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source: palm/trunk/SOURCE/land_surface_model.f90 @ 1512

Last change on this file since 1512 was 1501, checked in by maronga, 10 years ago
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[1496]	1	MODULE land_surface_model_mod
	2
	3	!--------------------------------------------------------------------------------!
	4	! This file is part of PALM.
	5	!
	6	! PALM is free software: you can redistribute it and/or modify it under the terms
	7	! of the GNU General Public License as published by the Free Software Foundation,
	8	! either version 3 of the License, or (at your option) any later version.
	9	!
	10	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
	11	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
	12	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
	13	!
	14	! You should have received a copy of the GNU General Public License along with
	15	! PALM. If not, see <http://www.gnu.org/licenses/>.
	16	!
	17	! Copyright 1997-2014 Leibniz Universitaet Hannover
	18	!--------------------------------------------------------------------------------!
	19	!
	20	! Current revisions:
	21	! -----------------
	22	!
[1501]	23	!
[1496]	24	! Former revisions:
	25	! -----------------
	26	! $Id: land_surface_model.f90 1501 2014-12-03 17:44:29Z suehring $
	27	!
[1501]	28	! 1500 2014-12-03 17:42:41Z maronga
	29	! Corrected calculation of aerodynamic resistance (r_a).
	30	! Precipitation is now added to liquid water reservoir using LE_liq.
	31	! Added support for dry runs.
	32	!
[1497]	33	! 1496 2014-12-02 17:25:50Z maronga
	34	! Initial revision
	35	!
[1496]	36	!
	37	! Description:
	38	! ------------
	39	! Land surface model, consisting of a solver for the energy balance at the
	40	! surface and a four layer soil scheme. The scheme is similar to the TESSEL
	41	! scheme implemented in the ECMWF IFS model, with modifications according to
	42	! H-TESSEL. The implementation is based on the formulation implemented in the
	43	! DALES model.
[1500]	44	!
	45	! To do list:
	46	! -----------
	47	! - Add support for binary I/O support
	48	! - Add support for lsm data output
	49	! - Check for time step criterion
	50	! - Check use with RK-2 and Euler time-stepping
	51	! - Adaption for use with cloud physics (liquid water potential temperature)
	52	! - Check reaction of plants at wilting point and at atmospheric saturation
	53	! - Consider partial absorption of the net shortwave radiation by the skin layer
	54	! - Allow for water surfaces, check performance for bare soils
[1496]	55	!------------------------------------------------------------------------------!
	56	USE arrays_3d, &
	57	ONLY: pt, pt_p, q, q_p, qsws, rif, shf, ts, us, z0, z0h
	58
	59	USE cloud_parameters, &
[1500]	60	ONLY: cp, l_d_r, l_v, precipitation_rate, rho_l, r_d, r_v
[1496]	61
	62	USE control_parameters, &
	63	ONLY: dt_3d, humidity, intermediate_timestep_count, &
[1500]	64	intermediate_timestep_count_max, precipitation, pt_surface, &
	65	rho_surface, surface_pressure, timestep_scheme, tsc
[1496]	66
	67	USE indices, &
	68	ONLY: nxlg, nxrg, nyng, nysg, nzb_s_inner
	69
	70	USE kinds
	71
	72	USE radiation_model_mod, &
	73	ONLY: Rn, SW_in, sigma_SB
	74
	75
	76	IMPLICIT NONE
	77
	78	!
	79	!-- LSM model constants
	80	INTEGER(iwp), PARAMETER :: soil_layers = 4 !: number of soil layers (fixed for now)
	81
	82	REAL(wp), PARAMETER :: &
	83	b_CH = 6.04_wp, & ! Clapp & Hornberger exponent
	84	lambda_h_dry = 0.19_wp, & ! heat conductivity for dry soil
	85	lambda_h_sm = 3.44_wp, & ! heat conductivity of the soil matrix
	86	lambda_h_water = 0.57_wp, & ! heat conductivity of water
	87	psi_sat = -0.388_wp, & ! soil matrix potential at saturation
	88	rhoC_soil = 2.19E6_wp, & ! volumetric heat capacity of soil
	89	rhoC_water = 4.20E6_wp, & ! volumetric heat capacity of water
	90	m_max_depth = 0.0002_wp ! Maximum capacity of the water reservoir (m)
	91
	92
	93	!
	94	!-- LSM variables
	95	INTEGER(iwp) :: veg_type = 2, & !: vegetation type, 0: user-defined, 1-19: generic (see list)
	96	soil_type = 3 !: soil type, 0: user-defined, 1-6: generic (see list)
	97
	98	LOGICAL :: conserve_water_content = .TRUE., & !: open or closed bottom surface for the soil model
	99	land_surface = .FALSE. !: flag parameter indicating wheather the lsm is used
	100
	101	! value 9999999.9_wp -> generic available or user-defined value must be set
	102	! otherwise -> no generic variable and user setting is optional
	103	REAL(wp) :: alpha_VanGenuchten = 0.0_wp, & !: NAMELIST alpha_VG
	104	canopy_resistance_coefficient = 0.0_wp, & !: NAMELIST gD
	105	C_skin = 20000.0_wp, & !: Skin heat capacity
	106	drho_l_lv, & !: (rho_l * l_v)**-1
	107	exn, & !: value of the Exner function
	108	e_s = 0.0_wp, & !: saturation water vapour pressure
	109	field_capacity = 0.0_wp, & !: NAMELIST m_fc
	110	f_shortwave_incoming = 9999999.9_wp, & !: NAMELIST f_SW_in
	111	hydraulic_conductivity = 0.0_wp, & !: NAMELIST gamma_w_sat
	112	Ke = 0.0_wp, & !: Kersten number
	113	lambda_skin_stable = 9999999.9_wp, & !: NAMELIST lambda_skin_s
	114	lambda_skin_unstable = 9999999.9_wp, & !: NAMELIST lambda_skin_u
	115	leaf_area_index = 9999999.9_wp, & !: NAMELIST LAI
	116	l_VanGenuchten = 0.0_WP, & !: NAMELIST l_VG
	117	min_canopy_resistance = 110.0_wp, & !: NAMELIST r_s_min
	118	m_total = 0.0_wp, & !: weighed total water content of the soil (m3/m3)
	119	n_VanGenuchten = 0.0_WP, & !: NAMELIST n_VG
	120	q_s = 0.0_wp, & !: saturation specific humidity
	121	residual_moisture = 0.0_wp, & !: NAMELIST m_res
	122	rho_cp, & !: rho_surface * cp
	123	rho_lv, & !: rho * l_v
	124	rd_d_rv, & !: r_d / r_v
	125	saturation_moisture = 0.0_wp, & !: NAMELIST m_sat
	126	vegetation_coverage = 9999999.9_wp, & !: NAMELIST c_veg
	127	wilting_point = 0.0_wp !: NAMELIST m_wilt
	128
	129	REAL(wp), DIMENSION(0:soil_layers-1) :: &
	130	ddz_soil, & !: 1/dz_soil
	131	ddz_soil_stag, & !: 1/dz_soil_stag
	132	dz_soil, & !: soil grid spacing (center-center)
	133	dz_soil_stag, & !: soil grid spacing (edge-edge)
	134	root_extr = 0.0_wp, & !: root extraction
	135	root_fraction = (/0.35_wp, 0.38_wp, 0.23_wp, 0.04_wp/), & !: distribution of root surface area to the individual soil layers
	136	soil_level = (/0.07_wp, 0.28_wp, 1.00_wp, 2.89_wp/), & !: soil layer depths (m)
[1500]	137	soil_moisture = 0.0_wp !: soil moisture content (m3/m3)
[1496]	138
	139	REAL(wp), DIMENSION(0:soil_layers) :: &
	140	soil_temperature = 9999999.9_wp !: soil temperature (K)
	141
	142	#if defined( __nopointer )
	143	REAL(wp), DIMENSION(:,:), ALLOCATABLE, TARGET :: T_0, & !: skin temperature (K)
	144	T_0_p, & !: progn. skin temperature (K)
	145	m_liq, & !: liquid water reservoir (m)
	146	m_liq_p !: progn. liquid water reservoir (m)
	147	#else
	148	REAL(wp), DIMENSION(:,:), POINTER :: T_0, &
	149	T_0_p, &
	150	m_liq, &
	151	m_liq_p
	152
	153	REAL(wp), DIMENSION(:,:), ALLOCATABLE, TARGET :: T_0_1, T_0_2, &
	154	m_liq_1, m_liq_2
	155	#endif
	156
	157	!
