Land Surface Parameters

This page is part of the Land Surface Model (LSM) documentation.
It contains a listing of all PALM input parameters used to steer the LSM.
Please also see the technical documentation.

Since r1551 a full land surface model (LSM) is available in PALM. It consists of a multi layer soil model, predicting soil temperature and moisture content, and a solver for the energy balance at the surface. Moreover, a liquid water reservoir accounts for the presence of liquid water on plants due to dew/fog. The implementation is based on the ECMWF-IFS land surface parametrization (TESSEL) and its adaption in the DALES model. For more details see land surface model documentation.

All parts of the LSM code are modularized in module land_surface_model_mod. In this context, a new Fortran namelist land_surface_parameters was added, containing all LSM-related steering parameters. The LSM is automatically activated when a land_surface_parameters is set in the parameter file (_p3d). The user can easily set all relevant LSM parameters by choosing between 3 different surface types (vegetation, pavement, water) and various pre-defined surface classes 17 pre-defined vegetation types, 7 pre-defined pavement types, 4 pre-defined water types, and 6 different soil types. The default setting of the LSM is a soil of medium porosity covered to 85% with short grass. It is also possible to modify the pre-defined vegetation/soil types by overwriting some of the parameters. Moreover it is possible to create user-defined vegetation and soil types from scratch.

A minimum configuration of the LSM requires setting of the parameters soil_type, vegetation_type, soil_temperature, deep_soil_temperature, and soil_moisture.

Note that the use of the LSM requires using a radiation model.

