Home

Context Navigation

source: palm/trunk/SOURCE/plant_canopy_model.f90 @ 1708

Last change on this file since 1708 was 1683, checked in by knoop, 9 years ago
last commit documented
Property svn:keywords set to `Id`
File size: 40.8 KB

Rev	Line
[1682]	1	!> @file plant_canopy_model.f90
[1036]	2	!--------------------------------------------------------------------------------!
	3	! This file is part of PALM.
	4	!
	5	! PALM is free software: you can redistribute it and/or modify it under the terms
	6	! of the GNU General Public License as published by the Free Software Foundation,
	7	! either version 3 of the License, or (at your option) any later version.
	8	!
	9	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
	10	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
	11	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
	12	!
	13	! You should have received a copy of the GNU General Public License along with
	14	! PALM. If not, see <http://www.gnu.org/licenses/>.
	15	!
[1310]	16	! Copyright 1997-2014 Leibniz Universitaet Hannover
[1036]	17	!--------------------------------------------------------------------------------!
	18	!
[257]	19	! Current revisions:
[138]	20	! -----------------
[1485]	21	!
[1683]	22	!
[1485]	23	! Former revisions:
	24	! -----------------
	25	! $Id: plant_canopy_model.f90 1683 2015-10-07 23:57:51Z maronga $
	26	!
[1683]	27	! 1682 2015-10-07 23:56:08Z knoop
	28	! Code annotations made doxygen readable
	29	!
[1485]	30	! 1484 2014-10-21 10:53:05Z kanani
[1484]	31	! Changes due to new module structure of the plant canopy model:
	32	! module plant_canopy_model_mod now contains a subroutine for the
	33	! initialization of the canopy model (init_plant_canopy),
	34	! limitation of the canopy drag (previously accounted for by calculation of
	35	! a limiting canopy timestep for the determination of the maximum LES timestep
	36	! in subroutine timestep) is now realized by the calculation of pre-tendencies
	37	! and preliminary velocities in subroutine plant_canopy_model,
	38	! some redundant MPI communication removed in subroutine init_plant_canopy
	39	! (was previously in init_3d_model),
	40	! unnecessary 3d-arrays lad_u, lad_v, lad_w removed - lad information on the
	41	! respective grid is now provided only by lad_s (e.g. in the calculation of
	42	! the tendency terms or of cum_lai_hf),
	43	! drag_coefficient, lai, leaf_surface_concentration,
	44	! scalar_exchange_coefficient, sec and sls renamed to canopy_drag_coeff,
	45	! cum_lai_hf, leaf_surface_conc, leaf_scalar_exch_coeff, lsec and lsc,
	46	! respectively,
	47	! unnecessary 3d-arrays cdc, lsc and lsec now defined as single-value constants,
	48	! USE-statements and ONLY-lists modified accordingly
[1341]	49	!
	50	! 1340 2014-03-25 19:45:13Z kanani
	51	! REAL constants defined as wp-kind
	52	!
[1321]	53	! 1320 2014-03-20 08:40:49Z raasch
[1320]	54	! ONLY-attribute added to USE-statements,
	55	! kind-parameters added to all INTEGER and REAL declaration statements,
	56	! kinds are defined in new module kinds,
	57	! old module precision_kind is removed,
	58	! revision history before 2012 removed,
	59	! comment fields (!:) to be used for variable explanations added to
	60	! all variable declaration statements
[153]	61	!
[1037]	62	! 1036 2012-10-22 13:43:42Z raasch
	63	! code put under GPL (PALM 3.9)
	64	!
[139]	65	! 138 2007-11-28 10:03:58Z letzel
	66	! Initial revision
	67	!
[138]	68	! Description:
	69	! ------------
[1682]	70	!> 1) Initialization of the canopy model, e.g. construction of leaf area density
	71	!> profile (subroutine init_plant_canopy).
	72	!> 2) Calculation of sinks and sources of momentum, heat and scalar concentration
	73	!> due to canopy elements (subroutine plant_canopy_model).
[138]	74	!------------------------------------------------------------------------------!
[1682]	75	MODULE plant_canopy_model_mod
	76
[1484]	77	USE arrays_3d, &
	78	ONLY: dzu, dzw, e, q, shf, tend, u, v, w, zu, zw
[138]	79
[1484]	80	USE indices, &
	81	ONLY: nbgp, nxl, nxlg, nxlu, nxr, nxrg, nyn, nyng, nys, nysg, nysv, &
	82	nz, nzb, nzb_s_inner, nzb_u_inner, nzb_v_inner, nzb_w_inner, nzt
	83
	84	USE kinds
	85
	86
	87	IMPLICIT NONE
	88
	89
[1682]	90	CHARACTER (LEN=20) :: canopy_mode = 'block' !< canopy coverage
[1484]	91
[1682]	92	INTEGER(iwp) :: pch_index = 0 !< plant canopy height/top index
[1484]	93	INTEGER(iwp) :: &
[1682]	94	lad_vertical_gradient_level_ind(10) = -9999 !< lad-profile levels (index)
[1484]	95
[1682]	96	LOGICAL :: calc_beta_lad_profile = .FALSE. !< switch for calc. of lad from beta func.
