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source: palm/trunk/SOURCE/synthetic_turbulence_generator_mod.f90 @ 4372

Last change on this file since 4372 was 4346, checked in by motisi, 5 years ago
Introduction of wall_flags_total_0, which currently sets bits based on static topography information used in wall_flags_static_0
Property svn:keywords set to `Id`
File size: 106.0 KB

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[2259]	1	!> @synthetic_turbulence_generator_mod.f90
	2	!------------------------------------------------------------------------------!
[2696]	3	! This file is part of the PALM model system.
[2259]	4	!
[2696]	5	! PALM is free software: you can redistribute it and/or modify it under the
[2259]	6	! terms of the GNU General Public License as published by the Free Software
	7	! Foundation, either version 3 of the License, or (at your option) any later
	8	! version.
	9	!
[2696]	10	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
[2259]	11	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
	12	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
	13	!
	14	! You should have received a copy of the GNU General Public License along with
	15	! PALM. If not, see <http://www.gnu.org/licenses/>.
	16	!
[3885]	17	! Copyright 2017-2019 Leibniz Universitaet Hannover
[2259]	18	!------------------------------------------------------------------------------!
	19	!
	20	! Current revisions:
	21	! -----------------
	22	!
[3349]	23	!
[2259]	24	! Former revisions:
	25	! -----------------
	26	! $Id: synthetic_turbulence_generator_mod.f90 4346 2019-12-18 11:55:56Z banzhafs $
[4346]	27	! Introduction of wall_flags_total_0, which currently sets bits based on static
	28	! topography information used in wall_flags_static_0
	29	!
	30	! 4335 2019-12-12 16:39:05Z suehring
[4335]	31	! Commentation of last commit
	32	!
	33	! 4332 2019-12-10 19:44:12Z suehring
[4332]	34	! Limit initial velocity seeds in restart runs, if not the seed calculation
	35	! may become unstable. Further, minor bugfix in initial velocity seed
	36	! calculation.
	37	!
	38	! 4329 2019-12-10 15:46:36Z motisi
[4329]	39	! Renamed wall_flags_0 to wall_flags_static_0
	40	!
	41	! 4309 2019-11-26 18:49:59Z suehring
[4309]	42	! Computation of velocity seeds optimized. This implies that random numbers
	43	! are computed now using the parallel random number generator. Random numbers
	44	! are now only computed and normalized locally, while distributed over all
	45	! mpi ranks afterwards, instead of computing random numbers on a global array.
	46	! Further, the number of calls for the time-consuming velocity-seed generation
	47	! is reduced - now the left and right, as well as the north and south boundary
	48	! share the same velocity-seed matrices.
	49	!
	50	! 4182 2019-08-22 15:20:23Z scharf
[4182]	51	! Corrected "Former revisions" section
	52	!
	53	! 4148 2019-08-08 11:26:00Z suehring
[4148]	54	! Remove unused variable
	55	!
	56	! 4144 2019-08-06 09:11:47Z raasch
[4144]	57	! relational operators .EQ., .NE., etc. replaced by ==, /=, etc.
	58	!
	59	! 4071 2019-07-03 20:02:00Z suehring
[4071]	60	! Bugfix, initialize mean_inflow_profiles in case turbulence and inflow
	61	! information is not read from file.
	62	!
	63	! 4022 2019-06-12 11:52:39Z suehring
[4022]	64	! Several bugfixes and improvements
	65	! - revise bias correction of the imposed perturbations (correction via volume
	66	! flow can create instabilities in case the mean volume flow is close to zero)
	67	! - introduce lower limits in calculation of coefficient matrix, else the
	68	! calculation may become numerically unstable
	69	! - impose perturbations every timestep, even though no new set of perturbations
	70	! is generated in case dt_stg_call /= dt_3d
	71	! - Implement a gradual decrease of Reynolds stress and length scales above
	72	! ABL height (within 1 length scale above ABL depth to 1/10) rather than a
	73	! discontinuous decrease
	74	! - Bugfix in non-nested case: use ABL height for parametrized turbulence
	75	!
	76	! 3987 2019-05-22 09:52:13Z kanani
[3987]	77	! Introduce alternative switch for debug output during timestepping
	78	!
	79	! 3938 2019-04-29 16:06:25Z suehring
[3938]	80	! Remove unused variables
	81	!
	82	! 3937 2019-04-29 15:09:07Z suehring
[3937]	83	! Minor bugfix in case of a very early restart where mc_factor is sill not
	84	! present.
	85	! Some modification and fixing of potential bugs in the calculation of scaling
	86	! parameters used for synthetic turbulence parametrization.
	87	!
	88	! 3909 2019-04-17 09:13:25Z suehring
[3909]	89	! Minor bugfix for last commit
	90	!
	91	! 3900 2019-04-16 15:17:43Z suehring
[3900]	92	! Missing re-calculation of perturbation seeds in case of restarts
	93	!
	94	! 3891 2019-04-12 17:52:01Z suehring
[3891]	95	! Bugfix in initialization in case of restart runs.
	96	!
	97	! 3885 2019-04-11 11:29:34Z kanani
[3885]	98	! Changes related to global restructuring of location messages and introduction
	99	! of additional debug messages
	100	!
	101	!
[3775]	102	! removed unused variables
	103	!
	104	! 3719 2019-02-06 13:10:18Z kanani
[3719]	105	! Removed log_point measurement from stg_init, since this part is counted to
	106	! log_point(2) 'initialisation' already. Moved other log_points to calls of
	107	! the subroutines in time_integration for better overview.
	108	!
[4182]	109	! 2259 2017-06-08 09:09:11Z gronemeier
	110	! Initial revision
[3044]	111	!
[4182]	112	! Authors:
	113	! --------
	114	! @author Tobias Gronemeier, Matthias Suehring, Atsushi Inagaki, Micha Gryschka, Christoph Knigge
	115	!
	116	!
[2259]	117	! Description:
	118	! ------------
	119	!> The module generates turbulence at the inflow boundary based on a method by
	120	!> Xie and Castro (2008) utilizing a Lund rotation (Lund, 1998) and a mass-flux
	121	!> correction by Kim et al. (2013).
	122	!> The turbulence is correlated based on length scales in y- and z-direction and
	123	!> a time scale for each velocity component. The profiles of length and time
	124	!> scales, mean u, v, w, e and pt, and all components of the Reynolds stress
[3347]	125	!> tensor can be either read from file STG_PROFILES, or will be parametrized
	126	!> within the boundary layer.
[2259]	127	!>
	128	!> @todo test restart
	129	!> enable cyclic_fill
	130	!> implement turbulence generation for e and pt
[2945]	131	!> @todo Input of height-constant length scales via namelist
[2259]	132	!> @note <Enter notes on the module>
	133	!> @bug Height information from input file is not used. Profiles from input
	134	!> must match with current PALM grid.
	135	!> In case of restart, velocity seeds differ from precursor run if a11,
	136	!> a22, or a33 are zero.
	137	!------------------------------------------------------------------------------!
	138	MODULE synthetic_turbulence_generator_mod
	139
	140
	141	USE arrays_3d, &
[4022]	142	ONLY: dzw, &
	143	ddzw, &
	144	drho_air, &
	145	mean_inflow_profiles, &
	146	q, &
[4071]	147	q_init, &
	148	pt, &
	149	pt_init, &
[4022]	150	u, &
	151	u_init, &
	152	v, &
	153	v_init, &
	154	w, &
	155	zu, &
	156	zw
[2259]	157
[3274]	158	USE basic_constants_and_equations_mod, &
[4022]	159	ONLY: g, &
	160	kappa, &
	161	pi
[2259]	162
	163	USE control_parameters, &
[4022]	164	ONLY: bc_lr, &
	165	bc_ns, &
	166	child_domain, &
	167	coupling_char, &
	168	debug_output_timestep, &
	169	dt_3d, &
	170	e_init, &
[4071]	171	humidity, &
[3885]	172	initializing_actions, &
[4022]	173	intermediate_timestep_count, &
	174	intermediate_timestep_count_max, &
	175	length, &
[3885]	176	message_string, &
[4022]	177	nesting_offline, &
[4071]	178	neutral, &
[3885]	179	num_mean_inflow_profiles, &
[4309]	180	random_generator, &
[4022]	181	rans_mode, &
	182	restart_string, &
	183	syn_turb_gen, &
	184	time_since_reference_point, &
	185	turbulent_inflow
	186
	187	USE grid_variables, &
	188	ONLY: ddx, &
	189	ddy, &
	190	dx, &
	191	dy
[2259]	192
	193	USE indices, &
[4022]	194	ONLY: nbgp, &
	195	nz, &
	196	nzb, &
	197	nzt, &
	198	nx, &
	199	nxl, &
	200	nxlu, &
	201	nxlg, &
	202	nxr, &
	203	nxrg, &
	204	ny, &
	205	nys, &
	206	nysv, &
	207	nyn, &
	208	nyng, &
	209	nysg, &
[4346]	210	wall_flags_total_0
[2259]	211
	212	USE kinds
	213
[2967]	214	#if defined( __parallel ) && !defined( __mpifh )
[2259]	215	USE MPI
[2841]	216	#endif
[2259]	217
[3347]	218	USE nesting_offl_mod, &
[4022]	219	ONLY: nesting_offl_calc_zi, &
	220	zi_ribulk
[3347]	221
[2259]	222	USE pegrid, &
[4022]	223	ONLY: comm1dx, &
	224	comm1dy, &
	225	comm2d, &
	226	ierr, &
	227	myidx, &
	228	myidy, &
	229	pdims
	230
	231	USE pmc_interface, &
	232	ONLY : rans_mode_parent
[4309]	233
	234	USE random_generator_parallel, &
	235	ONLY: random_dummy, &
	236	random_number_parallel, &
	237	random_seed_parallel, &
	238	seq_random_array
[2259]	239
	240	USE transpose_indices, &
[4022]	241	ONLY: nzb_x, &
	242	nzt_x
[2259]	243
	244
	245	IMPLICIT NONE
	246
[2967]	247	#if defined( __parallel ) && defined( __mpifh )
[2841]	248	INCLUDE "mpif.h"
	249	#endif
	250
[3182]	251
[3347]	252	LOGICAL :: velocity_seed_initialized = .FALSE. !< true after first call of stg_main
	253	LOGICAL :: parametrize_inflow_turbulence = .FALSE. !< flag indicating that inflow turbulence is either read from file (.FALSE.) or if it parametrized
	254	LOGICAL :: use_syn_turb_gen = .FALSE. !< switch to use synthetic turbulence generator
[2259]	255
[3038]	256	INTEGER(iwp) :: id_stg_left !< left lateral boundary core id in case of turbulence generator
	257	INTEGER(iwp) :: id_stg_north !< north lateral boundary core id in case of turbulence generator
	258	INTEGER(iwp) :: id_stg_right !< right lateral boundary core id in case of turbulence generator
	259	INTEGER(iwp) :: id_stg_south !< south lateral boundary core id in case of turbulence generator
[2938]	260	INTEGER(iwp) :: merg !< maximum length scale (in gp)
	261	INTEGER(iwp) :: mergp !< merg + nbgp
[3038]	262	INTEGER(iwp) :: nzb_x_stg !< lower bound of z coordinate (required for transposing z on PEs along x)
	263	INTEGER(iwp) :: nzt_x_stg !< upper bound of z coordinate (required for transposing z on PEs along x)
	264	INTEGER(iwp) :: nzb_y_stg !< lower bound of z coordinate (required for transposing z on PEs along y)
	265	INTEGER(iwp) :: nzt_y_stg !< upper bound of z coordinate (required for transposing z on PEs along y)
[4309]	266	INTEGER(iwp) :: stg_type_xz !< MPI type for full z range
	267	INTEGER(iwp) :: stg_type_xz_small !< MPI type for small z range
	268	INTEGER(iwp) :: stg_type_yz !< MPI type for full z range
	269	INTEGER(iwp) :: stg_type_yz_small !< MPI type for small z range
[2259]	270
[4022]	271	INTEGER(iwp), DIMENSION(3) :: nr_non_topo_xz = 0 !< number of non-topography grid points at xz cross-sections,
	272	!< required for bias correction of imposed perturbations
	273	INTEGER(iwp), DIMENSION(3) :: nr_non_topo_yz = 0 !< number of non-topography grid points at yz cross-sections,
	274	!< required for bias correction of imposed perturbations
	275
[3347]	276	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: displs_xz !< displacement for MPI_GATHERV
	277	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: recv_count_xz !< receive count for MPI_GATHERV
	278	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: displs_yz !< displacement for MPI_GATHERV
	279	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: recv_count_yz !< receive count for MPI_GATHERV
	280	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nux !< length scale of u in x direction (in gp)
	281	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nuy !< length scale of u in y direction (in gp)
	282	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nuz !< length scale of u in z direction (in gp)
	283	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nvx !< length scale of v in x direction (in gp)
	284	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nvy !< length scale of v in y direction (in gp)
	285	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nvz !< length scale of v in z direction (in gp)
	286	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nwx !< length scale of w in x direction (in gp)
	287	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nwy !< length scale of w in y direction (in gp)
	288	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nwz !< length scale of w in z direction (in gp)
[2259]	289
[4022]	290	REAL(wp) :: blend !< value to create gradually and smooth blending of Reynolds stress and length
	291	!< scales above the boundary layer
	292	REAL(wp) :: blend_coeff = -2.3_wp !< coefficient used to ensure that blending functions decreases to 1/10 after
	293	!< one length scale above ABL top
	294	REAL(wp) :: d_l !< blend_coeff/length_scale
	295	REAL(wp) :: length_scale !< length scale, default is 8 x minimum grid spacing
[3347]	296	REAL(wp) :: dt_stg_adjust = 300.0_wp !< time interval for adjusting turbulence statistics
	297	REAL(wp) :: dt_stg_call = 5.0_wp !< time interval for calling synthetic turbulence generator
	298	REAL(wp) :: scale_l !< scaling parameter used for turbulence parametrization - Obukhov length
	299	REAL(wp) :: scale_us !< scaling parameter used for turbulence parametrization - friction velocity
	300	REAL(wp) :: scale_wm !< scaling parameter used for turbulence parametrization - momentum scale
	301	REAL(wp) :: time_stg_adjust = 0.0_wp !< time counter for adjusting turbulence information
	302	REAL(wp) :: time_stg_call = 0.0_wp !< time counter for calling generator
	303
[4022]	304	REAL(wp), DIMENSION(3) :: mc_factor = 1.0_wp !< correction factor for the u,v,w-components to maintain original mass flux
[3347]	305
[4022]	306
[3347]	307	REAL(wp),DIMENSION(:), ALLOCATABLE :: r11 !< Reynolds parameter
	308	REAL(wp),DIMENSION(:), ALLOCATABLE :: r21 !< Reynolds parameter
	309	REAL(wp),DIMENSION(:), ALLOCATABLE :: r22 !< Reynolds parameter
	310	REAL(wp),DIMENSION(:), ALLOCATABLE :: r31 !< Reynolds parameter
	311	REAL(wp),DIMENSION(:), ALLOCATABLE :: r32 !< Reynolds parameter
	312	REAL(wp),DIMENSION(:), ALLOCATABLE :: r33 !< Reynolds parameter
	313
	314	REAL(wp), DIMENSION(:), ALLOCATABLE :: a11 !< coefficient for Lund rotation
	315	REAL(wp), DIMENSION(:), ALLOCATABLE :: a21 !< coefficient for Lund rotation
	316	REAL(wp), DIMENSION(:), ALLOCATABLE :: a22 !< coefficient for Lund rotation
	317	REAL(wp), DIMENSION(:), ALLOCATABLE :: a31 !< coefficient for Lund rotation
	318	REAL(wp), DIMENSION(:), ALLOCATABLE :: a32 !< coefficient for Lund rotation
	319	REAL(wp), DIMENSION(:), ALLOCATABLE :: a33 !< coefficient for Lund rotation
	320	REAL(wp), DIMENSION(:), ALLOCATABLE :: tu !< Lagrangian time scale of u
	321	REAL(wp), DIMENSION(:), ALLOCATABLE :: tv !< Lagrangian time scale of v
	322	REAL(wp), DIMENSION(:), ALLOCATABLE :: tw !< Lagrangian time scale of w
[2259]	323
[3347]	324	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: bux !< filter function for u in x direction
	325	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: buy !< filter function for u in y direction
	326	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: buz !< filter function for u in z direction
	327	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: bvx !< filter function for v in x direction
	328	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: bvy !< filter function for v in y direction
	329	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: bvz !< filter function for v in z direction
	330	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: bwx !< filter function for w in y direction
	331	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: bwy !< filter function for w in y direction
	332	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: bwz !< filter function for w in z direction
	333	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fu_xz !< velocity seed for u at xz plane
	334	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fuo_xz !< velocity seed for u at xz plane with new random number
	335	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fu_yz !< velocity seed for u at yz plane
	336	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fuo_yz !< velocity seed for u at yz plane with new random number
	337	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fv_xz !< velocity seed for v at xz plane
	338	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fvo_xz !< velocity seed for v at xz plane with new random number
	339	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fv_yz !< velocity seed for v at yz plane
	340	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fvo_yz !< velocity seed for v at yz plane with new random number
	341	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fw_xz !< velocity seed for w at xz plane
	342	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fwo_xz !< velocity seed for w at xz plane with new random number
	343	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fw_yz !< velocity seed for w at yz plane
	344	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: fwo_yz !< velocity seed for w at yz plane with new random number
	345
	346	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: dist_xz !< imposed disturbances at north/south boundary
	347	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: dist_yz !< imposed disturbances at north/south boundary
[2259]	348
	349	!
