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source: palm/trunk/SOURCE/init_grid.f90 @ 4631

Last change on this file since 4631 was 4630, checked in by suehring, 4 years ago
Land-surface model: bugfix in level 3 initialization of root-area-density; Avoid double classifiation of vertical walls (at surfaces that are alo covered by buildings); Land/urban surface: bugfix in resistance calculation - avoid potential divisions by zero; init_grid: in case of ASCII topography flag grid points as terrain and building to allow application of land/urban-surface model
Property svn:keywords set to `Id`
File size: 118.4 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	! -----------------
[4601]	22	!
	23	!
[2233]	24	! Former revisions:
	25	! -----------------
	26	! $Id: init_grid.f90 4630 2020-07-30 14:54:34Z suehring $
[4630]	27	! In case of ASCII topography input flag grid points as terrain and building.
	28	!
	29	! 4601 2020-07-14 12:06:09Z suehring
[4601]	30	! Minor formatting adjustments
	31	!
	32	! 4564 2020-06-12 14:03:36Z raasch
[4564]	33	! Vertical nesting method of Huq et al. (2019) removed
	34	!
	35	! 4543 2020-05-20 14:12:22Z gronemeier
[4543]	36	! Remove non-required check for canyon height
	37	!
	38	! 4507 2020-04-22 18:21:45Z gronemeier
[4507]	39	! update origin_z with shifting height of orography (oro_min)
	40	!
	41	! 4457 2020-03-11 14:20:43Z raasch
[4457]	42	! use statement for exchange horiz added,
	43	! bugfix for call of exchange horiz 2d
	44	!
	45	! 4444 2020-03-05 15:59:50Z raasch
[4444]	46	! bugfix: cpp-directives for serial mode added
	47	!
	48	! 4414 2020-02-19 20:16:04Z suehring
[4414]	49	! - Remove deprecated topography arrays nzb_s_inner, nzb_u_inner, etc.
	50	! - Move initialization of boundary conditions and multigrid into an extra
	51	! module interface.
	52	!
	53	! 4386 2020-01-27 15:07:30Z Giersch
[4386]	54	! Allocation statements, comments, naming of variables revised and _wp added to
	55	! real type values
	56	!
	57	! 4360 2020-01-07 11:25:50Z suehring
[4356]	58	! Revise error messages for generic tunnel setup.
	59	!
	60	! 4346 2019-12-18 11:55:56Z motisi
[4346]	61	! Introduction of wall_flags_total_0, which currently sets bits based on static
	62	! topography information used in wall_flags_static_0
	63	!
	64	! 4340 2019-12-16 08:17:03Z Giersch
[4340]	65	! Topography closed channel flow with symmetric boundaries implemented
	66	!
	67	! 4329 2019-12-10 15:46:36Z motisi
[4329]	68	! Renamed wall_flags_0 to wall_flags_static_0
	69	!
	70	! 4328 2019-12-09 18:53:04Z suehring
[4328]	71	! Minor change in nzb_max computation. Commentation added.
	72	!
	73	! 4314 2019-11-29 10:29:20Z suehring
[4314]	74	! Set additional topography flag 4 to mark topography grid points emerged
	75	! from the filtering process.
	76	!
	77	! 4294 2019-11-13 18:34:16Z suehring
[4294]	78	! Bugfix, always set bit 5 and 6 of wall_flags, indicating terrain- and
	79	! building surfaces in all cases, in order to enable terrain-following output
	80	! also when no land- or urban-surface model is applied.
	81	!
	82	! 4265 2019-10-15 16:16:24Z suehring
[4265]	83	! Bugfix for last commit, exchange oro_max variable only when it is allocated
	84	! (not necessarily the case when topography is input from ASCII file).
	85	!
	86	! 4245 2019-09-30 08:40:37Z pavelkrc
[4245]	87	! Store oro_max (building z-offset) in 2D for building surfaces
	88	!
	89	! 4189 2019-08-26 16:19:38Z suehring
[4189]	90	! - Add check for proper setting of namelist parameter topography
	91	! - Set flag to indicate land surfaces in case no topography is provided
	92	!
	93	! 4182 2019-08-22 15:20:23Z scharf
[4182]	94	! Corrected "Former revisions" section
	95	!
	96	! 4168 2019-08-16 13:50:17Z suehring
[4168]	97	! Pre-calculate topography top index and store it on an array (replaces former
	98	! functions get_topography_top_index)
	99	!
	100	! 4159 2019-08-15 13:31:35Z suehring
[4159]	101	! Revision of topography processing. This was not consistent between 2D and 3D
	102	! buildings.
	103	!
	104	! 4144 2019-08-06 09:11:47Z raasch
[4144]	105	! relational operators .EQ., .NE., etc. replaced by ==, /=, etc.
	106	!
	107	! 4115 2019-07-24 12:50:49Z suehring
[4115]	108	! Bugfix in setting near-surface flag 24, inidicating wall-bounded grid points
	109	!
	110	! 4110 2019-07-22 17:05:21Z suehring
[4110]	111	! - Separate initialization of advection flags for momentum and scalars.
	112	! - Change subroutine interface for ws_init_flags_scalar to pass boundary flags
	113	!
	114	! 4109 2019-07-22 17:00:34Z suehring
[3927]	115	! Fix bad commit
	116	!
	117	! 3926 2019-04-23 12:56:42Z suehring
[3925]	118	! Minor bugfix in building mapping when all building IDs in the model domain
	119	! are missing
	120	!
	121	! 3857 2019-04-03 13:00:16Z knoop
[3855]	122	! In projection of non-building 3D objects onto numerical grid remove
	123	! dependency on building_type
	124	!
	125	! 3763 2019-02-25 17:33:49Z suehring
[3763]	126	! Replace work-around for ghost point exchange of 1-byte arrays with specific
	127	! routine as already done in other routines
	128	!
	129	! 3761 2019-02-25 15:31:42Z raasch
[3761]	130	! unused variables removed
	131	!
	132	! 3661 2019-01-08 18:22:50Z suehring
[3661]	133	! Remove setting of nzb_max to nzt at non-cyclic boundary PEs, instead,
	134	! order degradation of advection scheme is handeled directly in advec_ws
	135	!
	136	! 3655 2019-01-07 16:51:22Z knoop
[3538]	137	! Comment added
[2716]	138	!
[4182]	139	! Revision 1.1 1997/08/11 06:17:45 raasch
	140	! Initial revision (Testversion)
	141	!
	142	!
[1]	143	! Description:
[2696]	144	! -----------------------------------------------------------------------------!
[1682]	145	!> Creating grid depending constants
[2696]	146	!> @todo: Rearrange topo flag list
	147	!> @todo: reference 3D buildings on top of orography is not tested and may need
	148	!> further improvement for steep slopes
	149	!> @todo: Use more advanced setting of building type at filled holes
[1]	150	!------------------------------------------------------------------------------!
[1682]	151	SUBROUTINE init_grid
[1]	152
[1320]	153	USE arrays_3d, &
[3857]	154	ONLY: dd2zu, ddzu, ddzu_pres, ddzw, dzu, dzw, x, xu, y, yv, zu, zw
[4414]	155
[1353]	156	USE control_parameters, &
[4414]	157	ONLY: constant_flux_layer, dz, dz_max, dz_stretch_factor, &
[3065]	158	dz_stretch_factor_array, dz_stretch_level, dz_stretch_level_end,&
	159	dz_stretch_level_end_index, dz_stretch_level_start_index, &
[3241]	160	dz_stretch_level_start, ibc_uv_b, message_string, &
[4414]	161	number_stretch_level_end, &
	162	number_stretch_level_start, &
	163	ocean_mode, &
	164	psolver, &
	165	symmetry_flag, &
	166	topography, &
	167	use_surface_fluxes
	168
[1320]	169	USE grid_variables, &
[2232]	170	ONLY: ddx, ddx2, ddy, ddy2, dx, dx2, dy, dy2, zu_s_inner, zw_w_inner
[4414]	171
[1320]	172	USE indices, &
[4414]	173	ONLY: nbgp, &
	174	nx, &
	175	nxl, &
	176	nxlg, &
	177	nxr, &
	178	nxrg, &
	179	ny, &
	180	nyn, &
	181	nyng, &
	182	nys, &
	183	nysg, &
	184	nz, &
	185	nzb, &
	186	nzb_diff, &
	187	nzb_max, &
	188	nzt, &
	189	topo_top_ind, &
	190	topo_min_level
	191
[1320]	192	USE kinds
[2696]	193
[1]	194	USE pegrid
	195
	196	IMPLICIT NONE
	197
[3182]	198	INTEGER(iwp) :: i !< index variable along x
	199	INTEGER(iwp) :: j !< index variable along y
	200	INTEGER(iwp) :: k !< index variable along z
	201	INTEGER(iwp) :: k_top !< topography top index on local PE
	202	INTEGER(iwp) :: n !< loop variable for stretching
	203	INTEGER(iwp) :: number_dz !< number of user-specified dz values
	204	INTEGER(iwp) :: nzb_local_max !< vertical grid index of maximum topography height
	205	INTEGER(iwp) :: nzb_local_min !< vertical grid index of minimum topography height
[1]	206
[2696]	207	INTEGER(iwp), DIMENSION(:,:,:), ALLOCATABLE :: topo !< input array for 3D topography and dummy array for setting "outer"-flags
[2232]	208
[3065]	209	REAL(wp) :: dz_level_end !< distance between calculated height level for u/v-grid and user-specified end level for stretching
[1886]	210	REAL(wp) :: dz_stretched !< stretched vertical grid spacing
[3065]	211
	212	REAL(wp), DIMENSION(:), ALLOCATABLE :: min_dz_stretch_level_end !< Array that contains all minimum heights where the stretching can end
[861]	213
[1]	214
	215	!
[709]	216	!-- Calculation of horizontal array bounds including ghost layers
[667]	217	nxlg = nxl - nbgp
	218	nxrg = nxr + nbgp
	219	nysg = nys - nbgp
	220	nyng = nyn + nbgp
[709]	221
[667]	222	!
[1]	223	!-- Allocate grid arrays
[4386]	224	ALLOCATE( x(0:nx) )
	225	ALLOCATE( xu(0:nx) )
	226
[3857]	227	DO i = 0, nx
	228	xu(i) = i * dx
	229	x(i) = i * dx + 0.5_wp * dx
	230	ENDDO
	231
[4386]	232	ALLOCATE( y(0:ny) )
	233	ALLOCATE( yv(0:ny) )
	234
[3857]	235	DO j = 0, ny
	236	yv(j) = j * dy
	237	y(j) = j * dy + 0.5_wp * dy
	238	ENDDO
	239
[4386]	240	ALLOCATE( ddzu(1:nzt+1) )
	241	ALLOCATE( ddzw(1:nzt+1) )
	242	ALLOCATE( dd2zu(1:nzt) )
	243	ALLOCATE( dzu(1:nzt+1) )
	244	ALLOCATE( dzw(1:nzt+1) )
	245	ALLOCATE( zu(nzb:nzt+1) )
	246	ALLOCATE( zw(nzb:nzt+1) )
[1]	247
	248	!
[4386]	249	!-- For constructing an appropriate grid, the vertical grid spacing dz has to
	250	!-- be specified with a non-negative value in the parameter file
[3065]	251	IF ( dz(1) == -1.0_wp ) THEN
[254]	252	message_string = 'missing dz'
	253	CALL message( 'init_grid', 'PA0200', 1, 2, 0, 6, 0 )
[3065]	254	ELSEIF ( dz(1) <= 0.0_wp ) THEN
	255	WRITE( message_string, * ) 'dz=',dz(1),' <= 0.0'
[254]	256	CALL message( 'init_grid', 'PA0201', 1, 2, 0, 6, 0 )
[1]	257	ENDIF
[94]	258
[1]	259	!
[3065]	260	!-- Initialize dz_stretch_level_start with the value of dz_stretch_level
	261	!-- if it was set by the user
	262	IF ( dz_stretch_level /= -9999999.9_wp ) THEN
	263	dz_stretch_level_start(1) = dz_stretch_level
	264	ENDIF
	265
	266	!
	267	!-- Determine number of dz values and stretching levels specified by the
	268	!-- user to allow right controlling of the stretching mechanism and to
[3139]	269	!-- perform error checks. The additional requirement that dz /= dz_max
	270	!-- for counting number of user-specified dz values is necessary. Otherwise
	271	!-- restarts would abort if the old stretching mechanism with dz_stretch_level
	272	!-- is used (Attention: The user is not allowed to specify a dz value equal
	273	!-- to the default of dz_max = 999.0).
	274	number_dz = COUNT( dz /= -1.0_wp .AND. dz /= dz_max)
[3065]	275	number_stretch_level_start = COUNT( dz_stretch_level_start /= &
	276	-9999999.9_wp )
	277	number_stretch_level_end = COUNT( dz_stretch_level_end /= &
	278	9999999.9_wp )
	279
	280	!
[4386]	281	!-- The number of specified end levels +1 has to be the same as the number
[3065]	282	!-- of specified dz values
	283	IF ( number_dz /= number_stretch_level_end + 1 ) THEN
[4386]	284	WRITE( message_string, * ) 'The number of values for dz = ', &
	285	number_dz, 'has to be the same as& ', &
	286	'the number of values for ', &
	287	'dz_stretch_level_end + 1 = ', &
[3065]	288	number_stretch_level_end+1
[4601]	289	CALL message( 'init_grid', 'PA0156', 1, 2, 0, 6, 0 )
[3065]	290	ENDIF
	291
	292	!
[4386]	293	!-- The number of specified start levels has to be the same or one less than
	294	!-- the number of specified dz values
	295	IF ( number_dz /= number_stretch_level_start + 1 .AND. &
[3065]	296	number_dz /= number_stretch_level_start ) THEN
[4386]	297	WRITE( message_string, * ) 'The number of values for dz = ', &
	298	number_dz, 'has to be the same as or one ', &
	299	'more than& the number of values for ', &
	300	'dz_stretch_level_start = ', &
[3065]	301	number_stretch_level_start
[4601]	302	CALL message( 'init_grid', 'PA0211', 1, 2, 0, 6, 0 )
[3065]	303	ENDIF
	304
[4386]	305	!-- The number of specified start levels has to be the same or one more than
	306	!-- the number of specified end levels
	307	IF ( number_stretch_level_start /= number_stretch_level_end + 1 .AND. &
[3065]	308	number_stretch_level_start /= number_stretch_level_end ) THEN
[4386]	309	WRITE( message_string, * ) 'The number of values for ', &
	310	'dz_stretch_level_start = ', &
	311	dz_stretch_level_start, 'has to be the ', &
	312	'same or one more than& the number of ', &
	313	'values for dz_stretch_level_end = ', &
[3065]	314	number_stretch_level_end
[4601]	315	CALL message( 'init_grid', 'PA0216', 1, 2, 0, 6, 0 )
[3065]	316	ENDIF
	317
	318	!
	319	!-- Initialize dz for the free atmosphere with the value of dz_max
	320	IF ( dz(number_stretch_level_start+1) == -1.0_wp .AND. &
	321	number_stretch_level_start /= 0 ) THEN
	322	dz(number_stretch_level_start+1) = dz_max
	323	ENDIF
	324
	325	!
	326	!-- Initialize the stretching factor if (infinitely) stretching in the free
	327	!-- atmosphere is desired (dz_stretch_level_end was not specified for the
	328	!-- free atmosphere)
	329	IF ( number_stretch_level_start == number_stretch_level_end + 1 ) THEN
	330	dz_stretch_factor_array(number_stretch_level_start) = &
	331	dz_stretch_factor
	332	ENDIF
	333
	334	!
	335	!-- Allocation of arrays for stretching
	336	ALLOCATE( min_dz_stretch_level_end(number_stretch_level_start) )
[3066]	337
[3065]	338	!
[4386]	339	!-- Define the vertical grid levels. Start with atmosphere branch
[3294]	340	IF ( .NOT. ocean_mode ) THEN
[3065]	341
[94]	342	!
