== Land Surface Parameters ==
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Since r1551 a full land surface model (LMS) is available in PALM. It consists of a four layer soil model for the soil temperature and moisture contents and a solver for the energy balance at the surface. The implementation is based on the ECMWF-IFS land surface parametrization (TESSEL) and its adaption in the DALES model.

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}}}).

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

||='''Parameter Name'''  =||='''[../fortrantypes FORTRAN Type]'''  =||='''Default Value'''  =||='''Explanation'''  =||
|----------------
{{{#!td style="vertical-align:top"
[=#alpha_vengenuchten '''alpha_vangenuchten''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!td
A coefficient (in 1/hPa) for the dependence of the canopy resistance on water vapor pressure deficit.
}}}
|----------------
{{{#!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 usee 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"
[=#dewfall '''dewfall''']
}}}
{{{#!td style="vertical-align:top"
L
}}}
{{{#!td style="vertical-align:top"
.T.
}}}
{{{#!td
In case dewfall = .T., all supersatured water at the lowest grid level is immediately removed and transferred to the liquid water reservoir (or soil, depending on the [#vegetation_coverage vegetation coverage] and the filling level of the liquid water reservoir). Alternatively, dewfall = .F. will switch off this parametrization (yet to be tested).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#f_shortwave_incoming '''f_shortwave_incoming''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!td
Aerodynamic coupling between canopy 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"
9999999.9
}}}
{{{#!td
Aerodynamic coupling between canopy 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"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!td
Minimum canopy resistance (in s/m).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#field_capacity '''field_capacity''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
9999999.9
}}}
{{{#!td
Soil moisture at field capacity (in m³/m³).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#residual_moisture '''residual_moisture''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!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"
9999999.9
}}}
{{{#!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"
4*9999999.9
}}}
{{{#!td
Root distribution 
{{{
#!Latex
\[ R_k \]
}}}
over the four soil layers (with index {{{k}}}).

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

}}}
|----------------
{{{#!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 (in m³/m³).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#soil_temperature '''soil_temperature''']
}}}
{{{#!td style="vertical-align:top"
R(4)
}}}
{{{#!td style="vertical-align:top"
4*9999999.9
}}}
{{{#!td
Soil temperature distribution over the four soil layers (in K).
}}}
|----------------
{{{#!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 the following table:
||='''veg_class''' =||='''Vegetation type''' =|
||0  ||user defined ||
||1  ||crops, mixed farming ||
||2  ||short grass ||
||3  ||evergreen needleleaf trees ||
||4  ||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 ||inland water ||
||15 ||ocean ||
||16 ||evergreen shrubs ||
||17 ||deciduous shrubs ||
||18 ||mixed forest/woodland ||
||19 ||interrupted forest ||
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#vegetation_coverage '''vegetation_coverage''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
9999999.9
}}}
{{{#!td
Vegetation coverage of the surface (values of 0-1). The residual fraction is considered to be bare soil.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#veg_type '''veg_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 the following table:
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#zs '''zs''']
}}}
{{{#!td style="vertical-align:top"
R(4)
}}}
{{{#!td style="vertical-align:top"
0.07, 0.28, 1.0, 2.89
}}}
{{{#!td
Depths of the four soil layers (in m).
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#z0_eb '''z0_eb''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
9999999.9
}}}
{{{#!td
Roughness length for momentum (in m). The setting of {{{z0_eb}}} overwrites [wiki:doc/app/inipar#roughness_length roughness_length], unless {{{z0_eb}}} is not set.
}}}
|----------------
{{{#!td style="vertical-align:top"
[=#z0h_eb '''z0h_eb''']
}}}
{{{#!td style="vertical-align:top"
R
}}}
{{{#!td style="vertical-align:top"
9999999.9
}}}
{{{#!td
Roughness length for heat and moisture (in m). The setting of {{{z0h_eb}}} overwrites [wiki:doc/app/inipar#z0h_factor z0h_factor], unless {{{z0h_eb}}} is not set. In this case, the roughness length for heat is calculated from [wiki:doc/app/inipar#z0h_factor z0h_factor] and {{{z0h_eb}}} (or [wiki:doc/app/inipar#roughness_length #roughness_length]).
}}}