	97	LOGICAL :: plant_canopy = .FALSE. !< switch for use of canopy model
[1484]	98
[1682]	99	REAL(wp) :: alpha_lad = 9999999.9_wp !< coefficient for lad calculation
	100	REAL(wp) :: beta_lad = 9999999.9_wp !< coefficient for lad calculation
	101	REAL(wp) :: canopy_drag_coeff = 0.0_wp !< canopy drag coefficient (parameter)
	102	REAL(wp) :: cdc = 0.0_wp !< canopy drag coeff. (abbreviation used in equations)
	103	REAL(wp) :: cthf = 0.0_wp !< canopy top heat flux
	104	REAL(wp) :: dt_plant_canopy = 0.0_wp !< timestep account. for canopy drag
	105	REAL(wp) :: lad_surface = 0.0_wp !< lad surface value
	106	REAL(wp) :: lai_beta = 0.0_wp !< leaf area index (lai) for lad calc.
[1484]	107	REAL(wp) :: &
[1682]	108	leaf_scalar_exch_coeff = 0.0_wp !< canopy scalar exchange coeff.
[1484]	109	REAL(wp) :: &
[1682]	110	leaf_surface_conc = 0.0_wp !< leaf surface concentration
	111	REAL(wp) :: lsec = 0.0_wp !< leaf scalar exchange coeff.
	112	REAL(wp) :: lsc = 0.0_wp !< leaf surface concentration
[1484]	113
	114	REAL(wp) :: &
[1682]	115	lad_vertical_gradient(10) = 0.0_wp !< lad gradient
[1484]	116	REAL(wp) :: &
[1682]	117	lad_vertical_gradient_level(10) = -9999999.9_wp !< lad-prof. levels (in m)
[1484]	118
[1682]	119	REAL(wp), DIMENSION(:), ALLOCATABLE :: lad !< leaf area density
	120	REAL(wp), DIMENSION(:), ALLOCATABLE :: pre_lad !< preliminary lad
[1484]	121
	122	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: &
[1682]	123	canopy_heat_flux !< canopy heat flux
	124	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: cum_lai_hf !< cumulative lai for heatflux calc.
	125	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: lad_s !< lad on scalar-grid
[1484]	126
	127
	128	SAVE
	129
	130
[138]	131	PRIVATE
[1484]	132	PUBLIC alpha_lad, beta_lad, calc_beta_lad_profile, canopy_drag_coeff, &
	133	canopy_mode, cdc, cthf, dt_plant_canopy, init_plant_canopy, lad, &
	134	lad_s, lad_surface, lad_vertical_gradient, &
	135	lad_vertical_gradient_level, lad_vertical_gradient_level_ind, &
	136	lai_beta, leaf_scalar_exch_coeff, leaf_surface_conc, lsc, lsec, &
	137	pch_index, plant_canopy, plant_canopy_model
[138]	138
[1484]	139
	140	INTERFACE init_plant_canopy
	141	MODULE PROCEDURE init_plant_canopy
	142	END INTERFACE init_plant_canopy
	143
[138]	144	INTERFACE plant_canopy_model
	145	MODULE PROCEDURE plant_canopy_model
	146	MODULE PROCEDURE plant_canopy_model_ij
	147	END INTERFACE plant_canopy_model
	148
[1484]	149
	150
	151
[138]	152	CONTAINS
	153
	154
	155	!------------------------------------------------------------------------------!
[1484]	156	! Description:
	157	! ------------
[1682]	158	!> Initialization of the plant canopy model
[138]	159	!------------------------------------------------------------------------------!
[1484]	160	SUBROUTINE init_plant_canopy
	161
	162
	163	USE control_parameters, &
	164	ONLY: dz, ocean, passive_scalar
	165
	166
	167	IMPLICIT NONE
	168
[1682]	169	INTEGER(iwp) :: i !< running index
	170	INTEGER(iwp) :: j !< running index
	171	INTEGER(iwp) :: k !< running index
[1484]	172
[1682]	173	REAL(wp) :: int_bpdf !< vertical integral for lad-profile construction
	174	REAL(wp) :: dzh !< vertical grid spacing in units of canopy height
	175	REAL(wp) :: gradient !< gradient for lad-profile construction
	176	REAL(wp) :: canopy_height !< canopy height for lad-profile construction
[1484]	177
	178	!
	179	!-- Allocate one-dimensional arrays for the computation of the
	180	!-- leaf area density (lad) profile
	181	ALLOCATE( lad(0:nz+1), pre_lad(0:nz+1) )
	182	lad = 0.0_wp
	183	pre_lad = 0.0_wp
	184
	185	!
	186	!-- Compute the profile of leaf area density used in the plant
	187	!-- canopy model. The profile can either be constructed from
	188	!-- prescribed vertical gradients of the leaf area density or by
	189	!-- using a beta probability density function (see e.g. Markkanen et al.,
	190	!-- 2003: Boundary-Layer Meteorology, 106, 437-459)
	191	IF ( .NOT. calc_beta_lad_profile ) THEN
	192
	193	!
