MODULE land_surface_model_mod !--------------------------------------------------------------------------------! ! This file is part of PALM. ! ! PALM is free software: you can redistribute it and/or modify it under the terms ! of the GNU General Public License as published by the Free Software Foundation, ! either version 3 of the License, or (at your option) any later version. ! ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. ! ! You should have received a copy of the GNU General Public License along with ! PALM. If not, see . ! ! Copyright 1997-2014 Leibniz Universitaet Hannover !--------------------------------------------------------------------------------! ! ! Current revisions: ! ----------------- ! ! ! Former revisions: ! ----------------- ! $Id: land_surface_model.f90 1591 2015-05-08 13:57:15Z raasch $ ! Bugfix: REAL constants provided with KIND-attribute in call of ! 1590 2015-05-08 13:56:27Z maronga ! Bugfix: definition of character strings requires same length for all elements ! ! 1585 2015-04-30 07:05:52Z maronga ! Modifications for RRTMG. Changed tables to PARAMETER type. ! ! 1571 2015-03-12 16:12:49Z maronga ! Removed upper-case variable names. Corrected distribution of precipitation to ! the liquid water reservoir and the bare soil fractions. ! ! 1555 2015-03-04 17:44:27Z maronga ! Added output of r_a and r_s ! ! 1553 2015-03-03 17:33:54Z maronga ! Improved better treatment of roughness lengths. Added default soil temperature ! profile ! ! 1551 2015-03-03 14:18:16Z maronga ! Flux calculation is now done in prandtl_fluxes. Added support for data output. ! Vertical indices have been replaced. Restart runs are now possible. Some ! variables have beem renamed. Bugfix in the prognostic equation for the surface ! temperature. Introduced z0_eb and z0h_eb, which overwrite the setting of ! roughness_length and z0_factor. Added Clapp & Hornberger parametrization for ! the hydraulic conductivity. Bugfix for root fraction and extraction ! calculation ! ! intrinsic function MAX and MIN ! ! 1500 2014-12-03 17:42:41Z maronga ! Corrected calculation of aerodynamic resistance (r_a). ! Precipitation is now added to liquid water reservoir using LE_liq. ! Added support for dry runs. ! ! 1496 2014-12-02 17:25:50Z maronga ! Initial revision ! ! ! Description: ! ------------ ! Land surface model, consisting of a solver for the energy balance at the ! surface and a four layer soil scheme. The scheme is similar to the TESSEL ! scheme implemented in the ECMWF IFS model, with modifications according to ! H-TESSEL. The implementation is based on the formulation implemented in the ! DALES and UCLA-LES models. ! ! To do list: ! ----------- ! - Check dewfall parametrization for fog simulations ! - Consider partial absorption of the net shortwave radiation by the surface layer ! - Allow for water surfaces, check performance for bare soils ! - Invert indices (running from -3 to 0. Currently: nzb_soil=0, nzt_soil=3)) ! - Implement surface runoff model (required when performing long-term LES with ! considerable precipitation ! ! Notes: ! ------ ! - No time step criterion is required as long as the soil layers do not become ! too thin !------------------------------------------------------------------------------! USE arrays_3d, & ONLY: pt, pt_p, q_p, qsws, rif, shf, ts, us, z0, z0h USE cloud_parameters, & ONLY: cp, l_d_r, l_v, precipitation_rate, rho_l, r_d, r_v USE control_parameters, & ONLY: cloud_physics, dt_3d, humidity, intermediate_timestep_count, & initializing_actions, intermediate_timestep_count_max, & max_masks, precipitation, pt_surface, rho_surface, & roughness_length, surface_pressure, timestep_scheme, tsc, & z0h_factor, time_since_reference_point USE indices, & ONLY: nbgp, nxlg, nxrg, nyng, nysg, nzb, nzb_s_inner USE kinds USE netcdf_control, & ONLY: dots_label, dots_num, dots_unit USE radiation_model_mod, & ONLY: radiation_scheme, rad_net, rad_sw_in, sigma_sb USE statistics, & ONLY: hom, statistic_regions IMPLICIT NONE ! !-- LSM model constants INTEGER(iwp), PARAMETER :: nzb_soil = 0, & !: bottom of the soil model (to be switched) nzt_soil = 3, & !: top of the soil model (to be switched) nzs = 4 !: number of soil layers (fixed for now) INTEGER(iwp) :: dots_soil = 0 !: starting index for timeseries output INTEGER(iwp), DIMENSION(0:1) :: id_dim_zs_xy, id_dim_zs_xz, id_dim_zs_yz, & id_dim_zs_3d, id_var_zs_xy, & id_var_zs_xz, id_var_zs_yz, id_var_zs_3d INTEGER(iwp), DIMENSION(1:max_masks,0:1) :: id_dim_zs_mask, id_var_zs_mask REAL(wp), PARAMETER :: & b_ch = 6.04_wp, & ! Clapp & Hornberger exponent lambda_h_dry = 0.19_wp, & ! heat conductivity for dry soil lambda_h_sm = 3.44_wp, & ! heat conductivity of the soil matrix lambda_h_water = 0.57_wp, & ! heat conductivity of water psi_sat = -0.388_wp, & ! soil matrix potential at saturation rho_c_soil = 2.19E6_wp, & ! volumetric heat capacity of soil rho_c_water = 4.20E6_wp, & ! volumetric heat capacity of water m_max_depth = 0.0002_wp ! Maximum capacity of the water reservoir (m) ! !-- LSM variables INTEGER(iwp) :: veg_type = 2, & !: vegetation type, 0: user-defined, 1-19: generic (see list) soil_type = 3 !: soil type, 0: user-defined, 1-6: generic (see list) LOGICAL :: conserve_water_content = .TRUE., & !: open or closed bottom surface for the soil model dewfall = .TRUE., & !: allow/inhibit dewfall land_surface = .FALSE. !: flag parameter indicating wheather the lsm is used ! value 9999999.9_wp -> generic available or user-defined value must be set ! otherwise -> no generic variable and user setting is optional REAL(wp) :: alpha_vangenuchten = 9999999.9_wp, & !: NAMELIST alpha_vg canopy_resistance_coefficient = 9999999.9_wp, & !: NAMELIST g_d c_surface = 20000.0_wp, & !: Surface (skin) heat capacity drho_l_lv, & !: (rho_l * l_v)**-1 exn, & !: value of the Exner function e_s = 0.0_wp, & !: saturation water vapour pressure field_capacity = 9999999.9_wp, & !: NAMELIST m_fc f_shortwave_incoming = 9999999.9_wp, & !: NAMELIST f_sw_in hydraulic_conductivity = 9999999.9_wp, & !: NAMELIST gamma_w_sat ke = 0.0_wp, & !: Kersten number lambda_surface_stable = 9999999.9_wp, & !: NAMELIST lambda_surface_s lambda_surface_unstable = 9999999.9_wp, & !: NAMELIST lambda_surface_u leaf_area_index = 9999999.9_wp, & !: NAMELIST lai l_vangenuchten = 9999999.9_wp, & !: NAMELIST l_vg min_canopy_resistance = 9999999.9_wp, & !: NAMELIST r_canopy_min min_soil_resistance = 50.0_wp, & !: NAMELIST r_soil_min m_total = 0.0_wp, & !: weighted total water content of the soil (m3/m3) n_vangenuchten = 9999999.9_wp, & !: NAMELIST n_vg q_s = 0.0_wp, & !: saturation specific humidity residual_moisture = 9999999.9_wp, & !: NAMELIST m_res rho_cp, & !: rho_surface * cp rho_lv, & !: rho * l_v rd_d_rv, & !: r_d / r_v saturation_moisture = 9999999.9_wp, & !: NAMELIST m_sat vegetation_coverage = 9999999.9_wp, & !: NAMELIST c_veg wilting_point = 9999999.9_wp, & !: NAMELIST m_wilt z0_eb = 9999999.9_wp, & !: NAMELIST z0 (lsm_par) z0h_eb = 9999999.9_wp !: NAMELIST z0h (lsm_par) REAL(wp), DIMENSION(nzb_soil:nzt_soil) :: & ddz_soil, & !: 1/dz_soil ddz_soil_stag, & !: 1/dz_soil_stag dz_soil, & !: soil grid spacing (center-center) dz_soil_stag, & !: soil grid spacing (edge-edge) root_extr = 0.0_wp, & !: root extraction root_fraction = (/9999999.9_wp, 9999999.9_wp, & 9999999.9_wp, 9999999.9_wp /), & !: distribution of root surface area to the individual soil layers zs = (/0.07_wp, 0.28_wp, 1.00_wp, 2.89_wp/), & !: soil layer depths (m) soil_moisture = 0.0_wp !: soil moisture content (m3/m3) REAL(wp), DIMENSION(nzb_soil:nzt_soil+1) :: & soil_temperature = (/290.0_wp, 287.0_wp, 285.0_wp, 283.0_wp, & 283.0_wp /) !: soil temperature (K) #if defined( __nopointer ) REAL(wp), DIMENSION(:,:), ALLOCATABLE, TARGET :: t_surface, & !: surface temperature (K) t_surface_p, & !: progn. surface temperature (K) m_liq_eb, & !: liquid water reservoir (m) m_liq_eb_av, & !: liquid water reservoir (m) m_liq_eb_p !: progn. liquid water reservoir (m) #else REAL(wp), DIMENSION(:,:), POINTER :: t_surface, & t_surface_p, & m_liq_eb, & m_liq_eb_p REAL(wp), DIMENSION(:,:), ALLOCATABLE, TARGET :: t_surface_1, t_surface_2, & m_liq_eb_av, & m_liq_eb_1, m_liq_eb_2 #endif ! !-- Temporal tendencies for time stepping REAL(wp), DIMENSION(:,:), ALLOCATABLE :: tt_surface_m, & !: surface temperature tendency (K) tm_liq_eb_m !: liquid water reservoir tendency (m) ! !-- Energy balance variables REAL(wp), DIMENSION(:,:), ALLOCATABLE :: & alpha_vg, & !: coef. of Van Genuchten c_liq, & !: liquid water coverage (of vegetated area) c_liq_av, & !: average of c_liq c_soil_av, & !: average of c_soil c_veg, & !: vegetation coverage c_veg_av, & !: average of c_veg f_sw_in, & !: fraction of absorbed shortwave radiation by the surface layer (not implemented yet) ghf_eb, & !: ground heat flux ghf_eb_av, & !: average of ghf_eb gamma_w_sat, & !: hydraulic conductivity at saturation g_d, & !: coefficient for dependence of r_canopy on water vapour pressure deficit lai, & !: leaf area index lai_av, & !: average of lai lambda_h_sat, & !: heat conductivity for dry soil lambda_surface_s, & !: coupling between surface and soil (depends on vegetation type) lambda_surface_u, & !: coupling between surface and soil (depends on vegetation type) l_vg, & !: coef. of Van Genuchten m_fc, & !: soil moisture at field capacity (m3/m3) m_res, & !: residual soil moisture m_sat, & !: saturation soil moisture (m3/m3) m_wilt, & !: soil moisture at permanent wilting point (m3/m3) n_vg, & !: coef. Van Genuchten qsws_eb, & !: surface flux of latent heat (total) qsws_eb_av, & !: average of qsws_eb qsws_liq_eb, & !: surface flux of latent heat (liquid water portion) qsws_liq_eb_av, & !: average of qsws_liq_eb qsws_soil_eb, & !: surface flux of latent heat (soil portion) qsws_soil_eb_av, & !: average of qsws_soil_eb qsws_veg_eb, & !: surface flux of latent heat (vegetation portion) qsws_veg_eb_av, & !: average of qsws_veg_eb rad_net_l, & !: local copy of rad_net (net radiation at surface) r_a, & !: aerodynamic resistance r_a_av, & !: avergae of r_a r_canopy, & !: canopy resistance r_soil, & !: soil resitance r_soil_min, & !: minimum soil resistance r_s, & !: total surface resistance (combination of r_soil and r_canopy) r_s_av, & !: avergae of r_s r_canopy_min, & !: minimum canopy (stomatal) resistance shf_eb, & !: surface flux of sensible heat shf_eb_av !: average of shf_eb REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: & lambda_h, & !: heat conductivity of soil (?) lambda_w, & !: hydraulic diffusivity of soil (?) gamma_w, & !: hydraulic conductivity of soil (?) rho_c_total !: volumetric heat capacity of the actual soil matrix (?) #if defined( __nopointer ) REAL(wp), DIMENSION(:,:,:), ALLOCATABLE, TARGET :: & t_soil, & !: Soil temperature (K) t_soil_av, & !: Average of t_soil t_soil_p, & !: Prog. soil temperature (K) m_soil, & !: Soil moisture (m3/m3) m_soil_av, & !: Average of m_soil m_soil_p !: Prog. soil moisture (m3/m3) #else REAL(wp), DIMENSION(:,:,:), POINTER :: & t_soil, t_soil_p, & m_soil, m_soil_p REAL(wp), DIMENSION(:,:,:), ALLOCATABLE, TARGET :: & t_soil_av, t_soil_1, t_soil_2, & m_soil_av, m_soil_1, m_soil_2 #endif REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: & tt_soil_m, & !: t_soil storage array tm_soil_m, & !: m_soil storage array root_fr !: root fraction (sum=1) ! !-- Predefined Land surface classes (veg_type) CHARACTER(26), DIMENSION(0:19), PARAMETER :: veg_type_name = (/ & 'user defined ', & ! 0 'crops, mixed farming ', & ! 1 'short grass ', & ! 2 'evergreen needleleaf trees', & ! 3 'deciduous needleleaf trees', & ! 4 'evergreen broadleaf trees ', & ! 5 'deciduous broadleaf trees ', & ! 6 'tall grass ', & ! 7 'desert ', & ! 8 'tundra ', & ! 9 'irrigated crops ', & ! 10 'semidesert ', & ! 11 'ice caps and glaciers ', & ! 12 'bogs and marshes ', & ! 13 'inland water ', & ! 14 'ocean ', & ! 15 'evergreen shrubs ', & ! 16 'deciduous shrubs ', & ! 17 'mixed forest/woodland ', & ! 18 'interrupted forest ' & ! 19 /) ! !-- Soil model classes (soil_type) CHARACTER(12), DIMENSION(0:7), PARAMETER :: soil_type_name = (/ & 'user defined', & ! 0 'coarse ', & ! 1 'medium ', & ! 2 'medium-fine ', & ! 3 'fine ', & ! 4 'very fine ', & ! 5 'organic ', & ! 6 'loamy (CH) ' & ! 7 /) ! !-- Land surface parameters according to the respective classes (veg_type) ! !-- Land surface parameters I !