[3065]	343	!-- The stretching region has to be large enough to allow for a smooth
[4386]	344	!-- transition between two different grid spacings. The number 4 is an
	345	!-- empirical value
[3065]	346	DO n = 1, number_stretch_level_start
	347	min_dz_stretch_level_end(n) = dz_stretch_level_start(n) + &
	348	4 * MAX( dz(n),dz(n+1) )
	349	ENDDO
	350
[3066]	351	IF ( ANY( min_dz_stretch_level_end(1:number_stretch_level_start) > &
	352	dz_stretch_level_end(1:number_stretch_level_start) ) ) THEN
[4601]	353	message_string= 'Each dz_stretch_level_end has to be larger ' // &
	354	'than its corresponding value for &' // &
	355	'dz_stretch_level_start + 4*MAX(dz(n),dz(n+1)) '// &
	356	'to allow for smooth grid stretching'
	357	CALL message( 'init_grid', 'PA0224', 1, 2, 0, 6, 0 )
[3065]	358	ENDIF
	359
	360	!
[4386]	361	!-- Stretching must not be applied within the surface layer
[3065]	362	!-- (first two grid points). For the default case dz_stretch_level_start
	363	!-- is negative. Therefore the absolut value is checked here.
[4386]	364	IF ( ANY( ABS( dz_stretch_level_start ) <= dz(1) * 1.5_wp ) ) THEN
	365	WRITE( message_string, * ) 'Each dz_stretch_level_start has to be ',&
[3065]	366	'larger than ', dz(1) * 1.5
[4601]	367	CALL message( 'init_grid', 'PA0226', 1, 2, 0, 6, 0 )
[3065]	368	ENDIF
	369
	370	!
	371	!-- The stretching has to start and end on a grid level. Therefore
[4386]	372	!-- user-specified values are mapped to the next lowest level. The
	373	!-- calculation of the first level is realized differently just because of
	374	!-- historical reasons (the advanced/new stretching mechanism was realized
	375	!-- in a way that results don't change if the old parameters
	376	!-- dz_stretch_level, dz_stretch_factor and dz_max are used)
[3065]	377	IF ( number_stretch_level_start /= 0 ) THEN
	378	dz_stretch_level_start(1) = INT( (dz_stretch_level_start(1) - &
	379	dz(1)/2.0) / dz(1) ) &
	380	* dz(1) + dz(1)/2.0
	381	ENDIF
	382
	383	IF ( number_stretch_level_start > 1 ) THEN
	384	DO n = 2, number_stretch_level_start
	385	dz_stretch_level_start(n) = INT( dz_stretch_level_start(n) / &
	386	dz(n) ) * dz(n)
	387	ENDDO
	388	ENDIF
	389
	390	IF ( number_stretch_level_end /= 0 ) THEN
	391	DO n = 1, number_stretch_level_end
	392	dz_stretch_level_end(n) = INT( dz_stretch_level_end(n) / &
	393	dz(n+1) ) * dz(n+1)
	394	ENDDO
	395	ENDIF
[4386]	396
[3065]	397	!
	398	!-- Determine stretching factor if necessary
	399	IF ( number_stretch_level_end >= 1 ) THEN
	400	CALL calculate_stretching_factor( number_stretch_level_end )
	401	ENDIF
	402
	403	!
[94]	404	!-- Grid for atmosphere with surface at z=0 (k=0, w-grid).
[3065]	405	!-- First compute the u- and v-levels. In case of dirichlet bc for u and v
	406	!-- the first u/v- and w-level (k=0) are defined at same height (z=0).
[843]	407	!-- The second u-level (k=1) corresponds to the top of the
[4386]	408	!-- surface layer. In case of symmetric boundaries (closed channel flow),
[4340]	409	!-- the first grid point is always at z=0.
	410	IF ( ibc_uv_b == 0 .OR. ibc_uv_b == 2 .OR. &
	411	topography == 'closed_channel' ) THEN
[1353]	412	zu(0) = 0.0_wp
[667]	413	ELSE
[3065]	414	zu(0) = - dz(1) * 0.5_wp
[667]	415	ENDIF
[3065]	416
	417	zu(1) = dz(1) * 0.5_wp
	418
	419	!
	420	!-- Determine u and v height levels considering the possibility of grid
	421	!-- stretching in several heights.
	422	n = 1
	423	dz_stretch_level_start_index = nzt+1
	424	dz_stretch_level_end_index = nzt+1
	425	dz_stretched = dz(1)
[1]	426
[3065]	427	!-- The default value of dz_stretch_level_start is negative, thus the first
[4386]	428	!-- condition is true even if no stretching shall be applied. Hence, the
	429	!-- second condition is also necessary.
[4340]	430	DO k = 2, nzt+1-symmetry_flag
[3065]	431	IF ( dz_stretch_level_start(n) <= zu(k-1) .AND. &
	432	dz_stretch_level_start(n) /= -9999999.9_wp ) THEN
	433	dz_stretched = dz_stretched * dz_stretch_factor_array(n)
	434
	435	IF ( dz(n) > dz(n+1) ) THEN
	436	dz_stretched = MAX( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (higher) dz
	437	ELSE
	438	dz_stretched = MIN( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (lower) dz
	439	ENDIF
	440
	441	IF ( dz_stretch_level_start_index(n) == nzt+1 ) &
	442	dz_stretch_level_start_index(n) = k-1
	443
[94]	444	ENDIF
[3065]	445
[94]	446	zu(k) = zu(k-1) + dz_stretched
[3065]	447
	448	!
	449	!-- Make sure that the stretching ends exactly at dz_stretch_level_end
	450	dz_level_end = ABS( zu(k) - dz_stretch_level_end(n) )
	451
	452	IF ( dz_level_end < dz(n+1)/3.0 ) THEN
	453	zu(k) = dz_stretch_level_end(n)
	454	dz_stretched = dz(n+1)
	455	dz_stretch_level_end_index(n) = k
	456	n = n + 1
	457	ENDIF
[94]	458	ENDDO
[4340]	459
	460	!
	461	!-- If a closed channel flow is simulated, make sure that grid structure is
	462	!-- the same for both bottom and top boundary. (Hint: Using a different dz
	463	!-- at the bottom and at the top makes no sense due to symmetric boundaries
	464	!-- where dz should be equal. Therefore, different dz at the bottom and top
	465	!-- causes an abort (see check_parameters).)
	466	IF ( topography == 'closed_channel' ) THEN
	467	zu(nzt+1) = zu(nzt) + dz(1) * 0.5_wp
	468	ENDIF
[1]	469
	470	!
[94]	471	!-- Compute the w-levels. They are always staggered half-way between the
[843]	472	!-- corresponding u-levels. In case of dirichlet bc for u and v at the
	473	!-- ground the first u- and w-level (k=0) are defined at same height (z=0).
[4340]	474	!-- Per default, the top w-level is extrapolated linearly. In case of
	475	!-- a closed channel flow, zu(nzt+1) and zw(nzt) must be set explicitely.
	476	!-- (Hint: Using a different dz at the bottom and at the top makes no sense
	477	!-- due to symmetric boundaries where dz should be equal. Therefore,
	478	!-- different dz at the bottom and top causes an abort (see
	479	!-- check_parameters).)
[1353]	480	zw(0) = 0.0_wp
[4340]	481	DO k = 1, nzt-symmetry_flag
[1353]	482	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	483	ENDDO
[4340]	484	IF ( topography == 'closed_channel' ) THEN
	485	zw(nzt) = zw(nzt-1) + dz(1)
	486	zw(nzt+1) = zw(nzt) + dz(1)
	487	ELSE
	488	zw(nzt+1) = zw(nzt) + 2.0_wp * ( zu(nzt+1) - zw(nzt) )
	489	ENDIF
[1]	490
[4386]	491	ELSE !ocean branch
[3065]	492
[1]	493	!
[3065]	494	!-- The stretching region has to be large enough to allow for a smooth
[4386]	495	!-- transition between two different grid spacings. The number 4 is an
	496	!-- empirical value
[3065]	497	DO n = 1, number_stretch_level_start
	498	min_dz_stretch_level_end(n) = dz_stretch_level_start(n) - &
	499	4 * MAX( dz(n),dz(n+1) )
	500	ENDDO
	501
[3066]	502	IF ( ANY( min_dz_stretch_level_end (1:number_stretch_level_start) < &
	503	dz_stretch_level_end(1:number_stretch_level_start) ) ) THEN
[4386]	504	message_string= 'Each dz_stretch_level_end has to be less ' // &
[3065]	505	'than its corresponding value for &' // &
	506	'dz_stretch_level_start - 4*MAX(dz(n),dz(n+1)) '//&
	507	'to allow for smooth grid stretching'
	508	CALL message( 'init_grid', 'PA0224', 1, 2, 0, 6, 0 )
	509	ENDIF
	510
	511	!
[3068]	512	!-- Stretching must not be applied close to the surface (last two grid
	513	!-- points). For the default case dz_stretch_level_start is negative.
[4386]	514	IF ( ANY( dz_stretch_level_start >= - dz(1) * 1.5_wp ) ) THEN
	515	WRITE( message_string, * ) 'Each dz_stretch_level_start has to be ',&
	516	'less than ', -dz(1) * 1.5
[3065]	517	CALL message( 'init_grid', 'PA0226', 1, 2, 0, 6, 0 )
	518	ENDIF
	519
	520	!
	521	!-- The stretching has to start and end on a grid level. Therefore
[4386]	522	!-- user-specified values are mapped to the next highest level. The
	523	!-- calculation of the first level is realized differently just because of
	524	!-- historical reasons (the advanced/new stretching mechanism was realized
	525	!-- in a way that results don't change if the old parameters
	526	!-- dz_stretch_level, dz_stretch_factor and dz_max are used)
[3065]	527	IF ( number_stretch_level_start /= 0 ) THEN
	528	dz_stretch_level_start(1) = INT( (dz_stretch_level_start(1) + &
	529	dz(1)/2.0) / dz(1) ) &
	530	* dz(1) - dz(1)/2.0
	531	ENDIF
	532
	533	IF ( number_stretch_level_start > 1 ) THEN
	534	DO n = 2, number_stretch_level_start
	535	dz_stretch_level_start(n) = INT( dz_stretch_level_start(n) / &
	536	dz(n) ) * dz(n)
	537	ENDDO
	538	ENDIF
	539
	540	IF ( number_stretch_level_end /= 0 ) THEN
	541	DO n = 1, number_stretch_level_end
	542	dz_stretch_level_end(n) = INT( dz_stretch_level_end(n) / &
	543	dz(n+1) ) * dz(n+1)
	544	ENDDO
	545	ENDIF
	546
	547	!
	548	!-- Determine stretching factor if necessary
	549	IF ( number_stretch_level_end >= 1 ) THEN
	550	CALL calculate_stretching_factor( number_stretch_level_end )
	551	ENDIF
	552
	553	!
[843]	554	!-- Grid for ocean with free water surface is at k=nzt (w-grid).
	555	!-- In case of neumann bc at the ground the first first u-level (k=0) lies
	556	!-- below the first w-level (k=0). In case of dirichlet bc the first u- and
	557	!-- w-level are defined at same height, but staggered from the second level.
[4386]	558	!-- The second u-level (k=1) corresponds to the top of the surface layer.
[3065]	559	!-- z values are negative starting from z=0 (surface)
	560	zu(nzt+1) = dz(1) * 0.5_wp
	561	zu(nzt) = - dz(1) * 0.5_wp
[94]	562
[3065]	563	!
	564	!-- Determine u and v height levels considering the possibility of grid
	565	!-- stretching in several heights.
	566	n = 1
	567	dz_stretch_level_start_index = 0
	568	dz_stretch_level_end_index = 0
	569	dz_stretched = dz(1)
	570
[94]	571	DO k = nzt-1, 0, -1
[3065]	572
	573	IF ( dz_stretch_level_start(n) >= zu(k+1) ) THEN
	574	dz_stretched = dz_stretched * dz_stretch_factor_array(n)
	575
	576	IF ( dz(n) > dz(n+1) ) THEN
	577	dz_stretched = MAX( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (higher) dz
	578	ELSE
	579	dz_stretched = MIN( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (lower) dz
	580	ENDIF
	581
	582	IF ( dz_stretch_level_start_index(n) == 0 ) &
	583	dz_stretch_level_start_index(n) = k+1
	584
	585	ENDIF
	586
	587	zu(k) = zu(k+1) - dz_stretched
	588
[1418]	589	!
[3065]	590	!-- Make sure that the stretching ends exactly at dz_stretch_level_end
	591	dz_level_end = ABS( zu(k) - dz_stretch_level_end(n) )
	592
	593	IF ( dz_level_end < dz(n+1)/3.0 ) THEN
	594	zu(k) = dz_stretch_level_end(n)
	595	dz_stretched = dz(n+1)
	596	dz_stretch_level_end_index(n) = k
	597	n = n + 1
[94]	598	ENDIF
	599	ENDDO
[3065]	600
[94]	601	!
	602	!-- Compute the w-levels. They are always staggered half-way between the
[843]	603	!-- corresponding u-levels, except in case of dirichlet bc for u and v
	604	!-- at the ground. In this case the first u- and w-level are defined at
	605	!-- same height. The top w-level (nzt+1) is not used but set for
	606	!-- consistency, since w and all scalar variables are defined up tp nzt+1.
[3065]	607	zw(nzt+1) = dz(1)
[1353]	608	zw(nzt) = 0.0_wp
[94]	609	DO k = 0, nzt
[1353]	610	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	611	ENDDO
	612
[843]	613	!
	614	!-- In case of dirichlet bc for u and v the first u- and w-level are defined
	615	!-- at same height.
	616	IF ( ibc_uv_b == 0 ) THEN
	617	zu(0) = zw(0)
	618	ENDIF
	619
[4386]	620	ENDIF !End of defining the vertical grid levels
[94]	621
	622	!
[1]	623	!-- Compute grid lengths.
	624	DO k = 1, nzt+1
	625	dzu(k) = zu(k) - zu(k-1)
[1353]	626	ddzu(k) = 1.0_wp / dzu(k)
[1]	627	dzw(k) = zw(k) - zw(k-1)
[1353]	628	ddzw(k) = 1.0_wp / dzw(k)
[1]	629	ENDDO
	630
	631	DO k = 1, nzt
[1353]	632	dd2zu(k) = 1.0_wp / ( dzu(k) + dzu(k+1) )
[1]	633	ENDDO
[667]	634
	635	!
[709]	636	!-- The FFT- SOR-pressure solvers assume grid spacings of a staggered grid
	637	!-- everywhere. For the actual grid, the grid spacing at the lowest level
	638	!-- is only dz/2, but should be dz. Therefore, an additional array
	639	!-- containing with appropriate grid information is created for these
	640	!-- solvers.
[1575]	641	IF ( psolver(1:9) /= 'multigrid' ) THEN
[667]	642	ALLOCATE( ddzu_pres(1:nzt+1) )
	643	ddzu_pres = ddzu
[864]	644	ddzu_pres(1) = ddzu_pres(2) ! change for lowest level
[1]	645	ENDIF
	646
	647	!
	648	!-- Compute the reciprocal values of the horizontal grid lengths.
[1353]	649	ddx = 1.0_wp / dx
	650	ddy = 1.0_wp / dy
[1]	651	dx2 = dx * dx
	652	dy2 = dy * dy
[1353]	653	ddx2 = 1.0_wp / dx2
	654	ddy2 = 1.0_wp / dy2
[1]	655
	656	!
[2696]	657	!-- Allocate 3D array to set topography
	658	ALLOCATE( topo(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	659	topo = 0
	660	!
[4386]	661	!-- Initialize topography by generic topography or read topography from file.
[2696]	662	CALL init_topo( topo )
	663	!
	664	!-- Set flags to mask topography on the grid.
[4414]	665	CALL set_topo_flags( topo )
[2696]	666
	667	!
	668	!-- Determine the maximum level of topography. It is used for
	669	!-- steering the degradation of order of the applied advection scheme,
[4328]	670	!-- as well in the lpm.
[2696]	671	k_top = 0
	672	DO i = nxl, nxr
	673	DO j = nys, nyn
	674	DO k = nzb, nzt + 1
[4109]	675	k_top = MAX( k_top, MERGE( k, 0, .NOT. BTEST( topo(k,j,i), 0 ) ) )
[2696]	676	ENDDO
	677	ENDDO
[1]	678	ENDDO
[2696]	679	#if defined( __parallel )
[4328]	680	CALL MPI_ALLREDUCE( k_top, nzb_max, 1, MPI_INTEGER, &
[2696]	681	MPI_MAX, comm2d, ierr )
	682	#else
[4328]	683	nzb_max = k_top
[2696]	684	#endif
[1]	685	!
[4328]	686	!-- Increment nzb_max by 1 in order to allow for proper diverengence correction.