	158	!-- Temporal tendencies for time stepping
	159	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: tT_0_m, & !: skin temperature tendency (K)
	160	tm_liq_m !: liquid water reservoir tendency (m)
	161
	162	!
	163	!-- Energy balance variables
	164	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: &
	165	alpha_VG, & !: coef. of Van Genuchten
	166	c_liq, & !: liquid water coverage (of vegetated area)
	167	c_veg, & !: vegetation coverage
	168	f_SW_in, & !: ?
	169	G, & !: surface soil heat flux
	170	H, & !: surface flux of sensible heat
	171	gamma_w_sat, & !: hydraulic conductivity at saturation
	172	gD, & !: coefficient for dependence of r_canopy on water vapour pressure deficit
	173	LAI, & !: leaf area index
	174	LE, & !: surface flux of latent heat (total)
	175	LE_veg, & !: surface flux of latent heat (vegetation portion)
	176	LE_soil, & !: surface flux of latent heat (soil portion)
	177	LE_liq, & !: surface flux of latent heat (liquid water portion)
	178	lambda_h_sat, & !: heat conductivity for dry soil
	179	lambda_skin_s, & !: coupling between skin and soil (depends on vegetation type)
	180	lambda_skin_u, & !: coupling between skin and soil (depends on vegetation type)
	181	l_VG, & !: coef. of Van Genuchten
	182	m_fc, & !: soil moisture at field capacity (m3/m3)
	183	m_res, & !: residual soil moisture
	184	m_sat, & !: saturation soil moisture (m3/m3)
	185	m_wilt, & !: soil moisture at permanent wilting point (m3/m3)
	186	n_VG, & !: coef. Van Genuchten
	187	r_a, & !: aerodynamic resistance
	188	r_canopy, & !: canopy resistance
	189	r_soil, & !: soil resitance
	190	r_soil_min, & !: minimum soil resistance
	191	r_s, & !: total surface resistance (combination of r_soil and r_canopy)
	192	r_s_min !: minimum canopy resistance
	193
	194	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: &
	195	lambda_h, & !: heat conductivity of soil (?)
	196	lambda_w, & !: hydraulic diffusivity of soil (?)
	197	gamma_w, & !: hydraulic conductivity of soil (?)
	198	rhoC_total !: volumetric heat capacity of the actual soil matrix (?)
	199
	200	#if defined( __nopointer )
	201	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE, TARGET :: &
	202	T_soil, & !: Soil temperature (K)
	203	T_soil_p, & !: Prog. soil temperature (K)
	204	m_soil, & !: Soil moisture (m3/m3)
	205	m_soil_p !: Prog. soil moisture (m3/m3)
	206	#else
	207	REAL(wp), DIMENSION(:,:,:), POINTER :: &
	208	T_soil, T_soil_p, &
	209	m_soil, m_soil_p
	210
	211	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE, TARGET :: &
	212	T_soil_1, T_soil_2, &
	213	m_soil_1, m_soil_2
	214
	215
	216	#endif
	217
	218
	219	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: &
	220	tT_soil_m, & !: T_soil storage array
	221	tm_soil_m, & !: m_soil storage array
	222	root_fr !: root fraction (sum=1)
	223
	224	!
	225	!-- Land surface parameters according to the following classes (veg_type)
	226	!-- (0 user defined)
	227	!-- 1 crops, mixed farming
	228	!-- 2 short grass
	229	!-- 3 evergreen needleleaf trees
	230	!-- 4 deciduous needleleaf trees
	231	!-- 5 evergreen broadleaf trees
	232	!-- 6 deciduous broadleaf trees
	233	!-- 7 tall grass
	234	!-- 8 desert
	235	!-- 9 tundra
	236	!-- 10 irrigated crops
	237	!-- 11 semidesert
	238	!-- 12 ice caps and glaciers
	239	!-- 13 bogs and marshes
	240	!-- 14 inland water
	241	!-- 15 ocean
	242	!-- 16 evergreen shrubs
	243	!-- 17 deciduous shrubs
	244	!-- 18 mixed forest/woodland
	245	!-- 19 interrupted forest
	246
	247	!
	248	!-- Land surface parameters I r_s_min, LAI, c_veg, gD
	249	REAL(wp), DIMENSION(0:3,1:19) :: veg_pars = RESHAPE( (/ &
	250	180.0_wp, 3.00_wp, 0.90_wp, 0.00_wp, & ! 1
	251	110.0_wp, 2.00_wp, 0.85_wp, 0.00_wp, & ! 2
	252	500.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 3
	253	500.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 4
	254	175.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 5
	255	240.0_wp, 6.00_wp, 0.99_wp, 0.13_wp, & ! 6
	256	100.0_wp, 2.00_wp, 0.70_wp, 0.00_wp, & ! 7
	257	250.0_wp, 0.50_wp, 0.00_wp, 0.00_wp, & ! 8
	258	80.0_wp, 1.00_wp, 0.50_wp, 0.00_wp, & ! 9
	259	180.0_wp, 3.00_wp, 0.90_wp, 0.00_wp, & ! 10
	260	150.0_wp, 0.50_wp, 0.10_wp, 0.00_wp, & ! 11
	261	0.0_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 12
	262	240.0_wp, 4.00_wp, 0.60_wp, 0.00_wp, & ! 13
	263	0.0_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 14
	264	0.0_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 15
	265	225.0_wp, 3.00_wp, 0.50_wp, 0.00_wp, & ! 16
	266	225.0_wp, 1.50_wp, 0.50_wp, 0.00_wp, & ! 17
	267	250.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 18
	268	175.0_wp, 2.50_wp, 0.90_wp, 0.03_wp & ! 19
	269	/), (/ 4, 19 /) )
	270
	271	!
	272	!-- Land surface parameters II z0, z0h
	273	REAL(wp), DIMENSION(0:1,1:19) :: roughness_par = RESHAPE( (/ &
	274	0.25_wp, 0.25E-2_wp, & ! 1
	275	0.20_wp, 0.20E-2_wp, & ! 2
	276	2.00_wp, 2.00_wp, & ! 3
	277	2.00_wp, 2.00_wp, & ! 4
	278	2.00_wp, 2.00_wp, & ! 5
	279	2.00_wp, 2.00_wp, & ! 6
	280	0.47_wp, 0.47E-2_wp, & ! 7
	281	0.013_wp, 0.013E-2_wp, & ! 8
	282	0.034_wp, 0.034E-2_wp, & ! 9
	283	0.5_wp, 0.50E-2_wp, & ! 10
	284	0.17_wp, 0.17E-2_wp, & ! 11
	285	1.3E-3_wp, 1.3E-4_wp, & ! 12
	286	0.83_wp, 0.83E-2_wp, & ! 13
	287	0.00_wp, 0.00E-2_wp, & ! 14
	288	0.00_wp, 0.00E-2_wp, & ! 15
	289	0.10_wp, 0.10E-2_wp, & ! 16
	290	0.25_wp, 0.25E-2_wp, & ! 17
	291	2.00_wp, 2.00E-2_wp, & ! 18
	292	1.10_wp, 1.10E-2_wp & ! 19
	293	/), (/ 2, 19 /) )
	294
	295	!