-- r_canopy_min, lai, c_veg, g_d REAL(wp), DIMENSION(0:3,1:19), PARAMETER :: veg_pars = RESHAPE( (/ & 180.0_wp, 3.00_wp, 0.90_wp, 0.00_wp, & ! 1 110.0_wp, 2.00_wp, 0.85_wp, 0.00_wp, & ! 2 500.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 3 500.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 4 175.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 5 240.0_wp, 6.00_wp, 0.99_wp, 0.13_wp, & ! 6 100.0_wp, 2.00_wp, 0.70_wp, 0.00_wp, & ! 7 250.0_wp, 0.05_wp, 0.00_wp, 0.00_wp, & ! 8 80.0_wp, 1.00_wp, 0.50_wp, 0.00_wp, & ! 9 180.0_wp, 3.00_wp, 0.90_wp, 0.00_wp, & ! 10 150.0_wp, 0.50_wp, 0.10_wp, 0.00_wp, & ! 11 0.0_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 12 240.0_wp, 4.00_wp, 0.60_wp, 0.00_wp, & ! 13 0.0_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 14 0.0_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 15 225.0_wp, 3.00_wp, 0.50_wp, 0.00_wp, & ! 16 225.0_wp, 1.50_wp, 0.50_wp, 0.00_wp, & ! 17 250.0_wp, 5.00_wp, 0.90_wp, 0.03_wp, & ! 18 175.0_wp, 2.50_wp, 0.90_wp, 0.03_wp & ! 19 /), (/ 4, 19 /) ) ! !-- Land surface parameters II z0, z0h REAL(wp), DIMENSION(0:1,1:19), PARAMETER :: roughness_par = RESHAPE( (/ & 0.25_wp, 0.25E-2_wp, & ! 1 0.20_wp, 0.20E-2_wp, & ! 2 2.00_wp, 2.00_wp, & ! 3 2.00_wp, 2.00_wp, & ! 4 2.00_wp, 2.00_wp, & ! 5 2.00_wp, 2.00_wp, & ! 6 0.47_wp, 0.47E-2_wp, & ! 7 0.013_wp, 0.013E-2_wp, & ! 8 0.034_wp, 0.034E-2_wp, & ! 9 0.5_wp, 0.50E-2_wp, & ! 10 0.17_wp, 0.17E-2_wp, & ! 11 1.3E-3_wp, 1.3E-4_wp, & ! 12 0.83_wp, 0.83E-2_wp, & ! 13 0.00_wp, 0.00E-2_wp, & ! 14 0.00_wp, 0.00E-2_wp, & ! 15 0.10_wp, 0.10E-2_wp, & ! 16 0.25_wp, 0.25E-2_wp, & ! 17 2.00_wp, 2.00E-2_wp, & ! 18 1.10_wp, 1.10E-2_wp & ! 19 /), (/ 2, 19 /) ) ! !-- Land surface parameters III lambda_surface_s, lambda_surface_u, f_sw_in REAL(wp), DIMENSION(0:2,1:19), PARAMETER :: surface_pars = RESHAPE( (/ & 10.0_wp, 10.0_wp, 0.05_wp, & ! 1 10.0_wp, 10.0_wp, 0.05_wp, & ! 2 20.0_wp, 15.0_wp, 0.03_wp, & ! 3 20.0_wp, 15.0_wp, 0.03_wp, & ! 4 20.0_wp, 15.0_wp, 0.03_wp, & ! 5 20.0_wp, 15.0_wp, 0.03_wp, & ! 6 10.0_wp, 10.0_wp, 0.05_wp, & ! 7 15.0_wp, 15.0_wp, 0.00_wp, & ! 8 10.0_wp, 10.0_wp, 0.05_wp, & ! 9 10.0_wp, 10.0_wp, 0.05_wp, & ! 10 10.0_wp, 10.0_wp, 0.05_wp, & ! 11 58.0_wp, 58.0_wp, 0.00_wp, & ! 12 10.0_wp, 10.0_wp, 0.05_wp, & ! 13 1.0E20_wp, 1.0E20_wp, 0.00_wp, & ! 14 1.0E20_wp, 1.0E20_wp, 0.00_wp, & ! 15 10.0_wp, 10.0_wp, 0.05_wp, & ! 16 10.0_wp, 10.0_wp, 0.05_wp, & ! 17 20.0_wp, 15.0_wp, 0.03_wp, & ! 18 20.0_wp, 15.0_wp, 0.03_wp & ! 19 /), (/ 3, 19 /) ) ! !-- Root distribution (sum = 1) level 1, level 2, level 3, level 4, REAL(wp), DIMENSION(0:3,1:19), PARAMETER :: root_distribution = RESHAPE( (/ & 0.24_wp, 0.41_wp, 0.31_wp, 0.04_wp, & ! 1 0.35_wp, 0.38_wp, 0.23_wp, 0.04_wp, & ! 2 0.26_wp, 0.39_wp, 0.29_wp, 0.06_wp, & ! 3 0.26_wp, 0.38_wp, 0.29_wp, 0.07_wp, & ! 4 0.24_wp, 0.38_wp, 0.31_wp, 0.07_wp, & ! 5 0.25_wp, 0.34_wp, 0.27_wp, 0.14_wp, & ! 6 0.27_wp, 0.27_wp, 0.27_wp, 0.09_wp, & ! 7 1.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 8 0.47_wp, 0.45_wp, 0.08_wp, 0.00_wp, & ! 9 0.24_wp, 0.41_wp, 0.31_wp, 0.04_wp, & ! 10 0.17_wp, 0.31_wp, 0.33_wp, 0.19_wp, & ! 11 0.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 12 0.25_wp, 0.34_wp, 0.27_wp, 0.11_wp, & ! 13 0.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 14 0.00_wp, 0.00_wp, 0.00_wp, 0.00_wp, & ! 15 0.23_wp, 0.36_wp, 0.30_wp, 0.11_wp, & ! 16 0.23_wp, 0.36_wp, 0.30_wp, 0.11_wp, & ! 17 0.19_wp, 0.35_wp, 0.36_wp, 0.10_wp, & ! 18 0.19_wp, 0.35_wp, 0.36_wp, 0.10_wp & ! 19 /), (/ 4, 19 /) ) ! !-- Soil parameters according to the following porosity classes (soil_type) ! !-- Soil parameters I alpha_vg, l_vg, n_vg, gamma_w_sat REAL(wp), DIMENSION(0:3,1:7), PARAMETER :: soil_pars = RESHAPE( (/ & 3.83_wp, 1.250_wp, 1.38_wp, 6.94E-6_wp, & ! 1 3.14_wp, -2.342_wp, 1.28_wp, 1.16E-6_wp, & ! 2 0.83_wp, -0.588_wp, 1.25_wp, 0.26E-6_wp, & ! 3 3.67_wp, -1.977_wp, 1.10_wp, 2.87E-6_wp, & ! 4 2.65_wp, 2.500_wp, 1.10_wp, 1.74E-6_wp, & ! 5 1.30_wp, 0.400_wp, 1.20_wp, 0.93E-6_wp, & ! 6 0.00_wp, 0.00_wp, 0.00_wp, 0.57E-6_wp & ! 7 /), (/ 4, 7 /) ) ! !-- Soil parameters II m_sat, m_fc, m_wilt, m_res REAL(wp), DIMENSION(0:3,1:7), PARAMETER :: m_soil_pars = RESHAPE( (/ & 0.403_wp, 0.244_wp, 0.059_wp, 0.025_wp, & ! 1 0.439_wp, 0.347_wp, 0.151_wp, 0.010_wp, & ! 2 0.430_wp, 0.383_wp, 0.133_wp, 0.010_wp, & ! 3 0.520_wp, 0.448_wp, 0.279_wp, 0.010_wp, & ! 4 0.614_wp, 0.541_wp, 0.335_wp, 0.010_wp, & ! 5 0.766_wp, 0.663_wp, 0.267_wp, 0.010_wp, & ! 6 0.472_wp, 0.323_wp, 0.171_wp, 0.000_wp & ! 7 /), (/ 4, 7 /) ) SAVE PRIVATE ! !-- Public parameters, constants and initial values PUBLIC alpha_vangenuchten, c_surface, canopy_resistance_coefficient, & conserve_water_content, dewfall, field_capacity, & f_shortwave_incoming, hydraulic_conductivity, init_lsm, & init_lsm_arrays, lambda_surface_stable, lambda_surface_unstable, & land_surface, leaf_area_index, lsm_energy_balance, lsm_soil_model, & lsm_swap_timelevel, l_vangenuchten, min_canopy_resistance, & min_soil_resistance, n_vangenuchten, residual_moisture, rho_cp, & rho_lv, root_fraction, saturation_moisture, soil_moisture, & soil_temperature, soil_type, soil_type_name, vegetation_coverage, & veg_type, veg_type_name, wilting_point, z0_eb, z0h_eb ! !-- Public grid and NetCDF variables PUBLIC dots_soil, id_dim_zs_xy, id_dim_zs_xz, id_dim_zs_yz, & id_dim_zs_3d, id_dim_zs_mask, id_var_zs_xy, id_var_zs_xz, & id_var_zs_yz, id_var_zs_3d, id_var_zs_mask, nzb_soil, nzs, nzt_soil,& zs ! !-- Public 2D output variables PUBLIC c_liq, c_liq_av, c_soil_av, c_veg, c_veg_av, ghf_eb, ghf_eb_av, & lai, lai_av, qsws_eb, qsws_eb_av, qsws_liq_eb, qsws_liq_eb_av, & qsws_soil_eb, qsws_soil_eb_av, qsws_veg_eb, qsws_veg_eb_av, & r_a, r_a_av, r_s, r_s_av, shf_eb, shf_eb_av ! !-- Public prognostic variables PUBLIC m_liq_eb, m_liq_eb_av, m_soil, m_soil_av, t_soil, t_soil_av INTERFACE init_lsm MODULE PROCEDURE init_lsm END INTERFACE init_lsm INTERFACE lsm_energy_balance MODULE PROCEDURE lsm_energy_balance END INTERFACE lsm_energy_balance INTERFACE lsm_soil_model MODULE PROCEDURE lsm_soil_model END INTERFACE lsm_soil_model INTERFACE lsm_swap_timelevel MODULE PROCEDURE lsm_swap_timelevel END INTERFACE lsm_swap_timelevel CONTAINS !