Home

Context Navigation

source: palm/trunk/SOURCE/init_grid.f90 @ 4408

Last change on this file since 4408 was 4386, checked in by Giersch, 5 years ago
Allocation statements, comments, naming of variables revised and _wp added to real type values
Property svn:keywords set to `Id`
File size: 125.4 KB

Rev	Line
[1682]	1	!> @file init_grid.f90
[2000]	2	!------------------------------------------------------------------------------!
[2696]	3	! This file is part of the PALM model system.
[1036]	4	!
[2000]	5	! PALM is free software: you can redistribute it and/or modify it under the
	6	! terms of the GNU General Public License as published by the Free Software
	7	! Foundation, either version 3 of the License, or (at your option) any later
	8	! version.
[1036]	9	!
	10	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
	11	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
	12	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
	13	!
	14	! You should have received a copy of the GNU General Public License along with
	15	! PALM. If not, see <http://www.gnu.org/licenses/>.
	16	!
[4360]	17	! Copyright 1997-2020 Leibniz Universitaet Hannover
[2000]	18	!------------------------------------------------------------------------------!
[1036]	19	!
[254]	20	! Current revisions:
[1]	21	! -----------------
[2233]	22	!
[4110]	23	!
[2233]	24	! Former revisions:
	25	! -----------------
	26	! $Id: init_grid.f90 4386 2020-01-27 15:07:30Z gronemeier $
[4386]	27	! Allocation statements, comments, naming of variables revised and _wp added to
	28	! real type values
	29	!
	30	! 4360 2020-01-07 11:25:50Z suehring
[4356]	31	! Revise error messages for generic tunnel setup.
	32	!
	33	! 4346 2019-12-18 11:55:56Z motisi
[4346]	34	! Introduction of wall_flags_total_0, which currently sets bits based on static
	35	! topography information used in wall_flags_static_0
	36	!
	37	! 4340 2019-12-16 08:17:03Z Giersch
[4340]	38	! Topography closed channel flow with symmetric boundaries implemented
	39	!
	40	! 4329 2019-12-10 15:46:36Z motisi
[4329]	41	! Renamed wall_flags_0 to wall_flags_static_0
	42	!
	43	! 4328 2019-12-09 18:53:04Z suehring
[4328]	44	! Minor change in nzb_max computation. Commentation added.
	45	!
	46	! 4314 2019-11-29 10:29:20Z suehring
[4314]	47	! Set additional topography flag 4 to mark topography grid points emerged
	48	! from the filtering process.
	49	!
	50	! 4294 2019-11-13 18:34:16Z suehring
[4294]	51	! Bugfix, always set bit 5 and 6 of wall_flags, indicating terrain- and
	52	! building surfaces in all cases, in order to enable terrain-following output
	53	! also when no land- or urban-surface model is applied.
	54	!
	55	! 4265 2019-10-15 16:16:24Z suehring
[4265]	56	! Bugfix for last commit, exchange oro_max variable only when it is allocated
	57	! (not necessarily the case when topography is input from ASCII file).
	58	!
	59	! 4245 2019-09-30 08:40:37Z pavelkrc
[4245]	60	! Store oro_max (building z-offset) in 2D for building surfaces
	61	!
	62	! 4189 2019-08-26 16:19:38Z suehring
[4189]	63	! - Add check for proper setting of namelist parameter topography
	64	! - Set flag to indicate land surfaces in case no topography is provided
	65	!
	66	! 4182 2019-08-22 15:20:23Z scharf
[4182]	67	! Corrected "Former revisions" section
	68	!
	69	! 4168 2019-08-16 13:50:17Z suehring
[4168]	70	! Pre-calculate topography top index and store it on an array (replaces former
	71	! functions get_topography_top_index)
	72	!
	73	! 4159 2019-08-15 13:31:35Z suehring
[4159]	74	! Revision of topography processing. This was not consistent between 2D and 3D
	75	! buildings.
	76	!
	77	! 4144 2019-08-06 09:11:47Z raasch
[4144]	78	! relational operators .EQ., .NE., etc. replaced by ==, /=, etc.
	79	!
	80	! 4115 2019-07-24 12:50:49Z suehring
[4115]	81	! Bugfix in setting near-surface flag 24, inidicating wall-bounded grid points
	82	!
	83	! 4110 2019-07-22 17:05:21Z suehring
[4110]	84	! - Separate initialization of advection flags for momentum and scalars.
	85	! - Change subroutine interface for ws_init_flags_scalar to pass boundary flags
	86	!
	87	! 4109 2019-07-22 17:00:34Z suehring
[3927]	88	! Fix bad commit
	89	!
	90	! 3926 2019-04-23 12:56:42Z suehring
[3925]	91	! Minor bugfix in building mapping when all building IDs in the model domain
	92	! are missing
	93	!
	94	! 3857 2019-04-03 13:00:16Z knoop
[3855]	95	! In projection of non-building 3D objects onto numerical grid remove
	96	! dependency on building_type
	97	!
	98	! 3763 2019-02-25 17:33:49Z suehring
[3763]	99	! Replace work-around for ghost point exchange of 1-byte arrays with specific
	100	! routine as already done in other routines
	101	!
	102	! 3761 2019-02-25 15:31:42Z raasch
[3761]	103	! unused variables removed
	104	!
	105	! 3661 2019-01-08 18:22:50Z suehring
[3661]	106	! Remove setting of nzb_max to nzt at non-cyclic boundary PEs, instead,
	107	! order degradation of advection scheme is handeled directly in advec_ws
	108	!
	109	! 3655 2019-01-07 16:51:22Z knoop
[3538]	110	! Comment added
[2716]	111	!
[4182]	112	! Revision 1.1 1997/08/11 06:17:45 raasch
	113	! Initial revision (Testversion)
	114	!
	115	!
[1]	116	! Description:
[2696]	117	! -----------------------------------------------------------------------------!
[1682]	118	!> Creating grid depending constants
[2696]	119	!> @todo: Rearrange topo flag list
	120	!> @todo: reference 3D buildings on top of orography is not tested and may need
	121	!> further improvement for steep slopes
	122	!> @todo: Use more advanced setting of building type at filled holes
[1]	123	!------------------------------------------------------------------------------!
[1682]	124	SUBROUTINE init_grid
	125
[1942]	126	USE advec_ws, &
[4109]	127	ONLY: ws_init_flags_momentum, ws_init_flags_scalar
[1]	128
[1320]	129	USE arrays_3d, &
[3857]	130	ONLY: dd2zu, ddzu, ddzu_pres, ddzw, dzu, dzw, x, xu, y, yv, zu, zw
[1320]	131
[1353]	132	USE control_parameters, &
[3761]	133	ONLY: bc_lr_cyc, bc_ns_cyc, &
[4109]	134	bc_dirichlet_l, &
	135	bc_dirichlet_n, &
	136	bc_dirichlet_r, &
	137	bc_dirichlet_s, &
	138	bc_radiation_l, &
	139	bc_radiation_n, &
	140	bc_radiation_r, &
	141	bc_radiation_s, &
[3241]	142	constant_flux_layer, dz, dz_max, dz_stretch_factor, &
[3065]	143	dz_stretch_factor_array, dz_stretch_level, dz_stretch_level_end,&
	144	dz_stretch_level_end_index, dz_stretch_level_start_index, &
[3241]	145	dz_stretch_level_start, ibc_uv_b, message_string, &
[3182]	146	momentum_advec, number_stretch_level_end, &
[3294]	147	number_stretch_level_start, ocean_mode, psolver, scalar_advec, &
[4340]	148	symmetry_flag, topography, use_surface_fluxes
[2021]	149
[1320]	150	USE grid_variables, &
[2232]	151	ONLY: ddx, ddx2, ddy, ddy2, dx, dx2, dy, dy2, zu_s_inner, zw_w_inner
[1320]	152
	153	USE indices, &
[4109]	154	ONLY: advc_flags_m, &
	155	advc_flags_s, &
	156	nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
[2232]	157	nzb, nzb_diff, nzb_diff_s_inner, nzb_diff_s_outer, &
	158	nzb_max, nzb_s_inner, nzb_s_outer, nzb_u_inner, &
[1845]	159	nzb_u_outer, nzb_v_inner, nzb_v_outer, nzb_w_inner, &
[4168]	160	nzb_w_outer, nzt, topo_top_ind, topo_min_level
[1320]	161
	162	USE kinds
[2696]	163
[1]	164	USE pegrid
	165
[2696]	166	USE poismg_noopt_mod
	167
[2232]	168	USE surface_mod, &
[4168]	169	ONLY: init_bc
[2232]	170
[2365]	171	USE vertical_nesting_mod, &
	172	ONLY: vnested, vnest_init_grid
	173
[1]	174	IMPLICIT NONE
	175
[3182]	176	INTEGER(iwp) :: i !< index variable along x
	177	INTEGER(iwp) :: j !< index variable along y
	178	INTEGER(iwp) :: k !< index variable along z
	179	INTEGER(iwp) :: k_top !< topography top index on local PE
	180	INTEGER(iwp) :: n !< loop variable for stretching
	181	INTEGER(iwp) :: number_dz !< number of user-specified dz values
	182	INTEGER(iwp) :: nzb_local_max !< vertical grid index of maximum topography height
	183	INTEGER(iwp) :: nzb_local_min !< vertical grid index of minimum topography height
[2232]	184
[3065]	185	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nzb_local !< index for topography top at cell-center
	186	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nzb_tmp !< dummy to calculate topography indices on u- and v-grid
[1]	187
[2696]	188	INTEGER(iwp), DIMENSION(:,:,:), ALLOCATABLE :: topo !< input array for 3D topography and dummy array for setting "outer"-flags
[2232]	189
[3065]	190	REAL(wp) :: dz_level_end !< distance between calculated height level for u/v-grid and user-specified end level for stretching
[1886]	191	REAL(wp) :: dz_stretched !< stretched vertical grid spacing
[3065]	192
	193	REAL(wp), DIMENSION(:), ALLOCATABLE :: min_dz_stretch_level_end !< Array that contains all minimum heights where the stretching can end
[861]	194
[1]	195
	196	!
[709]	197	!-- Calculation of horizontal array bounds including ghost layers
[667]	198	nxlg = nxl - nbgp
	199	nxrg = nxr + nbgp
	200	nysg = nys - nbgp
	201	nyng = nyn + nbgp
[709]	202
[667]	203	!
[1]	204	!-- Allocate grid arrays
[4386]	205	ALLOCATE( x(0:nx) )
	206	ALLOCATE( xu(0:nx) )
	207
[3857]	208	DO i = 0, nx
	209	xu(i) = i * dx
	210	x(i) = i * dx + 0.5_wp * dx
	211	ENDDO
	212
[4386]	213	ALLOCATE( y(0:ny) )
	214	ALLOCATE( yv(0:ny) )
	215
[3857]	216	DO j = 0, ny
	217	yv(j) = j * dy
	218	y(j) = j * dy + 0.5_wp * dy
	219	ENDDO
	220
[4386]	221	ALLOCATE( ddzu(1:nzt+1) )
	222	ALLOCATE( ddzw(1:nzt+1) )
	223	ALLOCATE( dd2zu(1:nzt) )
	224	ALLOCATE( dzu(1:nzt+1) )
	225	ALLOCATE( dzw(1:nzt+1) )
	226	ALLOCATE( zu(nzb:nzt+1) )
	227	ALLOCATE( zw(nzb:nzt+1) )
[1]	228
	229	!
[4386]	230	!-- For constructing an appropriate grid, the vertical grid spacing dz has to
	231	!-- be specified with a non-negative value in the parameter file
[3065]	232	IF ( dz(1) == -1.0_wp ) THEN
[254]	233	message_string = 'missing dz'
	234	CALL message( 'init_grid', 'PA0200', 1, 2, 0, 6, 0 )
[3065]	235	ELSEIF ( dz(1) <= 0.0_wp ) THEN
	236	WRITE( message_string, * ) 'dz=',dz(1),' <= 0.0'
[254]	237	CALL message( 'init_grid', 'PA0201', 1, 2, 0, 6, 0 )
[1]	238	ENDIF
[94]	239
[1]	240	!
[3065]	241	!-- Initialize dz_stretch_level_start with the value of dz_stretch_level
	242	!-- if it was set by the user
	243	IF ( dz_stretch_level /= -9999999.9_wp ) THEN
	244	dz_stretch_level_start(1) = dz_stretch_level
	245	ENDIF
	246
	247	!
	248	!-- Determine number of dz values and stretching levels specified by the
	249	!-- user to allow right controlling of the stretching mechanism and to
[3139]	250	!-- perform error checks. The additional requirement that dz /= dz_max
	251	!-- for counting number of user-specified dz values is necessary. Otherwise
	252	!-- restarts would abort if the old stretching mechanism with dz_stretch_level
	253	!-- is used (Attention: The user is not allowed to specify a dz value equal
	254	!-- to the default of dz_max = 999.0).
	255	number_dz = COUNT( dz /= -1.0_wp .AND. dz /= dz_max)
[3065]	256	number_stretch_level_start = COUNT( dz_stretch_level_start /= &
	257	-9999999.9_wp )
	258	number_stretch_level_end = COUNT( dz_stretch_level_end /= &
	259	9999999.9_wp )
	260
	261	!
[4386]	262	!-- The number of specified end levels +1 has to be the same as the number
[3065]	263	!-- of specified dz values
	264	IF ( number_dz /= number_stretch_level_end + 1 ) THEN
[4386]	265	WRITE( message_string, * ) 'The number of values for dz = ', &
	266	number_dz, 'has to be the same as& ', &
	267	'the number of values for ', &
	268	'dz_stretch_level_end + 1 = ', &
[3065]	269	number_stretch_level_end+1
	270	CALL message( 'init_grid', 'PA0156', 1, 2, 0, 6, 0 )
	271	ENDIF
	272
	273	!
[4386]	274	!-- The number of specified start levels has to be the same or one less than
	275	!-- the number of specified dz values
	276	IF ( number_dz /= number_stretch_level_start + 1 .AND. &
[3065]	277	number_dz /= number_stretch_level_start ) THEN
[4386]	278	WRITE( message_string, * ) 'The number of values for dz = ', &
	279	number_dz, 'has to be the same as or one ', &
	280	'more than& the number of values for ', &
	281	'dz_stretch_level_start = ', &
[3065]	282	number_stretch_level_start
	283	CALL message( 'init_grid', 'PA0211', 1, 2, 0, 6, 0 )
	284	ENDIF
	285
[4386]	286	!-- The number of specified start levels has to be the same or one more than
	287	!-- the number of specified end levels
	288	IF ( number_stretch_level_start /= number_stretch_level_end + 1 .AND. &
[3065]	289	number_stretch_level_start /= number_stretch_level_end ) THEN
[4386]	290	WRITE( message_string, * ) 'The number of values for ', &
	291	'dz_stretch_level_start = ', &
	292	dz_stretch_level_start, 'has to be the ', &
	293	'same or one more than& the number of ', &
	294	'values for dz_stretch_level_end = ', &
[3065]	295	number_stretch_level_end
	296	CALL message( 'init_grid', 'PA0216', 1, 2, 0, 6, 0 )
	297	ENDIF
	298
	299	!
	300	!-- Initialize dz for the free atmosphere with the value of dz_max
	301	IF ( dz(number_stretch_level_start+1) == -1.0_wp .AND. &
	302	number_stretch_level_start /= 0 ) THEN
	303	dz(number_stretch_level_start+1) = dz_max
	304	ENDIF
	305
	306	!
	307	!-- Initialize the stretching factor if (infinitely) stretching in the free
	308	!-- atmosphere is desired (dz_stretch_level_end was not specified for the
	309	!-- free atmosphere)
	310	IF ( number_stretch_level_start == number_stretch_level_end + 1 ) THEN
	311	dz_stretch_factor_array(number_stretch_level_start) = &
	312	dz_stretch_factor
	313	ENDIF
	314
	315	!
	316	!-- Allocation of arrays for stretching
	317	ALLOCATE( min_dz_stretch_level_end(number_stretch_level_start) )
[3066]	318
[3065]	319	!
[4386]	320	!-- Define the vertical grid levels. Start with atmosphere branch
[3294]	321	IF ( .NOT. ocean_mode ) THEN
[3065]	322
[94]	323	!
[3065]	324	!-- The stretching region has to be large enough to allow for a smooth
[4386]	325	!-- transition between two different grid spacings. The number 4 is an
	326	!-- empirical value
[3065]	327	DO n = 1, number_stretch_level_start
	328	min_dz_stretch_level_end(n) = dz_stretch_level_start(n) + &
	329	4 * MAX( dz(n),dz(n+1) )
	330	ENDDO
	331
[3066]	332	IF ( ANY( min_dz_stretch_level_end(1:number_stretch_level_start) > &
	333	dz_stretch_level_end(1:number_stretch_level_start) ) ) THEN
[4386]	334	message_string= 'Each dz_stretch_level_end has to be larger ' // &
[3065]	335	'than its corresponding value for &' // &
	336	'dz_stretch_level_start + 4*MAX(dz(n),dz(n+1)) '//&
	337	'to allow for smooth grid stretching'
	338	CALL message( 'init_grid', 'PA0224', 1, 2, 0, 6, 0 )
	339	ENDIF
	340
	341	!
[4386]	342	!-- Stretching must not be applied within the surface layer
[3065]	343	!-- (first two grid points). For the default case dz_stretch_level_start
	344	!-- is negative. Therefore the absolut value is checked here.
[4386]	345	IF ( ANY( ABS( dz_stretch_level_start ) <= dz(1) * 1.5_wp ) ) THEN
	346	WRITE( message_string, * ) 'Each dz_stretch_level_start has to be ',&
[3065]	347	'larger than ', dz(1) * 1.5
	348	CALL message( 'init_grid', 'PA0226', 1, 2, 0, 6, 0 )
	349	ENDIF
	350
	351	!
