THE PRECIPITATION RUNOFF MODELING SYSTEM: CURRENT AND FUTURE CAPABILITIES

The need to assess the effects of variability in climate, vegetation, geology, and human activities on water availability and movement requires computer models that simulate the hydrologic cycle at a watershed scale. This presentation describes the most recent version of the Precipitation-Runoff Modeling System (PRMS-2010). PRMS-2010 is a modular-design, deterministic, distributed-parameter modeling system developed to evaluate the effects of precipitation, climate, and land use on streamflow and general basin hydrology. The primary objectives of PRMS-2010 are: (1) simulate land-surface hydrologic processes including evapotranspiration, runoff, infiltration, and interflow estimated by balancing energy and water budgets of the plant canopy, snowpack, soil zone and saturated groundwater system on the basis of distributed climate inputs (temperature, precipitation, and solar radiation); (2) predict hydrologic water budgets at the watershed scale with temporal scales ranging from days to centuries; (3) integrate with models used for natural resource management or other scientific disciplines; and (4) provide a modeling system with a modular design that allows for selection of alternative hydrologic process algorithms. In addition, PRMS-2010 will be an important part of the USGS National Hydrologic Model by providing a single system capable of simulating hydrologic processes from coarse to fine spatial resolutions with a wide range of temporal resolutions.