Potential changes in rainfall erosivity under climate change from multi-scenario projections in Southern Appalachian region

The potential change in rainfall erosivity, RUSLE R-factor, in the southern Appalachian region, north of Knoxville in Tennessee, is investigated under three future climate change scenarios A1F1, A1B and B1. Data from CCSM global circulation model (GCM) is used for this investigation by spatial temporal statistical downscaling techniques. R-factors for future dates (2011-2099) are estimated by spatial downscaling of monthly precipitation data obtained from CCSM model and then temporally downscaled to produce daily weather series by means of a stochastic weather generator, CLIGEN. The CLIGEN was calibrated first by the rainfall data for the period 1959 to 1999 and then used to produce future rainfall amounts and patterns. Different comparisons were made between R-factors produced based on different future climate change scenarios. Results from this study can widely be used to assess potential future soil erosion conditions in this area, and the extent how effective current best management practices (BMP) may be in reducing soil erosion and sediment delivery. The same method and technique is applicable for other regions of interest. © 2011 ASCE.