------------------------------------------------------------------------------! ! Description: ! ------------ !-- Allocate land surface model arrays and define pointers !------------------------------------------------------------------------------! SUBROUTINE init_lsm_arrays IMPLICIT NONE ! !-- Allocate surface and soil temperature / humidity #if defined( __nopointer ) ALLOCATE ( m_liq_eb(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_liq_eb_p(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_soil(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_soil_p(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_surface(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_surface_p(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_soil(nzb_soil:nzt_soil+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_soil_p(nzb_soil:nzt_soil+1,nysg:nyng,nxlg:nxrg) ) #else ALLOCATE ( m_liq_eb_1(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_liq_eb_2(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_soil_1(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_soil_2(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_surface_1(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_surface_2(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_soil_1(nzb_soil:nzt_soil+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( t_soil_2(nzb_soil:nzt_soil+1,nysg:nyng,nxlg:nxrg) ) #endif ! !-- Allocate intermediate timestep arrays ALLOCATE ( tm_liq_eb_m(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( tm_soil_m(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( tt_surface_m(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( tt_soil_m(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ! !-- Allocate 2D vegetation model arrays ALLOCATE ( alpha_vg(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( c_liq(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( c_veg(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( f_sw_in(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( ghf_eb(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( gamma_w_sat(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( g_d(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( lai(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( l_vg(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( lambda_h_sat(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( lambda_surface_u(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( lambda_surface_s(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_fc(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_res(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_sat(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( m_wilt(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( n_vg(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( qsws_eb(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( qsws_soil_eb(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( qsws_liq_eb(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( qsws_veg_eb(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( rad_net_l(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( r_a(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( r_canopy(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( r_soil(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( r_soil_min(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( r_s(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( r_canopy_min(nysg:nyng,nxlg:nxrg) ) ALLOCATE ( shf_eb(nysg:nyng,nxlg:nxrg) ) #if ! defined( __nopointer ) ! !-- Initial assignment of the pointers t_soil => t_soil_1; t_soil_p => t_soil_2 t_surface => t_surface_1; t_surface_p => t_surface_2 m_soil => m_soil_1; m_soil_p => m_soil_2 m_liq_eb => m_liq_eb_1; m_liq_eb_p => m_liq_eb_2 #endif END SUBROUTINE init_lsm_arrays !------------------------------------------------------------------------------! ! Description: ! ------------ !-- Initialization of the land surface model !------------------------------------------------------------------------------! SUBROUTINE init_lsm IMPLICIT NONE INTEGER(iwp) :: i !: running index INTEGER(iwp) :: j !: running index INTEGER(iwp) :: k !: running index ! !-- Calculate Exner function exn = ( surface_pressure / 1000.0_wp )**0.286_wp ! !-- If no cloud physics is used, rho_surface has not been calculated before IF ( .NOT. cloud_physics ) THEN rho_surface = surface_pressure * 100.0_wp / ( r_d * pt_surface * exn ) ENDIF ! !-- Calculate frequently used parameters rho_cp = cp * rho_surface rd_d_rv = r_d / r_v rho_lv = rho_surface * l_v drho_l_lv = 1.0_wp / (rho_l * l_v) ! !-- Set inital values for prognostic quantities tt_surface_m = 0.0_wp tt_soil_m = 0.0_wp tm_liq_eb_m = 0.0_wp c_liq = 0.0_wp ghf_eb = 0.0_wp shf_eb = rho_cp * shf IF ( humidity ) THEN qsws_eb = rho_l * l_v * qsws ELSE qsws_eb = 0.0_wp ENDIF qsws_liq_eb = 0.0_wp qsws_soil_eb = qsws_eb qsws_veg_eb = 0.0_wp r_a = 50.0_wp r_s = 50.0_wp r_canopy = 0.0_wp r_soil = 0.0_wp ! !-- Allocate 3D soil model arrays ALLOCATE ( root_fr(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( lambda_h(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( rho_c_total(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) lambda_h = 0.0_wp ! !-- If required, allocate humidity-related variables for the soil model IF ( humidity ) THEN ALLOCATE ( lambda_w(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) ALLOCATE ( gamma_w(nzb_soil:nzt_soil,nysg:nyng,nxlg:nxrg) ) lambda_w = 0.0_wp ENDIF ! !-- Calculate grid spacings. Temperature and moisture are defined at !-- the center of the soil layers, whereas gradients/fluxes are defined !-- at the edges (_stag) dz_soil_stag(nzb_soil) = zs(nzb_soil) DO k = nzb_soil+1, nzt_soil dz_soil_stag(k) = zs(k) - zs(k-1) ENDDO DO k = nzb_soil, nzt_soil-1 dz_soil(k) = 0.5 * (dz_soil_stag(k+1) + dz_soil_stag(k)) ENDDO dz_soil(nzt_soil) = dz_soil_stag(nzt_soil) ddz_soil = 1.0_wp / dz_soil ddz_soil_stag = 1.0_wp / dz_soil_stag ! !-- Initialize standard soil types. It is possible to overwrite each !-- parameter by setting the respecticy NAMELIST variable to a !