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init_grid.f90 @ 4878

Last change on this file since 4878 was 4868, checked in by raasch, 4 years ago
Height of level k=0 for the u,v-grid is always set 0.0
Property svn:keywords set to `Id`
File size: 115.8 KB

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[1682]	1	!> @file init_grid.f90
[4648]	2	!--------------------------------------------------------------------------------------------------!
[2696]	3	! This file is part of the PALM model system.
[1036]	4	!
[4648]	5	! PALM is free software: you can redistribute it and/or modify it under the terms of the GNU General
	6	! Public License as published by the Free Software Foundation, either version 3 of the License, or
	7	! (at your option) any later version.
[1036]	8	!
[4648]	9	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the
	10	! implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
	11	! Public License for more details.
[1036]	12	!
[4648]	13	! You should have received a copy of the GNU General Public License along with PALM. If not, see
	14	! <http://www.gnu.org/licenses/>.
[1036]	15	!
[4828]	16	! Copyright 1997-2021 Leibniz Universitaet Hannover
[4648]	17	!--------------------------------------------------------------------------------------------------!
[1036]	18	!
[254]	19	! Current revisions:
[1]	20	! -----------------
[4601]	21	!
	22	!
[2233]	23	! Former revisions:
	24	! -----------------
	25	! $Id: init_grid.f90 4868 2021-02-08 10:07:43Z suehring $
[4868]	26	! Height of level k=0 for the u,v-grid is always set 0.0,
	27	! small changes to follow coding standard
	28	!
	29	! 4828 2021-01-05 11:21:41Z Giersch
[4722]	30	! Bugfix in building mapping when static driver is available but no actual building is present
	31	! within the model domain
	32	!
	33	! 4691 2020-09-22 14:38:38Z suehring
[4691]	34	! Reference model topography to the lowest grid point also in ASCII input case
	35	!
	36	! 4653 2020-08-27 08:54:43Z pavelkrc
[4648]	37	! file re-formatted to follow the PALM coding standard
	38	!
	39	! 4630 2020-07-30 14:54:34Z suehring
[4630]	40	! In case of ASCII topography input flag grid points as terrain and building.
	41	!
	42	! 4601 2020-07-14 12:06:09Z suehring
[4601]	43	! Minor formatting adjustments
[4648]	44	!
[4601]	45	! 4564 2020-06-12 14:03:36Z raasch
[4564]	46	! Vertical nesting method of Huq et al. (2019) removed
[4648]	47	!
[4564]	48	! 4543 2020-05-20 14:12:22Z gronemeier
[4543]	49	! Remove non-required check for canyon height
[4648]	50	!
[4543]	51	! 4507 2020-04-22 18:21:45Z gronemeier
[4507]	52	! update origin_z with shifting height of orography (oro_min)
[4648]	53	!
[4507]	54	! 4457 2020-03-11 14:20:43Z raasch
[4457]	55	! use statement for exchange horiz added,
	56	! bugfix for call of exchange horiz 2d
[4648]	57	!
[4457]	58	! 4444 2020-03-05 15:59:50Z raasch
[4444]	59	! bugfix: cpp-directives for serial mode added
[4648]	60	!
[4444]	61	! 4414 2020-02-19 20:16:04Z suehring
[4414]	62	! - Remove deprecated topography arrays nzb_s_inner, nzb_u_inner, etc.
[4648]	63	! - Move initialization of boundary conditions and multigrid into an extra module interface.
	64	!
[4414]	65	! 4386 2020-01-27 15:07:30Z Giersch
[4648]	66	! Allocation statements, comments, naming of variables revised and _wp added to real type values
	67	!
[4386]	68	! 4360 2020-01-07 11:25:50Z suehring
[4356]	69	! Revise error messages for generic tunnel setup.
[4648]	70	!
[4356]	71	! 4346 2019-12-18 11:55:56Z motisi
[4648]	72	! Introduction of wall_flags_total_0, which currently sets bits based on static topography
	73	! information used in wall_flags_static_0
	74	!
[4346]	75	! 4340 2019-12-16 08:17:03Z Giersch
[4340]	76	! Topography closed channel flow with symmetric boundaries implemented
[4648]	77	!
[4340]	78	! 4329 2019-12-10 15:46:36Z motisi
[4329]	79	! Renamed wall_flags_0 to wall_flags_static_0
[4648]	80	!
[4329]	81	! 4328 2019-12-09 18:53:04Z suehring
[4328]	82	! Minor change in nzb_max computation. Commentation added.
[4648]	83	!
[4328]	84	! 4314 2019-11-29 10:29:20Z suehring
[4648]	85	! Set additional topography flag 4 to mark topography grid points emerged from the filtering process.
	86	!
[4314]	87	! 4294 2019-11-13 18:34:16Z suehring
[4648]	88	! Bugfix, always set bit 5 and 6 of wall_flags, indicating terrain- and building surfaces in all
	89	! cases, in order to enable terrain-following output also when no land- or urban-surface model is
	90	! applied.
	91	!
[4294]	92	! 4265 2019-10-15 16:16:24Z suehring
[4648]	93	! Bugfix for last commit, exchange oro_max variable only when it is allocated (not necessarily the
	94	! case when topography is input from ASCII file).
	95	!
[4265]	96	! 4245 2019-09-30 08:40:37Z pavelkrc
[4245]	97	! Store oro_max (building z-offset) in 2D for building surfaces
[4648]	98	!
[4245]	99	! 4189 2019-08-26 16:19:38Z suehring
[4189]	100	! - Add check for proper setting of namelist parameter topography
	101	! - Set flag to indicate land surfaces in case no topography is provided
[4648]	102	!
[4189]	103	! 4182 2019-08-22 15:20:23Z scharf
[4182]	104	! Corrected "Former revisions" section
[4648]	105	!
[4182]	106	! 4168 2019-08-16 13:50:17Z suehring
[4648]	107	! Pre-calculate topography top index and store it on an array (replaces former functions
	108	! get_topography_top_index)
	109	!
[4168]	110	! 4159 2019-08-15 13:31:35Z suehring
[4648]	111	! Revision of topography processing. This was not consistent between 2D and 3D buildings.
	112	!
[4159]	113	! 4144 2019-08-06 09:11:47Z raasch
[4144]	114	! relational operators .EQ., .NE., etc. replaced by ==, /=, etc.
[4648]	115	!
[4144]	116	! 4115 2019-07-24 12:50:49Z suehring
[4648]	117	! Bugfix in setting near-surface flag 24, inidicating wall-bounded grid points
	118	!
[4115]	119	! 4110 2019-07-22 17:05:21Z suehring
[4110]	120	! - Separate initialization of advection flags for momentum and scalars.
	121	! - Change subroutine interface for ws_init_flags_scalar to pass boundary flags
[4648]	122	!
[4110]	123	! 4109 2019-07-22 17:00:34Z suehring
[3927]	124	! Fix bad commit
[4648]	125	!
[3927]	126	! 3926 2019-04-23 12:56:42Z suehring
[4648]	127	! Minor bugfix in building mapping when all building IDs in the model domain are missing
	128	!
[3925]	129	! 3857 2019-04-03 13:00:16Z knoop
[4648]	130	! In projection of non-building 3D objects onto numerical grid remove dependency on building_type
	131	!
[3855]	132	! 3763 2019-02-25 17:33:49Z suehring
[4648]	133	! Replace work-around for ghost point exchange of 1-byte arrays with specific routine as already
	134	! done in other routines
	135	!
[3763]	136	! 3761 2019-02-25 15:31:42Z raasch
[3761]	137	! unused variables removed
[4648]	138	!
[3761]	139	! 3661 2019-01-08 18:22:50Z suehring
[4648]	140	! Remove setting of nzb_max to nzt at non-cyclic boundary PEs, instead, order degradation of
	141	! advection scheme is handeled directly in advec_ws
	142	!
[3661]	143	! 3655 2019-01-07 16:51:22Z knoop
[3538]	144	! Comment added
[2716]	145	!
[4182]	146	! Revision 1.1 1997/08/11 06:17:45 raasch
	147	! Initial revision (Testversion)
	148	!
	149	!
[1]	150	! Description:
[4648]	151	! -------------------------------------------------------------------------------------------------!
[1682]	152	!> Creating grid depending constants
[2696]	153	!> @todo: Rearrange topo flag list
[4648]	154	!> @todo: reference 3D buildings on top of orography is not tested and may need further improvement
	155	!> for steep slopes
	156	!> @todo: Use more advanced setting of building type at filled holes
	157	!--------------------------------------------------------------------------------------------------!
[1682]	158	SUBROUTINE init_grid
[1]	159
[4648]	160	USE arrays_3d, &
[3857]	161	ONLY: dd2zu, ddzu, ddzu_pres, ddzw, dzu, dzw, x, xu, y, yv, zu, zw
[4414]	162
[4648]	163	USE control_parameters, &
	164	ONLY: constant_flux_layer, dz, dz_max, dz_stretch_factor, &
	165	dz_stretch_factor_array, dz_stretch_level, dz_stretch_level_end, &
	166	dz_stretch_level_end_index, dz_stretch_level_start_index, &
[4868]	167	dz_stretch_level_start, message_string, &
[4648]	168	number_stretch_level_end, &
	169	number_stretch_level_start, &
	170	ocean_mode, &
	171	psolver, &
	172	symmetry_flag, &
	173	topography, &
[4414]	174	use_surface_fluxes
	175
[4648]	176	USE grid_variables, &
[2232]	177	ONLY: ddx, ddx2, ddy, ddy2, dx, dx2, dy, dy2, zu_s_inner, zw_w_inner
[4414]	178
[4648]	179	USE indices, &
	180	ONLY: nbgp, &
	181	nx, &
	182	nxl, &
	183	nxlg, &
	184	nxr, &
	185	nxrg, &
	186	ny, &
	187	nyn, &
	188	nyng, &
	189	nys, &
	190	nysg, &
	191	nz, &
	192	nzb, &
	193	nzb_diff, &
	194	nzb_max, &
	195	nzt, &
	196	topo_top_ind, &
[4414]	197	topo_min_level
	198
[1320]	199	USE kinds
[2696]	200
[1]	201	USE pegrid
	202
	203	IMPLICIT NONE
	204
[4648]	205	INTEGER(iwp) :: i !< index variable along x
[3182]	206	INTEGER(iwp) :: j !< index variable along y
	207	INTEGER(iwp) :: k !< index variable along z
	208	INTEGER(iwp) :: k_top !< topography top index on local PE
	209	INTEGER(iwp) :: n !< loop variable for stretching
[4648]	210	INTEGER(iwp) :: number_dz !< number of user-specified dz values
[3182]	211	INTEGER(iwp) :: nzb_local_max !< vertical grid index of maximum topography height
	212	INTEGER(iwp) :: nzb_local_min !< vertical grid index of minimum topography height
[1]	213
[2696]	214	INTEGER(iwp), DIMENSION(:,:,:), ALLOCATABLE :: topo !< input array for 3D topography and dummy array for setting "outer"-flags
[2232]	215
[3065]	216	REAL(wp) :: dz_level_end !< distance between calculated height level for u/v-grid and user-specified end level for stretching
[1886]	217	REAL(wp) :: dz_stretched !< stretched vertical grid spacing
[861]	218
[4648]	219	REAL(wp), DIMENSION(:), ALLOCATABLE :: min_dz_stretch_level_end !< Array that contains all minimum heights where the stretching
	220	!< can end
[1]	221
[4648]	222
[1]	223	!
[709]	224	!-- Calculation of horizontal array bounds including ghost layers
[667]	225	nxlg = nxl - nbgp
	226	nxrg = nxr + nbgp
	227	nysg = nys - nbgp
	228	nyng = nyn + nbgp
[709]	229
[667]	230	!
[1]	231	!-- Allocate grid arrays
[4386]	232	ALLOCATE( x(0:nx) )
	233	ALLOCATE( xu(0:nx) )
[4648]	234
[3857]	235	DO i = 0, nx
	236	xu(i) = i * dx
	237	x(i) = i * dx + 0.5_wp * dx
	238	ENDDO
	239
[4386]	240	ALLOCATE( y(0:ny) )
	241	ALLOCATE( yv(0:ny) )
[4648]	242
[3857]	243	DO j = 0, ny
	244	yv(j) = j * dy
	245	y(j) = j * dy + 0.5_wp * dy
	246	ENDDO
	247
[4386]	248	ALLOCATE( ddzu(1:nzt+1) )
	249	ALLOCATE( ddzw(1:nzt+1) )
	250	ALLOCATE( dd2zu(1:nzt) )
	251	ALLOCATE( dzu(1:nzt+1) )
	252	ALLOCATE( dzw(1:nzt+1) )
	253	ALLOCATE( zu(nzb:nzt+1) )
	254	ALLOCATE( zw(nzb:nzt+1) )
[1]	255
	256	!
[4648]	257	!-- For constructing an appropriate grid, the vertical grid spacing dz has to be specified with a
	258	!-- non-negative value in the parameter file.
[3065]	259	IF ( dz(1) == -1.0_wp ) THEN
[254]	260	message_string = 'missing dz'
[4648]	261	CALL message( 'init_grid', 'PA0200', 1, 2, 0, 6, 0 )
[3065]	262	ELSEIF ( dz(1) <= 0.0_wp ) THEN
	263	WRITE( message_string, * ) 'dz=',dz(1),' <= 0.0'
[254]	264	CALL message( 'init_grid', 'PA0201', 1, 2, 0, 6, 0 )
[1]	265	ENDIF
[94]	266
[1]	267	!
[4648]	268	!-- Initialize dz_stretch_level_start with the value of dz_stretch_level if it was set by the user.
[3065]	269	IF ( dz_stretch_level /= -9999999.9_wp ) THEN
	270	dz_stretch_level_start(1) = dz_stretch_level
	271	ENDIF
[4648]	272
[3065]	273	!
[4648]	274	!-- Determine number of dz values and stretching levels specified by the user to allow right
	275	!-- controlling of the stretching mechanism and to perform error checks. The additional requirement
	276	!-- that dz /= dz_max for counting number of user-specified dz values is necessary. Otherwise
	277	!-- restarts would abort if the old stretching mechanism with dz_stretch_level is used (Attention:
	278	!-- The user is not allowed to specify a dz value equal to the default of dz_max = 999.0).
	279	number_dz = COUNT( dz /= -1.0_wp .AND. dz /= dz_max)
	280	number_stretch_level_start = COUNT( dz_stretch_level_start /= -9999999.9_wp )
	281	number_stretch_level_end = COUNT( dz_stretch_level_end /= 9999999.9_wp )
[3065]	282
	283	!
[4648]	284	!-- The number of specified end levels +1 has to be the same as the number
[3065]	285	!-- of specified dz values
	286	IF ( number_dz /= number_stretch_level_end + 1 ) THEN
[4648]	287	WRITE( message_string, * ) 'The number of values for dz = ', number_dz, &
	288	'has to be the same as& ', 'the number of values for ', &
	289	'dz_stretch_level_end + 1 = ', number_stretch_level_end+1
[4601]	290	CALL message( 'init_grid', 'PA0156', 1, 2, 0, 6, 0 )
[3065]	291	ENDIF
[4648]	292
[3065]	293	!
[4648]	294	!-- The number of specified start levels has to be the same or one less than the number of specified
	295	!-- dz values
	296	IF ( number_dz /= number_stretch_level_start + 1 .AND. &
	297	number_dz /= number_stretch_level_start ) THEN
	298	WRITE( message_string, * ) 'The number of values for dz = ', number_dz, &
	299	'has to be the same as or one ', &
	300	'more than& the number of values for ', &
	301	'dz_stretch_level_start = ', number_stretch_level_start
[4601]	302	CALL message( 'init_grid', 'PA0211', 1, 2, 0, 6, 0 )
[3065]	303	ENDIF
[4648]	304
	305	!-- The number of specified start levels has to be the same or one more than the number of specified
	306	!-- 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
[4648]	309	WRITE( message_string, * ) 'The number of values for ', &
	310	'dz_stretch_level_start = ', dz_stretch_level_start, &
	311	'has to be the ', 'same or one more than& the number of ', &
	312	'values for dz_stretch_level_end = ', number_stretch_level_end
[4601]	313	CALL message( 'init_grid', 'PA0216', 1, 2, 0, 6, 0 )
[3065]	314	ENDIF
	315
	316	!
	317	!-- Initialize dz for the free atmosphere with the value of dz_max
[4648]	318	IF ( dz(number_stretch_level_start+1) == -1.0_wp .AND. number_stretch_level_start /= 0 ) THEN
[3065]	319	dz(number_stretch_level_start+1) = dz_max
	320	ENDIF
[4648]	321
[3065]	322	!
[4648]	323	!-- Initialize the stretching factor if (infinitely) stretching in the free atmosphere is desired
	324	!-- (dz_stretch_level_end was not specified for the free atmosphere)
	325	IF ( number_stretch_level_start == number_stretch_level_end + 1 ) THEN
	326	dz_stretch_factor_array(number_stretch_level_start) = dz_stretch_factor
[3065]	327	ENDIF
[4648]	328
[3065]	329	!
	330	!-- Allocation of arrays for stretching
	331	ALLOCATE( min_dz_stretch_level_end(number_stretch_level_start) )
[3066]	332
[3065]	333	!