	194	!-- Use vertical gradients for lad-profile construction
	195	i = 1
	196	gradient = 0.0_wp
	197
	198	IF ( .NOT. ocean ) THEN
	199
	200	lad(0) = lad_surface
	201	lad_vertical_gradient_level_ind(1) = 0
	202
	203	DO k = 1, pch_index
	204	IF ( i < 11 ) THEN
	205	IF ( lad_vertical_gradient_level(i) < zu(k) .AND. &
	206	lad_vertical_gradient_level(i) >= 0.0_wp ) THEN
	207	gradient = lad_vertical_gradient(i)
	208	lad_vertical_gradient_level_ind(i) = k - 1
	209	i = i + 1
	210	ENDIF
	211	ENDIF
	212	IF ( gradient /= 0.0_wp ) THEN
	213	IF ( k /= 1 ) THEN
	214	lad(k) = lad(k-1) + dzu(k) * gradient
	215	ELSE
	216	lad(k) = lad_surface + dzu(k) * gradient
	217	ENDIF
	218	ELSE
	219	lad(k) = lad(k-1)
	220	ENDIF
	221	ENDDO
	222
	223	ENDIF
	224
	225	!
	226	!-- In case of no given leaf area density gradients, choose a vanishing
	227	!-- gradient. This information is used for the HEADER and the RUN_CONTROL
	228	!-- file.
	229	IF ( lad_vertical_gradient_level(1) == -9999999.9_wp ) THEN
	230	lad_vertical_gradient_level(1) = 0.0_wp
	231	ENDIF
	232
	233	ELSE
	234
	235	!
	236	!-- Use beta function for lad-profile construction
	237	int_bpdf = 0.0_wp
	238	canopy_height = pch_index * dz
	239
	240	DO k = nzb, pch_index
	241	int_bpdf = int_bpdf + &
	242	( ( ( zw(k) / canopy_height )*( alpha_lad-1.0_wp ) ) &
	243	( ( 1.0_wp - ( zw(k) / canopy_height ) )*( beta_lad-1.0_wp ) ) &
	244	( ( zw(k+1)-zw(k) ) / canopy_height ) )
	245	ENDDO
	246
	247	!
	248	!-- Preliminary lad profile (defined on w-grid)
	249	DO k = nzb, pch_index
	250	pre_lad(k) = lai_beta * &
	251	( ( ( zw(k) / canopy_height )*( alpha_lad-1.0_wp ) ) &
	252	( ( 1.0_wp - ( zw(k) / canopy_height ) )**( beta_lad-1.0_wp ) ) / &
	253	int_bpdf &
	254	) / canopy_height
	255	ENDDO
	256
	257	!
	258	!-- Final lad profile (defined on scalar-grid level, since most prognostic
	259	!-- quantities are defined there, hence, less interpolation is required
	260	!-- when calculating the canopy tendencies)
	261	lad(0) = pre_lad(0)
	262	DO k = nzb+1, pch_index
	263	lad(k) = 0.5 * ( pre_lad(k-1) + pre_lad(k) )
	264	ENDDO
	265
	266	ENDIF
	267
	268	!
	269	!-- Allocate 3D-array for the leaf area density (lad_s). In case of a
	270	!-- prescribed canopy-top heat flux (cthf), allocate 3D-arrays for
	271	!-- the cumulative leaf area index (cum_lai_hf) and the canopy heat flux.
	272	ALLOCATE( lad_s(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	273
	274	IF ( cthf /= 0.0_wp ) THEN
	275	ALLOCATE( cum_lai_hf(nzb:nzt+1,nysg:nyng,nxlg:nxrg), &
	276	canopy_heat_flux(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
	277	ENDIF
	278
	279	!
	280	!-- Initialize canopy parameters cdc (canopy drag coefficient),
	281	!-- lsec (leaf scalar exchange coefficient), lsc (leaf surface concentration)
	282	!-- with the prescribed values
	283	cdc = canopy_drag_coeff
	284	lsec = leaf_scalar_exch_coeff
	285	lsc = leaf_surface_conc
	286
	287	!
	288	!-- Initialization of the canopy coverage in the model domain:
	289	!-- Setting the parameter canopy_mode = 'block' initializes a canopy, which
	290	!-- fully covers the domain surface
	291	SELECT CASE ( TRIM( canopy_mode ) )
	292
	293	CASE( 'block' )
	294
	295	DO i = nxlg, nxrg
	296	DO j = nysg, nyng
	297	lad_s(:,j,i) = lad(:)
	298	ENDDO
	299	ENDDO
	300
	301	CASE DEFAULT
	302
	303	!
	304	!-- The DEFAULT case is reached either if the parameter
	305	!-- canopy mode contains a wrong character string or if the
	306	!-- user has coded a special case in the user interface.
	307	!-- There, the subroutine user_init_plant_canopy checks
	308	!-- which of these two conditions applies.
	309	CALL user_init_plant_canopy
	310
	311	END SELECT
	312
	313	!
	314	!-- Initialization of the canopy heat source distribution
	315	IF ( cthf /= 0.0_wp ) THEN
	316	!