-- value /= 9999999.9. IF ( soil_type /= 0 ) THEN IF ( alpha_vangenuchten == 9999999.9_wp ) THEN alpha_vangenuchten = soil_pars(0,soil_type) ENDIF IF ( l_vangenuchten == 9999999.9_wp ) THEN l_vangenuchten = soil_pars(1,soil_type) ENDIF IF ( n_vangenuchten == 9999999.9_wp ) THEN n_vangenuchten = soil_pars(2,soil_type) ENDIF IF ( hydraulic_conductivity == 9999999.9_wp ) THEN hydraulic_conductivity = soil_pars(3,soil_type) ENDIF IF ( saturation_moisture == 9999999.9_wp ) THEN saturation_moisture = m_soil_pars(0,soil_type) ENDIF IF ( field_capacity == 9999999.9_wp ) THEN field_capacity = m_soil_pars(1,soil_type) ENDIF IF ( wilting_point == 9999999.9_wp ) THEN wilting_point = m_soil_pars(2,soil_type) ENDIF IF ( residual_moisture == 9999999.9_wp ) THEN residual_moisture = m_soil_pars(3,soil_type) ENDIF ENDIF alpha_vg = alpha_vangenuchten l_vg = l_vangenuchten n_vg = n_vangenuchten gamma_w_sat = hydraulic_conductivity m_sat = saturation_moisture m_fc = field_capacity m_wilt = wilting_point m_res = residual_moisture r_soil_min = min_soil_resistance ! !-- Initial run actions IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN t_soil = 0.0_wp m_liq_eb = 0.0_wp m_soil = 0.0_wp ! !-- Map user settings of T and q for each soil layer !-- (make sure that the soil moisture does not drop below the permanent !-- wilting point) -> problems with devision by zero) DO k = nzb_soil, nzt_soil t_soil(k,:,:) = soil_temperature(k) m_soil(k,:,:) = MAX(soil_moisture(k),m_wilt(:,:)) soil_moisture(k) = MAX(soil_moisture(k),wilting_point) ENDDO t_soil(nzt_soil+1,:,:) = soil_temperature(nzt_soil+1) ! !-- Calculate surface temperature t_surface = pt_surface * exn ! !-- Set artifical values for ts and us so that r_a has its initial value for !-- the first time step DO i = nxlg, nxrg DO j = nysg, nyng k = nzb_s_inner(j,i) ! !-- Assure that r_a cannot be zero at model start IF ( pt(k+1,j,i) == pt(k,j,i) ) pt(k+1,j,i) = pt(k+1,j,i) & + 1.0E-10_wp us(j,i) = 0.1_wp ts(j,i) = (pt(k+1,j,i) - pt(k,j,i)) / r_a(j,i) shf(j,i) = - us(j,i) * ts(j,i) ENDDO ENDDO ! !-- Actions for restart runs ELSE DO i = nxlg, nxrg DO j = nysg, nyng k = nzb_s_inner(j,i) t_surface(j,i) = pt(k,j,i) * exn ENDDO ENDDO ENDIF ! !-- Calculate saturation soil heat conductivity lambda_h_sat(:,:) = lambda_h_sm ** (1.0_wp - m_sat(:,:)) * & lambda_h_water ** m_sat(:,:) DO k = nzb_soil, nzt_soil root_fr(k,:,:) = root_fraction(k) ENDDO IF ( veg_type /= 0 ) THEN IF ( min_canopy_resistance == 9999999.9_wp ) THEN min_canopy_resistance = veg_pars(0,veg_type) ENDIF IF ( leaf_area_index == 9999999.9_wp ) THEN leaf_area_index = veg_pars(1,veg_type) ENDIF IF ( vegetation_coverage == 9999999.9_wp ) THEN vegetation_coverage = veg_pars(2,veg_type) ENDIF IF ( canopy_resistance_coefficient == 9999999.9_wp ) THEN canopy_resistance_coefficient= veg_pars(3,veg_type) ENDIF IF ( lambda_surface_stable == 9999999.9_wp ) THEN lambda_surface_stable = surface_pars(0,veg_type) ENDIF IF ( lambda_surface_unstable == 9999999.9_wp ) THEN lambda_surface_unstable = surface_pars(1,veg_type) ENDIF IF ( f_shortwave_incoming == 9999999.9_wp ) THEN f_shortwave_incoming = surface_pars(2,veg_type) ENDIF IF ( z0_eb == 9999999.9_wp ) THEN roughness_length = roughness_par(0,veg_type) z0_eb = roughness_par(0,veg_type) ENDIF IF ( z0h_eb == 9999999.9_wp ) THEN z0h_eb = roughness_par(1,veg_type) ENDIF z0h_factor = z0h_eb / z0_eb IF ( ANY( root_fraction == 9999999.9_wp ) ) THEN DO k = nzb_soil, nzt_soil root_fr(k,:,:) = root_distribution(k,veg_type) root_fraction(k) = root_distribution(k,veg_type) ENDDO ENDIF ELSE IF ( z0_eb == 9999999.9_wp ) THEN z0_eb = roughness_length ENDIF IF ( z0h_eb == 9999999.9_wp ) THEN z0h_eb = z0_eb * z0h_factor ENDIF ENDIF ! !-- Initialize vegetation r_canopy_min = min_canopy_resistance lai = leaf_area_index c_veg = vegetation_coverage g_d = canopy_resistance_coefficient lambda_surface_s = lambda_surface_stable lambda_surface_u = lambda_surface_unstable f_sw_in = f_shortwave_incoming z0 = z0_eb z0h = z0h_eb ! !-- Possibly do user-defined actions (e.g. define heterogeneous land surface) CALL user_init_land_surface t_soil_p = t_soil m_soil_p = m_soil m_liq_eb_p = m_liq_eb !-- Store initial profiles of t_soil and m_soil (assuming they are !-- horizontally homogeneous on this PE) hom(nzb_soil:nzt_soil,1,90,:) = SPREAD( t_soil(nzb_soil:nzt_soil, & nysg,nxlg), 2, & statistic_regions+1 ) hom(nzb_soil:nzt_soil,1,92,:) = SPREAD( m_soil(nzb_soil:nzt_soil, & nysg,nxlg), 2, & statistic_regions+1 ) ! !-- Calculate humidity at the surface IF ( humidity ) THEN CALL calc_q_surface ENDIF ! !-- Add timeseries for land surface model dots_label(dots_num+1) = "ghf_eb" dots_label(dots_num+2) = "shf_eb" dots_label(dots_num+3) = "qsws_eb" dots_label(dots_num+4) = "qsws_liq_eb" dots_label(dots_num+5) = "qsws_soil_eb" dots_label(dots_num+6) = "qsws_veg_eb" dots_unit(dots_num+1:dots_num+6) = "W/m2" dots_label(dots_num+7) = "r_a" dots_label(dots_num+8) = "r_s" dots_unit(dots_num+7:dots_num+8) = "s/m" dots_soil = dots_num + 1 dots_num = dots_num + 8 RETURN END SUBROUTINE init_lsm !------------------------------------------------------------------------------! ! Description: ! ------------ ! Solver for the energy balance at the surface. ! ! Note: surface fluxes are calculated in the land surface model, but these are ! not used in the atmospheric code. The fluxes are calculated afterwards in ! prandtl_fluxes using the surface values of temperature and humidity as ! provided by the land surface model. In this way, the fluxes in the land ! surface model are not equal to the ones calculated in prandtl_fluxes !------------------------------------------------------------------------------! SUBROUTINE lsm_energy_balance IMPLICIT NONE INTEGER(iwp) :: i !: running index INTEGER(iwp) :: j !: running index INTEGER(iwp) :: k, ks !: running index REAL(wp) :: f1, & !: resistance correction term 1 f2, & !: resistance correction term 2 f3, & !: resistance correction term 3 m_min, & !: minimum soil moisture T_1, & !: actual temperature at first grid point e, & !: water vapour pressure e_s, & !: water vapour saturation pressure e_s_dt, & !: derivate of e_s with respect to T tend, & !: tendency dq_s_dt, & !: derivate of q_s with respect to T coef_1, & !: coef. for prognostic equation coef_2, & !: coef. for prognostic equation f_qsws, & !: factor for qsws_eb f_qsws_veg, & !: factor for qsws_veg_eb f_qsws_soil, & !: factor for qsws_soil_eb f_qsws_liq, & !: factor for qsws_liq_eb f_shf, & !: factor for shf_eb lambda_surface, & !: Current value of lambda_surface m_liq_eb_max !: maxmimum value of the liq. water reservoir ! !