	352	!-- The stretching has to start and end on a grid level. Therefore
[4386]	353	!-- user-specified values are mapped to the next lowest level. The
	354	!-- calculation of the first level is realized differently just because of
	355	!-- historical reasons (the advanced/new stretching mechanism was realized
	356	!-- in a way that results don't change if the old parameters
	357	!-- dz_stretch_level, dz_stretch_factor and dz_max are used)
[3065]	358	IF ( number_stretch_level_start /= 0 ) THEN
	359	dz_stretch_level_start(1) = INT( (dz_stretch_level_start(1) - &
	360	dz(1)/2.0) / dz(1) ) &
	361	* dz(1) + dz(1)/2.0
	362	ENDIF
	363
	364	IF ( number_stretch_level_start > 1 ) THEN
	365	DO n = 2, number_stretch_level_start
	366	dz_stretch_level_start(n) = INT( dz_stretch_level_start(n) / &
	367	dz(n) ) * dz(n)
	368	ENDDO
	369	ENDIF
	370
	371	IF ( number_stretch_level_end /= 0 ) THEN
	372	DO n = 1, number_stretch_level_end
	373	dz_stretch_level_end(n) = INT( dz_stretch_level_end(n) / &
	374	dz(n+1) ) * dz(n+1)
	375	ENDDO
	376	ENDIF
[4386]	377
[3065]	378	!
	379	!-- Determine stretching factor if necessary
	380	IF ( number_stretch_level_end >= 1 ) THEN
	381	CALL calculate_stretching_factor( number_stretch_level_end )
	382	ENDIF
	383
	384	!
[94]	385	!-- Grid for atmosphere with surface at z=0 (k=0, w-grid).
[3065]	386	!-- First compute the u- and v-levels. In case of dirichlet bc for u and v
	387	!-- the first u/v- and w-level (k=0) are defined at same height (z=0).
[843]	388	!-- The second u-level (k=1) corresponds to the top of the
[4386]	389	!-- surface layer. In case of symmetric boundaries (closed channel flow),
[4340]	390	!-- the first grid point is always at z=0.
	391	IF ( ibc_uv_b == 0 .OR. ibc_uv_b == 2 .OR. &
	392	topography == 'closed_channel' ) THEN
[1353]	393	zu(0) = 0.0_wp
[667]	394	ELSE
[3065]	395	zu(0) = - dz(1) * 0.5_wp
[667]	396	ENDIF
[3065]	397
	398	zu(1) = dz(1) * 0.5_wp
	399
	400	!
	401	!-- Determine u and v height levels considering the possibility of grid
	402	!-- stretching in several heights.
	403	n = 1
	404	dz_stretch_level_start_index = nzt+1
	405	dz_stretch_level_end_index = nzt+1
	406	dz_stretched = dz(1)
[1]	407
[3065]	408	!-- The default value of dz_stretch_level_start is negative, thus the first
[4386]	409	!-- condition is true even if no stretching shall be applied. Hence, the
	410	!-- second condition is also necessary.
[4340]	411	DO k = 2, nzt+1-symmetry_flag
[3065]	412	IF ( dz_stretch_level_start(n) <= zu(k-1) .AND. &
	413	dz_stretch_level_start(n) /= -9999999.9_wp ) THEN
	414	dz_stretched = dz_stretched * dz_stretch_factor_array(n)
	415
	416	IF ( dz(n) > dz(n+1) ) THEN
	417	dz_stretched = MAX( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (higher) dz
	418	ELSE
	419	dz_stretched = MIN( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (lower) dz
	420	ENDIF
	421
	422	IF ( dz_stretch_level_start_index(n) == nzt+1 ) &
	423	dz_stretch_level_start_index(n) = k-1
	424
[94]	425	ENDIF
[3065]	426
[94]	427	zu(k) = zu(k-1) + dz_stretched
[3065]	428
	429	!
	430	!-- Make sure that the stretching ends exactly at dz_stretch_level_end
	431	dz_level_end = ABS( zu(k) - dz_stretch_level_end(n) )
	432
	433	IF ( dz_level_end < dz(n+1)/3.0 ) THEN
	434	zu(k) = dz_stretch_level_end(n)
	435	dz_stretched = dz(n+1)
	436	dz_stretch_level_end_index(n) = k
	437	n = n + 1
	438	ENDIF
[94]	439	ENDDO
[4340]	440
	441	!
	442	!-- If a closed channel flow is simulated, make sure that grid structure is
	443	!-- the same for both bottom and top boundary. (Hint: Using a different dz
	444	!-- at the bottom and at the top makes no sense due to symmetric boundaries
	445	!-- where dz should be equal. Therefore, different dz at the bottom and top
	446	!-- causes an abort (see check_parameters).)
	447	IF ( topography == 'closed_channel' ) THEN
	448	zu(nzt+1) = zu(nzt) + dz(1) * 0.5_wp
	449	ENDIF
[1]	450
	451	!
[94]	452	!-- Compute the w-levels. They are always staggered half-way between the
[843]	453	!-- corresponding u-levels. In case of dirichlet bc for u and v at the
	454	!-- ground the first u- and w-level (k=0) are defined at same height (z=0).
[4340]	455	!-- Per default, the top w-level is extrapolated linearly. In case of
	456	!-- a closed channel flow, zu(nzt+1) and zw(nzt) must be set explicitely.
	457	!-- (Hint: Using a different dz at the bottom and at the top makes no sense
	458	!-- due to symmetric boundaries where dz should be equal. Therefore,
	459	!-- different dz at the bottom and top causes an abort (see
	460	!-- check_parameters).)
[1353]	461	zw(0) = 0.0_wp
[4340]	462	DO k = 1, nzt-symmetry_flag
[1353]	463	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	464	ENDDO
[4340]	465	IF ( topography == 'closed_channel' ) THEN
	466	zw(nzt) = zw(nzt-1) + dz(1)
	467	zw(nzt+1) = zw(nzt) + dz(1)
	468	ELSE
	469	zw(nzt+1) = zw(nzt) + 2.0_wp * ( zu(nzt+1) - zw(nzt) )
	470	ENDIF
[1]	471
[4386]	472	ELSE !ocean branch
[3065]	473
[1]	474	!
[3065]	475	!-- The stretching region has to be large enough to allow for a smooth
[4386]	476	!-- transition between two different grid spacings. The number 4 is an
	477	!-- empirical value
[3065]	478	DO n = 1, number_stretch_level_start
	479	min_dz_stretch_level_end(n) = dz_stretch_level_start(n) - &
	480	4 * MAX( dz(n),dz(n+1) )
	481	ENDDO
	482
[3066]	483	IF ( ANY( min_dz_stretch_level_end (1:number_stretch_level_start) < &
	484	dz_stretch_level_end(1:number_stretch_level_start) ) ) THEN
[4386]	485	message_string= 'Each dz_stretch_level_end has to be less ' // &
[3065]	486	'than its corresponding value for &' // &
	487	'dz_stretch_level_start - 4*MAX(dz(n),dz(n+1)) '//&
	488	'to allow for smooth grid stretching'
	489	CALL message( 'init_grid', 'PA0224', 1, 2, 0, 6, 0 )
	490	ENDIF
	491
	492	!
[3068]	493	!-- Stretching must not be applied close to the surface (last two grid
	494	!-- points). For the default case dz_stretch_level_start is negative.
[4386]	495	IF ( ANY( dz_stretch_level_start >= - dz(1) * 1.5_wp ) ) THEN
	496	WRITE( message_string, * ) 'Each dz_stretch_level_start has to be ',&
	497	'less than ', -dz(1) * 1.5
[3065]	498	CALL message( 'init_grid', 'PA0226', 1, 2, 0, 6, 0 )
	499	ENDIF
	500
	501	!
	502	!-- The stretching has to start and end on a grid level. Therefore
[4386]	503	!-- user-specified values are mapped to the next highest level. The
	504	!-- calculation of the first level is realized differently just because of
	505	!-- historical reasons (the advanced/new stretching mechanism was realized
	506	!-- in a way that results don't change if the old parameters
	507	!-- dz_stretch_level, dz_stretch_factor and dz_max are used)
[3065]	508	IF ( number_stretch_level_start /= 0 ) THEN
	509	dz_stretch_level_start(1) = INT( (dz_stretch_level_start(1) + &
	510	dz(1)/2.0) / dz(1) ) &
	511	* dz(1) - dz(1)/2.0
	512	ENDIF
	513
	514	IF ( number_stretch_level_start > 1 ) THEN
	515	DO n = 2, number_stretch_level_start
	516	dz_stretch_level_start(n) = INT( dz_stretch_level_start(n) / &
	517	dz(n) ) * dz(n)
	518	ENDDO
	519	ENDIF
	520
	521	IF ( number_stretch_level_end /= 0 ) THEN
	522	DO n = 1, number_stretch_level_end
	523	dz_stretch_level_end(n) = INT( dz_stretch_level_end(n) / &
	524	dz(n+1) ) * dz(n+1)
	525	ENDDO
	526	ENDIF
	527
	528	!
	529	!-- Determine stretching factor if necessary
	530	IF ( number_stretch_level_end >= 1 ) THEN
	531	CALL calculate_stretching_factor( number_stretch_level_end )
	532	ENDIF
	533
	534	!
[843]	535	!-- Grid for ocean with free water surface is at k=nzt (w-grid).
	536	!-- In case of neumann bc at the ground the first first u-level (k=0) lies
	537	!-- below the first w-level (k=0). In case of dirichlet bc the first u- and
	538	!-- w-level are defined at same height, but staggered from the second level.
[4386]	539	!-- The second u-level (k=1) corresponds to the top of the surface layer.
[3065]	540	!-- z values are negative starting from z=0 (surface)
	541	zu(nzt+1) = dz(1) * 0.5_wp
	542	zu(nzt) = - dz(1) * 0.5_wp
[94]	543
[3065]	544	!
	545	!-- Determine u and v height levels considering the possibility of grid
	546	!-- stretching in several heights.
	547	n = 1
	548	dz_stretch_level_start_index = 0
	549	dz_stretch_level_end_index = 0
	550	dz_stretched = dz(1)
	551
[94]	552	DO k = nzt-1, 0, -1
[3065]	553
	554	IF ( dz_stretch_level_start(n) >= zu(k+1) ) THEN
	555	dz_stretched = dz_stretched * dz_stretch_factor_array(n)
	556
	557	IF ( dz(n) > dz(n+1) ) THEN
	558	dz_stretched = MAX( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (higher) dz
	559	ELSE
	560	dz_stretched = MIN( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (lower) dz
	561	ENDIF
	562
	563	IF ( dz_stretch_level_start_index(n) == 0 ) &
	564	dz_stretch_level_start_index(n) = k+1
	565
	566	ENDIF
	567
	568	zu(k) = zu(k+1) - dz_stretched
	569
[1418]	570	!
[3065]	571	!-- Make sure that the stretching ends exactly at dz_stretch_level_end
	572	dz_level_end = ABS( zu(k) - dz_stretch_level_end(n) )
	573
	574	IF ( dz_level_end < dz(n+1)/3.0 ) THEN
	575	zu(k) = dz_stretch_level_end(n)
	576	dz_stretched = dz(n+1)
	577	dz_stretch_level_end_index(n) = k
	578	n = n + 1
[94]	579	ENDIF
	580	ENDDO
[3065]	581
[94]	582	!
	583	!-- Compute the w-levels. They are always staggered half-way between the
[843]	584	!-- corresponding u-levels, except in case of dirichlet bc for u and v
	585	!-- at the ground. In this case the first u- and w-level are defined at
	586	!-- same height. The top w-level (nzt+1) is not used but set for
	587	!-- consistency, since w and all scalar variables are defined up tp nzt+1.
[3065]	588	zw(nzt+1) = dz(1)
[1353]	589	zw(nzt) = 0.0_wp
[94]	590	DO k = 0, nzt
[1353]	591	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	592	ENDDO
	593
[843]	594	!
	595	!-- In case of dirichlet bc for u and v the first u- and w-level are defined
	596	!-- at same height.
	597	IF ( ibc_uv_b == 0 ) THEN
	598	zu(0) = zw(0)
	599	ENDIF
	600
[4386]	601	ENDIF !End of defining the vertical grid levels
[94]	602
	603	!
[1]	604	!-- Compute grid lengths.
	605	DO k = 1, nzt+1
	606	dzu(k) = zu(k) - zu(k-1)
[1353]	607	ddzu(k) = 1.0_wp / dzu(k)
[1]	608	dzw(k) = zw(k) - zw(k-1)
[1353]	609	ddzw(k) = 1.0_wp / dzw(k)
[1]	610	ENDDO
	611
	612	DO k = 1, nzt
[1353]	613	dd2zu(k) = 1.0_wp / ( dzu(k) + dzu(k+1) )
[1]	614	ENDDO
[667]	615
	616	!
[709]	617	!-- The FFT- SOR-pressure solvers assume grid spacings of a staggered grid
	618	!-- everywhere. For the actual grid, the grid spacing at the lowest level
	619	!-- is only dz/2, but should be dz. Therefore, an additional array
	620	!-- containing with appropriate grid information is created for these
	621	!-- solvers.
[1575]	622	IF ( psolver(1:9) /= 'multigrid' ) THEN
[667]	623	ALLOCATE( ddzu_pres(1:nzt+1) )
	624	ddzu_pres = ddzu
[864]	625	ddzu_pres(1) = ddzu_pres(2) ! change for lowest level
[1]	626	ENDIF
	627
	628	!
	629	!-- Compute the reciprocal values of the horizontal grid lengths.
[1353]	630	ddx = 1.0_wp / dx
	631	ddy = 1.0_wp / dy
[1]	632	dx2 = dx * dx
	633	dy2 = dy * dy
[1353]	634	ddx2 = 1.0_wp / dx2
	635	ddy2 = 1.0_wp / dy2
[1]	636
	637	!
[2696]	638	!-- Allocate 3D array to set topography
	639	ALLOCATE( topo(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	640	topo = 0
	641	!
[4386]	642	!-- Initialize topography by generic topography or read topography from file.
[2696]	643	CALL init_topo( topo )
	644	!
	645	!-- Set flags to mask topography on the grid.
	646	CALL set_topo_flags( topo )
	647	!
	648	!-- Calculate wall flag arrays for the multigrid method.
	649	!-- Please note, wall flags are only applied in the non-optimized version.
[4109]	650	IF ( psolver == 'multigrid_noopt' ) CALL poismg_noopt_init
[2696]	651
	652	!
	653	!-- Init flags for ws-scheme to degrade order of the numerics near walls, i.e.
[4109]	654	!-- to decrease the numerical stencil appropriately. The order of the scheme
	655	!-- is degraded near solid walls as well as near non-cyclic inflow and outflow
	656	!-- boundaries. Do this separately for momentum and scalars.
	657	IF ( momentum_advec == 'ws-scheme' ) THEN
	658	ALLOCATE( advc_flags_m(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	659	CALL ws_init_flags_momentum
	660	ENDIF
	661	IF ( scalar_advec == 'ws-scheme' ) THEN
	662	ALLOCATE( advc_flags_s(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	663	advc_flags_s = 0
	664
	665	CALL ws_init_flags_scalar( bc_dirichlet_l .OR. bc_radiation_l, &
	666	bc_dirichlet_n .OR. bc_radiation_n, &
	667	bc_dirichlet_r .OR. bc_radiation_r, &
	668	bc_dirichlet_s .OR. bc_radiation_s, &
	669	advc_flags_s )
	670	ENDIF
[2696]	671
	672	!
	673	!-- Determine the maximum level of topography. It is used for
	674	!-- steering the degradation of order of the applied advection scheme,
[4328]	675	!-- as well in the lpm.
[2696]	676	k_top = 0
	677	DO i = nxl, nxr
	678	DO j = nys, nyn
	679	DO k = nzb, nzt + 1
[4109]	680	k_top = MAX( k_top, MERGE( k, 0, .NOT. BTEST( topo(k,j,i), 0 ) ) )
[2696]	681	ENDDO
	682	ENDDO
[1]	683	ENDDO
[2696]	684	#if defined( __parallel )
[4328]	685	CALL MPI_ALLREDUCE( k_top, nzb_max, 1, MPI_INTEGER, &
[2696]	686	MPI_MAX, comm2d, ierr )
	687	#else
[4328]	688	nzb_max = k_top
[2696]	689	#endif
[1]	690	!
[4328]	691	!-- Increment nzb_max by 1 in order to allow for proper diverengence correction.
	692	!-- Further, in case topography extents up to the model top, limit to nzt.
	693	nzb_max = MIN( nzb_max+1, nzt )
	694	!
[2968]	695	!-- Determine minimum index of topography. Usually, this will be nzb. In case
	696	!-- there is elevated topography, however, the lowest topography will be higher.
	697	!-- This index is e.g. used to calculate mean first-grid point atmosphere
	698	!-- temperature, surface pressure and density, etc. .
	699	topo_min_level = 0
	700	#if defined( __parallel )
[4168]	701	CALL MPI_ALLREDUCE( MINVAL( topo_top_ind(nys:nyn,nxl:nxr,0) ), &
[2968]	702	topo_min_level, 1, MPI_INTEGER, MPI_MIN, comm2d, ierr )
	703	#else
[4168]	704	topo_min_level = MINVAL( topo_top_ind(nys:nyn,nxl:nxr,0) )
[2968]	705	#endif
	706	!
[2696]	707	!-- Initialize boundary conditions via surface type
	708	CALL init_bc
[3182]	709
[2696]	710	!
	711	!-- Allocate and set topography height arrays required for data output
	712	IF ( TRIM( topography ) /= 'flat' ) THEN
	713	!
