Changes between Initial Version and Version 1 of doc/app/plant_canopy_parameters

Timestamp:

Mar 19, 2014 11:51:18 AM (11 years ago)

Author:

kanani

Comment:

--

doc/app/plant_canopy_parameters

@@ +1 @@
+== Canopy Parameters ==
+[[TracNav(doc/app/partoc|nocollapse)]] ----noch ändern?
+\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
+'''NAMELIST group name: canopy_par''' \\
+
+||='''Parameter Name'''  =||='''[../fortrantypes FORTRAN Type]'''  =||='''Default Value'''  =||='''Explanation'''  =||
+|----------------
+{{{#!td style="vertical-align:top;width: 150px"
+[=#canopy_mode '''canopy_mode''']
+}}}
+{{{#!td style="vertical-align:top;width: 50px"
+C*20
+}}}
+{{{#!td style="vertical-align:top;width: 75px"
+'block'
+}}}
+{{{#!td
+Canopy mode.\\\\
+Besides using the default value, that will create a horizontally homogeneous plant canopy that extends over the total horizontal extension of the model domain, the user may add code to the user interface (see [#3.5.1 3.5.1]) subroutine {{{user_init_plant_canopy}}} to allow further canopy modes.\\\\
+The setting of '''canopy_mode''' becomes only active, if [#plant_canopy plant_canopy] has been set ''.T.'' and a non-zero [#drag_coefficient drag_coefficient] has been defined.
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#cthf '''cthf''']
+}}}
+{{{#!td style="vertical-align:top"
+R
+}}}
+{{{#!td style="vertical-align:top"
+0.0
+}}}
+{{{#!td
+Average heat flux that is prescribed at the top of the plant canopy.\\\\
+If [#plant_canopy plant_canopy] is set ''.T.'', the user can prescribe a heat flux at the top of the plant canopy.
+It is assumed that solar radiation penetrates the canopy and warms the foliage which, in turn, warms the air in contact with it.\\\\
+'''Note:'''\\
+Instead of using the value prescribed by [#surface_heatflux surface_heatflux], the near surface heat flux is determined from an exponential function that is dependent on the cumulative leaf_area_index (Shaw and Schumann (1992, Boundary Layer Meteorol., 61, 47-64)).
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#drag_coefficient '''drag_coefficient''']
+}}}
+{{{#!td style="vertical-align:top"
+R
+}}}
+{{{#!td style="vertical-align:top"
+0.0
+}}}
+{{{#!td
+Drag coefficient used in the {{{plant_canopy_model}}}.\\\\
+This parameter has to be non-zero, if the parameter [#plant_canopy plant_canopy] is set ''.T.''.
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#lad_surface '''lad_surface''']
+}}}
+{{{#!td style="vertical-align:top"
+R
+}}}
+{{{#!td style="vertical-align:top"
+0.0
+}}}
+{{{#!td
+Surface value of the leaf area density (in m^2^/m^3^).\\\\
+This parameter assigns the value of the leaf area density '''lad''' at the surface (k=0). Starting from this value, the leaf area density profile is constructed with [#lad_vertical_gradient lad_vertical_gradient] and [#lad_vertical_gradient_level lad_vertical_gradient_level].
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#lad_vertical_gradient '''lad_vertical_gradient''']
+}}}
+{{{#!td style="vertical-align:top"
+R(10)
+}}}
+{{{#!td style="vertical-align:top"
+10 * 0.0
+}}}
+{{{#!td
+Gradient(s) of the leaf area density (in m^2^/m^4^).\\\\
+This leaf area density gradient holds starting from the height level defined by [#lad_vertical_gradient_level lad_vertical_gradient_level] (precisely: for all uv levels k where zu(k) > lad_vertical_gradient_level, lad(k) is set: lad(k) = lad(k-1) + dzu(k) * '''lad_vertical_gradient''') up to the level defined by [#pch_index pch_index]. Above that level lad(k) will automatically be set to 0.0. A total of 10 different gradients for 11 height intervals (10 intervals if lad_vertical_gradient_level(1) = 0.0) can be assigned. The leaf area density at the surface is assigned via [#lad_surface lad_surface].  
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#lad_vertical_gradient_level '''lad_vertical_gradient_level''']
+}}}
+{{{#!td style="vertical-align:top"
+R(10)
+}}}
+{{{#!td style="vertical-align:top"
+10 * 0.0
+}}}
+{{{#!td
+Height level from which on the gradient of the leaf area density defined by [#lad_vertical_gradient lad_vertical_gradient] is effective (in m).\\\\