	350	!-- PALM interfaces:
[3347]	351	!-- Adjust time and lenght scales, Reynolds stress, and filter functions
	352	INTERFACE stg_adjust
	353	MODULE PROCEDURE stg_adjust
	354	END INTERFACE stg_adjust
	355	!
[2259]	356	!-- Input parameter checks to be done in check_parameters
	357	INTERFACE stg_check_parameters
	358	MODULE PROCEDURE stg_check_parameters
	359	END INTERFACE stg_check_parameters
	360
	361	!
	362	!-- Calculate filter functions
	363	INTERFACE stg_filter_func
	364	MODULE PROCEDURE stg_filter_func
	365	END INTERFACE stg_filter_func
	366
	367	!
[2938]	368	!-- Generate velocity seeds at south and north domain boundary
	369	INTERFACE stg_generate_seed_xz
	370	MODULE PROCEDURE stg_generate_seed_xz
	371	END INTERFACE stg_generate_seed_xz
	372	!
	373	!-- Generate velocity seeds at left and/or right domain boundary
[2259]	374	INTERFACE stg_generate_seed_yz
	375	MODULE PROCEDURE stg_generate_seed_yz
	376	END INTERFACE stg_generate_seed_yz
	377
	378	!
	379	!-- Output of information to the header file
	380	INTERFACE stg_header
	381	MODULE PROCEDURE stg_header
	382	END INTERFACE stg_header
	383
	384	!
	385	!-- Initialization actions
	386	INTERFACE stg_init
	387	MODULE PROCEDURE stg_init
	388	END INTERFACE stg_init
	389
	390	!
	391	!-- Main procedure of synth. turb. gen.
	392	INTERFACE stg_main
	393	MODULE PROCEDURE stg_main
	394	END INTERFACE stg_main
	395
	396	!
	397	!-- Reading of NAMELIST parameters
	398	INTERFACE stg_parin
	399	MODULE PROCEDURE stg_parin
	400	END INTERFACE stg_parin
	401
	402	!
	403	!-- Reading of parameters for restart runs
[2894]	404	INTERFACE stg_rrd_global
	405	MODULE PROCEDURE stg_rrd_global
	406	END INTERFACE stg_rrd_global
[2259]	407
	408	!
	409	!-- Writing of binary output for restart runs
[2894]	410	INTERFACE stg_wrd_global
	411	MODULE PROCEDURE stg_wrd_global
	412	END INTERFACE stg_wrd_global
[2259]	413
	414	SAVE
	415
	416	PRIVATE
	417
	418	!
	419	!-- Public interfaces
[3347]	420	PUBLIC stg_adjust, stg_check_parameters, stg_header, stg_init, stg_main, &
	421	stg_parin, stg_rrd_global, stg_wrd_global
[2259]	422
	423	!
	424	!-- Public variables
[3347]	425	PUBLIC dt_stg_call, dt_stg_adjust, id_stg_left, id_stg_north, &
	426	id_stg_right, id_stg_south, parametrize_inflow_turbulence, &
	427	time_stg_adjust, time_stg_call, use_syn_turb_gen
[2259]	428
	429
	430	CONTAINS
	431
	432
	433	!------------------------------------------------------------------------------!
	434	! Description:
	435	! ------------
	436	!> Check parameters routine for synthetic turbulence generator
	437	!------------------------------------------------------------------------------!
	438	SUBROUTINE stg_check_parameters
	439
	440	IMPLICIT NONE
	441
[3182]	442	IF ( .NOT. use_syn_turb_gen .AND. .NOT. rans_mode .AND. &
	443	nesting_offline ) THEN
[3376]	444	message_string = 'Synthetic turbulence generator is required ' // &
	445	'if offline nesting is applied and PALM operates ' // &
	446	'in LES mode.'
	447	CALL message( 'stg_check_parameters', 'PA0520', 0, 0, 0, 6, 0 )
[2938]	448	ENDIF
	449
[3182]	450	IF ( .NOT. use_syn_turb_gen .AND. child_domain &
[2938]	451	.AND. rans_mode_parent .AND. .NOT. rans_mode ) THEN
[3376]	452	message_string = 'Synthetic turbulence generator is required ' // &
[2938]	453	'when nesting is applied and parent operates in ' // &
	454	'RANS-mode but current child in LES mode.'
[3376]	455	CALL message( 'stg_check_parameters', 'PA0524', 1, 2, 0, 6, 0 )
[2938]	456	ENDIF
	457
[2776]	458	IF ( use_syn_turb_gen ) THEN
[2259]	459
[3579]	460	IF ( child_domain .AND. .NOT. rans_mode .AND. &
	461	.NOT. rans_mode_parent ) THEN
	462	message_string = 'Using synthetic turbulence generator ' // &
	463	'is not allowed in LES-LES nesting.'
	464	CALL message( 'stg_check_parameters', 'PA0620', 1, 2, 0, 6, 0 )
	465
	466	ENDIF
	467
	468	IF ( child_domain .AND. rans_mode .AND. &
	469	rans_mode_parent ) THEN
	470	message_string = 'Using synthetic turbulence generator ' // &
	471	'is not allowed in RANS-RANS nesting.'
	472	CALL message( 'stg_check_parameters', 'PA0621', 1, 2, 0, 6, 0 )
	473
	474	ENDIF
	475
[3182]	476	IF ( .NOT. nesting_offline .AND. .NOT. child_domain ) THEN
	477
[2938]	478	IF ( INDEX( initializing_actions, 'set_constant_profiles' ) == 0 &
	479	.AND. INDEX( initializing_actions, 'read_restart_data' ) == 0 ) THEN
	480	message_string = 'Using synthetic turbulence generator ' // &
[3579]	481	'requires %initializing_actions = ' // &
	482	'"set_constant_profiles" or "read_restart_data"' //&
	483	', if not offline nesting is applied.'
[2938]	484	CALL message( 'stg_check_parameters', 'PA0015', 1, 2, 0, 6, 0 )
	485	ENDIF
	486
	487	IF ( bc_lr /= 'dirichlet/radiation' ) THEN
	488	message_string = 'Using synthetic turbulence generator ' // &
[3347]	489	'requires &bc_lr = "dirichlet/radiation", ' // &
	490	'if not offline nesting is applied.'
[2938]	491	CALL message( 'stg_check_parameters', 'PA0035', 1, 2, 0, 6, 0 )
	492	ENDIF
	493	IF ( bc_ns /= 'cyclic' ) THEN
	494	message_string = 'Using synthetic turbulence generator ' // &
[3579]	495	'requires &bc_ns = "cyclic", ' // &
[3347]	496	'if not offline nesting is applied.'
[2938]	497	CALL message( 'stg_check_parameters', 'PA0037', 1, 2, 0, 6, 0 )
	498	ENDIF
	499
[2259]	500	ENDIF
	501
	502	IF ( turbulent_inflow ) THEN
	503	message_string = 'Using synthetic turbulence generator ' // &
[2938]	504	'in combination &with turbulent_inflow = .T. '// &
	505	'is not allowed'
[2259]	506	CALL message( 'stg_check_parameters', 'PA0039', 1, 2, 0, 6, 0 )
	507	ENDIF
[4309]	508	!
	509	!-- Synthetic turbulence generator requires the parallel random generator
	510	IF ( random_generator /= 'random-parallel' ) THEN
	511	message_string = 'Using synthetic turbulence generator ' // &
	512	'requires random_generator = random-parallel.'
	513	CALL message( 'stg_check_parameters', 'PA0421', 1, 2, 0, 6, 0 )
	514	ENDIF
[2259]	515
	516	ENDIF
	517
	518	END SUBROUTINE stg_check_parameters
	519
	520
	521	!------------------------------------------------------------------------------!
	522	! Description:
	523	! ------------
	524	!> Header output for synthetic turbulence generator
	525	!------------------------------------------------------------------------------!
	526	SUBROUTINE stg_header ( io )
	527
	528
	529	IMPLICIT NONE
	530
	531	INTEGER(iwp), INTENT(IN) :: io !< Unit of the output file
	532
	533	!
	534	!-- Write synthetic turbulence generator Header
	535	WRITE( io, 1 )
[2776]	536	IF ( use_syn_turb_gen ) THEN
[2259]	537	WRITE( io, 2 )
	538	ELSE
	539	WRITE( io, 3 )
	540	ENDIF
[3347]	541
	542	IF ( parametrize_inflow_turbulence ) THEN
	543	WRITE( io, 4 ) dt_stg_adjust
	544	ELSE
	545	WRITE( io, 5 )
	546	ENDIF
[2259]	547
	548	1 FORMAT (//' Synthetic turbulence generator information:'/ &
	549	' ------------------------------------------'/)
[3347]	550	2 FORMAT (' synthetic turbulence generator is switched on')
	551	3 FORMAT (' synthetic turbulence generator is switched off')
[3348]	552	4 FORMAT (' imposed turbulence statistics are parametrized and ajdusted to boundary-layer development each ', F8.2, ' s' )
[3347]	553	5 FORMAT (' imposed turbulence is read from file' )
[2259]	554
	555	END SUBROUTINE stg_header
	556
	557
	558	!------------------------------------------------------------------------------!
	559	! Description:
	560	! ------------
	561	!> Initialization of the synthetic turbulence generator
	562	!------------------------------------------------------------------------------!
	563	SUBROUTINE stg_init
	564
	565	IMPLICIT NONE
	566
[3347]	567	LOGICAL :: file_stg_exist = .FALSE. !< flag indicating whether parameter file for Reynolds stress and length scales exist
[2938]	568
[2669]	569	#if defined( __parallel )
[2259]	570	INTEGER(KIND=MPI_ADDRESS_KIND) :: extent !< extent of new MPI type
	571	INTEGER(KIND=MPI_ADDRESS_KIND) :: tob=0 !< dummy variable
[2669]	572	#endif
[2259]	573
[2938]	574	INTEGER(iwp) :: i !> grid index in x-direction
[2259]	575	INTEGER(iwp) :: j !> loop index
	576	INTEGER(iwp) :: k !< index
	577	INTEGER(iwp) :: newtype !< dummy MPI type
	578	INTEGER(iwp) :: realsize !< size of REAL variables
[4309]	579
[4022]	580	INTEGER(iwp), DIMENSION(3) :: nr_non_topo_xz_l = 0 !< number of non-topography grid points at xz-cross-section on subdomain
	581	INTEGER(iwp), DIMENSION(3) :: nr_non_topo_yz_l = 0 !< number of non-topography grid points at yz-cross-section on subdomain
[2259]	582	!
	583	!-- Dummy variables used for reading profiles
	584	REAL(wp) :: d1 !< u profile
	585	REAL(wp) :: d2 !< v profile
	586	REAL(wp) :: d3 !< w profile
	587	REAL(wp) :: d5 !< e profile
	588	REAL(wp) :: luy !< length scale for u in y direction
	589	REAL(wp) :: luz !< length scale for u in z direction
	590	REAL(wp) :: lvy !< length scale for v in y direction
	591	REAL(wp) :: lvz !< length scale for v in z direction
	592	REAL(wp) :: lwy !< length scale for w in y direction
	593	REAL(wp) :: lwz !< length scale for w in z direction
[3038]	594	REAL(wp) :: nnz !< increment used to determine processor decomposition of z-axis along x and y direction
[2259]	595	REAL(wp) :: zz !< height
	596
[2938]	597
[2259]	598	#if defined( __parallel )
	599	CALL MPI_BARRIER( comm2d, ierr )
	600	#endif
	601
[2669]	602	#if defined( __parallel )
[2259]	603	!
[2938]	604	!-- Determine processor decomposition of z-axis along x- and y-direction
	605	nnz = nz / pdims(1)
[2945]	606	nzb_x_stg = 1 + myidx * INT( nnz )
	607	nzt_x_stg = ( myidx + 1 ) * INT( nnz )
[2938]	608
[3038]	609	IF ( MOD( nz , pdims(1) ) /= 0 .AND. myidx == id_stg_right ) &
[2945]	610	nzt_x_stg = nzt_x_stg + myidx * ( nnz - INT( nnz ) )
[2938]	611
[3182]	612	IF ( nesting_offline .OR. ( child_domain .AND. rans_mode_parent &
	613	.AND. .NOT. rans_mode ) ) THEN
[2938]	614	nnz = nz / pdims(2)
[2945]	615	nzb_y_stg = 1 + myidy * INT( nnz )
	616	nzt_y_stg = ( myidy + 1 ) * INT( nnz )
[2938]	617
[2945]	618	IF ( MOD( nz , pdims(2) ) /= 0 .AND. myidy == id_stg_north ) &
[3038]	619	nzt_y_stg = nzt_y_stg + myidy * ( nnz - INT( nnz ) )
[2938]	620	ENDIF
	621
	622	!
[2259]	623	!-- Define MPI type used in stg_generate_seed_yz to gather vertical splitted
	624	!-- velocity seeds
	625	CALL MPI_TYPE_SIZE( MPI_REAL, realsize, ierr )
	626	extent = 1 * realsize
[2938]	627	!
[3038]	628	!-- Set-up MPI datatyp to involve all cores for turbulence generation at yz
	629	!-- layer
[2938]	630	!-- stg_type_yz: yz-slice with vertical bounds nzb:nzt+1
[2259]	631	CALL MPI_TYPE_CREATE_SUBARRAY( 2, [nzt-nzb+2,nyng-nysg+1], &
	632	[1,nyng-nysg+1], [0,0], MPI_ORDER_FORTRAN, MPI_REAL, newtype, ierr )
	633	CALL MPI_TYPE_CREATE_RESIZED( newtype, tob, extent, stg_type_yz, ierr )
	634	CALL MPI_TYPE_COMMIT( stg_type_yz, ierr )
	635	CALL MPI_TYPE_FREE( newtype, ierr )
	636
[2938]	637	! stg_type_yz_small: yz-slice with vertical bounds nzb_x_stg:nzt_x_stg+1
[2945]	638	CALL MPI_TYPE_CREATE_SUBARRAY( 2, [nzt_x_stg-nzb_x_stg+2,nyng-nysg+1], &
[2259]	639	[1,nyng-nysg+1], [0,0], MPI_ORDER_FORTRAN, MPI_REAL, newtype, ierr )
	640	CALL MPI_TYPE_CREATE_RESIZED( newtype, tob, extent, stg_type_yz_small, ierr )
	641	CALL MPI_TYPE_COMMIT( stg_type_yz_small, ierr )
	642	CALL MPI_TYPE_FREE( newtype, ierr )
	643
	644	! receive count and displacement for MPI_GATHERV in stg_generate_seed_yz
[2938]	645	ALLOCATE( recv_count_yz(pdims(1)), displs_yz(pdims(1)) )
[2259]	646
[2938]	647	recv_count_yz = nzt_x_stg-nzb_x_stg + 1
	648	recv_count_yz(pdims(1)) = recv_count_yz(pdims(1)) + 1
[2259]	649
	650	DO j = 1, pdims(1)
[2938]	651	displs_yz(j) = 0 + (nzt_x_stg-nzb_x_stg+1) * (j-1)
[2259]	652	ENDDO
[2938]	653	!