	296	!-- Land surface parameters III lambda_skin_s, lambda_skin_u, f_SW_in
	297	REAL(wp), DIMENSION(0:2,1:19) :: skin_pars = RESHAPE( (/ &
	298	10.0_wp, 10.0_wp, 0.05_wp, & ! 1
	299	10.0_wp, 10.0_wp, 0.05_wp, & ! 2
	300	20.0_wp, 15.0_wp, 0.03_wp, & ! 3
	301	20.0_wp, 15.0_wp, 0.03_wp, & ! 4
	302	20.0_wp, 15.0_wp, 0.03_wp, & ! 5
	303	20.0_wp, 15.0_wp, 0.03_wp, & ! 6
	304	10.0_wp, 10.0_wp, 0.05_wp, & ! 7
	305	15.0_wp, 15.0_wp, 0.00_wp, & ! 8
	306	10.0_wp, 10.0_wp, 0.05_wp, & ! 9
	307	10.0_wp, 10.0_wp, 0.05_wp, & ! 10
	308	10.0_wp, 10.0_wp, 0.05_wp, & ! 11
	309	58.0_wp, 58.0_wp, 0.00_wp, & ! 12
	310	10.0_wp, 10.0_wp, 0.05_wp, & ! 13
	311	1.0E20_wp, 1.0E20_wp, 0.00_wp, & ! 14
	312	1.0E20_wp, 1.0E20_wp, 0.00_wp, & ! 15
	313	10.0_wp, 10.0_wp, 0.05_wp, & ! 16
	314	10.0_wp, 10.0_wp, 0.05_wp, & ! 17
	315	20.0_wp, 15.0_wp, 0.03_wp, & ! 18
	316	20.0_wp, 15.0_wp, 0.03_wp & ! 19
	317	/), (/ 3, 19 /) )
	318
	319	!
	320	!-- Root distribution (sum = 1) level 1, level 2, level 3, level 4,
	321	REAL(wp), DIMENSION(0:3,1:19) :: root_distribution = RESHAPE( (/ &
	322	0.24_wp, 0.41_wp, 0.31_wp, 0.04_wp, & ! 1
	323	0.35_wp, 0.38_wp, 0.23_wp, 0.04_wp, & ! 2
	324	0.26_wp, 0.39_wp, 0.29_wp, 0.06_wp, & ! 3
	325	0.26_wp, 0.38_wp, 0.29_wp, 0.07_wp, & ! 4
	326	0.24_wp, 0.38_wp, 0.31_wp, 0.07_wp, & ! 5
	327	0.25_wp, 0.34_wp, 0.27_wp, 0.14_wp, & ! 6
	328	0.27_wp, 0.27_wp, 0.27_wp, 0.09_wp, & ! 7
	329	1.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 8
	330	0.47_wp, 0.45_wp, 0.08_wp, 0.00_wp, & ! 9
	331	0.24_wp, 0.41_wp, 0.31_wp, 0.04_wp, & ! 10
	332	0.17_wp, 0.31_wp, 0.33_wp, 0.19_wp, & ! 11
	333	0.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 12
	334	0.25_wp, 0.34_wp, 0.27_wp, 0.11_wp, & ! 13
	335	0.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 14
	336	0.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 15
	337	0.23_wp, 0.36_wp, 0.30_wp, 0.11_wp, & ! 16
	338	0.23_wp, 0.36_wp, 0.30_wp, 0.11_wp, & ! 17
	339	0.19_wp, 0.35_wp, 0.36_wp, 0.10_wp, & ! 18
	340	0.19_wp, 0.35_wp, 0.36_wp, 0.10_wp & ! 19
	341	/), (/ 4, 19 /) )
	342
	343	!
	344	!-- Soil parameters according to the following porosity classes (soil_type)
	345	!-- (0 user defined)
	346	!-- 1 coarse
	347	!-- 2 medium
	348	!-- 3 medium-fine
	349	!-- 4 fine
	350	!-- 5 very fine
	351	!-- 6 organic
	352	!
	353	!-- Soil parameters I alpha_VG, l_VG, n_VG, gamma_w_sat
	354	REAL(wp), DIMENSION(0:3,1:6) :: soil_pars = RESHAPE( (/ &
	355	3.83_wp, 1.250_wp, 1.38_wp, 6.94E-6_wp, & ! 1
	356	3.14_wp, -2.342_wp, 1.28_wp, 1.16E-6_wp, & ! 2
	357	0.83_wp, -0.588_wp, 1.25_wp, 0.26E-6_wp, & ! 3
	358	3.67_wp, -1.977_wp, 1.10_wp, 2.87E-6_wp, & ! 4
	359	2.65_wp, 2.500_wp, 1.10_wp, 1.74E-6_wp, & ! 5
	360	1.30_wp, 0.400_wp, 1.20_wp, 0.93E-6_wp & ! 6
	361	/), (/ 4, 6 /) )
	362
	363	!
	364	!-- Soil parameters II m_sat, m_fc, m_wilt, m_res
	365	REAL(wp), DIMENSION(0:3,1:6) :: m_soil_pars = RESHAPE( (/ &
	366	0.403_wp, 0.244_wp, 0.059_wp, 0.025_wp, & ! 1
	367	0.439_wp, 0.347_wp, 0.151_wp, 0.010_wp, & ! 2
	368	0.430_wp, 0.383_wp, 0.133_wp, 0.010_wp, & ! 3
	369	0.520_wp, 0.448_wp, 0.279_wp, 0.010_wp, & ! 4
	370	0.614_wp, 0.541_wp, 0.335_wp, 0.010_wp, & ! 5
	371	0.766_wp, 0.663_wp, 0.267_wp, 0.010_wp & ! 6
	372	/), (/ 4, 6 /) )
	373
	374
	375	SAVE
	376
	377
	378	PRIVATE
	379
	380
	381	PUBLIC alpha_VanGenuchten, C_skin, canopy_resistance_coefficient, &
	382	conserve_water_content, field_capacity, f_shortwave_incoming, &
	383	hydraulic_conductivity, init_lsm, lambda_skin_stable, &
	384	lambda_skin_unstable, land_surface, leaf_area_index, &
	385	lsm_energy_balance, lsm_soil_model, l_VanGenuchten, &
	386	min_canopy_resistance, n_VanGenuchten, residual_moisture, &
	387	root_fraction, saturation_moisture, soil_level, soil_moisture, &
	388	soil_temperature, soil_type, vegetation_coverage, veg_type, &
	389	wilting_point
	390
	391	#if defined( __nopointer )
	392	PUBLIC m_liq, m_liq_p, m_soil, m_soil_p, T_0, T_0_p, T_soil, T_soil_p
	393	#else
	394	PUBLIC m_liq, m_liq_1, m_liq_2, m_liq_p, m_soil, m_soil_1, m_soil_2, &
	395	m_soil_p, T_0, T_0_1, T_0_2, T_0_p, T_soil, T_soil_1, T_soil_2, &
	396	T_soil_p
	397	#endif
	398
	399
	400	INTERFACE init_lsm
	401	MODULE PROCEDURE init_lsm
	402	END INTERFACE init_lsm
	403
	404	INTERFACE lsm_energy_balance
	405	MODULE PROCEDURE lsm_energy_balance
	406	END INTERFACE lsm_energy_balance
	407
	408	INTERFACE lsm_soil_model
	409	MODULE PROCEDURE lsm_soil_model
	410	END INTERFACE lsm_soil_model
	411
	412
	413	CONTAINS
	414
	415
	416	!------------------------------------------------------------------------------!
	417	! Description:
	418	! ------------
	419	!-- Initialization of the land surface model
	420	!------------------------------------------------------------------------------!
	421	SUBROUTINE init_lsm
	422
	423
	424	IMPLICIT NONE
	425
	426	INTEGER(iwp) :: i !: running index
	427	INTEGER(iwp) :: j !: running index
	428	INTEGER(iwp) :: k !: running index
	429
	430
	431	!
	432	!-- Calculate frequently used parameters
	433	rho_cp = cp * rho_surface
	434	rd_d_rv = r_d / r_v
	435	rho_lv = rho_surface * l_v
	436	drho_l_lv = 1.0 / (rho_l * l_v)
	437
	438	!