	317	!-- Piecewise calculation of the leaf area index by vertical
	318	!-- integration of the leaf area density
	319	cum_lai_hf(:,:,:) = 0.0_wp
	320	DO i = nxlg, nxrg
	321	DO j = nysg, nyng
	322	DO k = pch_index-1, 0, -1
	323	IF ( k == pch_index-1 ) THEN
	324	cum_lai_hf(k,j,i) = cum_lai_hf(k+1,j,i) + &
	325	( 0.5_wp * lad_s(k+1,j,i) * &
	326	( zw(k+1) - zu(k+1) ) ) + &
	327	( 0.5_wp * ( 0.5_wp * ( lad_s(k+1,j,i) + &
	328	lad_s(k,j,i) ) + &
	329	lad_s(k+1,j,i) ) * &
	330	( zu(k+1) - zw(k) ) )
	331	ELSE
	332	cum_lai_hf(k,j,i) = cum_lai_hf(k+1,j,i) + &
	333	( 0.5_wp * ( 0.5_wp * ( lad_s(k+2,j,i) + &
	334	lad_s(k+1,j,i) ) + &
	335	lad_s(k+1,j,i) ) * &
	336	( zw(k+1) - zu(k+1) ) ) + &
	337	( 0.5_wp * ( 0.5_wp * ( lad_s(k+1,j,i) + &
	338	lad_s(k,j,i) ) + &
	339	lad_s(k+1,j,i) ) * &
	340	( zu(k+1) - zw(k) ) )
	341	ENDIF
	342	ENDDO
	343	ENDDO
	344	ENDDO
	345
	346	!
	347	!-- Calculation of the upward kinematic vertical heat flux within the
	348	!-- canopy
	349	DO i = nxlg, nxrg
	350	DO j = nysg, nyng
	351	DO k = 0, pch_index
	352	canopy_heat_flux(k,j,i) = cthf * &
	353	exp( -0.6_wp * cum_lai_hf(k,j,i) )
	354	ENDDO
	355	ENDDO
	356	ENDDO
	357
	358	!
	359	!-- The surface heat flux is set to the surface value of the calculated
	360	!-- in-canopy heat flux distribution
	361	shf(:,:) = canopy_heat_flux(0,:,:)
	362
	363	ENDIF
	364
	365
	366
	367	END SUBROUTINE init_plant_canopy
	368
	369
	370
	371	!------------------------------------------------------------------------------!
	372	! Description:
	373	! ------------
[1682]	374	!> Calculation of the tendency terms, accounting for the effect of the plant
	375	!> canopy on momentum and scalar quantities.
	376	!>
	377	!> The canopy is located where the leaf area density lad_s(k,j,i) > 0.0
	378	!> (defined on scalar grid), as initialized in subroutine init_plant_canopy.
	379	!> The lad on the w-grid is vertically interpolated from the surrounding
	380	!> lad_s. The upper boundary of the canopy is defined on the w-grid at
	381	!> k = pch_index. Here, the lad is zero.
	382	!>
	383	!> The canopy drag must be limited (previously accounted for by calculation of
	384	!> a limiting canopy timestep for the determination of the maximum LES timestep
	385	!> in subroutine timestep), since it is physically impossible that the canopy
	386	!> drag alone can locally change the sign of a velocity component. This
	387	!> limitation is realized by calculating preliminary tendencies and velocities.
	388	!> It is subsequently checked if the preliminary new velocity has a different
	389	!> sign than the current velocity. If so, the tendency is limited in a way that
	390	!> the velocity can at maximum be reduced to zero by the canopy drag.
	391	!>
	392	!>
	393	!> Call for all grid points
[1484]	394	!------------------------------------------------------------------------------!
[138]	395	SUBROUTINE plant_canopy_model( component )
	396
	397
[1320]	398	USE control_parameters, &
[1484]	399	ONLY: dt_3d, message_string
[1320]	400
	401	USE kinds
	402
[138]	403	IMPLICIT NONE
	404
[1682]	405	INTEGER(iwp) :: component !< prognostic variable (u,v,w,pt,q,e)
	406	INTEGER(iwp) :: i !< running index
	407	INTEGER(iwp) :: j !< running index
	408	INTEGER(iwp) :: k !< running index
[1484]	409
[1682]	410	REAL(wp) :: ddt_3d !< inverse of the LES timestep (dt_3d)
	411	REAL(wp) :: lad_local !< local lad value
	412	REAL(wp) :: pre_tend !< preliminary tendency
	413	REAL(wp) :: pre_u !< preliminary u-value
	414	REAL(wp) :: pre_v !< preliminary v-value
	415	REAL(wp) :: pre_w !< preliminary w-value
[1484]	416
	417
	418	ddt_3d = 1.0_wp / dt_3d
[138]	419
	420	!
[1484]	421	!-- Compute drag for the three velocity components and the SGS-TKE:
[138]	422	SELECT CASE ( component )
	423
	424	!
	425	!-- u-component
	426	CASE ( 1 )
	427	DO i = nxlu, nxr
	428	DO j = nys, nyn
	429	DO k = nzb_u_inner(j,i)+1, pch_index
[1484]	430
	431	!
	432	!-- In order to create sharp boundaries of the plant canopy,
	433	!-- the lad on the u-grid at index (k,j,i) is equal to
	434	!-- lad_s(k,j,i), rather than being interpolated from the
	435	!-- surrounding lad_s, because this would yield smaller lad
	436	!-- at the canopy boundaries than inside of the canopy.
