Static input file

The static input file encompasses topography information as well as all necessary information file to initialize all land- and urban-type surfaces in the model, such as heat capacities, roughness, albedo, emissivity, etc.. The initialization procedure for the surfaces follows a multi-step approach, depending on the given level of detail of each variable as provided in the static input file. In a first step, surfaces are initialized horizontally homogeneous with a bulk classification for each type (e.g. vegetation or soil), either set by a default value or set by a namelist-provided value, while the bulk classification provides standard values for a variety of parameters. In a second step, surfaces are initialized individually by providing the bulk classification at each grid point individually. In case more detailed information is available, all or even single parameters can be initialized individually at each grid point.

The provided input data is used to classify each surface element according to its treatment, i.e. default-, natural- or urban-type, in order to treat each surface element accordingly.

In case no land-surface or urban-surface scheme is applied, all surfaces are classified as default-type. If a surface element has vegetation, pavement or water, it will be classified as natural-type and is treated by the land-surface scheme, while building surfaces will be treated by the urban-surface scheme.

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Global attributes

Attribute	Type	Explanation / Remarks
acronym	NC_CHAR	Abbreviation of institution (max. 12 characters)
author	NC_CHAR	first name, last name, email address
campaign	NC_CHAR	User-defined text, max. 12 characters
contact_person	NC_CHAR	first name, last name, email address
creation_time	NC_CHAR	File creation date (UTC), format: YYYY-MM-DD hh:mm:ss +00
comment	NC_CHAR	User-defined text
Conventions(*)	NC_CHAR	Must be set to "CF-1.7".
data_content	NC_CHAR	User-defined text, max. 16 characters
dependencies	NC_CHAR	User-defined text
history	NC_CHAR	Information of data processing, separation by comma, e.g., "2016-04-22 11:45: updated vegetation"
keywords	NC_CHAR	User-defined list, separated by comma
license	NC_CHAR	User-defined text
location	NC_CHAR	User-defined text
origin_lat(*)	NC_FLOAT	Geographical latitude in degrees north. This attribute defines the south boundary of the model domain and overwrites the namelist parameter latitude, which is used e.g. for the Coriolis parameters as well as for the radiation. Please note, in case of a nested run, values of latitude will be synchronized internally to the respective value of the root parent domain.
origin_lon(*)	NC_FLOAT	Geographical longitude in degrees east. This attribute defines the left boundary of the model domain and overwrites the namelist parameter longitude, which is used e.g. for the radiation. Please note, in case of a nested run, values of longitude will be synchronized internally to the respective value of the root parent domain.
origin_time(*?)	NC_CHAR	Reference point in time (UTC) YYYY­-MM­-DD hh:mm:ss +00.
origin_x(*)	NC_FLOAT	Reference x-location in m (UTM) of left model boundary.
origin_y(*)	NC_FLOAT	Reference y-location in m (UTM) of lower model boundary.
origin_z(*)	NC_FLOAT	Reference height in m above sea level after DHHN2016.
palm_version	NC_FLOAT	e.g. "5.0" for compatibility checks
references	NC_CHAR	User-defined text
rotation_angle(*?)	NC_FLOAT	Clockwise angle of rotation in degrees between North positive y axis and the y axis in the data, e.g. 0.0. This value overwrites the namelist parameter rotation_angle, which is used e.g. to calculate the Coriolis force.
site	NC_CHAR	User-defined text
source	NC_CHAR	User-defined text
title	NC_CHAR	Short description, e.g., "PALM input file for scenario 1b"
version	NC_INT	e.g. "1"

(*) are mandatory attributes

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Grid mapping

Grid mapping is defined via variable crs which is defined as:

Variable	Type	Attributes	Remarks
crs	NC_INT	See list below	Attributes of crs define the grid mapping. It has no dimensions (single integer) and its value does not need to be set.

The following list defines the attributes of the grid-mapping variable crs. Given values are an example of how to define "EPSG:25833" (ETRS89 / UTM zone 33N).