+The height levels have to be assigned in ascending order. The default values result in a leaf area density that is constant with height up to the top of the plant canopy layer defined by [#pch_index pch_index]. For the piecewise construction of temperature profiles see [#lad_vertical_gradient lad_vertical_gradient].
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#leaf_surface_concentration '''leaf_surface_concentration''']
+}}}
+{{{#!td style="vertical-align:top"
+R
+}}}
+{{{#!td style="vertical-align:top"
+0.0
+}}}
+{{{#!td
+Concentration of a passive scalar at the surface of a leaf (in K m/s).\\\\
+This parameter is only of importance in cases in that both, [#plant_canopy plant_canopy] and [#passive_scalar passive_scalar], are set ''.T..'' The value of the concentration of a passive scalar at the surface of a leaf is required for the parametrisation of the sources and sinks of scalar concentration due to the canopy.
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#pch_index '''pch_index''']
+}}}
+{{{#!td style="vertical-align:top"
+I
+}}}
+{{{#!td style="vertical-align:top"
+0
+}}}
+{{{#!td
+Grid point index (scalar) of the upper boundary of the plant canopy layer.\\\\
+Above '''pch_index''' the arrays of leaf area density and [#drag_coeffient drag_coeffient] are automatically set to zero in case of [#plant_canopy plant_canopy] = ''.T.''. Up to '''pch_index''' a leaf area density profile can be prescribed by using the parameters [#lad_surface lad_surface], [#lad_vertical_gradient lad_vertical_gradient] and [#lad_vertical_gradient_level lad_vertical_gradient_level].
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#plant_canopy '''plant_canopy''']
+}}}
+{{{#!td style="vertical-align:top"
+L
+}}}
+{{{#!td style="vertical-align:top"
+.F.
+}}}
+{{{#!td
+Switch for the plant canopy model.\\\\
+If '''plant_canopy''' is set ''.T.'', the plant canopy model of Watanabe (2004, BLM 112, 307-341) is used.\\
+The impact of a plant canopy on a turbulent flow is considered by an additional drag term in the momentum equations and an additional sink term in the prognostic equation for the subgrid-scale TKE. These additional terms depend on the leaf drag coefficient (see [#drag_coefficient drag_coefficient]), and the leaf area density (see [#lad_surface lad_surface], [#lad_vertical_gradient lad_vertical_gradient], [#lad_vertical_gradient_level lad_vertical_gradient_level]). The top boundary of the plant canopy is determined by the parameter [#pch_index pch_index]. For all heights equal or larger than zw(k=pch_index), the leaf area density is 0 (i.e. there is no canopy at these heights!).\\
+By default, a horizontally homogeneous plant canopy is prescribed, if  '''plant_canopy''' is set ''.T.''. However, the user can define other types of plant canopies (see [#canopy_mode canopy_mode]).\\\\
+If '''plant_canopy''' and  [#passive_scalar passive_scalar] are set ''.T.'', the canopy acts as an additional scalar source or sink, respectively. The source/sink strength depends on the scalar concentration at the leaf surface, which generally does not vary with time in PALM, and which can be specified with parameter [#leaf_surface_concentration leaf_surface_concentration].\\\\
+Additional heating by the plant canopy is taken into account, if the default value of parameter [#cthf cthf] is altered in the parameter file. In that case, the value of [#surface_heatflux surface_heatflux] specified in the parameter file is not used in the model. Instead, the near-surface heat flux is derived from an exponential function that depends on the cumulative leaf area index.\\\\
+'''plant_canopy''' = ''.T.'' is only allowed with a non-zero [#drag_coefficient drag_coefficient].
+}}}
+|----------------
+{{{#!td style="vertical-align:top"
+[=#scalar_exchange_coefficient '''scalar_exchange_coefficient''']
+}}}
+{{{#!td style="vertical-align:top"
+R
+}}}
+{{{#!td style="vertical-align:top"
+0.0
+}}}
+{{{#!td
+Scalar exchange coefficient for a leaf (dimensionless).\\\\
+This parameter is only of importance in cases in that both, [#plant_canopy plant_canopy] and [#passive_scalar passive_scalar], are set ''.T.''. The value of the scalar exchange coefficient is required for the parametrisation of the sources and sinks of scalar concentration due to the canopy.
+}}}
+|----------------
+
+