== Land Surface Parameters ==
[[TracNav(doc/app/partoc|nocollapse)]]

Since r1551 a full land surface model (LSM) is available in PALM. It consists of a four 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. More more details, see [wiki:doc/tec/lsm land surface model documentation].

All parts of the LSM code are modularized in module [/browser/palm/trunk/SOURCE/land_surface_model.f90 land_surface_model_mod]. In this context, a new Fortran NAMELIST {{{lsm_par}}} was added, containing all LSM-related steering parameters. The LSM is automatically activated when a {{{lsm_par}}} 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_type vegetation types], 7 pre-defined [#pavement_type pavement types], 4 pre-defined [#water_type water types], and 6 different [#soil_type 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 soil_type], and [#vegetation_type vegetation_type]. Setting of initial vertical profiles of [#soil_temperature soil_temperature] and [#soil_moisture soil_moisture] is recommended. 

Note that the use of the LSM requires using a [wiki:doc/tec/radiation radiation model].


\\\\\\\\\\\\
'''NAMELIST group name: lsm_par''' \\\\

||='''Parameter Name'''  =||='''[../fortrantypes FORTRAN Type]'''  =||='''Default Value'''  =||='''Explanation'''  =||
|----------------
{{{#!td style="vertical-align:top"
[=#alpha_vangenuchten '''alpha_vangenuchten''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Value of the coefficient alpha for the calculation of the hydraulic conductivity of soil in the parametrization after Van Genuchten (1980).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#c_surface '''c_surface''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
20000.0
}}}
{{{#!td
Heat capacity of the surface (skin layer) per unit of area (in J/m²/K).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#canopy_resistance_coefficient '''canopy_resistance_coefficient''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
A coefficient (in 1/hPa) for the dependence of the canopy resistance on water vapor pressure deficit. Only relevant for high vegetation.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#conserve_water_content '''conserve_water_content''']
}}}
{{{#!td style="vertical-align:top"
L
}}}
{{{#!td style="vertical-align:top"
.T.
}}}
{{{#!td
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.

}}}
|----------------
{{{#!td style="vertical-align:top"
[=#field_capacity '''field_capacity''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Soil moisture at field capacity (in m³/m³).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#f_shortwave_incoming '''f_shortwave_incoming''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Fraction of the net shortwave radiation that is transmitted directly to the top soil layer. 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.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#hydraulic_conductivity '''hydraulic_conductivity''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Hydraulic conductivity of the soil at saturation (in m/s).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#lambda_surface_stable '''lambda_surface_stable''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Heat conductivity (between atmosphere and soil) (in W/m²/K) in case of stable stratification.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#lambda_surface_unstable '''lambda_surface_unstable''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Heat conductivity (between atmosphere and soil) (in W/m²/K) in case of unstable stratification.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#leaf_area_index '''leaf_area_index''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Leaf area index of the canopy (in m²/m²).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#l_vangenuchten '''l_vangenuchten''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Value of the coefficient {{{l}}} for the calculation of the hydraulic conductivity of soil in the parametrization after Van Genuchten (1980).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#min_canopy_resistance '''min_canopy_resistance''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Minimum canopy (i.e., stomatal) resistance (in s/m).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#min_soil_resistance '''min_soil_resistance''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
50.0
}}}
{{{#!td
Minimum soil resistance (in s/m).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#pavement_depth '''pavement_depth''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [=#pavement_type pavement_type]
}}}
{{{#!td
Depth of the paved surface (m).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#pavement_heat_capacity '''pavement_heat_capacity''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [=#pavement_type pavement_type]
}}}
{{{#!td
Heat capacity of the pavement.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#pavement_heat_conduct '''pavement_heat_conduct''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [=#pavement_type pavement_type]
}}}
{{{#!td
Heat capacity of the pavement.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#pavement_type '''pavement_type''']
}}}
{{{#!td style="vertical-align:top"
I
}}}
{{{#!td style="vertical-align:top"
1
}}}
{{{#!td
Pavement type classification according to the following list.

|| 0||user defined ||All pavement parameters must be explicitly set by the user. ||
|| 1||asphalt ||||
|| 2||concrete ||||
|| 3||asphalt/concrete mix ||||
|| 4||brick pavers ||||
|| 5||cobblestone pavers ||||
|| 6||sett pavers ||||
|| 7||gravel pavers ||||