	439	!-- Allocate skin and soil temperature / humidity
	440	#if defined( __nopointer )
	441	ALLOCATE ( T_0(nysg:nyng,nxlg:nxrg) )
	442	ALLOCATE ( T_0_p(nysg:nyng,nxlg:nxrg) )
	443	#else
	444	ALLOCATE ( T_0_1(nysg:nyng,nxlg:nxrg) )
	445	ALLOCATE ( T_0_2(nysg:nyng,nxlg:nxrg) )
	446	#endif
	447
	448	ALLOCATE ( tT_0_m(nysg:nyng,nxlg:nxrg) )
	449
	450	#if defined( __nopointer )
	451	ALLOCATE ( T_soil(0:soil_layers,nysg:nyng,nxlg:nxrg) )
	452	ALLOCATE ( T_soil_p(0:soil_layers,nysg:nyng,nxlg:nxrg) )
	453	#else
	454	ALLOCATE ( T_soil_1(0:soil_layers,nysg:nyng,nxlg:nxrg) )
	455	ALLOCATE ( T_soil_2(0:soil_layers,nysg:nyng,nxlg:nxrg) )
	456	#endif
	457
	458	ALLOCATE ( tT_soil_m(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	459
	460	#if defined( __nopointer )
	461	ALLOCATE ( m_liq(nysg:nyng,nxlg:nxrg) )
	462	ALLOCATE ( m_liq_p(nysg:nyng,nxlg:nxrg) )
	463	#else
	464	ALLOCATE ( m_liq_1(nysg:nyng,nxlg:nxrg) )
	465	ALLOCATE ( m_liq_2(nysg:nyng,nxlg:nxrg) )
	466	#endif
	467
	468	ALLOCATE ( tm_liq_m(nysg:nyng,nxlg:nxrg) )
	469
	470	#if defined( __nopointer )
	471	ALLOCATE ( m_soil(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	472	ALLOCATE ( m_soil_p(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	473	#else
	474	ALLOCATE ( m_soil_1(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	475	ALLOCATE ( m_soil_2(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	476	#endif
	477
	478	ALLOCATE ( tm_soil_m(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	479
	480
	481	#if ! defined( __nopointer )
	482	!
	483	!-- Initial assignment of the pointers
	484	T_soil => T_soil_1; T_soil_p => T_soil_2
	485	T_0 => T_0_1; T_0_p => T_0_2
	486	m_soil => m_soil_1; m_soil_p => m_soil_2
	487	m_liq => m_liq_1; m_liq_p => m_liq_2
	488	#endif
	489
	490	T_0 = 0.0_wp
	491	T_0_p = 0.0_wp
	492	tT_0_m = 0.0_wp
	493
	494	T_soil = 0.0_wp
	495	T_soil_p = 0.0_wp
	496	tT_soil_m = 0.0_wp
	497
	498	m_liq = 0.0_wp
	499	m_liq_p = 0.0_wp
	500	tm_liq_m = 0.0_wp
	501
	502	m_soil = 0.0_wp
	503	m_soil_p = 0.0_wp
	504	tm_soil_m = 0.0_wp
	505
	506	!
	507	!-- Allocate 2D vegetation model arrays
	508	ALLOCATE ( alpha_VG(nysg:nyng,nxlg:nxrg) )
	509	ALLOCATE ( c_liq(nysg:nyng,nxlg:nxrg) )
	510	ALLOCATE ( c_veg(nysg:nyng,nxlg:nxrg) )
	511	ALLOCATE ( f_SW_in(nysg:nyng,nxlg:nxrg) )
	512	ALLOCATE ( G(nysg:nyng,nxlg:nxrg) )
	513	ALLOCATE ( H(nysg:nyng,nxlg:nxrg) )
	514	ALLOCATE ( gamma_w_sat(nysg:nyng,nxlg:nxrg) )
	515	ALLOCATE ( gD(nysg:nyng,nxlg:nxrg) )
	516	ALLOCATE ( LAI(nysg:nyng,nxlg:nxrg) )
	517	ALLOCATE ( LE(nysg:nyng,nxlg:nxrg) )
	518	ALLOCATE ( LE_veg(nysg:nyng,nxlg:nxrg) )
	519	ALLOCATE ( LE_soil(nysg:nyng,nxlg:nxrg) )
	520	ALLOCATE ( LE_liq(nysg:nyng,nxlg:nxrg) )
	521	ALLOCATE ( l_VG(nysg:nyng,nxlg:nxrg) )
	522	ALLOCATE ( lambda_h_sat(nysg:nyng,nxlg:nxrg) )
	523	ALLOCATE ( lambda_skin_u(nysg:nyng,nxlg:nxrg) )
	524	ALLOCATE ( lambda_skin_s(nysg:nyng,nxlg:nxrg) )
	525	ALLOCATE ( m_fc(nysg:nyng,nxlg:nxrg) )
	526	ALLOCATE ( m_res(nysg:nyng,nxlg:nxrg) )
	527	ALLOCATE ( m_sat(nysg:nyng,nxlg:nxrg) )
	528	ALLOCATE ( m_wilt(nysg:nyng,nxlg:nxrg) )
	529	ALLOCATE ( n_VG(nysg:nyng,nxlg:nxrg) )
	530	ALLOCATE ( r_a(nysg:nyng,nxlg:nxrg) )
	531	ALLOCATE ( r_canopy(nysg:nyng,nxlg:nxrg) )
	532	ALLOCATE ( r_soil(nysg:nyng,nxlg:nxrg) )
	533	ALLOCATE ( r_soil_min(nysg:nyng,nxlg:nxrg) )
	534	ALLOCATE ( r_s(nysg:nyng,nxlg:nxrg) )
	535	ALLOCATE ( r_s_min(nysg:nyng,nxlg:nxrg) )
	536
	537	!
	538	!-- Set initial and default values
	539	c_liq = 0.0_wp
	540	c_veg = 0.0_wp
	541	f_SW_in = 0.05_wp
	542	gD = 0.0_wp
	543	LAI = 0.0_wp
	544	lambda_skin_u = 10.0_wp
	545	lambda_skin_s = 10.0_wp
	546
	547
	548	G = 0.0_wp
	549	H = rho_cp * shf
[1500]	550
	551	IF ( humidity ) THEN
	552	LE = rho_l * l_v * qsws
	553	ELSE
	554	LE = 0.0_wp
	555	ENDIF
	556
[1496]	557	LE_veg = 0.0_wp
	558	LE_soil = LE
	559	LE_liq = 0.0_wp
	560
	561	r_a = 50.0_wp
	562	r_canopy = 0.0_wp
	563	r_soil = 0.0_wp
	564	r_soil_min = 50.0_wp
	565	r_s = 110.0_wp
	566	r_s_min = min_canopy_resistance
	567
	568	!
	569	!-- Allocate 3D soil model arrays
	570	ALLOCATE ( root_fr(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	571	ALLOCATE ( lambda_h(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	572	ALLOCATE ( rhoC_total(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	573
	574	lambda_h = 0.0_wp
	575	!
	576	!-- If required, allocate humidity-related variables for the soil model
	577	IF ( humidity ) THEN
	578	ALLOCATE ( lambda_w(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	579	ALLOCATE ( gamma_w(0:soil_layers-1,nysg:nyng,nxlg:nxrg) )
	580
	581	lambda_w = 0.0_wp
	582	ENDIF
	583
	584	!
	585	!-- Calculate grid spacings. Temperature and moisture are defined at
	586	!-- the center of the soil layers, whereas gradients/fluxes are defined
	587	!-- at the edges (_stag)
	588	dz_soil_stag(0) = soil_level(0)
	589
	590	DO k = 1, soil_layers-1
	591	dz_soil_stag(k) = soil_level(k) - soil_level(k-1)
	592	ENDDO
	593
	594	DO k = 0, soil_layers-2
	595	dz_soil(k) = 0.5 * (dz_soil_stag(k+1) + dz_soil_stag(k))
	596	ENDDO
	597	dz_soil(soil_layers-1) = dz_soil_stag(soil_layers-1)
	598
	599	ddz_soil = 1.0 / dz_soil
	600	ddz_soil_stag = 1.0 / dz_soil_stag
	601	!
	602	!-- Initialize soil
	603	IF ( soil_type .NE. 0 ) THEN
	604	alpha_VG = soil_pars(0,soil_type)
	605	l_VG = soil_pars(1,soil_type)
	606	n_VG = soil_pars(2,soil_type)
	607	gamma_w_sat = soil_pars(3,soil_type)
	608	m_sat = m_soil_pars(0,soil_type)
	609	m_fc = m_soil_pars(1,soil_type)
	610	m_wilt = m_soil_pars(2,soil_type)
	611	m_res = m_soil_pars(3,soil_type)
	612	ELSE
	613	alpha_VG = alpha_VanGenuchten
	614	l_VG = l_VanGenuchten
	615	n_VG = n_VanGenuchten
	616	gamma_w_sat = hydraulic_conductivity
	617	m_sat = saturation_moisture
	618	m_fc = field_capacity
	619	m_wilt = wilting_point
	620	m_res = residual_moisture
	621	ENDIF
	622
	623	!