	687	!-- Further, in case topography extents up to the model top, limit to nzt.
	688	nzb_max = MIN( nzb_max+1, nzt )
	689	!
[2968]	690	!-- Determine minimum index of topography. Usually, this will be nzb. In case
	691	!-- there is elevated topography, however, the lowest topography will be higher.
	692	!-- This index is e.g. used to calculate mean first-grid point atmosphere
	693	!-- temperature, surface pressure and density, etc. .
	694	topo_min_level = 0
	695	#if defined( __parallel )
[4168]	696	CALL MPI_ALLREDUCE( MINVAL( topo_top_ind(nys:nyn,nxl:nxr,0) ), &
[2968]	697	topo_min_level, 1, MPI_INTEGER, MPI_MIN, comm2d, ierr )
	698	#else
[4168]	699	topo_min_level = MINVAL( topo_top_ind(nys:nyn,nxl:nxr,0) )
[2968]	700	#endif
[3182]	701
[2696]	702	!
[2968]	703	!-- Check topography for consistency with model domain. Therefore, use
	704	!-- maximum and minium topography-top indices. Note, minimum topography top
	705	!-- index is already calculated.
[2696]	706	IF ( TRIM( topography ) /= 'flat' ) THEN
	707	#if defined( __parallel )
[4168]	708	CALL MPI_ALLREDUCE( MAXVAL( topo_top_ind(nys:nyn,nxl:nxr,0) ), &
[3182]	709	nzb_local_max, 1, MPI_INTEGER, MPI_MAX, comm2d, ierr )
[2696]	710	#else
[4168]	711	nzb_local_max = MAXVAL( topo_top_ind(nys:nyn,nxl:nxr,0) )
[2696]	712	#endif
[2968]	713	nzb_local_min = topo_min_level
[2696]	714	!
	715	!-- Consistency checks
	716	IF ( nzb_local_min < 0 .OR. nzb_local_max > nz + 1 ) THEN
	717	WRITE( message_string, * ) 'nzb_local values are outside the', &
[3045]	718	' model domain', &
[3046]	719	'&MINVAL( nzb_local ) = ', nzb_local_min, &
	720	'&MAXVAL( nzb_local ) = ', nzb_local_max
[2696]	721	CALL message( 'init_grid', 'PA0210', 1, 2, 0, 6, 0 )
	722	ENDIF
	723	ENDIF
[1]	724	!
[19]	725	!-- Define vertical gridpoint from (or to) which on the usual finite difference
[1]	726	!-- form (which does not use surface fluxes) is applied
[1691]	727	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[1]	728	nzb_diff = nzb + 2
	729	ELSE
	730	nzb_diff = nzb + 1
	731	ENDIF
	732
[4414]	733	IF ( TRIM( topography ) /= 'flat' ) THEN
[2696]	734	!
[4414]	735	!-- Allocate and set the arrays containing the topography height (for output
	736	!-- reasons only).
	737	IF ( nxr == nx .AND. nyn /= ny ) THEN
	738	ALLOCATE( zu_s_inner(nxl:nxr+1,nys:nyn), &
	739	zw_w_inner(nxl:nxr+1,nys:nyn) )
	740	ELSEIF ( nxr /= nx .AND. nyn == ny ) THEN
	741	ALLOCATE( zu_s_inner(nxl:nxr,nys:nyn+1), &
	742	zw_w_inner(nxl:nxr,nys:nyn+1) )
	743	ELSEIF ( nxr == nx .AND. nyn == ny ) THEN
	744	ALLOCATE( zu_s_inner(nxl:nxr+1,nys:nyn+1), &
	745	zw_w_inner(nxl:nxr+1,nys:nyn+1) )
	746	ELSE
	747	ALLOCATE( zu_s_inner(nxl:nxr,nys:nyn), &
	748	zw_w_inner(nxl:nxr,nys:nyn) )
[2696]	749	ENDIF
[1]	750
[4414]	751	zu_s_inner = 0.0_wp
	752	zw_w_inner = 0.0_wp
[1]	753	!
[4414]	754	!-- Determine local topography height on scalar and w-grid. Note, setting
	755	!-- lateral boundary values is not necessary, realized via wall_flags_static_0
	756	!-- array. Further, please note that loop bounds are different from
	757	!-- nxl to nxr and nys to nyn on south and right model boundary, hence,
	758	!-- use intrinsic lbound and ubound functions to infer array bounds.
	759	DO i = LBOUND(zu_s_inner, 1), UBOUND(zu_s_inner, 1)
	760	DO j = LBOUND(zu_s_inner, 2), UBOUND(zu_s_inner, 2)
[2696]	761	!
[4414]	762	!-- Topography height on scalar grid. Therefore, determine index of
	763	!-- upward-facing surface element on scalar grid.
	764	zu_s_inner(i,j) = zu(topo_top_ind(j,i,0))
[2696]	765	!
[4414]	766	!-- Topography height on w grid. Therefore, determine index of
	767	!-- upward-facing surface element on w grid.
	768	zw_w_inner(i,j) = zw(topo_top_ind(j,i,3))
	769	ENDDO
[2696]	770	ENDDO
	771	ENDIF
[4444]	772
[2696]	773	END SUBROUTINE init_grid
	774
[3065]	775
[2696]	776	! Description:
	777	! -----------------------------------------------------------------------------!
[3065]	778	!> Calculation of the stretching factor through an iterative method. Ideas were
	779	!> taken from the paper "Regional stretched grid generation and its application
	780	!> to the NCAR RegCM (1999)". Normally, no analytic solution exists because the
	781	!> system of equations has two variables (r,l) but four requirements
	782	!> (l=integer, r=[0,88;1,2], Eq(6), Eq(5) starting from index j=1) which
	783	!> results into an overdetermined system.
	784	!------------------------------------------------------------------------------!
	785	SUBROUTINE calculate_stretching_factor( number_end )
	786
	787	USE control_parameters, &
[3241]	788	ONLY: dz, dz_stretch_factor_array, &
[3065]	789	dz_stretch_level_end, dz_stretch_level_start, message_string
	790
	791	USE kinds
	792
	793	IMPLICIT NONE
	794
	795	INTEGER(iwp) :: iterations !< number of iterations until stretch_factor_lower/upper_limit is reached
	796	INTEGER(iwp) :: l_rounded !< after l_rounded grid levels dz(n) is strechted to dz(n+1) with stretch_factor_2
	797	INTEGER(iwp) :: n !< loop variable for stretching
	798
	799	INTEGER(iwp), INTENT(IN) :: number_end !< number of user-specified end levels for stretching
	800
	801	REAL(wp) :: delta_l !< absolute difference between l and l_rounded
	802	REAL(wp) :: delta_stretch_factor !< absolute difference between stretch_factor_1 and stretch_factor_2
	803	REAL(wp) :: delta_total_new !< sum of delta_l and delta_stretch_factor for the next iteration (should be as small as possible)
	804	REAL(wp) :: delta_total_old !< sum of delta_l and delta_stretch_factor for the last iteration
	805	REAL(wp) :: distance !< distance between dz_stretch_level_start and dz_stretch_level_end (stretching region)
	806	REAL(wp) :: l !< value that fulfil Eq. (5) in the paper mentioned above together with stretch_factor_1 exactly
	807	REAL(wp) :: numerator !< numerator of the quotient
	808	REAL(wp) :: stretch_factor_1 !< stretching factor that fulfil Eq. (5) togehter with l exactly
	809	REAL(wp) :: stretch_factor_2 !< stretching factor that fulfil Eq. (6) togehter with l_rounded exactly
	810
[3068]	811	REAL(wp) :: dz_stretch_factor_array_2(9) = 1.08_wp !< Array that contains all stretch_factor_2 that belongs to stretch_factor_1
	812
[4386]	813	REAL(wp), PARAMETER :: stretch_factor_interval = 1.0E-06_wp !< interval for sampling possible stretching factors
	814	REAL(wp), PARAMETER :: stretch_factor_lower_limit = 0.88_wp !< lowest possible stretching factor
	815	REAL(wp), PARAMETER :: stretch_factor_upper_limit = 1.12_wp !< highest possible stretching factor
[3065]	816
	817
[3068]	818	l = 0
	819	DO n = 1, number_end
	820
	821	iterations = 1
[4386]	822	stretch_factor_1 = 1.0_wp
	823	stretch_factor_2 = 1.0_wp
	824	delta_total_old = 1.0_wp
[3065]	825
[4386]	826	!
	827	!-- First branch for stretching from rough to fine
[3068]	828	IF ( dz(n) > dz(n+1) ) THEN
	829	DO WHILE ( stretch_factor_1 >= stretch_factor_lower_limit )
	830
[4386]	831	stretch_factor_1 = 1.0_wp - iterations * stretch_factor_interval
	832	distance = ABS( dz_stretch_level_end(n) - &
	833	dz_stretch_level_start(n) )
	834	numerator = distance*stretch_factor_1/dz(n) + &
[3068]	835	stretch_factor_1 - distance/dz(n)
	836
[4386]	837	IF ( numerator > 0.0_wp ) THEN
	838	l = LOG( numerator ) / LOG( stretch_factor_1 ) - 1.0_wp
[3068]	839	l_rounded = NINT( l )
	840	delta_l = ABS( l_rounded - l ) / l
	841	ENDIF
	842
	843	stretch_factor_2 = EXP( LOG( dz(n+1)/dz(n) ) / (l_rounded) )
	844
[4386]	845	delta_stretch_factor = ABS( stretch_factor_1 - &
	846	stretch_factor_2 ) / &
[3068]	847	stretch_factor_2
	848
	849	delta_total_new = delta_l + delta_stretch_factor
[3065]	850
	851	!
[4386]	852	!-- stretch_factor_1 is taken to guarantee that the stretching
	853	!-- procedure ends as close as possible to dz_stretch_level_end.
	854	!-- stretch_factor_2 would guarantee that the stretched dz(n) is
	855	!-- equal to dz(n+1) after l_rounded grid levels.
[3068]	856	IF (delta_total_new < delta_total_old) THEN
	857	dz_stretch_factor_array(n) = stretch_factor_1
	858	dz_stretch_factor_array_2(n) = stretch_factor_2
	859	delta_total_old = delta_total_new
	860	ENDIF
	861
	862	iterations = iterations + 1
	863
	864	ENDDO
[4386]	865
	866	!
	867	!-- Second branch for stretching from fine to rough
[3068]	868	ELSEIF ( dz(n) < dz(n+1) ) THEN
	869	DO WHILE ( stretch_factor_1 <= stretch_factor_upper_limit )
	870
[4386]	871	stretch_factor_1 = 1.0_wp + iterations * stretch_factor_interval
	872	distance = ABS( dz_stretch_level_end(n) - &
[3068]	873	dz_stretch_level_start(n) )
[4386]	874	numerator = distance*stretch_factor_1/dz(n) + &
[3068]	875	stretch_factor_1 - distance/dz(n)
	876
[4386]	877	l = LOG( numerator ) / LOG( stretch_factor_1 ) - 1.0_wp
[3068]	878	l_rounded = NINT( l )
	879	delta_l = ABS( l_rounded - l ) / l
	880
	881	stretch_factor_2 = EXP( LOG( dz(n+1)/dz(n) ) / (l_rounded) )
[3065]	882
[4386]	883	delta_stretch_factor = ABS( stretch_factor_1 - &
	884	stretch_factor_2 ) / &
[3068]	885	stretch_factor_2
	886
	887	delta_total_new = delta_l + delta_stretch_factor
	888
[3065]	889	!
[4386]	890	!-- stretch_factor_1 is taken to guarantee that the stretching
	891	!-- procedure ends as close as possible to dz_stretch_level_end.
	892	!-- stretch_factor_2 would guarantee that the stretched dz(n) is
	893	!-- equal to dz(n+1) after l_rounded grid levels.
[3068]	894	IF (delta_total_new < delta_total_old) THEN
	895	dz_stretch_factor_array(n) = stretch_factor_1
	896	dz_stretch_factor_array_2(n) = stretch_factor_2
	897	delta_total_old = delta_total_new
	898	ENDIF
[3065]	899
[3068]	900	iterations = iterations + 1
	901	ENDDO
	902
	903	ELSE
	904	message_string= 'Two adjacent values of dz must be different'
	905	CALL message( 'init_grid', 'PA0228', 1, 2, 0, 6, 0 )
	906
	907	ENDIF
	908
	909	!
	910	!-- Check if also the second stretching factor fits into the allowed
	911	!-- interval. If not, print a warning for the user.
	912	IF ( dz_stretch_factor_array_2(n) < stretch_factor_lower_limit .OR. &
	913	dz_stretch_factor_array_2(n) > stretch_factor_upper_limit ) THEN
	914	WRITE( message_string, * ) 'stretch_factor_2 = ', &
	915	dz_stretch_factor_array_2(n), ' which is',&
	916	' responsible for exactly reaching& dz =',&
	917	dz(n+1), 'after a specific amount of', &
	918	' grid levels& exceeds the upper', &
	919	' limit =', stretch_factor_upper_limit, &
	920	' &or lower limit = ', &
	921	stretch_factor_lower_limit
	922	CALL message( 'init_grid', 'PA0499', 0, 1, 0, 6, 0 )
	923
	924	ENDIF
	925	ENDDO
[3065]	926
	927	END SUBROUTINE calculate_stretching_factor
	928
	929
	930	! Description:
	931	! -----------------------------------------------------------------------------!
[2696]	932	!> Set temporary topography flags and reference buildings on top of underlying
	933	!> orography.
	934	!------------------------------------------------------------------------------!
	935	SUBROUTINE process_topography( topo_3d )
	936
	937	USE arrays_3d, &
[2747]	938	ONLY: zu, zw
[2696]	939
	940	USE control_parameters, &
[4507]	941	ONLY: bc_lr_cyc, bc_ns_cyc, ocean_mode
[2696]	942
[4457]	943	USE exchange_horiz_mod, &
	944	ONLY: exchange_horiz_int, exchange_horiz_2d
	945
[2696]	946	USE indices, &
	947	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, &
	948	nzt
	949
	950	USE netcdf_data_input_mod, &
[4507]	951	ONLY: buildings_f, building_id_f, building_type_f, &
	952	init_model, &
	953	input_pids_static, &
[2696]	954	terrain_height_f
	955
	956	USE kinds
	957
	958	USE pegrid
	959
	960	IMPLICIT NONE
	961
[2867]	962	INTEGER(iwp) :: i !< running index along x-direction
	963	INTEGER(iwp) :: j !< running index along y-direction
	964	INTEGER(iwp) :: k !< running index along z-direction with respect to numeric grid
	965	INTEGER(iwp) :: k2 !< running index along z-direction with respect to netcdf grid
	966	INTEGER(iwp) :: nr !< index variable indication maximum terrain height for respective building ID
	967	INTEGER(iwp) :: num_build !< counter for number of buildings
	968	INTEGER(iwp) :: topo_top_index !< orography top index, used to map 3D buildings onto terrain
[2696]	969
[4444]	970	#if defined( __parallel )
[2696]	971	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: displace_dum !< displacements of start addresses, used for MPI_ALLGATHERV
[4444]	972	#endif
[2696]	973	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids !< building IDs on entire model domain
	974	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_final !< building IDs on entire model domain, multiple occurences are sorted out
	975	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_final_tmp !< temporary array used for resizing
	976	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_l !< building IDs on local subdomain
	977	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_l_tmp !< temporary array used to resize array of building IDs
	978
	979	INTEGER(iwp), DIMENSION(0:numprocs-1) :: num_buildings !< number of buildings with different ID on entire model domain
	980	INTEGER(iwp), DIMENSION(0:numprocs-1) :: num_buildings_l !< number of buildings with different ID on local subdomain
	981
	982	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo_3d !< input array for 3D topography and dummy array for setting "outer"-flags
	983
	984	REAL(wp) :: ocean_offset !< offset to consider inverse vertical coordinate at topography definition
[3103]	985	REAL(wp) :: oro_min = 0.0_wp !< minimum terrain height in entire model domain, used to reference terrain to zero
[2696]	986	REAL(wp), DIMENSION(:), ALLOCATABLE :: oro_max !< maximum terrain height occupied by an building with certain id
	987	REAL(wp), DIMENSION(:), ALLOCATABLE :: oro_max_l !< maximum terrain height occupied by an building with certain id, on local subdomain
	988
	989	!
