in OpenACC directives.
[1677]	1413	ALLOCATE( wall_flags_0(nzb:nzt+1,nysg:nyng,nxlg:nxrg), &
	1414	wall_flags_00(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
[1221]	1415	wall_flags_0 = 0
	1416	wall_flags_00 = 0
[114]	1417	!
[1942]	1418	!-- Init flags for ws-scheme to degrade order near walls
	1419	IF ( momentum_advec == 'ws-scheme' .OR. scalar_advec == 'ws-scheme' .OR.&
	1420	scalar_advec == 'ws-scheme-mono' ) THEN
	1421	CALL ws_init_flags
[861]	1422	ENDIF
	1423
	1424	!
[1]	1425	!-- In case of topography: limit near-wall mixing length l_wall further:
	1426	!-- Go through all points of the subdomain one by one and look for the closest
	1427	!-- surface
	1428	IF ( TRIM(topography) /= 'flat' ) THEN
	1429	DO i = nxl, nxr
	1430	DO j = nys, nyn
	1431
	1432	nzb_si = nzb_s_inner(j,i)
	1433	vi = vertical_influence(nzb_si)
	1434
	1435	IF ( wall_n(j,i) > 0 ) THEN
	1436	!
	1437	!-- North wall (y distance)
	1438	DO k = wall_n(j,i), nzb_si
[1353]	1439	l_wall(k,j+1,i) = MIN( l_wall(k,j+1,i), 0.5_wp * dy )
[1]	1440	ENDDO
	1441	!
	1442	!-- Above North wall (yz distance)
	1443	DO k = nzb_si + 1, nzb_si + vi
[1353]	1444	l_wall(k,j+1,i) = MIN( l_wall(k,j+1,i), &
	1445	SQRT( 0.25_wp * dy**2 + &
[1]	1446	( zu(k) - zw(nzb_si) )**2 ) )
	1447	ENDDO
	1448	!
	1449	!-- Northleft corner (xy distance)
	1450	IF ( corner_nl(j,i) > 0 ) THEN
	1451	DO k = corner_nl(j,i), nzb_si
	1452	l_wall(k,j+1,i-1) = MIN( l_wall(k,j+1,i-1), &
[1353]	1453	0.5_wp * SQRT( dx2 + dy2 ) )
[1]	1454	ENDDO
	1455	!
	1456	!-- Above Northleft corner (xyz distance)
	1457	DO k = nzb_si + 1, nzb_si + vi
[1353]	1458	l_wall(k,j+1,i-1) = MIN( l_wall(k,j+1,i-1), &
	1459	SQRT( 0.25_wp * (dx2 + dy2) + &
	1460	( zu(k) - zw(nzb_si) )**2 ) )
[1]	1461	ENDDO
	1462	ENDIF
	1463	!
	1464	!-- Northright corner (xy distance)
	1465	IF ( corner_nr(j,i) > 0 ) THEN
	1466	DO k = corner_nr(j,i), nzb_si
[1353]	1467	l_wall(k,j+1,i+1) = MIN( l_wall(k,j+1,i+1), &
	1468	0.5_wp * SQRT( dx2 + dy2 ) )
[1]	1469	ENDDO
	1470	!
	1471	!-- Above northright corner (xyz distance)
	1472	DO k = nzb_si + 1, nzb_si + vi
[1353]	1473	l_wall(k,j+1,i+1) = MIN( l_wall(k,j+1,i+1), &
	1474	SQRT( 0.25_wp * (dx2 + dy2) + &
	1475	( zu(k) - zw(nzb_si) )**2 ) )
[1]	1476	ENDDO
	1477	ENDIF
	1478	ENDIF
	1479
	1480	IF ( wall_s(j,i) > 0 ) THEN
	1481	!
	1482	!-- South wall (y distance)
	1483	DO k = wall_s(j,i), nzb_si
[1353]	1484	l_wall(k,j-1,i) = MIN( l_wall(k,j-1,i), 0.5_wp * dy )
[1]	1485	ENDDO
	1486	!
	1487	!-- Above south wall (yz distance)
[1353]	1488	DO k = nzb_si + 1, nzb_si + vi
	1489	l_wall(k,j-1,i) = MIN( l_wall(k,j-1,i), &