	624	!-- Map user settings of T and q for each soil layer
	625	!-- (make sure that the soil moisture does not drop below the permanent
	626	!-- wilting point) -> problems with devision by zero)
	627	DO k = 0, soil_layers-1
	628	T_soil(k,:,:) = soil_temperature(k)
	629	m_soil(k,:,:) = MAX(soil_moisture(k),m_wilt(:,:))
	630	ENDDO
	631	T_soil(soil_layers,:,:) = soil_temperature(soil_layers)
	632
	633
	634	exn = ( surface_pressure / 1000.0_wp )**0.286_wp
	635	T_0 = pt_surface * exn
	636
	637	T_soil_p = T_soil
	638	m_soil_p = m_soil
	639
	640	!
	641	!-- Calculate saturation soil heat conductivity
	642	lambda_h_sat(:,:) = lambda_h_sm ** (1.0_wp - m_sat(:,:)) * &
	643	lambda_h_water ** m_sat(:,:)
	644
	645	!
	646	!-- Initialize vegetation
	647	IF ( veg_type .NE. 0 ) THEN
	648
	649	r_s_min = veg_pars(0,veg_type)
	650	LAI = veg_pars(1,veg_type)
	651	c_veg = veg_pars(2,veg_type)
	652	gD = veg_pars(3,veg_type)
	653	lambda_skin_s = skin_pars(0,veg_type)
	654	lambda_skin_u = skin_pars(1,veg_type)
	655	f_SW_in = skin_pars(2,veg_type)
	656	z0 = roughness_par(0,veg_type)
	657	z0h = roughness_par(1,veg_type)
	658
	659
	660	DO k = 0, soil_layers-1
	661	root_fr(k,:,:) = root_distribution(k,veg_type)
	662	ENDDO
	663
	664	ELSE
	665
	666	DO k = 0, soil_layers-1
	667	root_fr(k,:,:) = root_fraction(k)
	668	ENDDO
	669
	670	ENDIF
	671
	672	!
	673	!-- Possibly do user-defined actions (e.g. define heterogeneous land surface)
	674	CALL user_init_land_surface
	675
	676	!
	677	!-- Set artifical values for ts and us so that r_a has its initial value for
	678	!-- the first time step
	679	DO i = nxlg, nxrg
	680	DO j = nysg, nyng
	681	k = nzb_s_inner(j,i)
[1500]	682	!
	683	!-- Assure that r_a cannot be zero at model start
	684	IF ( pt(k+1,j,i) == pt(k,j,i) ) pt(k+1,j,i) = pt(k+1,j,i) + 1.0E-10_wp
	685
[1496]	686	us(j,i) = 0.1_wp
	687	ts(j,i) = (pt(k+1,j,i) - pt(k,j,i)) / r_a(j,i)
	688	shf(j,i) = - us(j,i) * ts(j,i)
	689	ENDDO
	690	ENDDO
	691
	692	!
	693	!-- Calculate humidity at the surface
	694	IF ( humidity ) THEN
	695	CALL calc_q0
	696	ENDIF
	697
	698	RETURN
	699
	700	END SUBROUTINE init_lsm
	701
	702
	703
	704	!------------------------------------------------------------------------------!
	705	! Description:
	706	! ------------
	707	!
	708	!------------------------------------------------------------------------------!
	709	SUBROUTINE lsm_energy_balance
	710
	711
	712	IMPLICIT NONE
	713
	714	INTEGER(iwp) :: i !: running index
	715	INTEGER(iwp) :: j !: running index
	716	INTEGER(iwp) :: k, ks !: running index
	717
	718	REAL(wp) :: f1, & !: resistance correction term 1
	719	f2, & !: resistance correction term 2
	720	f3, & !: resistance correction term 3
	721	m_min, & !: minimum soil moisture
	722	T_1, & !: actual temperature at first grid point
	723	e, & !: water vapour pressure
	724	e_s, & !: water vapour saturation pressure
	725	e_s_dT, & !: derivate of e_s with respect to T
	726	tend, & !: tendency
	727	dq_s_dT, & !: derivate of q_s with respect to T
	728	coef_1, & !: coef. for prognostic equation
	729	coef_2, & !: coef. for prognostic equation
	730	f_LE, & !: factor for LE
	731	f_LE_veg, & !: factor for LE_veg
	732	f_LE_soil, & !: factor for LE_soil
	733	f_LE_liq, & !: factor for LE_liq
	734	f_H, & !: factor for H
	735	lambda_skin, & !: Current value of lambda_skin
	736	m_liq_max !: maxmimum value of the liquid water reservoir
	737
	738	!
	739	!-- Calculate the exner function for the current time step
	740	exn = ( surface_pressure / 1000.0_wp )**0.286_wp
	741
	742
	743	DO i = nxlg, nxrg
	744	DO j = nysg, nyng
[1500]	745	k = nzb_s_inner(j,i)
[1496]	746
	747	!
	748	!-- Set lambda_skin according to stratification
	749	IF ( rif(j,i) >= 0.0_wp ) THEN
	750	lambda_skin = lambda_skin_s(j,i)
	751	ELSE
	752	lambda_skin = lambda_skin_u(j,i)
	753	ENDIF
[1500]	754
[1496]	755	!
[1500]	756	!-- First step: calculate aerodyamic resistance. As pt, us, ts
	757	!-- are not available for the prognostic time step, data from the last
	758	!-- time step is used here. Note that this formulation is the
	759	!-- equivalent to the ECMWF formulation using drag coefficients
	760	r_a(j,i) = (pt(k+1,j,i) - pt(k,j,i)) / (ts(j,i) * us(j,i) + 1.0E-20)
[1496]	761
	762	!
	763	!-- Second step: calculate canopy resistance r_canopy
	764	!-- f1-f3 here are defined as 1/f1-f3 as in ECMWF documentation
	765
	766	!-- f1: correction for incoming shortwave radiation
	767	f1 = MIN(1.0_wp, ( 0.004_wp * SW_in(j,i) + 0.05_wp ) / &
	768	(0.81_wp * (0.004_wp * SW_in(j,i) + 1.0_wp) ) )
	769
	770	!
	771	!-- f2: correction for soil moisture f2=0 for very dry soil
	772	m_total = 0.0_wp
	773	DO ks = 0, soil_layers-1
	774	m_total = m_total + root_fr(ks,j,i) * m_soil(ks,j,i)
	775	ENDDO
	776
	777	IF ( m_total .GT. m_wilt(j,i) .AND. m_total .LE. m_fc(j,i) ) THEN
	778	f2 = ( m_total - m_wilt(j,i) ) / (m_fc(j,i) - m_wilt(j,i) )
	779	ELSE
	780	f2 = 1.0E-20_wp
	781	ENDIF
	782
	783	!
	784	!-- Calculate water vapour pressure at saturation
	785	!-- (T_0 should be replaced by liquid water temp?!)
	786	e_s = 0.01 * 610.78_wp * EXP( 17.269_wp * ( T_0(j,i) - 273.16_wp )&
	787	/ ( T_0(j,i) - 35.86_wp ) )
	788
	789	!
	790	!-- f3: correction for vapour pressure deficit
	791	IF ( gD(j,i) .NE. 0.0_wp ) THEN
	792	!
	793	!-- Calculate vapour pressure
	794	e = q_p(k+1,j,i) * surface_pressure / 0.622
	795	f3 = EXP ( -gD(j,i) * (e_s - e) )
	796	ELSE
	797	f3 = 1.0_wp
	798	ENDIF
	799
	800	!
	801	!-- To do: check for very dry soil -> r_canopy goes to infinity
	802	r_canopy(j,i) = r_s_min(j,i) / (LAI(j,i) * f1 * f2 * f3 + 1.0E-20)
	803
	804	!
	805	!-- Third step: calculate bare soil resistance r_soil
	806	m_min = c_veg(j,i) * m_wilt(j,i) + (1.0_wp - c_veg(j,i)) * &
	807	m_res(j,i)
	808
	809	f2 = ( m_soil(0,j,i) - m_min ) / ( m_fc(j,i) - m_min )
	810	f2 = MAX(f2,1.0E-20)
	811
	812	r_soil(j,i) = r_soil_min(j,i) / f2
	813
	814	!