[4507]	990	!-- Reference lowest terrain height to zero. This ensures that first,
	991	!-- non-required gird levels (those which lie entirely below the minimum
	992	!-- orography) are avoided, and second, that also negative orography can be used
	993	!-- within the input file.
	994	!-- Please note, in case of a nested run, the global minimum from all parent and
	995	!-- childs need to be remove to avoid steep edges at the child-domain boundaries.
[3103]	996	IF ( input_pids_static ) THEN
[4159]	997
[3200]	998	#if defined( __parallel )
[3103]	999	CALL MPI_ALLREDUCE( MINVAL( terrain_height_f%var ), oro_min, 1, &
	1000	MPI_REAL, MPI_MIN, MPI_COMM_WORLD, ierr )
[3200]	1001	#else
	1002	oro_min = MINVAL( terrain_height_f%var )
	1003	#endif
[3103]	1004	terrain_height_f%var = terrain_height_f%var - oro_min
[4507]	1005	!
	1006	!-- Update reference height used within output files
	1007	init_model%origin_z = init_model%origin_z + oro_min
	1008
[3103]	1009	ENDIF
	1010
	1011	!
[2696]	1012	!-- In the following, buildings and orography are further preprocessed
	1013	!-- before they are mapped on the LES grid.
	1014	!-- Buildings are mapped on top of the orography by maintaining the roof
	1015	!-- shape of the building. This can be achieved by referencing building on
	1016	!-- top of the maximum terrain height within the area occupied by the
	1017	!-- respective building. As buildings and terrain height are defined PE-wise,
	1018	!-- parallelization of this referencing is required (a building can be
	1019	!-- distributed between different PEs).
	1020	!-- In a first step, determine the number of buildings with different
	1021	!-- building id on each PE. In a next step, all building ids are gathered
	1022	!-- into one array which is present to all PEs. For each building ID,
	1023	!-- the maximum terrain height occupied by the respective building is
	1024	!-- computed and distributed to each PE.
	1025	!-- Finally, for each building id and its respective reference orography,
	1026	!-- builidings are mapped on top.
	1027	!--
	1028	!-- First, pre-set topography flags, bit 1 indicates orography, bit 2
	1029	!-- buildings
	1030	!-- classify the respective surfaces.
	1031	topo_3d = IBSET( topo_3d, 0 )
	1032	topo_3d(nzb,:,:) = IBCLR( topo_3d(nzb,:,:), 0 )
	1033	!
[3051]	1034	!-- In order to map topography on PALM grid also in case of ocean simulations,
	1035	!-- pre-calculate an offset value.
[3294]	1036	ocean_offset = MERGE( zw(0), 0.0_wp, ocean_mode )
[3051]	1037	!
[2696]	1038	!-- Reference buildings on top of orography. This is not necessary
	1039	!-- if topography is read from ASCII file as no distinction between buildings
	1040	!-- and terrain height can be made. Moreover, this is also not necessary if
	1041	!-- urban-surface and land-surface model are used at the same time.
[2897]	1042	IF ( input_pids_static ) THEN
	1043
	1044	IF ( buildings_f%from_file ) THEN
	1045	num_buildings_l = 0
	1046	num_buildings = 0
[2696]	1047	!
[3925]	1048	!-- Allocate at least one element for building ids and give it an inital
	1049	!-- negative value that will be overwritten later. This, however, is
	1050	!-- necessary in case there all IDs in the model domain are fill values.
[2897]	1051	ALLOCATE( build_ids_l(1) )
[3925]	1052	build_ids_l = -1
[2897]	1053	DO i = nxl, nxr
	1054	DO j = nys, nyn
	1055	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1056	IF ( num_buildings_l(myid) > 0 ) THEN
[4144]	1057	IF ( ANY( building_id_f%var(j,i) == build_ids_l ) ) &
[2897]	1058	THEN
	1059	CYCLE
	1060	ELSE
	1061	num_buildings_l(myid) = num_buildings_l(myid) + 1
[2696]	1062	!
	1063	!-- Resize array with different local building ids
	1064	ALLOCATE( build_ids_l_tmp(1:SIZE(build_ids_l)) )
	1065	build_ids_l_tmp = build_ids_l
	1066	DEALLOCATE( build_ids_l )
	1067	ALLOCATE( build_ids_l(1:num_buildings_l(myid)) )
	1068	build_ids_l(1:num_buildings_l(myid)-1) = &
	1069	build_ids_l_tmp(1:num_buildings_l(myid)-1)
	1070	build_ids_l(num_buildings_l(myid)) = building_id_f%var(j,i)
	1071	DEALLOCATE( build_ids_l_tmp )
	1072	ENDIF
	1073	!
[2897]	1074	!-- First occuring building id on PE
	1075	ELSE
	1076	num_buildings_l(myid) = num_buildings_l(myid) + 1
	1077	build_ids_l(1) = building_id_f%var(j,i)
	1078	ENDIF
[2696]	1079	ENDIF
[2897]	1080	ENDDO
[2696]	1081	ENDDO
	1082	!
[2897]	1083	!-- Determine number of different building ids for the entire domain
[2696]	1084	#if defined( __parallel )
[2897]	1085	CALL MPI_ALLREDUCE( num_buildings_l, num_buildings, numprocs, &
	1086	MPI_INTEGER, MPI_SUM, comm2d, ierr )
[2696]	1087	#else
[2897]	1088	num_buildings = num_buildings_l
[2696]	1089	#endif
	1090	!
[2897]	1091	!-- Gather all buildings ids on each PEs.
	1092	!-- First, allocate array encompassing all building ids in model domain.
	1093	ALLOCATE( build_ids(1:SUM(num_buildings)) )
[2696]	1094	#if defined( __parallel )
	1095	!
[2897]	1096	!-- Allocate array for displacements.
	1097	!-- As each PE may has a different number of buildings, so that
	1098	!-- the block sizes send by each PE may not be equal. Hence,
	1099	!-- information about the respective displacement is required, indicating
	1100	!-- the respective adress where each MPI-task writes into the receive
	1101	!-- buffer array
	1102	ALLOCATE( displace_dum(0:numprocs-1) )
	1103	displace_dum(0) = 0
	1104	DO i = 1, numprocs-1
	1105	displace_dum(i) = displace_dum(i-1) + num_buildings(i-1)
	1106	ENDDO
[2696]	1107
[2897]	1108	CALL MPI_ALLGATHERV( build_ids_l(1:num_buildings_l(myid)), &
	1109	num_buildings(myid), &
	1110	MPI_INTEGER, &
	1111	build_ids, &
	1112	num_buildings, &
	1113	displace_dum, &
	1114	MPI_INTEGER, &
	1115	comm2d, ierr )
[2696]	1116
[2897]	1117	DEALLOCATE( displace_dum )
[2696]	1118
	1119	#else
[2897]	1120	build_ids = build_ids_l
[2696]	1121	#endif
	1122
	1123	!
[2897]	1124	!-- Note, in parallel mode building ids can occure mutliple times, as
	1125	!-- each PE has send its own ids. Therefore, sort out building ids which
	1126	!-- appear more than one time.
	1127	num_build = 0
	1128	DO nr = 1, SIZE(build_ids)
[2696]	1129
[2897]	1130	IF ( ALLOCATED(build_ids_final) ) THEN
[4144]	1131	IF ( ANY( build_ids(nr) == build_ids_final ) ) THEN
[2897]	1132	CYCLE
	1133	ELSE
	1134	num_build = num_build + 1
	1135	!
	1136	!-- Resize
	1137	ALLOCATE( build_ids_final_tmp(1:num_build) )
	1138	build_ids_final_tmp(1:num_build-1) = build_ids_final(1:num_build-1)
	1139	DEALLOCATE( build_ids_final )
	1140	ALLOCATE( build_ids_final(1:num_build) )
	1141	build_ids_final(1:num_build-1) = build_ids_final_tmp(1:num_build-1)
	1142	build_ids_final(num_build) = build_ids(nr)
	1143	DEALLOCATE( build_ids_final_tmp )
	1144	ENDIF
[2696]	1145	ELSE
	1146	num_build = num_build + 1
	1147	ALLOCATE( build_ids_final(1:num_build) )
	1148	build_ids_final(num_build) = build_ids(nr)
[2897]	1149	ENDIF
	1150	ENDDO
[2696]	1151
	1152	!
[3051]	1153	!-- Determine maximumum terrain height occupied by the respective
	1154	!-- building and temporalily store on oro_max
[2897]	1155	ALLOCATE( oro_max_l(1:SIZE(build_ids_final)) )
	1156	ALLOCATE( oro_max(1:SIZE(build_ids_final)) )
	1157	oro_max_l = 0.0_wp
[2696]	1158
[2897]	1159	DO nr = 1, SIZE(build_ids_final)
[4159]	1160	oro_max_l(nr) = MAXVAL( &
	1161	MERGE( terrain_height_f%var(nys:nyn,nxl:nxr), &
	1162	0.0_wp, &
	1163	building_id_f%var(nys:nyn,nxl:nxr) == &
[2897]	1164	build_ids_final(nr) ) )
	1165	ENDDO
[2696]	1166
	1167	#if defined( __parallel )
[2897]	1168	IF ( SIZE(build_ids_final) >= 1 ) THEN
[4159]	1169	CALL MPI_ALLREDUCE( oro_max_l, oro_max, SIZE( oro_max ), MPI_REAL,&
[2897]	1170	MPI_MAX, comm2d, ierr )
	1171	ENDIF
[2696]	1172	#else
[2897]	1173	oro_max = oro_max_l
[2696]	1174	#endif
[3051]	1175	!
	1176	!-- Finally, determine discrete grid height of maximum orography occupied
[4159]	1177	!-- by a building. Use all-or-nothing approach, i.e. if terrain
	1178	!-- exceeds the scalar level the grid box is fully terrain and the
	1179	!-- maximum terrain is set to the zw level.
	1180	!-- terrain or
[3051]	1181	oro_max_l = 0.0
	1182	DO nr = 1, SIZE(build_ids_final)
	1183	DO k = nzb, nzt
	1184	IF ( zu(k) - ocean_offset <= oro_max(nr) ) &
[3142]	1185	oro_max_l(nr) = zw(k) - ocean_offset
[3051]	1186	ENDDO
[3142]	1187	oro_max(nr) = oro_max_l(nr)
[3051]	1188	ENDDO
[2897]	1189	ENDIF
[2696]	1190	!
[4245]	1191	!-- Allocate array for storing terrain height under buildings
	1192	IF ( buildings_f%from_file ) THEN
	1193	ALLOCATE( buildings_f%oro_max(nysg:nyng,nxlg:nxrg) )
	1194	buildings_f%oro_max = buildings_f%fill1
	1195	END IF
	1196	!
[2867]	1197	!-- Map orography as well as buildings onto grid.
[2696]	1198	DO i = nxl, nxr
	1199	DO j = nys, nyn
[2867]	1200	topo_top_index = 0
[3142]	1201	!
	1202	!-- Obtain index in global building_id array
	1203	IF ( buildings_f%from_file ) THEN
	1204	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1205	!
	1206	!-- Determine index where maximum terrain height occupied by
	1207	!-- the respective building height is stored.
	1208	nr = MINLOC( ABS( build_ids_final - &
	1209	building_id_f%var(j,i) ), DIM = 1 )
[4245]	1210	!
	1211	!-- Save grid-indexed oro_max
	1212	buildings_f%oro_max(j,i) = oro_max(nr)
[3142]	1213	ENDIF
	1214	ENDIF
[2696]	1215	DO k = nzb, nzt
	1216	!
	1217	!-- In a first step, if grid point is below or equal the given
	1218	!-- terrain height, grid point is flagged to be of type natural.
	1219	!-- Please note, in case there is also a building which is lower
	1220	!-- than the vertical grid spacing, initialization of surface
	1221	!-- attributes will not be correct as given surface information
	1222	!-- will not be in accordance to the classified grid points.
[4159]	1223	!-- Hence, in this case, also a building flag.
[2747]	1224	IF ( zu(k) - ocean_offset <= terrain_height_f%var(j,i) ) THEN
[4189]	1225	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
	1226	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1227	topo_top_index = k ! topo_top_index + 1
[2696]	1228	ENDIF
	1229	!
	1230	!-- Set building grid points. Here, only consider 2D buildings.
	1231	!-- 3D buildings require separate treatment.
[2897]	1232	IF ( buildings_f%from_file .AND. buildings_f%lod == 1 ) THEN
[4159]	1233	!
	1234	!-- Fill-up the terrain to the level of maximum orography
	1235	!-- within the building-covered area.
	1236	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1237	!
	1238	!-- Note, oro_max is always on zw level
	1239	IF ( zu(k) - ocean_offset < oro_max(nr) ) THEN
[2696]	1240	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4159]	1241	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1242	ELSEIF ( zu(k) - ocean_offset <= &
	1243	oro_max(nr) + buildings_f%var_2d(j,i) ) THEN
	1244	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[2696]	1245	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1246	ENDIF
	1247	ENDIF
	1248	ENDIF
	1249	ENDDO
	1250	!
[4159]	1251	!-- Special treatment for non grid-resolved buildings. This case,
	1252	!-- the uppermost terrain grid point is flagged as building as well
	1253	!-- well, even though no building exists at all. However, the
	1254	!-- surface element will be identified as urban-surface and the
	1255	!-- input data provided by the drivers is consistent to the surface
	1256	!-- classification. Else, all non grid-resolved buildings would vanish
	1257	!-- and identified as terrain grid points, which, however, won't be
	1258	!-- consistent with the input data.
	1259	IF ( buildings_f%from_file .AND. buildings_f%lod == 1 ) THEN
	1260	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1261	DO k = nzb, nzt
	1262	IF( zw(k) - ocean_offset == oro_max(nr) ) THEN
	1263	IF ( buildings_f%var_2d(j,i) <= zu(k+1) - zw(k) ) THEN
	1264	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1265	ENDIF
	1266	ENDIF
	1267	ENDDO
	1268	ENDIF
	1269	ENDIF
	1270	!
[2696]	1271	!-- Map 3D buildings onto terrain height.
[2867]	1272	!-- In case of any slopes, map building on top of maximum terrain
	1273	!-- height covered by the building. In other words, extend
	1274	!-- building down to the respective local terrain-surface height.
[2897]	1275	IF ( buildings_f%from_file .AND. buildings_f%lod == 2 ) THEN
[2696]	1276	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1277	!
[3051]	1278	!-- Extend building down to the terrain surface, i.e. fill-up
	1279	!-- surface irregularities below a building. Note, oro_max
	1280	!-- is already a discrete height according to the all-or-nothing
	1281	!-- approach, i.e. grid box is either topography or atmosphere,
	1282	!-- terrain top is defined at upper bound of the grid box.
	1283	!-- Hence, check for zw in this case.
[3115]	1284	!-- Note, do this only for buildings which are surface mounted,
	1285	!-- i.e. building types 1-6. Below bridges, which are represented
	1286	!-- exclusively by building type 7, terrain shape should be
	1287	!-- maintained.
[3855]	1288	IF ( building_type_f%from_file ) THEN
	1289	IF ( building_type_f%var(j,i) /= 7 ) THEN
	1290	DO k = topo_top_index + 1, nzt + 1
[4159]	1291	IF ( zu(k) - ocean_offset <= oro_max(nr) ) THEN
[3855]	1292	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4159]	1293	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
[3855]	1294	ENDIF
	1295	ENDDO
	1296	!
	1297	!-- After surface irregularities are smoothen, determine
	1298	!-- lower start index where building starts.
	1299	DO k = nzb, nzt
[4159]	1300	IF ( zu(k) - ocean_offset <= oro_max(nr) ) &
[3855]	1301	topo_top_index = k
	1302	ENDDO
	1303	ENDIF
[3115]	1304	ENDIF
[3051]	1305	!
	1306	!-- Finally, map building on top.
[2867]	1307	k2 = 0
	1308	DO k = topo_top_index, nzt + 1
[2796]	1309	IF ( k2 <= buildings_f%nz-1 ) THEN
[2696]	1310	IF ( buildings_f%var_3d(k2,j,i) == 1 ) THEN
	1311	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
	1312	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1313	ENDIF
	1314	ENDIF
	1315	k2 = k2 + 1
	1316	ENDDO
	1317	ENDIF
	1318	ENDIF
	1319	ENDDO
	1320	ENDDO
	1321	!
[4265]	1322	!-- Horizontal exchange the oro_max array, which is required to for
	1323	!-- initialization of building-surface properties.