||= '''pavement_type'''=||='''z0_pavement''' =||='''z0h_pavement''' =||='''pavement_heat_conduct''' =||='''pavement_heat_capacity''' =||
||  1|| 0.05|| 1.0E-4|| 1.0E-5|| 1.00|| 1.94E6||
||  2|| 0.05|| 1.0E-4|| 1.0E-5|| 1.00|| 1.94E6||
||  3|| 0.05|| 1.0E-4|| 1.0E-5|| 1.00|| 1.94E6||
||  4|| 0.05|| 1.0E-4|| 1.0E-5|| 1.00|| 1.94E6||
||  5|| 0.05|| 1.0E-4|| 1.0E-5|| 1.00|| 1.94E6||
||  6|| 0.05|| 1.0E-4|| 1.0E-5|| 1.00|| 1.94E6||
||  7|| 0.05|| 1.0E-4|| 1.0E-5|| 1.00|| 1.94E6||
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#residual_moisture '''residual_moisture''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Residual soil moisture content (in m³/m³).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#saturation_moisture '''saturation_moisture''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Soil moisture at saturation (in m³/m³).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#wilting_point '''wilting_point''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Soil moisture at permanent wilting point (in m³/m³).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#n_vangenuchten '''n_vangenuchten''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#soil_type soil_type]
}}}
{{{#!td
Value of the coefficient {{{n}}} for the calculation of the hydraulic conductivity of soil in the parametrization after Van Genuchten (1980).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#root_fraction '''root_fraction''']
}}}
{{{#!td style="vertical-align:top"
R(4)
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Root distribution 
{{{
#!Latex
\[ R_k \]
}}}
over the four soil layers (with index {{{k}}}).

It must hold that
{{{
#!Latex
$ \sum_{k=1}^4 R_k = 1. $
}}}

}}}
|----------------
{{{#!td style="vertical-align:top"
[=#skip_time_do_lsm '''skip_time_do_lsm''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
0.0
}}}
{{{#!td
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.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#soil_moisture '''soil_moisture''']
}}}
{{{#!td style="vertical-align:top"
R(4)
}}}
{{{#!td style="vertical-align:top"
4*0.0
}}}
{{{#!td
Soil moisture distribution over the four soil layers (given by [#zs zs]). Soil moisture is defined at the center of the soil volumes (see [#zs LSM grid]) and is only predicted when [wiki:doc/app/inipar#humidity humidity]{{{ = .T.}}}.

'''Default (dry):'''
{{{
soil_moisture = 0.0, 0.0, 0.0, 0.0
}}}
Note that the soil moisture is internally set to a minimum value according to [#wilting_point wilting_point] at model start.

}}}
|----------------
{{{#!td style="vertical-align:top"
[=#soil_temperature '''soil_temperature''']
}}}
{{{#!td style="vertical-align:top"
R(5)
}}}
{{{#!td style="vertical-align:top"
see Description
}}}
{{{#!td
Soil temperature distribution over the four soil layers in K.

'''Default:'''
{{{
soil_temperature = 290.0, 287.0, 285.0, 283.0, 283.0
}}}
The first four values represent the temperature of the soil layers (defined at the center of the layers of depth [#zs zs], see [#zs LSM grid]. The last (fifth) value represents the deep soil temperature, which is fixed (boundary condition).

}}}
|----------------
{{{#!td style="vertical-align:top"
[=#soil_type '''soil_type''']
}}}
{{{#!td style="vertical-align:top"
I
}}}
{{{#!td style="vertical-align:top"
3
}}}
{{{#!td
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_vangenuchten] (alpha_vg), [#l_vangenuchten l_vangenuchten] (l_vg), [#n_vangenuchten n_vangenuchten] (n_vg), [#hydraulic_conductivity hydraulic_conductivity] (gamma_w_sat), [#saturation_moisture saturation_moisture] (m_sat), [#field_capacity field_capacity] (m_fc), [#wilting_point wilting_point] (m_wilt), [#residual_moisture 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||
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#surface_type '''surface_type''']
}}}
{{{#!td style="vertical-align:top"
C
}}}
{{{#!td style="vertical-align:top"
'netcdf'
}}}
{{{#!td
Surface type classification. Allowed are 'vegetation', 'pavement', 'water', and 'netcdf'. Depdening on {{{surface_type}}}, the required parameters are set via setting of [#vegetation_type vegetation_type], [#pavement_type pavement_type], or [#water_type water_type]. When {{{surface_type = 'netcdf'}}}, all input data required by the LSM is expected to be provided from an NetCDF input file (NetCDF support for input files is currently under way).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#vegetation_coverage '''vegetation_coverage''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Vegetation coverage of the surface (values of 0-1). The residual fraction is considered to be bare soil.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#vegetation_type '''vegetation_type''']
}}}
{{{#!td style="vertical-align:top"
I
}}}
{{{#!td style="vertical-align:top"
2
}}}
{{{#!td
Vegetation type to be used in the land surface model.