	714	!-- Allocate and set the arrays containing the topography height
	715	IF ( nxr == nx .AND. nyn /= ny ) THEN
[4386]	716	ALLOCATE( zu_s_inner(nxl:nxr+1,nys:nyn) )
	717	ALLOCATE( zw_w_inner(nxl:nxr+1,nys:nyn) )
[2696]	718	ELSEIF ( nxr /= nx .AND. nyn == ny ) THEN
[4386]	719	ALLOCATE( zu_s_inner(nxl:nxr,nys:nyn+1) )
	720	ALLOCATE( zw_w_inner(nxl:nxr,nys:nyn+1) )
[2696]	721	ELSEIF ( nxr == nx .AND. nyn == ny ) THEN
[4386]	722	ALLOCATE( zu_s_inner(nxl:nxr+1,nys:nyn+1) )
	723	ALLOCATE( zw_w_inner(nxl:nxr+1,nys:nyn+1) )
[2696]	724	ELSE
[4386]	725	ALLOCATE( zu_s_inner(nxl:nxr,nys:nyn) )
	726	ALLOCATE( zw_w_inner(nxl:nxr,nys:nyn) )
[2696]	727	ENDIF
	728
	729	zu_s_inner = 0.0_wp
	730	zw_w_inner = 0.0_wp
	731	!
	732	!-- Determine local topography height on scalar and w-grid. Note, setting
[4329]	733	!-- lateral boundary values is not necessary, realized via wall_flags_static_0
[2696]	734	!-- array. Further, please note that loop bounds are different from
	735	!-- nxl to nxr and nys to nyn on south and right model boundary, hence,
	736	!-- use intrinsic lbound and ubound functions to infer array bounds.
	737	DO i = LBOUND(zu_s_inner, 1), UBOUND(zu_s_inner, 1)
	738	DO j = LBOUND(zu_s_inner, 2), UBOUND(zu_s_inner, 2)
	739	!
	740	!-- Topography height on scalar grid. Therefore, determine index of
	741	!-- upward-facing surface element on scalar grid.
[4168]	742	zu_s_inner(i,j) = zu(topo_top_ind(j,i,0))
[2696]	743	!
	744	!-- Topography height on w grid. Therefore, determine index of
	745	!-- upward-facing surface element on w grid.
[4168]	746	zw_w_inner(i,j) = zw(topo_top_ind(j,i,3))
[2696]	747	ENDDO
	748	ENDDO
	749	ENDIF
	750
	751	!
	752	!-- In the following, calculate 2D index arrays. Note, these will be removed
	753	!-- soon.
[1]	754	!-- Allocate outer and inner index arrays for topography and set
[2232]	755	!-- defaults.
[4386]	756	ALLOCATE( nzb_s_inner(nysg:nyng,nxlg:nxrg) )
	757	ALLOCATE( nzb_s_outer(nysg:nyng,nxlg:nxrg) )
	758	ALLOCATE( nzb_u_inner(nysg:nyng,nxlg:nxrg) )
	759	ALLOCATE( nzb_u_outer(nysg:nyng,nxlg:nxrg) )
	760	ALLOCATE( nzb_v_inner(nysg:nyng,nxlg:nxrg) )
	761	ALLOCATE( nzb_v_outer(nysg:nyng,nxlg:nxrg) )
	762	ALLOCATE( nzb_w_inner(nysg:nyng,nxlg:nxrg) )
	763	ALLOCATE( nzb_w_outer(nysg:nyng,nxlg:nxrg) )
	764	ALLOCATE( nzb_diff_s_inner(nysg:nyng,nxlg:nxrg) )
	765	ALLOCATE( nzb_diff_s_outer(nysg:nyng,nxlg:nxrg) )
	766	ALLOCATE( nzb_local(nysg:nyng,nxlg:nxrg) )
	767	ALLOCATE( nzb_tmp(nysg:nyng,nxlg:nxrg) )
[2696]	768	!
	769	!-- Initialize 2D-index arrays. Note, these will be removed soon!
[4168]	770	nzb_local(nys:nyn,nxl:nxr) = topo_top_ind(nys:nyn,nxl:nxr,0)
[2696]	771	CALL exchange_horiz_2d_int( nzb_local, nys, nyn, nxl, nxr, nbgp )
[2968]	772	!
	773	!-- Check topography for consistency with model domain. Therefore, use
	774	!-- maximum and minium topography-top indices. Note, minimum topography top
	775	!-- index is already calculated.
[2696]	776	IF ( TRIM( topography ) /= 'flat' ) THEN
	777	#if defined( __parallel )
[4168]	778	CALL MPI_ALLREDUCE( MAXVAL( topo_top_ind(nys:nyn,nxl:nxr,0) ), &
[3182]	779	nzb_local_max, 1, MPI_INTEGER, MPI_MAX, comm2d, ierr )
[2696]	780	#else
[4168]	781	nzb_local_max = MAXVAL( topo_top_ind(nys:nyn,nxl:nxr,0) )
[2696]	782	#endif
[2968]	783	nzb_local_min = topo_min_level
[2696]	784	!
	785	!-- Consistency checks
	786	IF ( nzb_local_min < 0 .OR. nzb_local_max > nz + 1 ) THEN
	787	WRITE( message_string, * ) 'nzb_local values are outside the', &
[3045]	788	' model domain', &
[3046]	789	'&MINVAL( nzb_local ) = ', nzb_local_min, &
	790	'&MAXVAL( nzb_local ) = ', nzb_local_max
[2696]	791	CALL message( 'init_grid', 'PA0210', 1, 2, 0, 6, 0 )
	792	ENDIF
	793	ENDIF
[1]	794
	795	nzb_s_inner = nzb; nzb_s_outer = nzb
	796	nzb_u_inner = nzb; nzb_u_outer = nzb
	797	nzb_v_inner = nzb; nzb_v_outer = nzb
	798	nzb_w_inner = nzb; nzb_w_outer = nzb
	799
	800	!
[19]	801	!-- Define vertical gridpoint from (or to) which on the usual finite difference
[1]	802	!-- form (which does not use surface fluxes) is applied
[1691]	803	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[1]	804	nzb_diff = nzb + 2
	805	ELSE
	806	nzb_diff = nzb + 1
	807	ENDIF
	808
	809	nzb_diff_s_inner = nzb_diff; nzb_diff_s_outer = nzb_diff
[2696]	810	!
	811	!-- Set Neumann conditions for topography. Will be removed soon.
	812	IF ( .NOT. bc_ns_cyc ) THEN
	813	IF ( nys == 0 ) THEN
[2927]	814	DO i = 1, nbgp
	815	nzb_local(nys-i,:) = nzb_local(nys,:)
	816	ENDDO
[2696]	817	ELSEIF ( nyn == ny ) THEN
[2927]	818	DO i = 1, nbgp
	819	nzb_local(ny+i,:) = nzb_local(ny,:)
	820	ENDDO
[2696]	821	ENDIF
	822	ENDIF
[1]	823
[2696]	824	IF ( .NOT. bc_lr_cyc ) THEN
	825	IF ( nxl == 0 ) THEN
[2927]	826	DO i = 1, nbgp
	827	nzb_local(:,nxl-i) = nzb_local(:,nxl)
	828	ENDDO
[2696]	829	ELSEIF ( nxr == nx ) THEN
[2927]	830	DO i = 1, nbgp
	831	nzb_local(:,nx+i) = nzb_local(:,nx)
	832	ENDDO
[2696]	833	ENDIF
	834	ENDIF
[1]	835	!
[2696]	836	!-- Initialization of 2D index arrays, will be removed soon!
	837	!-- Initialize nzb_s_inner and nzb_w_inner
	838	nzb_s_inner = nzb_local
	839	nzb_w_inner = nzb_local
	840
	841	!
	842	!-- Initialize remaining index arrays:
	843	!-- first pre-initialize them with nzb_s_inner...
	844	nzb_u_inner = nzb_s_inner
	845	nzb_u_outer = nzb_s_inner
	846	nzb_v_inner = nzb_s_inner
	847	nzb_v_outer = nzb_s_inner
	848	nzb_w_outer = nzb_s_inner
	849	nzb_s_outer = nzb_s_inner
	850
	851	!
	852	!-- nzb_s_outer:
	853	!-- extend nzb_local east-/westwards first, then north-/southwards
	854	nzb_tmp = nzb_local
	855	DO j = nys, nyn
	856	DO i = nxl, nxr
	857	nzb_tmp(j,i) = MAX( nzb_local(j,i-1), nzb_local(j,i), &
	858	nzb_local(j,i+1) )
	859	ENDDO
	860	ENDDO
	861
	862	CALL exchange_horiz_2d_int( nzb_tmp, nys, nyn, nxl, nxr, nbgp )
	863
	864	DO i = nxl, nxr
	865	DO j = nys, nyn
	866	nzb_s_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i), &
	867	nzb_tmp(j+1,i) )
	868	ENDDO
	869	!
	870	!-- non-cyclic boundary conditions (overwritten by call of
	871	!-- exchange_horiz_2d_int below in case of cyclic boundary conditions)
	872	IF ( nys == 0 ) THEN
	873	j = -1
	874	nzb_s_outer(j,i) = MAX( nzb_tmp(j+1,i), nzb_tmp(j,i) )
	875	ENDIF
	876	IF ( nyn == ny ) THEN
	877	j = ny + 1
	878	nzb_s_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i) )
	879	ENDIF
	880	ENDDO
	881	!
	882	!-- nzb_w_outer:
	883	!-- identical to nzb_s_outer
	884	nzb_w_outer = nzb_s_outer
	885	!
	886	!-- nzb_u_inner:
	887	!-- extend nzb_local rightwards only
	888	nzb_tmp = nzb_local
	889	DO j = nys, nyn
	890	DO i = nxl, nxr
	891	nzb_tmp(j,i) = MAX( nzb_local(j,i-1), nzb_local(j,i) )
	892	ENDDO
	893	ENDDO
	894
	895	CALL exchange_horiz_2d_int( nzb_tmp, nys, nyn, nxl, nxr, nbgp )
	896
	897	nzb_u_inner = nzb_tmp
	898	!
	899	!-- nzb_u_outer:
	900	!-- extend current nzb_tmp (nzb_u_inner) north-/southwards
	901	DO i = nxl, nxr
	902	DO j = nys, nyn
	903	nzb_u_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i), &
	904	nzb_tmp(j+1,i) )
	905	ENDDO
	906	!
	907	!-- non-cyclic boundary conditions (overwritten by call of
	908	!-- exchange_horiz_2d_int below in case of cyclic boundary conditions)
	909	IF ( nys == 0 ) THEN
	910	j = -1
	911	nzb_u_outer(j,i) = MAX( nzb_tmp(j+1,i), nzb_tmp(j,i) )
	912	ENDIF
	913	IF ( nyn == ny ) THEN
	914	j = ny + 1
	915	nzb_u_outer(j,i) = MAX( nzb_tmp(j-1,i), nzb_tmp(j,i) )
	916	ENDIF
	917	ENDDO
	918
	919	!
	920	!-- nzb_v_inner:
	921	!-- extend nzb_local northwards only
	922	nzb_tmp = nzb_local
	923	DO i = nxl, nxr
	924	DO j = nys, nyn
	925	nzb_tmp(j,i) = MAX( nzb_local(j-1,i), nzb_local(j,i) )
	926	ENDDO
	927	ENDDO
	928
	929	CALL exchange_horiz_2d_int( nzb_tmp, nys, nyn, nxl, nxr, nbgp )
	930	nzb_v_inner = nzb_tmp
	931
	932	!
	933	!-- nzb_v_outer:
	934	!-- extend current nzb_tmp (nzb_v_inner) right-/leftwards
	935	DO j = nys, nyn
	936	DO i = nxl, nxr
	937	nzb_v_outer(j,i) = MAX( nzb_tmp(j,i-1), nzb_tmp(j,i), &
	938	nzb_tmp(j,i+1) )
	939	ENDDO
	940	!
	941	!-- non-cyclic boundary conditions (overwritten by call of
	942	!-- exchange_horiz_2d_int below in case of cyclic boundary conditions)
	943	IF ( nxl == 0 ) THEN
	944	i = -1
	945	nzb_v_outer(j,i) = MAX( nzb_tmp(j,i+1), nzb_tmp(j,i) )
	946	ENDIF
	947	IF ( nxr == nx ) THEN
	948	i = nx + 1
	949	nzb_v_outer(j,i) = MAX( nzb_tmp(j,i-1), nzb_tmp(j,i) )
	950	ENDIF
	951	ENDDO
	952
	953	!
	954	!-- Exchange of lateral boundary values (parallel computers) and cyclic
	955	!-- boundary conditions, if applicable.
	956	!-- Since nzb_s_inner and nzb_w_inner are derived directly from nzb_local
	957	!-- they do not require exchange and are not included here.
	958	CALL exchange_horiz_2d_int( nzb_u_inner, nys, nyn, nxl, nxr, nbgp )
	959	CALL exchange_horiz_2d_int( nzb_u_outer, nys, nyn, nxl, nxr, nbgp )
	960	CALL exchange_horiz_2d_int( nzb_v_inner, nys, nyn, nxl, nxr, nbgp )
	961	CALL exchange_horiz_2d_int( nzb_v_outer, nys, nyn, nxl, nxr, nbgp )
	962	CALL exchange_horiz_2d_int( nzb_w_outer, nys, nyn, nxl, nxr, nbgp )
	963	CALL exchange_horiz_2d_int( nzb_s_outer, nys, nyn, nxl, nxr, nbgp )
	964
	965	!
	966	!-- Set the individual index arrays which define the k index from which on
	967	!-- the usual finite difference form (which does not use surface fluxes) is
	968	!-- applied
	969	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
	970	nzb_diff_s_inner = nzb_s_inner + 2
	971	nzb_diff_s_outer = nzb_s_outer + 2
	972	ELSE
	973	nzb_diff_s_inner = nzb_s_inner + 1
	974	nzb_diff_s_outer = nzb_s_outer + 1
	975	ENDIF
	976	!
	977	!-- Vertical nesting: communicate vertical grid level arrays between fine and
	978	!-- coarse grid
	979	IF ( vnested ) CALL vnest_init_grid
	980
	981	END SUBROUTINE init_grid
	982
[3065]	983
[2696]	984	! Description:
	985	! -----------------------------------------------------------------------------!
[3065]	986	!> Calculation of the stretching factor through an iterative method. Ideas were
	987	!> taken from the paper "Regional stretched grid generation and its application
	988	!> to the NCAR RegCM (1999)". Normally, no analytic solution exists because the
	989	!> system of equations has two variables (r,l) but four requirements
	990	!> (l=integer, r=[0,88;1,2], Eq(6), Eq(5) starting from index j=1) which
	991	!> results into an overdetermined system.
	992	!------------------------------------------------------------------------------!
	993	SUBROUTINE calculate_stretching_factor( number_end )
	994
	995	USE control_parameters, &
[3241]	996	ONLY: dz, dz_stretch_factor_array, &
[3065]	997	dz_stretch_level_end, dz_stretch_level_start, message_string
	998
	999	USE kinds
	1000
	1001	IMPLICIT NONE
	1002
	1003	INTEGER(iwp) :: iterations !< number of iterations until stretch_factor_lower/upper_limit is reached
	1004	INTEGER(iwp) :: l_rounded !< after l_rounded grid levels dz(n) is strechted to dz(n+1) with stretch_factor_2
	1005	INTEGER(iwp) :: n !< loop variable for stretching
	1006
	1007	INTEGER(iwp), INTENT(IN) :: number_end !< number of user-specified end levels for stretching
	1008
	1009	REAL(wp) :: delta_l !< absolute difference between l and l_rounded
	1010	REAL(wp) :: delta_stretch_factor !< absolute difference between stretch_factor_1 and stretch_factor_2
	1011	REAL(wp) :: delta_total_new !< sum of delta_l and delta_stretch_factor for the next iteration (should be as small as possible)
	1012	REAL(wp) :: delta_total_old !< sum of delta_l and delta_stretch_factor for the last iteration
	1013	REAL(wp) :: distance !< distance between dz_stretch_level_start and dz_stretch_level_end (stretching region)
	1014	REAL(wp) :: l !< value that fulfil Eq. (5) in the paper mentioned above together with stretch_factor_1 exactly
	1015	REAL(wp) :: numerator !< numerator of the quotient
	1016	REAL(wp) :: stretch_factor_1 !< stretching factor that fulfil Eq. (5) togehter with l exactly
	1017	REAL(wp) :: stretch_factor_2 !< stretching factor that fulfil Eq. (6) togehter with l_rounded exactly
	1018
[3068]	1019	REAL(wp) :: dz_stretch_factor_array_2(9) = 1.08_wp !< Array that contains all stretch_factor_2 that belongs to stretch_factor_1
	1020
[4386]	1021	REAL(wp), PARAMETER :: stretch_factor_interval = 1.0E-06_wp !< interval for sampling possible stretching factors
	1022	REAL(wp), PARAMETER :: stretch_factor_lower_limit = 0.88_wp !< lowest possible stretching factor
	1023	REAL(wp), PARAMETER :: stretch_factor_upper_limit = 1.12_wp !< highest possible stretching factor
[3065]	1024
	1025
[3068]	1026	l = 0
	1027	DO n = 1, number_end
	1028
	1029	iterations = 1
[4386]	1030	stretch_factor_1 = 1.0_wp
	1031	stretch_factor_2 = 1.0_wp
	1032	delta_total_old = 1.0_wp
[3065]	1033
[4386]	1034	!
	1035	!-- First branch for stretching from rough to fine
[3068]	1036	IF ( dz(n) > dz(n+1) ) THEN
	1037	DO WHILE ( stretch_factor_1 >= stretch_factor_lower_limit )
	1038
[4386]	1039	stretch_factor_1 = 1.0_wp - iterations * stretch_factor_interval
	1040	distance = ABS( dz_stretch_level_end(n) - &
	1041	dz_stretch_level_start(n) )
	1042	numerator = distance*stretch_factor_1/dz(n) + &
[3068]	1043	stretch_factor_1 - distance/dz(n)
	1044
[4386]	1045	IF ( numerator > 0.0_wp ) THEN
	1046	l = LOG( numerator ) / LOG( stretch_factor_1 ) - 1.0_wp
[3068]	1047	l_rounded = NINT( l )
	1048	delta_l = ABS( l_rounded - l ) / l
	1049	ENDIF
	1050
	1051	stretch_factor_2 = EXP( LOG( dz(n+1)/dz(n) ) / (l_rounded) )
	1052
[4386]	1053	delta_stretch_factor = ABS( stretch_factor_1 - &
	1054	stretch_factor_2 ) / &
[3068]	1055	stretch_factor_2
	1056
	1057	delta_total_new = delta_l + delta_stretch_factor
[3065]	1058
	1059	!