[4386]	334	!-- Define the vertical grid levels. Start with atmosphere branch
[3294]	335	IF ( .NOT. ocean_mode ) THEN
[4648]	336
[94]	337	!
[4648]	338	!-- The stretching region has to be large enough to allow for a smooth transition between two
	339	!-- different grid spacings. The number 4 is an empirical value.
[3065]	340	DO n = 1, number_stretch_level_start
[4648]	341	min_dz_stretch_level_end(n) = dz_stretch_level_start(n) + 4 * MAX( dz(n),dz(n+1) )
[3065]	342	ENDDO
	343
[4648]	344	IF ( ANY( min_dz_stretch_level_end(1:number_stretch_level_start) > &
	345	dz_stretch_level_end(1:number_stretch_level_start) ) ) THEN
	346	message_string= 'Each dz_stretch_level_end has to be larger ' // &
	347	'than its corresponding value for &' // &
	348	'dz_stretch_level_start + 4*MAX(dz(n),dz(n+1)) '// &
[4601]	349	'to allow for smooth grid stretching'
	350	CALL message( 'init_grid', 'PA0224', 1, 2, 0, 6, 0 )
[3065]	351	ENDIF
[4648]	352
[3065]	353	!
[4648]	354	!-- Stretching must not be applied within the surface layer (first two grid points). For the
	355	!-- default case dz_stretch_level_start is negative. Therefore the absolut value is checked here.
[4386]	356	IF ( ANY( ABS( dz_stretch_level_start ) <= dz(1) * 1.5_wp ) ) THEN
[4648]	357	WRITE( message_string, * ) 'Each dz_stretch_level_start has to be ', &
	358	'larger than ', dz(1) * 1.5
[4601]	359	CALL message( 'init_grid', 'PA0226', 1, 2, 0, 6, 0 )
[3065]	360	ENDIF
	361
	362	!
[4648]	363	!-- The stretching has to start and end on a grid level. Therefore user-specified values are
	364	!-- mapped to the next lowest level. The calculation of the first level is realized differently
	365	!-- just because of historical reasons (the advanced/new stretching mechanism was realized in a
	366	!-- way that results don't change if the old parameters dz_stretch_level, dz_stretch_factor and
	367	!-- dz_max are used).
	368	IF ( number_stretch_level_start /= 0 ) THEN
	369	dz_stretch_level_start(1) = INT( (dz_stretch_level_start(1) - dz(1)/2.0) / dz(1) ) &
[3065]	370	* dz(1) + dz(1)/2.0
	371	ENDIF
[4648]	372
[3065]	373	IF ( number_stretch_level_start > 1 ) THEN
	374	DO n = 2, number_stretch_level_start
[4648]	375	dz_stretch_level_start(n) = INT( dz_stretch_level_start(n) / dz(n) ) * dz(n)
[3065]	376	ENDDO
	377	ENDIF
[4648]	378
[3065]	379	IF ( number_stretch_level_end /= 0 ) THEN
	380	DO n = 1, number_stretch_level_end
[4648]	381	dz_stretch_level_end(n) = INT( dz_stretch_level_end(n) / dz(n+1) ) * dz(n+1)
[3065]	382	ENDDO
	383	ENDIF
[4386]	384
[3065]	385	!
	386	!-- Determine stretching factor if necessary
[4648]	387	IF ( number_stretch_level_end >= 1 ) THEN
[3065]	388	CALL calculate_stretching_factor( number_stretch_level_end )
	389	ENDIF
	390
	391	!
[4868]	392	!-- Grid for atmosphere with surface at z=0. This corresponds to k=0 on the w-grid AND
	393	!-- the u-grid.
	394	!-- First compute the u- and v-levels.
	395	!-- The second u-level (k=1) corresponds to the top of the surface layer.
	396	zu(0) = 0.0_wp
	397	zu(1) = dz(1) * 0.5_wp
[4648]	398
[3065]	399	!
[4648]	400	!-- Determine u and v height levels considering the possibility of grid stretching in several
	401	!-- heights.
[3065]	402	n = 1
	403	dz_stretch_level_start_index = nzt+1
	404	dz_stretch_level_end_index = nzt+1
	405	dz_stretched = dz(1)
[1]	406
[4648]	407	!-- The default value of dz_stretch_level_start is negative, thus the first condition is true
	408	!-- even if no stretching shall be applied. Hence, the second condition is also necessary.
[4340]	409	DO k = 2, nzt+1-symmetry_flag
[4648]	410	IF ( dz_stretch_level_start(n) <= zu(k-1) .AND. &
	411	dz_stretch_level_start(n) /= -9999999.9_wp ) THEN
[3065]	412	dz_stretched = dz_stretched * dz_stretch_factor_array(n)
[4648]	413
	414	IF ( dz(n) > dz(n+1) ) THEN
[3065]	415	dz_stretched = MAX( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (higher) dz
	416	ELSE
	417	dz_stretched = MIN( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (lower) dz
	418	ENDIF
[4648]	419
	420	IF ( dz_stretch_level_start_index(n) == nzt+1 ) dz_stretch_level_start_index(n) = k-1
	421
[94]	422	ENDIF
[4648]	423
[94]	424	zu(k) = zu(k-1) + dz_stretched
[4648]	425
[3065]	426	!
[4648]	427	!-- Make sure that the stretching ends exactly at dz_stretch_level_end
	428	dz_level_end = ABS( zu(k) - dz_stretch_level_end(n) )
	429
[4868]	430	IF ( dz_level_end < dz(n+1) / 3.0 ) THEN
[3065]	431	zu(k) = dz_stretch_level_end(n)
	432	dz_stretched = dz(n+1)
	433	dz_stretch_level_end_index(n) = k
[4648]	434	n = n + 1
[3065]	435	ENDIF
[94]	436	ENDDO
[4648]	437
[4340]	438	!
[4648]	439	!-- If a closed channel flow is simulated, make sure that grid structure is the same for both
	440	!-- bottom and top boundary. (Hint: Using a different dz at the bottom and at the top makes no
	441	!-- sense due to symmetric boundaries where dz should be equal. Therefore, different dz at the
	442	!-- bottom and top causes an abort (see check_parameters).)
	443	IF ( topography == 'closed_channel' ) THEN
[4340]	444	zu(nzt+1) = zu(nzt) + dz(1) * 0.5_wp
	445	ENDIF
[1]	446
	447	!
[4648]	448	!-- Compute the w-levels. They are always staggered half-way between the corresponding u-levels.
	449	!-- In case of dirichlet bc for u and v at the ground the first u- and w-level (k=0) are defined
	450	!-- at same height (z=0).
	451	!-- Per default, the top w-level is extrapolated linearly. In case of a closed channel flow,
	452	!-- zu(nzt+1) and zw(nzt) must be set explicitely.
	453	!-- (Hint: Using a different dz at the bottom and at the top makes no sense due to symmetric
	454	!-- boundaries where dz should be equal. Therefore, different dz at the bottom and top causes an
	455	!-- abort (see check_parameters).)
[1353]	456	zw(0) = 0.0_wp
[4340]	457	DO k = 1, nzt-symmetry_flag
[1353]	458	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	459	ENDDO
[4648]	460	IF ( topography == 'closed_channel' ) THEN
[4340]	461	zw(nzt) = zw(nzt-1) + dz(1)
	462	zw(nzt+1) = zw(nzt) + dz(1)
	463	ELSE
	464	zw(nzt+1) = zw(nzt) + 2.0_wp * ( zu(nzt+1) - zw(nzt) )
	465	ENDIF
[1]	466
[4386]	467	ELSE !ocean branch
[3065]	468
[1]	469	!
[4648]	470	!-- The stretching region has to be large enough to allow for a smooth transition between two
	471	!-- different grid spacings. The number 4 is an empirical value
[3065]	472	DO n = 1, number_stretch_level_start
[4648]	473	min_dz_stretch_level_end(n) = dz_stretch_level_start(n) - 4 * MAX( dz(n),dz(n+1) )
[3065]	474	ENDDO
[4648]	475
	476	IF ( ANY( min_dz_stretch_level_end (1:number_stretch_level_start) < &
	477	dz_stretch_level_end(1:number_stretch_level_start) ) ) THEN
	478	message_string= 'Each dz_stretch_level_end has to be less ' // &
	479	'than its corresponding value for &' // &
	480	'dz_stretch_level_start - 4*MAX(dz(n),dz(n+1)) '// &
[3065]	481	'to allow for smooth grid stretching'
	482	CALL message( 'init_grid', 'PA0224', 1, 2, 0, 6, 0 )
	483	ENDIF
[4648]	484
[3065]	485	!
[4648]	486	!-- Stretching must not be applied close to the surface (last two grid points). For the default
	487	!-- case dz_stretch_level_start is negative.
	488	IF ( ANY( dz_stretch_level_start >= - dz(1) * 1.5_wp ) ) THEN
	489	WRITE( message_string, * ) 'Each dz_stretch_level_start has to be ', &
	490	'less than ', -dz(1) * 1.5
[3065]	491	CALL message( 'init_grid', 'PA0226', 1, 2, 0, 6, 0 )
	492	ENDIF
	493
	494	!
[4648]	495	!-- The stretching has to start and end on a grid level. Therefore user-specified values are
	496	!-- mapped to the next highest level. The calculation of the first level is realized differently
	497	!-- just because of historical reasons (the advanced/new stretching mechanism was realized in a
	498	!-- way that results don't change if the old parameters dz_stretch_level, dz_stretch_factor and
	499	!-- dz_max are used)
	500	IF ( number_stretch_level_start /= 0 ) THEN
	501	dz_stretch_level_start(1) = INT( (dz_stretch_level_start(1) + dz(1)/2.0) / dz(1) ) &
[3065]	502	* dz(1) - dz(1)/2.0
	503	ENDIF
[4648]	504
	505	IF ( number_stretch_level_start > 1 ) THEN
[3065]	506	DO n = 2, number_stretch_level_start
[4648]	507	dz_stretch_level_start(n) = INT( dz_stretch_level_start(n) / dz(n) ) * dz(n)
[3065]	508	ENDDO
	509	ENDIF
[4648]	510
	511	IF ( number_stretch_level_end /= 0 ) THEN
[3065]	512	DO n = 1, number_stretch_level_end
[4648]	513	dz_stretch_level_end(n) = INT( dz_stretch_level_end(n) / dz(n+1) ) * dz(n+1)
[3065]	514	ENDDO
	515	ENDIF
[4648]	516
[3065]	517	!
	518	!-- Determine stretching factor if necessary
[4648]	519	IF ( number_stretch_level_end >= 1 ) THEN
[3065]	520	CALL calculate_stretching_factor( number_stretch_level_end )
	521	ENDIF
	522
	523	!
[843]	524	!-- Grid for ocean with free water surface is at k=nzt (w-grid).
[4648]	525	!-- In case of neumann bc at the ground the first first u-level (k=0) lies below the first
	526	!-- w-level (k=0). In case of dirichlet bc the first u- and w-level are defined at same height,
	527	!-- but staggered from the second level.
[4386]	528	!-- The second u-level (k=1) corresponds to the top of the surface layer.
[3065]	529	!-- z values are negative starting from z=0 (surface)
	530	zu(nzt+1) = dz(1) * 0.5_wp
	531	zu(nzt) = - dz(1) * 0.5_wp
[94]	532
[3065]	533	!
[4648]	534	!-- Determine u and v height levels considering the possibility of grid stretching in several
	535	!-- heights.
[3065]	536	n = 1
	537	dz_stretch_level_start_index = 0
	538	dz_stretch_level_end_index = 0
	539	dz_stretched = dz(1)
	540
[94]	541	DO k = nzt-1, 0, -1
[4648]	542
	543	IF ( dz_stretch_level_start(n) >= zu(k+1) ) THEN
[3065]	544	dz_stretched = dz_stretched * dz_stretch_factor_array(n)
	545
[4648]	546	IF ( dz(n) > dz(n+1) ) THEN
[3065]	547	dz_stretched = MAX( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (higher) dz
	548	ELSE
	549	dz_stretched = MIN( dz_stretched, dz(n+1) ) !Restrict dz_stretched to the user-specified (lower) dz
	550	ENDIF
[4648]	551
	552	IF ( dz_stretch_level_start_index(n) == 0 ) dz_stretch_level_start_index(n) = k+1
	553
[3065]	554	ENDIF
[4648]	555
[3065]	556	zu(k) = zu(k+1) - dz_stretched
[4648]	557
[1418]	558	!
[4648]	559	!-- Make sure that the stretching ends exactly at dz_stretch_level_end
	560	dz_level_end = ABS( zu(k) - dz_stretch_level_end(n) )
	561
	562	IF ( dz_level_end < dz(n+1)/3.0 ) THEN
[3065]	563	zu(k) = dz_stretch_level_end(n)
	564	dz_stretched = dz(n+1)
	565	dz_stretch_level_end_index(n) = k
[4648]	566	n = n + 1
[94]	567	ENDIF
	568	ENDDO
[4648]	569
[94]	570	!
[4648]	571	!-- Compute the w-levels. They are always staggered half-way between the corresponding u-levels,
[4868]	572	!-- except for u and v at the ground. In this case the first u- and
[4648]	573	!-- w-level are defined at same height. The top w-level (nzt+1) is not used but set for
[4868]	574	!-- consistency, since w and all scalar variables are defined up to nzt+1.
[3065]	575	zw(nzt+1) = dz(1)
[1353]	576	zw(nzt) = 0.0_wp
[94]	577	DO k = 0, nzt
[1353]	578	zw(k) = ( zu(k) + zu(k+1) ) * 0.5_wp
[94]	579	ENDDO
	580
[843]	581	!
[4868]	582	!-- Like for the atmosphere, the first u-grid and w-grid-level are defined at same height.
	583	zu(0) = zw(0)
[843]	584
[4386]	585	ENDIF !End of defining the vertical grid levels
[94]	586
	587	!
[1]	588	!-- Compute grid lengths.
	589	DO k = 1, nzt+1
	590	dzu(k) = zu(k) - zu(k-1)
[1353]	591	ddzu(k) = 1.0_wp / dzu(k)
[1]	592	dzw(k) = zw(k) - zw(k-1)
[1353]	593	ddzw(k) = 1.0_wp / dzw(k)
[1]	594	ENDDO
	595
	596	DO k = 1, nzt
[1353]	597	dd2zu(k) = 1.0_wp / ( dzu(k) + dzu(k+1) )
[1]	598	ENDDO
[4648]	599
	600	!
	601	!-- The FFT- SOR-pressure solvers assume grid spacings of a staggered grid everywhere. For the
	602	!-- actual grid, the grid spacing at the lowest level is only dz/2, but should be dz. Therefore, an
	603	!-- additional array containing with appropriate grid information is created for these solvers.
[1575]	604	IF ( psolver(1:9) /= 'multigrid' ) THEN
[667]	605	ALLOCATE( ddzu_pres(1:nzt+1) )
	606	ddzu_pres = ddzu
[864]	607	ddzu_pres(1) = ddzu_pres(2) ! change for lowest level
[1]	608	ENDIF
	609
	610	!
	611	!-- Compute the reciprocal values of the horizontal grid lengths.
[1353]	612	ddx = 1.0_wp / dx
	613	ddy = 1.0_wp / dy
[1]	614	dx2 = dx * dx
	615	dy2 = dy * dy
[1353]	616	ddx2 = 1.0_wp / dx2
	617	ddy2 = 1.0_wp / dy2
[1]	618
	619	!
[2696]	620	!-- Allocate 3D array to set topography
	621	ALLOCATE( topo(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	622	topo = 0
	623	!
[4648]	624	!-- Initialize topography by generic topography or read topography from file.
[2696]	625	CALL init_topo( topo )
	626	!
[4648]	627	!-- Set flags to mask topography on the grid.
[4414]	628	CALL set_topo_flags( topo )
[2696]	629
	630	!
[4648]	631	!-- Determine the maximum level of topography. It is used for steering the degradation of order of
	632	!-- the applied advection scheme, as well in the lpm.
[2696]	633	k_top = 0
	634	DO i = nxl, nxr
	635	DO j = nys, nyn
	636	DO k = nzb, nzt + 1
[4109]	637	k_top = MAX( k_top, MERGE( k, 0, .NOT. BTEST( topo(k,j,i), 0 ) ) )
[2696]	638	ENDDO
	639	ENDDO
[1]	640	ENDDO
[2696]	641	#if defined( __parallel )
[4648]	642	CALL MPI_ALLREDUCE( k_top, nzb_max, 1, MPI_INTEGER, MPI_MAX, comm2d, ierr )
[2696]	643	#else
[4328]	644	nzb_max = k_top
[2696]	645	#endif
[1]	646	!
[4328]	647	!-- Increment nzb_max by 1 in order to allow for proper diverengence correction.
	648	!-- Further, in case topography extents up to the model top, limit to nzt.
[4648]	649	nzb_max = MIN( nzb_max+1, nzt )
[4328]	650	!
[4648]	651	!-- Determine minimum index of topography. Usually, this will be nzb. In case there is elevated
	652	!-- topography, however, the lowest topography will be higher.
	653	!-- This index is e.g. used to calculate mean first-grid point atmosphere temperature, surface
	654	!-- pressure and density, etc. .