	1324	IF ( ALLOCATED( buildings_f%oro_max ) ) THEN
[4457]	1325	CALL exchange_horiz_2d( buildings_f%oro_max(:,:) )
[4265]	1326	ENDIF
[4245]	1327	!
[2696]	1328	!-- Deallocate temporary arrays required for processing and reading data
	1329	IF ( ALLOCATED( oro_max ) ) DEALLOCATE( oro_max )
	1330	IF ( ALLOCATED( oro_max_l ) ) DEALLOCATE( oro_max_l )
	1331	IF ( ALLOCATED( build_ids_final ) ) DEALLOCATE( build_ids_final )
	1332	!
	1333	!-- Topography input via ASCII format.
	1334	ELSE
[3294]	1335	ocean_offset = MERGE( zw(0), 0.0_wp, ocean_mode )
[4159]	1336	!
	1337	!-- Initialize topography bit 0 (indicates obstacle) everywhere to zero
	1338	!-- and clear all grid points at nzb, where alway a surface is defined.
	1339	!-- Further, set also bit 1 (indicates terrain) at nzb, which is further
	1340	!-- used for masked data output and further processing. Note, in the
	1341	!-- ASCII case no distinction is made between buildings and terrain,
	1342	!-- so that setting of bit 1 and 2 at the same time has no effect.
[2696]	1343	topo_3d = IBSET( topo_3d, 0 )
	1344	topo_3d(nzb,:,:) = IBCLR( topo_3d(nzb,:,:), 0 )
[4159]	1345	topo_3d(nzb,:,:) = IBSET( topo_3d(nzb,:,:), 1 )
[2696]	1346	DO i = nxl, nxr
	1347	DO j = nys, nyn
	1348	DO k = nzb, nzt
[3538]	1349	!
	1350	!-- Flag topography for all grid points which are below
	1351	!-- the local topography height.
[4630]	1352	!-- Note, each topography is flagged as building (bit 2) as well as
	1353	!-- terrain (bit 1) in order to employ urban-surface as well as
	1354	!-- land-surface model.
[2747]	1355	IF ( zu(k) - ocean_offset <= buildings_f%var_2d(j,i) ) THEN
[4189]	1356	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4630]	1357	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 1 )
	1358	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
[2696]	1359	ENDIF
	1360	ENDDO
	1361	ENDDO
	1362	ENDDO
	1363	ENDIF
	1364
	1365	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
	1366
	1367	IF ( .NOT. bc_ns_cyc ) THEN
	1368	IF ( nys == 0 ) topo_3d(:,-1,:) = topo_3d(:,0,:)
	1369	IF ( nyn == ny ) topo_3d(:,ny+1,:) = topo_3d(:,ny,:)
	1370	ENDIF
	1371
	1372	IF ( .NOT. bc_lr_cyc ) THEN
	1373	IF ( nxl == 0 ) topo_3d(:,:,-1) = topo_3d(:,:,0)
	1374	IF ( nxr == nx ) topo_3d(:,:,nx+1) = topo_3d(:,:,nx)
	1375	ENDIF
	1376
	1377	END SUBROUTINE process_topography
	1378
	1379
	1380	! Description:
	1381	! -----------------------------------------------------------------------------!
	1382	!> Filter topography, i.e. fill holes resolved by only one grid point.
	1383	!> Such holes are suspected to lead to velocity blow-ups as continuity
	1384	!> equation on discrete grid cannot be fulfilled in such case.
	1385	!------------------------------------------------------------------------------!
	1386	SUBROUTINE filter_topography( topo_3d )
	1387
	1388	USE control_parameters, &
	1389	ONLY: bc_lr_cyc, bc_ns_cyc, message_string
	1390
[4457]	1391	USE exchange_horiz_mod, &
	1392	ONLY: exchange_horiz_int, exchange_horiz_2d_byte, exchange_horiz_2d_int
	1393
[2696]	1394	USE indices, &
	1395	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, nzt
	1396
	1397	USE netcdf_data_input_mod, &
	1398	ONLY: building_id_f, building_type_f
	1399
	1400	USE pegrid
	1401
	1402	IMPLICIT NONE
	1403
[2893]	1404	LOGICAL :: filled = .FALSE. !< flag indicating if holes were filled
	1405
[2696]	1406	INTEGER(iwp) :: i !< running index along x-direction
	1407	INTEGER(iwp) :: j !< running index along y-direction
	1408	INTEGER(iwp) :: k !< running index along z-direction
	1409	INTEGER(iwp) :: num_hole !< number of holes (in topography) resolved by only one grid point
	1410	INTEGER(iwp) :: num_hole_l !< number of holes (in topography) resolved by only one grid point on local PE
	1411	INTEGER(iwp) :: num_wall !< number of surrounding vertical walls for a single grid point
	1412
[2955]	1413	INTEGER(iwp), DIMENSION(:,:,:), ALLOCATABLE :: topo_tmp !< temporary 3D-topography used to fill holes
	1414	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo_3d !< 3D-topography array merging buildings and orography
[2696]	1415	!
	1416	!-- Before checking for holes, set lateral boundary conditions for
	1417	!-- topography. After hole-filling, boundary conditions must be set again.
	1418	!-- Several iterations are performed, in order to fill holes which might
	1419	!-- emerge by the filling-algorithm itself.
	1420	ALLOCATE( topo_tmp(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	1421	topo_tmp = 0
	1422
	1423	num_hole = 99999
	1424	DO WHILE ( num_hole > 0 )
	1425
	1426	num_hole = 0
	1427	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
[2955]	1428	!
	1429	!-- Exchange also building ID and type. Note, building_type is an one-byte
	1430	!-- variable.
	1431	IF ( building_id_f%from_file ) &
	1432	CALL exchange_horiz_2d_int( building_id_f%var, nys, nyn, nxl, nxr, nbgp )
[3763]	1433	IF ( building_type_f%from_file ) &
	1434	CALL exchange_horiz_2d_byte( building_type_f%var, nys, nyn, nxl, nxr, nbgp )
[2696]	1435
	1436	topo_tmp = topo_3d
	1437	!
	1438	!-- In case of non-cyclic lateral boundaries, assume lateral boundary to be
	1439	!-- a solid wall. Thus, intermediate spaces of one grid point between
	1440	!-- boundary and some topographic structure will be filled.
	1441	IF ( .NOT. bc_ns_cyc ) THEN
	1442	IF ( nys == 0 ) topo_tmp(:,-1,:) = IBCLR( topo_tmp(:,0,:), 0 )
	1443	IF ( nyn == ny ) topo_tmp(:,ny+1,:) = IBCLR( topo_tmp(:,ny,:), 0 )
	1444	ENDIF
	1445
	1446	IF ( .NOT. bc_lr_cyc ) THEN
	1447	IF ( nxl == 0 ) topo_tmp(:,:,-1) = IBCLR( topo_tmp(:,:,0), 0 )
	1448	IF ( nxr == nx ) topo_tmp(:,:,nx+1) = IBCLR( topo_tmp(:,:,nx), 0 )
	1449	ENDIF
	1450
	1451	num_hole_l = 0
	1452	DO i = nxl, nxr
	1453	DO j = nys, nyn
	1454	DO k = nzb+1, nzt
	1455	IF ( BTEST( topo_tmp(k,j,i), 0 ) ) THEN
	1456	num_wall = 0
	1457	IF ( .NOT. BTEST( topo_tmp(k,j-1,i), 0 ) ) &
	1458	num_wall = num_wall + 1
	1459	IF ( .NOT. BTEST( topo_tmp(k,j+1,i), 0 ) ) &
	1460	num_wall = num_wall + 1
	1461	IF ( .NOT. BTEST( topo_tmp(k,j,i-1), 0 ) ) &
	1462	num_wall = num_wall + 1
	1463	IF ( .NOT. BTEST( topo_tmp(k,j,i+1), 0 ) ) &
	1464	num_wall = num_wall + 1
	1465	IF ( .NOT. BTEST( topo_tmp(k-1,j,i), 0 ) ) &
	1466	num_wall = num_wall + 1
	1467	IF ( .NOT. BTEST( topo_tmp(k+1,j,i), 0 ) ) &
	1468	num_wall = num_wall + 1
	1469
	1470	IF ( num_wall >= 4 ) THEN
	1471	num_hole_l = num_hole_l + 1
	1472	!
[4314]	1473	!-- Clear flag 0 and set special flag ( bit 4) to indicate
[2696]	1474	!-- that new topography point is a result of filtering process.
	1475	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4314]	1476	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 4 )
[2696]	1477	!
	1478	!-- If filled grid point is occupied by a building, classify
	1479	!-- it as building grid point.
	1480	IF ( building_type_f%from_file ) THEN
	1481	IF ( building_type_f%var(j,i) /= &
	1482	building_type_f%fill .OR. &
	1483	building_type_f%var(j+1,i) /= &
	1484	building_type_f%fill .OR. &
	1485	building_type_f%var(j-1,i) /= &
	1486	building_type_f%fill .OR. &
	1487	building_type_f%var(j,i+1) /= &
	1488	building_type_f%fill .OR. &
	1489	building_type_f%var(j,i-1) /= &
	1490	building_type_f%fill ) THEN
	1491	!
	1492	!-- Set flag indicating building surfaces
	1493	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1494	!
	1495	!-- Set building_type and ID at this position if not
	1496	!-- already set. This is required for proper
	1497	!-- initialization of urban-surface energy balance
	1498	!-- solver.
	1499	IF ( building_type_f%var(j,i) == &
	1500	building_type_f%fill ) THEN
	1501
	1502	IF ( building_type_f%var(j+1,i) /= &
	1503	building_type_f%fill ) THEN
	1504	building_type_f%var(j,i) = &
	1505	building_type_f%var(j+1,i)
	1506	building_id_f%var(j,i) = &
	1507	building_id_f%var(j+1,i)
	1508	ELSEIF ( building_type_f%var(j-1,i) /= &
	1509	building_type_f%fill ) THEN
	1510	building_type_f%var(j,i) = &
	1511	building_type_f%var(j-1,i)
	1512	building_id_f%var(j,i) = &
	1513	building_id_f%var(j-1,i)
	1514	ELSEIF ( building_type_f%var(j,i+1) /= &
	1515	building_type_f%fill ) THEN
	1516	building_type_f%var(j,i) = &
	1517	building_type_f%var(j,i+1)
	1518	building_id_f%var(j,i) = &
	1519	building_id_f%var(j,i+1)
	1520	ELSEIF ( building_type_f%var(j,i-1) /= &
	1521	building_type_f%fill ) THEN
	1522	building_type_f%var(j,i) = &
	1523	building_type_f%var(j,i-1)
	1524	building_id_f%var(j,i) = &
	1525	building_id_f%var(j,i-1)
	1526	ENDIF
	1527	ENDIF
	1528	ENDIF
	1529	ENDIF
	1530	!
	1531	!-- If filled grid point is already classified as building
	1532	!-- everything is fine, else classify this grid point as
	1533	!-- natural type grid point. This case, values for the
	1534	!-- surface type are already set.
	1535	IF ( .NOT. BTEST( topo_3d(k,j,i), 2 ) ) THEN
	1536	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1537	ENDIF
	1538	ENDIF
	1539	ENDIF
	1540	ENDDO
	1541	ENDDO
	1542	ENDDO
	1543	!
	1544	!-- Count the total number of holes, required for informative message.
	1545	#if defined( __parallel )
	1546	CALL MPI_ALLREDUCE( num_hole_l, num_hole, 1, MPI_INTEGER, MPI_SUM, &
	1547	comm2d, ierr )
	1548	#else
	1549	num_hole = num_hole_l
	1550	#endif
[2893]	1551	IF ( num_hole > 0 .AND. .NOT. filled ) filled = .TRUE.
[2696]	1552
[2893]	1553	ENDDO
[2696]	1554	!
[2893]	1555	!-- Create an informative message if any holes were filled.
	1556	IF ( filled ) THEN
	1557	WRITE( message_string, * ) 'Topography was filtered, i.e. holes ' // &
	1558	'resolved by only one grid point ' // &
	1559	'were filled during initialization.'
	1560	CALL message( 'init_grid', 'PA0430', 0, 0, 0, 6, 0 )
	1561	ENDIF
[2696]	1562
	1563	DEALLOCATE( topo_tmp )
	1564	!
	1565	!-- Finally, exchange topo_3d array again and if necessary set Neumann boundary
	1566	!-- condition in case of non-cyclic lateral boundaries.
	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
[2955]	1578	!
	1579	!-- Exchange building ID and type. Note, building_type is an one-byte variable.
	1580	IF ( building_id_f%from_file ) &
	1581	CALL exchange_horiz_2d_int( building_id_f%var, nys, nyn, nxl, nxr, nbgp )
[3763]	1582	IF ( building_type_f%from_file ) &
	1583	CALL exchange_horiz_2d_byte( building_type_f%var, nys, nyn, nxl, nxr, nbgp )
[2696]	1584
	1585	END SUBROUTINE filter_topography
	1586
	1587
	1588	! Description:
	1589	! -----------------------------------------------------------------------------!
	1590	!> Reads topography information from file or sets generic topography. Moreover,
	1591	!> all topography-relevant topography arrays are initialized, and grid flags
	1592	!> are set.
	1593	!------------------------------------------------------------------------------!
	1594	SUBROUTINE init_topo( topo )
	1595
	1596	USE arrays_3d, &
	1597	ONLY: zw
	1598
	1599	USE control_parameters, &
	1600	ONLY: bc_lr_cyc, bc_ns_cyc, building_height, building_length_x, &
	1601	building_length_y, building_wall_left, building_wall_south, &
	1602	canyon_height, canyon_wall_left, canyon_wall_south, &
	1603	canyon_width_x, canyon_width_y, dp_level_ind_b, dz, &
[3241]	1604	message_string, topography, topography_grid_convention, &
[2696]	1605	tunnel_height, tunnel_length, tunnel_width_x, tunnel_width_y, &
	1606	tunnel_wall_depth
	1607
[4457]	1608	USE exchange_horiz_mod, &
	1609	ONLY: exchange_horiz_int
	1610
[2696]	1611	USE grid_variables, &
	1612	ONLY: dx, dy
	1613
	1614	USE indices, &
	1615	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
	1616	nzb, nzt
	1617
	1618	USE kinds
[4189]	1619
	1620	USE netcdf_data_input_mod, &
	1621	ONLY: buildings_f, terrain_height_f
[2696]	1622
	1623	USE pegrid
	1624
	1625	IMPLICIT NONE
	1626
[4386]	1627	INTEGER(iwp) :: bh !< temporary vertical index of building height
	1628	INTEGER(iwp) :: ngp_bx !< grid point number of building size along x
	1629	INTEGER(iwp) :: ngp_by !< grid point number of building size along y
	1630	INTEGER(iwp) :: index_left_bwall !< index for left building wall
	1631	INTEGER(iwp) :: index_right_bwall !< index for right building wall
	1632	INTEGER(iwp) :: index_north_bwall !< index for north building wall
	1633	INTEGER(iwp) :: index_south_bwall !< index for south building wall
	1634	INTEGER(iwp) :: ch !< temporary vertical index for canyon height
	1635	INTEGER(iwp) :: ngp_cx !< grid point number of canyon size along x
	1636	INTEGER(iwp) :: ngp_cy !< grid point number of canyon size along y
	1637	INTEGER(iwp) :: index_left_cwall !< index for left canyon wall
	1638	INTEGER(iwp) :: index_right_cwall !< index for right canyon wall
	1639	INTEGER(iwp) :: index_north_cwall !< index for north canyon wall
	1640	INTEGER(iwp) :: index_south_cwall !< index for south canyon wall
	1641	INTEGER(iwp) :: i !< index variable along x
	1642	INTEGER(iwp) :: j !< index variable along y
	1643	INTEGER(iwp) :: k !< index variable along z
	1644	INTEGER(iwp) :: hv_in !< heavyside function to model inner tunnel surface
	1645	INTEGER(iwp) :: hv_out !< heavyside function to model outer tunnel surface
	1646	INTEGER(iwp) :: txe_out !< end position of outer tunnel wall in x
	1647	INTEGER(iwp) :: txs_out !< start position of outer tunnel wall in x
	1648	INTEGER(iwp) :: tye_out !< end position of outer tunnel wall in y
	1649	INTEGER(iwp) :: tys_out !< start position of outer tunnel wall in y
	1650	INTEGER(iwp) :: txe_in !< end position of inner tunnel wall in x
	1651	INTEGER(iwp) :: txs_in !< start position of inner tunnel wall in x
	1652	INTEGER(iwp) :: tye_in !< end position of inner tunnel wall in y
	1653	INTEGER(iwp) :: tys_in !< start position of inner tunnel wall in y
	1654	INTEGER(iwp) :: td !< tunnel wall depth
	1655	INTEGER(iwp) :: th !< height of outer tunnel wall
[2696]	1656
	1657	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nzb_local !< index for topography top at cell-center
	1658	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo !< input array for 3D topography and dummy array for setting "outer"-flags
	1659	!