[4386]	1060	!-- stretch_factor_1 is taken to guarantee that the stretching
	1061	!-- procedure ends as close as possible to dz_stretch_level_end.
	1062	!-- stretch_factor_2 would guarantee that the stretched dz(n) is
	1063	!-- equal to dz(n+1) after l_rounded grid levels.
[3068]	1064	IF (delta_total_new < delta_total_old) THEN
	1065	dz_stretch_factor_array(n) = stretch_factor_1
	1066	dz_stretch_factor_array_2(n) = stretch_factor_2
	1067	delta_total_old = delta_total_new
	1068	ENDIF
	1069
	1070	iterations = iterations + 1
	1071
	1072	ENDDO
[4386]	1073
	1074	!
	1075	!-- Second branch for stretching from fine to rough
[3068]	1076	ELSEIF ( dz(n) < dz(n+1) ) THEN
	1077	DO WHILE ( stretch_factor_1 <= stretch_factor_upper_limit )
	1078
[4386]	1079	stretch_factor_1 = 1.0_wp + iterations * stretch_factor_interval
	1080	distance = ABS( dz_stretch_level_end(n) - &
[3068]	1081	dz_stretch_level_start(n) )
[4386]	1082	numerator = distance*stretch_factor_1/dz(n) + &
[3068]	1083	stretch_factor_1 - distance/dz(n)
	1084
[4386]	1085	l = LOG( numerator ) / LOG( stretch_factor_1 ) - 1.0_wp
[3068]	1086	l_rounded = NINT( l )
	1087	delta_l = ABS( l_rounded - l ) / l
	1088
	1089	stretch_factor_2 = EXP( LOG( dz(n+1)/dz(n) ) / (l_rounded) )
[3065]	1090
[4386]	1091	delta_stretch_factor = ABS( stretch_factor_1 - &
	1092	stretch_factor_2 ) / &
[3068]	1093	stretch_factor_2
	1094
	1095	delta_total_new = delta_l + delta_stretch_factor
	1096
[3065]	1097	!
[4386]	1098	!-- stretch_factor_1 is taken to guarantee that the stretching
	1099	!-- procedure ends as close as possible to dz_stretch_level_end.
	1100	!-- stretch_factor_2 would guarantee that the stretched dz(n) is
	1101	!-- equal to dz(n+1) after l_rounded grid levels.
[3068]	1102	IF (delta_total_new < delta_total_old) THEN
	1103	dz_stretch_factor_array(n) = stretch_factor_1
	1104	dz_stretch_factor_array_2(n) = stretch_factor_2
	1105	delta_total_old = delta_total_new
	1106	ENDIF
[3065]	1107
[3068]	1108	iterations = iterations + 1
	1109	ENDDO
	1110
	1111	ELSE
	1112	message_string= 'Two adjacent values of dz must be different'
	1113	CALL message( 'init_grid', 'PA0228', 1, 2, 0, 6, 0 )
	1114
	1115	ENDIF
	1116
	1117	!
	1118	!-- Check if also the second stretching factor fits into the allowed
	1119	!-- interval. If not, print a warning for the user.
	1120	IF ( dz_stretch_factor_array_2(n) < stretch_factor_lower_limit .OR. &
	1121	dz_stretch_factor_array_2(n) > stretch_factor_upper_limit ) THEN
	1122	WRITE( message_string, * ) 'stretch_factor_2 = ', &
	1123	dz_stretch_factor_array_2(n), ' which is',&
	1124	' responsible for exactly reaching& dz =',&
	1125	dz(n+1), 'after a specific amount of', &
	1126	' grid levels& exceeds the upper', &
	1127	' limit =', stretch_factor_upper_limit, &
	1128	' &or lower limit = ', &
	1129	stretch_factor_lower_limit
	1130	CALL message( 'init_grid', 'PA0499', 0, 1, 0, 6, 0 )
	1131
	1132	ENDIF
	1133	ENDDO
[3065]	1134
	1135	END SUBROUTINE calculate_stretching_factor
	1136
	1137
	1138	! Description:
	1139	! -----------------------------------------------------------------------------!
[2696]	1140	!> Set temporary topography flags and reference buildings on top of underlying
	1141	!> orography.
	1142	!------------------------------------------------------------------------------!
	1143	SUBROUTINE process_topography( topo_3d )
	1144
	1145	USE arrays_3d, &
[2747]	1146	ONLY: zu, zw
[2696]	1147
	1148	USE control_parameters, &
[3294]	1149	ONLY: bc_lr_cyc, bc_ns_cyc, message_string, ocean_mode
[2696]	1150
	1151	USE indices, &
	1152	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, &
	1153	nzt
	1154
	1155	USE netcdf_data_input_mod, &
[3115]	1156	ONLY: buildings_f, building_id_f, building_type_f, input_pids_static, &
[2696]	1157	terrain_height_f
	1158
	1159	USE kinds
	1160
	1161	USE pegrid
	1162
	1163	IMPLICIT NONE
	1164
[2867]	1165	INTEGER(iwp) :: i !< running index along x-direction
	1166	INTEGER(iwp) :: j !< running index along y-direction
	1167	INTEGER(iwp) :: k !< running index along z-direction with respect to numeric grid
	1168	INTEGER(iwp) :: k2 !< running index along z-direction with respect to netcdf grid
	1169	INTEGER(iwp) :: nr !< index variable indication maximum terrain height for respective building ID
	1170	INTEGER(iwp) :: num_build !< counter for number of buildings
	1171	INTEGER(iwp) :: topo_top_index !< orography top index, used to map 3D buildings onto terrain
[2696]	1172
	1173	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: displace_dum !< displacements of start addresses, used for MPI_ALLGATHERV
	1174	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids !< building IDs on entire model domain
	1175	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_final !< building IDs on entire model domain, multiple occurences are sorted out
	1176	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_final_tmp !< temporary array used for resizing
	1177	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_l !< building IDs on local subdomain
	1178	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_l_tmp !< temporary array used to resize array of building IDs
	1179
	1180	INTEGER(iwp), DIMENSION(0:numprocs-1) :: num_buildings !< number of buildings with different ID on entire model domain
	1181	INTEGER(iwp), DIMENSION(0:numprocs-1) :: num_buildings_l !< number of buildings with different ID on local subdomain
	1182
	1183	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo_3d !< input array for 3D topography and dummy array for setting "outer"-flags
	1184
	1185	REAL(wp) :: ocean_offset !< offset to consider inverse vertical coordinate at topography definition
[3103]	1186	REAL(wp) :: oro_min = 0.0_wp !< minimum terrain height in entire model domain, used to reference terrain to zero
[2696]	1187	REAL(wp), DIMENSION(:), ALLOCATABLE :: oro_max !< maximum terrain height occupied by an building with certain id
	1188	REAL(wp), DIMENSION(:), ALLOCATABLE :: oro_max_l !< maximum terrain height occupied by an building with certain id, on local subdomain
	1189
	1190	!
[3103]	1191	!-- Reference lowest terrain height to zero. In case the minimum terrain height
	1192	!-- is non-zero, all grid points of the lower vertical grid levels might be
	1193	!-- entirely below the surface, meaning a waste of computational resources.
	1194	!-- In order to avoid this, remove the lowest terrain height. Please note,
	1195	!-- in case of a nested run, the global minimum from all parent and childs
	1196	!-- need to be remove to avoid steep edges at the child-domain boundaries.
	1197	IF ( input_pids_static ) THEN
[4159]	1198
[3200]	1199	#if defined( __parallel )
[3103]	1200	CALL MPI_ALLREDUCE( MINVAL( terrain_height_f%var ), oro_min, 1, &
	1201	MPI_REAL, MPI_MIN, MPI_COMM_WORLD, ierr )
[3200]	1202	#else
	1203	oro_min = MINVAL( terrain_height_f%var )
	1204	#endif
[3103]	1205	terrain_height_f%var = terrain_height_f%var - oro_min
	1206	!
	1207	!-- Give an informative message that terrain height is referenced to zero
	1208	IF ( oro_min > 0.0_wp ) THEN
	1209	WRITE( message_string, * ) 'Terrain height was internally shifted '//&
	1210	'downwards by ', oro_min, 'meter(s) to save ' // &
	1211	'computational resources.'
	1212	CALL message( 'init_grid', 'PA0505', 0, 0, 0, 6, 0 )
	1213	ENDIF
	1214	ENDIF
	1215
	1216	!
[2696]	1217	!-- In the following, buildings and orography are further preprocessed
	1218	!-- before they are mapped on the LES grid.
	1219	!-- Buildings are mapped on top of the orography by maintaining the roof
	1220	!-- shape of the building. This can be achieved by referencing building on
	1221	!-- top of the maximum terrain height within the area occupied by the
	1222	!-- respective building. As buildings and terrain height are defined PE-wise,
	1223	!-- parallelization of this referencing is required (a building can be
	1224	!-- distributed between different PEs).
	1225	!-- In a first step, determine the number of buildings with different
	1226	!-- building id on each PE. In a next step, all building ids are gathered
	1227	!-- into one array which is present to all PEs. For each building ID,
	1228	!-- the maximum terrain height occupied by the respective building is
	1229	!-- computed and distributed to each PE.
	1230	!-- Finally, for each building id and its respective reference orography,
	1231	!-- builidings are mapped on top.
	1232	!--
	1233	!-- First, pre-set topography flags, bit 1 indicates orography, bit 2
	1234	!-- buildings
	1235	!-- classify the respective surfaces.
	1236	topo_3d = IBSET( topo_3d, 0 )
	1237	topo_3d(nzb,:,:) = IBCLR( topo_3d(nzb,:,:), 0 )
	1238	!
[3051]	1239	!-- In order to map topography on PALM grid also in case of ocean simulations,
	1240	!-- pre-calculate an offset value.
[3294]	1241	ocean_offset = MERGE( zw(0), 0.0_wp, ocean_mode )
[3051]	1242	!
[2696]	1243	!-- Reference buildings on top of orography. This is not necessary
	1244	!-- if topography is read from ASCII file as no distinction between buildings
	1245	!-- and terrain height can be made. Moreover, this is also not necessary if
	1246	!-- urban-surface and land-surface model are used at the same time.
[2897]	1247	IF ( input_pids_static ) THEN
	1248
	1249	IF ( buildings_f%from_file ) THEN
	1250	num_buildings_l = 0
	1251	num_buildings = 0
[2696]	1252	!
[3925]	1253	!-- Allocate at least one element for building ids and give it an inital
	1254	!-- negative value that will be overwritten later. This, however, is
	1255	!-- necessary in case there all IDs in the model domain are fill values.
[2897]	1256	ALLOCATE( build_ids_l(1) )
[3925]	1257	build_ids_l = -1
[2897]	1258	DO i = nxl, nxr
	1259	DO j = nys, nyn
	1260	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1261	IF ( num_buildings_l(myid) > 0 ) THEN
[4144]	1262	IF ( ANY( building_id_f%var(j,i) == build_ids_l ) ) &
[2897]	1263	THEN
	1264	CYCLE
	1265	ELSE
	1266	num_buildings_l(myid) = num_buildings_l(myid) + 1
[2696]	1267	!
	1268	!-- Resize array with different local building ids
	1269	ALLOCATE( build_ids_l_tmp(1:SIZE(build_ids_l)) )
	1270	build_ids_l_tmp = build_ids_l
	1271	DEALLOCATE( build_ids_l )
	1272	ALLOCATE( build_ids_l(1:num_buildings_l(myid)) )
	1273	build_ids_l(1:num_buildings_l(myid)-1) = &
	1274	build_ids_l_tmp(1:num_buildings_l(myid)-1)
	1275	build_ids_l(num_buildings_l(myid)) = building_id_f%var(j,i)
	1276	DEALLOCATE( build_ids_l_tmp )
	1277	ENDIF
	1278	!
[2897]	1279	!-- First occuring building id on PE
	1280	ELSE
	1281	num_buildings_l(myid) = num_buildings_l(myid) + 1
	1282	build_ids_l(1) = building_id_f%var(j,i)
	1283	ENDIF
[2696]	1284	ENDIF
[2897]	1285	ENDDO
[2696]	1286	ENDDO
	1287	!
[2897]	1288	!-- Determine number of different building ids for the entire domain
[2696]	1289	#if defined( __parallel )
[2897]	1290	CALL MPI_ALLREDUCE( num_buildings_l, num_buildings, numprocs, &
	1291	MPI_INTEGER, MPI_SUM, comm2d, ierr )
[2696]	1292	#else
[2897]	1293	num_buildings = num_buildings_l
[2696]	1294	#endif
	1295	!
[2897]	1296	!-- Gather all buildings ids on each PEs.
	1297	!-- First, allocate array encompassing all building ids in model domain.
	1298	ALLOCATE( build_ids(1:SUM(num_buildings)) )
[2696]	1299	#if defined( __parallel )
	1300	!
[2897]	1301	!-- Allocate array for displacements.
	1302	!-- As each PE may has a different number of buildings, so that
	1303	!-- the block sizes send by each PE may not be equal. Hence,
	1304	!-- information about the respective displacement is required, indicating
	1305	!-- the respective adress where each MPI-task writes into the receive
	1306	!-- buffer array
	1307	ALLOCATE( displace_dum(0:numprocs-1) )
	1308	displace_dum(0) = 0
	1309	DO i = 1, numprocs-1
	1310	displace_dum(i) = displace_dum(i-1) + num_buildings(i-1)
	1311	ENDDO
[2696]	1312
[2897]	1313	CALL MPI_ALLGATHERV( build_ids_l(1:num_buildings_l(myid)), &
	1314	num_buildings(myid), &
	1315	MPI_INTEGER, &
	1316	build_ids, &
	1317	num_buildings, &
	1318	displace_dum, &
	1319	MPI_INTEGER, &
	1320	comm2d, ierr )
[2696]	1321
[2897]	1322	DEALLOCATE( displace_dum )
[2696]	1323
	1324	#else
[2897]	1325	build_ids = build_ids_l
[2696]	1326	#endif
	1327
	1328	!
[2897]	1329	!-- Note, in parallel mode building ids can occure mutliple times, as
	1330	!-- each PE has send its own ids. Therefore, sort out building ids which
	1331	!-- appear more than one time.
	1332	num_build = 0
	1333	DO nr = 1, SIZE(build_ids)
[2696]	1334
[2897]	1335	IF ( ALLOCATED(build_ids_final) ) THEN
[4144]	1336	IF ( ANY( build_ids(nr) == build_ids_final ) ) THEN
[2897]	1337	CYCLE
	1338	ELSE
	1339	num_build = num_build + 1
	1340	!
	1341	!-- Resize
	1342	ALLOCATE( build_ids_final_tmp(1:num_build) )
	1343	build_ids_final_tmp(1:num_build-1) = build_ids_final(1:num_build-1)
	1344	DEALLOCATE( build_ids_final )
	1345	ALLOCATE( build_ids_final(1:num_build) )
	1346	build_ids_final(1:num_build-1) = build_ids_final_tmp(1:num_build-1)
	1347	build_ids_final(num_build) = build_ids(nr)
	1348	DEALLOCATE( build_ids_final_tmp )
	1349	ENDIF
[2696]	1350	ELSE
	1351	num_build = num_build + 1
	1352	ALLOCATE( build_ids_final(1:num_build) )
	1353	build_ids_final(num_build) = build_ids(nr)
[2897]	1354	ENDIF
	1355	ENDDO
[2696]	1356
	1357	!
[3051]	1358	!-- Determine maximumum terrain height occupied by the respective
	1359	!-- building and temporalily store on oro_max
[2897]	1360	ALLOCATE( oro_max_l(1:SIZE(build_ids_final)) )
	1361	ALLOCATE( oro_max(1:SIZE(build_ids_final)) )
	1362	oro_max_l = 0.0_wp
[2696]	1363
[2897]	1364	DO nr = 1, SIZE(build_ids_final)
[4159]	1365	oro_max_l(nr) = MAXVAL( &
	1366	MERGE( terrain_height_f%var(nys:nyn,nxl:nxr), &
	1367	0.0_wp, &
	1368	building_id_f%var(nys:nyn,nxl:nxr) == &
[2897]	1369	build_ids_final(nr) ) )
	1370	ENDDO
[2696]	1371
	1372	#if defined( __parallel )
[2897]	1373	IF ( SIZE(build_ids_final) >= 1 ) THEN
[4159]	1374	CALL MPI_ALLREDUCE( oro_max_l, oro_max, SIZE( oro_max ), MPI_REAL,&
[2897]	1375	MPI_MAX, comm2d, ierr )
	1376	ENDIF
[2696]	1377	#else
[2897]	1378	oro_max = oro_max_l
[2696]	1379	#endif
[3051]	1380	!
	1381	!-- Finally, determine discrete grid height of maximum orography occupied
[4159]	1382	!-- by a building. Use all-or-nothing approach, i.e. if terrain
	1383	!-- exceeds the scalar level the grid box is fully terrain and the
	1384	!-- maximum terrain is set to the zw level.
	1385	!-- terrain or
[3051]	1386	oro_max_l = 0.0
	1387	DO nr = 1, SIZE(build_ids_final)
	1388	DO k = nzb, nzt
	1389	IF ( zu(k) - ocean_offset <= oro_max(nr) ) &
[3142]	1390	oro_max_l(nr) = zw(k) - ocean_offset
[3051]	1391	ENDDO
[3142]	1392	oro_max(nr) = oro_max_l(nr)
[3051]	1393	ENDDO
[2897]	1394	ENDIF
[2696]	1395	!