-- Calculate the exner function for the current time step exn = ( surface_pressure / 1000.0_wp )**0.286_wp DO i = nxlg, nxrg DO j = nysg, nyng k = nzb_s_inner(j,i) ! !-- Set lambda_surface according to stratification IF ( rif(j,i) >= 0.0_wp ) THEN lambda_surface = lambda_surface_s(j,i) ELSE lambda_surface = lambda_surface_u(j,i) ENDIF ! !-- First step: calculate aerodyamic resistance. As pt, us, ts !-- are not available for the prognostic time step, data from the last !-- time step is used here. Note that this formulation is the !-- equivalent to the ECMWF formulation using drag coefficients r_a(j,i) = (pt(k+1,j,i) - pt(k,j,i)) / (ts(j,i) * us(j,i) + & 1.0E-20_wp) ! !-- Second step: calculate canopy resistance r_canopy !-- f1-f3 here are defined as 1/f1-f3 as in ECMWF documentation !-- f1: correction for incoming shortwave radiation (stomata close at !-- night) IF ( radiation_scheme /= 'constant' ) THEN f1 = MIN( 1.0_wp, ( 0.004_wp * rad_sw_in(k,j,i) + 0.05_wp ) /& (0.81_wp * (0.004_wp * rad_sw_in(k,j,i) & + 1.0_wp)) ) ELSE f1 = 1.0_wp ENDIF ! !-- f2: correction for soil moisture availability to plants (the !-- integrated soil moisture must thus be considered here) !-- f2 = 0 for very dry soils m_total = 0.0_wp DO ks = nzb_soil, nzt_soil m_total = m_total + root_fr(ks,j,i) & * MAX(m_soil(ks,j,i),m_wilt(j,i)) ENDDO IF ( m_total .GT. m_wilt(j,i) .AND. m_total .LT. m_fc(j,i) ) THEN f2 = ( m_total - m_wilt(j,i) ) / (m_fc(j,i) - m_wilt(j,i) ) ELSEIF ( m_total .GE. m_fc(j,i) ) THEN f2 = 1.0_wp ELSE f2 = 1.0E-20_wp ENDIF ! !-- Calculate water vapour pressure at saturation e_s = 0.01_wp * 610.78_wp * EXP( 17.269_wp * ( t_surface(j,i) & - 273.16_wp ) / ( t_surface(j,i) - 35.86_wp ) ) ! !-- f3: correction for vapour pressure deficit IF ( g_d(j,i) /= 0.0_wp ) THEN ! !-- Calculate vapour pressure e = q_p(k+1,j,i) * surface_pressure / 0.622_wp f3 = EXP ( -g_d(j,i) * (e_s - e) ) ELSE f3 = 1.0_wp ENDIF ! !-- Calculate canopy resistance. In case that c_veg is 0 (bare soils), !-- this calculation is obsolete, as r_canopy is not used below. !-- To do: check for very dry soil -> r_canopy goes to infinity r_canopy(j,i) = r_canopy_min(j,i) / (lai(j,i) * f1 * f2 * f3 & + 1.0E-20_wp) ! !-- Third step: calculate bare soil resistance r_soil. The Clapp & !-- Hornberger parametrization does not consider c_veg. IF ( soil_type /= 7 ) THEN m_min = c_veg(j,i) * m_wilt(j,i) + (1.0_wp - c_veg(j,i)) * & m_res(j,i) ELSE m_min = m_wilt(j,i) ENDIF f2 = ( m_soil(nzb_soil,j,i) - m_min ) / ( m_fc(j,i) - m_min ) f2 = MAX(f2,1.0E-20_wp) f2 = MIN(f2,1.0_wp) r_soil(j,i) = r_soil_min(j,i) / f2 ! !-- Calculate fraction of liquid water reservoir m_liq_eb_max = m_max_depth * lai(j,i) c_liq(j,i) = MIN(1.0_wp, m_liq_eb(j,i) / (m_liq_eb_max+1.0E-20_wp)) ! !-- Calculate saturation specific humidity q_s = 0.622_wp * e_s / surface_pressure ! !-- In case of dewfall, set evapotranspiration to zero !-- All super-saturated water is then removed from the air IF ( humidity .AND. dewfall .AND. q_s .LE. q_p(k+1,j,i) ) THEN r_canopy(j,i) = 0.0_wp r_soil(j,i) = 0.0_wp ENDIF ! !-- Calculate coefficients for the total evapotranspiration f_qsws_veg = rho_lv * c_veg(j,i) * (1.0_wp - c_liq(j,i))/ & (r_a(j,i) + r_canopy(j,i)) f_qsws_soil = rho_lv * (1.0_wp - c_veg(j,i)) / (r_a(j,i) + & r_soil(j,i)) f_qsws_liq = rho_lv * c_veg(j,i) * c_liq(j,i) / r_a(j,i) ! !-- If soil moisture is below wilting point, plants do no longer !-- transpirate. ! IF ( m_soil(k,j,i) .LT. m_wilt(j,i) ) THEN ! f_qsws_veg = 0.0_wp ! ENDIF ! !-- If dewfall is deactivated, vegetation, soil and liquid water !-- reservoir are not allowed to take up water from the super-saturated !-- air. IF ( humidity ) THEN IF ( q_s .LE. q_p(k+1,j,i) ) THEN IF ( .NOT. dewfall ) THEN f_qsws_veg = 0.0_wp f_qsws_soil = 0.0_wp f_qsws_liq = 0.0_wp ENDIF ENDIF ENDIF f_shf = rho_cp / r_a(j,i) f_qsws = f_qsws_veg + f_qsws_soil + f_qsws_liq ! !-- Calculate derivative of q_s for Taylor series expansion e_s_dt = e_s * ( 17.269_wp / (t_surface(j,i) - 35.86_wp) - & 17.269_wp*(t_surface(j,i) - 273.16_wp) & / (t_surface(j,i) - 35.86_wp)**2 ) dq_s_dt = 0.622_wp * e_s_dt / surface_pressure T_1 = pt_p(k+1,j,i) * exn ! !-- Add LW up so that it can be removed in prognostic equation rad_net_l(j,i) = rad_net(j,i) + sigma_sb * t_surface(j,i) ** 4 IF ( humidity ) THEN ! !-- Numerator of the prognostic equation coef_1 = rad_net_l(j,i) + 3.0_wp * sigma_sb * t_surface(j,i) ** 4& + f_shf / exn * T_1 + f_qsws * ( q_p(k+1,j,i) - q_s & + dq_s_dt * t_surface(j,i) ) + lambda_surface & * t_soil(nzb_soil,j,i) ! !-- Denominator of the prognostic equation coef_2 = 4.0_wp * sigma_sb * t_surface(j,i) ** 3 + f_qsws & * dq_s_dt + lambda_surface + f_shf / exn ELSE ! !-- Numerator of the prognostic equation coef_1 = rad_net_l(j,i) + 3.0_wp * sigma_sb * t_surface(j,i) ** 4& + f_shf / exn * T_1 + lambda_surface & * t_soil(nzb_soil,j,i) ! !-- Denominator of the prognostic equation coef_2 = 4.0_wp * sigma_sb * t_surface(j,i) ** 3 & + lambda_surface + f_shf / exn ENDIF tend = 0.0_wp ! !-- Implicit solution when the surface layer has no heat capacity, !-- otherwise use RK3 scheme. t_surface_p(j,i) = ( coef_1 * dt_3d * tsc(2) + c_surface * & t_surface(j,i) ) / ( c_surface + coef_2 * dt_3d& * tsc(2) ) ! !-- Add RK3 term t_surface_p(j,i) = t_surface_p(j,i) + dt_3d * tsc(3) & * tt_surface_m(j,i) ! !-- Calculate true tendency tend = (t_surface_p(j,i) - t_surface(j,i) - dt_3d * tsc(3) & * tt_surface_m(j,i)) / (dt_3d * tsc(2)) ! !-- Calculate t_surface tendencies for the next Runge-Kutta step IF ( timestep_scheme(1:5) == 'runge' ) THEN IF ( intermediate_timestep_count == 1 ) THEN tt_surface_m(j,i) = tend ELSEIF ( intermediate_timestep_count < & intermediate_timestep_count_max ) THEN tt_surface_m(j,i) = -9.5625_wp * tend + 5.3125_wp & * tt_surface_m(j,i) ENDIF ENDIF pt_p(k,j,i) = t_surface_p(j,i) / exn ! !