Attribute	Type	Value
long_name	NC_CHAR	"coordinate reference system"
grid_mapping_name	NC_CHAR	"transverse_mercator"
semi_major_axis	NC_CHAR	6378137.0
inverse_flattening	NC_FLOAT	298.257222101
longitude_of_prime_meridian	NC_FLOAT	0.0
longitude_of_central_meridian	NC_FLOAT	15.0
latitide_of_projection_origin	NC_FLOAT	0.0
scale_factor_at_central_meridian	NC_FLOAT	0.9996
false_easting	NC_FLOAT	500000.0
false_northing	NC_FLOAT	0.0
units	NC_CHAR	"m"
epsg_code	NC_CHAR	"EPSG:25833"

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List of attributes

The following list gives an overview of attributes that can be assigned to variables in a static driver file.

Attribute	Type	Value	Description
_FillValue	Variable-specific	Variable-specific	Fill value for missing data
coordinates	NC_CHAR	"E_UTM N_UTM lon lat x y z time"	Coordinate system
flag_meanings	NC_CHAR	Variable-specific	Explanation of the meaning of 0b and 1b for NC_BYTE variables
flag_values	NC_BYTE	0b, 1b	Explanation of the meaning of 0b and 1b for NC_BYTE variables
grid_mapping	NC_CHAR	"crs"	Grid mapping
lod	NC_INT	Variable-specific	Level of detail used for some variables
long_name	NC_CHAR	Variable-specific	Variable long name
res_orig	NC_CHAR	Variable-specific	Resolution of the original data
source	NC_CHAR	Variable-specific	Data source
units	NC_CHAR	Variable-specific	Units of the variable
valid_range	NC_BYTE	0b, 1b	Valid range of values

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List of dimensions

The following list provides an overview of all dimension variables that can be used in a static driver file. All dimensions should start with 0, except for ns, which has to start with 1.

Dimension	Type	Value	Description
nalbedo_pars	NC_INT	8	number of elements in albedo_pars
nbuilding_surface_pars	NC_INT	28	number of elements in building_surface_pars
npavement_pars	NC_INT	4	number of elements in pavement_pars
npavement_subsurface_pars	NC_INT	2	number of elements in pavement_subsurface_pars
ns	NC_INT	-	number of surface elements used in building_surface_pars.
nsoil_pars	NC_INT	8	number of elements in soil_pars
nsurface_fraction	NC_INT	3	number of elements in surface_fraction
nvegetation_pars	NC_INT	12	number of elements in vegetation_pars
nwater_pars	NC_INT	7	number of elements in water_pars

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List of coordinate variables

The following list provides an overview of all coordinate variables that can be used in a static driver file.

Variable	Type	Attributes	Remarks
azimuth	NC_FLOAT	long_name="azimuth angle" units="degrees"	Azimuth angle of surface element (ns) orientation (normal vector)
azimuth_uv	NC_FLOAT	long_name="azimuth angle for uv exposure" units="degrees"	Azimuth angle for obstruction_uv input
Es_UTM	NC_FLOAT	long_name="projection x coordinate" units="m"	Projection of x-coordinate for surface element (ns)
lats	NC_FLOAT	long_name="latitude" units="degrees_north"	Latitude of surface element (ns)
lons	NC_FLOAT	long_name="longitude" units="degrees_east"	Longitude of surface element (ns)
Ns_UTM	NC_FLOAT	long_name="projection y coordinate" units="m"	Projection of y-coordinate for surface element (ns)
x	NC_FLOAT	axis="X" long_name="distance to origin in x-direction units="m"
xs	NC_FLOAT	axis="X" long_name="distance to origin in x-direction units="m"	Distance of origin to building surface element (ns) in x-direction
y	NC_FLOAT	axis="Y" long_name="distance to origin in y-direction units="m"
ys	NC_FLOAT	axis="Y" long_name="distance to origin in y-direction units="m"	Distance of origin to building surface element (ns) in y-direction
z	NC_FLOAT	axis="Z" long_name="height above origin" positive="up" standard_name="height_above_mean_sea_level" units="m"
zs	NC_FLOAT	axis="Z" long_name="height above origin" positive="up" standard_name="height_above_mean_sea_level" units="m"	Height above origin of building surface element (ns)
zenith	NC_FLOAT	long_name="zenith angle" units="degrees"	Zenith angle of surface element orientation (normal vector)
zenith_uv	NC_FLOAT	long_name="zenith angle for uv exposure" units="degrees"	Zenith angle for obstruction_uv input
zlad	NC_FLOAT	axis="Z" long_name="height above ground" positive="up" units="m"	z-location in m above the ground for mapping vegetation, used in lad, bad, and tree_id
zsoil	NC_FLOAT	axis="Z" long_name="depth in the soil" positive="down" units="m"	z-location in m within the soil (positive downward), used in soil_type

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Topography set-up

In order to prescribe topography from the static input file, topography = 'read_from_file' is required.