[4245]	1396	!-- Allocate array for storing terrain height under buildings
	1397	IF ( buildings_f%from_file ) THEN
	1398	ALLOCATE( buildings_f%oro_max(nysg:nyng,nxlg:nxrg) )
	1399	buildings_f%oro_max = buildings_f%fill1
	1400	END IF
	1401	!
[2867]	1402	!-- Map orography as well as buildings onto grid.
[2696]	1403	DO i = nxl, nxr
	1404	DO j = nys, nyn
[2867]	1405	topo_top_index = 0
[3142]	1406	!
	1407	!-- Obtain index in global building_id array
	1408	IF ( buildings_f%from_file ) THEN
	1409	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1410	!
	1411	!-- Determine index where maximum terrain height occupied by
	1412	!-- the respective building height is stored.
	1413	nr = MINLOC( ABS( build_ids_final - &
	1414	building_id_f%var(j,i) ), DIM = 1 )
[4245]	1415	!
	1416	!-- Save grid-indexed oro_max
	1417	buildings_f%oro_max(j,i) = oro_max(nr)
[3142]	1418	ENDIF
	1419	ENDIF
[2696]	1420	DO k = nzb, nzt
	1421	!
	1422	!-- In a first step, if grid point is below or equal the given
	1423	!-- terrain height, grid point is flagged to be of type natural.
	1424	!-- Please note, in case there is also a building which is lower
	1425	!-- than the vertical grid spacing, initialization of surface
	1426	!-- attributes will not be correct as given surface information
	1427	!-- will not be in accordance to the classified grid points.
[4159]	1428	!-- Hence, in this case, also a building flag.
[2747]	1429	IF ( zu(k) - ocean_offset <= terrain_height_f%var(j,i) ) THEN
[4189]	1430	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
	1431	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1432	topo_top_index = k ! topo_top_index + 1
[2696]	1433	ENDIF
	1434	!
	1435	!-- Set building grid points. Here, only consider 2D buildings.
	1436	!-- 3D buildings require separate treatment.
[2897]	1437	IF ( buildings_f%from_file .AND. buildings_f%lod == 1 ) THEN
[4159]	1438	!
	1439	!-- Fill-up the terrain to the level of maximum orography
	1440	!-- within the building-covered area.
	1441	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1442	!
	1443	!-- Note, oro_max is always on zw level
	1444	IF ( zu(k) - ocean_offset < oro_max(nr) ) THEN
[2696]	1445	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4159]	1446	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1447	ELSEIF ( zu(k) - ocean_offset <= &
	1448	oro_max(nr) + buildings_f%var_2d(j,i) ) THEN
	1449	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[2696]	1450	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1451	ENDIF
	1452	ENDIF
	1453	ENDIF
	1454	ENDDO
	1455	!
[4159]	1456	!-- Special treatment for non grid-resolved buildings. This case,
	1457	!-- the uppermost terrain grid point is flagged as building as well
	1458	!-- well, even though no building exists at all. However, the
	1459	!-- surface element will be identified as urban-surface and the
	1460	!-- input data provided by the drivers is consistent to the surface
	1461	!-- classification. Else, all non grid-resolved buildings would vanish
	1462	!-- and identified as terrain grid points, which, however, won't be
	1463	!-- consistent with the input data.
	1464	IF ( buildings_f%from_file .AND. buildings_f%lod == 1 ) THEN
	1465	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1466	DO k = nzb, nzt
	1467	IF( zw(k) - ocean_offset == oro_max(nr) ) THEN
	1468	IF ( buildings_f%var_2d(j,i) <= zu(k+1) - zw(k) ) THEN
	1469	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1470	ENDIF
	1471	ENDIF
	1472	ENDDO
	1473	ENDIF
	1474	ENDIF
	1475	!
[2696]	1476	!-- Map 3D buildings onto terrain height.
[2867]	1477	!-- In case of any slopes, map building on top of maximum terrain
	1478	!-- height covered by the building. In other words, extend
	1479	!-- building down to the respective local terrain-surface height.
[2897]	1480	IF ( buildings_f%from_file .AND. buildings_f%lod == 2 ) THEN
[2696]	1481	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1482	!
[3051]	1483	!-- Extend building down to the terrain surface, i.e. fill-up
	1484	!-- surface irregularities below a building. Note, oro_max
	1485	!-- is already a discrete height according to the all-or-nothing
	1486	!-- approach, i.e. grid box is either topography or atmosphere,
	1487	!-- terrain top is defined at upper bound of the grid box.
	1488	!-- Hence, check for zw in this case.
[3115]	1489	!-- Note, do this only for buildings which are surface mounted,
	1490	!-- i.e. building types 1-6. Below bridges, which are represented
	1491	!-- exclusively by building type 7, terrain shape should be
	1492	!-- maintained.
[3855]	1493	IF ( building_type_f%from_file ) THEN
	1494	IF ( building_type_f%var(j,i) /= 7 ) THEN
	1495	DO k = topo_top_index + 1, nzt + 1
[4159]	1496	IF ( zu(k) - ocean_offset <= oro_max(nr) ) THEN
[3855]	1497	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4159]	1498	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
[3855]	1499	ENDIF
	1500	ENDDO
	1501	!
	1502	!-- After surface irregularities are smoothen, determine
	1503	!-- lower start index where building starts.
	1504	DO k = nzb, nzt
[4159]	1505	IF ( zu(k) - ocean_offset <= oro_max(nr) ) &
[3855]	1506	topo_top_index = k
	1507	ENDDO
	1508	ENDIF
[3115]	1509	ENDIF
[3051]	1510	!
	1511	!-- Finally, map building on top.
[2867]	1512	k2 = 0
	1513	DO k = topo_top_index, nzt + 1
[2796]	1514	IF ( k2 <= buildings_f%nz-1 ) THEN
[2696]	1515	IF ( buildings_f%var_3d(k2,j,i) == 1 ) THEN
	1516	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
	1517	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1518	ENDIF
	1519	ENDIF
	1520	k2 = k2 + 1
	1521	ENDDO
	1522	ENDIF
	1523	ENDIF
	1524	ENDDO
	1525	ENDDO
	1526	!
[4265]	1527	!-- Horizontal exchange the oro_max array, which is required to for
	1528	!-- initialization of building-surface properties.
	1529	IF ( ALLOCATED( buildings_f%oro_max ) ) THEN
	1530	CALL exchange_horiz_2d( buildings_f%oro_max(:,:), nbgp )
	1531	ENDIF
[4245]	1532	!
[2696]	1533	!-- Deallocate temporary arrays required for processing and reading data
	1534	IF ( ALLOCATED( oro_max ) ) DEALLOCATE( oro_max )
	1535	IF ( ALLOCATED( oro_max_l ) ) DEALLOCATE( oro_max_l )
	1536	IF ( ALLOCATED( build_ids_final ) ) DEALLOCATE( build_ids_final )
	1537	!
	1538	!-- Topography input via ASCII format.
	1539	ELSE
[3294]	1540	ocean_offset = MERGE( zw(0), 0.0_wp, ocean_mode )
[4159]	1541	!
	1542	!-- Initialize topography bit 0 (indicates obstacle) everywhere to zero
	1543	!-- and clear all grid points at nzb, where alway a surface is defined.
	1544	!-- Further, set also bit 1 (indicates terrain) at nzb, which is further
	1545	!-- used for masked data output and further processing. Note, in the
	1546	!-- ASCII case no distinction is made between buildings and terrain,
	1547	!-- so that setting of bit 1 and 2 at the same time has no effect.
[2696]	1548	topo_3d = IBSET( topo_3d, 0 )
	1549	topo_3d(nzb,:,:) = IBCLR( topo_3d(nzb,:,:), 0 )
[4159]	1550	topo_3d(nzb,:,:) = IBSET( topo_3d(nzb,:,:), 1 )
[2696]	1551	DO i = nxl, nxr
	1552	DO j = nys, nyn
	1553	DO k = nzb, nzt
[3538]	1554	!
	1555	!-- Flag topography for all grid points which are below
	1556	!-- the local topography height.
	1557	!-- Note, each topography is flagged as building.
[2747]	1558	IF ( zu(k) - ocean_offset <= buildings_f%var_2d(j,i) ) THEN
[4189]	1559	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
	1560	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 ) !indicates building
[2696]	1561	ENDIF
	1562	ENDDO
	1563	ENDDO
	1564	ENDDO
	1565	ENDIF
	1566
	1567	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
	1568
	1569	IF ( .NOT. bc_ns_cyc ) THEN
	1570	IF ( nys == 0 ) topo_3d(:,-1,:) = topo_3d(:,0,:)
	1571	IF ( nyn == ny ) topo_3d(:,ny+1,:) = topo_3d(:,ny,:)
	1572	ENDIF
	1573
	1574	IF ( .NOT. bc_lr_cyc ) THEN
	1575	IF ( nxl == 0 ) topo_3d(:,:,-1) = topo_3d(:,:,0)
	1576	IF ( nxr == nx ) topo_3d(:,:,nx+1) = topo_3d(:,:,nx)
	1577	ENDIF
	1578
	1579	END SUBROUTINE process_topography
	1580
	1581
	1582	! Description:
	1583	! -----------------------------------------------------------------------------!
	1584	!> Filter topography, i.e. fill holes resolved by only one grid point.
	1585	!> Such holes are suspected to lead to velocity blow-ups as continuity
	1586	!> equation on discrete grid cannot be fulfilled in such case.
	1587	!------------------------------------------------------------------------------!
	1588	SUBROUTINE filter_topography( topo_3d )
	1589
	1590	USE control_parameters, &
	1591	ONLY: bc_lr_cyc, bc_ns_cyc, message_string
	1592
	1593	USE indices, &
	1594	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, nzt
	1595
	1596	USE netcdf_data_input_mod, &
	1597	ONLY: building_id_f, building_type_f
	1598
	1599	USE pegrid
	1600
	1601	IMPLICIT NONE
	1602
[2893]	1603	LOGICAL :: filled = .FALSE. !< flag indicating if holes were filled
	1604
[2696]	1605	INTEGER(iwp) :: i !< running index along x-direction
	1606	INTEGER(iwp) :: j !< running index along y-direction
	1607	INTEGER(iwp) :: k !< running index along z-direction
	1608	INTEGER(iwp) :: num_hole !< number of holes (in topography) resolved by only one grid point
	1609	INTEGER(iwp) :: num_hole_l !< number of holes (in topography) resolved by only one grid point on local PE
	1610	INTEGER(iwp) :: num_wall !< number of surrounding vertical walls for a single grid point
	1611
[2955]	1612	INTEGER(iwp), DIMENSION(:,:,:), ALLOCATABLE :: topo_tmp !< temporary 3D-topography used to fill holes
	1613	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo_3d !< 3D-topography array merging buildings and orography
[2696]	1614	!
	1615	!-- Before checking for holes, set lateral boundary conditions for
	1616	!-- topography. After hole-filling, boundary conditions must be set again.
	1617	!-- Several iterations are performed, in order to fill holes which might
	1618	!-- emerge by the filling-algorithm itself.
	1619	ALLOCATE( topo_tmp(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	1620	topo_tmp = 0
	1621
	1622	num_hole = 99999
	1623	DO WHILE ( num_hole > 0 )
	1624
	1625	num_hole = 0
	1626	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
[2955]	1627	!
	1628	!-- Exchange also building ID and type. Note, building_type is an one-byte
	1629	!-- variable.
	1630	IF ( building_id_f%from_file ) &
	1631	CALL exchange_horiz_2d_int( building_id_f%var, nys, nyn, nxl, nxr, nbgp )
[3763]	1632	IF ( building_type_f%from_file ) &
	1633	CALL exchange_horiz_2d_byte( building_type_f%var, nys, nyn, nxl, nxr, nbgp )
[2696]	1634
	1635	topo_tmp = topo_3d
	1636	!
	1637	!-- In case of non-cyclic lateral boundaries, assume lateral boundary to be
	1638	!-- a solid wall. Thus, intermediate spaces of one grid point between
	1639	!-- boundary and some topographic structure will be filled.
	1640	IF ( .NOT. bc_ns_cyc ) THEN
	1641	IF ( nys == 0 ) topo_tmp(:,-1,:) = IBCLR( topo_tmp(:,0,:), 0 )
	1642	IF ( nyn == ny ) topo_tmp(:,ny+1,:) = IBCLR( topo_tmp(:,ny,:), 0 )
	1643	ENDIF
	1644
	1645	IF ( .NOT. bc_lr_cyc ) THEN
	1646	IF ( nxl == 0 ) topo_tmp(:,:,-1) = IBCLR( topo_tmp(:,:,0), 0 )
	1647	IF ( nxr == nx ) topo_tmp(:,:,nx+1) = IBCLR( topo_tmp(:,:,nx), 0 )
	1648	ENDIF
	1649
	1650	num_hole_l = 0
	1651	DO i = nxl, nxr
	1652	DO j = nys, nyn
	1653	DO k = nzb+1, nzt
	1654	IF ( BTEST( topo_tmp(k,j,i), 0 ) ) THEN
	1655	num_wall = 0
	1656	IF ( .NOT. BTEST( topo_tmp(k,j-1,i), 0 ) ) &
	1657	num_wall = num_wall + 1
	1658	IF ( .NOT. BTEST( topo_tmp(k,j+1,i), 0 ) ) &
	1659	num_wall = num_wall + 1
	1660	IF ( .NOT. BTEST( topo_tmp(k,j,i-1), 0 ) ) &
	1661	num_wall = num_wall + 1
	1662	IF ( .NOT. BTEST( topo_tmp(k,j,i+1), 0 ) ) &
	1663	num_wall = num_wall + 1
	1664	IF ( .NOT. BTEST( topo_tmp(k-1,j,i), 0 ) ) &
	1665	num_wall = num_wall + 1
	1666	IF ( .NOT. BTEST( topo_tmp(k+1,j,i), 0 ) ) &
	1667	num_wall = num_wall + 1
	1668
	1669	IF ( num_wall >= 4 ) THEN
	1670	num_hole_l = num_hole_l + 1
	1671	!
[4314]	1672	!-- Clear flag 0 and set special flag ( bit 4) to indicate
[2696]	1673	!-- that new topography point is a result of filtering process.
	1674	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4314]	1675	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 4 )
[2696]	1676	!
	1677	!-- If filled grid point is occupied by a building, classify
	1678	!-- it as building grid point.
	1679	IF ( building_type_f%from_file ) THEN
	1680	IF ( building_type_f%var(j,i) /= &
	1681	building_type_f%fill .OR. &
	1682	building_type_f%var(j+1,i) /= &
	1683	building_type_f%fill .OR. &
	1684	building_type_f%var(j-1,i) /= &
	1685	building_type_f%fill .OR. &
	1686	building_type_f%var(j,i+1) /= &
	1687	building_type_f%fill .OR. &
	1688	building_type_f%var(j,i-1) /= &
	1689	building_type_f%fill ) THEN
	1690	!
	1691	!-- Set flag indicating building surfaces
	1692	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1693	!
	1694	!-- Set building_type and ID at this position if not
	1695	!-- already set. This is required for proper
	1696	!-- initialization of urban-surface energy balance
	1697	!-- solver.
	1698	IF ( building_type_f%var(j,i) == &
	1699	building_type_f%fill ) THEN
	1700
	1701	IF ( building_type_f%var(j+1,i) /= &
	1702	building_type_f%fill ) THEN
	1703	building_type_f%var(j,i) = &
	1704	building_type_f%var(j+1,i)
	1705	building_id_f%var(j,i) = &
	1706	building_id_f%var(j+1,i)
	1707	ELSEIF ( building_type_f%var(j-1,i) /= &
	1708	building_type_f%fill ) THEN
	1709	building_type_f%var(j,i) = &
	1710	building_type_f%var(j-1,i)
	1711	building_id_f%var(j,i) = &
	1712	building_id_f%var(j-1,i)
	1713	ELSEIF ( building_type_f%var(j,i+1) /= &
	1714	building_type_f%fill ) THEN
	1715	building_type_f%var(j,i) = &
	1716	building_type_f%var(j,i+1)
	1717	building_id_f%var(j,i) = &
	1718	building_id_f%var(j,i+1)
	1719	ELSEIF ( building_type_f%var(j,i-1) /= &
	1720	building_type_f%fill ) THEN
	1721	building_type_f%var(j,i) = &
	1722	building_type_f%var(j,i-1)
	1723	building_id_f%var(j,i) = &
	1724	building_id_f%var(j,i-1)
	1725	ENDIF
	1726	ENDIF
	1727	ENDIF
	1728	ENDIF
	1729	!
	1730	!-- If filled grid point is already classified as building
	1731	!-- everything is fine, else classify this grid point as
	1732	!-- natural type grid point. This case, values for the
	1733	!-- surface type are already set.
	1734	IF ( .NOT. BTEST( topo_3d(k,j,i), 2 ) ) THEN
	1735	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1736	ENDIF
	1737	ENDIF
	1738	ENDIF
	1739	ENDDO
	1740	ENDDO
	1741	ENDDO
	1742	!
	1743	!-- Count the total number of holes, required for informative message.
	1744	#if defined( __parallel )
	1745	CALL MPI_ALLREDUCE( num_hole_l, num_hole, 1, MPI_INTEGER, MPI_SUM, &
	1746	comm2d, ierr )
	1747	#else
	1748	num_hole = num_hole_l
	1749	#endif
[2893]	1750	IF ( num_hole > 0 .AND. .NOT. filled ) filled = .TRUE.
[2696]	1751
[2893]	1752	ENDDO
[2696]	1753	!
[2893]	1754	!-- Create an informative message if any holes were filled.
	1755	IF ( filled ) THEN
	1756	WRITE( message_string, * ) 'Topography was filtered, i.e. holes ' // &
	1757	'resolved by only one grid point ' // &
	1758	'were filled during initialization.'