	815	!-- Calculate fraction of liquid water reservoir
	816	m_liq_max = m_max_depth * LAI(j,i)
	817	c_liq(j,i) = MIN(1.0, m_liq(j,i)/m_liq_max)
	818
	819	q_s = 0.622_wp * e_s / surface_pressure
[1500]	820
	821	!
	822	!-- In case of dew fall, set resistances to zero.
	823	!-- To do: what does that physically reasoning behind this?
	824	IF ( humidity ) THEN
	825	IF ( q_s .LE. q_p(k+1,j,i) ) THEN
	826	r_canopy(j,i) = 0.0_wp
	827	r_soil(j,i) = 0.0_wp
	828	ENDIF
[1496]	829	ENDIF
	830
	831
	832	!
	833	!-- Calculate coefficients for the total evapotranspiration
	834	f_LE_veg = rho_lv * c_veg(j,i) * (1.0 - c_liq(j,i)) / (r_a(j,i) &
	835	+ r_canopy(j,i))
	836	f_LE_soil = rho_lv * (1.0 - c_veg(j,i)) / (r_a(j,i) + r_soil(j,i))
	837	f_LE_liq = rho_lv * c_veg(j,i) * c_liq(j,i) / r_a(j,i)
	838
	839
[1500]	840	!
	841	!-- If soil moisture is below wilting point, plants do no longer
	842	!-- transpirate.
	843	IF ( m_soil(k,j,i) .LT. m_wilt(j,i) ) THEN
	844	f_LE_veg = 0.0
	845	ENDIF
[1496]	846
	847	f_H = rho_cp / r_a(j,i)
	848	f_LE = f_LE_veg + f_LE_soil + f_LE_liq
	849
	850	!
	851	!-- Calculate derivative of q_s for Taylor series expansion
	852	e_s_dT = e_s * ( 17.269_wp / (T_0(j,i) - 35.86_wp) - &
	853	17.269_wp*(T_0(j,i) - 273.16_wp) / (T_0(j,i) &
	854	- 35.86_wp)**2 )
	855
	856	dq_s_dT = 0.622_wp * e_s_dT / surface_pressure
	857
	858	T_1 = pt_p(k+1,j,i) * exn
	859
	860	!
	861	!-- Add LW up so that it can be removed in prognostic equation
	862	Rn(j,i) = Rn(j,i) + sigma_SB * T_0(j,i) ** 4
	863
[1500]	864	IF ( humidity ) THEN
	865
[1496]	866	!
[1500]	867	!-- Numerator of the prognostic equation
	868	coef_1 = Rn(j,i) + 3.0_wp * sigma_SB * T_0(j,i) ** 4 + f_H &
	869	/ exn * T_1 + f_LE * ( q_p(k+1,j,i) - q_s + dq_s_dT &
	870	* T_0(j,i) ) + lambda_skin * T_soil(0,j,i)
[1496]	871
	872	!
[1500]	873	!-- Denominator of the prognostic equation
	874	coef_2 = 4.0_wp * sigma_SB * T_0(j,i) ** 3 + f_LE * dq_s_dT &
	875	+ lambda_skin + f_H / exn
[1496]	876
[1500]	877	ELSE
	878
	879	!
	880	!-- Numerator of the prognostic equation
	881	coef_1 = Rn(j,i) + 3.0_wp * sigma_SB * T_0(j,i) ** 4 + f_H / &
	882	exn * T_1 + lambda_skin * T_soil(0,j,i)
	883
	884	!
	885	!-- Denominator of the prognostic equation
	886	coef_2 = 4.0_wp * sigma_SB * T_0(j,i) ** 3 &
	887	+ lambda_skin + f_H / exn
	888
	889	ENDIF
	890
[1496]	891	tend = 0.0_wp
	892
	893	!
	894	!-- Implicit solution when the skin layer has no heat capacity,
	895	!-- otherwise use RK3 scheme.
	896	T_0_p(j,i) = ( coef_1 * dt_3d * tsc(2) + C_skin * T_0(j,i) ) / &
	897	( C_skin + coef_2 * dt_3d * tsc(2) )
	898
	899	!
	900	!-- Add RK3 term
	901	T_0_p(j,i) = T_0_p(j,i) + dt_3d * tsc(3) * tT_soil_m(0,j,i)
	902
	903	!
	904	!-- Calculate true tendency
	905	tend = (T_0_p(j,i) - T_0(j,i) - tsc(3) * tT_0_m(j,i)) / (dt_3d &
	906	* tsc(2))
	907
	908	!
	909	!-- Calculate T_0 tendencies for the next Runge-Kutta step
	910	IF ( timestep_scheme(1:5) == 'runge' ) THEN
	911	IF ( intermediate_timestep_count == 1 ) THEN
	912	tT_0_m(j,i) = tend
	913	ELSEIF ( intermediate_timestep_count < &
	914	intermediate_timestep_count_max ) THEN
	915	tT_0_m(j,i) = -9.5625_wp * tend + 5.3125_wp * tT_0_m(j,i)
	916	ENDIF
	917	ENDIF
	918
	919	pt_p(k,j,i) = T_0_p(j,i) / exn
	920	!
	921	!-- Calculate fluxes
	922	Rn(j,i) = Rn(j,i) + 3.0_wp * sigma_SB * T_0(j,i)**4 &
	923	- 4.0_wp * sigma_SB * T_0(j,i)*3 T_0_p(j,i)
	924	G(j,i) = lambda_skin * (T_0_p(j,i) - T_soil(0,j,i))
	925	H(j,i) = - f_H * ( pt_p(k+1,j,i) - pt_p(k,j,i) )
	926
[1500]	927	IF ( humidity ) THEN
	928	LE(j,i) = - f_LE * ( q_p(k+1,j,i) - q_s + dq_s_dT &
	929	* T_0(j,i) - dq_s_dT * T_0_p(j,i) )
[1496]	930
[1500]	931	LE_veg(j,i) = - f_LE_veg * ( q_p(k+1,j,i) - q_s + dq_s_dT &
	932	* T_0(j,i) - dq_s_dT * T_0_p(j,i) )
	933	LE_soil(j,i) = - f_LE_soil * ( q_p(k+1,j,i) - q_s + dq_s_dT &
	934	* T_0(j,i) - dq_s_dT * T_0_p(j,i) )
	935	LE_liq(j,i) = - f_LE_liq * ( q_p(k+1,j,i) - q_s + dq_s_dT &
	936	* T_0(j,i) - dq_s_dT * T_0_p(j,i) )
	937	ENDIF
[1496]	938
	939	! IF ( i == 1 .AND. j == 1 ) THEN
	940	! PRINT*, "Rn", Rn(j,i)
	941	! PRINT*, "H", H(j,i)
	942	! PRINT*, "LE", LE(j,i)
	943	! PRINT*, "LE_liq", LE_liq(j,i)
	944	! PRINT*, "LE_veg", LE_veg(j,i)
	945	! PRINT*, "LE_soil", LE_soil(j,i)
	946	! PRINT*, "G", G(j,i)
	947	! ENDIF
	948
[1500]	949	!
	950	!-- Calculate the true surface resistance
[1496]	951	IF ( LE(j,i) .EQ. 0.0 ) THEN
	952	r_s(j,i) = 1.0E10
	953	ELSE
	954	r_s(j,i) = - rho_lv * ( q_p(k+1,j,i) - q_s + dq_s_dT * T_0(j,i)&
	955	- dq_s_dT * T_0_p(j,i) ) / LE(j,i) - r_a(j,i)
	956	ENDIF
	957
	958	!
[1500]	959	!-- Calculate fluxes in the atmosphere
	960	shf(j,i) = H(j,i) / rho_cp
	961
	962	!
[1496]	963	!-- Calculate change in liquid water reservoir due to dew fall or
[1500]	964	!-- evaporation of liquid water
	965	IF ( humidity ) THEN
[1496]	966	!
[1500]	967	!-- If precipitation is activated, add rain water to LE_liq.
	968	!-- precipitation_rate is given in mm.