-- Calculate fluxes rad_net_l(j,i) = rad_net_l(j,i) + 3.0_wp * sigma_sb & * t_surface(j,i)**4 - 4.0_wp * sigma_sb & * t_surface(j,i)**3 * t_surface_p(j,i) ghf_eb(j,i) = lambda_surface * (t_surface_p(j,i) & - t_soil(nzb_soil,j,i)) shf_eb(j,i) = - f_shf * ( pt_p(k+1,j,i) - pt_p(k,j,i) ) IF ( humidity ) THEN qsws_eb(j,i) = - f_qsws * ( q_p(k+1,j,i) - q_s + dq_s_dt & * t_surface(j,i) - dq_s_dt * t_surface_p(j,i) ) qsws_veg_eb(j,i) = - f_qsws_veg * ( q_p(k+1,j,i) - q_s & + dq_s_dt * t_surface(j,i) - dq_s_dt & * t_surface_p(j,i) ) qsws_soil_eb(j,i) = - f_qsws_soil * ( q_p(k+1,j,i) - q_s & + dq_s_dt * t_surface(j,i) - dq_s_dt & * t_surface_p(j,i) ) qsws_liq_eb(j,i) = - f_qsws_liq * ( q_p(k+1,j,i) - q_s & + dq_s_dt * t_surface(j,i) - dq_s_dt & * t_surface_p(j,i) ) ENDIF ! !-- Calculate the true surface resistance IF ( qsws_eb(j,i) .EQ. 0.0_wp ) THEN r_s(j,i) = 1.0E10_wp ELSE r_s(j,i) = - rho_lv * ( q_p(k+1,j,i) - q_s + dq_s_dt & * t_surface(j,i) - dq_s_dt * t_surface_p(j,i) ) & / qsws_eb(j,i) - r_a(j,i) ENDIF ! !-- Calculate change in liquid water reservoir due to dew fall or !-- evaporation of liquid water IF ( humidity ) THEN ! !-- If precipitation is activated, add rain water to qsws_liq_eb !-- and qsws_soil_eb according the the vegetation coverage. !-- precipitation_rate is given in mm. IF ( precipitation ) THEN ! !-- Add precipitation to liquid water reservoir, if possible. !-- Otherwise, add the water to bare soil fraction. IF ( m_liq_eb(j,i) .EQ. m_liq_eb_max ) THEN qsws_liq_eb(j,i) = qsws_liq_eb(j,i) & + c_veg(j,i) * precipitation_rate(j,i) & * 0.001_wp * rho_l * l_v ELSE qsws_soil_eb(j,i) = qsws_soil_eb(j,i) & + c_veg(j,i) * precipitation_rate(j,i) & * 0.001_wp * rho_l * l_v ENDIF !-- Add precipitation to bare soil according to the bare soil !-- coverage. qsws_soil_eb(j,i) = qsws_soil_eb(j,i) * (1.0_wp & - c_veg(j,i)) * precipitation_rate(j,i) & * 0.001_wp * rho_l * l_v ENDIF ! !-- If the air is saturated, check the reservoir water level IF ( q_s .LE. q_p(k+1,j,i)) THEN ! !-- Check if reservoir is full (avoid values > m_liq_eb_max) !-- In that case, qsws_liq_eb goes to qsws_soil_eb. In this !-- case qsws_veg_eb is zero anyway (because c_liq = 1), !-- so that tend is zero and no further check is needed IF ( m_liq_eb(j,i) .EQ. m_liq_eb_max ) THEN qsws_soil_eb(j,i) = qsws_soil_eb(j,i) & + qsws_liq_eb(j,i) qsws_liq_eb(j,i) = 0.0_wp ENDIF ! !-- In case qsws_veg_eb becomes negative (unphysical behavior), !-- let the water enter the liquid water reservoir as dew on the !-- plant IF ( qsws_veg_eb(j,i) .LT. 0.0_wp ) THEN qsws_liq_eb(j,i) = qsws_liq_eb(j,i) + qsws_veg_eb(j,i) qsws_veg_eb(j,i) = 0.0_wp ENDIF ENDIF tend = - qsws_liq_eb(j,i) * drho_l_lv m_liq_eb_p(j,i) = m_liq_eb(j,i) + dt_3d * ( tsc(2) * tend & + tsc(3) * tm_liq_eb_m(j,i) ) ! !-- Check if reservoir is overfull -> reduce to maximum !-- (conservation of water is violated here) m_liq_eb_p(j,i) = MIN(m_liq_eb_p(j,i),m_liq_eb_max) ! !-- Check if reservoir is empty (avoid values < 0.0) !-- (conservation of water is violated here) m_liq_eb_p(j,i) = MAX(m_liq_eb_p(j,i),0.0_wp) ! !-- Calculate m_liq_eb tendencies for the next Runge-Kutta step IF ( timestep_scheme(1:5) == 'runge' ) THEN IF ( intermediate_timestep_count == 1 ) THEN tm_liq_eb_m(j,i) = tend ELSEIF ( intermediate_timestep_count < & intermediate_timestep_count_max ) THEN tm_liq_eb_m(j,i) = -9.5625_wp * tend + 5.3125_wp & * tm_liq_eb_m(j,i) ENDIF ENDIF ENDIF ENDDO ENDDO END SUBROUTINE lsm_energy_balance !------------------------------------------------------------------------------! ! Description: ! ------------ ! ! Soil model as part of the land surface model. The model predicts soil ! temperature and water content. !------------------------------------------------------------------------------! SUBROUTINE lsm_soil_model IMPLICIT NONE INTEGER(iwp) :: i !: running index INTEGER(iwp) :: j !: running index INTEGER(iwp) :: k !: running index REAL(wp) :: h_vg !: Van Genuchten coef. h REAL(wp), DIMENSION(nzb_soil:nzt_soil) :: gamma_temp, & !: temp. gamma lambda_temp, & !: temp. lambda tend !: tendency DO i = nxlg, nxrg DO j = nysg, nyng DO k = nzb_soil, nzt_soil ! !-- Calculate volumetric heat capacity of the soil, taking into !-- account water content rho_c_total(k,j,i) = (rho_c_soil * (1.0_wp - m_sat(j,i)) & + rho_c_water * m_soil(k,j,i)) ! !-- Calculate soil heat conductivity at the center of the soil !-- layers ke = 1.0_wp + LOG10(MAX(0.1_wp,m_soil(k,j,i) / m_sat(j,i))) lambda_temp(k) = ke * (lambda_h_sat(j,i) + lambda_h_dry) + & lambda_h_dry ENDDO ! !-- Calculate soil heat conductivity (lambda_h) at the _stag level !-- using linear interpolation DO k = nzb_soil, nzt_soil-1 lambda_h(k,j,i) = lambda_temp(k) + & ( lambda_temp(k+1) - lambda_temp(k) ) & * 0.5 * dz_soil_stag(k) * ddz_soil(k+1) ENDDO lambda_h(nzt_soil,j,i) = lambda_temp(nzt_soil) ! !-- Prognostic equation for soil temperature t_soil tend(:) = 0.0_wp tend(0) = (1.0_wp/rho_c_total(nzb_soil,j,i)) * & ( lambda_h(nzb_soil,j,i) * ( t_soil(nzb_soil+1,j,i) & - t_soil(nzb_soil,j,i) ) * ddz_soil(nzb_soil) & + ghf_eb(j,i) ) * ddz_soil_stag(nzb_soil) DO k = 1, nzt_soil tend(k) = (1.0_wp/rho_c_total(k,j,i)) & * ( lambda_h(k,j,i) & * ( t_soil(k+1,j,i) - t_soil(k,j,i) ) & * ddz_soil(k) & - lambda_h(k-1,j,i) & * ( t_soil(k,j,i) - t_soil(k-1,j,i) ) & * ddz_soil(k-1) & ) * ddz_soil_stag(k) ENDDO t_soil_p(nzb_soil:nzt_soil,j,i) = t_soil(nzb_soil:nzt_soil,j,i) & + dt_3d * ( tsc(2) & * tend(:) + tsc(3) & * tt_soil_m(:,j,i) ) ! !-- Calculate t_soil tendencies for the next Runge-Kutta step IF ( timestep_scheme(1:5) == 'runge' ) THEN IF ( intermediate_timestep_count == 1 ) THEN DO k = nzb_soil, nzt_soil tt_soil_m(k,j,i) = tend(k) ENDDO ELSEIF ( intermediate_timestep_count < & intermediate_timestep_count_max ) THEN DO k = nzb_soil, nzt_soil tt_soil_m(k,j,i) = -9.5625_wp * tend(k) + 5.3125_wp & * tt_soil_m(k,j,i) ENDDO ENDIF ENDIF DO k = nzb_soil, nzt_soil ! !-- Calculate soil diffusivity at the center of the soil layers lambda_temp(k) = (- b_ch * gamma_w_sat(j,i) * psi_sat & / m_sat(j,i) ) * ( MAX(m_soil(k,j,i), & m_wilt(j,i)) / m_sat(j,i) )**(b_ch + 2.0_wp) ! !