	1759	CALL message( 'init_grid', 'PA0430', 0, 0, 0, 6, 0 )
	1760	ENDIF
[2696]	1761
	1762	DEALLOCATE( topo_tmp )
	1763	!
	1764	!-- Finally, exchange topo_3d array again and if necessary set Neumann boundary
	1765	!-- condition in case of non-cyclic lateral boundaries.
	1766	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
	1767
	1768	IF ( .NOT. bc_ns_cyc ) THEN
	1769	IF ( nys == 0 ) topo_3d(:,-1,:) = topo_3d(:,0,:)
	1770	IF ( nyn == ny ) topo_3d(:,ny+1,:) = topo_3d(:,ny,:)
	1771	ENDIF
	1772
	1773	IF ( .NOT. bc_lr_cyc ) THEN
	1774	IF ( nxl == 0 ) topo_3d(:,:,-1) = topo_3d(:,:,0)
	1775	IF ( nxr == nx ) topo_3d(:,:,nx+1) = topo_3d(:,:,nx)
	1776	ENDIF
[2955]	1777	!
	1778	!-- Exchange building ID and type. Note, building_type is an one-byte variable.
	1779	IF ( building_id_f%from_file ) &
	1780	CALL exchange_horiz_2d_int( building_id_f%var, nys, nyn, nxl, nxr, nbgp )
[3763]	1781	IF ( building_type_f%from_file ) &
	1782	CALL exchange_horiz_2d_byte( building_type_f%var, nys, nyn, nxl, nxr, nbgp )
[2696]	1783
	1784	END SUBROUTINE filter_topography
	1785
	1786
	1787	! Description:
	1788	! -----------------------------------------------------------------------------!
	1789	!> Reads topography information from file or sets generic topography. Moreover,
	1790	!> all topography-relevant topography arrays are initialized, and grid flags
	1791	!> are set.
	1792	!------------------------------------------------------------------------------!
	1793	SUBROUTINE init_topo( topo )
	1794
	1795	USE arrays_3d, &
	1796	ONLY: zw
	1797
	1798	USE control_parameters, &
	1799	ONLY: bc_lr_cyc, bc_ns_cyc, building_height, building_length_x, &
	1800	building_length_y, building_wall_left, building_wall_south, &
	1801	canyon_height, canyon_wall_left, canyon_wall_south, &
	1802	canyon_width_x, canyon_width_y, dp_level_ind_b, dz, &
[3241]	1803	message_string, topography, topography_grid_convention, &
[2696]	1804	tunnel_height, tunnel_length, tunnel_width_x, tunnel_width_y, &
	1805	tunnel_wall_depth
	1806
	1807	USE grid_variables, &
	1808	ONLY: dx, dy
	1809
	1810	USE indices, &
	1811	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
	1812	nzb, nzt
	1813
	1814	USE kinds
[4189]	1815
	1816	USE netcdf_data_input_mod, &
	1817	ONLY: buildings_f, terrain_height_f
[2696]	1818
	1819	USE pegrid
	1820
	1821	IMPLICIT NONE
	1822
[4386]	1823	INTEGER(iwp) :: bh !< temporary vertical index of building height
	1824	INTEGER(iwp) :: ngp_bx !< grid point number of building size along x
	1825	INTEGER(iwp) :: ngp_by !< grid point number of building size along y
	1826	INTEGER(iwp) :: index_left_bwall !< index for left building wall
	1827	INTEGER(iwp) :: index_right_bwall !< index for right building wall
	1828	INTEGER(iwp) :: index_north_bwall !< index for north building wall
	1829	INTEGER(iwp) :: index_south_bwall !< index for south building wall
	1830	INTEGER(iwp) :: ch !< temporary vertical index for canyon height
	1831	INTEGER(iwp) :: ngp_cx !< grid point number of canyon size along x
	1832	INTEGER(iwp) :: ngp_cy !< grid point number of canyon size along y
	1833	INTEGER(iwp) :: index_left_cwall !< index for left canyon wall
	1834	INTEGER(iwp) :: index_right_cwall !< index for right canyon wall
	1835	INTEGER(iwp) :: index_north_cwall !< index for north canyon wall
	1836	INTEGER(iwp) :: index_south_cwall !< index for south canyon wall
	1837	INTEGER(iwp) :: i !< index variable along x
	1838	INTEGER(iwp) :: j !< index variable along y
	1839	INTEGER(iwp) :: k !< index variable along z
	1840	INTEGER(iwp) :: hv_in !< heavyside function to model inner tunnel surface
	1841	INTEGER(iwp) :: hv_out !< heavyside function to model outer tunnel surface
	1842	INTEGER(iwp) :: txe_out !< end position of outer tunnel wall in x
	1843	INTEGER(iwp) :: txs_out !< start position of outer tunnel wall in x
	1844	INTEGER(iwp) :: tye_out !< end position of outer tunnel wall in y
	1845	INTEGER(iwp) :: tys_out !< start position of outer tunnel wall in y
	1846	INTEGER(iwp) :: txe_in !< end position of inner tunnel wall in x
	1847	INTEGER(iwp) :: txs_in !< start position of inner tunnel wall in x
	1848	INTEGER(iwp) :: tye_in !< end position of inner tunnel wall in y
	1849	INTEGER(iwp) :: tys_in !< start position of inner tunnel wall in y
	1850	INTEGER(iwp) :: td !< tunnel wall depth
	1851	INTEGER(iwp) :: th !< height of outer tunnel wall
[2696]	1852
	1853	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nzb_local !< index for topography top at cell-center
	1854	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo !< input array for 3D topography and dummy array for setting "outer"-flags
	1855	!
[4189]	1856	!-- Check for correct setting of the namelist parameter topography. If
	1857	!-- topography information is read from file but topography = 'flat',
[4386]	1858	!-- initialization does not work properly.
[4189]	1859	IF ( ( buildings_f%from_file .OR. terrain_height_f%from_file ) .AND. &
	1860	TRIM( topography ) /= 'read_from_file' ) THEN
	1861	message_string = 'If topography information is provided (via ' // &
	1862	'Netcdf or ASCII input) topography = ' // &
	1863	'"read_from_file" is required.'
	1864	CALL message( 'init_grid', 'PA0437', 1, 2, 0, 6, 0 )
	1865	ENDIF
	1866	!
[1]	1867	!-- Set outer and inner index arrays for non-flat topography.
	1868	!-- Here consistency checks concerning domain size and periodicity are
	1869	!-- necessary.
	1870	!-- Within this SELECT CASE structure only nzb_local is initialized
	1871	!-- individually depending on the chosen topography type, all other index
	1872	!-- arrays are initialized further below.
	1873	SELECT CASE ( TRIM( topography ) )
	1874
	1875	CASE ( 'flat' )
[2696]	1876	!
[2232]	1877	!-- Initialilize 3D topography array, used later for initializing flags
[4340]	1878	topo(nzb+1:nzt+1,:,:) = IBSET( topo(nzb+1:nzt+1,:,:), 0 )
	1879
	1880	CASE ( 'closed_channel' )
	1881	!
	1882	!-- Initialilize 3D topography array, used later for initializing flags
	1883	topo(nzb+1:nzt,:,:) = IBSET( topo(nzb+1:nzt,:,:), 0 )
[1]	1884
	1885	CASE ( 'single_building' )
	1886	!
	1887	!-- Single rectangular building, by default centered in the middle of the
	1888	!-- total domain
[4386]	1889	ngp_bx = NINT( building_length_x / dx )
	1890	ngp_by = NINT( building_length_y / dy )
[2232]	1891	bh = MINLOC( ABS( zw - building_height ), 1 ) - 1
	1892	IF ( ABS( zw(bh) - building_height ) == &
[1675]	1893	ABS( zw(bh+1) - building_height ) ) bh = bh + 1
[1322]	1894	IF ( building_wall_left == 9999999.9_wp ) THEN
[4386]	1895	building_wall_left = ( nx + 1 - ngp_bx ) / 2 * dx
[1]	1896	ENDIF
[4386]	1897	index_left_bwall = NINT( building_wall_left / dx )
	1898	index_right_bwall = index_left_bwall + ngp_bx
[1]	1899
[1322]	1900	IF ( building_wall_south == 9999999.9_wp ) THEN
[4386]	1901	building_wall_south = ( ny + 1 - ngp_by ) / 2 * dy
[1]	1902	ENDIF
[4386]	1903	index_south_bwall = NINT( building_wall_south / dy )
	1904	index_north_bwall = index_south_bwall + ngp_by
[1]	1905
	1906	!
	1907	!-- Building size has to meet some requirements
[4386]	1908	IF ( ( index_left_bwall < 1 ) .OR. ( index_right_bwall > nx-1 ) .OR. &
	1909	( index_right_bwall < index_left_bwall+3 ) .OR. &
	1910	( index_south_bwall < 1 ) .OR. ( index_north_bwall > ny-1 ) .OR.&
	1911	( index_north_bwall < index_south_bwall+3 ) ) THEN
[274]	1912	WRITE( message_string, * ) 'inconsistent building parameters:', &
[4386]	1913	'&index_left_bwall=', index_left_bwall, &
	1914	'index_right_bwall=', index_right_bwall, &
	1915	'index_south_bwall=', index_south_bwall, &
	1916	'index_north_bwall=', index_north_bwall, &
	1917	'nx=', nx, 'ny=', ny
[254]	1918	CALL message( 'init_grid', 'PA0203', 1, 2, 0, 6, 0 )
[1]	1919	ENDIF
	1920
[2696]	1921	ALLOCATE( nzb_local(nysg:nyng,nxlg:nxrg) )
[2892]	1922	nzb_local = 0
[1]	1923	!
[1968]	1924	!-- Define the building.
[4386]	1925	IF ( index_left_bwall <= nxr .AND. index_right_bwall >= nxl .AND. &
	1926	index_south_bwall <= nyn .AND. index_north_bwall >= nys ) &
	1927	nzb_local(MAX(nys,index_south_bwall):MIN(nyn,index_north_bwall), &
	1928	MAX(nxl,index_left_bwall):MIN(nxr,index_right_bwall)) = bh
[2232]	1929	!
[2696]	1930	!-- Set bit array on basis of nzb_local
	1931	DO i = nxl, nxr
	1932	DO j = nys, nyn
	1933	topo(nzb_local(j,i)+1:nzt+1,j,i) = &
	1934	IBSET( topo(nzb_local(j,i)+1:nzt+1,j,i), 0 )
[2232]	1935	ENDDO
	1936	ENDDO
[2696]	1937
	1938	DEALLOCATE( nzb_local )
[2232]	1939
[2696]	1940	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	1941	!
	1942	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	1943	!-- boundary conditions for topography.
	1944	IF ( .NOT. bc_ns_cyc ) THEN
	1945	IF ( nys == 0 ) THEN
	1946	DO i = 1, nbgp
	1947	topo(:,nys-i,:) = topo(:,nys,:)
	1948	ENDDO
	1949	ENDIF
	1950	IF ( nyn == ny ) THEN
	1951	DO i = 1, nbgp
	1952	topo(:,nyn+i,:) = topo(:,nyn,:)
	1953	ENDDO
	1954	ENDIF
	1955	ENDIF
	1956	IF ( .NOT. bc_lr_cyc ) THEN
	1957	IF ( nxl == 0 ) THEN
	1958	DO i = 1, nbgp
	1959	topo(:,:,nxl-i) = topo(:,:,nxl)
	1960	ENDDO
	1961	ENDIF
	1962	IF ( nxr == nx ) THEN
	1963	DO i = 1, nbgp
	1964	topo(:,:,nxr+i) = topo(:,:,nxr)
	1965	ENDDO
	1966	ENDIF
	1967	ENDIF
[2232]	1968
[240]	1969	CASE ( 'single_street_canyon' )
	1970	!
	1971	!-- Single quasi-2D street canyon of infinite length in x or y direction.
	1972	!-- The canyon is centered in the other direction by default.
[1322]	1973	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[240]	1974	!
	1975	!-- Street canyon in y direction
[4386]	1976	ngp_cx = NINT( canyon_width_x / dx )
[1322]	1977	IF ( canyon_wall_left == 9999999.9_wp ) THEN
[4386]	1978	canyon_wall_left = ( nx + 1 - ngp_cx ) / 2 * dx
[240]	1979	ENDIF
[4386]	1980	index_left_cwall= NINT( canyon_wall_left / dx )
	1981	index_right_cwall= index_left_cwall+ ngp_cx
[1322]	1982	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[240]	1983	!
	1984	!-- Street canyon in x direction
[4386]	1985	ngp_cy = NINT( canyon_width_y / dy )
[1322]	1986	IF ( canyon_wall_south == 9999999.9_wp ) THEN
[4386]	1987	canyon_wall_south = ( ny + 1 - ngp_cy ) / 2 * dy
[240]	1988	ENDIF
[4386]	1989	index_south_cwall = NINT( canyon_wall_south / dy )
	1990	index_north_cwall = index_south_cwall + ngp_cy
[2696]	1991
[240]	1992	ELSE
[254]	1993
	1994	message_string = 'no street canyon width given'
	1995	CALL message( 'init_grid', 'PA0204', 1, 2, 0, 6, 0 )
	1996
[240]	1997	ENDIF
	1998
[2232]	1999	ch = MINLOC( ABS( zw - canyon_height ), 1 ) - 1
	2000	IF ( ABS( zw(ch) - canyon_height ) == &
[1675]	2001	ABS( zw(ch+1) - canyon_height ) ) ch = ch + 1
[240]	2002	dp_level_ind_b = ch
	2003	!
	2004	!-- Street canyon size has to meet some requirements
[1322]	2005	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[4386]	2006	IF ( ( index_left_cwall< 1 ) .OR. ( index_right_cwall> nx-1 ) .OR.&
	2007	( ngp_cx < 3 ) .OR. ( ch < 3 ) ) THEN
[1353]	2008	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
[4386]	2009	'&index_left_cwall=', index_left_cwall, &
	2010	' index_right_cwall=', index_right_cwall, &
	2011	' ngp_cx=', ngp_cx, &
[3045]	2012	' ch=', ch, ' nx=', nx, ' ny=', ny
[254]	2013	CALL message( 'init_grid', 'PA0205', 1, 2, 0, 6, 0 )
[240]	2014	ENDIF
[1322]	2015	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[4386]	2016	IF ( ( index_south_cwall < 1 ) .OR. &
	2017	( index_north_cwall > ny-1 ) .OR. ( ngp_cy < 3 ) .OR. &
[2696]	2018	( ch < 3 ) ) THEN
[1353]	2019	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
[4386]	2020	'&index_south_cwall=', index_south_cwall, &
	2021	' index_north_cwall=', index_north_cwall, &
	2022	' ngp_cy=', ngp_cy, &
[3045]	2023	' ch=', ch, ' nx=', nx, ' ny=', ny
[254]	2024	CALL message( 'init_grid', 'PA0206', 1, 2, 0, 6, 0 )
[240]	2025	ENDIF
	2026	ENDIF
[1353]	2027	IF ( canyon_width_x /= 9999999.9_wp .AND. &
	2028	canyon_width_y /= 9999999.9_wp ) THEN
	2029	message_string = 'inconsistent canyon parameters:' // &
[3046]	2030	'&street canyon can only be oriented' // &
[3045]	2031	' either in x- or in y-direction'
[254]	2032	CALL message( 'init_grid', 'PA0207', 1, 2, 0, 6, 0 )
[240]	2033	ENDIF
	2034
[2696]	2035	ALLOCATE( nzb_local(nysg:nyng,nxlg:nxrg) )
[240]	2036	nzb_local = ch
[1322]	2037	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[4386]	2038	IF ( index_left_cwall<= nxr .AND. index_right_cwall>= nxl ) &
	2039	nzb_local(:,MAX(nxl,index_left_cwall+1):MIN(nxr,index_right_cwall-1)) = 0
[1322]	2040	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[4386]	2041	IF ( index_south_cwall <= nyn .AND. index_north_cwall >= nys ) &
	2042	nzb_local(MAX(nys,index_south_cwall+1):MIN(nyn,index_north_cwall-1),:) = 0
[240]	2043	ENDIF
[2232]	2044	!
[2696]	2045	!-- Set bit array on basis of nzb_local
	2046	DO i = nxl, nxr
	2047	DO j = nys, nyn
	2048	topo(nzb_local(j,i)+1:nzt+1,j,i) = &
	2049	IBSET( topo(nzb_local(j,i)+1:nzt+1,j,i), 0 )
[2232]	2050	ENDDO
	2051	ENDDO
[2696]	2052	DEALLOCATE( nzb_local )
[1994]	2053
[2696]	2054	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	2055	!
	2056	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	2057	!-- boundary conditions for topography.
	2058	IF ( .NOT. bc_ns_cyc ) THEN
	2059	IF ( nys == 0 ) THEN
	2060	DO i = 1, nbgp
	2061	topo(:,nys-i,:) = topo(:,nys,:)
	2062	ENDDO
	2063	ENDIF
	2064	IF ( nyn == ny ) THEN
	2065	DO i = 1, nbgp
	2066	topo(:,nyn+i,:) = topo(:,nyn,:)
	2067	ENDDO
	2068	ENDIF
	2069	ENDIF
	2070	IF ( .NOT. bc_lr_cyc ) THEN
	2071	IF ( nxl == 0 ) THEN
	2072	DO i = 1, nbgp
	2073	topo(:,:,nxl-i) = topo(:,:,nxl)
	2074	ENDDO
	2075	ENDIF
	2076	IF ( nxr == nx ) THEN
	2077	DO i = 1, nbgp
	2078	topo(:,:,nxr+i) = topo(:,:,nxr)
	2079	ENDDO
	2080	ENDIF
	2081	ENDIF
[2232]	2082
	2083	CASE ( 'tunnel' )
	2084
	2085	!
	2086	!-- Tunnel height
	2087	IF ( tunnel_height == 9999999.9_wp ) THEN
	2088	th = zw( INT( 0.2 * nz) )
	2089	ELSE
	2090	th = tunnel_height
	2091	ENDIF
	2092	!
