Routing Model Parameters¶

Note

It is the user's responsibility to ensure that parameter files are formatted appropriately. Notably, the variables uh_runoff and uh_inflow must sum exactly to 1.0.

The Routing Parameters serve three main purposes:

Define the cell ID number of each grid cell. This ID number is used to identify downstream cells.
Define the downstream cells
Define the unit-hydrographs.

The routing parameters are supplied to VIC-WUR in a NetCDF file, with a separate variable for each routing parameter.

Below is a list of routing parameters.

Variable Name	Dimension	Units	Type	Number of Values	Description
downstream_id	[lat, lon]	N/A	int	1	Current cell grid cell ID
downstream	[lat, lon]	N/A	int	1	Downstream cell grid cell ID
uh_runoff	[time, lat, lon]	fraction	double	routing max length	Convolution fraction for runoff
uh_inflow	[time, lat, lon]	fraction	double	routing max length	Convolution fraction for inflow

Example netCDF format VIC-WUR image driver routing parameters¶

netcdf rout_params_global {
dimensions:
    lon = 720 ;
    lat = 360 ;
    time = 48 ;
variables:
    double lon(lon) ;
        lon:units = "degrees_east" ;
        lon:long_name = "longitude of grid cell center" ;
    double lat(lat) ;
        lat:units = "degrees_north" ;
        lat:long_name = "latitude of grid cell center" ;
    float downstream_id(lat, lon) ;
        downstream_id:units = "ID" ;
        downstream_id:_FillValue = -1.f ;
        downstream_id:long_name = "ID used to identify downstream cell" ;
    float downstream(lat, lon) ;
        downstream:units = "ID" ;
        downstream:_FillValue = -1.f ;
        downstream:long_name = "ID of the downstream cell" ;
        downstream:Description = "Unit hydrograph generated based on Lohmann et al (1996) with flow velocity 1 [m s-1] and diffusion 2000 [m s-2]" ;
    double time(time) ;
        time:units = "seconds" ;
        time:long_name = "Time in the unit hydrograph" ;
    float uh_inflow(time, lat, lon) ;
        uh_inflow:units = "[-]" ;
        uh_inflow:_FillValue = -1.f ;
        uh_inflow:long_name = "Unit hydrograph of the inflow (river)" ;
    float uh_runoff(time, lat, lon) ;
        uh_runoff:units = "[-]" ;
        uh_runoff:_FillValue = -1.f ;
        uh_runoff:long_name = "Unit hydrograph of the runoff (cell)" ;

// global attributes:
        :Description = "Routing parameters for VIC. Created by Bram Droppers" ;
}