[3038]	654	!-- Set-up MPI datatyp to involve all cores for turbulence generation at xz
	655	!-- layer
[2938]	656	!-- stg_type_xz: xz-slice with vertical bounds nzb:nzt+1
[3182]	657	IF ( nesting_offline .OR. ( child_domain .AND. rans_mode_parent &
	658	.AND. .NOT. rans_mode ) ) THEN
[2945]	659	CALL MPI_TYPE_CREATE_SUBARRAY( 2, [nzt-nzb+2,nxrg-nxlg+1], &
[2938]	660	[1,nxrg-nxlg+1], [0,0], MPI_ORDER_FORTRAN, MPI_REAL, newtype, ierr )
	661	CALL MPI_TYPE_CREATE_RESIZED( newtype, tob, extent, stg_type_xz, ierr )
	662	CALL MPI_TYPE_COMMIT( stg_type_xz, ierr )
	663	CALL MPI_TYPE_FREE( newtype, ierr )
	664
	665	! stg_type_yz_small: xz-slice with vertical bounds nzb_x_stg:nzt_x_stg+1
[2945]	666	CALL MPI_TYPE_CREATE_SUBARRAY( 2, [nzt_y_stg-nzb_y_stg+2,nxrg-nxlg+1], &
[2938]	667	[1,nxrg-nxlg+1], [0,0], MPI_ORDER_FORTRAN, MPI_REAL, newtype, ierr )
	668	CALL MPI_TYPE_CREATE_RESIZED( newtype, tob, extent, stg_type_xz_small, ierr )
	669	CALL MPI_TYPE_COMMIT( stg_type_xz_small, ierr )
	670	CALL MPI_TYPE_FREE( newtype, ierr )
	671
	672	! receive count and displacement for MPI_GATHERV in stg_generate_seed_yz
	673	ALLOCATE( recv_count_xz(pdims(2)), displs_xz(pdims(2)) )
	674
	675	recv_count_xz = nzt_y_stg-nzb_y_stg + 1
	676	recv_count_xz(pdims(2)) = recv_count_xz(pdims(2)) + 1
	677
	678	DO j = 1, pdims(2)
	679	displs_xz(j) = 0 + (nzt_y_stg-nzb_y_stg+1) * (j-1)
	680	ENDDO
	681
	682	ENDIF
	683
[2669]	684	#endif
[2259]	685	!
[4071]	686	!-- Allocate required arrays.
	687	!-- In case no offline nesting or self nesting is used, the arrary
	688	!-- mean_inflow profiles is required. Check if it is already allocated, else
	689	!-- allocate and initialize it appropriately. Note, in case turbulence and
	690	!-- inflow information is read from file, mean_inflow_profiles is already
	691	!-- allocated and initialized appropriately.
[3347]	692	IF ( .NOT. nesting_offline .AND. .NOT. child_domain ) THEN
[4071]	693	IF ( .NOT. ALLOCATED( mean_inflow_profiles ) ) THEN
[3347]	694	ALLOCATE( mean_inflow_profiles(nzb:nzt+1,1:num_mean_inflow_profiles) )
[4071]	695	mean_inflow_profiles = 0.0_wp
	696	mean_inflow_profiles(:,1) = u_init
	697	mean_inflow_profiles(:,2) = v_init
	698	!
	699	!-- Even though potential temperature and humidity are not perturbed,
	700	!-- they need to be initialized appropriately.
	701	IF ( .NOT. neutral ) &
	702	mean_inflow_profiles(:,4) = pt_init
	703	IF ( humidity ) &
	704	mean_inflow_profiles(:,6) = q_init
	705	ENDIF
[3347]	706	ENDIF
[2259]	707
[3347]	708	ALLOCATE ( a11(nzb:nzt+1), a21(nzb:nzt+1), a22(nzb:nzt+1), &
	709	a31(nzb:nzt+1), a32(nzb:nzt+1), a33(nzb:nzt+1), &
	710	nux(nzb:nzt+1), nuy(nzb:nzt+1), nuz(nzb:nzt+1), &
	711	nvx(nzb:nzt+1), nvy(nzb:nzt+1), nvz(nzb:nzt+1), &
	712	nwx(nzb:nzt+1), nwy(nzb:nzt+1), nwz(nzb:nzt+1), &
	713	r11(nzb:nzt+1), r21(nzb:nzt+1), r22(nzb:nzt+1), &
	714	r31(nzb:nzt+1), r32(nzb:nzt+1), r33(nzb:nzt+1), &
	715	tu(nzb:nzt+1), tv(nzb:nzt+1), tw(nzb:nzt+1) )
	716
	717	ALLOCATE ( dist_xz(nzb:nzt+1,nxlg:nxrg,3) )
	718	ALLOCATE ( dist_yz(nzb:nzt+1,nysg:nyng,3) )
	719	dist_xz = 0.0_wp
	720	dist_yz = 0.0_wp
	721	!
[2259]	722	!-- Read inflow profile
	723	!-- Height levels of profiles in input profile is as follows:
	724	!-- zu: luy, luz, tu, lvy, lvz, tv, r11, r21, r22, d1, d2, d5
	725	!-- zw: lwy, lwz, tw, r31, r32, r33, d3
	726	!-- WARNING: zz is not used at the moment
[2938]	727	INQUIRE( FILE = 'STG_PROFILES' // TRIM( coupling_char ), &
	728	EXIST = file_stg_exist )
[2259]	729
[2938]	730	IF ( file_stg_exist ) THEN
[2259]	731
[2938]	732	OPEN( 90, FILE='STG_PROFILES'//TRIM( coupling_char ), STATUS='OLD', &
	733	FORM='FORMATTED')
	734	!
	735	!-- Skip header
	736	READ( 90, * )
[2259]	737
[3182]	738	DO k = nzb+1, nzt+1
[2938]	739	READ( 90, * ) zz, luy, luz, tu(k), lvy, lvz, tv(k), lwy, lwz, tw(k), &
	740	r11(k), r21(k), r22(k), r31(k), r32(k), r33(k), &
	741	d1, d2, d3, d5
	742
[2259]	743	!
[3182]	744	!-- Convert length scales from meter to number of grid points.
[2938]	745	nuy(k) = INT( luy * ddy )
[3182]	746	nuz(k) = INT( luz * ddzw(k) )
[2938]	747	nvy(k) = INT( lvy * ddy )
[3182]	748	nvz(k) = INT( lvz * ddzw(k) )
[2938]	749	nwy(k) = INT( lwy * ddy )
[3182]	750	nwz(k) = INT( lwz * ddzw(k) )
[2938]	751	!
	752	!-- Workaround, assume isotropic turbulence
	753	nwx(k) = nwy(k)
	754	nvx(k) = nvy(k)
	755	nux(k) = nuy(k)
	756	!
	757	!-- Save Mean inflow profiles
	758	IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN
	759	mean_inflow_profiles(k,1) = d1
	760	mean_inflow_profiles(k,2) = d2
	761	! mean_inflow_profiles(k,4) = d4
	762	mean_inflow_profiles(k,5) = d5
	763	ENDIF
	764	ENDDO
[3182]	765	!
	766	!-- Set lenght scales at surface grid point
	767	nuy(nzb) = nuy(nzb+1)
	768	nuz(nzb) = nuz(nzb+1)
	769	nvy(nzb) = nvy(nzb+1)
	770	nvz(nzb) = nvz(nzb+1)
	771	nwy(nzb) = nwy(nzb+1)
	772	nwz(nzb) = nwz(nzb+1)
	773
[2938]	774	CLOSE( 90 )
[3347]	775	!
	776	!-- Calculate coefficient matrix from Reynolds stress tensor
	777	!-- (Lund rotation)
	778	CALL calc_coeff_matrix
	779	!
	780	!-- No information about turbulence and its length scales are available.
	781	!-- Instead, parametrize turbulence which is imposed at the boundaries.
	782	!-- Set flag which indicates that turbulence is parametrized, which is done
	783	!-- later when energy-balance models are already initialized. This is
	784	!-- because the STG needs information about surface properties such as
	785	!-- roughness to build 'realistic' turbulence profiles.
[2938]	786	ELSE
[2259]	787	!
[4022]	788	!-- Define length scale for the imposed turbulence, which is defined as
	789	!-- 8 times the minimum grid spacing
	790	length_scale = 8.0_wp * MIN( dx, dy, MINVAL( dzw ) )
	791	!
	792	!-- Define constant to gradually decrease length scales and Reynolds stress
	793	!-- above ABL top. Assure that no zero length scales are used.
	794	d_l = blend_coeff / MAX( length_scale, dx, dy, MINVAL( dzw ) )
	795	!
[3347]	796	!-- Set flag indicating that turbulence is parametrized
	797	parametrize_inflow_turbulence = .TRUE.
	798	!
[4022]	799	!-- In case of dirichlet inflow boundary conditions only at one lateral
	800	!-- boundary, i.e. in the case no offline or self nesting is applied but
	801	!-- synthetic turbulence shall be parametrized nevertheless, the
	802	!-- boundary-layer depth need to determined first.
	803	IF ( .NOT. nesting_offline .AND. .NOT. child_domain ) &
	804	CALL nesting_offl_calc_zi
	805	!
[3347]	806	!-- Determine boundary-layer depth, which is used to initialize lenght
	807	!-- scales
	808	CALL calc_scaling_variables
	809	!
	810	!-- Initialize lenght and time scales, which in turn are used
	811	!-- to initialize the filter functions.
	812	CALL calc_length_and_time_scale
[3891]	813	!
	814	!-- Parametrize Reynolds-stress tensor, diagonal elements as well
	815	!-- as r21 (v'u'), r31 (w'u'), r32 (w'v'). Parametrization follows
	816	!-- Rotach et al. (1996) and is based on boundary-layer depth,
	817	!-- friction velocity and velocity scale.
	818	CALL parametrize_reynolds_stress
	819	!
	820	!-- Calculate coefficient matrix from Reynolds stress tensor
	821	!-- (Lund rotation)
	822	CALL calc_coeff_matrix
[3347]	823
[2938]	824	ENDIF
	825
[2259]	826	!
[3347]	827	!-- Assign initial profiles. Note, this is only required if turbulent
	828	!-- inflow from the left is desired, not in case of any of the
	829	!-- nesting (offline or self nesting) approaches.
[3182]	830	IF ( .NOT. nesting_offline .AND. .NOT. child_domain ) THEN
[2938]	831	u_init = mean_inflow_profiles(:,1)
	832	v_init = mean_inflow_profiles(:,2)
	833	!pt_init = mean_inflow_profiles(:,4)
	834	e_init = MAXVAL( mean_inflow_profiles(:,5) )
	835	ENDIF
[3347]	836
[2938]	837	!
[2259]	838	!-- Define the size of the filter functions and allocate them.
	839	merg = 0
	840
	841	! arrays must be large enough to cover the largest length scale
	842	DO k = nzb, nzt+1
[2938]	843	j = MAX( ABS(nux(k)), ABS(nuy(k)), ABS(nuz(k)), &
	844	ABS(nvx(k)), ABS(nvy(k)), ABS(nvz(k)), &
	845	ABS(nwx(k)), ABS(nwy(k)), ABS(nwz(k)) )
[2259]	846	IF ( j > merg ) merg = j
	847	ENDDO
	848
	849	merg = 2 * merg
	850	mergp = merg + nbgp
	851
[2938]	852	ALLOCATE ( bux(-merg:merg,nzb:nzt+1), &
	853	buy(-merg:merg,nzb:nzt+1), &
	854	buz(-merg:merg,nzb:nzt+1), &
	855	bvx(-merg:merg,nzb:nzt+1), &
	856	bvy(-merg:merg,nzb:nzt+1), &
	857	bvz(-merg:merg,nzb:nzt+1), &
	858	bwx(-merg:merg,nzb:nzt+1), &
	859	bwy(-merg:merg,nzb:nzt+1), &
	860	bwz(-merg:merg,nzb:nzt+1) )
[2259]	861
	862	!
[2938]	863	!-- Allocate velocity seeds for turbulence at xz-layer
	864	ALLOCATE ( fu_xz( nzb:nzt+1,nxlg:nxrg), fuo_xz(nzb:nzt+1,nxlg:nxrg), &
	865	fv_xz( nzb:nzt+1,nxlg:nxrg), fvo_xz(nzb:nzt+1,nxlg:nxrg), &
	866	fw_xz( nzb:nzt+1,nxlg:nxrg), fwo_xz(nzb:nzt+1,nxlg:nxrg) )
[2259]	867
[2938]	868	!
	869	!-- Allocate velocity seeds for turbulence at yz-layer
	870	ALLOCATE ( fu_yz( nzb:nzt+1,nysg:nyng), fuo_yz(nzb:nzt+1,nysg:nyng), &
	871	fv_yz( nzb:nzt+1,nysg:nyng), fvo_yz(nzb:nzt+1,nysg:nyng), &
	872	fw_yz( nzb:nzt+1,nysg:nyng), fwo_yz(nzb:nzt+1,nysg:nyng) )
[2259]	873
[2938]	874	fu_xz = 0.0_wp
	875	fuo_xz = 0.0_wp
	876	fv_xz = 0.0_wp
	877	fvo_xz = 0.0_wp
	878	fw_xz = 0.0_wp
	879	fwo_xz = 0.0_wp
	880
	881	fu_yz = 0.0_wp
	882	fuo_yz = 0.0_wp
	883	fv_yz = 0.0_wp
	884	fvo_yz = 0.0_wp
	885	fw_yz = 0.0_wp
	886	fwo_yz = 0.0_wp
	887
[2259]	888	!
	889	!-- Create filter functions
[2938]	890	CALL stg_filter_func( nux, bux ) !filter ux
[2259]	891	CALL stg_filter_func( nuy, buy ) !filter uy
	892	CALL stg_filter_func( nuz, buz ) !filter uz
[2938]	893	CALL stg_filter_func( nvx, bvx ) !filter vx
[2259]	894	CALL stg_filter_func( nvy, bvy ) !filter vy
	895	CALL stg_filter_func( nvz, bvz ) !filter vz
[2938]	896	CALL stg_filter_func( nwx, bwx ) !filter wx
[2259]	897	CALL stg_filter_func( nwy, bwy ) !filter wy
	898	CALL stg_filter_func( nwz, bwz ) !filter wz
	899
	900	#if defined( __parallel )
	901	CALL MPI_BARRIER( comm2d, ierr )
	902	#endif
	903
	904	!
[2938]	905	!-- In case of restart, calculate velocity seeds fu, fv, fw from former
	906	! time step.
	907	! Bug: fu, fv, fw are different in those heights where a11, a22, a33
	908	! are 0 compared to the prerun. This is mostly for k=nzt+1.