	969	IF ( precipitation ) THEN
	970	LE_liq(j,i) = LE_liq(j,i) + precipitation_rate(j,i) &
	971	* 0.001_wp * rho_l * l_v
[1496]	972	ENDIF
[1500]	973	!
	974	!-- If the air is saturated, check the reservoir water level
	975	IF ( q_s .LE. q_p(k+1,j,i)) THEN
	976	!
	977	!-- Check if reservoir is full (avoid values > m_liq_max)
	978	!-- In that case, LE_liq goes to LE_soil. In this case
	979	!-- LE_veg is zero anyway (because c_liq = 1), so that tend is
	980	!-- zero and no further check is needed
	981	IF ( m_liq(j,i) .EQ. m_liq_max ) THEN
	982	LE_soil(j,i) = LE_soil(j,i) + LE_liq(j,i)
	983	LE_liq(j,i) = 0.0_wp
	984	ENDIF
[1496]	985
	986	!
[1500]	987	!-- In case LE_veg becomes negative (unphysical behavior), let
	988	!-- the water enter the liquid water reservoir as dew on the
	989	!-- plant
	990	IF ( LE_veg(j,i) .LT. 0.0_wp ) THEN
	991	LE_liq(j,i) = LE_liq(j,i) + LE_veg(j,i)
	992	LE_veg(j,i) = 0.0_wp
	993	ENDIF
	994	ENDIF
[1496]	995
[1500]	996	tend = - LE_liq(j,i) * drho_l_lv
[1496]	997
[1500]	998	m_liq_p(j,i) = m_liq(j,i) + dt_3d * ( tsc(2) * tend &
[1496]	999	+ tsc(3) * tm_liq_m(j,i) )
	1000
	1001	!
[1500]	1002	!-- Check if reservoir is overfull -> reduce to maximum
	1003	!-- (conservation of water is violated here)
	1004	m_liq_p(j,i) = MIN(m_liq_p(j,i),m_liq_max)
[1496]	1005
	1006	!
[1500]	1007	!-- Check if reservoir is empty (avoid values < 0.0)
	1008	!-- (conservation of water is violated here)
	1009	m_liq_p(j,i) = MAX(m_liq_p(j,i),0.0_wp)
[1496]	1010
	1011
	1012	!
[1500]	1013	!-- Calculate m_liq tendencies for the next Runge-Kutta step
	1014	IF ( timestep_scheme(1:5) == 'runge' ) THEN
	1015	IF ( intermediate_timestep_count == 1 ) THEN
	1016	tm_liq_m(j,i) = tend
	1017	ELSEIF ( intermediate_timestep_count < &
	1018	intermediate_timestep_count_max ) THEN
	1019	tm_liq_m(j,i) = -9.5625_wp * tend + 5.3125_wp &
	1020	* tm_liq_m(j,i)
	1021	ENDIF
[1496]	1022	ENDIF
	1023
	1024	!
[1500]	1025	!-- Calculate moisture flux in the atmosphere
	1026	qsws(j,i) = LE(j,i) / rho_lv
[1496]	1027
[1500]	1028	ENDIF
	1029
[1496]	1030	ENDDO
[1500]	1031	ENDDO
[1496]	1032
	1033
	1034
	1035	END SUBROUTINE lsm_energy_balance
	1036
	1037
	1038	!------------------------------------------------------------------------------!
	1039	! Description:
	1040	! ------------
	1041	!
	1042	!------------------------------------------------------------------------------!
	1043	SUBROUTINE lsm_soil_model
	1044
	1045
	1046	IMPLICIT NONE
	1047
	1048	INTEGER(iwp) :: i !: running index
	1049	INTEGER(iwp) :: j !: running index
	1050	INTEGER(iwp) :: k !: running index
	1051
	1052	REAL(wp) :: h_VG !: Van Genuchten coef. h
	1053
	1054	REAL(wp), DIMENSION(0:soil_layers-1) :: gamma_temp, & !: temp. gamma
	1055	lambda_temp, & !: temp. lambda
	1056	tend !: tendency
	1057
	1058	DO i = nxlg, nxrg
	1059	DO j = nysg, nyng
	1060	DO k = 0, soil_layers-1
	1061	!
	1062	!-- Calculate volumetric heat capacity of the soil, taking into
	1063	!-- account water content
	1064	rhoC_total(k,j,i) = (rhoC_soil * (1.0 - m_sat(j,i)) &
	1065	+ rhoC_water * m_soil(k,j,i))
	1066
	1067	!
	1068	!-- Calculate soil heat conductivity at the center of the soil
	1069	!-- layers
	1070	Ke = 1.0 + LOG10(MAX(0.1,m_soil(k,j,i) / m_sat(j,i)))
	1071	lambda_temp(k) = Ke * (lambda_h_sat(j,i) + lambda_h_dry) + &
	1072	lambda_h_dry
	1073
	1074	ENDDO
	1075
	1076	!
	1077	!-- Calculate soil heat conductivity (lambda_h) at the _stag level
	1078	!-- using linear interpolation
	1079	DO k = 0, soil_layers-2
	1080
	1081	lambda_h(k,j,i) = lambda_temp(k) + &
	1082	( lambda_temp(k+1) - lambda_temp(k) ) &
	1083	* 0.5 * dz_soil_stag(k) * ddz_soil(k+1)
	1084
	1085	ENDDO
	1086	lambda_h(soil_layers-1,j,i) = lambda_temp(soil_layers-1)
	1087
	1088	!
	1089	!-- Prognostic equation for soil temperature T_soil
	1090	tend(:) = 0.0_wp
	1091	tend(0) = (1.0/rhoC_total(0,j,i)) * &
	1092	( lambda_h(0,j,i) * ( T_soil(1,j,i) - T_soil(0,j,i) ) &
	1093	* ddz_soil(0) + G(j,i) ) * ddz_soil_stag(0)
	1094
	1095	DO k = 1, soil_layers-1
	1096	tend(k) = (1.0/rhoC_total(k,j,i)) &
	1097	* ( lambda_h(k,j,i) &
	1098	* ( T_soil(k+1,j,i) - T_soil(k,j,i) ) &
	1099	* ddz_soil(k) &
	1100	- lambda_h(k-1,j,i) &
	1101	* ( T_soil(k,j,i) - T_soil(k-1,j,i) ) &
	1102	* ddz_soil(k-1) &
	1103	) * ddz_soil_stag(k)
	1104	ENDDO
	1105
	1106	T_soil_p(0:soil_layers-1,j,i) = T_soil(0:soil_layers-1,j,i) &
	1107	+ dt_3d * ( tsc(2) &
	1108	* tend(:) + tsc(3) &
	1109	* tT_soil_m(:,j,i) )
	1110
	1111	!
	1112	!-- Calculate T_soil tendencies for the next Runge-Kutta step
	1113	IF ( timestep_scheme(1:5) == 'runge' ) THEN
	1114	IF ( intermediate_timestep_count == 1 ) THEN
	1115	DO k = 0, soil_layers-1
	1116	tT_soil_m(k,j,i) = tend(k)
	1117	ENDDO
	1118	ELSEIF ( intermediate_timestep_count < &
	1119	intermediate_timestep_count_max ) THEN
	1120	DO k = 0, soil_layers-1
	1121	tT_soil_m(k,j,i) = -9.5625_wp * tend(k) + 5.3125_wp &
	1122	* tT_soil_m(k,j,i)
	1123	ENDDO
	1124	ENDIF
	1125	ENDIF
	1126
	1127
	1128	DO k = 0, soil_layers-1
	1129	!
	1130	!-- Calculate soil diffusivity at the center of the soil layers
	1131	lambda_temp(k) = (- b_CH * gamma_w_sat(j,i) * psi_sat &
	1132	/ m_sat(j,i) ) * ( MAX(m_soil(k,j,i), &
	1133	m_wilt(j,i)) / m_sat(j,i) )**(b_CH + 2.0_wp)
	1134
	1135	!
