Distributed HMET Data

The main benefit of using distributed hydrometeorology (HMET) data in GSSHA is that the entire model does not have to use the same hourly data values throughout the entire domain. The temperature, cloud cover, direct radiation, global radiation, pressure, relative humidity, and wind speed can be spatially varied over the entire model domain. This is more realistic than assuming the entire domain has the same uniform hourly values for these data. Precipitation data can also be input into the GSSHA model using Arc/Info ASCII grids of rainfall, as shown in http://www.gsshawiki.com/gssha/Precipitation:Spatially_and_Temporally_Varied_Precipitation.

Currently, if one piece of data is input in raster form, all data must be input in raster form. This means that if temperature data is input in a Arc/Info ASCII grid, all HMET data must be input in the same form. Below is shown how to input distributed HMET Data into the GSSHA model.

Distributed HMET Input Card - Optional

Card	Argument	Units	Description
HMET_ASCII ***.txt	File	see below	Inputs hyrometeorology data (temperature, cloud cover, direct radiation, global radiation, pressure, relative humidity, and wind speed) in each cell based on hourly Arc/Info ASCII grid files, giving the model more spatial variability. The files must have a specific format as described below.