-- Parametrization of Van Genuchten IF ( soil_type /= 7 ) THEN ! !-- Calculate the hydraulic conductivity after Van Genuchten !-- (1980) h_vg = ( ( (m_res(j,i) - m_sat(j,i)) / ( m_res(j,i) - & MAX(m_soil(k,j,i),m_wilt(j,i)) ) )**(n_vg(j,i) & / (n_vg(j,i)-1.0_wp)) - 1.0_wp & )**(1.0_wp/n_vg(j,i)) / alpha_vg(j,i) gamma_temp(k) = gamma_w_sat(j,i) * ( ( (1.0_wp + & (alpha_vg(j,i)*h_vg)**n_vg(j,i))**(1.0_wp & -1.0_wp/n_vg(j,i)) - (alpha_vg(j,i)*h_vg & )**(n_vg(j,i)-1.0_wp))**2 ) & / ( (1.0_wp + (alpha_vg(j,i)*h_vg & )**n_vg(j,i))**((1.0_wp - 1.0_wp/n_vg(j,i)) & *(l_vg(j,i) + 2.0_wp)) ) ! !-- Parametrization of Clapp & Hornberger ELSE gamma_temp(k) = gamma_w_sat(j,i) * (m_soil(k,j,i) & / m_sat(j,i) )**(2.0_wp * b_ch + 3.0_wp) ENDIF ENDDO IF ( humidity ) THEN ! !-- Calculate soil diffusivity (lambda_w) at the _stag level !-- using linear interpolation. To do: replace this with !-- ECMWF-IFS Eq. 8.81 DO k = nzb_soil, nzt_soil-1 lambda_w(k,j,i) = lambda_temp(k) + & ( lambda_temp(k+1) - lambda_temp(k) ) & * 0.5_wp * dz_soil_stag(k) * ddz_soil(k+1) gamma_w(k,j,i) = gamma_temp(k) + & ( gamma_temp(k+1) - gamma_temp(k) ) & * 0.5_wp * dz_soil_stag(k) * ddz_soil(k+1) ENDDO ! ! !-- In case of a closed bottom (= water content is conserved), set !-- hydraulic conductivity to zero to that no water will be lost !-- in the bottom layer. IF ( conserve_water_content ) THEN gamma_w(nzt_soil,j,i) = 0.0_wp ELSE gamma_w(nzt_soil,j,i) = lambda_temp(nzt_soil) ENDIF !-- The root extraction (= root_extr * qsws_veg_eb / (rho_l * l_v)) !-- ensures the mass conservation for water. The transpiration of !-- plants equals the cumulative withdrawals by the roots in the !-- soil. The scheme takes into account the availability of water !-- in the soil layers as well as the root fraction in the !-- respective layer. Layer with moisture below wilting point will !-- not contribute, which reflects the preference of plants to !-- take water from moister layers. ! !-- Calculate the root extraction (ECMWF 7.69, modified so that the !-- sum of root_extr = 1). The energy balance solver guarantees a !-- positive transpiration, so that there is no need for an !-- additional check. m_total = 0.0_wp DO k = nzb_soil, nzt_soil IF ( m_soil(k,j,i) .GT. m_wilt(j,i) ) THEN m_total = m_total + root_fr(k,j,i) * m_soil(k,j,i) ENDIF ENDDO DO k = nzb_soil, nzt_soil IF ( m_soil(k,j,i) .GT. m_wilt(j,i) ) THEN root_extr(k) = root_fr(k,j,i) * m_soil(k,j,i) / m_total ELSE root_extr(k) = 0.0_wp ENDIF ENDDO ! !-- Prognostic equation for soil water content m_soil tend(:) = 0.0_wp tend(nzb_soil) = ( lambda_w(nzb_soil,j,i) * ( & m_soil(nzb_soil+1,j,i) - m_soil(nzb_soil,j,i) ) & * ddz_soil(nzb_soil) - gamma_w(nzb_soil,j,i) - ( & root_extr(nzb_soil) * qsws_veg_eb(j,i) & + qsws_soil_eb(j,i) ) * drho_l_lv ) & * ddz_soil_stag(nzb_soil) DO k = nzb_soil+1, nzt_soil-1 tend(k) = ( lambda_w(k,j,i) * ( m_soil(k+1,j,i) & - m_soil(k,j,i) ) * ddz_soil(k) - gamma_w(k,j,i)& - lambda_w(k-1,j,i) * (m_soil(k,j,i) - & m_soil(k-1,j,i)) * ddz_soil(k-1) & + gamma_w(k-1,j,i) - (root_extr(k) & * qsws_veg_eb(j,i) * drho_l_lv) & ) * ddz_soil_stag(k) ENDDO tend(nzt_soil) = ( - gamma_w(nzt_soil,j,i) & - lambda_w(nzt_soil-1,j,i) & * (m_soil(nzt_soil,j,i) & - m_soil(nzt_soil-1,j,i)) & * ddz_soil(nzt_soil-1) & + gamma_w(nzt_soil-1,j,i) - ( & root_extr(nzt_soil) & * qsws_veg_eb(j,i) * drho_l_lv ) & ) * ddz_soil_stag(nzt_soil) m_soil_p(nzb_soil:nzt_soil,j,i) = m_soil(nzb_soil:nzt_soil,j,i)& + dt_3d * ( tsc(2) * tend(:) & + tsc(3) * tm_soil_m(:,j,i) ) ! !-- Account for dry soils (find a better solution here!) m_soil_p(:,j,i) = MAX(m_soil_p(:,j,i),0.0_wp) ! !-- Calculate m_soil tendencies for the next Runge-Kutta step IF ( timestep_scheme(1:5) == 'runge' ) THEN IF ( intermediate_timestep_count == 1 ) THEN DO k = nzb_soil, nzt_soil tm_soil_m(k,j,i) = tend(k) ENDDO ELSEIF ( intermediate_timestep_count < & intermediate_timestep_count_max ) THEN DO k = nzb_soil, nzt_soil tm_soil_m(k,j,i) = -9.5625_wp * tend(k) + 5.3125_wp & * tm_soil_m(k,j,i) ENDDO ENDIF ENDIF ENDIF ENDDO ENDDO ! !-- Calculate surface specific humidity IF ( humidity ) THEN CALL calc_q_surface ENDIF END SUBROUTINE lsm_soil_model !------------------------------------------------------------------------------! ! Description: ! ------------ ! Calculation of specific humidity of the surface layer (surface) !------------------------------------------------------------------------------! SUBROUTINE calc_q_surface IMPLICIT NONE INTEGER :: i !: running index INTEGER :: j !: running index INTEGER :: k !: running index REAL(wp) :: resistance !: aerodynamic and soil resistance term DO i = nxlg, nxrg DO j = nysg, nyng k = nzb_s_inner(j,i) ! !-- Calculate water vapour pressure at saturation e_s = 0.01_wp * 610.78_wp * EXP( 17.269_wp * ( t_surface(j,i) & - 273.16_wp ) / ( t_surface(j,i) & - 35.86_wp ) ) ! !-- Calculate specific humidity at saturation q_s = 0.622_wp * e_s / surface_pressure resistance = r_a(j,i) / (r_a(j,i) + r_s(j,i)) ! !-- Calculate specific humidity at surface q_p(k,j,i) = resistance * q_s + (1.0_wp - resistance) & * q_p(k+1,j,i) ENDDO ENDDO END SUBROUTINE calc_q_surface !------------------------------------------------------------------------------! ! Description: ! ------------ ! Swapping of timelevels !------------------------------------------------------------------------------! SUBROUTINE lsm_swap_timelevel ( mod_count ) IMPLICIT NONE INTEGER, INTENT(IN) :: mod_count #if defined( __nopointer ) t_surface = t_surface_p t_soil = t_soil_p IF ( humidity ) THEN m_soil = m_soil_p m_liq_eb = m_liq_eb_p ENDIF #else SELECT CASE ( mod_count ) CASE ( 0 ) t_surface => t_surface_1; t_surface_p => t_surface_2 t_soil => t_soil_1; t_soil_p => t_soil_2 IF ( humidity ) THEN m_soil => m_soil_1; m_soil_p => m_soil_2 m_liq_eb => m_liq_eb_1; m_liq_eb_p => m_liq_eb_2 ENDIF CASE ( 1 ) t_surface => t_surface_2; t_surface_p => t_surface_1 t_soil => t_soil_2; t_soil_p => t_soil_1 IF ( humidity ) THEN m_soil => m_soil_2; m_soil_p => m_soil_1 m_liq_eb => m_liq_eb_2; m_liq_eb_p => m_liq_eb_1 ENDIF END SELECT #endif END SUBROUTINE lsm_swap_timelevel END MODULE land_surface_model_mod