[2259]	909	IF ( TRIM( initializing_actions ) == 'read_restart_data' ) THEN
[2938]	910	IF ( myidx == id_stg_left .OR. myidx == id_stg_right ) THEN
	911
	912	IF ( myidx == id_stg_left ) i = -1
	913	IF ( myidx == id_stg_right ) i = nxr+1
	914
[2259]	915	DO j = nysg, nyng
	916	DO k = nzb, nzt+1
[4332]	917	IF ( a11(k) > 10E-8_wp ) THEN
[4022]	918	fu_yz(k,j) = ( u(k,j,i) - u_init(k) ) / a11(k)
[2259]	919	ELSE
[4332]	920	fu_yz(k,j) = 10E-8_wp
[2259]	921	ENDIF
	922
[4332]	923	IF ( a22(k) > 10E-8_wp ) THEN
[4022]	924	fv_yz(k,j) = ( v(k,j,i) - &
	925	a21(k) * fu_yz(k,j) - v_init(k) ) / a22(k)
[2259]	926	ELSE
[4332]	927	fv_yz(k,j) = 10E-8_wp
[2259]	928	ENDIF
	929
[4332]	930	IF ( a33(k) > 10E-8_wp ) THEN
[4022]	931	fw_yz(k,j) = ( w(k,j,i) - &
	932	a31(k) * fu_yz(k,j) - a32(k) * &
	933	fv_yz(k,j) ) / a33(k)
[2259]	934	ELSE
[4332]	935	fw_yz(k,j) = 10E-8_wp
[2259]	936	ENDIF
	937	ENDDO
	938	ENDDO
	939	ENDIF
[3900]	940
	941	IF ( myidy == id_stg_south .OR. myidy == id_stg_north ) THEN
	942
	943	IF ( myidy == id_stg_south ) j = -1
	944	IF ( myidy == id_stg_north ) j = nyn+1
	945
	946	DO i = nxlg, nxrg
	947	DO k = nzb, nzt+1
[4335]	948	!
	949	!-- In case the correlation coefficients are very small, the
	950	!-- velocity seeds may become very large finally creating
	951	!-- numerical instabilities in the synthetic turbulence generator.
	952	!-- Empirically, a value of 10E-8 seems to be sufficient.
[4332]	953	IF ( a11(k) > 10E-8_wp ) THEN
[4022]	954	fu_xz(k,i) = ( u(k,j,i) - u_init(k) ) / a11(k)
[3900]	955	ELSE
[4332]	956	fu_xz(k,i) = 10E-8_wp
[3900]	957	ENDIF
	958
[4332]	959	IF ( a22(k) > 10E-8_wp ) THEN
[4022]	960	fv_xz(k,i) = ( v(k,j,i) - &
	961	a21(k) * fu_xz(k,i) - v_init(k) ) / a22(k)
[3900]	962	ELSE
[4332]	963	fv_xz(k,i) = 10E-8_wp
[3900]	964	ENDIF
	965
[4332]	966	IF ( a33(k) > 10E-8_wp ) THEN
[4022]	967	fw_xz(k,i) = ( w(k,j,i) - &
	968	a31(k) * fu_xz(k,i) - &
	969	a32(k) * fv_xz(k,i) ) / a33(k)
[3900]	970	ELSE
[4332]	971	fw_xz(k,i) = 10E-8_wp
[3900]	972	ENDIF
	973
	974	ENDDO
	975	ENDDO
	976	ENDIF
[2259]	977	ENDIF
[4022]	978	!
	979	!-- Count the number of non-topography grid points at the boundaries where
	980	!-- perturbations are imposed. This number is later used for bias corrections
	981	!-- of the perturbations, i.e. to force that their mean is zero. Please note,
	982	!-- due to the asymetry of u and v along x and y direction, respectively,
	983	!-- different cases must be distinguished.
	984	IF ( myidx == id_stg_left .OR. myidx == id_stg_right ) THEN
	985	!
	986	!-- Number of grid points where perturbations are imposed on u
	987	IF ( myidx == id_stg_left ) i = nxl
	988	IF ( myidx == id_stg_right ) i = nxr+1
	989
	990	nr_non_topo_yz_l(1) = SUM( &
	991	MERGE( 1, 0, &
[4346]	992	BTEST( wall_flags_total_0(nzb:nzt,nys:nyn,i), 1 ) ) )
[4022]	993	!
	994	!-- Number of grid points where perturbations are imposed on v and w
	995	IF ( myidx == id_stg_left ) i = nxl-1
	996	IF ( myidx == id_stg_right ) i = nxr+1
	997
	998	nr_non_topo_yz_l(2) = SUM( &
	999	MERGE( 1, 0, &
[4346]	1000	BTEST( wall_flags_total_0(nzb:nzt,nysv:nyn,i), 2 ) ) )
[4022]	1001	nr_non_topo_yz_l(3) = SUM( &
	1002	MERGE( 1, 0, &
[4346]	1003	BTEST( wall_flags_total_0(nzb:nzt,nys:nyn,i), 3 ) ) )
[4022]	1004
	1005	#if defined( __parallel )
	1006	CALL MPI_ALLREDUCE( nr_non_topo_yz_l, nr_non_topo_yz, 3, MPI_INTEGER, &
	1007	MPI_SUM, comm1dy, ierr )
	1008	#else
	1009	nr_non_topo_yz = nr_non_topo_yz_l
	1010	#endif
	1011	ENDIF
	1012
	1013	IF ( myidy == id_stg_south .OR. myidy == id_stg_north ) THEN
	1014	!
	1015	!-- Number of grid points where perturbations are imposed on v
	1016	IF ( myidy == id_stg_south ) j = nys
	1017	IF ( myidy == id_stg_north ) j = nyn+1
	1018
	1019	nr_non_topo_xz_l(2) = SUM( &
	1020	MERGE( 1, 0, &
[4346]	1021	BTEST( wall_flags_total_0(nzb:nzt,j,nxl:nxr), 2 ) ) )
[4022]	1022	!
	1023	!-- Number of grid points where perturbations are imposed on u and w
	1024	IF ( myidy == id_stg_south ) j = nys-1
	1025	IF ( myidy == id_stg_north ) j = nyn+1
	1026
	1027	nr_non_topo_xz_l(1) = SUM( &
	1028	MERGE( 1, 0, &
[4346]	1029	BTEST( wall_flags_total_0(nzb:nzt,j,nxlu:nxr), 1 ) ) )
[4022]	1030	nr_non_topo_xz_l(3) = SUM( &
	1031	MERGE( 1, 0, &
[4346]	1032	BTEST( wall_flags_total_0(nzb:nzt,j,nxl:nxr), 3 ) ) )
[4022]	1033
	1034	#if defined( __parallel )
	1035	CALL MPI_ALLREDUCE( nr_non_topo_xz_l, nr_non_topo_xz, 3, MPI_INTEGER, &
	1036	MPI_SUM, comm1dx, ierr )
	1037	#else
	1038	nr_non_topo_xz = nr_non_topo_xz_l
	1039	#endif
	1040	ENDIF
[2259]	1041
[4022]	1042
[2259]	1043	END SUBROUTINE stg_init
	1044
	1045
	1046	!------------------------------------------------------------------------------!
	1047	! Description:
	1048	! ------------
	1049	!> Calculate filter function bxx from length scale nxx following Eg.9 and 10
	1050	!> (Xie and Castro, 2008)
	1051	!------------------------------------------------------------------------------!
	1052	SUBROUTINE stg_filter_func( nxx, bxx )
	1053
	1054
	1055	IMPLICIT NONE
	1056
	1057	INTEGER(iwp) :: k !< loop index
	1058	INTEGER(iwp) :: n_k !< length scale nXX in height k
	1059	INTEGER(iwp) :: n_k2 !< n_k * 2
	1060	INTEGER(iwp) :: nf !< index for length scales
	1061
	1062	REAL(wp) :: bdenom !< denominator for filter functions bXX
	1063	REAL(wp) :: qsi = 1.0_wp !< minimization factor
	1064
	1065	INTEGER(iwp), DIMENSION(:) :: nxx(nzb:nzt+1) !< length scale (in gp)
	1066
	1067	REAL(wp), DIMENSION(:,:) :: bxx(-merg:merg,nzb:nzt+1) !< filter function
	1068
	1069
	1070	bxx = 0.0_wp
	1071
	1072	DO k = nzb, nzt+1
	1073	bdenom = 0.0_wp
	1074	n_k = nxx(k)
	1075	IF ( n_k /= 0 ) THEN
	1076	n_k2 = n_k * 2
	1077
	1078	!
	1079	!-- ( Eq.10 )^2
	1080	DO nf = -n_k2, n_k2
	1081	bdenom = bdenom + EXP( -qsi * pi * ABS(nf) / n_k )**2
	1082	ENDDO
	1083
	1084	!
	1085	!-- ( Eq.9 )
	1086	bdenom = SQRT( bdenom )
	1087	DO nf = -n_k2, n_k2
	1088	bxx(nf,k) = EXP( -qsi * pi * ABS(nf) / n_k ) / bdenom
	1089	ENDDO
	1090	ENDIF
	1091	ENDDO
	1092
[3347]	1093	END SUBROUTINE stg_filter_func
[2259]	1094
	1095
	1096	!------------------------------------------------------------------------------!
	1097	! Description:
	1098	! ------------
	1099	!> Parin for &stg_par for synthetic turbulence generator
	1100	!------------------------------------------------------------------------------!
	1101	SUBROUTINE stg_parin
	1102
	1103
	1104	IMPLICIT NONE
	1105
	1106	CHARACTER (LEN=80) :: line !< dummy string that contains the current line of the parameter file
	1107
	1108
[3347]	1109	NAMELIST /stg_par/ dt_stg_adjust, dt_stg_call, use_syn_turb_gen
[2259]	1110
	1111	line = ' '
	1112
	1113	!
	1114	!-- Try to find stg package
	1115	REWIND ( 11 )
	1116	line = ' '
	1117	DO WHILE ( INDEX( line, '&stg_par' ) == 0 )
[3246]	1118	READ ( 11, '(A)', END=20 ) line
[2259]	1119	ENDDO
	1120	BACKSPACE ( 11 )
	1121
	1122	!
	1123	!-- Read namelist
[3246]	1124	READ ( 11, stg_par, ERR = 10, END = 20 )
[2259]	1125
	1126	!
	1127	!-- Set flag that indicates that the synthetic turbulence generator is switched
	1128	!-- on
[2776]	1129	syn_turb_gen = .TRUE.
[3246]	1130	GOTO 20
[2259]	1131
[3246]	1132	10 BACKSPACE( 11 )
[3248]	1133	READ( 11 , '(A)') line
	1134	CALL parin_fail_message( 'stg_par', line )
[2563]	1135
[3246]	1136	20 CONTINUE
[2259]	1137
	1138	END SUBROUTINE stg_parin
	1139
	1140
	1141	!------------------------------------------------------------------------------!
	1142	! Description:
	1143	! ------------
[2894]	1144	!> This routine reads the respective restart data.
[2576]	1145	!------------------------------------------------------------------------------!
[2894]	1146	SUBROUTINE stg_rrd_global( found )
[2576]	1147
	1148
[2894]	1149	IMPLICIT NONE
[2576]	1150
[3044]	1151	LOGICAL, INTENT(OUT) :: found !< flag indicating if variable was found
[2259]	1152
	1153
[2894]	1154	found = .TRUE.
[2259]	1155
[3038]	1156
[2894]	1157	SELECT CASE ( restart_string(1:length) )
[4022]	1158
	1159	CASE ( 'time_stg_adjust' )
	1160	READ ( 13 ) time_stg_adjust
	1161
	1162	CASE ( 'time_stg_call' )
	1163	READ ( 13 ) time_stg_call
	1164
[2894]	1165	CASE ( 'use_syn_turb_gen' )
	1166	READ ( 13 ) use_syn_turb_gen
[2259]	1167
[2894]	1168	CASE DEFAULT
[2259]	1169
[3038]	1170	found = .FALSE.
[2259]	1171
[2894]	1172	END SELECT
[2259]	1173
	1174
[2894]	1175	END SUBROUTINE stg_rrd_global
[2259]	1176
	1177
	1178	!------------------------------------------------------------------------------!
	1179	! Description:
	1180	! ------------
	1181	!> This routine writes the respective restart data.
	1182	!------------------------------------------------------------------------------!
[2894]	1183	SUBROUTINE stg_wrd_global
[2259]	1184
	1185
	1186	IMPLICIT NONE
[4022]	1187
	1188	CALL wrd_write_string( 'time_stg_adjust' )
	1189	WRITE ( 14 ) time_stg_adjust
	1190
	1191	CALL wrd_write_string( 'time_stg_call' )
	1192	WRITE ( 14 ) time_stg_call
[2259]	1193
[2894]	1194	CALL wrd_write_string( 'use_syn_turb_gen' )
	1195	WRITE ( 14 ) use_syn_turb_gen
[2259]	1196
	1197
[2894]	1198	END SUBROUTINE stg_wrd_global
[2259]	1199
[2894]	1200
[2259]	1201	!------------------------------------------------------------------------------!
	1202	! Description:
	1203	! ------------
	1204	!> Create turbulent inflow fields for u, v, w with prescribed length scales and
	1205	!> Reynolds stress tensor after a method of Xie and Castro (2008), modified
	1206	!> following suggestions of Kim et al. (2013), and using a Lund rotation
	1207	!> (Lund, 1998).
	1208	!------------------------------------------------------------------------------!
	1209	SUBROUTINE stg_main
	1210
	1211	IMPLICIT NONE
	1212
[2938]	1213	INTEGER(iwp) :: i !< grid index in x-direction
[2259]	1214	INTEGER(iwp) :: j !< loop index in y-direction
	1215	INTEGER(iwp) :: k !< loop index in z-direction
[4022]	1216
	1217	LOGICAL :: stg_call = .FALSE. !< control flag indicating whether turbulence was updated or only restored from last call
[2259]	1218
	1219	REAL(wp) :: dt_stg !< wheighted subtimestep
[4022]	1220
	1221	REAL(wp), DIMENSION(3) :: mc_factor_l !< local mass flux correction factor
[2259]	1222
[3987]	1223	IF ( debug_output_timestep ) CALL debug_message( 'stg_main', 'start' )
[2259]	1224	!
	1225	!-- Calculate time step which is needed for filter functions
[3775]	1226	dt_stg = MAX( dt_3d, dt_stg_call )
[2259]	1227	!
[4022]	1228	!-- Check if synthetic turbulence generator needs to be called and new
	1229	!-- perturbations need to be created or if old disturbances can be imposed
	1230	!-- again.
	1231	IF ( time_stg_call >= dt_stg_call .AND. &
	1232	intermediate_timestep_count == intermediate_timestep_count_max ) THEN
	1233	stg_call = .TRUE.
	1234	ELSE
	1235	stg_call = .FALSE.
	1236	ENDIF
	1237	!
[2259]	1238	!-- Initial value of fu, fv, fw
[3646]	1239	IF ( time_since_reference_point == 0.0_wp .AND. .NOT. velocity_seed_initialized ) THEN
[4309]	1240	!
	1241	!-- Generate turbulence at the left and right boundary. Random numbers
	1242	!-- for the yz-planes at the left/right boundary are generated by the
	1243	!-- left-sided mpi ranks only. After random numbers are calculated, they
	1244	!-- are distributed to all other mpi ranks in the model, so that the
	1245	!-- velocity seed matrices are available on all mpi ranks (i.e. also on the
	1246	!-- right-sided boundary mpi ranks). In case of offline nesting, this implies,
	1247	!-- that the left- and the right-sided lateral boundary have the same initial
	1248	!-- seeds.
	1249	!-- Note, in case of inflow from the right only, only turbulence at the left
	1250	!-- boundary is required.
	1251	IF ( .NOT. ( nesting_offline .OR. &
	1252	( child_domain .AND. rans_mode_parent &
	1253	.AND. .NOT. rans_mode ) ) ) THEN
[2938]	1254
[4309]	1255	CALL stg_generate_seed_yz( nuy, nuz, buy, buz, fu_yz, id_stg_left )
	1256	CALL stg_generate_seed_yz( nvy, nvz, bvy, bvz, fv_yz, id_stg_left )
	1257	CALL stg_generate_seed_yz( nwy, nwz, bwy, bwz, fw_yz, id_stg_left )
	1258	ELSE
	1259	CALL stg_generate_seed_yz( nuy, nuz, buy, buz, fu_yz, &
	1260	id_stg_left, id_stg_right )
	1261	CALL stg_generate_seed_yz( nvy, nvz, bvy, bvz, fv_yz, &
	1262	id_stg_left, id_stg_right )
	1263	CALL stg_generate_seed_yz( nwy, nwz, bwy, bwz, fw_yz, &
	1264	id_stg_left, id_stg_right )
[2938]	1265	!