[4189]	1660	!-- Check for correct setting of the namelist parameter topography. If
	1661	!-- topography information is read from file but topography = 'flat',
[4386]	1662	!-- initialization does not work properly.
[4189]	1663	IF ( ( buildings_f%from_file .OR. terrain_height_f%from_file ) .AND. &
	1664	TRIM( topography ) /= 'read_from_file' ) THEN
	1665	message_string = 'If topography information is provided (via ' // &
	1666	'Netcdf or ASCII input) topography = ' // &
	1667	'"read_from_file" is required.'
	1668	CALL message( 'init_grid', 'PA0437', 1, 2, 0, 6, 0 )
	1669	ENDIF
	1670	!
[1]	1671	!-- Set outer and inner index arrays for non-flat topography.
	1672	!-- Here consistency checks concerning domain size and periodicity are
	1673	!-- necessary.
	1674	!-- Within this SELECT CASE structure only nzb_local is initialized
	1675	!-- individually depending on the chosen topography type, all other index
	1676	!-- arrays are initialized further below.
	1677	SELECT CASE ( TRIM( topography ) )
	1678
	1679	CASE ( 'flat' )
[2696]	1680	!
[2232]	1681	!-- Initialilize 3D topography array, used later for initializing flags
[4340]	1682	topo(nzb+1:nzt+1,:,:) = IBSET( topo(nzb+1:nzt+1,:,:), 0 )
	1683
	1684	CASE ( 'closed_channel' )
	1685	!
	1686	!-- Initialilize 3D topography array, used later for initializing flags
	1687	topo(nzb+1:nzt,:,:) = IBSET( topo(nzb+1:nzt,:,:), 0 )
[1]	1688
	1689	CASE ( 'single_building' )
	1690	!
	1691	!-- Single rectangular building, by default centered in the middle of the
	1692	!-- total domain
[4386]	1693	ngp_bx = NINT( building_length_x / dx )
	1694	ngp_by = NINT( building_length_y / dy )
[2232]	1695	bh = MINLOC( ABS( zw - building_height ), 1 ) - 1
	1696	IF ( ABS( zw(bh) - building_height ) == &
[1675]	1697	ABS( zw(bh+1) - building_height ) ) bh = bh + 1
[1322]	1698	IF ( building_wall_left == 9999999.9_wp ) THEN
[4386]	1699	building_wall_left = ( nx + 1 - ngp_bx ) / 2 * dx
[1]	1700	ENDIF
[4386]	1701	index_left_bwall = NINT( building_wall_left / dx )
	1702	index_right_bwall = index_left_bwall + ngp_bx
[1]	1703
[1322]	1704	IF ( building_wall_south == 9999999.9_wp ) THEN
[4386]	1705	building_wall_south = ( ny + 1 - ngp_by ) / 2 * dy
[1]	1706	ENDIF
[4386]	1707	index_south_bwall = NINT( building_wall_south / dy )
	1708	index_north_bwall = index_south_bwall + ngp_by
[1]	1709
	1710	!
	1711	!-- Building size has to meet some requirements
[4386]	1712	IF ( ( index_left_bwall < 1 ) .OR. ( index_right_bwall > nx-1 ) .OR. &
	1713	( index_right_bwall < index_left_bwall+3 ) .OR. &
	1714	( index_south_bwall < 1 ) .OR. ( index_north_bwall > ny-1 ) .OR.&
	1715	( index_north_bwall < index_south_bwall+3 ) ) THEN
[274]	1716	WRITE( message_string, * ) 'inconsistent building parameters:', &
[4386]	1717	'&index_left_bwall=', index_left_bwall, &
	1718	'index_right_bwall=', index_right_bwall, &
	1719	'index_south_bwall=', index_south_bwall, &
	1720	'index_north_bwall=', index_north_bwall, &
	1721	'nx=', nx, 'ny=', ny
[254]	1722	CALL message( 'init_grid', 'PA0203', 1, 2, 0, 6, 0 )
[1]	1723	ENDIF
	1724
[2696]	1725	ALLOCATE( nzb_local(nysg:nyng,nxlg:nxrg) )
[2892]	1726	nzb_local = 0
[1]	1727	!
[1968]	1728	!-- Define the building.
[4386]	1729	IF ( index_left_bwall <= nxr .AND. index_right_bwall >= nxl .AND. &
	1730	index_south_bwall <= nyn .AND. index_north_bwall >= nys ) &
	1731	nzb_local(MAX(nys,index_south_bwall):MIN(nyn,index_north_bwall), &
	1732	MAX(nxl,index_left_bwall):MIN(nxr,index_right_bwall)) = bh
[2232]	1733	!
[2696]	1734	!-- Set bit array on basis of nzb_local
	1735	DO i = nxl, nxr
	1736	DO j = nys, nyn
	1737	topo(nzb_local(j,i)+1:nzt+1,j,i) = &
	1738	IBSET( topo(nzb_local(j,i)+1:nzt+1,j,i), 0 )
[2232]	1739	ENDDO
	1740	ENDDO
[2696]	1741
	1742	DEALLOCATE( nzb_local )
[2232]	1743
[2696]	1744	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	1745	!
	1746	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	1747	!-- boundary conditions for topography.
	1748	IF ( .NOT. bc_ns_cyc ) THEN
	1749	IF ( nys == 0 ) THEN
	1750	DO i = 1, nbgp
	1751	topo(:,nys-i,:) = topo(:,nys,:)
	1752	ENDDO
	1753	ENDIF
	1754	IF ( nyn == ny ) THEN
	1755	DO i = 1, nbgp
	1756	topo(:,nyn+i,:) = topo(:,nyn,:)
	1757	ENDDO
	1758	ENDIF
	1759	ENDIF
	1760	IF ( .NOT. bc_lr_cyc ) THEN
	1761	IF ( nxl == 0 ) THEN
	1762	DO i = 1, nbgp
	1763	topo(:,:,nxl-i) = topo(:,:,nxl)
	1764	ENDDO
	1765	ENDIF
	1766	IF ( nxr == nx ) THEN
	1767	DO i = 1, nbgp
	1768	topo(:,:,nxr+i) = topo(:,:,nxr)
	1769	ENDDO
	1770	ENDIF
	1771	ENDIF
[2232]	1772
[240]	1773	CASE ( 'single_street_canyon' )
	1774	!
	1775	!-- Single quasi-2D street canyon of infinite length in x or y direction.
	1776	!-- The canyon is centered in the other direction by default.
[1322]	1777	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[240]	1778	!
	1779	!-- Street canyon in y direction
[4386]	1780	ngp_cx = NINT( canyon_width_x / dx )
[1322]	1781	IF ( canyon_wall_left == 9999999.9_wp ) THEN
[4386]	1782	canyon_wall_left = ( nx + 1 - ngp_cx ) / 2 * dx
[240]	1783	ENDIF
[4386]	1784	index_left_cwall= NINT( canyon_wall_left / dx )
	1785	index_right_cwall= index_left_cwall+ ngp_cx
[1322]	1786	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[240]	1787	!
	1788	!-- Street canyon in x direction
[4386]	1789	ngp_cy = NINT( canyon_width_y / dy )
[1322]	1790	IF ( canyon_wall_south == 9999999.9_wp ) THEN
[4386]	1791	canyon_wall_south = ( ny + 1 - ngp_cy ) / 2 * dy
[240]	1792	ENDIF
[4386]	1793	index_south_cwall = NINT( canyon_wall_south / dy )
	1794	index_north_cwall = index_south_cwall + ngp_cy
[2696]	1795
[240]	1796	ELSE
[254]	1797
	1798	message_string = 'no street canyon width given'
	1799	CALL message( 'init_grid', 'PA0204', 1, 2, 0, 6, 0 )
	1800
[240]	1801	ENDIF
	1802
[2232]	1803	ch = MINLOC( ABS( zw - canyon_height ), 1 ) - 1
	1804	IF ( ABS( zw(ch) - canyon_height ) == &
[1675]	1805	ABS( zw(ch+1) - canyon_height ) ) ch = ch + 1
[240]	1806	dp_level_ind_b = ch
	1807	!
	1808	!-- Street canyon size has to meet some requirements
[1322]	1809	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[4386]	1810	IF ( ( index_left_cwall< 1 ) .OR. ( index_right_cwall> nx-1 ) .OR.&
[4543]	1811	( ngp_cx < 3 ) ) THEN
[1353]	1812	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
[4386]	1813	'&index_left_cwall=', index_left_cwall, &
	1814	' index_right_cwall=', index_right_cwall, &
	1815	' ngp_cx=', ngp_cx, &
[3045]	1816	' ch=', ch, ' nx=', nx, ' ny=', ny
[254]	1817	CALL message( 'init_grid', 'PA0205', 1, 2, 0, 6, 0 )
[240]	1818	ENDIF
[1322]	1819	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[4386]	1820	IF ( ( index_south_cwall < 1 ) .OR. &
[4543]	1821	( index_north_cwall > ny-1 ) .OR. ( ngp_cy < 3 ) ) THEN
[1353]	1822	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
[4386]	1823	'&index_south_cwall=', index_south_cwall, &
	1824	' index_north_cwall=', index_north_cwall, &
	1825	' ngp_cy=', ngp_cy, &
[3045]	1826	' ch=', ch, ' nx=', nx, ' ny=', ny
[254]	1827	CALL message( 'init_grid', 'PA0206', 1, 2, 0, 6, 0 )
[240]	1828	ENDIF
	1829	ENDIF
[1353]	1830	IF ( canyon_width_x /= 9999999.9_wp .AND. &
	1831	canyon_width_y /= 9999999.9_wp ) THEN
	1832	message_string = 'inconsistent canyon parameters:' // &
[3046]	1833	'&street canyon can only be oriented' // &
[3045]	1834	' either in x- or in y-direction'
[254]	1835	CALL message( 'init_grid', 'PA0207', 1, 2, 0, 6, 0 )
[240]	1836	ENDIF
	1837
[2696]	1838	ALLOCATE( nzb_local(nysg:nyng,nxlg:nxrg) )
[240]	1839	nzb_local = ch
[1322]	1840	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[4386]	1841	IF ( index_left_cwall<= nxr .AND. index_right_cwall>= nxl ) &
	1842	nzb_local(:,MAX(nxl,index_left_cwall+1):MIN(nxr,index_right_cwall-1)) = 0
[1322]	1843	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[4386]	1844	IF ( index_south_cwall <= nyn .AND. index_north_cwall >= nys ) &
	1845	nzb_local(MAX(nys,index_south_cwall+1):MIN(nyn,index_north_cwall-1),:) = 0
[240]	1846	ENDIF
[2232]	1847	!
[2696]	1848	!-- Set bit array on basis of nzb_local
	1849	DO i = nxl, nxr
	1850	DO j = nys, nyn
	1851	topo(nzb_local(j,i)+1:nzt+1,j,i) = &
	1852	IBSET( topo(nzb_local(j,i)+1:nzt+1,j,i), 0 )
[2232]	1853	ENDDO
	1854	ENDDO
[2696]	1855	DEALLOCATE( nzb_local )
[1994]	1856
[2696]	1857	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	1858	!
	1859	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	1860	!-- boundary conditions for topography.
	1861	IF ( .NOT. bc_ns_cyc ) THEN
	1862	IF ( nys == 0 ) THEN
	1863	DO i = 1, nbgp
	1864	topo(:,nys-i,:) = topo(:,nys,:)
	1865	ENDDO
	1866	ENDIF
	1867	IF ( nyn == ny ) THEN
	1868	DO i = 1, nbgp
	1869	topo(:,nyn+i,:) = topo(:,nyn,:)
	1870	ENDDO
	1871	ENDIF
	1872	ENDIF
	1873	IF ( .NOT. bc_lr_cyc ) THEN
	1874	IF ( nxl == 0 ) THEN
	1875	DO i = 1, nbgp
	1876	topo(:,:,nxl-i) = topo(:,:,nxl)
	1877	ENDDO
	1878	ENDIF
	1879	IF ( nxr == nx ) THEN
	1880	DO i = 1, nbgp
	1881	topo(:,:,nxr+i) = topo(:,:,nxr)
	1882	ENDDO
	1883	ENDIF
	1884	ENDIF
[2232]	1885
	1886	CASE ( 'tunnel' )
	1887
	1888	!
	1889	!-- Tunnel height
	1890	IF ( tunnel_height == 9999999.9_wp ) THEN
	1891	th = zw( INT( 0.2 * nz) )
	1892	ELSE
	1893	th = tunnel_height
	1894	ENDIF
	1895	!
	1896	!-- Tunnel-wall depth
[2696]	1897	IF ( tunnel_wall_depth == 9999999.9_wp ) THEN
[3065]	1898	td = MAX ( dx, dy, dz(1) )
[2232]	1899	ELSE
	1900	td = tunnel_wall_depth
	1901	ENDIF
	1902	!
	1903	!-- Check for tunnel width
	1904	IF ( tunnel_width_x == 9999999.9_wp .AND. &
	1905	tunnel_width_y == 9999999.9_wp ) THEN
	1906	message_string = 'No tunnel width is given. '
[2274]	1907	CALL message( 'init_grid', 'PA0280', 1, 2, 0, 6, 0 )
[2232]	1908	ENDIF
	1909	IF ( tunnel_width_x /= 9999999.9_wp .AND. &
	1910	tunnel_width_y /= 9999999.9_wp ) THEN
	1911	message_string = 'Inconsistent tunnel parameters:' // &
	1912	'tunnel can only be oriented' // &
	1913	'either in x- or in y-direction.'
[2274]	1914	CALL message( 'init_grid', 'PA0281', 1, 2, 0, 6, 0 )
[2232]	1915	ENDIF
	1916	!
[4356]	1917	!-- Check for too small tunnel width in x- and y-direction
	1918	IF ( tunnel_width_x /= 9999999.9_wp .AND. &
	1919	tunnel_width_x - 2.0_wp * td <= 2.0_wp * dx ) THEN
	1920	message_string = 'tunnel_width_x too small'
	1921	CALL message( 'init_grid', 'PA0175', 1, 2, 0, 6, 0 )
	1922	ENDIF
	1923	IF ( tunnel_width_y /= 9999999.9_wp .AND. &
	1924	tunnel_width_y - 2.0_wp * td <= 2.0_wp * dy ) THEN
	1925	message_string = 'tunnel_width_y too small'
	1926	CALL message( 'init_grid', 'PA0455', 1, 2, 0, 6, 0 )
	1927	ENDIF
	1928	!
	1929	!-- Check for too large tunnel width.
	1930	!-- Tunnel axis along y.
[2232]	1931	IF ( tunnel_width_x /= 9999999.9_wp ) THEN
	1932	IF ( tunnel_width_x > ( nx + 1 ) * dx ) THEN
[4356]	1933	message_string = 'tunnel_width_x too large'
[2274]	1934	CALL message( 'init_grid', 'PA0282', 1, 2, 0, 6, 0 )
[2232]	1935	ENDIF
	1936
	1937	txs_out = INT( ( nx + 1 ) * 0.5_wp * dx - tunnel_width_x * 0.5_wp )
	1938	txe_out = INT( ( nx + 1 ) * 0.5_wp * dx + tunnel_width_x * 0.5_wp )
	1939	txs_in = INT( ( nx + 1 ) * 0.5_wp * dx - &
	1940	( tunnel_width_x * 0.5_wp - td ) )
	1941	txe_in = INT( ( nx + 1 ) * 0.5_wp * dx + &
[2696]	1942	( tunnel_width_x * 0.5_wp - td ) )
[2232]	1943
	1944	tys_out = INT( ( ny + 1 ) * 0.5_wp * dy - tunnel_length * 0.5_wp )
	1945	tye_out = INT( ( ny + 1 ) * 0.5_wp * dy + tunnel_length * 0.5_wp )
	1946	tys_in = tys_out
	1947	tye_in = tye_out
	1948	ENDIF
	1949	!