	2093	!-- Tunnel-wall depth
[2696]	2094	IF ( tunnel_wall_depth == 9999999.9_wp ) THEN
[3065]	2095	td = MAX ( dx, dy, dz(1) )
[2232]	2096	ELSE
	2097	td = tunnel_wall_depth
	2098	ENDIF
	2099	!
	2100	!-- Check for tunnel width
	2101	IF ( tunnel_width_x == 9999999.9_wp .AND. &
	2102	tunnel_width_y == 9999999.9_wp ) THEN
	2103	message_string = 'No tunnel width is given. '
[2274]	2104	CALL message( 'init_grid', 'PA0280', 1, 2, 0, 6, 0 )
[2232]	2105	ENDIF
	2106	IF ( tunnel_width_x /= 9999999.9_wp .AND. &
	2107	tunnel_width_y /= 9999999.9_wp ) THEN
	2108	message_string = 'Inconsistent tunnel parameters:' // &
	2109	'tunnel can only be oriented' // &
	2110	'either in x- or in y-direction.'
[2274]	2111	CALL message( 'init_grid', 'PA0281', 1, 2, 0, 6, 0 )
[2232]	2112	ENDIF
	2113	!
[4356]	2114	!-- Check for too small tunnel width in x- and y-direction
	2115	IF ( tunnel_width_x /= 9999999.9_wp .AND. &
	2116	tunnel_width_x - 2.0_wp * td <= 2.0_wp * dx ) THEN
	2117	message_string = 'tunnel_width_x too small'
	2118	CALL message( 'init_grid', 'PA0175', 1, 2, 0, 6, 0 )
	2119	ENDIF
	2120	IF ( tunnel_width_y /= 9999999.9_wp .AND. &
	2121	tunnel_width_y - 2.0_wp * td <= 2.0_wp * dy ) THEN
	2122	message_string = 'tunnel_width_y too small'
	2123	CALL message( 'init_grid', 'PA0455', 1, 2, 0, 6, 0 )
	2124	ENDIF
	2125	!
	2126	!-- Check for too large tunnel width.
	2127	!-- Tunnel axis along y.
[2232]	2128	IF ( tunnel_width_x /= 9999999.9_wp ) THEN
	2129	IF ( tunnel_width_x > ( nx + 1 ) * dx ) THEN
[4356]	2130	message_string = 'tunnel_width_x too large'
[2274]	2131	CALL message( 'init_grid', 'PA0282', 1, 2, 0, 6, 0 )
[2232]	2132	ENDIF
	2133
	2134	txs_out = INT( ( nx + 1 ) * 0.5_wp * dx - tunnel_width_x * 0.5_wp )
	2135	txe_out = INT( ( nx + 1 ) * 0.5_wp * dx + tunnel_width_x * 0.5_wp )
	2136	txs_in = INT( ( nx + 1 ) * 0.5_wp * dx - &
	2137	( tunnel_width_x * 0.5_wp - td ) )
	2138	txe_in = INT( ( nx + 1 ) * 0.5_wp * dx + &
[2696]	2139	( tunnel_width_x * 0.5_wp - td ) )
[2232]	2140
	2141	tys_out = INT( ( ny + 1 ) * 0.5_wp * dy - tunnel_length * 0.5_wp )
	2142	tye_out = INT( ( ny + 1 ) * 0.5_wp * dy + tunnel_length * 0.5_wp )
	2143	tys_in = tys_out
	2144	tye_in = tye_out
	2145	ENDIF
	2146	!
[4356]	2147	!-- Tunnel axis along x.
[2232]	2148	IF ( tunnel_width_y /= 9999999.9_wp ) THEN
	2149	IF ( tunnel_width_y > ( ny + 1 ) * dy ) THEN
[4356]	2150	message_string = 'tunnel_width_y too large'
[2274]	2151	CALL message( 'init_grid', 'PA0456', 1, 2, 0, 6, 0 )
[2232]	2152	ENDIF
	2153
	2154	txs_out = INT( ( nx + 1 ) * 0.5_wp * dx - tunnel_length * 0.5_wp )
	2155	txe_out = INT( ( nx + 1 ) * 0.5_wp * dx + tunnel_length * 0.5_wp )
	2156	txs_in = txs_out
	2157	txe_in = txe_out
	2158
	2159	tys_out = INT( ( ny + 1 ) * 0.5_wp * dy - tunnel_width_y * 0.5_wp )
	2160	tye_out = INT( ( ny + 1 ) * 0.5_wp * dy + tunnel_width_y * 0.5_wp )
	2161	tys_in = INT( ( ny + 1 ) * 0.5_wp * dy - &
[2696]	2162	( tunnel_width_y * 0.5_wp - td ) )
[2232]	2163	tye_in = INT( ( ny + 1 ) * 0.5_wp * dy + &
	2164	( tunnel_width_y * 0.5_wp - td ) )
	2165	ENDIF
	2166
[2696]	2167	topo = 0
[2232]	2168	DO i = nxl, nxr
	2169	DO j = nys, nyn
	2170	!
	2171	!-- Use heaviside function to model outer tunnel surface
	2172	hv_out = th * 0.5_wp * &
	2173	( ( SIGN( 1.0_wp, i * dx - txs_out ) + 1.0_wp ) &
	2174	- ( SIGN( 1.0_wp, i * dx - txe_out ) + 1.0_wp ) )
	2175
	2176	hv_out = hv_out * 0.5_wp * &
	2177	( ( SIGN( 1.0_wp, j * dy - tys_out ) + 1.0_wp ) &
	2178	- ( SIGN( 1.0_wp, j * dy - tye_out ) + 1.0_wp ) )
[2696]	2179	!
[2232]	2180	!-- Use heaviside function to model inner tunnel surface
	2181	hv_in = ( th - td ) * 0.5_wp * &
	2182	( ( SIGN( 1.0_wp, i * dx - txs_in ) + 1.0_wp ) &
	2183	- ( SIGN( 1.0_wp, i * dx - txe_in ) + 1.0_wp ) )
	2184
	2185	hv_in = hv_in * 0.5_wp * &
	2186	( ( SIGN( 1.0_wp, j * dy - tys_in ) + 1.0_wp ) &
	2187	- ( SIGN( 1.0_wp, j * dy - tye_in ) + 1.0_wp ) )
	2188	!
	2189	!-- Set flags at x-y-positions without any tunnel surface
	2190	IF ( hv_out - hv_in == 0.0_wp ) THEN
[2696]	2191	topo(nzb+1:nzt+1,j,i) = IBSET( topo(nzb+1:nzt+1,j,i), 0 )
[2232]	2192	!
	2193	!-- Set flags at x-y-positions with tunnel surfaces
	2194	ELSE
	2195	DO k = nzb + 1, nzt + 1
	2196	!
	2197	!-- Inner tunnel
	2198	IF ( hv_out - hv_in == th ) THEN
	2199	IF ( zw(k) <= hv_out ) THEN
[2696]	2200	topo(k,j,i) = IBCLR( topo(k,j,i), 0 )
[2232]	2201	ELSE
[2696]	2202	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2203	ENDIF
	2204	ENDIF
	2205	!
	2206	!-- Lateral tunnel walls
	2207	IF ( hv_out - hv_in == td ) THEN
	2208	IF ( zw(k) <= hv_in ) THEN
[2696]	2209	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2210	ELSEIF ( zw(k) > hv_in .AND. zw(k) <= hv_out ) THEN
[2696]	2211	topo(k,j,i) = IBCLR( topo(k,j,i), 0 )
[2232]	2212	ELSEIF ( zw(k) > hv_out ) THEN
[2696]	2213	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2214	ENDIF
	2215	ENDIF
	2216	ENDDO
	2217	ENDIF
	2218	ENDDO
	2219	ENDDO
	2220
[2696]	2221	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	2222	!
	2223	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	2224	!-- boundary conditions for topography.
	2225	IF ( .NOT. bc_ns_cyc ) THEN
	2226	IF ( nys == 0 ) THEN
	2227	DO i = 1, nbgp
	2228	topo(:,nys-i,:) = topo(:,nys,:)
	2229	ENDDO
	2230	ENDIF
	2231	IF ( nyn == ny ) THEN
	2232	DO i = 1, nbgp
	2233	topo(:,nyn+i,:) = topo(:,nyn,:)
	2234	ENDDO
	2235	ENDIF
	2236	ENDIF
	2237	IF ( .NOT. bc_lr_cyc ) THEN
	2238	IF ( nxl == 0 ) THEN
	2239	DO i = 1, nbgp
	2240	topo(:,:,nxl-i) = topo(:,:,nxl)
	2241	ENDDO
	2242	ENDIF
	2243	IF ( nxr == nx ) THEN
	2244	DO i = 1, nbgp
	2245	topo(:,:,nxr+i) = topo(:,:,nxr)
	2246	ENDDO
	2247	ENDIF
	2248	ENDIF
[2232]	2249
[1]	2250	CASE ( 'read_from_file' )
	2251	!
[2696]	2252	!-- Note, topography information have been already read.
	2253	!-- If required, further process topography, i.e. reference buildings on
	2254	!-- top of orography and set temporary 3D topography array, which is
	2255	!-- used later to set grid flags. Calling of this rouinte is also
	2256	!-- required in case of ASCII input, even though no distinction between
	2257	!-- terrain- and building height is made in this case.
	2258	CALL process_topography( topo )
[1968]	2259	!
[2696]	2260	!-- Filter holes resolved by only one grid-point
	2261	CALL filter_topography( topo )
[1968]	2262	!
[2696]	2263	!-- Exchange ghost-points, as well as add cyclic or Neumann boundary
	2264	!-- conditions.
	2265	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2266	!
[4314]	2267	!-- Set lateral boundary conditions for topography on all ghost layers
[1968]	2268	IF ( .NOT. bc_ns_cyc ) THEN
[2550]	2269	IF ( nys == 0 ) THEN
[2696]	2270	DO i = 1, nbgp
	2271	topo(:,nys-i,:) = topo(:,nys,:)
	2272	ENDDO
[2550]	2273	ENDIF
[2696]	2274	IF ( nyn == ny ) THEN
	2275	DO i = 1, nbgp
	2276	topo(:,nyn+i,:) = topo(:,nyn,:)
	2277	ENDDO
	2278	ENDIF
[1942]	2279	ENDIF
[1910]	2280
[1968]	2281	IF ( .NOT. bc_lr_cyc ) THEN
[2550]	2282	IF ( nxl == 0 ) THEN
[2696]	2283	DO i = 1, nbgp
	2284	topo(:,:,nxl-i) = topo(:,:,nxl)
[2232]	2285	ENDDO
[2696]	2286	ENDIF
	2287	IF ( nxr == nx ) THEN
	2288	DO i = 1, nbgp
	2289	topo(:,:,nxr+i) = topo(:,:,nxr)
	2290	ENDDO
	2291	ENDIF
[2232]	2292	ENDIF
	2293
[667]	2294
[1]	2295	CASE DEFAULT
[2696]	2296	!
[1]	2297	!-- The DEFAULT case is reached either if the parameter topography
[217]	2298	!-- contains a wrong character string or if the user has defined a special
[1]	2299	!-- case in the user interface. There, the subroutine user_init_grid
	2300	!-- checks which of these two conditions applies.
[2696]	2301	CALL user_init_grid( topo )
	2302	CALL filter_topography( topo )
[1]	2303
	2304	END SELECT
	2305	!
	2306	!-- Consistency checks and index array initialization are only required for
[2696]	2307	!-- non-flat topography.
[1]	2308	IF ( TRIM( topography ) /= 'flat' ) THEN
	2309	!
[2232]	2310	!-- In case of non-flat topography, check whether the convention how to
	2311	!-- define the topography grid has been set correctly, or whether the default
	2312	!-- is applicable. If this is not possible, abort.
	2313	IF ( TRIM( topography_grid_convention ) == ' ' ) THEN
[4340]	2314	IF ( TRIM( topography ) /= 'closed_channel' .AND. &
	2315	TRIM( topography ) /= 'single_building' .AND. &
[2232]	2316	TRIM( topography ) /= 'single_street_canyon' .AND. &
	2317	TRIM( topography ) /= 'tunnel' .AND. &
	2318	TRIM( topography ) /= 'read_from_file') THEN
	2319	!-- The default value is not applicable here, because it is only valid
[3045]	2320	!-- for the four standard cases 'single_building',
	2321	!-- 'single_street_canyon', 'tunnel' and 'read_from_file'
[2232]	2322	!-- defined in init_grid.
	2323	WRITE( message_string, * ) &
[2696]	2324	'The value for "topography_grid_convention" ', &
[3046]	2325	'is not set. Its default value is & only valid for ', &
[3045]	2326	'"topography" = ''single_building'', ''tunnel'' ', &
[4340]	2327	'''single_street_canyon'', ''closed_channel'' & or ', &
	2328	'''read_from_file''.', &
[3046]	2329	'& Choose ''cell_edge'' or ''cell_center''.'
[2232]	2330	CALL message( 'init_grid', 'PA0239', 1, 2, 0, 6, 0 )
	2331	ELSE
	2332	!-- The default value is applicable here.
	2333	!-- Set convention according to topography.
	2334	IF ( TRIM( topography ) == 'single_building' .OR. &
	2335	TRIM( topography ) == 'single_street_canyon' ) THEN
	2336	topography_grid_convention = 'cell_edge'
	2337	ELSEIF ( TRIM( topography ) == 'read_from_file' .OR. &
	2338	TRIM( topography ) == 'tunnel') THEN
	2339	topography_grid_convention = 'cell_center'
	2340	ENDIF
	2341	ENDIF
	2342	ELSEIF ( TRIM( topography_grid_convention ) /= 'cell_edge' .AND. &
	2343	TRIM( topography_grid_convention ) /= 'cell_center' ) THEN
	2344	WRITE( message_string, * ) &
[2696]	2345	'The value for "topography_grid_convention" is ', &
[3046]	2346	'not recognized.& Choose ''cell_edge'' or ''cell_center''.'
[2232]	2347	CALL message( 'init_grid', 'PA0240', 1, 2, 0, 6, 0 )
	2348	ENDIF
[1]	2349
[2169]	2350
[217]	2351	IF ( topography_grid_convention == 'cell_edge' ) THEN
[134]	2352	!
[217]	2353	!-- The array nzb_local as defined using the 'cell_edge' convention
	2354	!-- describes the actual total size of topography which is defined at the
	2355	!-- cell edges where u=0 on the topography walls in x-direction and v=0
	2356	!-- on the topography walls in y-direction. However, PALM uses individual
	2357	!-- arrays nzb_u\|v\|w\|s_inner\|outer that are based on nzb_s_inner.
	2358	!-- Therefore, the extent of topography in nzb_local is now reduced by
	2359	!-- 1dx at the E topography walls and by 1dy at the N topography walls
[1968]	2360	!-- to form the basis for nzb_s_inner.
	2361	!-- Note, the reverse memory access (i-j instead of j-i) is absolutely
	2362	!-- required at this point.
	2363	DO j = nys+1, nyn+1
	2364	DO i = nxl-1, nxr
[2232]	2365	DO k = nzb, nzt+1
[2696]	2366	IF ( BTEST( topo(k,j,i), 0 ) .OR. &
	2367	BTEST( topo(k,j,i+1), 0 ) ) &
	2368	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2369	ENDDO
	2370	ENDDO
	2371	ENDDO
[2696]	2372	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2373
	2374	DO i = nxl, nxr+1
	2375	DO j = nys-1, nyn
	2376	DO k = nzb, nzt+1
[2696]	2377	IF ( BTEST( topo(k,j,i), 0 ) .OR. &
	2378	BTEST( topo(k,j+1,i), 0 ) ) &
	2379	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2380	ENDDO
	2381	ENDDO
	2382	ENDDO
[2696]	2383	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2384
[217]	2385	ENDIF
[2696]	2386	ENDIF
[2232]	2387
[1]	2388
[2696]	2389	END SUBROUTINE init_topo
[1]	2390
[2696]	2391	SUBROUTINE set_topo_flags(topo)
[1]	2392
[2696]	2393	USE control_parameters, &
[4294]	2394	ONLY: bc_lr_cyc, bc_ns_cyc, constant_flux_layer, &
	2395	scalar_advec, topography, use_surface_fluxes, use_top_fluxes
[1]	2396
[2696]	2397	USE indices, &
[3241]	2398	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, &
[4346]	2399	nzt, topo_top_ind, wall_flags_static_0, wall_flags_total_0
[1]	2400
[2696]	2401	USE kinds
[1]	2402
[2696]	2403	IMPLICIT NONE
[1804]	2404
[2696]	2405	INTEGER(iwp) :: i !< index variable along x
[4168]	2406	INTEGER(iwp) :: ibit !< integer bit position of topgraphy masking array
[2696]	2407	INTEGER(iwp) :: j !< index variable along y
	2408	INTEGER(iwp) :: k !< index variable along z
[1]	2409
[2696]	2410	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo !< input array for 3D topography and dummy array for setting "outer"-flags
[2232]	2411
[4329]	2412	ALLOCATE( wall_flags_static_0(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	2413	wall_flags_static_0 = 0
[2232]	2414	!
[2696]	2415	!-- Set-up topography flags. First, set flags only for s, u, v and w-grid.
	2416	!-- Further special flags will be set in following loops.
[2232]	2417	DO i = nxl, nxr
	2418	DO j = nys, nyn
	2419	DO k = nzb, nzt+1
	2420	!
	2421	!-- scalar grid
[4340]	2422	IF ( BTEST( topo(k,j,i), 0 ) ) &
[4329]	2423	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 0 )
[2232]	2424	!
[2696]	2425	!-- u grid
[4340]	2426	IF ( BTEST( topo(k,j,i), 0 ) .AND. &
	2427	BTEST( topo(k,j,i-1), 0 ) ) &
[4329]	2428	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 1 )
[2696]	2429	!