	437	!-- For the same reason, the lad at the rightmost(i+1)canopy
	438	!-- boundary on the u-grid equals lad_s(k,j,i).
	439	lad_local = lad_s(k,j,i)
	440	IF ( lad_local == 0.0_wp .AND. &
	441	lad_s(k,j,i-1) > 0.0_wp ) THEN
	442	lad_local = lad_s(k,j,i-1)
	443	ENDIF
	444
	445	pre_tend = 0.0_wp
	446	pre_u = 0.0_wp
	447	!
	448	!-- Calculate preliminary value (pre_tend) of the tendency
	449	pre_tend = - cdc * &
	450	lad_local * &
	451	SQRT( u(k,j,i)**2 + &
	452	( 0.25_wp * ( v(k,j,i-1) + &
	453	v(k,j,i) + &
	454	v(k,j+1,i) + &
	455	v(k,j+1,i-1) ) &
	456	)**2 + &
	457	( 0.25_wp * ( w(k-1,j,i-1) + &
	458	w(k-1,j,i) + &
	459	w(k,j,i-1) + &
	460	w(k,j,i) ) &
	461	)**2 &
	462	) * &
	463	u(k,j,i)
	464
	465	!
	466	!-- Calculate preliminary new velocity, based on pre_tend
	467	pre_u = u(k,j,i) + dt_3d * pre_tend
	468	!
	469	!-- Compare sign of old velocity and new preliminary velocity,
	470	!-- and in case the signs are different, limit the tendency
	471	IF ( SIGN(pre_u,u(k,j,i)) /= pre_u ) THEN
	472	pre_tend = - u(k,j,i) * ddt_3d
	473	ELSE
	474	pre_tend = pre_tend
	475	ENDIF
	476	!
	477	!-- Calculate final tendency
	478	tend(k,j,i) = tend(k,j,i) + pre_tend
	479
[138]	480	ENDDO
	481	ENDDO
	482	ENDDO
	483
	484	!
	485	!-- v-component
	486	CASE ( 2 )
	487	DO i = nxl, nxr
	488	DO j = nysv, nyn
	489	DO k = nzb_v_inner(j,i)+1, pch_index
[1484]	490
	491	!
	492	!-- In order to create sharp boundaries of the plant canopy,
	493	!-- the lad on the v-grid at index (k,j,i) is equal to
	494	!-- lad_s(k,j,i), rather than being interpolated from the
	495	!-- surrounding lad_s, because this would yield smaller lad
	496	!-- at the canopy boundaries than inside of the canopy.
	497	!-- For the same reason, the lad at the northmost(j+1) canopy
	498	!-- boundary on the v-grid equals lad_s(k,j,i).
	499	lad_local = lad_s(k,j,i)
	500	IF ( lad_local == 0.0_wp .AND. &
	501	lad_s(k,j-1,i) > 0.0_wp ) THEN
	502	lad_local = lad_s(k,j-1,i)
	503	ENDIF
	504
	505	pre_tend = 0.0_wp
	506	pre_v = 0.0_wp
	507	!
	508	!-- Calculate preliminary value (pre_tend) of the tendency
	509	pre_tend = - cdc * &
	510	lad_local * &
	511	SQRT( ( 0.25_wp * ( u(k,j-1,i) + &
	512	u(k,j-1,i+1) + &
	513	u(k,j,i) + &
	514	u(k,j,i+1) ) &
	515	)**2 + &
	516	v(k,j,i)**2 + &
	517	( 0.25_wp * ( w(k-1,j-1,i) + &
	518	w(k-1,j,i) + &
	519	w(k,j-1,i) + &
	520	w(k,j,i) ) &
	521	)**2 &
	522	) * &
	523	v(k,j,i)
	524
	525	!
	526	!-- Calculate preliminary new velocity, based on pre_tend
	527	pre_v = v(k,j,i) + dt_3d * pre_tend
	528	!
	529	!-- Compare sign of old velocity and new preliminary velocity,
	530	!-- and in case the signs are different, limit the tendency
	531	IF ( SIGN(pre_v,v(k,j,i)) /= pre_v ) THEN
	532	pre_tend = - v(k,j,i) * ddt_3d
	533	ELSE
	534	pre_tend = pre_tend
	535	ENDIF
	536	!
	537	!-- Calculate final tendency
	538	tend(k,j,i) = tend(k,j,i) + pre_tend
	539
[138]	540	ENDDO
	541	ENDDO
	542	ENDDO
	543
	544	!
	545	!-- w-component
	546	CASE ( 3 )
	547	DO i = nxl, nxr
	548	DO j = nys, nyn
[1484]	549	DO k = nzb_w_inner(j,i)+1, pch_index-1
	550
	551	pre_tend = 0.0_wp
	552	pre_w = 0.0_wp
	553	!