[4309]	1266	!-- Generate turbulence at the south and north boundary. Random numbers
	1267	!-- for the xz-planes at the south/north boundary are generated by the
	1268	!-- south-sided mpi ranks only. Please see also comment above.
	1269	CALL stg_generate_seed_xz( nux, nuz, bux, buz, fu_xz, &
	1270	id_stg_south, id_stg_north )
	1271	CALL stg_generate_seed_xz( nvx, nvz, bvx, bvz, fv_xz, &
	1272	id_stg_south, id_stg_north )
	1273	CALL stg_generate_seed_xz( nwx, nwz, bwx, bwz, fw_xz, &
	1274	id_stg_south, id_stg_north )
[2938]	1275	ENDIF
[2259]	1276	velocity_seed_initialized = .TRUE.
	1277	ENDIF
	1278	!
[4309]	1279	!-- New set of fu, fv, fw. Note, for inflow from the left side only, velocity
	1280	!-- seeds are only required at the left boundary, while in case of offline
	1281	!-- nesting or RANS-LES nesting velocity seeds are required also at the
	1282	!-- right, south and north boundaries.
[4022]	1283	IF ( stg_call ) THEN
[4309]	1284	IF ( .NOT. ( nesting_offline .OR. &
	1285	( child_domain .AND. rans_mode_parent &
	1286	.AND. .NOT. rans_mode ) ) ) THEN
	1287	CALL stg_generate_seed_yz( nuy, nuz, buy, buz, fuo_yz, id_stg_left )
	1288	CALL stg_generate_seed_yz( nvy, nvz, bvy, bvz, fvo_yz, id_stg_left )
	1289	CALL stg_generate_seed_yz( nwy, nwz, bwy, bwz, fwo_yz, id_stg_left )
	1290
	1291	ELSE
	1292	CALL stg_generate_seed_yz( nuy, nuz, buy, buz, fuo_yz, &
	1293	id_stg_left, id_stg_right )
	1294	CALL stg_generate_seed_yz( nvy, nvz, bvy, bvz, fvo_yz, &
	1295	id_stg_left, id_stg_right )
	1296	CALL stg_generate_seed_yz( nwy, nwz, bwy, bwz, fwo_yz, &
	1297	id_stg_left, id_stg_right )
	1298
	1299	CALL stg_generate_seed_xz( nux, nuz, bux, buz, fuo_xz, &
	1300	id_stg_south, id_stg_north )
	1301	CALL stg_generate_seed_xz( nvx, nvz, bvx, bvz, fvo_xz, &
	1302	id_stg_south, id_stg_north )
	1303	CALL stg_generate_seed_xz( nwx, nwz, bwx, bwz, fwo_xz, &
	1304	id_stg_south, id_stg_north )
[4022]	1305	ENDIF
[2938]	1306	ENDIF
[3347]	1307
[2938]	1308	!
[4309]	1309	!-- Turbulence generation at left and/or right boundary
[2938]	1310	IF ( myidx == id_stg_left .OR. myidx == id_stg_right ) THEN
[2259]	1311	!
[4022]	1312	!-- Calculate new set of perturbations. Do this only at last RK3-substep and
	1313	!-- when dt_stg_call is exceeded. Else the old set of perturbations is
	1314	!-- imposed
	1315	IF ( stg_call ) THEN
	1316
	1317	DO j = nysg, nyng
	1318	DO k = nzb, nzt + 1
	1319	!
	1320	!-- Update fu, fv, fw following Eq. 14 of Xie and Castro (2008)
	1321	IF ( tu(k) == 0.0_wp ) THEN
	1322	fu_yz(k,j) = fuo_yz(k,j)
	1323	ELSE
	1324	fu_yz(k,j) = fu_yz(k,j) * EXP( -pi * dt_stg * 0.5_wp / tu(k) ) + &
	1325	fuo_yz(k,j) * SQRT( 1.0_wp - EXP( -pi * dt_stg / tu(k) ) )
	1326	ENDIF
	1327
	1328	IF ( tv(k) == 0.0_wp ) THEN
	1329	fv_yz(k,j) = fvo_yz(k,j)
	1330	ELSE
	1331	fv_yz(k,j) = fv_yz(k,j) * EXP( -pi * dt_stg * 0.5_wp / tv(k) ) + &
	1332	fvo_yz(k,j) * SQRT( 1.0_wp - EXP( -pi * dt_stg / tv(k) ) )
	1333	ENDIF
	1334
	1335	IF ( tw(k) == 0.0_wp ) THEN
	1336	fw_yz(k,j) = fwo_yz(k,j)
	1337	ELSE
	1338	fw_yz(k,j) = fw_yz(k,j) * EXP( -pi * dt_stg * 0.5_wp / tw(k) ) + &
	1339	fwo_yz(k,j) * SQRT( 1.0_wp - EXP( -pi * dt_stg / tw(k) ) )
	1340	ENDIF
	1341	ENDDO
	1342	ENDDO
	1343
	1344	dist_yz(nzb,:,1) = 0.0_wp
	1345	dist_yz(nzb,:,2) = 0.0_wp
	1346	dist_yz(nzb,:,3) = 0.0_wp
	1347
	1348	IF ( myidx == id_stg_left ) i = nxl
	1349	IF ( myidx == id_stg_right ) i = nxr+1
	1350	DO j = nysg, nyng
	1351	DO k = nzb+1, nzt + 1
	1352	!
	1353	!-- Lund rotation following Eq. 17 in Xie and Castro (2008).
	1354	!-- Additional factors are added to improve the variance of v and w
	1355	dist_yz(k,j,1) = MIN( a11(k) * fu_yz(k,j), 3.0_wp ) * &
	1356	MERGE( 1.0_wp, 0.0_wp, &
[4346]	1357	BTEST( wall_flags_total_0(k,j,i), 1 ) )
[4022]	1358	ENDDO
	1359	ENDDO
[4309]	1360
[4022]	1361	IF ( myidx == id_stg_left ) i = nxl-1
	1362	IF ( myidx == id_stg_right ) i = nxr+1
	1363	DO j = nysg, nyng
	1364	DO k = nzb+1, nzt + 1
	1365	!
	1366	!-- Lund rotation following Eq. 17 in Xie and Castro (2008).
	1367	!-- Additional factors are added to improve the variance of v and w
	1368	!-- experimental test of 1.2
[3347]	1369	dist_yz(k,j,2) = MIN( ( SQRT( a22(k) / MAXVAL(a22) ) &
	1370	* 1.2_wp ) &
	1371	* ( a21(k) * fu_yz(k,j) &
[4022]	1372	+ a22(k) * fv_yz(k,j) ), 3.0_wp ) * &
	1373	MERGE( 1.0_wp, 0.0_wp, &
[4346]	1374	BTEST( wall_flags_total_0(k,j,i), 2 ) )
[3347]	1375	dist_yz(k,j,3) = MIN( ( SQRT(a33(k) / MAXVAL(a33) ) &
	1376	* 1.3_wp ) &
	1377	* ( a31(k) * fu_yz(k,j) &
	1378	+ a32(k) * fv_yz(k,j) &
[4022]	1379	+ a33(k) * fw_yz(k,j) ), 3.0_wp ) * &
	1380	MERGE( 1.0_wp, 0.0_wp, &
[4346]	1381	BTEST( wall_flags_total_0(k,j,i), 3 ) )
[4022]	1382	ENDDO
[2259]	1383	ENDDO
[4022]	1384	ENDIF
[2259]	1385	!
	1386	!-- Mass flux correction following Kim et al. (2013)
	1387	!-- This correction factor insures that the mass flux is preserved at the
[4022]	1388	!-- inflow boundary. First, calculate mean value of the imposed
	1389	!-- perturbations at yz boundary.
	1390	!-- Note, this needs to be done only after the last RK3-substep, else
	1391	!-- the boundary values won't be accessed.
	1392	IF ( intermediate_timestep_count == intermediate_timestep_count_max ) THEN
	1393	mc_factor_l = 0.0_wp
	1394	mc_factor = 0.0_wp
	1395	!
	1396	!-- Sum up the original volume flows (with and without perturbations).
	1397	!-- Note, for non-normal components (here v and w) it is actually no
	1398	!-- volume flow.
[2938]	1399	IF ( myidx == id_stg_left ) i = nxl
	1400	IF ( myidx == id_stg_right ) i = nxr+1
[4022]	1401
	1402	mc_factor_l(1) = SUM( dist_yz(nzb:nzt,nys:nyn,1) &
	1403	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1404	BTEST( wall_flags_total_0(nzb:nzt,nys:nyn,i), 1 ) ) )
[4022]	1405
	1406	IF ( myidx == id_stg_left ) i = nxl-1
	1407	IF ( myidx == id_stg_right ) i = nxr+1
	1408
	1409	mc_factor_l(2) = SUM( dist_yz(nzb:nzt,nysv:nyn,2) &
	1410	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1411	BTEST( wall_flags_total_0(nzb:nzt,nysv:nyn,i), 2 ) ) )
[4022]	1412	mc_factor_l(3) = SUM( dist_yz(nzb:nzt,nys:nyn,3) &
	1413	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1414	BTEST( wall_flags_total_0(nzb:nzt,nys:nyn,i), 3 ) ) )
[4022]	1415
[2938]	1416	#if defined( __parallel )
	1417	CALL MPI_ALLREDUCE( mc_factor_l, mc_factor, &
[4022]	1418	3, MPI_REAL, MPI_SUM, comm1dy, ierr )
	1419	#else
	1420	mc_factor = mc_factor_l
[2938]	1421	#endif
[4022]	1422	!
	1423	!-- Calculate correction factor and force zero mean perturbations.
	1424	mc_factor = mc_factor / REAL( nr_non_topo_yz, KIND = wp )
	1425
	1426	IF ( myidx == id_stg_left ) i = nxl
	1427	IF ( myidx == id_stg_right ) i = nxr+1
	1428
	1429	dist_yz(:,:,1) = ( dist_yz(:,:,1) - mc_factor(1) ) &
	1430	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1431	BTEST( wall_flags_total_0(:,:,i), 1 ) )
[4022]	1432
	1433
	1434	IF ( myidx == id_stg_left ) i = nxl-1
	1435	IF ( myidx == id_stg_right ) i = nxr+1
	1436
	1437	dist_yz(:,:,2) = ( dist_yz(:,:,2) - mc_factor(2) ) &
	1438	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1439	BTEST( wall_flags_total_0(:,:,i), 2 ) )
[4022]	1440
	1441	dist_yz(:,:,3) = ( dist_yz(:,:,3) - mc_factor(3) ) &
	1442	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1443	BTEST( wall_flags_total_0(:,:,i), 3 ) )
[4022]	1444	!
[2938]	1445	!-- Add disturbances
	1446	IF ( myidx == id_stg_left ) THEN
[4022]	1447	!
	1448	!-- For the left boundary distinguish between mesoscale offline / self
	1449	!-- nesting and turbulent inflow at the left boundary only. In the latter
	1450	!-- case turbulence is imposed on the mean inflow profiles.
	1451	IF ( .NOT. nesting_offline .AND. .NOT. child_domain ) THEN
	1452	!
	1453	!-- Add disturbance at the inflow
	1454	DO j = nysg, nyng
	1455	DO k = nzb, nzt+1
	1456	u(k,j,-nbgp+1:0) = ( mean_inflow_profiles(k,1) + &
	1457	dist_yz(k,j,1) ) &
	1458	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1459	BTEST( wall_flags_total_0(k,j,0), 1 ) )
[4022]	1460	v(k,j,-nbgp:-1) = ( mean_inflow_profiles(k,2) + &
	1461	dist_yz(k,j,2) ) &
	1462	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1463	BTEST( wall_flags_total_0(k,j,-1), 2 ) )
[4022]	1464	w(k,j,-nbgp:-1) = dist_yz(k,j,3) &
	1465	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1466	BTEST( wall_flags_total_0(k,j,-1), 3 ) )
[4022]	1467	ENDDO
[2938]	1468	ENDDO
[4022]	1469	ELSE
	1470
	1471	DO j = nys, nyn
	1472	DO k = nzb+1, nzt
	1473	u(k,j,0) = ( u(k,j,0) + dist_yz(k,j,1) ) &
	1474	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1475	BTEST( wall_flags_total_0(k,j,0), 1 ) )
[4022]	1476	u(k,j,-1) = u(k,j,0)
	1477	v(k,j,-1) = ( v(k,j,-1) + dist_yz(k,j,2) ) &
	1478	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1479	BTEST( wall_flags_total_0(k,j,-1), 2 ) )
[4022]	1480	w(k,j,-1) = ( w(k,j,-1) + dist_yz(k,j,3) ) &
	1481	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1482	BTEST( wall_flags_total_0(k,j,-1), 3 ) )
[4022]	1483	ENDDO
	1484	ENDDO
	1485	ENDIF
[2938]	1486	ENDIF
	1487	IF ( myidx == id_stg_right ) THEN
[3186]	1488	DO j = nys, nyn
[3347]	1489	DO k = nzb+1, nzt
[3186]	1490	u(k,j,nxr+1) = ( u(k,j,nxr+1) + dist_yz(k,j,1) ) &
[4022]	1491	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1492	BTEST( wall_flags_total_0(k,j,nxr+1), 1 ) )
[3186]	1493	v(k,j,nxr+1) = ( v(k,j,nxr+1) + dist_yz(k,j,2) ) &
[4022]	1494	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1495	BTEST( wall_flags_total_0(k,j,nxr+1), 2 ) )
[3186]	1496	w(k,j,nxr+1) = ( w(k,j,nxr+1) + dist_yz(k,j,3) ) &
[4022]	1497	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1498	BTEST( wall_flags_total_0(k,j,nxr+1), 3 ) )
[2938]	1499	ENDDO
	1500	ENDDO
	1501	ENDIF
	1502	ENDIF
	1503	ENDIF
	1504	!
	1505	!-- Turbulence generation at north and south boundary
	1506	IF ( myidy == id_stg_north .OR. myidy == id_stg_south ) THEN
	1507	!
[4022]	1508	!-- Calculate new set of perturbations. Do this only at last RK3-substep and
	1509	!-- when dt_stg_call is exceeded. Else the old set of perturbations is
	1510	!-- imposed
	1511	IF ( stg_call ) THEN
	1512	DO i = nxlg, nxrg
	1513	DO k = nzb, nzt + 1
	1514	!
	1515	!-- Update fu, fv, fw following Eq. 14 of Xie and Castro (2008)
	1516	IF ( tu(k) == 0.0_wp ) THEN
	1517	fu_xz(k,i) = fuo_xz(k,i)
	1518	ELSE
	1519	fu_xz(k,i) = fu_xz(k,i) * EXP( -pi * dt_stg * 0.5_wp / tu(k) ) + &
	1520	fuo_xz(k,i) * SQRT( 1.0_wp - EXP( -pi * dt_stg / tu(k) ) )
	1521	ENDIF
	1522
	1523	IF ( tv(k) == 0.0_wp ) THEN
	1524	fv_xz(k,i) = fvo_xz(k,i)
	1525	ELSE
	1526	fv_xz(k,i) = fv_xz(k,i) * EXP( -pi * dt_stg * 0.5_wp / tv(k) ) + &
	1527	fvo_xz(k,i) * SQRT( 1.0_wp - EXP( -pi * dt_stg / tv(k) ) )
	1528	ENDIF
	1529
	1530	IF ( tw(k) == 0.0_wp ) THEN
	1531	fw_xz(k,i) = fwo_xz(k,i)
	1532	ELSE
	1533	fw_xz(k,i) = fw_xz(k,i) * EXP( -pi * dt_stg * 0.5_wp / tw(k) ) + &
	1534	fwo_xz(k,i) * SQRT( 1.0_wp - EXP( -pi * dt_stg / tw(k) ) )
	1535	ENDIF
	1536	ENDDO
	1537	ENDDO
	1538
	1539
	1540	dist_xz(nzb,:,1) = 0.0_wp
	1541	dist_xz(nzb,:,2) = 0.0_wp
	1542	dist_xz(nzb,:,3) = 0.0_wp
	1543
	1544	IF ( myidy == id_stg_south ) j = nys
	1545	IF ( myidy == id_stg_north ) j = nyn+1
	1546	DO i = nxlg, nxrg
	1547	DO k = nzb+1, nzt + 1
	1548	!