Namelist group name: land_surface_parameters

Parameter Name	Fortran Type	Default Value	Explanation
aero_resist_kray	L	.T.	If set to .TRUE., the parameterization of the aerodynamic resistance for vertical land surface elements follows Krayenhoff & Voogt (2007).
alpha_vangenuchten	R	depending on soil_type	Value of the coefficient alpha for the calculation of the hydraulic conductivity of soil in the parametrization after Van Genuchten (1980).
c_surface	R	depending on vegetation_type	Heat capacity of the surface (skin layer) per unit of area (in J/m²/K) in case of vegetated surfaces. Note that this parameter does not apply in case of water_type and pavement_type surfaces.
canopy_resistance _coefficient	R	depending on vegetation_type	A coefficient (in 1/hPa) for the dependence of the canopy resistance on water vapor pressure deficit. Only relevant for high vegetation.
conserve_water_content	L	.T.	Flag parameter for the bottom boundary condition of the soil model. The user can choose between the following two options: '.T.' Closed bottom (bedrock, no drainage). Conservation of water in the soil and atmosphere is guaranteed. '.F.' Open bottom (free drainage). Water can leave the soil model and conservation of water is not guaranteed.
constant_roughness	L	.F.	Keep prescribed roughness length constant in time. This parameter only applied to water_surfaces, where the roughness lengths may depend on wind speed and usually follows parameterizations after Charnock (1955) and Beljaars (1994).
deep_soil_temperature	R	9999999.9	Deep soil temperature (K) used as bottom boundary condition for the heat diffusion in the soil model. Note, in case soil temperature is given in dynamic input file, the deep soil temperature will be taken from the deepest level.
dz_soil	R(20)	see description	Thickness of the individual soil layers (in m). Note that the model operates with negative values below the surface which will appear in the output files. Up to 20 individual soil layers can be chosen. Default (eight layer configuration): dz_soil = 0.01, 0.02, 0.04, 0.06, 0.14, 0.26, 0.54, 1.86 Schematic overview of the soil model grid: (example for natural land surfaces with vegetation)
field_capacity	R	depending on soil_type	Soil moisture at field capacity (in m³/m³).
f_shortwave_incoming	R	depending on vegetation_type	Fraction of the net shortwave radiation that is transmitted directly to the top soil layer (0-1). The remaining fraction of the shortwave radiation is absorbed by the surface (skin layer). This parameter has not been fully implemented yet and is fixed to 0.
hydraulic_conductivity	R	depending on soil_type	Hydraulic conductivity of the soil at saturation (in m/s).
lambda_surface_stable	R	depending on vegetation_type	Heat conductivity (between atmosphere and soil) (in W/m²/K) in case of stable stratification.
lambda_surface_unstable	R	depending on vegetation_type	Heat conductivity (between atmosphere and soil) (in W/m²/K) in case of unstable stratification.
leaf_area_index	R	depending on vegetation_type	Leaf area index of the canopy (in m²/m²).
l_vangenuchten	R	depending on soil_type	Value of the coefficient l for the calculation of the hydraulic conductivity of soil in the parametrization after Van Genuchten (1980).
min_canopy_resistance	R	depending on vegetation_type	Minimum canopy (i.e., stomatal) resistance (in s/m).
min_soil_resistance	R	50.0	Minimum soil resistance (in s/m).
n_vangenuchten	R	depending on soil_type	Value of the coefficient n for the calculation of the hydraulic conductivity of soil in the parametrization after Van Genuchten (1980).
pavement_depth_level	I	depending on pavement_type	Extend of the depth of the pavement in grid levels below the surface.
pavement_heat_capacity	R	depending on pavement_type	Heat capacity of the pavement (J/K/m³).
pavement_heat_conduct	R	depending on pavement_type	Thermal conductivity of the pavement (W/m/K).
pavement_type	I	1	Pavement type classification according to the following list and which loosely follows the Open Street Map classification. Note that the default pavement types (i.e. pavement_type /= 0) is only allowed in combination with the default soil layer configuration. 