	554	!-- Calculate preliminary value (pre_tend) of the tendency
	555	pre_tend = - cdc * &
	556	(0.5_wp * &
	557	( lad_s(k+1,j,i) + lad_s(k,j,i) )) * &
	558	SQRT( ( 0.25_wp * ( u(k,j,i) + &
	559	u(k,j,i+1) + &
	560	u(k+1,j,i) + &
	561	u(k+1,j,i+1) ) &
	562	)**2 + &
	563	( 0.25_wp * ( v(k,j,i) + &
	564	v(k,j+1,i) + &
	565	v(k+1,j,i) + &
	566	v(k+1,j+1,i) ) &
	567	)**2 + &
	568	w(k,j,i)**2 &
	569	) * &
	570	w(k,j,i)
	571	!
	572	!-- Calculate preliminary new velocity, based on pre_tend
	573	pre_w = w(k,j,i) + dt_3d * pre_tend
	574	!
	575	!-- Compare sign of old velocity and new preliminary velocity,
	576	!-- and in case the signs are different, limit the tendency
	577	IF ( SIGN(pre_w,w(k,j,i)) /= pre_w ) THEN
	578	pre_tend = - w(k,j,i) * ddt_3d
	579	ELSE
	580	pre_tend = pre_tend
	581	ENDIF
	582	!
	583	!-- Calculate final tendency
	584	tend(k,j,i) = tend(k,j,i) + pre_tend
	585
[138]	586	ENDDO
	587	ENDDO
	588	ENDDO
	589
	590	!
[153]	591	!-- potential temperature
[138]	592	CASE ( 4 )
	593	DO i = nxl, nxr
	594	DO j = nys, nyn
	595	DO k = nzb_s_inner(j,i)+1, pch_index
[1484]	596	tend(k,j,i) = tend(k,j,i) + &
	597	( canopy_heat_flux(k,j,i) - &
	598	canopy_heat_flux(k-1,j,i) ) / dzw(k)
[153]	599	ENDDO
	600	ENDDO
	601	ENDDO
	602
	603	!
	604	!-- scalar concentration
	605	CASE ( 5 )
	606	DO i = nxl, nxr
	607	DO j = nys, nyn
	608	DO k = nzb_s_inner(j,i)+1, pch_index
[1484]	609	tend(k,j,i) = tend(k,j,i) - &
	610	lsec * &
	611	lad_s(k,j,i) * &
	612	SQRT( ( 0.5_wp * ( u(k,j,i) + &
	613	u(k,j,i+1) ) &
	614	)**2 + &
	615	( 0.5_wp * ( v(k,j,i) + &
	616	v(k,j+1,i) ) &
	617	)**2 + &
	618	( 0.5_wp * ( w(k-1,j,i) + &
	619	w(k,j,i) ) &
	620	)**2 &
	621	) * &
	622	( q(k,j,i) - lsc )
[153]	623	ENDDO
	624	ENDDO
	625	ENDDO
	626
	627	!
	628	!-- sgs-tke
	629	CASE ( 6 )
	630	DO i = nxl, nxr
	631	DO j = nys, nyn
	632	DO k = nzb_s_inner(j,i)+1, pch_index
[1484]	633	tend(k,j,i) = tend(k,j,i) - &
	634	2.0_wp * cdc * &
	635	lad_s(k,j,i) * &
	636	SQRT( ( 0.5_wp * ( u(k,j,i) + &
	637	u(k,j,i+1) ) &
	638	)**2 + &
	639	( 0.5_wp * ( v(k,j,i) + &
	640	v(k,j+1,i) ) &
	641	)**2 + &
	642	( 0.5_wp * ( w(k,j,i) + &
	643	w(k+1,j,i) ) &
	644	)**2 &
	645	) * &
	646	e(k,j,i)
[138]	647	ENDDO
	648	ENDDO
	649	ENDDO
[1484]	650
	651
[138]	652	CASE DEFAULT
	653
[257]	654	WRITE( message_string, * ) 'wrong component: ', component
	655	CALL message( 'plant_canopy_model', 'PA0279', 1, 2, 0, 6, 0 )
[138]	656
	657	END SELECT
	658
	659	END SUBROUTINE plant_canopy_model
	660
	661
	662	!------------------------------------------------------------------------------!
[1484]	663	! Description:
	664	! ------------
[1682]	665	!> Calculation of the tendency terms, accounting for the effect of the plant
	666	!> canopy on momentum and scalar quantities.
	667	!>
	668	!> The canopy is located where the leaf area density lad_s(k,j,i) > 0.0
	669	!> (defined on scalar grid), as initialized in subroutine init_plant_canopy.
	670	!> The lad on the w-grid is vertically interpolated from the surrounding
	671	!> lad_s. The upper boundary of the canopy is defined on the w-grid at
	672	!> k = pch_index. Here, the lad is zero.
	673	!>
	674	!> The canopy drag must be limited (previously accounted for by calculation of
	675	!> a limiting canopy timestep for the determination of the maximum LES timestep
	676	!> in subroutine timestep), since it is physically impossible that the canopy
	677	!> drag alone can locally change the sign of a velocity component. This
	678	!> limitation is realized by calculating preliminary tendencies and velocities.
	679	!> It is subsequently checked if the preliminary new velocity has a different
	680	!> sign than the current velocity. If so, the tendency is limited in a way that
	681	!> the velocity can at maximum be reduced to zero by the canopy drag.
	682	!>
	683	!>
	684	!> Call for grid point i,j
[138]	685	!------------------------------------------------------------------------------!