[2968]	655	topo_min_level = 0
	656	#if defined( __parallel )
[4648]	657	CALL MPI_ALLREDUCE( MINVAL( topo_top_ind(nys:nyn,nxl:nxr,0) ), topo_min_level, 1, MPI_INTEGER, &
	658	MPI_MIN, comm2d, ierr )
[2968]	659	#else
[4168]	660	topo_min_level = MINVAL( topo_top_ind(nys:nyn,nxl:nxr,0) )
[2968]	661	#endif
[3182]	662
[2696]	663	!
[4648]	664	!-- Check topography for consistency with model domain. Therefore, use maximum and minium
	665	!-- topography-top indices. Note, minimum topography top index is already calculated.
[2696]	666	IF ( TRIM( topography ) /= 'flat' ) THEN
	667	#if defined( __parallel )
[4648]	668	CALL MPI_ALLREDUCE( MAXVAL( topo_top_ind(nys:nyn,nxl:nxr,0) ), nzb_local_max, 1, &
	669	MPI_INTEGER, MPI_MAX, comm2d, ierr )
[2696]	670	#else
[4168]	671	nzb_local_max = MAXVAL( topo_top_ind(nys:nyn,nxl:nxr,0) )
[2696]	672	#endif
[2968]	673	nzb_local_min = topo_min_level
[2696]	674	!
	675	!-- Consistency checks
	676	IF ( nzb_local_min < 0 .OR. nzb_local_max > nz + 1 ) THEN
[4648]	677	WRITE( message_string, * ) 'nzb_local values are outside the model domain', &
	678	'&MINVAL( nzb_local ) = ', nzb_local_min, &
	679	'&MAXVAL( nzb_local ) = ', nzb_local_max
[2696]	680	CALL message( 'init_grid', 'PA0210', 1, 2, 0, 6, 0 )
	681	ENDIF
	682	ENDIF
[1]	683	!
[4648]	684	!-- Define vertical gridpoint from (or to) which on the usual finite difference form (which does not
	685	!-- use surface fluxes) is applied.
[1691]	686	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[1]	687	nzb_diff = nzb + 2
	688	ELSE
	689	nzb_diff = nzb + 1
	690	ENDIF
	691
[4414]	692	IF ( TRIM( topography ) /= 'flat' ) THEN
[2696]	693	!
[4648]	694	!-- Allocate and set the arrays containing the topography height (for output reasons only).
[4414]	695	IF ( nxr == nx .AND. nyn /= ny ) THEN
[4648]	696	ALLOCATE( zu_s_inner(nxl:nxr+1,nys:nyn), zw_w_inner(nxl:nxr+1,nys:nyn) )
[4414]	697	ELSEIF ( nxr /= nx .AND. nyn == ny ) THEN
[4648]	698	ALLOCATE( zu_s_inner(nxl:nxr,nys:nyn+1), zw_w_inner(nxl:nxr,nys:nyn+1) )
[4414]	699	ELSEIF ( nxr == nx .AND. nyn == ny ) THEN
[4648]	700	ALLOCATE( zu_s_inner(nxl:nxr+1,nys:nyn+1), zw_w_inner(nxl:nxr+1,nys:nyn+1) )
[4414]	701	ELSE
[4648]	702	ALLOCATE( zu_s_inner(nxl:nxr,nys:nyn), zw_w_inner(nxl:nxr,nys:nyn) )
[2696]	703	ENDIF
[1]	704
[4414]	705	zu_s_inner = 0.0_wp
	706	zw_w_inner = 0.0_wp
[1]	707	!
[4648]	708	!-- Determine local topography height on scalar and w-grid. Note, setting lateral boundary values
	709	!-- is not necessary, realized via wall_flags_static_0 array. Further, please note that loop
	710	!-- bounds are different from nxl to nxr and nys to nyn on south and right model boundary, hence,
[4414]	711	!-- use intrinsic lbound and ubound functions to infer array bounds.
	712	DO i = LBOUND(zu_s_inner, 1), UBOUND(zu_s_inner, 1)
	713	DO j = LBOUND(zu_s_inner, 2), UBOUND(zu_s_inner, 2)
[2696]	714	!
[4648]	715	!-- Topography height on scalar grid. Therefore, determine index of upward-facing surface
	716	!-- element on scalar grid.
[4414]	717	zu_s_inner(i,j) = zu(topo_top_ind(j,i,0))
[2696]	718	!
[4648]	719	!-- Topography height on w grid. Therefore, determine index of upward-facing surface
	720	!-- element on w grid.
[4414]	721	zw_w_inner(i,j) = zw(topo_top_ind(j,i,3))
	722	ENDDO
[2696]	723	ENDDO
	724	ENDIF
[4444]	725
[2696]	726	END SUBROUTINE init_grid
	727
[3065]	728
[2696]	729	! Description:
[4648]	730	! -------------------------------------------------------------------------------------------------!
	731	!> Calculation of the stretching factor through an iterative method. Ideas were taken from the paper
	732	!> "Regional stretched grid generation and its application to the NCAR RegCM (1999)". Normally, no
	733	!> analytic solution exists because the system of equations has two variables (r,l) but four
	734	!> requirements (l=integer, r=[0,88;1,2], Eq(6), Eq(5) starting from index j=1) which results into
	735	!> an overdetermined system.
	736	!--------------------------------------------------------------------------------------------------!
[3065]	737	SUBROUTINE calculate_stretching_factor( number_end )
[4648]	738
	739	USE control_parameters, &
	740	ONLY: dz, dz_stretch_factor_array, dz_stretch_level_end, dz_stretch_level_start, &
	741	message_string
	742
[3065]	743	USE kinds
[4648]	744
[3065]	745	IMPLICIT NONE
[4648]	746
	747	REAL(wp), PARAMETER :: stretch_factor_interval = 1.0E-06_wp !< interval for sampling possible stretching factors
	748	REAL(wp), PARAMETER :: stretch_factor_lower_limit = 0.88_wp !< lowest possible stretching factor
	749	REAL(wp), PARAMETER :: stretch_factor_upper_limit = 1.12_wp !< highest possible stretching factor
	750
	751	INTEGER(iwp) :: iterations !< number of iterations until stretch_factor_lower/upper_limit is reached
	752	INTEGER(iwp) :: l_rounded !< after l_rounded grid levels dz(n) is strechted to dz(n+1) with stretch_factor_2
[3065]	753	INTEGER(iwp) :: n !< loop variable for stretching
[4648]	754
[3065]	755	INTEGER(iwp), INTENT(IN) :: number_end !< number of user-specified end levels for stretching
[4648]	756
[3065]	757	REAL(wp) :: delta_l !< absolute difference between l and l_rounded
	758	REAL(wp) :: delta_stretch_factor !< absolute difference between stretch_factor_1 and stretch_factor_2
[4648]	759	REAL(wp) :: delta_total_new !< sum of delta_l and delta_stretch_factor for the next iteration (should be as small as
	760	!< possible)
	761	REAL(wp) :: delta_total_old !< sum of delta_l and delta_stretch_factor for the last iteration
[3065]	762	REAL(wp) :: distance !< distance between dz_stretch_level_start and dz_stretch_level_end (stretching region)
[4648]	763	REAL(wp) :: l !< value that fulfil Eq. (5) in the paper mentioned above together with stretch_factor_1
	764	!< exactly
[3065]	765	REAL(wp) :: numerator !< numerator of the quotient
	766	REAL(wp) :: stretch_factor_1 !< stretching factor that fulfil Eq. (5) togehter with l exactly
	767	REAL(wp) :: stretch_factor_2 !< stretching factor that fulfil Eq. (6) togehter with l_rounded exactly
[4648]	768
	769	REAL(wp) :: dz_stretch_factor_array_2(9) = 1.08_wp !< Array that contains all stretch_factor_2 that belongs to
	770	!< stretch_factor_1
	771
	772
[3068]	773	l = 0
	774	DO n = 1, number_end
[4648]	775
[3068]	776	iterations = 1
[4648]	777	stretch_factor_1 = 1.0_wp
[4386]	778	stretch_factor_2 = 1.0_wp
	779	delta_total_old = 1.0_wp
[4648]	780
[4386]	781	!
	782	!-- First branch for stretching from rough to fine
[4648]	783	IF ( dz(n) > dz(n+1) ) THEN
	784	DO WHILE ( stretch_factor_1 >= stretch_factor_lower_limit )
	785
[4386]	786	stretch_factor_1 = 1.0_wp - iterations * stretch_factor_interval
[4648]	787	distance = ABS( dz_stretch_level_end(n) - dz_stretch_level_start(n) )
	788	numerator = distance * stretch_factor_1 / dz(n) + stretch_factor_1 - distance / dz(n)
	789
	790	IF ( numerator > 0.0_wp ) THEN
[4386]	791	l = LOG( numerator ) / LOG( stretch_factor_1 ) - 1.0_wp
[3068]	792	l_rounded = NINT( l )
	793	delta_l = ABS( l_rounded - l ) / l
	794	ENDIF
[4648]	795
[3068]	796	stretch_factor_2 = EXP( LOG( dz(n+1)/dz(n) ) / (l_rounded) )
[4648]	797
	798	delta_stretch_factor = ABS( stretch_factor_1 - stretch_factor_2 ) / stretch_factor_2
	799
[3068]	800	delta_total_new = delta_l + delta_stretch_factor
[3065]	801
	802	!
[4648]	803	!-- stretch_factor_1 is taken to guarantee that the stretching procedure ends as close as
	804	!-- possible to dz_stretch_level_end.
	805	!-- stretch_factor_2 would guarantee that the stretched dz(n) is equal to dz(n+1) after
	806	!-- l_rounded grid levels.
	807	IF (delta_total_new < delta_total_old) THEN
[3068]	808	dz_stretch_factor_array(n) = stretch_factor_1
	809	dz_stretch_factor_array_2(n) = stretch_factor_2
	810	delta_total_old = delta_total_new
	811	ENDIF
[4648]	812
[3068]	813	iterations = iterations + 1
[4648]	814
[3068]	815	ENDDO
[4386]	816
	817	!
	818	!-- Second branch for stretching from fine to rough
[4648]	819	ELSEIF ( dz(n) < dz(n+1) ) THEN
[4868]	820
[3068]	821	DO WHILE ( stretch_factor_1 <= stretch_factor_upper_limit )
[4648]	822
[4386]	823	stretch_factor_1 = 1.0_wp + iterations * stretch_factor_interval
[4648]	824	distance = ABS( dz_stretch_level_end(n) - dz_stretch_level_start(n) )
	825	numerator = distance * stretch_factor_1 / dz(n) + stretch_factor_1 - distance / dz(n)
	826
[4386]	827	l = LOG( numerator ) / LOG( stretch_factor_1 ) - 1.0_wp
[3068]	828	l_rounded = NINT( l )
	829	delta_l = ABS( l_rounded - l ) / l
[4648]	830
[3068]	831	stretch_factor_2 = EXP( LOG( dz(n+1)/dz(n) ) / (l_rounded) )
[3065]	832
[4648]	833	delta_stretch_factor = ABS( stretch_factor_1 - stretch_factor_2 ) / stretch_factor_2
	834
[3068]	835	delta_total_new = delta_l + delta_stretch_factor
[4648]	836
[3065]	837	!
[4648]	838	!-- stretch_factor_1 is taken to guarantee that the stretching procedure ends as close as
	839	!-- possible to dz_stretch_level_end.
	840	!-- stretch_factor_2 would guarantee that the stretched dz(n) is equal to dz(n+1) after
	841	!-- l_rounded grid levels.
	842	IF (delta_total_new < delta_total_old) THEN
[3068]	843	dz_stretch_factor_array(n) = stretch_factor_1
	844	dz_stretch_factor_array_2(n) = stretch_factor_2
	845	delta_total_old = delta_total_new
	846	ENDIF
[4648]	847
[3068]	848	iterations = iterations + 1
	849	ENDDO
[4648]	850
[3068]	851	ELSE
[4868]	852
[3068]	853	message_string= 'Two adjacent values of dz must be different'
	854	CALL message( 'init_grid', 'PA0228', 1, 2, 0, 6, 0 )
[4648]	855
[3068]	856	ENDIF
	857
	858	!
[4648]	859	!-- Check if also the second stretching factor fits into the allowed interval. If not, print a
	860	!-- warning for the user.
	861	IF ( dz_stretch_factor_array_2(n) < stretch_factor_lower_limit .OR. &
	862	dz_stretch_factor_array_2(n) > stretch_factor_upper_limit ) THEN
	863	WRITE( message_string, * ) 'stretch_factor_2 = ', dz_stretch_factor_array_2(n), &
	864	' which is', ' responsible for exactly reaching& dz =', &
	865	dz(n+1), 'after a specific amount of', &
	866	' grid levels& exceeds the upper', &
	867	' limit =', stretch_factor_upper_limit, &
	868	' &or lower limit = ', stretch_factor_lower_limit
[3068]	869	CALL message( 'init_grid', 'PA0499', 0, 1, 0, 6, 0 )
[4648]	870
[3068]	871	ENDIF
[4868]	872
[3068]	873	ENDDO
[4648]	874
[3065]	875	END SUBROUTINE calculate_stretching_factor
[4648]	876
	877
[3065]	878	! Description:
[4648]	879	! -------------------------------------------------------------------------------------------------!
	880	!> Set temporary topography flags and reference buildings on top of underlying orography.
	881	!--------------------------------------------------------------------------------------------------!
[2696]	882	SUBROUTINE process_topography( topo_3d )
	883
[4648]	884	USE arrays_3d, &
[2747]	885	ONLY: zu, zw
[2696]	886
[4648]	887	USE control_parameters, &
[4507]	888	ONLY: bc_lr_cyc, bc_ns_cyc, ocean_mode
[2696]	889
[4648]	890	USE exchange_horiz_mod, &
	891	ONLY: exchange_horiz_2d, exchange_horiz_int
[4457]	892
[4648]	893	USE indices, &
	894	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, nzt
[2696]	895
[4648]	896	USE netcdf_data_input_mod, &
	897	ONLY: buildings_f, building_id_f, building_type_f, &
	898	init_model, &
	899	input_pids_static, &
[2696]	900	terrain_height_f
	901
	902	USE kinds
	903
	904	USE pegrid
	905
	906	IMPLICIT NONE
	907
[4722]	908	INTEGER(iwp) :: dim_builds !< total number of buildings within the model domain
[2867]	909	INTEGER(iwp) :: i !< running index along x-direction
	910	INTEGER(iwp) :: j !< running index along y-direction
	911	INTEGER(iwp) :: k !< running index along z-direction with respect to numeric grid
	912	INTEGER(iwp) :: k2 !< running index along z-direction with respect to netcdf grid
	913	INTEGER(iwp) :: nr !< index variable indication maximum terrain height for respective building ID
	914	INTEGER(iwp) :: num_build !< counter for number of buildings
	915	INTEGER(iwp) :: topo_top_index !< orography top index, used to map 3D buildings onto terrain
[2696]	916
[4444]	917	#if defined( __parallel )
[2696]	918	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: displace_dum !< displacements of start addresses, used for MPI_ALLGATHERV
[4444]	919	#endif
[2696]	920	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids !< building IDs on entire model domain
[4648]	921	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_final !< building IDs on entire model domain, multiple occurences are
	922	!< sorted out
[2696]	923	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_final_tmp !< temporary array used for resizing
	924	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_l !< building IDs on local subdomain
	925	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: build_ids_l_tmp !< temporary array used to resize array of building IDs
	926
	927	INTEGER(iwp), DIMENSION(0:numprocs-1) :: num_buildings !< number of buildings with different ID on entire model domain
	928	INTEGER(iwp), DIMENSION(0:numprocs-1) :: num_buildings_l !< number of buildings with different ID on local subdomain
	929
[4648]	930	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo_3d !< input array for 3D topography and dummy array for setting
	931	!< "outer"-flags
[2696]	932
[4648]	933	REAL(wp) :: ocean_offset !< offset to consider inverse vertical coordinate at topography
	934	!< definition
	935	REAL(wp) :: oro_min = 0.0_wp !< minimum terrain height in entire model domain, used to reference
	936	!< terrain to zero
[2696]	937	REAL(wp), DIMENSION(:), ALLOCATABLE :: oro_max !< maximum terrain height occupied by an building with certain id
[4648]	938	REAL(wp), DIMENSION(:), ALLOCATABLE :: oro_max_l !< maximum terrain height occupied by an building with certain id,
	939	!< on local subdomain
[2696]	940
	941	!
[4648]	942	!-- Reference lowest terrain height to zero. This ensures that first, non-required gird levels
	943	!-- (those which lie entirely below the minimum orography) are avoided, and second, that also
	944	!-- negative orography can be used within the input file.
	945	!-- Please note, in case of a nested run, the global minimum from all parent and childs needs to be
	946	!-- removed to avoid steep edges at the child-domain boundaries.
[3103]	947	IF ( input_pids_static ) THEN
[4648]	948
	949	#if defined( __parallel )
	950	CALL MPI_ALLREDUCE( MINVAL( terrain_height_f%var ), oro_min, 1, MPI_REAL, MPI_MIN, &
	951	MPI_COMM_WORLD, ierr )
[3200]	952	#else
	953	oro_min = MINVAL( terrain_height_f%var )
	954	#endif
[3103]	955	terrain_height_f%var = terrain_height_f%var - oro_min
[4507]	956	!
