WPS configuration

All modifications discussed here are merged into the github repository wps-wur.

The static 2-D geographic data for use in WRF is prepared by geogrid.exe, a subprogram of the WPS part of WRF. Here, we need to include the FRC_URB2D and the URB_PARAM variables in the geo_em files. Because of the high resolution of the two datasets, for most WRF domains we will need to reduce (instead of interpolate) the data. A reasonable way to do this is to take the WRF grid-cell average.

The urban data has been prepared (in units and missing values) that allow a simple area average. As the URB_PARAM dataset is tiled, we have a lot of points on the edge of a tile where the gridcell average and the four point bilinear interpolation will not work. For those points we do a nearest neighbour search. We also would like to use the high resolution landuse and soil top classification map where it is available (remember it only covers the Netherlands). This can be achieved by using the priority option.

Add the folling sections to the GEOGRID.TBL file:

===============================
name=URB_PARAM
        priority=1
        dest_type=continuous
        fill_missing = 0.
        z_dim_name=num_urb_params
        interp_option=   default:average_gcell(1.0)+four_pt+search
        abs_path=        default:/home/jiska/wrfinput/myurb
===============================
name=FRC_URB2D
        priority=1
        dest_type=continuous
        fill_missing = 0.
        interp_option=default:average_gcell(1.0)+four_pt
        abs_path=     default:/home/jiska/wrfinput/urbanfraction
===============================

For the landuse section we use the priority option to define two maps for the same parameter, with the high-resolution map having a higher priority:

===============================
name=LANDUSEF
        priority=2
        dest_type=categorical
        z_dim_name=land_cat
        landmask_water = wur-landuse:16            # Calculate a landmask from this field
        landmask_water =     default:16            # Calculate a landmask from this field
        dominant=LU_INDEX
        interp_option =  wur-landuse:nearest_neighbor
        interp_option =      default:four_pt
        fill_missing = 7
        abs_path= wur-landuse:/home/jiska/wrfinput/landuse
        rel_path=     default:landuse_2m/
===============================
name=LANDUSEF
        priority=1
        dest_type=categorical
        z_dim_name=land_cat
        landmask_water =     default:16            # Calculate a landmask from this field
        interp_option =      default:four_pt
        rel_path=     default:landuse_2m/
===============================

The same trick is used for the soil top layer classification:

===============================
name=SOILCTOP
    priority=2
    dest_type=categorical
    z_dim_name=soil_cat
    dominant=SCT_DOM
    interp_option = wur-landuse:nearest_neighbor
    interp_option =     30s:nearest_neighbor
    interp_option =      2m:four_pt
    interp_option =      5m:four_pt
    interp_option =     10m:four_pt
    interp_option = default:four_pt
    abs_path=       wur-landuse:/home/jiska/wrfinput/soiltype_top_wur
    rel_path=     30s:soiltype_top_30s/
    rel_path=      2m:soiltype_top_2m/
    rel_path=      5m:soiltype_top_5m/
    rel_path=     10m:soiltype_top_10m/
    rel_path= default:soiltype_top_2m/
===============================
name=SOILCTOP
    priority=1
    dest_type=categorical
    z_dim_name=soil_cat
    interp_option =     30s:nearest_neighbor
    interp_option =      2m:four_pt
    interp_option =      5m:four_pt
    interp_option =     10m:four_pt
    interp_option = default:four_pt
    rel_path=     30s:soiltype_top_30s/
    rel_path=      2m:soiltype_top_2m/
    rel_path=      5m:soiltype_top_5m/
    rel_path=     10m:soiltype_top_10m/
    rel_path= default:soiltype_top_2m/
===============================