Implementation of WEPS 1.0 within NRCS.

The Wind Erosion Prediction System (WEPS) is a process based, daily time step, wind erosion model. It was conceived to replace the empirical Wind Erosion Equation (WEQ), first released in 1965 to better reflect management effects on the susceptibility of soil to wind erosion.  Besides providing predictions on the long-term annual soil loss from cropland fields, WEPS can provide estimates by particulate size (creep/saltation, suspension and PM10) leaving the simulation site as well as the impact of wind barriers and changes in surface conditions created by different management practices. It simulates the daily changes due to weather on surface roughness and soil wetness, residue decomposition, plant growth, etc. and therefore reflects the overall impact of weather variations on the susceptibility to wind erosion on a year by year basis. USDA-NRCS (Natural Resources Conservation Service) is in the process of implementing WEPS as a replacement for WEQ.  As such, they required databases for weather inputs (precipitation, temperature, solar radiation, etc.), wind, soil and management practices to run the model for agricultural cropland nationally. In addition, database records for all prominent crops and operations (tillage, planting, harvesting, etc.) were required as well. Since the model will be run in NRCS field offices, ease of use and minimal runtime requirements were also issues that had to be adequately addressed before implementation could begin within their agency.