Input variable	Type	Attributes	Explanation / Remarks
building_id(y,x)	NC_INT	_FillValue=-9999(*) coordinates grid_mapping long_name="building id number" res_orig source units="1"	The building ID is used to identify single building envelopes which are composed of a number of grid volumes, and which is used for correct mapping of buildings on top of the underlying terrain, as well as for the indoor_model. Please note, building_id must not contain any _FillValue at grid points where buildings are is defined via building_2d or building_3d. There is no specification or limitation for the ID numbers, except that each building must have a unique number.
buildings_2d(y,x)	NC_FLOAT	_FillValue=-9999.f(*) coordinates grid_mapping lod=1 long_name="building height" res_orig source units="m"	Two-dimensional building height in m relative to the underlying terrain. No holes or overhanging structures are possible. buildings_2d will be mounted on top of the maximum local terrain height occupied by the respective building. Please note, buildings_2d will not be used if buildings_3d is present on file. If buildings_2d is used building_id is required.
buildings_3d(z,y,x)	NC_BYTE	_FillValue=-127b(*) coordinates flag_meanings="no building, building" flag_values=0b, 1b grid_mapping long_name="building flag" res_orig source units="1" valid_range=0b, 1b	Three-dimensional building topology relative to the underlying terrain. buildings_3d will be mapped on top of the maximum local terrain height occupied by the respective building. Note, buildings_3d does not need to be prescribed beyond the top level of the highest buildings, i.e. z dimension can me minimized accordingly. If buildings_3d is prescribed, building_id is required.
obstruction_uv(azimuth_uv,zenith_uv,y,x)	NC_BYTE	_FillValue=-127b(*) coordinates flag_meanings="no obstruction, obstruction" flag_values=0b, 1b grid_mapping long_name="obstruction" res_orig source units="1" valid_range=0b, 1b	Obstruction of the sky at a pixel location (y,x). This field is needed only if the UV exposure model is used.
zt(y,x)	NC_FLOAT	_FillValue=-9999.f(*) coordinates grid_mapping long_name="terrain height" res_orig source units="m"	Terrain height in m relative to origin_z. If not provided, the relative terrain height will be set to 0 m all over the model domain. Please note, zt must not contain any _FillValues.
z0(y,x)	NC_FLOAT	_FillValue=-9999.f(*) coordinates grid_mapping long_name="roughness length for momentum" res_orig source units="m"	Roughness length for momentum. Note that input of z0 is only useful for default-type surfaces, i.e., for simulations without land surface model and urban surface model.

(*) are mandatory attributes

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Main surface classification

For a proper classification of natural land and water surfaces, pavement_type, soil_type, vegetation_type and water_type are required, which define bulk parameters for albedo, soil, root distribution, leaf-area density, etc. To enable initialization of the land-surface model with input-file-provided variables, the namelist parameter surface_type needs to be set to 'netcdf'. In case more than one of the surface types (vegetation, pavement, water) is given at an (x,y) location, the relative fraction of each of the types must be provided by surface_fraction.

Further, if the urban-surface model is applied, also building_type is required, which defines bulk parameters to run the urban-surface model. Please note, for the sake of consistency, at least one of the variables pavement_type, vegetation_type, water_type or building_type needs to be defined at each (y,x) location if the land- and urban-surface model is applied.

If only the land-surface model is applied but no urban-surface model, one of pavement_type, vegetation_type or water_type needs to be defined at each (y,x) location.