0 user defined All pavement parameters must be explicitly set by the user. 1 asphalt/concrete mix 2 asphalt (asphalt concrete) 3 concrete (Portland concrete) 4 sett 5 paving stones 6 cobblestone 7 metal 8 wood 9 gravel 10 fine gravel 11 pebblestone 12 woodchips 13 tartan (sports) 14 artifical turf (sports) 15 clay (sports) Pavement parameters: pavement type z0_pavement (m) z0h_pavement (m) albedo_type emissivity pavement_depth_level 1 5.0E-2 5.0E-4 18 0.97 6 2 5.0E-2 5.0E-4 19 0.94 6 3 1.0E-2 1.0E-4 20 0.98 6 4 1.0E-2 1.0E-4 21 0.93 6 5 1.0E-2 1.0E-4 22 0.97 6 6 1.0E-2 1.0E-4 23 0.97 6 7 1.0E-2 1.0E-4 24 0.97 6 8 1.0E-2 1.0E-4 25 0.94 6 9 1.0E-2 1.0E-4 26 0.98 6 10 1.0E-2 1.0E-4 27 0.93 6 11 1.0E-2 1.0E-4 28 0.97 6 12 1.0E-2 1.0E-4 29 0.97 6 13 1.0E-2 1.0E-4 30 0.97 6 14 1.0E-2 1.0E-4 31 0.94 6 15 1.0E-2 1.0E-4 32 0.98 6 Pavement thermal conductivity (will be updated in near future): pavement type layer 1 layer 2 layer 3 layer 4 layer 5 layer 6 layer 7 layer 8 Notes 1 0.75 0.75 0.75 0.75 0.75 0.75 - - 2 0.75 0.75 0.75 0.75 0.75 0.75 - - 3 0.89 0.89 0.89 0.89 0.89 0.89 - - 4 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 5 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 6 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 7 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 8 0.70 0.70 0.70 0.70 0.70 0.70 - - 9 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 10 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 11 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 12 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 13 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 14 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 15 1.00 1.00 1.00 1.00 1.00 1.00 - - *1 (*1) preliminary/dummy values. Pavement heat capacity (will be updated in near future): pavement type layer 1 layer 2 layer 3 layer 4 layer 5 layer 6 layer 7 layer 8 1 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 2 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 3 1.76E6 1.76E6 1.76E6 1.76E6 1.76E6 1.76E6 - - 4 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 5 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 7 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 8 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 9 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 10 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 11 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 12 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 13 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 14 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 15 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 1.94E6 - - *1 (*1) preliminary/dummy values.
residual_moisture	R	depending on soil_type	Residual soil moisture content (in m³/m³).
root_fraction	R(20)	depending on vegetation_type	Root distribution. A value must be assigned to each soil layer (1-N) (see dz_soil). over the N soil layers (with index k). It must hold that where N is the number of soil layers used. If root_fraction is not set, a distribution is inferred based on the setting of vegetation_type and the following look-up table for a four-layer soil configuration (using interpolation): vegetation_type layer 1 (0.00 - 0.07 m) layer 2 (0.07 - 0.28 m) layer 3 (0.28 - 1.00 m) layer 4 (1.00 - 2.89 m) 1 0.00 0.00 0.00 0.00 2 0.24 0.41 0.31 0.04 3 0.35 0.38 0.23 0.04 4 0.26 0.39 0.29 0.06 5 0.26 0.38 0.29 0.07 6 0.24 0.38 0.31 0.07 7 0.25 0.34 0.27 0.14 8 0.27 0.27 0.27 0.09 9 1.00 0.00 0.00 0.00 10 0.47 0.45 0.08 0.00 11 0.24 0.41 0.31 0.04 12 0.17 0.31 0.33 0.19 13 0.00 0.00 0.00 0.00 14 0.25 0.34 0.27 0.11 15 0.23 0.36 0.30 0.11 16 0.23 0.36 0.30 0.11 17 0.19 0.35 0.36 0.10 18 0.19 0.35 0.36 0.10
saturation_moisture	R	depending on soil_type	Soil moisture at saturation (in m³/m³).
skip_time_do_lsm	R	0.0	Time after which the land surface model is switched on. This parameter can be used to allow the LES model to develop turbulence before it is affected by the land surface.
soil_moisture	R(20)	20*0.0	Soil moisture distribution over the N soil layers (m³/m³) (given by dz_soil). Soil moisture is defined at the center of the soil layers (see dz_soil) and is only predicted when humidity = .T.. Default (dry, eight layer configuration): soil_moisture = 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, Please note, in case a dynamic input file is available soil moisture will be initialized by dynamic input.
soil_temperature	R(21)	20*9999999.9	Soil temperature distribution over the N soil layers (in K). Example (eight layer configuration): soil_temperature = 300.0, 300.0, 300.0, 300.0, 300.0, 300.0, 300.0, 300.0, The eight values here represent the temperature of the soil layers (defined at the center of the layers of depths dz_soil. Please note, in case a dynamic input file is available soil temperature will be initialized by dynamic input.