	1549	!-- Lund rotation following Eq. 17 in Xie and Castro (2008).
	1550	!-- Additional factors are added to improve the variance of v and w
	1551	!experimental test of 1.2
[3347]	1552	dist_xz(k,i,2) = MIN( ( SQRT( a22(k) / MAXVAL(a22) ) &
	1553	* 1.2_wp ) &
	1554	* ( a21(k) * fu_xz(k,i) &
[4022]	1555	+ a22(k) * fv_xz(k,i) ), 3.0_wp ) * &
	1556	MERGE( 1.0_wp, 0.0_wp, &
[4346]	1557	BTEST( wall_flags_total_0(k,j,i), 2 ) )
[4022]	1558	ENDDO
	1559	ENDDO
	1560
	1561	IF ( myidy == id_stg_south ) j = nys-1
	1562	IF ( myidy == id_stg_north ) j = nyn+1
	1563	DO i = nxlg, nxrg
	1564	DO k = nzb+1, nzt + 1
	1565	!
	1566	!-- Lund rotation following Eq. 17 in Xie and Castro (2008).
	1567	!-- Additional factors are added to improve the variance of v and w
	1568	dist_xz(k,i,1) = MIN( a11(k) * fu_xz(k,i), 3.0_wp ) * &
	1569	MERGE( 1.0_wp, 0.0_wp, &
[4346]	1570	BTEST( wall_flags_total_0(k,j,i), 1 ) )
[4022]	1571
[3347]	1572	dist_xz(k,i,3) = MIN( ( SQRT(a33(k) / MAXVAL(a33) ) &
	1573	* 1.3_wp ) &
	1574	* ( a31(k) * fu_xz(k,i) &
	1575	+ a32(k) * fv_xz(k,i) &
[4022]	1576	+ a33(k) * fw_xz(k,i) ), 3.0_wp ) * &
	1577	MERGE( 1.0_wp, 0.0_wp, &
[4346]	1578	BTEST( wall_flags_total_0(k,j,i), 3 ) )
[4022]	1579	ENDDO
[2938]	1580	ENDDO
[4022]	1581	ENDIF
[3347]	1582
[2938]	1583	!
	1584	!-- Mass flux correction following Kim et al. (2013)
	1585	!-- This correction factor insures that the mass flux is preserved at the
[4022]	1586	!-- inflow boundary. First, calculate mean value of the imposed
	1587	!-- perturbations at yz boundary.
	1588	!-- Note, this needs to be done only after the last RK3-substep, else
	1589	!-- the boundary values won't be accessed.
	1590	IF ( intermediate_timestep_count == intermediate_timestep_count_max ) THEN
	1591	mc_factor_l = 0.0_wp
	1592	mc_factor = 0.0_wp
	1593
	1594	IF ( myidy == id_stg_south ) j = nys
	1595	IF ( myidy == id_stg_north ) j = nyn+1
	1596
	1597	mc_factor_l(2) = SUM( dist_xz(nzb:nzt,nxl:nxr,2) &
	1598	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1599	BTEST( wall_flags_total_0(nzb:nzt,j,nxl:nxr), 2 ) ) )
[4022]	1600
	1601	IF ( myidy == id_stg_south ) j = nys-1
	1602	IF ( myidy == id_stg_north ) j = nyn+1
	1603
	1604	mc_factor_l(1) = SUM( dist_xz(nzb:nzt,nxlu:nxr,1) &
	1605	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1606	BTEST( wall_flags_total_0(nzb:nzt,j,nxlu:nxr), 1 ) ) )
[4022]	1607	mc_factor_l(3) = SUM( dist_xz(nzb:nzt,nxl:nxr,3) &
	1608	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1609	BTEST( wall_flags_total_0(nzb:nzt,j,nxl:nxr), 3 ) ) )
[4022]	1610
[2938]	1611	#if defined( __parallel )
[4022]	1612	CALL MPI_ALLREDUCE( mc_factor_l, mc_factor, &
	1613	3, MPI_REAL, MPI_SUM, comm1dx, ierr )
	1614	#else
	1615	mc_factor = mc_factor_l
[2938]	1616	#endif
[4022]	1617
	1618	mc_factor = mc_factor / REAL( nr_non_topo_xz, KIND = wp )
	1619
	1620	IF ( myidy == id_stg_south ) j = nys
	1621	IF ( myidy == id_stg_north ) j = nyn+1
	1622
	1623	dist_xz(:,:,2) = ( dist_xz(:,:,2) - mc_factor(2) ) &
	1624	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1625	BTEST( wall_flags_total_0(:,j,:), 2 ) )
[4022]	1626
	1627
	1628	IF ( myidy == id_stg_south ) j = nys-1
	1629	IF ( myidy == id_stg_north ) j = nyn+1
	1630
	1631	dist_xz(:,:,1) = ( dist_xz(:,:,1) - mc_factor(1) ) &
	1632	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1633	BTEST( wall_flags_total_0(:,j,:), 1 ) )
[4022]	1634
	1635	dist_xz(:,:,3) = ( dist_xz(:,:,3) - mc_factor(3) ) &
	1636	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1637	BTEST( wall_flags_total_0(:,j,:), 3 ) )
[4022]	1638	!
	1639	!-- Add disturbances
	1640	IF ( myidy == id_stg_south ) THEN
	1641	DO i = nxl, nxr
	1642	DO k = nzb+1, nzt
	1643	u(k,-1,i) = ( u(k,-1,i) + dist_xz(k,i,1) ) &
	1644	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1645	BTEST( wall_flags_total_0(k,-1,i), 1 ) )
[4022]	1646	v(k,0,i) = ( v(k,0,i) + dist_xz(k,i,2) ) &
	1647	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1648	BTEST( wall_flags_total_0(k,0,i), 2 ) )
[4022]	1649	v(k,-1,i) = v(k,0,i)
	1650	w(k,-1,i) = ( w(k,-1,i) + dist_xz(k,i,3) ) &
	1651	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1652	BTEST( wall_flags_total_0(k,-1,i), 3 ) )
[4022]	1653	ENDDO
[2938]	1654	ENDDO
[4022]	1655	ENDIF
	1656	IF ( myidy == id_stg_north ) THEN
	1657
	1658	DO i = nxl, nxr
	1659	DO k = nzb+1, nzt
	1660	u(k,nyn+1,i) = ( u(k,nyn+1,i) + dist_xz(k,i,1) ) &
	1661	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1662	BTEST( wall_flags_total_0(k,nyn+1,i), 1 ) )
[4022]	1663	v(k,nyn+1,i) = ( v(k,nyn+1,i) + dist_xz(k,i,2) ) &
	1664	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1665	BTEST( wall_flags_total_0(k,nyn+1,i), 2 ) )
[4022]	1666	w(k,nyn+1,i) = ( w(k,nyn+1,i) + dist_xz(k,i,3) ) &
	1667	* MERGE( 1.0_wp, 0.0_wp, &
[4346]	1668	BTEST( wall_flags_total_0(k,nyn+1,i), 3 ) )
[4022]	1669	ENDDO
[2938]	1670	ENDDO
[4022]	1671	ENDIF
[2938]	1672	ENDIF
[2259]	1673	ENDIF
[3347]	1674	!
	1675	!-- Finally, set time counter for calling STG to zero
[4022]	1676	IF ( stg_call ) time_stg_call = 0.0_wp
[2259]	1677
[3987]	1678	IF ( debug_output_timestep ) CALL debug_message( 'stg_main', 'end' )
	1679
[2259]	1680	END SUBROUTINE stg_main
	1681
	1682	!------------------------------------------------------------------------------!
	1683	! Description:
	1684	! ------------
	1685	!> Generate a set of random number rand_it wich is equal on each PE
	1686	!> and calculate the velocity seed f_n.
	1687	!> f_n is splitted in vertical direction by the number of PEs in x-direction and
	1688	!> and each PE calculates a vertical subsection of f_n. At the the end, all
	1689	!> parts are collected to form the full array.
	1690	!------------------------------------------------------------------------------!
[4309]	1691	SUBROUTINE stg_generate_seed_yz( n_y, n_z, b_y, b_z, f_n, id_left, id_right )
	1692
	1693	USE pegrid
[2259]	1694
	1695	IMPLICIT NONE
	1696
[4309]	1697	INTEGER(iwp) :: i !< grid index x-direction
	1698	INTEGER(iwp) :: id_left !< core ids at respective boundaries
	1699	INTEGER(iwp), OPTIONAL :: id_right !< core ids at respective boundaries
	1700	INTEGER(iwp) :: j !< loop index in y-direction
	1701	INTEGER(iwp) :: jj !< loop index in y-direction
	1702	INTEGER(iwp) :: k !< loop index in z-direction
	1703	INTEGER(iwp) :: kk !< loop index in z-direction
	1704	INTEGER(iwp) :: send_count !< send count for MPI_GATHERV
[2259]	1705
	1706	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_y !< length scale in y-direction
	1707	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_z !< length scale in z-direction
	1708	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_y2 !< n_y*2
	1709	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_z2 !< n_z*2
	1710
	1711	REAL(wp) :: nyz_inv !< inverse of number of grid points in yz-slice
	1712	REAL(wp) :: rand_av !< average of random number
	1713	REAL(wp) :: rand_sigma_inv !< inverse of stdev of random number
	1714
[3347]	1715	REAL(wp), DIMENSION(-merg:merg,nzb:nzt+1) :: b_y !< filter function in y-direction
	1716	REAL(wp), DIMENSION(-merg:merg,nzb:nzt+1) :: b_z !< filter function in z-direction
[4309]	1717
[2938]	1718	REAL(wp), DIMENSION(nzb_x_stg:nzt_x_stg+1,nysg:nyng) :: f_n_l !< local velocity seed
[4309]	1719	REAL(wp), DIMENSION(nzb:nzt+1,nysg:nyng) :: f_n !< velocity seed
	1720
	1721	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rand_it !< global array of random numbers
	1722	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rand_it_l !< local array of random numbers
[2259]	1723
	1724	!
[4309]	1725	!-- Generate random numbers using the parallel random generator.
[2259]	1726	!-- The set of random numbers are modified to have an average of 0 and
[4309]	1727	!-- unit variance. Note, at the end the random number array must be defined
	1728	!-- globally in order to compute the correlation matrices. However,
	1729	!-- the calculation and normalization of random numbers is done locally,
	1730	!-- while the result is later distributed to all processes. Further,
	1731	!-- please note, a set of random numbers is only calculated for the
	1732	!-- left boundary, while the right boundary uses the same random numbers
	1733	!-- and thus also computes the same correlation matrix.
[2259]	1734	ALLOCATE( rand_it(nzb-mergp:nzt+1+mergp,-mergp:ny+mergp) )
[4309]	1735	rand_it = 0.0_wp
[2259]	1736
	1737	rand_av = 0.0_wp
	1738	rand_sigma_inv = 0.0_wp
	1739	nyz_inv = 1.0_wp / REAL( ( nzt+1 - nzb+1 ) * ( ny+1 ), KIND=wp )
[4309]	1740	!
	1741	!-- Compute and normalize random numbers only on left-boundary ranks.
	1742	IF ( myidx == id_stg_left ) THEN
	1743	!
	1744	!-- Allocate array for local set of random numbers
	1745	ALLOCATE( rand_it_l(nzb:nzt+1,nys:nyn) )
	1746	rand_it_l = 0.0_wp
[2259]	1747
[4309]	1748	i = nxl
	1749	DO j = nys, nyn
	1750	!
	1751	!-- Put the random seeds at grid point j,i
	1752	CALL random_seed_parallel( put=seq_random_array(:, j, i) )
	1753	DO k = nzb, nzt+1
	1754	CALL random_number_parallel( random_dummy )
	1755	rand_it_l(k,j) = random_dummy
	1756	rand_av = rand_av + rand_it_l(k,j)
	1757	ENDDO
	1758	!
	1759	!-- Get the new random seeds from last call at grid point j,i
	1760	CALL random_seed_parallel( get=seq_random_array(:, j, i) )
[2259]	1761	ENDDO
[4309]	1762	#if defined( __parallel )
	1763	!
	1764	!-- Sum-up the local averages of the random numbers
	1765	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_av, 1, MPI_REAL, &
	1766	MPI_SUM, comm1dy, ierr )
	1767	#endif
	1768	rand_av = rand_av * nyz_inv
	1769	!
	1770	!-- Obtain zero mean
	1771	rand_it_l = rand_it_l - rand_av
	1772	!
	1773	!-- Now, compute the variance
	1774	DO j = nys, nyn
	1775	DO k = nzb, nzt+1
	1776	rand_sigma_inv = rand_sigma_inv + rand_it_l(k,j)**2
	1777	ENDDO
[2259]	1778	ENDDO
	1779
[4309]	1780	#if defined( __parallel )
[2259]	1781	!
[4309]	1782	!-- Sum-up the local quadratic averages of the random numbers
	1783	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_sigma_inv, 1, MPI_REAL, &
	1784	MPI_SUM, comm1dy, ierr )
	1785	#endif
	1786	!
	1787	!-- Compute standard deviation
	1788	IF ( rand_sigma_inv /= 0.0_wp ) THEN
	1789	rand_sigma_inv = 1.0_wp / SQRT( rand_sigma_inv * nyz_inv )
	1790	ELSE
	1791	rand_sigma_inv = 1.0_wp
	1792	ENDIF
	1793	!
	1794	!-- Normalize with standard deviation to obtain unit variance
	1795	rand_it_l = rand_it_l * rand_sigma_inv
	1796	!
	1797	!-- Copy local random numbers on the global array
	1798	rand_it(nzb:nzt+1,nys:nyn) = rand_it_l(nzb:nzt+1,nys:nyn)
	1799	!
	1800	!-- Deallocate local array
	1801	DEALLOCATE( rand_it_l )
	1802	!
	1803	!-- Now, distribute the final set of random numbers to all mpi ranks located
	1804	!-- on the left boundary. Here, an allreduce with sum reduction is sufficient,
	1805	!-- or, in the non-parallel case, nothing need to be done at all.
	1806	#if defined( __parallel )
	1807	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_it, SIZE( rand_it ), MPI_REAL, &
	1808	MPI_SUM, comm1dy, ierr )
	1809	#endif
	1810	ENDIF
	1811	!
	1812	!-- Finally, distribute the set of random numbers (defined on the leftmost-
	1813	!-- located mpi ranks) to all other mpi ranks. Here, a allreduce with sum
	1814	!-- option is sufficient, because rand_it is zero on all other mpi_ranks.
	1815	!-- Note, the reduce operation is only performed with communicator comm1dx,
	1816	!-- where only 1 rank within the communicator has non-zero random numbers.
	1817	#if defined( __parallel )
	1818	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_it, SIZE( rand_it ), MPI_REAL, &
	1819	MPI_SUM, comm1dx, ierr )
	1820	#endif
	1821	!
	1822	!-- Periodic fill of random numbers in space
[2259]	1823	DO j = 0, ny
	1824	DO k = 1, mergp
	1825	rand_it(nzb -k,j) = rand_it(nzt+2-k,j) ! bottom margin
	1826	rand_it(nzt+1+k,j) = rand_it(nzb+k-1,j) ! top margin
	1827	ENDDO
	1828	ENDDO
	1829	DO j = 1, mergp
	1830	DO k = nzb-mergp, nzt+1+mergp
	1831	rand_it(k, -j) = rand_it(k,ny-j+1) ! south margin
	1832	rand_it(k,ny+j) = rand_it(k, j-1) ! north margin
	1833	ENDDO
	1834	ENDDO
	1835
	1836	!