	957	!-- Update reference height used within output files
	958	init_model%origin_z = init_model%origin_z + oro_min
[4691]	959	!
	960	!-- ASCII topography branch. In this case, in contrast to the static driver input, topography is
	961	!-- assumed to be building; thus the minimum building height is substracted from the building array.
	962	ELSE
	963	#if defined( __parallel )
	964	CALL MPI_ALLREDUCE( MINVAL( buildings_f%var_2d ), oro_min, 1, MPI_REAL, MPI_MIN, &
	965	MPI_COMM_WORLD, ierr )
	966	#else
	967	oro_min = MINVAL( buildings_f%var_2d )
	968	#endif
	969	buildings_f%var_2d = buildings_f%var_2d - oro_min
	970	!
	971	!-- Update reference height used within output files
	972	init_model%origin_z = init_model%origin_z + oro_min
[4648]	973	ENDIF
	974
[3103]	975	!
[4648]	976	!-- In the following, buildings and orography are further preprocessed before they are mapped on the
	977	!-- LES grid.
	978	!-- Buildings are mapped on top of the orography by maintaining the roof shape of the building. This
	979	!-- can be achieved by referencing building on top of the maximum terrain height within the area
	980	!-- occupied by the respective building. As buildings and terrain height are defined PE-wise,
	981	!-- parallelization of this referencing is required (a building can be distributed between different
	982	!-- PEs).
	983	!-- In a first step, determine the number of buildings with different building id on each PE. In a
	984	!-- next step, all building ids are gathered into one array which is present to all PEs. For each
	985	!-- building ID, the maximum terrain height occupied by the respective building is computed and
	986	!-- distributed to each PE.
	987	!-- Finally, for each building id and its respective reference orography, builidings are mapped on
	988	!-- top.
	989	!--
	990	!-- First, pre-set topography flags, bit 1 indicates orography, bit 2 buildings classify the
	991	!-- respective surfaces.
[2696]	992	topo_3d = IBSET( topo_3d, 0 )
	993	topo_3d(nzb,:,:) = IBCLR( topo_3d(nzb,:,:), 0 )
	994	!
[4648]	995	!-- In order to map topography on PALM grid also in case of ocean simulations, pre-calculate an
	996	!-- offset value.
[3294]	997	ocean_offset = MERGE( zw(0), 0.0_wp, ocean_mode )
[3051]	998	!
[4648]	999	!-- Reference buildings on top of orography. This is not necessary if topography is read from ASCII
	1000	!-- file as no distinction between buildings and terrain height can be made. Moreover, this is also
	1001	!-- not necessary if urban-surface and land-surface model are used at the same time.
[2897]	1002	IF ( input_pids_static ) THEN
	1003
[4648]	1004	IF ( buildings_f%from_file ) THEN
[2897]	1005	num_buildings_l = 0
	1006	num_buildings = 0
[2696]	1007	!
[4648]	1008	!-- Allocate at least one element for building ids and give it an inital negative value that
	1009	!-- will be overwritten later. This, however, is necessary in case there all IDs in the model
	1010	!-- domain are fill values.
[2897]	1011	ALLOCATE( build_ids_l(1) )
[4648]	1012	build_ids_l = -1
[2897]	1013	DO i = nxl, nxr
	1014	DO j = nys, nyn
	1015	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1016	IF ( num_buildings_l(myid) > 0 ) THEN
[4648]	1017	IF ( ANY( building_id_f%var(j,i) == build_ids_l ) ) THEN
[2897]	1018	CYCLE
	1019	ELSE
	1020	num_buildings_l(myid) = num_buildings_l(myid) + 1
[2696]	1021	!
	1022	!-- Resize array with different local building ids
	1023	ALLOCATE( build_ids_l_tmp(1:SIZE(build_ids_l)) )
	1024	build_ids_l_tmp = build_ids_l
	1025	DEALLOCATE( build_ids_l )
	1026	ALLOCATE( build_ids_l(1:num_buildings_l(myid)) )
[4648]	1027	build_ids_l(1:num_buildings_l(myid)-1) = &
	1028	build_ids_l_tmp(1:num_buildings_l(myid)-1)
[2696]	1029	build_ids_l(num_buildings_l(myid)) = building_id_f%var(j,i)
	1030	DEALLOCATE( build_ids_l_tmp )
	1031	ENDIF
	1032	!
[4648]	1033	!-- First occuring building id on PE
	1034	ELSE
[2897]	1035	num_buildings_l(myid) = num_buildings_l(myid) + 1
	1036	build_ids_l(1) = building_id_f%var(j,i)
	1037	ENDIF
[2696]	1038	ENDIF
[2897]	1039	ENDDO
[2696]	1040	ENDDO
	1041	!
[4648]	1042	!-- Determine number of different building ids for the entire domain
	1043	#if defined( __parallel )
	1044	CALL MPI_ALLREDUCE( num_buildings_l, num_buildings, numprocs, MPI_INTEGER, MPI_SUM, &
	1045	comm2d, ierr )
[2696]	1046	#else
[2897]	1047	num_buildings = num_buildings_l
[2696]	1048	#endif
	1049	!
[4648]	1050	!-- Gather all buildings ids on each PEs.
	1051	!-- First, allocate array encompassing all building ids in model domain.
[2897]	1052	ALLOCATE( build_ids(1:SUM(num_buildings)) )
[4648]	1053	#if defined( __parallel )
[2696]	1054	!
[4648]	1055	!-- Allocate array for displacements.
	1056	!-- As each PE may has a different number of buildings, so that the block sizes send by each
	1057	!-- PE may not be equal. Hence, information about the respective displacement is required,
	1058	!-- indicating the respective adress where each MPI-task writes into the receive buffer array.
[2897]	1059	ALLOCATE( displace_dum(0:numprocs-1) )
	1060	displace_dum(0) = 0
	1061	DO i = 1, numprocs-1
	1062	displace_dum(i) = displace_dum(i-1) + num_buildings(i-1)
	1063	ENDDO
[2696]	1064
[4648]	1065	CALL MPI_ALLGATHERV( build_ids_l(1:num_buildings_l(myid)), num_buildings(myid), &
	1066	MPI_INTEGER, build_ids, num_buildings, displace_dum, MPI_INTEGER, &
	1067	comm2d, ierr )
[2696]	1068
[2897]	1069	DEALLOCATE( displace_dum )
[2696]	1070
	1071	#else
[2897]	1072	build_ids = build_ids_l
[2696]	1073	#endif
	1074
	1075	!
[4648]	1076	!-- Note, in parallel mode building ids can occure mutliple times, as each PE has send its own
	1077	!-- ids. Therefore, sort out building ids which appear more than one time.
[2897]	1078	num_build = 0
	1079	DO nr = 1, SIZE(build_ids)
[2696]	1080
[2897]	1081	IF ( ALLOCATED(build_ids_final) ) THEN
[4144]	1082	IF ( ANY( build_ids(nr) == build_ids_final ) ) THEN
[2897]	1083	CYCLE
	1084	ELSE
	1085	num_build = num_build + 1
	1086	!
	1087	!-- Resize
	1088	ALLOCATE( build_ids_final_tmp(1:num_build) )
	1089	build_ids_final_tmp(1:num_build-1) = build_ids_final(1:num_build-1)
	1090	DEALLOCATE( build_ids_final )
	1091	ALLOCATE( build_ids_final(1:num_build) )
	1092	build_ids_final(1:num_build-1) = build_ids_final_tmp(1:num_build-1)
	1093	build_ids_final(num_build) = build_ids(nr)
	1094	DEALLOCATE( build_ids_final_tmp )
[4648]	1095	ENDIF
[2696]	1096	ELSE
	1097	num_build = num_build + 1
	1098	ALLOCATE( build_ids_final(1:num_build) )
	1099	build_ids_final(num_build) = build_ids(nr)
[2897]	1100	ENDIF
	1101	ENDDO
[2696]	1102
	1103	!
[4648]	1104	!-- Determine maximumum terrain height occupied by the respective building and temporalily
[4722]	1105	!-- store on oro_max. Before, check whether any buildings are defined within the domain.
	1106	IF ( ALLOCATED( build_ids_final ) ) THEN
	1107	dim_builds = SIZE(build_ids_final)
	1108	ELSE
	1109	dim_builds = 0
	1110	ENDIF
	1111
	1112	ALLOCATE( oro_max_l(1:dim_builds) )
	1113	ALLOCATE( oro_max(1:dim_builds) )
[2897]	1114	oro_max_l = 0.0_wp
[2696]	1115
[4722]	1116	DO nr = 1, dim_builds
[4648]	1117	oro_max_l(nr) = MAXVAL( MERGE( terrain_height_f%var(nys:nyn,nxl:nxr), &
	1118	0.0_wp, &
	1119	building_id_f%var(nys:nyn,nxl:nxr) == &
	1120	build_ids_final(nr) ) )
[2897]	1121	ENDDO
[4648]	1122
	1123	#if defined( __parallel )
[4722]	1124	IF ( dim_builds >= 1 ) THEN
[4648]	1125	CALL MPI_ALLREDUCE( oro_max_l, oro_max, SIZE( oro_max ), MPI_REAL, MPI_MAX, comm2d, &
	1126	ierr )
[2897]	1127	ENDIF
[2696]	1128	#else
[2897]	1129	oro_max = oro_max_l
[2696]	1130	#endif
[3051]	1131	!
[4648]	1132	!-- Finally, determine discrete grid height of maximum orography occupied by a building. Use
	1133	!-- all-or-nothing approach, i.e. if terrain exceeds the scalar level the grid box is fully
	1134	!-- terrain and the maximum terrain is set to the zw level.
	1135	!-- terrain or
[3051]	1136	oro_max_l = 0.0
[4722]	1137	DO nr = 1, dim_builds
[3051]	1138	DO k = nzb, nzt
[4648]	1139	IF ( zu(k) - ocean_offset <= oro_max(nr) ) oro_max_l(nr) = zw(k) - ocean_offset
[3051]	1140	ENDDO
[3142]	1141	oro_max(nr) = oro_max_l(nr)
[3051]	1142	ENDDO
[2897]	1143	ENDIF
[2696]	1144	!
[4245]	1145	!-- Allocate array for storing terrain height under buildings
	1146	IF ( buildings_f%from_file ) THEN
	1147	ALLOCATE( buildings_f%oro_max(nysg:nyng,nxlg:nxrg) )
	1148	buildings_f%oro_max = buildings_f%fill1
	1149	END IF
	1150	!
[4648]	1151	!-- Map orography as well as buildings onto grid.
[2696]	1152	DO i = nxl, nxr
	1153	DO j = nys, nyn
[2867]	1154	topo_top_index = 0
[3142]	1155	!
	1156	!-- Obtain index in global building_id array
	1157	IF ( buildings_f%from_file ) THEN
	1158	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1159	!
[4648]	1160	!-- Determine index where maximum terrain height occupied by the respective building
	1161	!-- height is stored.
	1162	nr = MINLOC( ABS( build_ids_final - building_id_f%var(j,i) ), DIM=1 )
[4245]	1163	!
	1164	!-- Save grid-indexed oro_max
	1165	buildings_f%oro_max(j,i) = oro_max(nr)
[3142]	1166	ENDIF
	1167	ENDIF
[2696]	1168	DO k = nzb, nzt
	1169	!
[4648]	1170	!-- In a first step, if grid point is below or equal the given terrain height, grid
	1171	!-- point is flagged to be of type natural.
	1172	!-- Please note, in case there is also a building which is lower than the vertical grid
	1173	!-- spacing, initialization of surface attributes will not be correct as given surface
	1174	!-- information will not be in accordance to the classified grid points.
[4159]	1175	!-- Hence, in this case, also a building flag.
[2747]	1176	IF ( zu(k) - ocean_offset <= terrain_height_f%var(j,i) ) THEN
[4189]	1177	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
	1178	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1179	topo_top_index = k ! topo_top_index + 1
[2696]	1180	ENDIF
	1181	!
[4648]	1182	!-- Set building grid points. Here, only consider 2D buildings.
	1183	!-- 3D buildings require separate treatment.
[2897]	1184	IF ( buildings_f%from_file .AND. buildings_f%lod == 1 ) THEN
[4159]	1185	!
[4648]	1186	!-- Fill-up the terrain to the level of maximum orography within the building-covered
	1187	!-- area.
[4159]	1188	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1189	!
[4648]	1190	!-- Note, oro_max is always on zw level
[4159]	1191	IF ( zu(k) - ocean_offset < oro_max(nr) ) THEN
[2696]	1192	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4159]	1193	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
[4648]	1194	ELSEIF ( zu(k) - ocean_offset <= oro_max(nr) + buildings_f%var_2d(j,i) ) THEN
[4159]	1195	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[2696]	1196	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1197	ENDIF
	1198	ENDIF
	1199	ENDIF
	1200	ENDDO
	1201	!
[4648]	1202	!-- Special treatment for non grid-resolved buildings. This case, the uppermost terrain
	1203	!-- grid point is flagged as building as well, even though no building exists at all.
	1204	!-- However, the surface element will be identified as urban-surface and the input data
	1205	!-- provided by the drivers is consistent to the surface classification. Else, all non
	1206	!-- grid-resolved buildings would vanish and identified as terrain grid points, which,
	1207	!-- however, won't be consistent with the input data.
[4159]	1208	IF ( buildings_f%from_file .AND. buildings_f%lod == 1 ) THEN
	1209	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1210	DO k = nzb, nzt
	1211	IF( zw(k) - ocean_offset == oro_max(nr) ) THEN
	1212	IF ( buildings_f%var_2d(j,i) <= zu(k+1) - zw(k) ) THEN
	1213	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1214	ENDIF
	1215	ENDIF
	1216	ENDDO
	1217	ENDIF
	1218	ENDIF
	1219	!
[4648]	1220	!-- Map 3D buildings onto terrain height.
	1221	!-- In case of any slopes, map building on top of maximum terrain height covered by the
	1222	!-- building. In other words, extend building down to the respective local terrain-surface
	1223	!-- height.
[2897]	1224	IF ( buildings_f%from_file .AND. buildings_f%lod == 2 ) THEN
[2696]	1225	IF ( building_id_f%var(j,i) /= building_id_f%fill ) THEN
	1226	!
[4648]	1227	!-- Extend building down to the terrain surface, i.e. fill-up surface irregularities
	1228	!-- below a building. Note, oro_max is already a discrete height according to the
	1229	!-- all-or-nothing approach, i.e. grid box is either topography or atmosphere,
[3051]	1230	!-- terrain top is defined at upper bound of the grid box.
[4648]	1231	!-- Hence, check for zw in this case.
	1232	!-- Note, do this only for buildings which are surface mounted, i.e. building types
	1233	!-- 1-6. Below bridges, which are represented exclusively by building type 7, terrain
	1234	!-- shape should be maintained.
[3855]	1235	IF ( building_type_f%from_file ) THEN
	1236	IF ( building_type_f%var(j,i) /= 7 ) THEN
[4648]	1237	DO k = topo_top_index + 1, nzt + 1
[4159]	1238	IF ( zu(k) - ocean_offset <= oro_max(nr) ) THEN
[3855]	1239	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4159]	1240	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
[3855]	1241	ENDIF
[4648]	1242	ENDDO
	1243	!
	1244	!-- After surface irregularities are smoothen, determine lower start index
	1245	!-- where building starts.
[3855]	1246	DO k = nzb, nzt
[4648]	1247	IF ( zu(k) - ocean_offset <= oro_max(nr) ) topo_top_index = k
[3855]	1248	ENDDO
	1249	ENDIF
[3115]	1250	ENDIF
[3051]	1251	!
	1252	!-- Finally, map building on top.
[2867]	1253	k2 = 0
	1254	DO k = topo_top_index, nzt + 1
[2796]	1255	IF ( k2 <= buildings_f%nz-1 ) THEN
[2696]	1256	IF ( buildings_f%var_3d(k2,j,i) == 1 ) THEN
	1257	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
	1258	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1259	ENDIF
	1260	ENDIF
	1261	k2 = k2 + 1
	1262	ENDDO
	1263	ENDIF
	1264	ENDIF
	1265	ENDDO
	1266	ENDDO
	1267	!
[4648]	1268	!-- Horizontal exchange the oro_max array, which is required to for initialization of
	1269	!-- building-surface properties.
[4265]	1270	IF ( ALLOCATED( buildings_f%oro_max ) ) THEN
[4457]	1271	CALL exchange_horiz_2d( buildings_f%oro_max(:,:) )
[4265]	1272	ENDIF
[4245]	1273	!
[2696]	1274	!-- Deallocate temporary arrays required for processing and reading data
	1275	IF ( ALLOCATED( oro_max ) ) DEALLOCATE( oro_max )
	1276	IF ( ALLOCATED( oro_max_l ) ) DEALLOCATE( oro_max_l )
	1277	IF ( ALLOCATED( build_ids_final ) ) DEALLOCATE( build_ids_final )
	1278	!
[4648]	1279	!-- Topography input via ASCII format.