	686	SUBROUTINE plant_canopy_model_ij( i, j, component )
	687
	688
[1320]	689	USE control_parameters, &
[1484]	690	ONLY: dt_3d, message_string
[1320]	691
	692	USE kinds
	693
[138]	694	IMPLICIT NONE
	695
[1682]	696	INTEGER(iwp) :: component !< prognostic variable (u,v,w,pt,q,e)
	697	INTEGER(iwp) :: i !< running index
	698	INTEGER(iwp) :: j !< running index
	699	INTEGER(iwp) :: k !< running index
[138]	700
[1682]	701	REAL(wp) :: ddt_3d !< inverse of the LES timestep (dt_3d)
	702	REAL(wp) :: lad_local !< local lad value
	703	REAL(wp) :: pre_tend !< preliminary tendency
	704	REAL(wp) :: pre_u !< preliminary u-value
	705	REAL(wp) :: pre_v !< preliminary v-value
	706	REAL(wp) :: pre_w !< preliminary w-value
[1484]	707
	708
	709	ddt_3d = 1.0_wp / dt_3d
	710
[138]	711	!
[1484]	712	!-- Compute drag for the three velocity components and the SGS-TKE
[142]	713	SELECT CASE ( component )
[138]	714
	715	!
[142]	716	!-- u-component
[1484]	717	CASE ( 1 )
	718	DO k = nzb_u_inner(j,i)+1, pch_index
[138]	719
	720	!
[1484]	721	!-- In order to create sharp boundaries of the plant canopy,
	722	!-- the lad on the u-grid at index (k,j,i) is equal to lad_s(k,j,i),
	723	!-- rather than being interpolated from the surrounding lad_s,
	724	!-- because this would yield smaller lad at the canopy boundaries
	725	!-- than inside of the canopy.
	726	!-- For the same reason, the lad at the rightmost(i+1)canopy
	727	!-- boundary on the u-grid equals lad_s(k,j,i).
	728	lad_local = lad_s(k,j,i)
	729	IF ( lad_local == 0.0_wp .AND. &
	730	lad_s(k,j,i-1) > 0.0_wp ) THEN
	731	lad_local = lad_s(k,j,i-1)
	732	ENDIF
	733
	734	pre_tend = 0.0_wp
	735	pre_u = 0.0_wp
	736	!
	737	!-- Calculate preliminary value (pre_tend) of the tendency
	738	pre_tend = - cdc * &
	739	lad_local * &
	740	SQRT( u(k,j,i)**2 + &
	741	( 0.25_wp * ( v(k,j,i-1) + &
	742	v(k,j,i) + &
	743	v(k,j+1,i) + &
	744	v(k,j+1,i-1) ) &
	745	)**2 + &
	746	( 0.25_wp * ( w(k-1,j,i-1) + &
	747	w(k-1,j,i) + &
	748	w(k,j,i-1) + &
	749	w(k,j,i) ) &
	750	)**2 &
	751	) * &
	752	u(k,j,i)
	753
	754	!
	755	!-- Calculate preliminary new velocity, based on pre_tend
	756	pre_u = u(k,j,i) + dt_3d * pre_tend
	757	!
	758	!-- Compare sign of old velocity and new preliminary velocity,
	759	!-- and in case the signs are different, limit the tendency
	760	IF ( SIGN(pre_u,u(k,j,i)) /= pre_u ) THEN
	761	pre_tend = - u(k,j,i) * ddt_3d
	762	ELSE
	763	pre_tend = pre_tend
	764	ENDIF
	765	!
	766	!-- Calculate final tendency
	767	tend(k,j,i) = tend(k,j,i) + pre_tend
	768	ENDDO
	769
	770
	771	!
[142]	772	!-- v-component
[1484]	773	CASE ( 2 )
	774	DO k = nzb_v_inner(j,i)+1, pch_index
[138]	775
	776	!
[1484]	777	!-- In order to create sharp boundaries of the plant canopy,
	778	!-- the lad on the v-grid at index (k,j,i) is equal to lad_s(k,j,i),
	779	!-- rather than being interpolated from the surrounding lad_s,
	780	!-- because this would yield smaller lad at the canopy boundaries
	781	!-- than inside of the canopy.
	782	!-- For the same reason, the lad at the northmost(j+1)canopy
	783	!-- boundary on the v-grid equals lad_s(k,j,i).
	784	lad_local = lad_s(k,j,i)
	785	IF ( lad_local == 0.0_wp .AND. &
	786	lad_s(k,j-1,i) > 0.0_wp ) THEN
	787	lad_local = lad_s(k,j-1,i)
	788	ENDIF
	789
	790	pre_tend = 0.0_wp
	791	pre_v = 0.0_wp
	792	!
	793	!-- Calculate preliminary value (pre_tend) of the tendency
	794	pre_tend = - cdc * &
	795	lad_local * &
	796	SQRT( ( 0.25_wp * ( u(k,j-1,i) + &
	797	u(k,j-1,i+1) + &
	798	u(k,j,i) + &
	799	u(k,j,i+1) ) &
	800	)**2 + &
	801	v(k,j,i)**2 + &
	802	( 0.25_wp * ( w(k-1,j-1,i) + &
	803	w(k-1,j,i) + &
	804	w(k,j-1,i) + &
	805	w(k,j,i) ) &
	806	)**2 &
	807	) * &
	808	v(k,j,i)
	809
	810	!