[4356]	1950	!-- Tunnel axis along x.
[2232]	1951	IF ( tunnel_width_y /= 9999999.9_wp ) THEN
	1952	IF ( tunnel_width_y > ( ny + 1 ) * dy ) THEN
[4356]	1953	message_string = 'tunnel_width_y too large'
[2274]	1954	CALL message( 'init_grid', 'PA0456', 1, 2, 0, 6, 0 )
[2232]	1955	ENDIF
	1956
	1957	txs_out = INT( ( nx + 1 ) * 0.5_wp * dx - tunnel_length * 0.5_wp )
	1958	txe_out = INT( ( nx + 1 ) * 0.5_wp * dx + tunnel_length * 0.5_wp )
	1959	txs_in = txs_out
	1960	txe_in = txe_out
	1961
	1962	tys_out = INT( ( ny + 1 ) * 0.5_wp * dy - tunnel_width_y * 0.5_wp )
	1963	tye_out = INT( ( ny + 1 ) * 0.5_wp * dy + tunnel_width_y * 0.5_wp )
	1964	tys_in = INT( ( ny + 1 ) * 0.5_wp * dy - &
[2696]	1965	( tunnel_width_y * 0.5_wp - td ) )
[2232]	1966	tye_in = INT( ( ny + 1 ) * 0.5_wp * dy + &
	1967	( tunnel_width_y * 0.5_wp - td ) )
	1968	ENDIF
	1969
[2696]	1970	topo = 0
[2232]	1971	DO i = nxl, nxr
	1972	DO j = nys, nyn
	1973	!
	1974	!-- Use heaviside function to model outer tunnel surface
	1975	hv_out = th * 0.5_wp * &
	1976	( ( SIGN( 1.0_wp, i * dx - txs_out ) + 1.0_wp ) &
	1977	- ( SIGN( 1.0_wp, i * dx - txe_out ) + 1.0_wp ) )
	1978
	1979	hv_out = hv_out * 0.5_wp * &
	1980	( ( SIGN( 1.0_wp, j * dy - tys_out ) + 1.0_wp ) &
	1981	- ( SIGN( 1.0_wp, j * dy - tye_out ) + 1.0_wp ) )
[2696]	1982	!
[2232]	1983	!-- Use heaviside function to model inner tunnel surface
	1984	hv_in = ( th - td ) * 0.5_wp * &
	1985	( ( SIGN( 1.0_wp, i * dx - txs_in ) + 1.0_wp ) &
	1986	- ( SIGN( 1.0_wp, i * dx - txe_in ) + 1.0_wp ) )
	1987
	1988	hv_in = hv_in * 0.5_wp * &
	1989	( ( SIGN( 1.0_wp, j * dy - tys_in ) + 1.0_wp ) &
	1990	- ( SIGN( 1.0_wp, j * dy - tye_in ) + 1.0_wp ) )
	1991	!
	1992	!-- Set flags at x-y-positions without any tunnel surface
	1993	IF ( hv_out - hv_in == 0.0_wp ) THEN
[2696]	1994	topo(nzb+1:nzt+1,j,i) = IBSET( topo(nzb+1:nzt+1,j,i), 0 )
[2232]	1995	!
	1996	!-- Set flags at x-y-positions with tunnel surfaces
	1997	ELSE
	1998	DO k = nzb + 1, nzt + 1
	1999	!
	2000	!-- Inner tunnel
	2001	IF ( hv_out - hv_in == th ) THEN
	2002	IF ( zw(k) <= hv_out ) THEN
[2696]	2003	topo(k,j,i) = IBCLR( topo(k,j,i), 0 )
[2232]	2004	ELSE
[2696]	2005	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2006	ENDIF
	2007	ENDIF
	2008	!
	2009	!-- Lateral tunnel walls
	2010	IF ( hv_out - hv_in == td ) THEN
	2011	IF ( zw(k) <= hv_in ) THEN
[2696]	2012	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2013	ELSEIF ( zw(k) > hv_in .AND. zw(k) <= hv_out ) THEN
[2696]	2014	topo(k,j,i) = IBCLR( topo(k,j,i), 0 )
[2232]	2015	ELSEIF ( zw(k) > hv_out ) THEN
[2696]	2016	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2017	ENDIF
	2018	ENDIF
	2019	ENDDO
	2020	ENDIF
	2021	ENDDO
	2022	ENDDO
	2023
[2696]	2024	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	2025	!
	2026	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	2027	!-- boundary conditions for topography.
	2028	IF ( .NOT. bc_ns_cyc ) THEN
	2029	IF ( nys == 0 ) THEN
	2030	DO i = 1, nbgp
	2031	topo(:,nys-i,:) = topo(:,nys,:)
	2032	ENDDO
	2033	ENDIF
	2034	IF ( nyn == ny ) THEN
	2035	DO i = 1, nbgp
	2036	topo(:,nyn+i,:) = topo(:,nyn,:)
	2037	ENDDO
	2038	ENDIF
	2039	ENDIF
	2040	IF ( .NOT. bc_lr_cyc ) THEN
	2041	IF ( nxl == 0 ) THEN
	2042	DO i = 1, nbgp
	2043	topo(:,:,nxl-i) = topo(:,:,nxl)
	2044	ENDDO
	2045	ENDIF
	2046	IF ( nxr == nx ) THEN
	2047	DO i = 1, nbgp
	2048	topo(:,:,nxr+i) = topo(:,:,nxr)
	2049	ENDDO
	2050	ENDIF
	2051	ENDIF
[2232]	2052
[1]	2053	CASE ( 'read_from_file' )
	2054	!
[2696]	2055	!-- Note, topography information have been already read.
	2056	!-- If required, further process topography, i.e. reference buildings on
	2057	!-- top of orography and set temporary 3D topography array, which is
	2058	!-- used later to set grid flags. Calling of this rouinte is also
	2059	!-- required in case of ASCII input, even though no distinction between
	2060	!-- terrain- and building height is made in this case.
	2061	CALL process_topography( topo )
[1968]	2062	!
[2696]	2063	!-- Filter holes resolved by only one grid-point
	2064	CALL filter_topography( topo )
[1968]	2065	!
[2696]	2066	!-- Exchange ghost-points, as well as add cyclic or Neumann boundary
	2067	!-- conditions.
	2068	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2069	!
[4314]	2070	!-- Set lateral boundary conditions for topography on all ghost layers
[1968]	2071	IF ( .NOT. bc_ns_cyc ) THEN
[2550]	2072	IF ( nys == 0 ) THEN
[2696]	2073	DO i = 1, nbgp
	2074	topo(:,nys-i,:) = topo(:,nys,:)
	2075	ENDDO
[2550]	2076	ENDIF
[2696]	2077	IF ( nyn == ny ) THEN
	2078	DO i = 1, nbgp
	2079	topo(:,nyn+i,:) = topo(:,nyn,:)
	2080	ENDDO
	2081	ENDIF
[1942]	2082	ENDIF
[1910]	2083
[1968]	2084	IF ( .NOT. bc_lr_cyc ) THEN
[2550]	2085	IF ( nxl == 0 ) THEN
[2696]	2086	DO i = 1, nbgp
	2087	topo(:,:,nxl-i) = topo(:,:,nxl)
[2232]	2088	ENDDO
[2696]	2089	ENDIF
	2090	IF ( nxr == nx ) THEN
	2091	DO i = 1, nbgp
	2092	topo(:,:,nxr+i) = topo(:,:,nxr)
	2093	ENDDO
	2094	ENDIF
[2232]	2095	ENDIF
	2096
[667]	2097
[1]	2098	CASE DEFAULT
[2696]	2099	!
[1]	2100	!-- The DEFAULT case is reached either if the parameter topography
[217]	2101	!-- contains a wrong character string or if the user has defined a special
[1]	2102	!-- case in the user interface. There, the subroutine user_init_grid
	2103	!-- checks which of these two conditions applies.
[2696]	2104	CALL user_init_grid( topo )
	2105	CALL filter_topography( topo )
[1]	2106
	2107	END SELECT
	2108	!
	2109	!-- Consistency checks and index array initialization are only required for
[2696]	2110	!-- non-flat topography.
[1]	2111	IF ( TRIM( topography ) /= 'flat' ) THEN
	2112	!
[2232]	2113	!-- In case of non-flat topography, check whether the convention how to
	2114	!-- define the topography grid has been set correctly, or whether the default
	2115	!-- is applicable. If this is not possible, abort.
	2116	IF ( TRIM( topography_grid_convention ) == ' ' ) THEN
[4340]	2117	IF ( TRIM( topography ) /= 'closed_channel' .AND. &
	2118	TRIM( topography ) /= 'single_building' .AND. &
[2232]	2119	TRIM( topography ) /= 'single_street_canyon' .AND. &
	2120	TRIM( topography ) /= 'tunnel' .AND. &
	2121	TRIM( topography ) /= 'read_from_file') THEN
	2122	!-- The default value is not applicable here, because it is only valid
[3045]	2123	!-- for the four standard cases 'single_building',
	2124	!-- 'single_street_canyon', 'tunnel' and 'read_from_file'
[2232]	2125	!-- defined in init_grid.
	2126	WRITE( message_string, * ) &
[2696]	2127	'The value for "topography_grid_convention" ', &
[3046]	2128	'is not set. Its default value is & only valid for ', &
[3045]	2129	'"topography" = ''single_building'', ''tunnel'' ', &
[4340]	2130	'''single_street_canyon'', ''closed_channel'' & or ', &
	2131	'''read_from_file''.', &
[3046]	2132	'& Choose ''cell_edge'' or ''cell_center''.'
[2232]	2133	CALL message( 'init_grid', 'PA0239', 1, 2, 0, 6, 0 )
	2134	ELSE
	2135	!-- The default value is applicable here.
	2136	!-- Set convention according to topography.
	2137	IF ( TRIM( topography ) == 'single_building' .OR. &
	2138	TRIM( topography ) == 'single_street_canyon' ) THEN
	2139	topography_grid_convention = 'cell_edge'
	2140	ELSEIF ( TRIM( topography ) == 'read_from_file' .OR. &
	2141	TRIM( topography ) == 'tunnel') THEN
	2142	topography_grid_convention = 'cell_center'
	2143	ENDIF
	2144	ENDIF
	2145	ELSEIF ( TRIM( topography_grid_convention ) /= 'cell_edge' .AND. &
	2146	TRIM( topography_grid_convention ) /= 'cell_center' ) THEN
	2147	WRITE( message_string, * ) &
[2696]	2148	'The value for "topography_grid_convention" is ', &
[3046]	2149	'not recognized.& Choose ''cell_edge'' or ''cell_center''.'
[2232]	2150	CALL message( 'init_grid', 'PA0240', 1, 2, 0, 6, 0 )
	2151	ENDIF
[1]	2152
[2169]	2153
[217]	2154	IF ( topography_grid_convention == 'cell_edge' ) THEN
[134]	2155	!
[217]	2156	!-- The array nzb_local as defined using the 'cell_edge' convention
	2157	!-- describes the actual total size of topography which is defined at the
	2158	!-- cell edges where u=0 on the topography walls in x-direction and v=0
	2159	!-- on the topography walls in y-direction. However, PALM uses individual
	2160	!-- arrays nzb_u\|v\|w\|s_inner\|outer that are based on nzb_s_inner.
	2161	!-- Therefore, the extent of topography in nzb_local is now reduced by
	2162	!-- 1dx at the E topography walls and by 1dy at the N topography walls
[1968]	2163	!-- to form the basis for nzb_s_inner.
	2164	!-- Note, the reverse memory access (i-j instead of j-i) is absolutely
	2165	!-- required at this point.
	2166	DO j = nys+1, nyn+1
	2167	DO i = nxl-1, nxr
[2232]	2168	DO k = nzb, nzt+1
[2696]	2169	IF ( BTEST( topo(k,j,i), 0 ) .OR. &
	2170	BTEST( topo(k,j,i+1), 0 ) ) &
	2171	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2172	ENDDO
	2173	ENDDO
	2174	ENDDO
[2696]	2175	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2176
	2177	DO i = nxl, nxr+1
	2178	DO j = nys-1, nyn
	2179	DO k = nzb, nzt+1
[2696]	2180	IF ( BTEST( topo(k,j,i), 0 ) .OR. &
	2181	BTEST( topo(k,j+1,i), 0 ) ) &
	2182	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2183	ENDDO
	2184	ENDDO
	2185	ENDDO
[2696]	2186	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2187
[217]	2188	ENDIF
[2696]	2189	ENDIF
[2232]	2190
[1]	2191
[2696]	2192	END SUBROUTINE init_topo
[1]	2193
[2696]	2194	SUBROUTINE set_topo_flags(topo)
[1]	2195
[2696]	2196	USE control_parameters, &
[4294]	2197	ONLY: bc_lr_cyc, bc_ns_cyc, constant_flux_layer, &
	2198	scalar_advec, topography, use_surface_fluxes, use_top_fluxes
[1]	2199
[4457]	2200	USE exchange_horiz_mod, &
	2201	ONLY: exchange_horiz_int
	2202
[2696]	2203	USE indices, &
[3241]	2204	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, &
[4346]	2205	nzt, topo_top_ind, wall_flags_static_0, wall_flags_total_0
[1]	2206
[2696]	2207	USE kinds
[1]	2208
[2696]	2209	IMPLICIT NONE
[1804]	2210
[2696]	2211	INTEGER(iwp) :: i !< index variable along x
[4168]	2212	INTEGER(iwp) :: ibit !< integer bit position of topgraphy masking array
[2696]	2213	INTEGER(iwp) :: j !< index variable along y
	2214	INTEGER(iwp) :: k !< index variable along z
[1]	2215
[2696]	2216	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo !< input array for 3D topography and dummy array for setting "outer"-flags
[2232]	2217
[4329]	2218	ALLOCATE( wall_flags_static_0(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	2219	wall_flags_static_0 = 0
[2232]	2220	!
[2696]	2221	!-- Set-up topography flags. First, set flags only for s, u, v and w-grid.
	2222	!-- Further special flags will be set in following loops.
[2232]	2223	DO i = nxl, nxr
	2224	DO j = nys, nyn
	2225	DO k = nzb, nzt+1
	2226	!
	2227	!-- scalar grid
[4340]	2228	IF ( BTEST( topo(k,j,i), 0 ) ) &
[4329]	2229	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 0 )
[2232]	2230	!
[2696]	2231	!-- u grid
[4340]	2232	IF ( BTEST( topo(k,j,i), 0 ) .AND. &
	2233	BTEST( topo(k,j,i-1), 0 ) ) &
[4329]	2234	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 1 )
[2696]	2235	!
[2232]	2236	!-- v grid
[4340]	2237	IF ( BTEST( topo(k,j,i), 0 ) .AND. &
	2238	BTEST( topo(k,j-1,i), 0 ) ) &
[4329]	2239	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 2 )
[2696]	2240
[2232]	2241	ENDDO
[1]	2242
[2232]	2243	DO k = nzb, nzt
[1]	2244	!
[2232]	2245	!-- w grid
[4340]	2246	IF ( BTEST( topo(k,j,i), 0 ) .AND. &
	2247	BTEST( topo(k+1,j,i), 0 ) ) &
[4329]	2248	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 3 )
[2232]	2249	ENDDO
[4340]	2250
	2251	IF ( topography /= 'closed_channel' ) THEN
	2252	wall_flags_static_0(nzt+1,j,i) = IBSET( wall_flags_static_0(nzt+1,j,i), 3 )
	2253	ENDIF
[2232]	2254
	2255	ENDDO
	2256	ENDDO
[2696]	2257
[4329]	2258	CALL exchange_horiz_int( wall_flags_static_0, nys, nyn, nxl, nxr, nzt, nbgp )
[4346]	2259
[1]	2260	!
[4115]	2261	!-- Set outer array for scalars to mask near-surface grid points. Note, on
	2262	!-- basis of flag 24 futher flags will be derived which are used to control
	2263	!-- production of subgrid TKE production near walls.