soil_type	I	3	Soil type to be used in the soil model. The user can choose from 6 soil types according to the ECMWF-IFS classification (parametrization after Van Genuchten (1980): soil_type Description Notes 0 user defined All soil-related parameters must be explicitly set by the user. 1 coarse 2 medium 3 medium-fine 4 fine 5 very fine 6 organic The following parameters will then be automatically set: alpha_vangenuchten (alpha_vg), l_vangenuchten (l_vg), n_vangenuchten (n_vg), hydraulic_conductivity (gamma_w_sat), saturation_moisture (m_sat), field_capacity (m_fc), wilting_point (m_wilt), residual_moisture (m_res). soil_type alpha_vg l_vg n_vg gamma_w_sat (m/s) m_sat (m³/m³) m_fc (m³/m³) m_wilt (m³/m³) m_res (m³/m³) 1 3.83 1.150 1.38 6.94E-6 0.403 0.244 0.059 0.025 2 3.14 -2.342 1.28 1.16E-6 0.439 0.347 0.151 0.010 3 0.83 -0.588 1.25 0.26E-6 0.430 0.383 0.133 0.010 4 3.67 -1.977 1.10 2.87E-6 0.520 0.448 0.279 0.010 5 2.65 2.500 1.10 1.74E-6 0.614 0.541 0.335 0.010 6 1.30 0.400 1.20 1.20E-6 0.766 0.663 0.267 0.010
surface_type	C	'netcdf'	Surface type classification. Allowed are 'vegetation', 'pavement', 'water', and 'netcdf'. Depdening on surface_type, the required parameters are set via setting of vegetation_type, pavement_type, or water_type. When surface_type = 'netcdf', all input data required by the LSM is expected to be provided from an NetCDF input file.
vegetation_coverage	R	depending on vegetation_type	Vegetation coverage of the surface (values of 0-1, pixel-size). The residual fraction is considered to be bare soil. For small grid spacings, the vegetation coverage can be considered to be one.
vegetation_type	I	2	Vegetation type to be used in the land surface model. The user can choose from 19 different pre-defined vegetation classes in the style of the ECMWF-IFS classification: vegetation_type Description 0 user defined 1 bare soil 2 crops, mixed farming 3 short grass 4 evergreen needleleaf trees 5 deciduous needleleaf trees 6 evergreen broadleaf trees 7 deciduous broadleaf trees 8 tall grass 9 desert 10 tundra 11 irrigated crops 12 semidesert 13* ice caps and glaciers 14 bogs and marshes 15 evergreen shrubs 16 deciduous shrubs 17 mixed forest/woodland 18 interrupted forest (* not yet implemented) The following parameters will then be automatically set: min_canopy_resistance (r_c_min), leaf_area_index (LAI), vegetation_coverage (c_veg), canopy_resistance_coefficient (gD), z0_vegetation, z0h_vegetation, lambda_surface_stable (lambda_s), lambda_surface_unstable (lambda_u), f_shortwave_incoming (f_sw_in), root_fraction. The following tables provide an overview of the parameter values. vegetation _type r_c_min (s/m) LAI (m²/m²) c_veg gD (1/hPa) z0_vegeta tion (m) z0h_vege tation (m) lambda_s (W/m²/K) lambda_u (W/m²/K) f_sw_in c_surface albedo _type emissivity 1 0.0 0.00 0.00 0.00 0.005 0.5E-4 0.0 0.0 0.00 0.0 17.0 0.94 2 180.0 3.00 1.00 0.00 0.10 0.0001 10.0 10.0 0.05 0.0 2 0.95 3 110.0 2.00 1.00 0.00 0.03 0.30E-4 10.0 10.0 0.05 0.0 5 0.95 4 500.0 5.00 1.00 0.03 2.00 2.00 20.0 15.0 0.03 0.0 6 0.97 5 500.0 5.00 1.00 0.03 2.00 2.00 20.0 15.0 0.03 0.0 8 0.97 6 175.0 5.00 1.00 0.03 2.00 2.00 20.0 15.0 0.03 0.0 9 0.97 7 240.0 6.00 0.99 0.13 2.00 2.00 20.0 15.0 0.03 0.0 7 0.97 8 100.0 2.00 0.70 0.00 0.47 0.47E-2 10.0 10.0 0.05 0.0 10 0.97 9 250.0 0.05 0.00 0.00 0.013 0.013E-2 15.0 15.0 0.00 0.0 11 0.94 10 80.0 1.00 0.50 0.00 0.034 0.034E-2 10.0 10.0 0.05 0.0 13 0.97 11 180.0 3.00 1.00 0.00 0.5 0.50E-2 10.0 10.0 0.05 0.0 2 0.97 12 150.0 0.50 0.10 0.00 0.17 0.17E-2 10.0 10.0 0.05 0.0 11 0.97 13* 0.0 0.00 0.00 0.00 1.3E-3 1.3E-4 58.0 58.0 0.00 0.0 14 0.97 14 240.0 4.00 0.60 0.00 0.83 0.83E-2 10.0 10.0 0.05 0.0 3 0.97 15 225.0 3.00 0.50 0.00 0.10 0.10E-2 10.0 10.0 0.05 0.0 4 0.97 16 225.0 1.50 0.50 0.00 0.25 0.25E-2 10.0 10.0 0.05 0.0 5 0.97 17 250.0 5.00 1.00 0.03 2.00 2.00 20.0 15.0 0.03 0.0 10 0.97 18 175.0 2.50 1.00 0.03 1.10 1.10 20.0 15.0 0.03 0.0 7 0.97 (* not yet implemented)
water_temperature	F	9999999.9	Water temperature (K), by default constant during the entire run.
water_type	I	1	Water type classification according to the following list. 0 user defined All pavement parameters must be explicitly set by the user. 1 lake 2 river 3 ocean 4 pond water_type water_temperature z0_water z0h_water albedo_type emissivity 1 283.0 0.01* 0.001* 1 0.99 2 283.0 0.01* 0.001* 1 0.99 3 283.0 0.01* 0.001* 1 0.99 4 283.0 0.01* 0.001* 1 0.99 if constant_roughness = .F., the roughness lengths are calculated after each time step after Charnock (1955) and Beljaars (1994) and the values from the table are not used.
wilting_point	R	depending on soil_type	Soil moisture at permanent wilting point (in m³/m³).
z0_vegetation	R	depending on vegetation_type	Roughness length for momentum (in m) for vegetation surface types. The setting of z0_vegetation overwrites roughness_length, unless z0_vegetion is not set.
z0h_vegetation	R	depending on vegetation_type	Roughness length for heat (in m). The setting of z0h_vegetation overwrites z0h_factor. In this case, the roughness length for heat is calculated from z0h_factor and z0h_vegetation (or #roughness_length).
z0q_vegetation	R	depending on vegetation_type	Roughness length for moisture (in m). When z0q_vegetation is not explicitly set, it is set to the value of z0h.