	1837	!-- Generate velocity seed following Eq.6 of Xie and Castro (2008)
	1838	n_y2 = n_y * 2
	1839	n_z2 = n_z * 2
	1840	f_n_l = 0.0_wp
	1841
	1842	DO j = nysg, nyng
[2938]	1843	DO k = nzb_x_stg, nzt_x_stg+1
[2259]	1844	DO jj = -n_y2(k), n_y2(k)
	1845	DO kk = -n_z2(k), n_z2(k)
	1846	f_n_l(k,j) = f_n_l(k,j) &
	1847	+ b_y(jj,k) * b_z(kk,k) * rand_it(k+kk,j+jj)
	1848	ENDDO
	1849	ENDDO
	1850	ENDDO
	1851	ENDDO
	1852
	1853	DEALLOCATE( rand_it )
	1854	!
	1855	!-- Gather velocity seeds of full subdomain
[2938]	1856	send_count = nzt_x_stg - nzb_x_stg + 1
	1857	IF ( nzt_x_stg == nzt ) send_count = send_count + 1
[2259]	1858
	1859	#if defined( __parallel )
[4309]	1860	!
	1861	!-- Gather the velocity seed matrix on left boundary mpi ranks.
	1862	CALL MPI_GATHERV( f_n_l(nzb_x_stg,nysg), send_count, stg_type_yz_small, &
	1863	f_n(nzb+1,nysg), recv_count_yz, displs_yz, stg_type_yz, &
	1864	id_left, comm1dx, ierr )
	1865	!
	1866	!-- If required, gather the same velocity seed matrix on right boundary
	1867	!-- mpi ranks (in offline nesting for example).
	1868	IF ( PRESENT( id_right ) ) THEN
	1869	CALL MPI_GATHERV( f_n_l(nzb_x_stg,nysg), send_count, stg_type_yz_small, &
	1870	f_n(nzb+1,nysg), recv_count_yz, displs_yz, stg_type_yz,&
	1871	id_right, comm1dx, ierr )
	1872	ENDIF
[2259]	1873	#else
[2938]	1874	f_n(nzb+1:nzt+1,nysg:nyng) = f_n_l(nzb_x_stg:nzt_x_stg+1,nysg:nyng)
[2259]	1875	#endif
	1876
	1877
	1878	END SUBROUTINE stg_generate_seed_yz
	1879
[2938]	1880
	1881	!------------------------------------------------------------------------------!
	1882	! Description:
	1883	! ------------
	1884	!> Generate a set of random number rand_it wich is equal on each PE
	1885	!> and calculate the velocity seed f_n.
	1886	!> f_n is splitted in vertical direction by the number of PEs in y-direction and
	1887	!> and each PE calculates a vertical subsection of f_n. At the the end, all
	1888	!> parts are collected to form the full array.
	1889	!------------------------------------------------------------------------------!
[4309]	1890	SUBROUTINE stg_generate_seed_xz( n_x, n_z, b_x, b_z, f_n, id_south, id_north )
[2938]	1891
	1892	IMPLICIT NONE
	1893
	1894	INTEGER(iwp) :: i !< loop index in x-direction
[4309]	1895	INTEGER(iwp) :: id_north !< core ids at respective boundaries
	1896	INTEGER(iwp) :: id_south !< core ids at respective boundaries
[2938]	1897	INTEGER(iwp) :: ii !< loop index in x-direction
[4309]	1898	INTEGER(iwp) :: j !< grid index y-direction
[2938]	1899	INTEGER(iwp) :: k !< loop index in z-direction
	1900	INTEGER(iwp) :: kk !< loop index in z-direction
	1901	INTEGER(iwp) :: send_count !< send count for MPI_GATHERV
	1902
	1903	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_x !< length scale in x-direction
	1904	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_z !< length scale in z-direction
[3347]	1905	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_x2 !< n_x*2
[2938]	1906	INTEGER(iwp), DIMENSION(nzb:nzt+1) :: n_z2 !< n_z*2
	1907
	1908	REAL(wp) :: nxz_inv !< inverse of number of grid points in xz-slice
	1909	REAL(wp) :: rand_av !< average of random number
	1910	REAL(wp) :: rand_sigma_inv !< inverse of stdev of random number
	1911
[3347]	1912	REAL(wp), DIMENSION(-merg:merg,nzb:nzt+1) :: b_x !< filter function in x-direction
	1913	REAL(wp), DIMENSION(-merg:merg,nzb:nzt+1) :: b_z !< filter function in z-direction
[4309]	1914
[2938]	1915	REAL(wp), DIMENSION(nzb_y_stg:nzt_y_stg+1,nxlg:nxrg) :: f_n_l !< local velocity seed
[4309]	1916	REAL(wp), DIMENSION(nzb:nzt+1,nxlg:nxrg) :: f_n !< velocity seed
[2938]	1917
[4309]	1918	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rand_it !< global array of random numbers
	1919	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rand_it_l !< local array of random numbers
[2938]	1920
	1921	!
[4309]	1922	!-- Generate random numbers using the parallel random generator.
[2938]	1923	!-- The set of random numbers are modified to have an average of 0 and
[4309]	1924	!-- unit variance. Note, at the end the random number array must be defined
	1925	!-- globally in order to compute the correlation matrices. However,
	1926	!-- the calculation and normalization of random numbers is done locally,
	1927	!-- while the result is later distributed to all processes. Further,
	1928	!-- please note, a set of random numbers is only calculated for the
	1929	!-- left boundary, while the right boundary uses the same random numbers
	1930	!-- and thus also computes the same correlation matrix.
[2938]	1931	ALLOCATE( rand_it(nzb-mergp:nzt+1+mergp,-mergp:nx+mergp) )
[4309]	1932	rand_it = 0.0_wp
[2938]	1933
	1934	rand_av = 0.0_wp
	1935	rand_sigma_inv = 0.0_wp
	1936	nxz_inv = 1.0_wp / REAL( ( nzt+1 - nzb+1 ) * ( nx+1 ), KIND=wp )
[4309]	1937	!
	1938	!-- Compute and normalize random numbers only on south-boundary ranks.
	1939	IF ( myidy == id_stg_south ) THEN
	1940	!
	1941	!-- Allocate array for local set of random numbers
	1942	ALLOCATE( rand_it_l(nzb:nzt+1,nxl:nxr) )
	1943	rand_it_l = 0.0_wp
[2938]	1944
[4309]	1945	j = nys
	1946	DO i = nxl, nxr
	1947	!
	1948	!-- Put the random seeds at grid point j,i
	1949	CALL random_seed_parallel( put=seq_random_array(:, j, i) )
	1950	DO k = nzb, nzt+1
	1951	CALL random_number_parallel( random_dummy )
	1952	rand_it_l(k,i) = random_dummy
	1953	rand_av = rand_av + rand_it_l(k,i)
	1954	ENDDO
	1955	!
	1956	!-- Get the new random seeds from last call at grid point j,i
	1957	CALL random_seed_parallel( get=seq_random_array(:, j, i) )
[2938]	1958	ENDDO
[4309]	1959	#if defined( __parallel )
	1960	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_av, 1, MPI_REAL, &
	1961	MPI_SUM, comm1dx, ierr )
	1962	#endif
	1963	rand_av = rand_av * nxz_inv
	1964	!
	1965	!-- Obtain zero mean
	1966	rand_it_l = rand_it_l - rand_av
	1967	!
	1968	!-- Now, compute the variance
	1969	DO i = nxl, nxr
	1970	DO k = nzb, nzt+1
	1971	rand_sigma_inv = rand_sigma_inv + rand_it_l(k,i)**2
	1972	ENDDO
[2938]	1973	ENDDO
	1974
[4309]	1975	#if defined( __parallel )
	1976	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_sigma_inv, 1, MPI_REAL, &
	1977	MPI_SUM, comm1dx, ierr )
	1978	#endif
[2938]	1979	!
[4309]	1980	!-- Compute standard deviation
	1981	IF ( rand_sigma_inv /= 0.0_wp ) THEN
	1982	rand_sigma_inv = 1.0_wp / SQRT( rand_sigma_inv * nxz_inv )
	1983	ELSE
	1984	rand_sigma_inv = 1.0_wp
	1985	ENDIF
	1986	!
	1987	!-- Normalize with standard deviation to obtain unit variance
	1988	rand_it_l = rand_it_l * rand_sigma_inv
	1989	!
	1990	!-- Copy local random numbers on the global array
	1991	rand_it(nzb:nzt+1,nxl:nxr) = rand_it_l(nzb:nzt+1,nxl:nxr)
	1992	!
	1993	!-- Deallocate local array
	1994	DEALLOCATE( rand_it_l )
	1995	!
	1996	!-- Now, distribute the final set of random numbers to all mpi ranks located
	1997	!-- on the south boundary. Here, an allreduce with sum reduction is sufficient.
	1998	#if defined( __parallel )
	1999	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_it, SIZE( rand_it ), MPI_REAL, &
	2000	MPI_SUM, comm1dx, ierr )
	2001	#endif
	2002	ENDIF
	2003	!
	2004	!-- Finally, distribute the set of random numbers (defined on the
	2005	!-- southmost-located mpi ranks) to all other mpi ranks. Here, a allreduce
	2006	!-- with sum option is sufficient, because rand_it is zero on all other
	2007	!-- mpi_ranks. Note, the reduce operation is only performed with communicator
	2008	!-- comm1dy, where only 1 rank within the communicator has non zero random numbers.
	2009	#if defined( __parallel )
	2010	CALL MPI_ALLREDUCE( MPI_IN_PLACE, rand_it, SIZE( rand_it ), MPI_REAL, &
	2011	MPI_SUM, comm1dy, ierr )
	2012	#endif
	2013	!
[2938]	2014	!-- Periodic fill of random number in space
	2015	DO i = 0, nx
	2016	DO k = 1, mergp
	2017	rand_it(nzb-k,i) = rand_it(nzt+2-k,i) ! bottom margin
	2018	rand_it(nzt+1+k,i) = rand_it(nzb+k-1,i) ! top margin
	2019	ENDDO
	2020	ENDDO
	2021	DO i = 1, mergp
	2022	DO k = nzb-mergp, nzt+1+mergp
	2023	rand_it(k,-i) = rand_it(k,nx-i+1) ! left margin
	2024	rand_it(k,nx+i) = rand_it(k,i-1) ! right margin
	2025	ENDDO
	2026	ENDDO
	2027	!
	2028	!-- Generate velocity seed following Eq.6 of Xie and Castro (2008)
	2029	n_x2 = n_x * 2
	2030	n_z2 = n_z * 2
	2031	f_n_l = 0.0_wp
	2032
	2033	DO i = nxlg, nxrg
	2034	DO k = nzb_y_stg, nzt_y_stg+1
	2035	DO ii = -n_x2(k), n_x2(k)
	2036	DO kk = -n_z2(k), n_z2(k)
	2037	f_n_l(k,i) = f_n_l(k,i) &
	2038	+ b_x(ii,k) * b_z(kk,k) * rand_it(k+kk,i+ii)
	2039	ENDDO
	2040	ENDDO
	2041	ENDDO
	2042	ENDDO
	2043
	2044	DEALLOCATE( rand_it )
	2045
	2046	!
	2047	!-- Gather velocity seeds of full subdomain
	2048	send_count = nzt_y_stg - nzb_y_stg + 1
	2049	IF ( nzt_y_stg == nzt ) send_count = send_count + 1
	2050
	2051	#if defined( __parallel )
[4309]	2052	!
	2053	!-- Gather the processed velocity seed on south boundary mpi ranks.
	2054	CALL MPI_GATHERV( f_n_l(nzb_y_stg,nxlg), send_count, stg_type_xz_small, &
	2055	f_n(nzb+1,nxlg), recv_count_xz, displs_xz, stg_type_xz, &
	2056	id_south, comm1dy, ierr )
	2057	!
	2058	!-- Gather the processed velocity seed on north boundary mpi ranks.
	2059	CALL MPI_GATHERV( f_n_l(nzb_y_stg,nxlg), send_count, stg_type_xz_small, &
	2060	f_n(nzb+1,nxlg), recv_count_xz, displs_xz, stg_type_xz, &
	2061	id_north, comm1dy, ierr )
[2938]	2062	#else
	2063	f_n(nzb+1:nzt+1,nxlg:nxrg) = f_n_l(nzb_y_stg:nzt_y_stg+1,nxlg:nxrg)
	2064	#endif
	2065
	2066	END SUBROUTINE stg_generate_seed_xz
	2067
[3347]	2068	!------------------------------------------------------------------------------!
	2069	! Description:
	2070	! ------------
	2071	!> Parametrization of the Reynolds stress tensor, following the parametrization
	2072	!> described in Rotach et al. (1996), which is applied in state-of-the-art
	2073	!> dispserion modelling. Please note, the parametrization does not distinguish
	2074	!> between along-wind and cross-wind turbulence.
	2075	!------------------------------------------------------------------------------!
	2076	SUBROUTINE parametrize_reynolds_stress
	2077
	2078	IMPLICIT NONE
	2079
	2080	INTEGER(iwp) :: k !< loop index in z-direction
	2081
	2082	REAL(wp) :: zzi !< ratio of z/zi
	2083
	2084	DO k = nzb+1, nzt+1
	2085	!
[4022]	2086	!-- Calculate function to gradually decrease Reynolds stress above ABL top.
	2087	!-- The function decreases to 1/10 after one length scale above the
	2088	!-- ABL top.
	2089	blend = MIN( 1.0_wp, EXP( d_l * zu(k) - d_l * zi_ribulk ) )
[3347]	2090	!
[4022]	2091	!-- Determine normalized height coordinate
	2092	zzi = zu(k) / zi_ribulk
[3347]	2093	!
[4022]	2094	!-- u'u' and v'v'. Assume isotropy. Note, add a small negative number
	2095	!-- to the denominator, else the merge-function can crash if scale_l is
	2096	!-- zero.
	2097	r11(k) = scale_us*2 ( &
	2098	MERGE( 0.35_wp * ABS( &
	2099	- zi_ribulk / ( kappa * scale_l - 10E-4_wp ) &
	2100	)**( 2.0_wp / 3.0_wp ), &
	2101	0.0_wp, &
	2102	scale_l < 0.0_wp ) &
	2103	+ 5.0_wp - 4.0_wp * zzi &
	2104	) * blend
	2105
	2106	r22(k) = r11(k)
	2107	!
	2108	!-- w'w'
	2109	r33(k) = scale_wm*2 ( &
	2110	1.5_wp * zzi*( 2.0_wp / 3.0_wp ) EXP( -2.0_wp * zzi ) &
	2111	+ ( 1.7_wp - zzi ) * ( scale_us / scale_wm )**2 &
	2112	) * blend
	2113	!
	2114	!-- u'w' and v'w'. Assume isotropy.
	2115	r31(k) = - scale_us*2 ( 1.01_wp - MIN( zzi, 1.0_wp ) ) * blend
	2116	r32(k) = r31(k)
[3347]	2117	!
[4022]	2118	!-- For u'v' no parametrization exist so far - ?. For simplicity assume
	2119	!-- a similar profile as for u'w'.
	2120	r21(k) = r31(k)
[3347]	2121	ENDDO
	2122
	2123	!
	2124	!-- Set bottom boundary condition
	2125	r11(nzb) = r11(nzb+1)
	2126	r22(nzb) = r22(nzb+1)
	2127	r33(nzb) = r33(nzb+1)
	2128
	2129	r21(nzb) = r11(nzb+1)
	2130	r31(nzb) = r31(nzb+1)
	2131	r32(nzb) = r32(nzb+1)
	2132
	2133
	2134	END SUBROUTINE parametrize_reynolds_stress
	2135
	2136	!------------------------------------------------------------------------------!
	2137	! Description:
	2138	! ------------
	2139	!> Calculate the coefficient matrix from the Lund rotation.
	2140	!------------------------------------------------------------------------------!
	2141	SUBROUTINE calc_coeff_matrix
	2142
	2143	IMPLICIT NONE
	2144
	2145	INTEGER(iwp) :: k !< loop index in z-direction
	2146
	2147	!
	2148	!-- Calculate coefficient matrix. Split loops to allow for loop vectorization.