[4346]	2264
	2265	ALLOCATE( wall_flags_total_0(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	2266	wall_flags_total_0 = 0
	2267
[2696]	2268	DO i = nxl, nxr
	2269	DO j = nys, nyn
[2232]	2270	DO k = nzb, nzt+1
[4346]	2271	wall_flags_total_0(k,j,i) = IOR( wall_flags_total_0(k,j,i), wall_flags_static_0(k,j,i) )
[2232]	2272	ENDDO
	2273	ENDDO
	2274	ENDDO
[4346]	2275
	2276	CALL exchange_horiz_int( wall_flags_total_0, nys, nyn, nxl, nxr, nzt, nbgp )
	2277
	2278	DO i = nxl, nxr
	2279	DO j = nys, nyn
	2280	DO k = nzb, nzt+1
	2281	IF ( BTEST( wall_flags_total_0(k,j-1,i), 0 ) .AND. &
	2282	BTEST( wall_flags_total_0(k,j+1,i), 0 ) .AND. &
	2283	BTEST( wall_flags_total_0(k,j,i-1), 0 ) .AND. &
	2284	BTEST( wall_flags_total_0(k,j,i+1), 0 ) .AND. &
	2285	BTEST( wall_flags_total_0(k,j-1,i-1), 0 ) .AND. &
	2286	BTEST( wall_flags_total_0(k,j+1,i-1), 0 ) .AND. &
	2287	BTEST( wall_flags_total_0(k,j-1,i+1), 0 ) .AND. &
	2288	BTEST( wall_flags_total_0(k,j+1,i+1), 0 ) ) &
	2289	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 24 )
	2290	ENDDO
	2291	ENDDO
	2292	ENDDO
[1]	2293	!
[2232]	2294	!-- Set further special flags
	2295	DO i = nxl, nxr
	2296	DO j = nys, nyn
	2297	DO k = nzb, nzt+1
[1]	2298	!
[2232]	2299	!-- scalar grid, former nzb_diff_s_inner.
	2300	!-- Note, use this flag also to mask topography in diffusion_u and
	2301	!-- diffusion_v along the vertical direction. In case of
	2302	!-- use_surface_fluxes, fluxes are calculated via MOST, else, simple
	2303	!-- gradient approach is applied. Please note, in case of u- and v-
	2304	!-- diffuison, a small error is made at edges (on the east side for u,
	2305	!-- at the north side for v), since topography on scalar grid point
	2306	!-- is used instead of topography on u/v-grid. As number of topography grid
	2307	!-- points on uv-grid is different than s-grid, different number of
	2308	!-- surface elements would be required. In order to avoid this,
	2309	!-- treat edges (u(k,j,i+1)) simply by a gradient approach, i.e. these
	2310	!-- points are not masked within diffusion_u. Tests had shown that the
	2311	!-- effect on the flow is negligible.
	2312	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2313	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2314	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 8 )
[2232]	2315	ELSE
[4346]	2316	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 8 )
[2232]	2317	ENDIF
[1]	2318
[2232]	2319	ENDDO
	2320	!
	2321	!-- Special flag to control vertical diffusion at model top - former
	2322	!-- nzt_diff
[4346]	2323	wall_flags_total_0(:,j,i) = IBSET( wall_flags_total_0(:,j,i), 9 )
[2232]	2324	IF ( use_top_fluxes ) &
[4346]	2325	wall_flags_total_0(nzt+1,j,i) = IBCLR( wall_flags_total_0(nzt+1,j,i), 9 )
[1]	2326
[2696]	2327
[2232]	2328	DO k = nzb+1, nzt
	2329	!
	2330	!-- Special flag on u grid, former nzb_u_inner + 1, required
	2331	!-- for disturb_field and initialization. Do not disturb directly at
	2332	!-- topography, as well as initialize u with zero one grid point outside
	2333	!-- of topography.
[4346]	2334	IF ( BTEST( wall_flags_total_0(k-1,j,i), 1 ) .AND. &
	2335	BTEST( wall_flags_total_0(k,j,i), 1 ) .AND. &
	2336	BTEST( wall_flags_total_0(k+1,j,i), 1 ) ) &
	2337	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 20 )
[2232]	2338	!
	2339	!-- Special flag on v grid, former nzb_v_inner + 1, required
	2340	!-- for disturb_field and initialization. Do not disturb directly at
	2341	!-- topography, as well as initialize v with zero one grid point outside
	2342	!-- of topography.
[4346]	2343	IF ( BTEST( wall_flags_total_0(k-1,j,i), 2 ) .AND. &
	2344	BTEST( wall_flags_total_0(k,j,i), 2 ) .AND. &
	2345	BTEST( wall_flags_total_0(k+1,j,i), 2 ) ) &
	2346	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 21 )
[2232]	2347	!
	2348	!-- Special flag on scalar grid, former nzb_s_inner+1. Used for
	2349	!-- lpm_sgs_tke
[4346]	2350	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2351	BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2352	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2353	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 25 )
[2232]	2354	!
	2355	!-- Special flag on scalar grid, nzb_diff_s_outer - 1, required in
	2356	!-- in production_e
	2357	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2358	IF ( BTEST( wall_flags_total_0(k,j,i), 24 ) .AND. &
	2359	BTEST( wall_flags_total_0(k-1,j,i), 24 ) .AND. &
	2360	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2361	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 29 )
[2232]	2362	ELSE
[4346]	2363	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2364	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 29 )
[1]	2365	ENDIF
[2232]	2366	!
	2367	!-- Special flag on scalar grid, nzb_diff_s_outer - 1, required in
	2368	!-- in production_e
	2369	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2370	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2371	BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2372	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2373	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 30 )
[2232]	2374	ELSE
[4346]	2375	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2376	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 30 )
[2232]	2377	ENDIF
	2378	ENDDO
	2379	!
	2380	!-- Flags indicating downward facing walls
[4340]	2381	DO k = nzb+1, nzt+1
[2232]	2382	!
	2383	!-- Scalar grid
[4346]	2384	IF ( BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2385	.NOT. BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2386	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 13 )
[2232]	2387	!
	2388	!-- Downward facing wall on u grid
[4346]	2389	IF ( BTEST( wall_flags_total_0(k-1,j,i), 1 ) .AND. &
	2390	.NOT. BTEST( wall_flags_total_0(k,j,i), 1 ) ) &
	2391	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 15 )
[2232]	2392	!
	2393	!-- Downward facing wall on v grid
[4346]	2394	IF ( BTEST( wall_flags_total_0(k-1,j,i), 2 ) .AND. &
	2395	.NOT. BTEST( wall_flags_total_0(k,j,i), 2 ) ) &
	2396	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 17 )
[2232]	2397	!
	2398	!-- Downward facing wall on w grid
[4346]	2399	IF ( BTEST( wall_flags_total_0(k-1,j,i), 3 ) .AND. &
	2400	.NOT. BTEST( wall_flags_total_0(k,j,i), 3 ) ) &
	2401	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 19 )
[2232]	2402	ENDDO
	2403	!
	2404	!-- Flags indicating upward facing walls
	2405	DO k = nzb, nzt
	2406	!
	2407	!-- Upward facing wall on scalar grid
[4346]	2408	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2409	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2410	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 12 )
[2232]	2411	!
	2412	!-- Upward facing wall on u grid
[4346]	2413	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 1 ) .AND. &
	2414	BTEST( wall_flags_total_0(k+1,j,i), 1 ) ) &
	2415	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 14 )
[1]	2416
[2696]	2417	!
[2232]	2418	!-- Upward facing wall on v grid
[4346]	2419	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 2 ) .AND. &
	2420	BTEST( wall_flags_total_0(k+1,j,i), 2 ) ) &
	2421	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 16 )
[2696]	2422
[2232]	2423	!
	2424	!-- Upward facing wall on w grid
[4346]	2425	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 3 ) .AND. &
	2426	BTEST( wall_flags_total_0(k+1,j,i), 3 ) ) &
	2427	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 18 )
[2232]	2428	!
	2429	!-- Special flag on scalar grid, former nzb_s_inner
[4346]	2430	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .OR. &
	2431	BTEST( wall_flags_total_0(k,j,i), 12 ) .OR. &
	2432	BTEST( wall_flags_total_0(k,j,i), 13 ) ) &
	2433	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 22 )
[2232]	2434	!
	2435	!-- Special flag on scalar grid, nzb_diff_s_inner - 1, required for
	2436	!-- flow_statistics
	2437	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4346]	2438	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2439	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
	2440	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 23 )
[2232]	2441	ELSE
[4346]	2442	IF ( BTEST( wall_flags_total_0(k,j,i), 22 ) ) &
	2443	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 23 )
[1]	2444	ENDIF
[2696]	2445
[1]	2446
[2232]	2447	ENDDO
[4346]	2448	wall_flags_total_0(nzt+1,j,i) = IBSET( wall_flags_total_0(nzt+1,j,i), 22 )
	2449	wall_flags_total_0(nzt+1,j,i) = IBSET( wall_flags_total_0(nzt+1,j,i), 23 )
[4109]	2450	!
	2451	!-- Set flags indicating that topography is close by in horizontal
	2452	!-- direction, i.e. flags that infold the topography. These will be used
	2453	!-- to set advection flags for passive scalars, where due to large
	2454	!-- gradients near buildings stationary numerical oscillations can produce
	2455	!-- unrealistically high concentrations. This is only necessary if
	2456	!-- WS-scheme is applied for scalar advection. Note, these flags will be
	2457	!-- only used for passive scalars such as chemical species or aerosols.
	2458	IF ( scalar_advec == 'ws-scheme' ) THEN
	2459	DO k = nzb, nzt
[4346]	2460	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. ( &
	2461	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-1), 0 ) ) .OR.&
	2462	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-2), 0 ) ) .OR.&
	2463	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-3), 0 ) ) .OR.&
	2464	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+1), 0 ) ) .OR.&
	2465	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+2), 0 ) ) .OR.&
	2466	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+3), 0 ) ) .OR.&
	2467	ANY( .NOT. BTEST( wall_flags_total_0(k,j-1,i-3:i+3), 0 ) ) .OR.&
	2468	ANY( .NOT. BTEST( wall_flags_total_0(k,j-2,i-3:i+3), 0 ) ) .OR.&
	2469	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3,i-3:i+3), 0 ) ) .OR.&
	2470	ANY( .NOT. BTEST( wall_flags_total_0(k,j+1,i-3:i+3), 0 ) ) .OR.&
	2471	ANY( .NOT. BTEST( wall_flags_total_0(k,j+2,i-3:i+3), 0 ) ) .OR.&
	2472	ANY( .NOT. BTEST( wall_flags_total_0(k,j+3,i-3:i+3), 0 ) ) &
	2473	) ) &
	2474	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 31 )
[4109]	2475
	2476	ENDDO
	2477	ENDIF
[2232]	2478	ENDDO
	2479	ENDDO
	2480	!
[2696]	2481	!-- Finally, set identification flags indicating natural terrain or buildings.
[4189]	2482	!-- Natural terrain grid points. Information on the type of the surface is
	2483	!-- stored in bit 1 of 3D Integer array topo. However, this bit is only set
	2484	!-- when topography is read from file. In order to run the land-surface model
	2485	!-- also without topography information, set bit 1 explicitely in this case.
[4294]	2486	!--
	2487	!-- Natural terrain grid points
	2488	!-- If no topography is initialized, the land-surface is at k = nzb.
	2489	IF ( TRIM( topography ) /= 'read_from_file' ) THEN
[4329]	2490	wall_flags_static_0(nzb,:,:) = IBSET( wall_flags_static_0(nzb,:,:), 5 )
[4294]	2491	ELSE
	2492	DO i = nxl, nxr
	2493	DO j = nys, nyn
	2494	DO k = nzb, nzt+1
[4189]	2495	!
[4294]	2496	!-- Natural terrain grid point
	2497	IF ( BTEST( topo(k,j,i), 1 ) ) &
[4329]	2498	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 5 )
[2696]	2499	ENDDO
	2500	ENDDO
[4294]	2501	ENDDO
[2696]	2502	ENDIF
	2503	!
	2504	!-- Building grid points.
[4294]	2505	DO i = nxl, nxr
	2506	DO j = nys, nyn
	2507	DO k = nzb, nzt+1
	2508	IF ( BTEST( topo(k,j,i), 2 ) ) &
[4329]	2509	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 6 )
[2696]	2510	ENDDO
	2511	ENDDO
[4294]	2512	ENDDO
[2696]	2513	!
[4314]	2514	!-- Set flag 4, indicating new topography grid points due to filtering.
	2515	DO i = nxl, nxr
	2516	DO j = nys, nyn
	2517	DO k = nzb, nzt+1
	2518	IF ( BTEST( topo(k,j,i), 4 ) ) &
[4329]	2519	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 4 )
[4314]	2520	ENDDO
	2521	ENDDO
	2522	ENDDO
[4346]	2523
	2524	CALL exchange_horiz_int( wall_flags_static_0, nys, nyn, nxl, nxr, nzt, nbgp )
	2525
	2526	DO i = nxl, nxr
	2527	DO j = nys, nyn
	2528	DO k = nzb, nzt+1
	2529	wall_flags_total_0(k,j,i) = IOR( wall_flags_total_0(k,j,i), wall_flags_static_0(k,j,i) )
	2530	ENDDO
	2531	ENDDO
	2532	ENDDO
[4314]	2533	!
[2232]	2534	!-- Exchange ghost points for wall flags
[4346]	2535	CALL exchange_horiz_int( wall_flags_total_0, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2536	!
	2537	!-- Set boundary conditions also for flags. Can be interpreted as Neumann
	2538	!-- boundary conditions for topography.
	2539	IF ( .NOT. bc_ns_cyc ) THEN
[2696]	2540	IF ( nys == 0 ) THEN
	2541	DO i = 1, nbgp
[4346]	2542	wall_flags_total_0(:,nys-i,:) = wall_flags_total_0(:,nys,:)
[2696]	2543	ENDDO
	2544	ENDIF
	2545	IF ( nyn == ny ) THEN
	2546	DO i = 1, nbgp
[4346]	2547	wall_flags_total_0(:,nyn+i,:) = wall_flags_total_0(:,nyn,:)
[2696]	2548	ENDDO
	2549	ENDIF
[2232]	2550	ENDIF
	2551	IF ( .NOT. bc_lr_cyc ) THEN
[2696]	2552	IF ( nxl == 0 ) THEN
	2553	DO i = 1, nbgp
[4346]	2554	wall_flags_total_0(:,:,nxl-i) = wall_flags_total_0(:,:,nxl)
[2696]	2555	ENDDO
[2232]	2556	ENDIF
[2696]	2557	IF ( nxr == nx ) THEN
	2558	DO i = 1, nbgp
[4346]	2559	wall_flags_total_0(:,:,nxr+i) = wall_flags_total_0(:,:,nxr)
[2232]	2560	ENDDO
[2696]	2561	ENDIF
[2232]	2562	ENDIF
[4168]	2563	!
	2564	!-- Pre-calculate topography top indices (former get_topography_top_index
	2565	!-- function)
	2566	ALLOCATE( topo_top_ind(nysg:nyng,nxlg:nxrg,0:4) )
	2567	!
	2568	!-- Uppermost topography index on scalar grid
	2569	ibit = 12
	2570	topo_top_ind(:,:,0) = MAXLOC( &
	2571	MERGE( 1, 0, &
[4346]	2572	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2573	), DIM = 1 &
	2574	) - 1
	2575	!
	2576	!-- Uppermost topography index on u grid
	2577	ibit = 14
	2578	topo_top_ind(:,:,1) = MAXLOC( &
	2579	MERGE( 1, 0, &
[4346]	2580	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2581	), DIM = 1 &
	2582	) - 1
	2583	!
	2584	!-- Uppermost topography index on v grid
	2585	ibit = 16
	2586	topo_top_ind(:,:,2) = MAXLOC( &
	2587	MERGE( 1, 0, &
[4346]	2588	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2589	), DIM = 1 &
	2590	) - 1
	2591	!
	2592	!-- Uppermost topography index on w grid
	2593	ibit = 18
	2594	topo_top_ind(:,:,3) = MAXLOC( &
	2595	MERGE( 1, 0, &
[4346]	2596	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2597	), DIM = 1 &
	2598	) - 1
	2599	!
	2600	!-- Uppermost topography index on scalar outer grid
	2601	ibit = 24
	2602	topo_top_ind(:,:,4) = MAXLOC( &
	2603	MERGE( 1, 0, &
[4346]	2604	BTEST( wall_flags_total_0(:,:,:), ibit ) &
[4168]	2605	), DIM = 1 &
[4414]	2606	) - 1
	2607
[2696]	2608	END SUBROUTINE set_topo_flags

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