[2696]	1280	ELSE
[4868]	1281
	1282	ocean_offset = MERGE( zw(0), 0.0_wp, ocean_mode )
[4159]	1283	!
[4648]	1284	!-- Initialize topography bit 0 (indicates obstacle) everywhere to zero and clear all grid points
	1285	!-- at nzb, where alway a surface is defined.
	1286	!-- Further, set also bit 1 (indicates terrain) at nzb, which is further used for masked data
	1287	!-- output and further processing. Note, in the ASCII case no distinction is made between
	1288	!-- buildings and terrain, so that setting of bit 1 and 2 at the same time has no effect.
[2696]	1289	topo_3d = IBSET( topo_3d, 0 )
	1290	topo_3d(nzb,:,:) = IBCLR( topo_3d(nzb,:,:), 0 )
[4159]	1291	topo_3d(nzb,:,:) = IBSET( topo_3d(nzb,:,:), 1 )
[2696]	1292	DO i = nxl, nxr
	1293	DO j = nys, nyn
	1294	DO k = nzb, nzt
[3538]	1295	!
[4648]	1296	!-- Flag topography for all grid points which are below the local topography height.
	1297	!-- Note, each topography is flagged as building (bit 2) as well as terrain (bit 1) in
	1298	!-- order to employ urban-surface as well as land-surface model.
[2747]	1299	IF ( zu(k) - ocean_offset <= buildings_f%var_2d(j,i) ) THEN
[4189]	1300	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4630]	1301	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 1 )
	1302	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
[2696]	1303	ENDIF
	1304	ENDDO
	1305	ENDDO
	1306	ENDDO
[4868]	1307
[2696]	1308	ENDIF
	1309
	1310	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
	1311
	1312	IF ( .NOT. bc_ns_cyc ) THEN
	1313	IF ( nys == 0 ) topo_3d(:,-1,:) = topo_3d(:,0,:)
	1314	IF ( nyn == ny ) topo_3d(:,ny+1,:) = topo_3d(:,ny,:)
	1315	ENDIF
	1316
	1317	IF ( .NOT. bc_lr_cyc ) THEN
	1318	IF ( nxl == 0 ) topo_3d(:,:,-1) = topo_3d(:,:,0)
[4648]	1319	IF ( nxr == nx ) topo_3d(:,:,nx+1) = topo_3d(:,:,nx)
[2696]	1320	ENDIF
	1321
	1322	END SUBROUTINE process_topography
	1323
	1324
	1325	! Description:
[4648]	1326	! -------------------------------------------------------------------------------------------------!
	1327	!> Filter topography, i.e. fill holes resolved by only one grid point.
	1328	!> Such holes are suspected to lead to velocity blow-ups as continuity equation on discrete grid
	1329	!> cannot be fulfilled in such case.
	1330	!--------------------------------------------------------------------------------------------------!
[2696]	1331	SUBROUTINE filter_topography( topo_3d )
	1332
[4648]	1333	USE control_parameters, &
[2696]	1334	ONLY: bc_lr_cyc, bc_ns_cyc, message_string
	1335
[4648]	1336	USE exchange_horiz_mod, &
[4457]	1337	ONLY: exchange_horiz_int, exchange_horiz_2d_byte, exchange_horiz_2d_int
	1338
[4648]	1339	USE indices, &
[2696]	1340	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, nzt
	1341
[4648]	1342	USE netcdf_data_input_mod, &
	1343	ONLY: building_id_f, building_type_f
[2696]	1344
	1345	USE pegrid
	1346
	1347	IMPLICIT NONE
	1348
	1349	INTEGER(iwp) :: i !< running index along x-direction
	1350	INTEGER(iwp) :: j !< running index along y-direction
	1351	INTEGER(iwp) :: k !< running index along z-direction
[4648]	1352	INTEGER(iwp) :: num_hole !< number of holes (in topography) resolved by only one grid point
	1353	INTEGER(iwp) :: num_hole_l !< number of holes (in topography) resolved by only one grid point on local PE
[2696]	1354	INTEGER(iwp) :: num_wall !< number of surrounding vertical walls for a single grid point
	1355
[4868]	1356	INTEGER(iwp), DIMENSION(:,:,:), ALLOCATABLE :: topo_tmp !< temporary 3D-topography used to fill holes
	1357	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo_3d !< 3D-topography array merging buildings and
	1358	!< orography
[4648]	1359
	1360	LOGICAL :: filled = .FALSE. !< flag indicating if holes were filled
	1361
[2696]	1362	!
[4648]	1363	!-- Before checking for holes, set lateral boundary conditions for
[2696]	1364	!-- topography. After hole-filling, boundary conditions must be set again.
[4648]	1365	!-- Several iterations are performed, in order to fill holes which might
[2696]	1366	!-- emerge by the filling-algorithm itself.
	1367	ALLOCATE( topo_tmp(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	1368	topo_tmp = 0
	1369
	1370	num_hole = 99999
[4648]	1371	DO WHILE ( num_hole > 0 )
[2696]	1372
[4648]	1373	num_hole = 0
[2696]	1374	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
[2955]	1375	!
[4648]	1376	!-- Exchange also building ID and type. Note, building_type is an one-byte variable.
	1377	IF ( building_id_f%from_file ) &
[2955]	1378	CALL exchange_horiz_2d_int( building_id_f%var, nys, nyn, nxl, nxr, nbgp )
[4648]	1379	IF ( building_type_f%from_file ) &
[3763]	1380	CALL exchange_horiz_2d_byte( building_type_f%var, nys, nyn, nxl, nxr, nbgp )
[2696]	1381
	1382	topo_tmp = topo_3d
	1383	!
[4648]	1384	!-- In case of non-cyclic lateral boundaries, assume lateral boundary to be a solid wall. Thus,
	1385	!-- intermediate spaces of one grid point between boundary and some topographic structure will be
	1386	!-- filled.
[2696]	1387	IF ( .NOT. bc_ns_cyc ) THEN
	1388	IF ( nys == 0 ) topo_tmp(:,-1,:) = IBCLR( topo_tmp(:,0,:), 0 )
	1389	IF ( nyn == ny ) topo_tmp(:,ny+1,:) = IBCLR( topo_tmp(:,ny,:), 0 )
	1390	ENDIF
	1391
	1392	IF ( .NOT. bc_lr_cyc ) THEN
	1393	IF ( nxl == 0 ) topo_tmp(:,:,-1) = IBCLR( topo_tmp(:,:,0), 0 )
[4648]	1394	IF ( nxr == nx ) topo_tmp(:,:,nx+1) = IBCLR( topo_tmp(:,:,nx), 0 )
[2696]	1395	ENDIF
	1396
	1397	num_hole_l = 0
	1398	DO i = nxl, nxr
	1399	DO j = nys, nyn
	1400	DO k = nzb+1, nzt
	1401	IF ( BTEST( topo_tmp(k,j,i), 0 ) ) THEN
	1402	num_wall = 0
[4648]	1403	IF ( .NOT. BTEST( topo_tmp(k,j-1,i), 0 ) ) num_wall = num_wall + 1
	1404	IF ( .NOT. BTEST( topo_tmp(k,j+1,i), 0 ) ) num_wall = num_wall + 1
	1405	IF ( .NOT. BTEST( topo_tmp(k,j,i-1), 0 ) ) num_wall = num_wall + 1
	1406	IF ( .NOT. BTEST( topo_tmp(k,j,i+1), 0 ) ) num_wall = num_wall + 1
	1407	IF ( .NOT. BTEST( topo_tmp(k-1,j,i), 0 ) ) num_wall = num_wall + 1
	1408	IF ( .NOT. BTEST( topo_tmp(k+1,j,i), 0 ) ) num_wall = num_wall + 1
[2696]	1409
	1410	IF ( num_wall >= 4 ) THEN
	1411	num_hole_l = num_hole_l + 1
	1412	!
[4648]	1413	!-- Clear flag 0 and set special flag ( bit 4) to indicate that new topography
	1414	!-- point is a result of filtering process.
[2696]	1415	topo_3d(k,j,i) = IBCLR( topo_3d(k,j,i), 0 )
[4314]	1416	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 4 )
[2696]	1417	!
[4648]	1418	!-- If filled grid point is occupied by a building, classify it as building grid
	1419	!-- point.
[2696]	1420	IF ( building_type_f%from_file ) THEN
[4648]	1421	IF ( building_type_f%var(j,i) /= building_type_f%fill .OR. &
	1422	building_type_f%var(j+1,i) /= building_type_f%fill .OR. &
	1423	building_type_f%var(j-1,i) /= building_type_f%fill .OR. &
	1424	building_type_f%var(j,i+1) /= building_type_f%fill .OR. &
	1425	building_type_f%var(j,i-1) /= building_type_f%fill ) THEN
[2696]	1426	!
	1427	!-- Set flag indicating building surfaces
	1428	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 2 )
	1429	!
[4648]	1430	!-- Set building_type and ID at this position if not already set. This is
	1431	!-- required for proper initialization of urban-surface energy balance
[2696]	1432	!-- solver.
[4648]	1433	IF ( building_type_f%var(j,i) == building_type_f%fill ) THEN
[2696]	1434
[4648]	1435	IF ( building_type_f%var(j+1,i) /= building_type_f%fill ) THEN
	1436	building_type_f%var(j,i) = building_type_f%var(j+1,i)
	1437	building_id_f%var(j,i) = building_id_f%var(j+1,i)
	1438	ELSEIF ( building_type_f%var(j-1,i) /= building_type_f%fill ) THEN
	1439	building_type_f%var(j,i) = building_type_f%var(j-1,i)
	1440	building_id_f%var(j,i) = building_id_f%var(j-1,i)
	1441	ELSEIF ( building_type_f%var(j,i+1) /= building_type_f%fill ) THEN
	1442	building_type_f%var(j,i) = building_type_f%var(j,i+1)
	1443	building_id_f%var(j,i) = building_id_f%var(j,i+1)
	1444	ELSEIF ( building_type_f%var(j,i-1) /= building_type_f%fill ) THEN
	1445	building_type_f%var(j,i) = building_type_f%var(j,i-1)
	1446	building_id_f%var(j,i) = building_id_f%var(j,i-1)
[2696]	1447	ENDIF
	1448	ENDIF
	1449	ENDIF
	1450	ENDIF
	1451	!
[4648]	1452	!-- If filled grid point is already classified as building everything is fine,
	1453	!-- else classify this grid point as natural type grid point. This case, values
	1454	!-- for the surface type are already set.
[2696]	1455	IF ( .NOT. BTEST( topo_3d(k,j,i), 2 ) ) THEN
	1456	topo_3d(k,j,i) = IBSET( topo_3d(k,j,i), 1 )
	1457	ENDIF
	1458	ENDIF
	1459	ENDIF
	1460	ENDDO
	1461	ENDDO
	1462	ENDDO
	1463	!
	1464	!-- Count the total number of holes, required for informative message.
	1465	#if defined( __parallel )
[4648]	1466	CALL MPI_ALLREDUCE( num_hole_l, num_hole, 1, MPI_INTEGER, MPI_SUM, comm2d, ierr )
[2696]	1467	#else
	1468	num_hole = num_hole_l
[4648]	1469	#endif
[2893]	1470	IF ( num_hole > 0 .AND. .NOT. filled ) filled = .TRUE.
[2696]	1471
[2893]	1472	ENDDO
[2696]	1473	!
[2893]	1474	!-- Create an informative message if any holes were filled.
	1475	IF ( filled ) THEN
[4648]	1476	WRITE( message_string, * ) 'Topography was filtered, i.e. holes ' // &
	1477	'resolved by only one grid point ' // &
[2893]	1478	'were filled during initialization.'
	1479	CALL message( 'init_grid', 'PA0430', 0, 0, 0, 6, 0 )
	1480	ENDIF
[2696]	1481
	1482	DEALLOCATE( topo_tmp )
	1483	!
[4648]	1484	!-- Finally, exchange topo_3d array again and if necessary set Neumann boundary condition in case of
	1485	!-- non-cyclic lateral boundaries.
[2696]	1486	CALL exchange_horiz_int( topo_3d, nys, nyn, nxl, nxr, nzt, nbgp )
	1487
	1488	IF ( .NOT. bc_ns_cyc ) THEN
	1489	IF ( nys == 0 ) topo_3d(:,-1,:) = topo_3d(:,0,:)
	1490	IF ( nyn == ny ) topo_3d(:,ny+1,:) = topo_3d(:,ny,:)
	1491	ENDIF
	1492
	1493	IF ( .NOT. bc_lr_cyc ) THEN
	1494	IF ( nxl == 0 ) topo_3d(:,:,-1) = topo_3d(:,:,0)
[4648]	1495	IF ( nxr == nx ) topo_3d(:,:,nx+1) = topo_3d(:,:,nx)
[2696]	1496	ENDIF
[2955]	1497	!
	1498	!-- Exchange building ID and type. Note, building_type is an one-byte variable.
[4648]	1499	IF ( building_id_f%from_file ) &
[2955]	1500	CALL exchange_horiz_2d_int( building_id_f%var, nys, nyn, nxl, nxr, nbgp )
[4648]	1501	IF ( building_type_f%from_file ) &
[3763]	1502	CALL exchange_horiz_2d_byte( building_type_f%var, nys, nyn, nxl, nxr, nbgp )
[2696]	1503
	1504	END SUBROUTINE filter_topography
	1505
	1506
	1507	! Description:
[4648]	1508	! -------------------------------------------------------------------------------------------------!
	1509	!> Reads topography information from file or sets generic topography. Moreover, all
	1510	!> topography-relevant topography arrays are initialized, and grid flags are set.
	1511	!--------------------------------------------------------------------------------------------------!
[2696]	1512	SUBROUTINE init_topo( topo )
	1513
[4648]	1514	USE arrays_3d, &
[2696]	1515	ONLY: zw
[4648]	1516
	1517	USE control_parameters, &
	1518	ONLY: bc_lr_cyc, bc_ns_cyc, building_height, building_length_x, building_length_y, &
	1519	building_wall_left, building_wall_south, canyon_height, canyon_wall_left, &
	1520	canyon_wall_south, canyon_width_x, canyon_width_y, dp_level_ind_b, dz, &
	1521	message_string, topography, topography_grid_convention, tunnel_height, &
	1522	tunnel_length, tunnel_width_x, tunnel_width_y, tunnel_wall_depth
	1523
	1524	USE exchange_horiz_mod, &
[4457]	1525	ONLY: exchange_horiz_int
	1526
[4648]	1527	USE grid_variables, &
[2696]	1528	ONLY: dx, dy
[4648]	1529
	1530	USE indices, &
	1531	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, nzb, nzt
	1532
[2696]	1533	USE kinds
	1534
[4648]	1535	USE netcdf_data_input_mod, &
	1536	ONLY: buildings_f, terrain_height_f
	1537
[2696]	1538	USE pegrid
	1539
	1540	IMPLICIT NONE
	1541
[4386]	1542	INTEGER(iwp) :: bh !< temporary vertical index of building height
[4648]	1543	INTEGER(iwp) :: ch !< temporary vertical index for canyon height
	1544	INTEGER(iwp) :: hv_in !< heavyside function to model inner tunnel surface
	1545	INTEGER(iwp) :: i !< index variable along x
[4386]	1546	INTEGER(iwp) :: index_left_bwall !< index for left building wall
[4648]	1547	INTEGER(iwp) :: index_north_bwall !< index for north building wall
[4386]	1548	INTEGER(iwp) :: index_right_bwall !< index for right building wall
	1549	INTEGER(iwp) :: index_south_bwall !< index for south building wall
	1550	INTEGER(iwp) :: index_left_cwall !< index for left canyon wall
[4648]	1551	INTEGER(iwp) :: index_north_cwall !< index for north canyon wall
[4386]	1552	INTEGER(iwp) :: index_right_cwall !< index for right canyon wall
	1553	INTEGER(iwp) :: index_south_cwall !< index for south canyon wall
	1554	INTEGER(iwp) :: j !< index variable along y
	1555	INTEGER(iwp) :: k !< index variable along z
[4648]	1556	INTEGER(iwp) :: ngp_bx !< grid point number of building size along x
	1557	INTEGER(iwp) :: ngp_by !< grid point number of building size along y
	1558	INTEGER(iwp) :: ngp_cx !< grid point number of canyon size along x
	1559	INTEGER(iwp) :: ngp_cy !< grid point number of canyon size along y
	1560	INTEGER(iwp) :: hv_out !< heavyside function to model outer tunnel surface
	1561	INTEGER(iwp) :: td !< tunnel wall depth
	1562	INTEGER(iwp) :: th !< height of outer tunnel wall
	1563	INTEGER(iwp) :: txe_in !< end position of inner tunnel wall in x
[4386]	1564	INTEGER(iwp) :: txe_out !< end position of outer tunnel wall in x
[4648]	1565	INTEGER(iwp) :: txs_in !< start position of inner tunnel wall in x
[4386]	1566	INTEGER(iwp) :: txs_out !< start position of outer tunnel wall in x
[4648]	1567	INTEGER(iwp) :: tye_in !< end position of inner tunnel wall in y
[4386]	1568	INTEGER(iwp) :: tye_out !< end position of outer tunnel wall in y
[4648]	1569	INTEGER(iwp) :: tys_in !< start position of inner tunnel wall in y
[4386]	1570	INTEGER(iwp) :: tys_out !< start position of outer tunnel wall in y
[2696]	1571
	1572	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nzb_local !< index for topography top at cell-center
[4648]	1573	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo !< input array for 3D topography and dummy array for setting
	1574	!< "outer"-flags
[2696]	1575	!
