Application of the National Hydrologic Model Infrastructure with the Precipitation-Runoff Modeling System (NHM-PRMS), Uncalibrated Version

This data release contains output and components of the initial conterminous United States (CONUS) application of the Precipitation-Runoff Modeling System (PRMS) as implemented in the National Hydrologic Model (NHM) infrastructure (Regan et al, 2018). The PRMS version 5.0.0 hydrologic simulation code was used with the accompanying parameter files in the NHM infrastructure to produce the attached output files. Model input climate drivers include climate data derived from the Daymet gridded data set version 2 (Thornton et al., 2014) with values spatially-distributed to the HRUs using the USGS Geo Data Portal (https://cida.usgs.gov/gdp/; Blodgett et al., 2011). The parameter values are maintained in the National Hydrologic Model Parameter Database (NhmParamDb; Driscoll et al., 2017). Parameter values for all but the initial snowpack water equivalent (parameter snowpack_init) and snow depletion curves (parameters hru_deplcrv and snarea_curve) from the NhmParamDb were used, the parameter file used to produce these model results is attached (NHM-PRMS.zip). The initial snowpack water equivalent was set to zero and a single default depletion curve was used for all hydrologic response units (HRUs).

The NHM-PRMS simulations were conducted with the same configuration for a time period from October 1, 1990 to December 31, 2016. The first three years of the simulations are considered model spin up and not included in the output files. Thus, the output files have a time period of October 1, 1993 to December 31, 2016. Eighty-eight variables were selected to generate individual *.csv files. These file names follow a naming convention of using an abbreviation for the spatial dimension of the model output (nhru or nsegment) _variable name.csv. The variable names included are defined further in Table 1, attached. The structure of each output file includes a header line which labels the columns by the spatial unit (hru or stream segment) identification number and each row has the date followed by either 109951 or 56460 values, depending the output variable dimension nhru or nsegment, respectively. See table 1-10 in Regan and LaFontaine (2017) for a description of the variables included in this file. To distribute parameter and output values spatially, a join can be completed by using the nhru_ID or nseg_ID from the variable and the hru_ID from the national-extent Geospatial Fabric.