	2149	DO k = nzb+1, nzt+1
[4022]	2150	IF ( r11(k) > 10E-6_wp ) THEN
[3347]	2151	a11(k) = SQRT( r11(k) )
	2152	a21(k) = r21(k) / a11(k)
	2153	a31(k) = r31(k) / a11(k)
	2154	ELSE
	2155	a11(k) = 10E-8_wp
	2156	a21(k) = 10E-8_wp
	2157	a31(k) = 10E-8_wp
	2158	ENDIF
	2159	ENDDO
	2160	DO k = nzb+1, nzt+1
	2161	a22(k) = r22(k) - a21(k)**2
[4022]	2162	IF ( a22(k) > 10E-6_wp ) THEN
[3347]	2163	a22(k) = SQRT( a22(k) )
	2164	a32(k) = r32(k) - a21(k) * a31(k) / a22(k)
	2165	ELSE
	2166	a22(k) = 10E-8_wp
	2167	a32(k) = 10E-8_wp
	2168	ENDIF
	2169	ENDDO
	2170	DO k = nzb+1, nzt+1
	2171	a33(k) = r33(k) - a31(k)2 - a32(k)2
[4022]	2172	IF ( a33(k) > 10E-6_wp ) THEN
[3347]	2173	a33(k) = SQRT( a33(k) )
	2174	ELSE
	2175	a33(k) = 10E-8_wp
	2176	ENDIF
	2177	ENDDO
	2178	!
	2179	!-- Set bottom boundary condition
	2180	a11(nzb) = a11(nzb+1)
	2181	a22(nzb) = a22(nzb+1)
	2182	a21(nzb) = a21(nzb+1)
	2183	a33(nzb) = a33(nzb+1)
	2184	a31(nzb) = a31(nzb+1)
	2185	a32(nzb) = a32(nzb+1)
	2186
	2187	END SUBROUTINE calc_coeff_matrix
	2188
	2189	!------------------------------------------------------------------------------!
	2190	! Description:
	2191	! ------------
	2192	!> This routine controls the re-adjustment of the turbulence statistics used
	2193	!> for generating turbulence at the lateral boundaries.
	2194	!------------------------------------------------------------------------------!
	2195	SUBROUTINE stg_adjust
	2196
	2197	IMPLICIT NONE
	2198
[3987]	2199
	2200	IF ( debug_output_timestep ) CALL debug_message( 'stg_adjust', 'start' )
[3347]	2201	!
[4022]	2202	!-- In case of dirichlet inflow boundary conditions only at one lateral
	2203	!-- boundary, i.e. in the case no offline or self nesting is applied but
	2204	!-- synthetic turbulence shall be parametrized nevertheless, the
	2205	!-- boundary-layer depth need to determined first.
	2206	IF ( .NOT. nesting_offline .AND. .NOT. child_domain ) &
	2207	CALL nesting_offl_calc_zi
	2208	!
	2209	!-- Compute scaling parameters (domain-averaged), such as friction velocity
	2210	!-- are calculated.
[3347]	2211	CALL calc_scaling_variables
	2212	!
	2213	!-- Set length and time scales depending on boundary-layer height
	2214	CALL calc_length_and_time_scale
	2215	!
	2216	!-- Parametrize Reynolds-stress tensor, diagonal elements as well
	2217	!-- as r21 (v'u'), r31 (w'u'), r32 (w'v'). Parametrization follows
	2218	!-- Rotach et al. (1996) and is based on boundary-layer depth,
	2219	!-- friction velocity and velocity scale.
	2220	CALL parametrize_reynolds_stress
	2221	!
	2222	!-- Calculate coefficient matrix from Reynolds stress tensor
	2223	!-- (Lund rotation)
	2224	CALL calc_coeff_matrix
	2225	!
	2226	!-- Determine filter functions on basis of updated length scales
	2227	CALL stg_filter_func( nux, bux ) !filter ux
	2228	CALL stg_filter_func( nuy, buy ) !filter uy
	2229	CALL stg_filter_func( nuz, buz ) !filter uz
	2230	CALL stg_filter_func( nvx, bvx ) !filter vx
	2231	CALL stg_filter_func( nvy, bvy ) !filter vy
	2232	CALL stg_filter_func( nvz, bvz ) !filter vz
	2233	CALL stg_filter_func( nwx, bwx ) !filter wx
	2234	CALL stg_filter_func( nwy, bwy ) !filter wy
	2235	CALL stg_filter_func( nwz, bwz ) !filter wz
	2236	!
	2237	!-- Reset time counter for controlling next adjustment to zero
	2238	time_stg_adjust = 0.0_wp
[3987]	2239
	2240	IF ( debug_output_timestep ) CALL debug_message( 'stg_adjust', 'end' )
[3347]	2241
	2242	END SUBROUTINE stg_adjust
	2243
	2244
	2245	!------------------------------------------------------------------------------!
	2246	! Description:
	2247	! ------------
	2248	!> Calculates turbuluent length and time scales if these are not available
	2249	!> from measurements.
	2250	!------------------------------------------------------------------------------!
	2251	SUBROUTINE calc_length_and_time_scale
	2252
	2253	IMPLICIT NONE
	2254
	2255
[4022]	2256	INTEGER(iwp) :: k !< loop index in z-direction
[3347]	2257
[4022]	2258	REAL(wp) :: length_scale_dum !< effectively used length scale
	2259
[3347]	2260	!
	2261	!-- In initial call the boundary-layer depth can be zero. This case, set
	2262	!-- minimum value for boundary-layer depth, to setup length scales correctly.
	2263	zi_ribulk = MAX( zi_ribulk, zw(nzb+2) )
	2264	!
	2265	!-- Set-up default turbulent length scales. From the numerical point of
	2266	!-- view the imposed perturbations should not be immediately dissipated
	2267	!-- by the numerics. The numerical dissipation, however, acts on scales
	2268	!-- up to 8 x the grid spacing. For this reason, set the turbulence
	2269	!-- length scale to 8 time the grid spacing. Further, above the boundary
	2270	!-- layer height, set turbulence lenght scales to zero (equivalent to not
	2271	!-- imposing any perturbations) in order to save computational costs.
	2272	!-- Typical time scales are derived by assuming Taylors's hypothesis,
	2273	!-- using the length scales and the mean profiles of u- and v-component.
	2274	DO k = nzb+1, nzt+1
	2275	!
[4022]	2276	!-- Determine blending parameter. Within the boundary layer length scales
	2277	!-- are constant, while above lengths scales approach gradully zero,
	2278	!-- i.e. imposed turbulence is not correlated in space and time,
	2279	!-- just white noise, which saves computations power as the loops for the
	2280	!-- computation of the filter functions depend on the length scales.
	2281	!-- The value decreases to 1/10 after one length scale above the
	2282	!-- ABL top.
	2283	blend = MIN( 1.0_wp, EXP( d_l * zu(k) - d_l * zi_ribulk ) )
[3347]	2284	!
[4022]	2285	!-- Assume isotropic turbulence length scales
	2286	nux(k) = MAX( INT( length_scale * ddx ), 1 ) * blend
	2287	nuy(k) = MAX( INT( length_scale * ddy ), 1 ) * blend
	2288	nvx(k) = MAX( INT( length_scale * ddx ), 1 ) * blend
	2289	nvy(k) = MAX( INT( length_scale * ddy ), 1 ) * blend
	2290	nwx(k) = MAX( INT( length_scale * ddx ), 1 ) * blend
	2291	nwy(k) = MAX( INT( length_scale * ddy ), 1 ) * blend
[3347]	2292	!
[4022]	2293	!-- Along the vertical direction limit the length scale further by the
	2294	!-- boundary-layer depth to assure that no length scales larger than
	2295	!-- the boundary-layer depth are used
	2296	length_scale_dum = MIN( length_scale, zi_ribulk )
	2297
	2298	nuz(k) = MAX( INT( length_scale_dum * ddzw(k) ), 1 ) * blend
	2299	nvz(k) = MAX( INT( length_scale_dum * ddzw(k) ), 1 ) * blend
	2300	nwz(k) = MAX( INT( length_scale_dum * ddzw(k) ), 1 ) * blend
[3347]	2301	!
[4022]	2302	!-- Limit time scales, else they become very larger for low wind speed,
	2303	!-- imposing long-living inflow perturbations which in turn propagate
	2304	!-- further into the model domain. Use u_init and v_init to calculate
	2305	!-- the time scales, which will be equal to the inflow profiles, both,
	2306	!-- in offline nesting mode or in dirichlet/radiation mode.
	2307	tu(k) = MIN( dt_stg_adjust, length_scale / &
	2308	( ABS( u_init(k) ) + 0.1_wp ) ) * blend
	2309	tv(k) = MIN( dt_stg_adjust, length_scale / &
	2310	( ABS( v_init(k) ) + 0.1_wp ) ) * blend
	2311	!
	2312	!-- Time scale of w-component is a mixture from u- and v-component.
	2313	tw(k) = SQRT( tu(k)2 + tv(k)2 ) * blend
	2314
[3347]	2315	ENDDO
	2316	!
	2317	!-- Set bottom boundary condition for the length and time scales
	2318	nux(nzb) = nux(nzb+1)
	2319	nuy(nzb) = nuy(nzb+1)
	2320	nuz(nzb) = nuz(nzb+1)
	2321	nvx(nzb) = nvx(nzb+1)
	2322	nvy(nzb) = nvy(nzb+1)
	2323	nvz(nzb) = nvz(nzb+1)
	2324	nwx(nzb) = nwx(nzb+1)
	2325	nwy(nzb) = nwy(nzb+1)
	2326	nwz(nzb) = nwz(nzb+1)
	2327
	2328	tu(nzb) = tu(nzb+1)
	2329	tv(nzb) = tv(nzb+1)
	2330	tw(nzb) = tw(nzb+1)
	2331
	2332
	2333	END SUBROUTINE calc_length_and_time_scale
	2334
	2335	!------------------------------------------------------------------------------!
	2336	! Description:
	2337	! ------------
	2338	!> Calculate scaling variables which are used for turbulence parametrization
	2339	!> according to Rotach et al. (1996). Scaling variables are: friction velocity,
	2340	!> boundary-layer depth, momentum velocity scale, and Obukhov length.
	2341	!------------------------------------------------------------------------------!
	2342	SUBROUTINE calc_scaling_variables
	2343
	2344	USE surface_mod, &
[4148]	2345	ONLY: surf_def_h, surf_lsm_h, surf_usm_h
[3347]	2346
	2347	IMPLICIT NONE
	2348
	2349	INTEGER(iwp) :: i !< loop index in x-direction
	2350	INTEGER(iwp) :: j !< loop index in y-direction
	2351	INTEGER(iwp) :: k !< loop index in z-direction
	2352	INTEGER(iwp) :: m !< surface element index
	2353
	2354	REAL(wp) :: friction_vel_l !< mean friction veloctiy on subdomain
[3937]	2355	REAL(wp) :: pt_surf_mean !< mean near surface temperature (at 1st grid point)
	2356	REAL(wp) :: pt_surf_mean_l !< mean near surface temperature (at 1st grid point) on subdomain
	2357	REAL(wp) :: scale_l_l !< mean Obukhov lenght on subdomain
[3347]	2358	REAL(wp) :: shf_mean !< mean surface sensible heat flux
	2359	REAL(wp) :: shf_mean_l !< mean surface sensible heat flux on subdomain
	2360	REAL(wp) :: w_convective !< convective velocity scale
	2361
	2362	!
[3937]	2363	!-- Calculate mean friction velocity, velocity scale, heat flux and
	2364	!-- near-surface temperature in the model domain.
	2365	pt_surf_mean_l = 0.0_wp
	2366	shf_mean_l = 0.0_wp
	2367	scale_l_l = 0.0_wp
	2368	friction_vel_l = 0.0_wp
[3347]	2369	DO m = 1, surf_def_h(0)%ns
[3937]	2370	i = surf_def_h(0)%i(m)
	2371	j = surf_def_h(0)%j(m)
	2372	k = surf_def_h(0)%k(m)
	2373	friction_vel_l = friction_vel_l + surf_def_h(0)%us(m)
	2374	shf_mean_l = shf_mean_l + surf_def_h(0)%shf(m) * drho_air(k)
	2375	scale_l_l = scale_l_l + surf_def_h(0)%ol(m)
	2376	pt_surf_mean_l = pt_surf_mean_l + pt(k,j,i)
[3347]	2377	ENDDO
	2378	DO m = 1, surf_lsm_h%ns
[3937]	2379	i = surf_lsm_h%i(m)
	2380	j = surf_lsm_h%j(m)
	2381	k = surf_lsm_h%k(m)
	2382	friction_vel_l = friction_vel_l + surf_lsm_h%us(m)
	2383	shf_mean_l = shf_mean_l + surf_lsm_h%shf(m) * drho_air(k)
	2384	scale_l_l = scale_l_l + surf_lsm_h%ol(m)
	2385	pt_surf_mean_l = pt_surf_mean_l + pt(k,j,i)
[3347]	2386	ENDDO
	2387	DO m = 1, surf_usm_h%ns
[3937]	2388	i = surf_usm_h%i(m)
	2389	j = surf_usm_h%j(m)
	2390	k = surf_usm_h%k(m)
	2391	friction_vel_l = friction_vel_l + surf_usm_h%us(m)
	2392	shf_mean_l = shf_mean_l + surf_usm_h%shf(m) * drho_air(k)
	2393	scale_l_l = scale_l_l + surf_usm_h%ol(m)
	2394	pt_surf_mean_l = pt_surf_mean_l + pt(k,j,i)
[3347]	2395	ENDDO
	2396
	2397	#if defined( __parallel )
[3937]	2398	CALL MPI_ALLREDUCE( friction_vel_l, scale_us, 1, MPI_REAL, MPI_SUM, &
[3347]	2399	comm2d, ierr )
[3937]	2400	CALL MPI_ALLREDUCE( shf_mean_l, shf_mean, 1, MPI_REAL, MPI_SUM, &
[3347]	2401	comm2d, ierr )
[3937]	2402	CALL MPI_ALLREDUCE( scale_l_l, scale_l, 1, MPI_REAL, MPI_SUM, &
	2403	comm2d, ierr )
	2404	CALL MPI_ALLREDUCE( pt_surf_mean_l, pt_surf_mean, 1, MPI_REAL, MPI_SUM, &
	2405	comm2d, ierr )
[3347]	2406	#else
[3937]	2407	scale_us = friction_vel_l
	2408	shf_mean = shf_mean_l
	2409	scale_l = scale_l_l
	2410	pt_surf_mean = pt_surf_mean_l
[3347]	2411	#endif
	2412
[3937]	2413	scale_us = scale_us / REAL( ( nx + 1 ) * ( ny + 1 ), KIND = wp )
	2414	shf_mean = shf_mean / REAL( ( nx + 1 ) * ( ny + 1 ), KIND = wp )
	2415	scale_l = scale_l / REAL( ( nx + 1 ) * ( ny + 1 ), KIND = wp )
	2416	pt_surf_mean = pt_surf_mean / REAL( ( nx + 1 ) * ( ny + 1 ), KIND = wp )
[3347]	2417	!
	2418	!-- Compute mean convective velocity scale. Note, in case the mean heat flux
	2419	!-- is negative, set convective velocity scale to zero.
	2420	IF ( shf_mean > 0.0_wp ) THEN
[3937]	2421	w_convective = ( g * shf_mean * zi_ribulk / pt_surf_mean )**( 1.0_wp / 3.0_wp )
[3347]	2422	ELSE
	2423	w_convective = 0.0_wp
	2424	ENDIF
	2425	!
	2426	!-- Finally, in order to consider also neutral or stable stratification,
	2427	!-- compute momentum velocity scale from u* and convective velocity scale,
	2428	!-- according to Rotach et al. (1996).
	2429	scale_wm = ( scale_us*3 + 0.6_wp w_convective3 )( 1.0_wp / 3.0_wp )
	2430
	2431	END SUBROUTINE calc_scaling_variables
	2432
[2259]	2433	END MODULE synthetic_turbulence_generator_mod

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