[4648]	1576	!-- Check for correct setting of the namelist parameter topography. If topography information is
	1577	!-- read from file but topography = 'flat', initialization does not work properly.
	1578	IF ( ( buildings_f%from_file .OR. terrain_height_f%from_file ) .AND. &
[4189]	1579	TRIM( topography ) /= 'read_from_file' ) THEN
[4648]	1580	message_string = 'If topography information is provided (via ' // &
	1581	'Netcdf or ASCII input) topography = ' // &
[4189]	1582	'"read_from_file" is required.'
[4648]	1583	CALL message( 'init_grid', 'PA0437', 1, 2, 0, 6, 0 )
[4189]	1584	ENDIF
	1585	!
[1]	1586	!-- Set outer and inner index arrays for non-flat topography.
[4648]	1587	!-- Here consistency checks concerning domain size and periodicity are necessary.
	1588	!-- Within this SELECT CASE structure only nzb_local is initialized individually depending on the
	1589	!-- chosen topography type, all other index arrays are initialized further below.
[1]	1590	SELECT CASE ( TRIM( topography ) )
	1591
	1592	CASE ( 'flat' )
[4648]	1593	!
[2232]	1594	!-- Initialilize 3D topography array, used later for initializing flags
[4340]	1595	topo(nzb+1:nzt+1,:,:) = IBSET( topo(nzb+1:nzt+1,:,:), 0 )
[4648]	1596
[4340]	1597	CASE ( 'closed_channel' )
[4648]	1598	!
[4340]	1599	!-- Initialilize 3D topography array, used later for initializing flags
[4648]	1600	topo(nzb+1:nzt,:,:) = IBSET( topo(nzb+1:nzt,:,:), 0 )
[1]	1601
	1602	CASE ( 'single_building' )
	1603	!
	1604	!-- Single rectangular building, by default centered in the middle of the
	1605	!-- total domain
[4386]	1606	ngp_bx = NINT( building_length_x / dx )
	1607	ngp_by = NINT( building_length_y / dy )
[2232]	1608	bh = MINLOC( ABS( zw - building_height ), 1 ) - 1
[4648]	1609	IF ( ABS( zw(bh) - building_height ) == ABS( zw(bh+1) - building_height ) ) bh = bh + 1
[1322]	1610	IF ( building_wall_left == 9999999.9_wp ) THEN
[4386]	1611	building_wall_left = ( nx + 1 - ngp_bx ) / 2 * dx
[1]	1612	ENDIF
[4386]	1613	index_left_bwall = NINT( building_wall_left / dx )
	1614	index_right_bwall = index_left_bwall + ngp_bx
[1]	1615
[1322]	1616	IF ( building_wall_south == 9999999.9_wp ) THEN
[4386]	1617	building_wall_south = ( ny + 1 - ngp_by ) / 2 * dy
[1]	1618	ENDIF
[4386]	1619	index_south_bwall = NINT( building_wall_south / dy )
	1620	index_north_bwall = index_south_bwall + ngp_by
[1]	1621
	1622	!
	1623	!-- Building size has to meet some requirements
[4648]	1624	IF ( ( index_left_bwall < 1 ) .OR. ( index_right_bwall > nx-1 ) .OR. &
	1625	( index_right_bwall < index_left_bwall+3 ) .OR. &
	1626	( index_south_bwall < 1 ) .OR. ( index_north_bwall > ny-1 ) .OR. &
[4386]	1627	( index_north_bwall < index_south_bwall+3 ) ) THEN
[4648]	1628	WRITE( message_string, * ) 'inconsistent building parameters:', &
	1629	'&index_left_bwall=', index_left_bwall, &
	1630	'index_right_bwall=', index_right_bwall, &
	1631	'index_south_bwall=', index_south_bwall, &
	1632	'index_north_bwall=', index_north_bwall, &
[4386]	1633	'nx=', nx, 'ny=', ny
[254]	1634	CALL message( 'init_grid', 'PA0203', 1, 2, 0, 6, 0 )
[1]	1635	ENDIF
	1636
[2696]	1637	ALLOCATE( nzb_local(nysg:nyng,nxlg:nxrg) )
[2892]	1638	nzb_local = 0
[1]	1639	!
[4648]	1640	!-- Define the building.
	1641	IF ( index_left_bwall <= nxr .AND. index_right_bwall >= nxl .AND. &
	1642	index_south_bwall <= nyn .AND. index_north_bwall >= nys ) &
	1643	nzb_local(MAX(nys,index_south_bwall):MIN(nyn,index_north_bwall), &
[4386]	1644	MAX(nxl,index_left_bwall):MIN(nxr,index_right_bwall)) = bh
[2232]	1645	!
[2696]	1646	!-- Set bit array on basis of nzb_local
	1647	DO i = nxl, nxr
	1648	DO j = nys, nyn
[4648]	1649	topo(nzb_local(j,i)+1:nzt+1,j,i) = IBSET( topo(nzb_local(j,i)+1:nzt+1,j,i), 0 )
[2232]	1650	ENDDO
	1651	ENDDO
[4648]	1652
[2696]	1653	DEALLOCATE( nzb_local )
[2232]	1654
[2696]	1655	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	1656	!
[4648]	1657	!-- Set boundary conditions also for flags. Can be interpreted as Neumannb oundary conditions
	1658	!-- for topography.
[2823]	1659	IF ( .NOT. bc_ns_cyc ) THEN
	1660	IF ( nys == 0 ) THEN
[4648]	1661	DO i = 1, nbgp
[2823]	1662	topo(:,nys-i,:) = topo(:,nys,:)
	1663	ENDDO
	1664	ENDIF
	1665	IF ( nyn == ny ) THEN
[4648]	1666	DO i = 1, nbgp
[2823]	1667	topo(:,nyn+i,:) = topo(:,nyn,:)
	1668	ENDDO
	1669	ENDIF
	1670	ENDIF
	1671	IF ( .NOT. bc_lr_cyc ) THEN
	1672	IF ( nxl == 0 ) THEN
[4648]	1673	DO i = 1, nbgp
[2823]	1674	topo(:,:,nxl-i) = topo(:,:,nxl)
	1675	ENDDO
	1676	ENDIF
[4648]	1677	IF ( nxr == nx ) THEN
	1678	DO i = 1, nbgp
	1679	topo(:,:,nxr+i) = topo(:,:,nxr)
[2823]	1680	ENDDO
[4648]	1681	ENDIF
[2823]	1682	ENDIF
[2232]	1683
[240]	1684	CASE ( 'single_street_canyon' )
	1685	!
	1686	!-- Single quasi-2D street canyon of infinite length in x or y direction.
	1687	!-- The canyon is centered in the other direction by default.
[1322]	1688	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[240]	1689	!
	1690	!-- Street canyon in y direction
[4386]	1691	ngp_cx = NINT( canyon_width_x / dx )
[1322]	1692	IF ( canyon_wall_left == 9999999.9_wp ) THEN
[4386]	1693	canyon_wall_left = ( nx + 1 - ngp_cx ) / 2 * dx
[240]	1694	ENDIF
[4386]	1695	index_left_cwall= NINT( canyon_wall_left / dx )
	1696	index_right_cwall= index_left_cwall+ ngp_cx
[1322]	1697	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[240]	1698	!
	1699	!-- Street canyon in x direction
[4386]	1700	ngp_cy = NINT( canyon_width_y / dy )
[1322]	1701	IF ( canyon_wall_south == 9999999.9_wp ) THEN
[4386]	1702	canyon_wall_south = ( ny + 1 - ngp_cy ) / 2 * dy
[240]	1703	ENDIF
[4386]	1704	index_south_cwall = NINT( canyon_wall_south / dy )
	1705	index_north_cwall = index_south_cwall + ngp_cy
[4648]	1706
[240]	1707	ELSE
[4648]	1708
[254]	1709	message_string = 'no street canyon width given'
	1710	CALL message( 'init_grid', 'PA0204', 1, 2, 0, 6, 0 )
[4648]	1711
[240]	1712	ENDIF
	1713
[2232]	1714	ch = MINLOC( ABS( zw - canyon_height ), 1 ) - 1
[4648]	1715	IF ( ABS( zw(ch) - canyon_height ) == ABS( zw(ch+1) - canyon_height ) ) ch = ch + 1
[240]	1716	dp_level_ind_b = ch
	1717	!
	1718	!-- Street canyon size has to meet some requirements
[1322]	1719	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[4648]	1720	IF ( ( index_left_cwall< 1 ) .OR. ( index_right_cwall> nx-1 ) .OR. &
[4543]	1721	( ngp_cx < 3 ) ) THEN
[4648]	1722	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
	1723	'&index_left_cwall=', index_left_cwall, &
	1724	' index_right_cwall=', index_right_cwall, &
	1725	' ngp_cx=', ngp_cx, ' ch=', ch, ' nx=', nx, ' ny=', ny
	1726	CALL message( 'init_grid', 'PA0205', 1, 2, 0, 6, 0 )
[240]	1727	ENDIF
[1322]	1728	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[4648]	1729	IF ( ( index_south_cwall < 1 ) .OR. &
	1730	( index_north_cwall > ny-1 ) .OR. ( ngp_cy < 3 ) ) THEN
	1731	WRITE( message_string, * ) 'inconsistent canyon parameters:', &
	1732	'&index_south_cwall=', index_south_cwall, &
	1733	' index_north_cwall=', index_north_cwall, &
	1734	' ngp_cy=', ngp_cy, ' ch=', ch, ' nx=', nx, ' ny=', ny
	1735	CALL message( 'init_grid', 'PA0206', 1, 2, 0, 6, 0 )
[240]	1736	ENDIF
	1737	ENDIF
[4648]	1738	IF ( canyon_width_x /= 9999999.9_wp .AND. canyon_width_y /= 9999999.9_wp ) THEN
	1739	message_string = 'inconsistent canyon parameters:' // &
	1740	'&street canyon can only be oriented' // &
[3045]	1741	' either in x- or in y-direction'
[254]	1742	CALL message( 'init_grid', 'PA0207', 1, 2, 0, 6, 0 )
[240]	1743	ENDIF
	1744
[2696]	1745	ALLOCATE( nzb_local(nysg:nyng,nxlg:nxrg) )
[240]	1746	nzb_local = ch
[1322]	1747	IF ( canyon_width_x /= 9999999.9_wp ) THEN
[4648]	1748	IF ( index_left_cwall<= nxr .AND. index_right_cwall>= nxl ) &
[4386]	1749	nzb_local(:,MAX(nxl,index_left_cwall+1):MIN(nxr,index_right_cwall-1)) = 0
[1322]	1750	ELSEIF ( canyon_width_y /= 9999999.9_wp ) THEN
[4648]	1751	IF ( index_south_cwall <= nyn .AND. index_north_cwall >= nys ) &
[4386]	1752	nzb_local(MAX(nys,index_south_cwall+1):MIN(nyn,index_north_cwall-1),:) = 0
[240]	1753	ENDIF
[2232]	1754	!
[2696]	1755	!-- Set bit array on basis of nzb_local
	1756	DO i = nxl, nxr
	1757	DO j = nys, nyn
[4648]	1758	topo(nzb_local(j,i)+1:nzt+1,j,i) = IBSET( topo(nzb_local(j,i)+1:nzt+1,j,i), 0 )
[2232]	1759	ENDDO
	1760	ENDDO
[2696]	1761	DEALLOCATE( nzb_local )
[1994]	1762
[2696]	1763	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	1764	!
[4648]	1765	!-- Set boundary conditions also for flags. Can be interpreted as Neumann boundary conditions
	1766	!-- for topography.
[2823]	1767	IF ( .NOT. bc_ns_cyc ) THEN
	1768	IF ( nys == 0 ) THEN
[4648]	1769	DO i = 1, nbgp
	1770	topo(:,nys-i,:) = topo(:,nys,:)
[2823]	1771	ENDDO
	1772	ENDIF
	1773	IF ( nyn == ny ) THEN
[4648]	1774	DO i = 1, nbgp
[2823]	1775	topo(:,nyn+i,:) = topo(:,nyn,:)
	1776	ENDDO
	1777	ENDIF
	1778	ENDIF
	1779	IF ( .NOT. bc_lr_cyc ) THEN
	1780	IF ( nxl == 0 ) THEN
[4648]	1781	DO i = 1, nbgp
	1782	topo(:,:,nxl-i) = topo(:,:,nxl)
[2823]	1783	ENDDO
	1784	ENDIF
[4648]	1785	IF ( nxr == nx ) THEN
	1786	DO i = 1, nbgp
	1787	topo(:,:,nxr+i) = topo(:,:,nxr)
[2823]	1788	ENDDO
[4648]	1789	ENDIF
[2823]	1790	ENDIF
[2232]	1791
	1792	CASE ( 'tunnel' )
	1793	!
	1794	!-- Tunnel height
	1795	IF ( tunnel_height == 9999999.9_wp ) THEN
	1796	th = zw( INT( 0.2 * nz) )
	1797	ELSE
	1798	th = tunnel_height
	1799	ENDIF
	1800	!
	1801	!-- Tunnel-wall depth
[4648]	1802	IF ( tunnel_wall_depth == 9999999.9_wp ) THEN
[3065]	1803	td = MAX ( dx, dy, dz(1) )
[2232]	1804	ELSE
	1805	td = tunnel_wall_depth
	1806	ENDIF
	1807	!
	1808	!-- Check for tunnel width
[4648]	1809	IF ( tunnel_width_x == 9999999.9_wp .AND. tunnel_width_y == 9999999.9_wp ) THEN
[2232]	1810	message_string = 'No tunnel width is given. '
[2274]	1811	CALL message( 'init_grid', 'PA0280', 1, 2, 0, 6, 0 )
[2232]	1812	ENDIF
[4648]	1813	IF ( tunnel_width_x /= 9999999.9_wp .AND. tunnel_width_y /= 9999999.9_wp ) THEN
	1814	message_string = 'Inconsistent tunnel parameters:' // &
	1815	'tunnel can only be oriented' // &
[2232]	1816	'either in x- or in y-direction.'
[2274]	1817	CALL message( 'init_grid', 'PA0281', 1, 2, 0, 6, 0 )
[2232]	1818	ENDIF
	1819	!
[4356]	1820	!-- Check for too small tunnel width in x- and y-direction
[4648]	1821	IF ( tunnel_width_x /= 9999999.9_wp .AND. &
[4356]	1822	tunnel_width_x - 2.0_wp * td <= 2.0_wp * dx ) THEN
	1823	message_string = 'tunnel_width_x too small'
	1824	CALL message( 'init_grid', 'PA0175', 1, 2, 0, 6, 0 )
	1825	ENDIF
[4648]	1826	IF ( tunnel_width_y /= 9999999.9_wp .AND. &
[4356]	1827	tunnel_width_y - 2.0_wp * td <= 2.0_wp * dy ) THEN
	1828	message_string = 'tunnel_width_y too small'
	1829	CALL message( 'init_grid', 'PA0455', 1, 2, 0, 6, 0 )
	1830	ENDIF
	1831	!
[4648]	1832	!-- Check for too large tunnel width.
[4356]	1833	!-- Tunnel axis along y.
[2232]	1834	IF ( tunnel_width_x /= 9999999.9_wp ) THEN
	1835	IF ( tunnel_width_x > ( nx + 1 ) * dx ) THEN
[4356]	1836	message_string = 'tunnel_width_x too large'
[2274]	1837	CALL message( 'init_grid', 'PA0282', 1, 2, 0, 6, 0 )
[2232]	1838	ENDIF
	1839
	1840	txs_out = INT( ( nx + 1 ) * 0.5_wp * dx - tunnel_width_x * 0.5_wp )
	1841	txe_out = INT( ( nx + 1 ) * 0.5_wp * dx + tunnel_width_x * 0.5_wp )
[4648]	1842	txs_in = INT( ( nx + 1 ) * 0.5_wp * dx - ( tunnel_width_x * 0.5_wp - td ) )
	1843	txe_in = INT( ( nx + 1 ) * 0.5_wp * dx + ( tunnel_width_x * 0.5_wp - td ) )
[2232]	1844
	1845	tys_out = INT( ( ny + 1 ) * 0.5_wp * dy - tunnel_length * 0.5_wp )
	1846	tye_out = INT( ( ny + 1 ) * 0.5_wp * dy + tunnel_length * 0.5_wp )
	1847	tys_in = tys_out
	1848	tye_in = tye_out
	1849	ENDIF
	1850	!
[4356]	1851	!-- Tunnel axis along x.