	811	!-- Calculate preliminary new velocity, based on pre_tend
	812	pre_v = v(k,j,i) + dt_3d * pre_tend
	813	!
	814	!-- Compare sign of old velocity and new preliminary velocity,
	815	!-- and in case the signs are different, limit the tendency
	816	IF ( SIGN(pre_v,v(k,j,i)) /= pre_v ) THEN
	817	pre_tend = - v(k,j,i) * ddt_3d
	818	ELSE
	819	pre_tend = pre_tend
	820	ENDIF
	821	!
	822	!-- Calculate final tendency
	823	tend(k,j,i) = tend(k,j,i) + pre_tend
	824	ENDDO
	825
	826
	827	!
[142]	828	!-- w-component
[1484]	829	CASE ( 3 )
	830	DO k = nzb_w_inner(j,i)+1, pch_index-1
[138]	831
[1484]	832	pre_tend = 0.0_wp
	833	pre_w = 0.0_wp
[138]	834	!
[1484]	835	!-- Calculate preliminary value (pre_tend) of the tendency
	836	pre_tend = - cdc * &
	837	(0.5_wp * &
	838	( lad_s(k+1,j,i) + lad_s(k,j,i) )) * &
	839	SQRT( ( 0.25_wp * ( u(k,j,i) + &
	840	u(k,j,i+1) + &
	841	u(k+1,j,i) + &
	842	u(k+1,j,i+1) ) &
	843	)**2 + &
	844	( 0.25_wp * ( v(k,j,i) + &
	845	v(k,j+1,i) + &
	846	v(k+1,j,i) + &
	847	v(k+1,j+1,i) ) &
	848	)**2 + &
	849	w(k,j,i)**2 &
	850	) * &
	851	w(k,j,i)
	852	!
	853	!-- Calculate preliminary new velocity, based on pre_tend
	854	pre_w = w(k,j,i) + dt_3d * pre_tend
	855	!
	856	!-- Compare sign of old velocity and new preliminary velocity,
	857	!-- and in case the signs are different, limit the tendency
	858	IF ( SIGN(pre_w,w(k,j,i)) /= pre_w ) THEN
	859	pre_tend = - w(k,j,i) * ddt_3d
	860	ELSE
	861	pre_tend = pre_tend
	862	ENDIF
	863	!
	864	!-- Calculate final tendency
	865	tend(k,j,i) = tend(k,j,i) + pre_tend
	866	ENDDO
	867
	868	!
[153]	869	!-- potential temperature
	870	CASE ( 4 )
	871	DO k = nzb_s_inner(j,i)+1, pch_index
[1484]	872	tend(k,j,i) = tend(k,j,i) + &
	873	( canopy_heat_flux(k,j,i) - &
	874	canopy_heat_flux(k-1,j,i) ) / dzw(k)
[153]	875	ENDDO
	876
	877
	878	!
	879	!-- scalar concentration
	880	CASE ( 5 )
	881	DO k = nzb_s_inner(j,i)+1, pch_index
[1484]	882	tend(k,j,i) = tend(k,j,i) - &
	883	lsec * &
	884	lad_s(k,j,i) * &
	885	SQRT( ( 0.5_wp * ( u(k,j,i) + &
	886	u(k,j,i+1) ) &
	887	)**2 + &
	888	( 0.5_wp * ( v(k,j,i) + &
	889	v(k,j+1,i) ) &
	890	)**2 + &
	891	( 0.5_wp * ( w(k-1,j,i) + &
	892	w(k,j,i) ) &
	893	)**2 &
	894	) * &
	895	( q(k,j,i) - lsc )
[153]	896	ENDDO
	897
	898	!
[142]	899	!-- sgs-tke
[1484]	900	CASE ( 6 )
	901	DO k = nzb_s_inner(j,i)+1, pch_index
	902	tend(k,j,i) = tend(k,j,i) - &
	903	2.0_wp * cdc * &
	904	lad_s(k,j,i) * &
	905	SQRT( ( 0.5_wp * ( u(k,j,i) + &
	906	u(k,j,i+1) ) &
	907	)**2 + &
	908	( 0.5_wp * ( v(k,j,i) + &
	909	v(k,j+1,i) ) &
	910	)**2 + &
	911	( 0.5_wp * ( w(k,j,i) + &
	912	w(k+1,j,i) ) &
	913	)**2 &
	914	) * &
	915	e(k,j,i)
	916	ENDDO
[138]	917
[142]	918	CASE DEFAULT
[138]	919
[257]	920	WRITE( message_string, * ) 'wrong component: ', component
	921	CALL message( 'plant_canopy_model', 'PA0279', 1, 2, 0, 6, 0 )
[138]	922
[142]	923	END SELECT
[138]	924
	925	END SUBROUTINE plant_canopy_model_ij
	926
	927	END MODULE plant_canopy_model_mod

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

Download in other formats:

| Impressum | ©Leibniz Universität Hannover |