	1490	SQRT( 0.25_wp * dy**2 + &
[1]	1491	( zu(k) - zw(nzb_si) )**2 ) )
	1492	ENDDO
	1493	!
	1494	!-- Southleft corner (xy distance)
	1495	IF ( corner_sl(j,i) > 0 ) THEN
	1496	DO k = corner_sl(j,i), nzb_si
[1353]	1497	l_wall(k,j-1,i-1) = MIN( l_wall(k,j-1,i-1), &
	1498	0.5_wp * SQRT( dx2 + dy2 ) )
[1]	1499	ENDDO
	1500	!
	1501	!-- Above southleft corner (xyz distance)
	1502	DO k = nzb_si + 1, nzb_si + vi
[1353]	1503	l_wall(k,j-1,i-1) = MIN( l_wall(k,j-1,i-1), &
	1504	SQRT( 0.25_wp * (dx2 + dy2) + &
	1505	( zu(k) - zw(nzb_si) )**2 ) )
[1]	1506	ENDDO
	1507	ENDIF
	1508	!
	1509	!-- Southright corner (xy distance)
	1510	IF ( corner_sr(j,i) > 0 ) THEN
	1511	DO k = corner_sr(j,i), nzb_si
[1353]	1512	l_wall(k,j-1,i+1) = MIN( l_wall(k,j-1,i+1), &
	1513	0.5_wp * SQRT( dx2 + dy2 ) )
[1]	1514	ENDDO
	1515	!
	1516	!-- Above southright corner (xyz distance)
	1517	DO k = nzb_si + 1, nzb_si + vi
[1353]	1518	l_wall(k,j-1,i+1) = MIN( l_wall(k,j-1,i+1), &
	1519	SQRT( 0.25_wp * (dx2 + dy2) + &
	1520	( zu(k) - zw(nzb_si) )**2 ) )
[1]	1521	ENDDO
	1522	ENDIF
	1523
	1524	ENDIF
	1525
	1526	IF ( wall_l(j,i) > 0 ) THEN
	1527	!
	1528	!-- Left wall (x distance)
	1529	DO k = wall_l(j,i), nzb_si
[1353]	1530	l_wall(k,j,i-1) = MIN( l_wall(k,j,i-1), 0.5_wp * dx )
[1]	1531	ENDDO
	1532	!
	1533	!-- Above left wall (xz distance)
	1534	DO k = nzb_si + 1, nzb_si + vi
[1353]	1535	l_wall(k,j,i-1) = MIN( l_wall(k,j,i-1), &
	1536	SQRT( 0.25_wp * dx**2 + &
	1537	( zu(k) - zw(nzb_si) )**2 ) )
[1]	1538	ENDDO
	1539	ENDIF
	1540
	1541	IF ( wall_r(j,i) > 0 ) THEN
	1542	!
	1543	!-- Right wall (x distance)
	1544	DO k = wall_r(j,i), nzb_si
[1353]	1545	l_wall(k,j,i+1) = MIN( l_wall(k,j,i+1), 0.5_wp * dx )
[1]	1546	ENDDO
	1547	!
	1548	!-- Above right wall (xz distance)
	1549	DO k = nzb_si + 1, nzb_si + vi
[1353]	1550	l_wall(k,j,i+1) = MIN( l_wall(k,j,i+1), &
	1551	SQRT( 0.25_wp * dx**2 + &
[1]	1552	( zu(k) - zw(nzb_si) )**2 ) )
	1553	ENDDO
	1554
	1555	ENDIF
	1556
	1557	ENDDO
	1558	ENDDO
	1559
	1560	ENDIF
	1561
	1562	!
	1563	!-- Multiplication with wall_adjustment_factor
	1564	l_wall = wall_adjustment_factor * l_wall
	1565
	1566	!
[709]	1567	!-- Set lateral boundary conditions for l_wall
[667]	1568	CALL exchange_horiz( l_wall, nbgp )
	1569
[1]	1570	DEALLOCATE( corner_nl, corner_nr, corner_sl, corner_sr, nzb_local, &
[1968]	1571	vertical_influence, wall_l, wall_n, wall_r, wall_s )
[1]	1572
	1573
	1574	END SUBROUTINE init_grid

Note: See TracBrowser for help on using the repository browser.

Download in other formats:

| Impressum | ©Leibniz Universität Hannover |