[2232]	1852	IF ( tunnel_width_y /= 9999999.9_wp ) THEN
	1853	IF ( tunnel_width_y > ( ny + 1 ) * dy ) THEN
[4356]	1854	message_string = 'tunnel_width_y too large'
[2274]	1855	CALL message( 'init_grid', 'PA0456', 1, 2, 0, 6, 0 )
[2232]	1856	ENDIF
	1857
	1858	txs_out = INT( ( nx + 1 ) * 0.5_wp * dx - tunnel_length * 0.5_wp )
	1859	txe_out = INT( ( nx + 1 ) * 0.5_wp * dx + tunnel_length * 0.5_wp )
	1860	txs_in = txs_out
	1861	txe_in = txe_out
	1862
	1863	tys_out = INT( ( ny + 1 ) * 0.5_wp * dy - tunnel_width_y * 0.5_wp )
	1864	tye_out = INT( ( ny + 1 ) * 0.5_wp * dy + tunnel_width_y * 0.5_wp )
[4648]	1865	tys_in = INT( ( ny + 1 ) * 0.5_wp * dy - ( tunnel_width_y * 0.5_wp - td ) )
	1866	tye_in = INT( ( ny + 1 ) * 0.5_wp * dy + ( tunnel_width_y * 0.5_wp - td ) )
[2232]	1867	ENDIF
	1868
[2696]	1869	topo = 0
[2232]	1870	DO i = nxl, nxr
	1871	DO j = nys, nyn
	1872	!
	1873	!-- Use heaviside function to model outer tunnel surface
[4648]	1874	hv_out = th * 0.5_wp * ( ( SIGN( 1.0_wp, i * dx - txs_out ) + 1.0_wp ) &
	1875	- ( SIGN( 1.0_wp, i * dx - txe_out ) + 1.0_wp ) )
[2232]	1876
[4648]	1877	hv_out = hv_out * 0.5_wp * ( ( SIGN( 1.0_wp, j * dy - tys_out ) + 1.0_wp ) &
	1878	- ( SIGN( 1.0_wp, j * dy - tye_out ) + 1.0_wp ) )
	1879	!
[2232]	1880	!-- Use heaviside function to model inner tunnel surface
[4648]	1881	hv_in = ( th - td ) * 0.5_wp * ( ( SIGN( 1.0_wp, i * dx - txs_in ) + 1.0_wp ) &
	1882	- ( SIGN( 1.0_wp, i * dx - txe_in ) + 1.0_wp ) )
[2232]	1883
[4648]	1884	hv_in = hv_in * 0.5_wp * ( ( SIGN( 1.0_wp, j * dy - tys_in ) + 1.0_wp ) &
	1885	- ( SIGN( 1.0_wp, j * dy - tye_in ) + 1.0_wp ) )
[2232]	1886	!
	1887	!-- Set flags at x-y-positions without any tunnel surface
	1888	IF ( hv_out - hv_in == 0.0_wp ) THEN
[2696]	1889	topo(nzb+1:nzt+1,j,i) = IBSET( topo(nzb+1:nzt+1,j,i), 0 )
[2232]	1890	!
	1891	!-- Set flags at x-y-positions with tunnel surfaces
	1892	ELSE
	1893	DO k = nzb + 1, nzt + 1
	1894	!
	1895	!-- Inner tunnel
	1896	IF ( hv_out - hv_in == th ) THEN
	1897	IF ( zw(k) <= hv_out ) THEN
[2696]	1898	topo(k,j,i) = IBCLR( topo(k,j,i), 0 )
[2232]	1899	ELSE
[2696]	1900	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	1901	ENDIF
	1902	ENDIF
	1903	!
	1904	!-- Lateral tunnel walls
	1905	IF ( hv_out - hv_in == td ) THEN
[4648]	1906	IF ( zw(k) <= hv_in ) THEN
[2696]	1907	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[4648]	1908	ELSEIF ( zw(k) > hv_in .AND. zw(k) <= hv_out ) THEN
[2696]	1909	topo(k,j,i) = IBCLR( topo(k,j,i), 0 )
[4648]	1910	ELSEIF ( zw(k) > hv_out ) THEN
[2696]	1911	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	1912	ENDIF
	1913	ENDIF
	1914	ENDDO
	1915	ENDIF
	1916	ENDDO
	1917	ENDDO
	1918
[2696]	1919	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2823]	1920	!
[4648]	1921	!-- Set boundary conditions also for flags. Can be interpreted as Neumann boundary conditions
	1922	!-- for topography.
[2823]	1923	IF ( .NOT. bc_ns_cyc ) THEN
	1924	IF ( nys == 0 ) THEN
[4648]	1925	DO i = 1, nbgp
	1926	topo(:,nys-i,:) = topo(:,nys,:)
[2823]	1927	ENDDO
	1928	ENDIF
	1929	IF ( nyn == ny ) THEN
[4648]	1930	DO i = 1, nbgp
[2823]	1931	topo(:,nyn+i,:) = topo(:,nyn,:)
	1932	ENDDO
	1933	ENDIF
	1934	ENDIF
	1935	IF ( .NOT. bc_lr_cyc ) THEN
	1936	IF ( nxl == 0 ) THEN
[4648]	1937	DO i = 1, nbgp
	1938	topo(:,:,nxl-i) = topo(:,:,nxl)
[2823]	1939	ENDDO
	1940	ENDIF
[4648]	1941	IF ( nxr == nx ) THEN
	1942	DO i = 1, nbgp
	1943	topo(:,:,nxr+i) = topo(:,:,nxr)
[2823]	1944	ENDDO
[4648]	1945	ENDIF
[2823]	1946	ENDIF
[2232]	1947
[1]	1948	CASE ( 'read_from_file' )
	1949	!
[4648]	1950	!-- Note, topography information have been already read.
	1951	!-- If required, further process topography, i.e. reference buildings on top of orography and
	1952	!-- set temporary 3D topography array, which is used later to set grid flags. Calling of this
	1953	!-- rouinte is also required in case of ASCII input, even though no distinction between
	1954	!-- terrain- and building height is made in this case.
[2696]	1955	CALL process_topography( topo )
[1968]	1956	!
[2696]	1957	!-- Filter holes resolved by only one grid-point
	1958	CALL filter_topography( topo )
[1968]	1959	!
[4648]	1960	!-- Exchange ghost-points, as well as add cyclic or Neumann boundary conditions.
[2696]	1961	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	1962	!
[4314]	1963	!-- Set lateral boundary conditions for topography on all ghost layers
[1968]	1964	IF ( .NOT. bc_ns_cyc ) THEN
[2550]	1965	IF ( nys == 0 ) THEN
[4648]	1966	DO i = 1, nbgp
[2696]	1967	topo(:,nys-i,:) = topo(:,nys,:)
	1968	ENDDO
[2550]	1969	ENDIF
[2696]	1970	IF ( nyn == ny ) THEN
[4648]	1971	DO i = 1, nbgp
[2696]	1972	topo(:,nyn+i,:) = topo(:,nyn,:)
	1973	ENDDO
	1974	ENDIF
[1942]	1975	ENDIF
[1910]	1976
[1968]	1977	IF ( .NOT. bc_lr_cyc ) THEN
[2550]	1978	IF ( nxl == 0 ) THEN
[4648]	1979	DO i = 1, nbgp
[2696]	1980	topo(:,:,nxl-i) = topo(:,:,nxl)
[2232]	1981	ENDDO
[2696]	1982	ENDIF
	1983	IF ( nxr == nx ) THEN
[4648]	1984	DO i = 1, nbgp
[2696]	1985	topo(:,:,nxr+i) = topo(:,:,nxr)
	1986	ENDDO
	1987	ENDIF
[2232]	1988	ENDIF
	1989
[667]	1990
[1]	1991	CASE DEFAULT
[4648]	1992	!
	1993	!-- The DEFAULT case is reached either if the parameter topography contains a wrong character
	1994	!-- string or if the user has defined a special case in the user interface. There, the
	1995	!-- subroutine user_init_grid checks which of these two conditions applies.
[2696]	1996	CALL user_init_grid( topo )
	1997	CALL filter_topography( topo )
[1]	1998
	1999	END SELECT
	2000	!
[4648]	2001	!-- Consistency checks and index array initialization are only required for non-flat topography.
[1]	2002	IF ( TRIM( topography ) /= 'flat' ) THEN
	2003	!
[4648]	2004	!-- In case of non-flat topography, check whether the convention how to define the topography
	2005	!-- grid has been set correctly, or whether the default is applicable. If this is not possible,
	2006	!-- abort.
[2232]	2007	IF ( TRIM( topography_grid_convention ) == ' ' ) THEN
[4648]	2008	IF ( TRIM( topography ) /= 'closed_channel' .AND. &
	2009	TRIM( topography ) /= 'single_building' .AND. &
	2010	TRIM( topography ) /= 'single_street_canyon' .AND. &
	2011	TRIM( topography ) /= 'tunnel' .AND. &
[2232]	2012	TRIM( topography ) /= 'read_from_file') THEN
[4648]	2013	!-- The default value is not applicable here, because it is only valid for the four
	2014	!-- standard cases 'single_building', 'single_street_canyon', 'tunnel' and 'read_from_file'
[2232]	2015	!-- defined in init_grid.
[4648]	2016	WRITE( message_string, * ) 'The value for "topography_grid_convention" ', &
	2017	'is not set. Its default value is & only valid for ', &
	2018	'"topography" = ''single_building'', ''tunnel'' ', &
	2019	'''single_street_canyon'', ''closed_channel'' & or ', &
	2020	'''read_from_file''.', &
	2021	'& Choose ''cell_edge'' or ''cell_center''.'
[2232]	2022	CALL message( 'init_grid', 'PA0239', 1, 2, 0, 6, 0 )
	2023	ELSE
	2024	!-- The default value is applicable here.
	2025	!-- Set convention according to topography.
[4648]	2026	IF ( TRIM( topography ) == 'single_building' .OR. &
[2232]	2027	TRIM( topography ) == 'single_street_canyon' ) THEN
	2028	topography_grid_convention = 'cell_edge'
[4648]	2029	ELSEIF ( TRIM( topography ) == 'read_from_file' .OR. &
[2232]	2030	TRIM( topography ) == 'tunnel') THEN
	2031	topography_grid_convention = 'cell_center'
	2032	ENDIF
	2033	ENDIF
[4648]	2034	ELSEIF ( TRIM( topography_grid_convention ) /= 'cell_edge' .AND. &
[2232]	2035	TRIM( topography_grid_convention ) /= 'cell_center' ) THEN
[4648]	2036	WRITE( message_string, * ) 'The value for "topography_grid_convention" is ', &
	2037	'not recognized.& Choose ''cell_edge'' or ''cell_center''.'
[2232]	2038	CALL message( 'init_grid', 'PA0240', 1, 2, 0, 6, 0 )
	2039	ENDIF
[1]	2040
[2169]	2041
[217]	2042	IF ( topography_grid_convention == 'cell_edge' ) THEN
[4648]	2043	!
	2044	!-- The array nzb_local as defined using the 'cell_edge' convention
	2045	!-- describes the actual total size of topography which is defined at the
	2046	!-- cell edges where u=0 on the topography walls in x-direction and v=0
[217]	2047	!-- on the topography walls in y-direction. However, PALM uses individual
	2048	!-- arrays nzb_u\|v\|w\|s_inner\|outer that are based on nzb_s_inner.
[4648]	2049	!-- Therefore, the extent of topography in nzb_local is now reduced by
	2050	!-- 1dx at the E topography walls and by 1dy at the N topography walls
	2051	!-- to form the basis for nzb_s_inner.
[1968]	2052	!-- Note, the reverse memory access (i-j instead of j-i) is absolutely
	2053	!-- required at this point.
	2054	DO j = nys+1, nyn+1
	2055	DO i = nxl-1, nxr
[2232]	2056	DO k = nzb, nzt+1
[4648]	2057	IF ( BTEST( topo(k,j,i), 0 ) .OR. BTEST( topo(k,j,i+1), 0 ) ) &
[2696]	2058	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2059	ENDDO
	2060	ENDDO
[4648]	2061	ENDDO
[2696]	2062	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2063
	2064	DO i = nxl, nxr+1
	2065	DO j = nys-1, nyn
	2066	DO k = nzb, nzt+1
[4648]	2067	IF ( BTEST( topo(k,j,i), 0 ) .OR. BTEST( topo(k,j+1,i), 0 ) ) &
[2696]	2068	topo(k,j,i) = IBSET( topo(k,j,i), 0 )
[2232]	2069	ENDDO
	2070	ENDDO
[4648]	2071	ENDDO
[2696]	2072	CALL exchange_horiz_int( topo, nys, nyn, nxl, nxr, nzt, nbgp )
[4648]	2073
[217]	2074	ENDIF
[2696]	2075	ENDIF
[2232]	2076
[2696]	2077	END SUBROUTINE init_topo
[1]	2078
[4868]	2079
[2696]	2080	SUBROUTINE set_topo_flags(topo)
[1]	2081
[4648]	2082	USE control_parameters, &
	2083	ONLY: bc_lr_cyc, bc_ns_cyc, constant_flux_layer, scalar_advec, topography, &
	2084	use_surface_fluxes, use_top_fluxes
[1]	2085
[4648]	2086	USE exchange_horiz_mod, &
[4457]	2087	ONLY: exchange_horiz_int
	2088
[4648]	2089	USE indices, &
	2090	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nzb, nzt, topo_top_ind, &
	2091	wall_flags_static_0, wall_flags_total_0
[1]	2092
[2696]	2093	USE kinds
[1]	2094
[2696]	2095	IMPLICIT NONE
[1804]	2096
[2696]	2097	INTEGER(iwp) :: i !< index variable along x
[4168]	2098	INTEGER(iwp) :: ibit !< integer bit position of topgraphy masking array
[2696]	2099	INTEGER(iwp) :: j !< index variable along y
	2100	INTEGER(iwp) :: k !< index variable along z
[1]	2101
[4648]	2102	INTEGER(iwp), DIMENSION(nzb:nzt+1,nysg:nyng,nxlg:nxrg) :: topo !< input array for 3D topography and dummy array for setting
	2103	!< "outer"-flags
[2232]	2104
[4329]	2105	ALLOCATE( wall_flags_static_0(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	2106	wall_flags_static_0 = 0
[2232]	2107	!
[2696]	2108	!-- Set-up topography flags. First, set flags only for s, u, v and w-grid.
[4648]	2109	!-- Further special flags will be set in following loops.
[2232]	2110	DO i = nxl, nxr
	2111	DO j = nys, nyn
	2112	DO k = nzb, nzt+1
	2113	!
	2114	!-- scalar grid
[4648]	2115	IF ( BTEST( topo(k,j,i), 0 ) ) &
[4329]	2116	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 0 )
[2232]	2117	!
[2696]	2118	!-- u grid
[4648]	2119	IF ( BTEST( topo(k,j,i), 0 ) .AND. BTEST( topo(k,j,i-1), 0 ) ) &
[4329]	2120	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 1 )
[2696]	2121	!
[2232]	2122	!-- v grid
[4648]	2123	IF ( BTEST( topo(k,j,i), 0 ) .AND. BTEST( topo(k,j-1,i), 0 ) ) &
[4329]	2124	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 2 )
[2696]	2125
[2232]	2126	ENDDO
[1]	2127
[4868]	2128	DO k = nzb, nzt
[1]	2129	!
[2232]	2130	!-- w grid
[4648]	2131	IF ( BTEST( topo(k,j,i), 0 ) .AND. BTEST( topo(k+1,j,i), 0 ) ) &
[4329]	2132	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 3 )
[2232]	2133	ENDDO
[4648]	2134
	2135	IF ( topography /= 'closed_channel' ) THEN
[4340]	2136	wall_flags_static_0(nzt+1,j,i) = IBSET( wall_flags_static_0(nzt+1,j,i), 3 )
	2137	ENDIF
[2232]	2138
	2139	ENDDO
	2140	ENDDO
[2696]	2141
[4329]	2142	CALL exchange_horiz_int( wall_flags_static_0, nys, nyn, nxl, nxr, nzt, nbgp )
[4346]	2143
[1]	2144	!
[4648]	2145	!-- Set outer array for scalars to mask near-surface grid points. Note, on basis of flag 24 futher
	2146	!-- flags will be derived which are used to control production of subgrid TKE production near walls.
[4346]	2147	ALLOCATE( wall_flags_total_0(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	2148	wall_flags_total_0 = 0
[4648]	2149
[4868]	2150	DO i = nxl, nxr
	2151	DO j = nys, nyn
	2152	DO k = nzb, nzt+1
[4346]	2153	wall_flags_total_0(k,j,i) = IOR( wall_flags_total_0(k,j,i), wall_flags_static_0(k,j,i) )
[2232]	2154	ENDDO
	2155	ENDDO
	2156	ENDDO
[4648]	2157
[4346]	2158	CALL exchange_horiz_int( wall_flags_total_0, nys, nyn, nxl, nxr, nzt, nbgp )
[4648]	2159
[4868]	2160	DO i = nxl, nxr
	2161	DO j = nys, nyn
	2162	DO k = nzb, nzt+1
[4648]	2163	IF ( BTEST( wall_flags_total_0(k,j-1,i), 0 ) .AND. &
	2164	BTEST( wall_flags_total_0(k,j+1,i), 0 ) .AND. &
	2165	BTEST( wall_flags_total_0(k,j,i-1), 0 ) .AND. &
	2166	BTEST( wall_flags_total_0(k,j,i+1), 0 ) .AND. &
	2167	BTEST( wall_flags_total_0(k,j-1,i-1), 0 ) .AND. &
	2168	BTEST( wall_flags_total_0(k,j+1,i-1), 0 ) .AND. &
	2169	BTEST( wall_flags_total_0(k,j-1,i+1), 0 ) .AND. &
	2170	BTEST( wall_flags_total_0(k,j+1,i+1), 0 ) ) &
[4346]	2171	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 24 )
	2172	ENDDO
	2173	ENDDO
	2174	ENDDO
[1]	2175	!