[2232]	2430	!-- v grid
[4340]	2431	IF ( BTEST( topo(k,j,i), 0 ) .AND. &
	2432	BTEST( topo(k,j-1,i), 0 ) ) &
[4329]	2433	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 2 )
[2696]	2434
[2232]	2435	ENDDO
[1]	2436
[2232]	2437	DO k = nzb, nzt
[1]	2438	!
[2232]	2439	!-- w grid
[4340]	2440	IF ( BTEST( topo(k,j,i), 0 ) .AND. &
	2441	BTEST( topo(k+1,j,i), 0 ) ) &
[4329]	2442	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 3 )
[2232]	2443	ENDDO
[4340]	2444
	2445	IF ( topography /= 'closed_channel' ) THEN
	2446	wall_flags_static_0(nzt+1,j,i) = IBSET( wall_flags_static_0(nzt+1,j,i), 3 )
	2447	ENDIF
[2232]	2448
	2449	ENDDO
	2450	ENDDO
[2696]	2451
[4329]	2452	CALL exchange_horiz_int( wall_flags_static_0, nys, nyn, nxl, nxr, nzt, nbgp )
[4346]	2453
[1]	2454	!
[4115]	2455	!-- Set outer array for scalars to mask near-surface grid points. Note, on
	2456	!-- basis of flag 24 futher flags will be derived which are used to control
	2457	!-- production of subgrid TKE production near walls.
[4346]	2458
	2459	ALLOCATE( wall_flags_total_0(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	2460	wall_flags_total_0 = 0
	2461
[2696]	2462	DO i = nxl, nxr
	2463	DO j = nys, nyn
[2232]	2464	DO k = nzb, nzt+1
[4346]	2465	wall_flags_total_0(k,j,i) = IOR( wall_flags_total_0(k,j,i), wall_flags_static_0(k,j,i) )
[2232]	2466	ENDDO
	2467	ENDDO
	2468	ENDDO
[4346]	2469
	2470	CALL exchange_horiz_int( wall_flags_total_0, nys, nyn, nxl, nxr, nzt, nbgp )
	2471
	2472	DO i = nxl, nxr
	2473	DO j = nys, nyn
	2474	DO k = nzb, nzt+1
	2475	IF ( BTEST( wall_flags_total_0(k,j-1,i), 0 ) .AND. &
	2476	BTEST( wall_flags_total_0(k,j+1,i), 0 ) .AND. &
	2477	BTEST( wall_flags_total_0(k,j,i-1), 0 ) .AND. &
	2478	BTEST( wall_flags_total_0(k,j,i+1), 0 ) .AND. &
	2479	BTEST( wall_flags_total_0(k,j-1,i-1), 0 ) .AND. &
	2480	BTEST( wall_flags_total_0(k,j+1,i-1), 0 ) .AND. &
	2481	BTEST( wall_flags_total_0(k,j-1,i+1), 0 ) .AND. &
	2482	BTEST( wall_flags_total_0(k,j+1,i+1), 0 ) ) &
	2483	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 24 )
	2484	ENDDO
	2485	ENDDO
	2486	ENDDO
[1]	2487	!
[2232]	2488	!-- Set further special flags
	2489	DO i = nxl, nxr
	2490	DO j = nys, nyn
	2491	DO k = nzb, nzt+1
[1]	2492	!
[2232]	2493	!-- scalar grid, former nzb_diff_s_inner.
	2494	!-- Note, use this flag also to mask topography in diffusion_u and
	2495	!-- diffusion_v along the vertical direction. In case of
	2496	!-- use_surface_fluxes, fluxes are calculated via MOST, else, simple
	2497	!-- gradient approach is applied. Please note, in case of u- and v-
	2498	!-- diffuison, a small error is made at edges (on the east side for u,
	2499	!-- at the north side for v), since topography on scalar grid point
	2500	!-- is used instead of topography on u/v-grid. As number of topography grid
	2501	!-- points on uv-grid is different than s-grid, different number of
	2502	!-- surface elements would be required. In order to avoid this,
	2503	!-- treat edges (u(k,j,i+1)) simply by a gradient approach, i.e. these
	2504	!-- points are not masked within diffusion_u. Tests had shown that the
	2505	!-- effect on the flow is negligible.
	2506	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2507	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2508	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 8 )
[2232]	2509	ELSE
[4346]	2510	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 8 )
[2232]	2511	ENDIF
[1]	2512
[2232]	2513	ENDDO
	2514	!
	2515	!-- Special flag to control vertical diffusion at model top - former
	2516	!-- nzt_diff
[4346]	2517	wall_flags_total_0(:,j,i) = IBSET( wall_flags_total_0(:,j,i), 9 )
[2232]	2518	IF ( use_top_fluxes ) &
[4346]	2519	wall_flags_total_0(nzt+1,j,i) = IBCLR( wall_flags_total_0(nzt+1,j,i), 9 )
[1]	2520
[2696]	2521
[2232]	2522	DO k = nzb+1, nzt
	2523	!
	2524	!-- Special flag on u grid, former nzb_u_inner + 1, required
	2525	!-- for disturb_field and initialization. Do not disturb directly at
	2526	!-- topography, as well as initialize u with zero one grid point outside
	2527	!-- of topography.
[4346]	2528	IF ( BTEST( wall_flags_total_0(k-1,j,i), 1 ) .AND. &
	2529	BTEST( wall_flags_total_0(k,j,i), 1 ) .AND. &
	2530	BTEST( wall_flags_total_0(k+1,j,i), 1 ) ) &
	2531	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 20 )
[2232]	2532	!
	2533	!-- Special flag on v grid, former nzb_v_inner + 1, required
	2534	!-- for disturb_field and initialization. Do not disturb directly at
	2535	!-- topography, as well as initialize v with zero one grid point outside
	2536	!-- of topography.
[4346]	2537	IF ( BTEST( wall_flags_total_0(k-1,j,i), 2 ) .AND. &
	2538	BTEST( wall_flags_total_0(k,j,i), 2 ) .AND. &
	2539	BTEST( wall_flags_total_0(k+1,j,i), 2 ) ) &
	2540	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 21 )
[2232]	2541	!
	2542	!-- Special flag on scalar grid, former nzb_s_inner+1. Used for
	2543	!-- lpm_sgs_tke
[4346]	2544	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2545	BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2546	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2547	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 25 )
[2232]	2548	!
	2549	!-- Special flag on scalar grid, nzb_diff_s_outer - 1, required in
	2550	!-- in production_e
	2551	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2552	IF ( BTEST( wall_flags_total_0(k,j,i), 24 ) .AND. &
	2553	BTEST( wall_flags_total_0(k-1,j,i), 24 ) .AND. &
	2554	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2555	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 29 )
[2232]	2556	ELSE
[4346]	2557	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2558	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 29 )
[1]	2559	ENDIF
[2232]	2560	!
	2561	!-- Special flag on scalar grid, nzb_diff_s_outer - 1, required in
	2562	!-- in production_e
	2563	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2564	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2565	BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2566	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2567	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 30 )
[2232]	2568	ELSE
[4346]	2569	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2570	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 30 )
[2232]	2571	ENDIF
	2572	ENDDO
	2573	!
	2574	!-- Flags indicating downward facing walls
[4340]	2575	DO k = nzb+1, nzt+1
[2232]	2576	!
	2577	!-- Scalar grid
[4346]	2578	IF ( BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2579	.NOT. BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2580	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 13 )
[2232]	2581	!
	2582	!-- Downward facing wall on u grid
[4346]	2583	IF ( BTEST( wall_flags_total_0(k-1,j,i), 1 ) .AND. &
	2584	.NOT. BTEST( wall_flags_total_0(k,j,i), 1 ) ) &
	2585	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 15 )
[2232]	2586	!
	2587	!-- Downward facing wall on v grid
[4346]	2588	IF ( BTEST( wall_flags_total_0(k-1,j,i), 2 ) .AND. &
	2589	.NOT. BTEST( wall_flags_total_0(k,j,i), 2 ) ) &
	2590	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 17 )
[2232]	2591	!
	2592	!-- Downward facing wall on w grid
[4346]	2593	IF ( BTEST( wall_flags_total_0(k-1,j,i), 3 ) .AND. &
	2594	.NOT. BTEST( wall_flags_total_0(k,j,i), 3 ) ) &
	2595	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 19 )
[2232]	2596	ENDDO
	2597	!
	2598	!-- Flags indicating upward facing walls
	2599	DO k = nzb, nzt
	2600	!
	2601	!-- Upward facing wall on scalar grid
[4346]	2602	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2603	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2604	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 12 )
[2232]	2605	!
	2606	!-- Upward facing wall on u grid
[4346]	2607	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 1 ) .AND. &
	2608	BTEST( wall_flags_total_0(k+1,j,i), 1 ) ) &
	2609	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 14 )
[1]	2610
[2696]	2611	!
[2232]	2612	!-- Upward facing wall on v grid
[4346]	2613	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 2 ) .AND. &
	2614	BTEST( wall_flags_total_0(k+1,j,i), 2 ) ) &
	2615	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 16 )
[2696]	2616
[2232]	2617	!
	2618	!-- Upward facing wall on w grid
[4346]	2619	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 3 ) .AND. &
	2620	BTEST( wall_flags_total_0(k+1,j,i), 3 ) ) &
	2621	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 18 )
[2232]	2622	!
	2623	!-- Special flag on scalar grid, former nzb_s_inner
[4346]	2624	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .OR. &
	2625	BTEST( wall_flags_total_0(k,j,i), 12 ) .OR. &
	2626	BTEST( wall_flags_total_0(k,j,i), 13 ) ) &
	2627	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 22 )
[2232]	2628	!
	2629	!-- Special flag on scalar grid, nzb_diff_s_inner - 1, required for
	2630	!-- flow_statistics
	2631	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2632	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2633	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2634	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 23 )
[2232]	2635	ELSE
[4346]	2636	IF ( BTEST( wall_flags_total_0(k,j,i), 22 ) ) &
	2637	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 23 )
[1]	2638	ENDIF
[2696]	2639
[1]	2640
[2232]	2641	ENDDO
[4346]	2642	wall_flags_total_0(nzt+1,j,i) = IBSET( wall_flags_total_0(nzt+1,j,i), 22 )
	2643	wall_flags_total_0(nzt+1,j,i) = IBSET( wall_flags_total_0(nzt+1,j,i), 23 )
[4109]	2644	!
	2645	!-- Set flags indicating that topography is close by in horizontal
	2646	!-- direction, i.e. flags that infold the topography. These will be used
	2647	!-- to set advection flags for passive scalars, where due to large
	2648	!-- gradients near buildings stationary numerical oscillations can produce
	2649	!-- unrealistically high concentrations. This is only necessary if
	2650	!-- WS-scheme is applied for scalar advection. Note, these flags will be
	2651	!-- only used for passive scalars such as chemical species or aerosols.
	2652	IF ( scalar_advec == 'ws-scheme' ) THEN
	2653	DO k = nzb, nzt
[4346]	2654	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. ( &
	2655	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-1), 0 ) ) .OR.&
	2656	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-2), 0 ) ) .OR.&
	2657	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-3), 0 ) ) .OR.&
	2658	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+1), 0 ) ) .OR.&
	2659	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+2), 0 ) ) .OR.&
	2660	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+3), 0 ) ) .OR.&
	2661	ANY( .NOT. BTEST( wall_flags_total_0(k,j-1,i-3:i+3), 0 ) ) .OR.&
	2662	ANY( .NOT. BTEST( wall_flags_total_0(k,j-2,i-3:i+3), 0 ) ) .OR.&
	2663	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3,i-3:i+3), 0 ) ) .OR.&
	2664	ANY( .NOT. BTEST( wall_flags_total_0(k,j+1,i-3:i+3), 0 ) ) .OR.&
	2665	ANY( .NOT. BTEST( wall_flags_total_0(k,j+2,i-3:i+3), 0 ) ) .OR.&
	2666	ANY( .NOT. BTEST( wall_flags_total_0(k,j+3,i-3:i+3), 0 ) ) &
	2667	) ) &
	2668	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 31 )
[4109]	2669
	2670	ENDDO
	2671	ENDIF
[2232]	2672	ENDDO
	2673	ENDDO
	2674	!
[2696]	2675	!-- Finally, set identification flags indicating natural terrain or buildings.
[4189]	2676	!-- Natural terrain grid points. Information on the type of the surface is
	2677	!-- stored in bit 1 of 3D Integer array topo. However, this bit is only set
	2678	!-- when topography is read from file. In order to run the land-surface model
	2679	!-- also without topography information, set bit 1 explicitely in this case.
[4294]	2680	!--
	2681	!-- Natural terrain grid points
	2682	!-- If no topography is initialized, the land-surface is at k = nzb.
	2683	IF ( TRIM( topography ) /= 'read_from_file' ) THEN
[4329]	2684	wall_flags_static_0(nzb,:,:) = IBSET( wall_flags_static_0(nzb,:,:), 5 )
[4294]	2685	ELSE
	2686	DO i = nxl, nxr
	2687	DO j = nys, nyn
	2688	DO k = nzb, nzt+1
[4189]	2689	!
[4294]	2690	!-- Natural terrain grid point
	2691	IF ( BTEST( topo(k,j,i), 1 ) ) &
[4329]	2692	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 5 )
[2696]	2693	ENDDO
	2694	ENDDO
[4294]	2695	ENDDO
[2696]	2696	ENDIF
	2697	!
	2698	!-- Building grid points.
[4294]	2699	DO i = nxl, nxr
	2700	DO j = nys, nyn
	2701	DO k = nzb, nzt+1
	2702	IF ( BTEST( topo(k,j,i), 2 ) ) &
[4329]	2703	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 6 )
[2696]	2704	ENDDO
	2705	ENDDO
[4294]	2706	ENDDO
[2696]	2707	!
[4314]	2708	!-- Set flag 4, indicating new topography grid points due to filtering.
	2709	DO i = nxl, nxr
	2710	DO j = nys, nyn
	2711	DO k = nzb, nzt+1
	2712	IF ( BTEST( topo(k,j,i), 4 ) ) &
[4329]	2713	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 4 )
[4314]	2714	ENDDO
	2715	ENDDO
	2716	ENDDO
[4346]	2717
	2718	CALL exchange_horiz_int( wall_flags_static_0, nys, nyn, nxl, nxr, nzt, nbgp )
	2719
	2720	DO i = nxl, nxr
	2721	DO j = nys, nyn
	2722	DO k = nzb, nzt+1
	2723	wall_flags_total_0(k,j,i) = IOR( wall_flags_total_0(k,j,i), wall_flags_static_0(k,j,i) )
	2724	ENDDO
	2725	ENDDO
	2726	ENDDO
[4314]	2727	!
[2232]	2728	!-- Exchange ghost points for wall flags
[4346]	2729	CALL exchange_horiz_int( wall_flags_total_0, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2730	!
	2731	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	2732	!-- boundary conditions for topography.
	2733	IF ( .NOT. bc_ns_cyc ) THEN
[2696]	2734	IF ( nys == 0 ) THEN
	2735	DO i = 1, nbgp
[4346]	2736	wall_flags_total_0(:,nys-i,:) = wall_flags_total_0(:,nys,:)
[2696]	2737	ENDDO
	2738	ENDIF
	2739	IF ( nyn == ny ) THEN
	2740	DO i = 1, nbgp
[4346]	2741	wall_flags_total_0(:,nyn+i,:) = wall_flags_total_0(:,nyn,:)
[2696]	2742	ENDDO
	2743	ENDIF
[2232]	2744	ENDIF
	2745	IF ( .NOT. bc_lr_cyc ) THEN
[2696]	2746	IF ( nxl == 0 ) THEN
	2747	DO i = 1, nbgp
[4346]	2748	wall_flags_total_0(:,:,nxl-i) = wall_flags_total_0(:,:,nxl)
[2696]	2749	ENDDO
[2232]	2750	ENDIF
[2696]	2751	IF ( nxr == nx ) THEN
	2752	DO i = 1, nbgp
[4346]	2753	wall_flags_total_0(:,:,nxr+i) = wall_flags_total_0(:,:,nxr)
[2232]	2754	ENDDO
[2696]	2755	ENDIF
[2232]	2756	ENDIF
[4168]	2757	!
	2758	!-- Pre-calculate topography top indices (former get_topography_top_index
	2759	!-- function)
	2760	ALLOCATE( topo_top_ind(nysg:nyng,nxlg:nxrg,0:4) )
	2761	!
	2762	!-- Uppermost topography index on scalar grid
	2763	ibit = 12
	2764	topo_top_ind(:,:,0) = MAXLOC( &
	2765	MERGE( 1, 0, &
[4346]	2766	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2767	), DIM = 1 &
	2768	) - 1
	2769	!
	2770	!-- Uppermost topography index on u grid
	2771	ibit = 14
	2772	topo_top_ind(:,:,1) = MAXLOC( &
	2773	MERGE( 1, 0, &
[4346]	2774	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2775	), DIM = 1 &
	2776	) - 1
	2777	!
	2778	!-- Uppermost topography index on v grid
	2779	ibit = 16
	2780	topo_top_ind(:,:,2) = MAXLOC( &
	2781	MERGE( 1, 0, &
[4346]	2782	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2783	), DIM = 1 &
	2784	) - 1
	2785	!
	2786	!-- Uppermost topography index on w grid
	2787	ibit = 18
	2788	topo_top_ind(:,:,3) = MAXLOC( &
	2789	MERGE( 1, 0, &
[4346]	2790	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2791	), DIM = 1 &
	2792	) - 1
	2793	!
	2794	!-- Uppermost topography index on scalar outer grid
	2795	ibit = 24
	2796	topo_top_ind(:,:,4) = MAXLOC( &
	2797	MERGE( 1, 0, &
[4346]	2798	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2799	), DIM = 1 &
	2800	) - 1
[4346]	2801
[2696]	2802	END SUBROUTINE set_topo_flags
[114]	2803
	2804
	2805

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

Download in other formats:

| Impressum | ©Leibniz Universität Hannover |