Input variable	Type	Attributes	Explanation / Remarks
albedo_type(y,x)	NC_BYTE	_FillValue=-127b(*) coordinates grid_mapping long_name="albedo type classification" res_orig source units="1"	Optional classification of albedo. Default values for albedo_type are already set in the bulk parametrization of building_type, pavement_type, vegetation_type, water_type, but will be overwritten in case albedo_type is defined. The value of albedo_type will also overwrite the prescribed values in vegetation_pars, water_pars, or pavement_pars. For details, see albedo_type. albedo_type Description 0 user defined according to albedo_pars 1 ocean 2 mixed farming, tall grasslannd 3 tall/medium grassland 4 evergreen shrubland 5 short grassland / meadow / shrubland 6 evergreen needleleaf forest 7 mixed deciduous forest 8 deciduous forest 9 tropical evergreen broadleaved forest 10 medium/tall grassland / woodland 11 desert, sandy 12 desert, rocky 13 tundra 14 land ice 15 sea ice 16 snow 17 bare soil 18 asphalt/concrete mix 19 asphalt (asphalt concrete) 20 concrete (Portland concrete) 21 sett 22 paving stones 23 cobblestone 24 metal 25 wood 26 gravel 27 fine gravel 28 pebblestone 29 woodchips 30 tartan (sports) 31 artifical turf (sports) 32 clay (sports)
building_type(y,x)	NC_BYTE	_FillValue=-127b(*) coordinates grid_mapping long_name="building type classification" res_orig source units="1"	Building type used to select bulk parameters. building_type is required if the urban-surface model or the indoor_model are applied. Please note, building_type must not contain any _FillValue at grid points where buildings_2d / buildings_3d is defined. For details, see building_type. pavement_type(y,x) NC_BYTE _FillValue=-127b(*) coordinates grid_mapping long_name="pavement type classification" res_orig source units="1" Bulk classification of pavements on soil. At locations where pavement_type is defined, soil_type must not contain any _FillValues. pavement_type overwrites the homogeneously prescribed setting via the namelist parameter pavement_type. soil_type((zsoil,)y,x) NC_BYTE _FillValue=-127b(*) coordinates grid_mapping lod long_name="water type classification" res_orig source units="1" Bulk classification of soil in terms of porosity. soil_type overwrites the homogeneously prescribed setting via the namelist parameter soil_type. A soil type is need at all locations where either a vegetation_type or a pavement_type is set. In case lod = 1, a 2-dimensional vertically uniform soil texture is prescribed, while in case lod = 2 the 3-dimensional soil_type is set for each layer individually. For details, soil_type. street_crossing(y,x) NC_BYTE _FillValue=-127b(*) coordinates grid_mapping long_name="street type classification" res_orig source units="1" valid_range=1b Localization of street crossings that can be used by pedestrians (traffic lights, zebra crossings, crosswalks). The only valid number is 1b. street_crossing will be required for application of the multi-agent system in near future. street_type(y,x) NC_BYTE _FillValue=-127b(*) coordinates grid_mapping long_name="street type classification" res_orig source units="1" Classification of streets, closely following the Open Street Map classification. street_type is required for application of the parameterized traffic emissions (see emission mode LOD 0 here) and for the multi-agent system. street_type Description 1 unclassified 2 cycleway 3 footway / pedestrian 4 path 5 track 6 living street 7 service 8 residential 9 tertiary 10 tertiary link 11 secondary 12 secondary link 13 primary 14 primary link 15 trunk 16 trunk link 17 motorway 18 motorway link 19 raceway surface_fraction(nsurface_fraction,y,x) NC_FLOAT _FillValue=-127b(*) coordinates grid_mapping long_name="water type classification" res_orig source units="1" Relative fraction of the respective surface type given via vegetation_type (nsurface_fraction = 0), pavement_type (nsurface_fraction = 1) and water_type (nsurface_fraction = 2). The sum over all relative fractions must be equal to one for each location. This parameter is only needed at locations (y,x) where more than one surface type (vegetation, pavement, water) is defined. Moreover, if more than one surface type is defined at a location, the relative fractions of the respective surface types must not be 0. Also, if surface_fraction is given for one of the above mentioned surface types, this type need to be defined at this location. vegetation_type(y,x) NC_BYTE _FillValue=-127b(*) coordinates grid_mapping long_name="vegetation type classification" res_orig source units="1" Bulk classification of non-resolved (i.e. flat) vegetation surfaces at natural land surface types. At locations where vegetation_type is defined, soil_type must not contain any _FillValues. vegetation_type overwrites the homogeneously prescribed setting via the namelist parameter vegetation_type. vegetation_type Description albedo_type 0 User_defined according to vegetation_pars 1 bare soil 17 2 c rops, mixed farming 2 3 short grass 5 4 evergreen needleleaf trees 6 5 deciduous needleleaf trees 8 6 evergreen broadleaf trees 9 7 deciduous broadleaf