The user can choose from 19 different pre-defined vegetation classes according to 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 ||
|| 5||evergreen broadleaf trees ||
|| 6||deciduous broadleaf trees ||
|| 7||tall grass ||
|| 8||desert ||
|| 9||tundra ||
|| 10||irrigated crops ||
|| 11||semidesert ||
|| 12*||ice caps and glaciers ||
|| 13||bogs and marshes ||
|| 14||evergreen shrubs ||
|| 15||deciduous shrubs ||
|| 16||mixed forest/woodland ||
|| 17||interrupted forest ||
|| 18||pavement/roads ||
(* not yet implemented)

The following parameters will then be automatically set: [#min_canopy_resistance min_canopy_resistance] (r_c_min), [#leaf_area_index leaf_area_index] (LAI), [#vegetation_coverage vegetation_coverage] (c_veg), [#canopy_resistance_coefficient canopy_resistance_coefficient] (gD), [#z0_vegetation z0_vegetation], [#z0h_vegetation z0h_vegetation], [#lambda_surface_stable lambda_surface_stable] (lambda_s), [#lambda_surface_unstable lambda_surface_unstable] (lambda_u), [#f_shortwave_incoming f_shortwave_incoming] (f_sw_in), [#root_fraction 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_vegetation (m)''' =||='''z0h_vegetation''' =||='''lambda_s (W/m²/K)''' =||='''lambda_u (W/m²/K)''' =||='''f_sw_in''' =||
||  1|| 180.0|| 3.00|| 0.90|| 0.00||   0.25||  0.25E-2||   10.0||   10.0|| 0.05||
||  2|| 180.0|| 3.00|| 0.90|| 0.00||   0.25||  0.25E-2||   10.0||   10.0|| 0.05||
||  3|| 110.0|| 2.00|| 0.85|| 0.00||   0.20||  0.20E-2||   10.0||   10.0|| 0.05||
||  4|| 500.0|| 5.00|| 0.90|| 0.03||   2.00||     2.00||   20.0||   15.0|| 0.03||
||  5|| 500.0|| 5.00|| 0.90|| 0.03||   2.00||     2.00||   20.0||   15.0|| 0.03||
||  6|| 175.0|| 5.00|| 0.90|| 0.03||   2.00||     2.00||   20.0||   15.0|| 0.03||
||  7|| 240.0|| 6.00|| 0.99|| 0.13||   2.00||     2.00||   20.0||   15.0|| 0.03||
||  8|| 100.0|| 2.00|| 0.70|| 0.00||   0.47||  0.47E-2||   10.0||   10.0|| 0.05||
||  9|| 250.0|| 0.05|| 0.00|| 0.00||  0.013|| 0.013E-2||   15.0||   15.0|| 0.00||
|| 10||  80.0|| 1.00|| 0.50|| 0.00||  0.034|| 0.034E-2||   10.0||   10.0|| 0.05||
|| 11|| 180.0|| 3.00|| 0.90|| 0.00||    0.5||  0.50E-2||   10.0||   10.0|| 0.05||
|| 12|| 150.0|| 0.50|| 0.10|| 0.00||   0.17||  0.17E-2||   10.0||   10.0|| 0.05||
|| 13*||   0.0|| 0.00|| 0.00|| 0.00|| 1.3E-3||   1.3E-4||   58.0||   58.0|| 0.00||
|| 14|| 240.0|| 4.00|| 0.60|| 0.00||   0.83||  0.83E-2||   10.0||   10.0|| 0.05||
|| 15|| 225.0|| 3.00|| 0.50|| 0.00||   0.10||  0.10E-2||   10.0||   10.0|| 0.05||
|| 16|| 225.0|| 1.50|| 0.50|| 0.00||   0.25||  0.25E-2||   10.0||   10.0|| 0.05||
|| 17|| 250.0|| 5.00|| 0.90|| 0.03||   2.00||  2.00E-2||   20.0||   15.0|| 0.03||
|| 18|| 175.0|| 2.50|| 0.90|| 0.03||   1.10||  1.10E-2||   20.0||   15.0|| 0.03||
(* not yet implemented)\\
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#zs '''zs''']
}}}
{{{#!td style="vertical-align:top"
R(4)
}}}
{{{#!td style="vertical-align:top"
see description
}}}
{{{#!td
Depths of the four soil layers (in m). Note that the model operates with negative values below the surface, data output will thus be at located at {{{-zs}}}.

'''Default:'''
{{{
zs = 0.005, 0.02, 0.04, 0.07, 0.15, 0.28, 1.00, 2.89,
}}}
'''Schematic overview of the soil model grid:'''
[[Image(wall_concept_type1.png,300px)]]

}}}
|----------------
{{{#!td style="vertical-align:top"
[=#z0_vegetation '''z0_vegetation''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Roughness length for momentum (in m) for vegetation surface types. The setting of {{{z0_vegetation}}} overwrites [wiki:doc/app/inipar#roughness_length roughness_length], unless {{{z0_vegetion}}} is not set.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#z0h_vegetation '''z0h_vegetation''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Roughness length for heat (in m). The setting of {{{z0h_vegetation}}} overwrites [wiki:doc/app/inipar#z0h_factor z0h_factor]. In this case, the roughness length for heat is calculated from [wiki:doc/app/inipar#z0h_factor z0h_factor] and {{{z0h_vegetation}}} (or [wiki:doc/app/inipar#roughness_length #roughness_length]).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#z0q_vegetation '''z0q_vegetation''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
depending on [#vegetation_type vegetation_type]
}}}
{{{#!td
Roughness length for moisture (in m). When {{{z0q_vegetation}}} is not explicitly set, it is set to the value of {{{z0h}}}.
}}}