[2232]	2176	!-- Set further special flags
[4868]	2177	DO i = nxl, nxr
	2178	DO j = nys, nyn
	2179	DO k = nzb, nzt+1
[1]	2180	!
[2232]	2181	!-- scalar grid, former nzb_diff_s_inner.
[4648]	2182	!-- Note, use this flag also to mask topography in diffusion_u and diffusion_v along the
	2183	!-- vertical direction. In case of use_surface_fluxes, fluxes are calculated via MOST,
	2184	!-- else, simple gradient approach is applied. Please note, in case of u- and v-diffuison,
	2185	!-- a small error is made at edges (on the east side for u, at the north side for v), since
	2186	!-- topography on scalar grid point is used instead of topography on u/v-grid. As number of
	2187	!-- topography grid points on uv-grid is different than s-grid, different number of surface
	2188	!-- elements would be required. In order to avoid this, treat edges (u(k,j,i+1)) simply by
	2189	!-- a gradient approach, i.e. these points are not masked within diffusion_u. Tests had
	2190	!-- shown that the effect on the flow is negligible.
[2232]	2191	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4648]	2192	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
[4346]	2193	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 8 )
[2232]	2194	ELSE
[4346]	2195	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 8 )
[2232]	2196	ENDIF
[1]	2197
[2232]	2198	ENDDO
	2199	!
[4648]	2200	!-- Special flag to control vertical diffusion at model top - former nzt_diff
[4346]	2201	wall_flags_total_0(:,j,i) = IBSET( wall_flags_total_0(:,j,i), 9 )
[2232]	2202	IF ( use_top_fluxes ) &
[4346]	2203	wall_flags_total_0(nzt+1,j,i) = IBCLR( wall_flags_total_0(nzt+1,j,i), 9 )
[1]	2204
[2696]	2205
[4868]	2206	DO k = nzb+1, nzt
[2232]	2207	!
[4648]	2208	!-- Special flag on u grid, former nzb_u_inner + 1, required for disturb_field and
	2209	!-- initialization. Do not disturb directly at topography, as well as initialize u with
	2210	!-- zero one grid point outside of topography.
	2211	IF ( BTEST( wall_flags_total_0(k-1,j,i), 1 ) .AND. &
	2212	BTEST( wall_flags_total_0(k,j,i), 1 ) .AND. &
	2213	BTEST( wall_flags_total_0(k+1,j,i), 1 ) ) &
[4346]	2214	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 20 )
[2232]	2215	!
[4648]	2216	!-- Special flag on v grid, former nzb_v_inner + 1, required for disturb_field and
	2217	!-- initialization. Do not disturb directly at topography, as well as initialize v with
	2218	!-- zero one grid point outside of topography.
	2219	IF ( BTEST( wall_flags_total_0(k-1,j,i), 2 ) .AND. &
	2220	BTEST( wall_flags_total_0(k,j,i), 2 ) .AND. &
	2221	BTEST( wall_flags_total_0(k+1,j,i), 2 ) ) &
[4346]	2222	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 21 )
[2232]	2223	!
[4648]	2224	!-- Special flag on scalar grid, former nzb_s_inner+1. Used for lpm_sgs_tke
	2225	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2226	BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2227	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
[4346]	2228	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 25 )
[2232]	2229	!
[4648]	2230	!-- Special flag on scalar grid, nzb_diff_s_outer - 1, required in in production_e
[2232]	2231	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4648]	2232	IF ( BTEST( wall_flags_total_0(k,j,i), 24 ) .AND. &
	2233	BTEST( wall_flags_total_0(k-1,j,i), 24 ) .AND. &
	2234	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
[4346]	2235	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 29 )
[2232]	2236	ELSE
[4648]	2237	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
[4346]	2238	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 29 )
[1]	2239	ENDIF
[2232]	2240	!
[4648]	2241	!-- Special flag on scalar grid, nzb_diff_s_outer - 1, required in
[2232]	2242	!-- in production_e
	2243	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4648]	2244	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2245	BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2246	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
[4346]	2247	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 30 )
[2232]	2248	ELSE
[4648]	2249	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
[4346]	2250	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 30 )
[2232]	2251	ENDIF
	2252	ENDDO
	2253	!
	2254	!-- Flags indicating downward facing walls
[4868]	2255	DO k = nzb+1, nzt+1
[2232]	2256	!
	2257	!-- Scalar grid
[4648]	2258	IF ( BTEST( wall_flags_total_0(k-1,j,i), 0 ) .AND. &
	2259	.NOT. BTEST( wall_flags_total_0(k,j,i), 0 ) ) &
	2260	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 13 )
[2232]	2261	!
	2262	!-- Downward facing wall on u grid
[4648]	2263	IF ( BTEST( wall_flags_total_0(k-1,j,i), 1 ) .AND. &
	2264	.NOT. BTEST( wall_flags_total_0(k,j,i), 1 ) ) &
[4346]	2265	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 15 )
[2232]	2266	!
	2267	!-- Downward facing wall on v grid
[4648]	2268	IF ( BTEST( wall_flags_total_0(k-1,j,i), 2 ) .AND. &
	2269	.NOT. BTEST( wall_flags_total_0(k,j,i), 2 ) ) &
[4346]	2270	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 17 )
[2232]	2271	!
	2272	!-- Downward facing wall on w grid
[4648]	2273	IF ( BTEST( wall_flags_total_0(k-1,j,i), 3 ) .AND. &
	2274	.NOT. BTEST( wall_flags_total_0(k,j,i), 3 ) ) &
[4346]	2275	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 19 )
[2232]	2276	ENDDO
	2277	!
	2278	!-- Flags indicating upward facing walls
[4868]	2279	DO k = nzb, nzt
[2232]	2280	!
	2281	!-- Upward facing wall on scalar grid
[4648]	2282	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2283	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
[4346]	2284	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 12 )
[2232]	2285	!
	2286	!-- Upward facing wall on u grid
[4648]	2287	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 1 ) .AND. &
	2288	BTEST( wall_flags_total_0(k+1,j,i), 1 ) ) &
[4346]	2289	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 14 )
[1]	2290
[4648]	2291	!
[2232]	2292	!-- Upward facing wall on v grid
[4648]	2293	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 2 ) .AND. &
	2294	BTEST( wall_flags_total_0(k+1,j,i), 2 ) ) &
[4346]	2295	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 16 )
[4648]	2296
[2232]	2297	!
	2298	!-- Upward facing wall on w grid
[4648]	2299	IF ( .NOT. BTEST( wall_flags_total_0(k,j,i), 3 ) .AND. &
	2300	BTEST( wall_flags_total_0(k+1,j,i), 3 ) ) &
[4346]	2301	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 18 )
[2232]	2302	!
	2303	!-- Special flag on scalar grid, former nzb_s_inner
[4648]	2304	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .OR. &
	2305	BTEST( wall_flags_total_0(k,j,i), 12 ) .OR. &
	2306	BTEST( wall_flags_total_0(k,j,i), 13 ) ) &
[4346]	2307	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 22 )
[2232]	2308	!
[4648]	2309	!-- Special flag on scalar grid, nzb_diff_s_inner - 1, required for
[2232]	2310	!-- flow_statistics
	2311	IF ( constant_flux_layer .OR. use_surface_fluxes ) THEN
[4648]	2312	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. &
	2313	BTEST( wall_flags_total_0(k+1,j,i), 0 ) ) &
[4346]	2314	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 23 )
[2232]	2315	ELSE
[4648]	2316	IF ( BTEST( wall_flags_total_0(k,j,i), 22 ) ) &
[4346]	2317	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 23 )
[1]	2318	ENDIF
	2319
[4648]	2320
[2232]	2321	ENDDO
[4346]	2322	wall_flags_total_0(nzt+1,j,i) = IBSET( wall_flags_total_0(nzt+1,j,i), 22 )
	2323	wall_flags_total_0(nzt+1,j,i) = IBSET( wall_flags_total_0(nzt+1,j,i), 23 )
[4109]	2324	!
[4648]	2325	!-- Set flags indicating that topography is close by in horizontal direction, i.e. flags that
	2326	!-- infold the topography. These will be used to set advection flags for passive scalars,
	2327	!-- where due to large gradients near buildings stationary numerical oscillations can produce
	2328	!-- unrealistically high concentrations. This is only necessary if WS-scheme is applied for
	2329	!-- scalar advection. Note, these flags will be only used for passive scalars such as chemical
	2330	!-- species or aerosols.
[4109]	2331	IF ( scalar_advec == 'ws-scheme' ) THEN
[4868]	2332	DO k = nzb, nzt
[4648]	2333	IF ( BTEST( wall_flags_total_0(k,j,i), 0 ) .AND. ( &
	2334	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-1), 0 ) ) .OR. &
	2335	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-2), 0 ) ) .OR. &
	2336	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i-3), 0 ) ) .OR. &
	2337	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+1), 0 ) ) .OR. &
	2338	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+2), 0 ) ) .OR. &
	2339	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3:j+3,i+3), 0 ) ) .OR. &
	2340	ANY( .NOT. BTEST( wall_flags_total_0(k,j-1,i-3:i+3), 0 ) ) .OR. &
	2341	ANY( .NOT. BTEST( wall_flags_total_0(k,j-2,i-3:i+3), 0 ) ) .OR. &
	2342	ANY( .NOT. BTEST( wall_flags_total_0(k,j-3,i-3:i+3), 0 ) ) .OR. &
	2343	ANY( .NOT. BTEST( wall_flags_total_0(k,j+1,i-3:i+3), 0 ) ) .OR. &
	2344	ANY( .NOT. BTEST( wall_flags_total_0(k,j+2,i-3:i+3), 0 ) ) .OR. &
	2345	ANY( .NOT. BTEST( wall_flags_total_0(k,j+3,i-3:i+3), 0 ) ) &
	2346	) &
	2347	) &
[4346]	2348	wall_flags_total_0(k,j,i) = IBSET( wall_flags_total_0(k,j,i), 31 )
[4109]	2349	ENDDO
	2350	ENDIF
[2232]	2351	ENDDO
	2352	ENDDO
	2353	!
[2696]	2354	!-- Finally, set identification flags indicating natural terrain or buildings.
[4648]	2355	!-- Natural terrain grid points. Information on the type of the surface is stored in bit 1 of
	2356	!-- 3D Integer array topo. However, this bit is only set when topography is read from file. In order
	2357	!-- to run the land-surface model also without topography information, set bit 1 explicitely in this
	2358	!-- case.
	2359	!--
[4294]	2360	!-- Natural terrain grid points
	2361	!-- If no topography is initialized, the land-surface is at k = nzb.
	2362	IF ( TRIM( topography ) /= 'read_from_file' ) THEN
[4329]	2363	wall_flags_static_0(nzb,:,:) = IBSET( wall_flags_static_0(nzb,:,:), 5 )
[4294]	2364	ELSE
[4868]	2365	DO i = nxl, nxr
	2366	DO j = nys, nyn
	2367	DO k = nzb, nzt+1
[4648]	2368	!
[4294]	2369	!-- Natural terrain grid point
[4648]	2370	IF ( BTEST( topo(k,j,i), 1 ) ) &
[4329]	2371	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 5 )
[2696]	2372	ENDDO
	2373	ENDDO
[4294]	2374	ENDDO
[2696]	2375	ENDIF
	2376	!
	2377	!-- Building grid points.
[4868]	2378	DO i = nxl, nxr
	2379	DO j = nys, nyn
	2380	DO k = nzb, nzt+1
[4648]	2381	IF ( BTEST( topo(k,j,i), 2 ) ) &
[4329]	2382	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 6 )
[2696]	2383	ENDDO
	2384	ENDDO
[4294]	2385	ENDDO
[2696]	2386	!
[4314]	2387	!-- Set flag 4, indicating new topography grid points due to filtering.
[4868]	2388	DO i = nxl, nxr
	2389	DO j = nys, nyn
	2390	DO k = nzb, nzt+1
[4648]	2391	IF ( BTEST( topo(k,j,i), 4 ) ) &
[4329]	2392	wall_flags_static_0(k,j,i) = IBSET( wall_flags_static_0(k,j,i), 4 )
[4314]	2393	ENDDO
	2394	ENDDO
	2395	ENDDO
[4648]	2396
[4346]	2397	CALL exchange_horiz_int( wall_flags_static_0, nys, nyn, nxl, nxr, nzt, nbgp )
[4648]	2398
[4868]	2399	DO i = nxl, nxr
	2400	DO j = nys, nyn
	2401	DO k = nzb, nzt+1
[4346]	2402	wall_flags_total_0(k,j,i) = IOR( wall_flags_total_0(k,j,i), wall_flags_static_0(k,j,i) )
	2403	ENDDO
	2404	ENDDO
	2405	ENDDO
[4314]	2406	!
[2232]	2407	!-- Exchange ghost points for wall flags
[4346]	2408	CALL exchange_horiz_int( wall_flags_total_0, nys, nyn, nxl, nxr, nzt, nbgp )
[2232]	2409	!
[4648]	2410	!-- Set boundary conditions also for flags. Can be interpreted as Neumann boundary conditions for
	2411	!-- topography.
[2232]	2412	IF ( .NOT. bc_ns_cyc ) THEN
[2696]	2413	IF ( nys == 0 ) THEN
[4648]	2414	DO i = 1, nbgp
[4346]	2415	wall_flags_total_0(:,nys-i,:) = wall_flags_total_0(:,nys,:)
[2696]	2416	ENDDO
	2417	ENDIF
	2418	IF ( nyn == ny ) THEN
[4648]	2419	DO i = 1, nbgp
[4346]	2420	wall_flags_total_0(:,nyn+i,:) = wall_flags_total_0(:,nyn,:)
[2696]	2421	ENDDO
	2422	ENDIF
[2232]	2423	ENDIF
	2424	IF ( .NOT. bc_lr_cyc ) THEN
[2696]	2425	IF ( nxl == 0 ) THEN
[4648]	2426	DO i = 1, nbgp
[4346]	2427	wall_flags_total_0(:,:,nxl-i) = wall_flags_total_0(:,:,nxl)
[2696]	2428	ENDDO
[2232]	2429	ENDIF
[4648]	2430	IF ( nxr == nx ) THEN
	2431	DO i = 1, nbgp
	2432	wall_flags_total_0(:,:,nxr+i) = wall_flags_total_0(:,:,nxr)
[2232]	2433	ENDDO
[4648]	2434	ENDIF
[2232]	2435	ENDIF
[4168]	2436	!
[4648]	2437	!-- Pre-calculate topography top indices (former get_topography_top_index
[4168]	2438	!-- function)
[4653]	2439	ALLOCATE( topo_top_ind(nysg:nyng,nxlg:nxrg,0:5) )
[4168]	2440	!
	2441	!-- Uppermost topography index on scalar grid
	2442	ibit = 12
[4648]	2443	topo_top_ind(:,:,0) = MAXLOC( MERGE( 1, 0, BTEST( wall_flags_total_0(:,:,:), ibit ) ), DIM=1 ) &
	2444	- 1
[4168]	2445	!
[4648]	2446	!-- Uppermost topography index on u grid
[4168]	2447	ibit = 14
[4648]	2448	topo_top_ind(:,:,1) = MAXLOC( MERGE( 1, 0, BTEST( wall_flags_total_0(:,:,:), ibit ) ), DIM=1 ) &
	2449	- 1
[4168]	2450	!
[4648]	2451	!-- Uppermost topography index on v grid
[4168]	2452	ibit = 16
[4648]	2453	topo_top_ind(:,:,2) = MAXLOC( MERGE( 1, 0, BTEST( wall_flags_total_0(:,:,:), ibit ) ), DIM=1 ) &
	2454	- 1
[4168]	2455	!
	2456	!-- Uppermost topography index on w grid
	2457	ibit = 18
[4648]	2458	topo_top_ind(:,:,3) = MAXLOC( MERGE( 1, 0, BTEST( wall_flags_total_0(:,:,:), ibit ) ), DIM=1 ) &
	2459	- 1
[4168]	2460	!
	2461	!-- Uppermost topography index on scalar outer grid
	2462	ibit = 24
[4648]	2463	topo_top_ind(:,:,4) = MAXLOC( MERGE( 1, 0, BTEST( wall_flags_total_0(:,:,:), ibit ) ), DIM=1 ) &
	2464	- 1
[4653]	2465	!
	2466	!-- Uppermost topography index including full-3D geometry
	2467	ibit = 12
	2468	DO k = nzb, nzt+1
	2469	WHERE( BTEST( wall_flags_total_0(k,:,:), ibit ) ) topo_top_ind(:,:,5) = k
	2470	ENDDO
[4414]	2471
[2696]	2472	END SUBROUTINE set_topo_flags

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source: palm/trunk/SOURCE/init_grid.f90 @ 4878

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