trees 8 8 tall grass 3 9 desert 11 10 tundra 13 11 irrigated crops 2 12 semidesert 11 13 ice caps and glaciers 14 bogs and marshes 4 15 evergreen shrubs 4 16 deciduous shrubs 4 17 mixed forest/woodland 7 18 interrupted forest 8 water_type(y,x) NC_BYTE _FillValue=-127b(*) coordinates grid_mapping long_name="water type classification" res_orig source units="1" Bulk classification of water bodies. water_type overwrites the homogeneously prescribed setting via the namelist parameter water_type. water_type Description albedo_type 0 user defined 1 1 lake 1 2 river 1 3 ocean 1 4 pond 1 5 fountain 1 Pixel-based surface and sub-surface parameters While the *_type classification will set all required surface and sub-surface parameters automatically, the *_pars variables listed below allow for overwriting single or multiple parameters at single or multiple pixel locations (y,x). The use of these variables is optional. Variable Type Attributes Explanation / Remarks albedo_pars(nalbedo_pars,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="albedo parameters" res_orig source Pixel-specific settings for surface albedo. Must be set when albedo_type = 0. For details, see albedo_pars. building_pars(nbuilding_pars,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="building parameters" res_orig source Pixel-specific settings for buildings. Must be set when building_type = 0. For details, see building_pars. pavement_pars(npavement_pars,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="pavement surface parameters" res_orig source Pixel-specific settings for pavement surfaces. Must be set when pavement_type = 0. For details, see pavement_pars. pavement_subsurface_pars(npavement_subsurface_pars,zsoil,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="pavement subsurface parameters" res_orig source Pixel-specific settings for pavement sub-surface properties. Must be set when pavement_type = 0. For details, see pavement_subsurface_pars. water_pars(nwater_pars,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="water parameters" res_orig source Pixel-specific settings for water bodies. Must be set when water_type = 0. For details, see water_pars. (*) are mandatory attributes Vegetation parameters The vegetation_type will set bulk properties for unresolved vegetation, i.e., vegetation that is considered to be flat. For high vegetation such as trees, the canopy model can be used to prescribe resolved vegetation, i.e., vegetation that is represented by multiple grid volumes. The following list gives an overview of the vegetation variables that can be set to represent three-dimensional vegetation. Attention: From the following list, PALM only uses the leaf area density, while the other variables are ignored at the moment. Variable Type Attributes Explanation / Remarks lad(zlad,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="basal area density" res_orig source units="m2 m-3" Vegetation resolved by the canopy model in terms of a three-dimensional leaf area density (LAD). The dimension zlad can be limited to the maximum canopy height. lad(zlad,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="basal area density" res_orig source units="m2 m-3" Basal area density (BAD) in m² per m³ grid volume, representing trunk an branches within the respective grid volume. The dimension zlad can be limited to the maximum canopy height. root_area_dens_r(zsoil,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="root area density of resolved vegetation" res_orig source units="1" Root area of resolved vegetation, provided via an LAD field, in the soil. root_area_dens_s(zsoil,y,x) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="root area density of parameterized vegetation" res_orig source units="1" Root area of parameterized (i.e. flat) vegetation, treated by the land surface model. tree_id(y,x) NC_INT _FillValue=-9999 (*) coordinates grid_mapping long_name="tree id" res_orig source units="1" ID of the tree which belongs to the specific grid volume. Surface-based building parameters While the *_pars variables allow only to overwrite settings for buildings at location (y,x), the surface-based building parameters allow for overwriting properties of individual surface elements. The use of these variables is optional. Variable Type Attributes Explanation / Remarks building_surface_pars(nbuilding_surface_pars,ns) NC_FLOAT _FillValue=-9999.f (*) coordinates grid_mapping long_name="building surface parameters" res_orig source Settings for individual building surfaces. For details, see building_surface_pars. Example static driver file An example static driver file can be downloaded here (built for PALM r4311). This file was produced using palm_csd​ using the configuration file .csd.config.example, and which is based on pre-processed input data for Berlin, Germany. Provided the availability of this data set, the static driver should be able to be reproduced (after small adjustments in the configuration file) via the command: palm_csd .csd.config.example Snapshot of building heights in example static driver file (using ncview) ncdump of the static driver file header