	1136	!-- Calculate the hydraulic conductivity after Van Genuchten (1980)
	1137	h_VG = ( ( (m_res(j,i) - m_sat(j,i)) / ( m_res(j,i) - &
	1138	MAX(m_soil(k,j,i),m_wilt(j,i)) ) )**(n_VG(j,i) &
	1139	/ (n_VG(j,i)-1.0_wp)) - 1.0_wp &
	1140	)**(1.0_wp/n_VG(j,i)) / alpha_VG(j,i)
	1141
	1142	gamma_temp(k) = gamma_w_sat(j,i) * ( ( (1.0_wp + &
	1143	(alpha_VG(j,i)h_VG)n_VG(j,i))*(1.0_wp &
	1144	-1.0_wp/n_VG(j,i)) - (alpha_VG(j,i)*h_VG &
	1145	)(n_VG(j,i)-1.0_wp))2 ) &
	1146	/ ( (1.0_wp + (alpha_VG(j,i)h_VG)*n_VG(j,i) &
	1147	)*((1.0_wp - 1.0_wp/n_VG(j,i))(l_VG(j,i) &
	1148	+ 2.0)) )
	1149
	1150	ENDDO
	1151
	1152
	1153	IF ( humidity ) THEN
	1154	!
	1155	!-- Calculate soil diffusivity (lambda_w) at the _stag level
	1156	!-- using linear interpolation
	1157	DO k = 0, soil_layers-2
	1158
	1159	lambda_w(k,j,i) = lambda_temp(k) + &
	1160	( lambda_temp(k+1) - lambda_temp(k) ) &
	1161	* 0.5 * dz_soil_stag(k) * ddz_soil(k+1)
	1162	gamma_w(k,j,i) = gamma_temp(k) + &
	1163	( gamma_temp(k+1) - gamma_temp(k) ) &
	1164	* 0.5 * dz_soil_stag(k) * ddz_soil(k+1)
	1165
	1166	ENDDO
	1167
	1168	!
	1169	!
	1170	!-- In case of a closed bottom (= water content is conserved), set
	1171	!-- hydraulic conductivity to zero to that no water will be lost
	1172	!-- in the bottom layer.
	1173	IF ( conserve_water_content ) THEN
	1174	gamma_w(soil_layers-1,j,i) = 0.0_wp
	1175	ELSE
	1176	gamma_w(soil_layers-1,j,i) = lambda_temp(soil_layers-1)
	1177	ENDIF
	1178
	1179	!-- The root extraction (= root_extr * LE_veg / (rho_l * l_v))
	1180	!-- ensures the mass conservation for water. The transpiration of
	1181	!-- plants equals the cumulative withdrawals by the roots in the
	1182	!-- soil. The scheme takes into account the availability of water
	1183	!-- in the soil layers as well as the root fraction in the
	1184	!-- respective layer
	1185
	1186	!
	1187	!-- Calculate the root extraction (ECMWF 7.69, with some
	1188	!-- modifications)
	1189	m_total = 0.0_wp
	1190	DO k = 0, soil_layers-1
	1191	m_total = m_total + root_fr(k,j,i) * m_soil(k,j,i) * &
	1192	dz_soil_stag(k)
	1193
	1194	ENDDO
	1195
	1196	!
	1197	!-- For conservation of mass, the sum of root_extr must be 1
	1198	DO k = 0, soil_layers-1
	1199	root_extr(k) = root_fr(k,j,i) * m_soil(k,j,i) &
	1200	* dz_soil_stag(k) / m_total
	1201	ENDDO
	1202
	1203
	1204	!
	1205	!-- Prognostic equation for soil water content m_soil
	1206	tend(:) = 0.0_wp
	1207	tend(0) = ( lambda_w(0,j,i) * ( m_soil(1,j,i) - m_soil(0,j,i) )&
	1208	* ddz_soil(0) - gamma_w(0,j,i) - ( root_extr(0) &
	1209	* LE_veg(j,i) + LE_soil(j,i) ) * drho_l_lv &
	1210	) * ddz_soil_stag(0)
	1211
	1212	DO k = 1, soil_layers-2
	1213	tend(k) = ( lambda_w(k,j,i) * ( m_soil(k+1,j,i) &
	1214	- m_soil(k,j,i) ) * ddz_soil(k) - gamma_w(k,j,i)&
	1215	- lambda_w(k-1,j,i) * (m_soil(k,j,i) - &
	1216	m_soil(k-1,j,i)) * ddz_soil(k-1) &
	1217	+ gamma_w(k-1,j,i) - (root_extr(k) * LE_veg(j,i)&
	1218	* drho_l_lv) &
	1219	) * ddz_soil_stag(k)
	1220
	1221	ENDDO
	1222	tend(soil_layers-1) = ( - gamma_w(soil_layers-1,j,i) &
	1223	- lambda_w(soil_layers-2,j,i) &
	1224	* (m_soil(soil_layers-1,j,i) &
	1225	- m_soil(soil_layers-2,j,i)) &
	1226	* ddz_soil(soil_layers-2) &
	1227	+ gamma_w(soil_layers-2,j,i) - ( &
	1228	root_extr(soil_layers-1) &
	1229	* LE_veg(j,i) * drho_l_lv ) &
	1230	) * ddz_soil_stag(soil_layers-1)
	1231
	1232	m_soil_p(0:soil_layers-1,j,i) = m_soil(0:soil_layers-1,j,i) &
	1233	+ dt_3d * ( tsc(2) * tend(:) &
	1234	+ tsc(3) * tm_soil_m(:,j,i) )
	1235
	1236	!
	1237	!-- Account for dry soils (find a better solution here!)
	1238	m_soil_p(:,j,i) = MAX(m_soil_p(:,j,i),0.0_wp)
	1239
	1240	!
	1241	!-- Calculate m_soil tendencies for the next Runge-Kutta step
	1242	IF ( timestep_scheme(1:5) == 'runge' ) THEN
	1243	IF ( intermediate_timestep_count == 1 ) THEN
	1244	DO k = 0, soil_layers-1
	1245	tm_soil_m(k,j,i) = tend(k)
	1246	ENDDO
	1247	ELSEIF ( intermediate_timestep_count < &
	1248	intermediate_timestep_count_max ) THEN
	1249	DO k = 0, soil_layers-1
	1250	tm_soil_m(k,j,i) = -9.5625_wp * tend(k) + 5.3125_wp &
	1251	* tm_soil_m(k,j,i)
	1252	ENDDO
	1253	ENDIF
	1254	ENDIF
	1255
	1256	ENDIF
	1257
	1258	ENDDO
	1259	ENDDO
	1260
	1261	!
	1262	!-- Calculate surface specific humidity
	1263	IF ( humidity ) THEN
	1264	CALL calc_q0
	1265	ENDIF
	1266
	1267
	1268	END SUBROUTINE lsm_soil_model
	1269
	1270
	1271	!------------------------------------------------------------------------------!
	1272	! Description:
	1273	! ------------
	1274	!
	1275	!------------------------------------------------------------------------------!
	1276	SUBROUTINE calc_q0
	1277
	1278	IMPLICIT NONE
	1279
	1280	INTEGER :: i !: running index
	1281	INTEGER :: j !: running index
	1282	INTEGER :: k !: running index
	1283	REAL(wp) :: resistance !: aerodynamic and soil resistance term
	1284
	1285	DO i = nxlg, nxrg
	1286	DO j = nysg, nyng
	1287	k = nzb_s_inner(j,i)
	1288	!
	1289	!-- Temporary solution as long as T_0 is prescribed
	1290
	1291	pt_p(k,j,i) = T_0(j,i) / exn
	1292	!
	1293	!-- Calculate water vapour pressure at saturation
	1294	e_s = 0.01_wp * 610.78_wp * EXP( 17.269_wp * ( T_0(j,i) - &
	1295	273.16_wp ) / ( T_0(j,i) - &
	1296	35.86_wp ) )
	1297
	1298	!
	1299	!-- Calculate specific humidity at saturation
	1300	q_s = 0.622_wp * e_s / surface_pressure
	1301
	1302
	1303	resistance = r_a(j,i) / (r_a(j,i) + r_s(j,i))
	1304
	1305	!
	1306	!-- Calculate specific humidity at surface
	1307	q_p(k,j,i) = resistance * q_s + (1.0_wp - resistance) &
	1308	* q_p(k+1,j,i)
	1309
	1310	ENDDO
	1311	ENDDO
	1312
	1313	END SUBROUTINE calc_q0
	1314
	1315
	1316	END MODULE land_surface_model_mod

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