R-Factor for Alaska

The rainfall-runoff erosivity factor (R-Factor) quantifies the effects of raindrop impacts and reflects the amount and rate of runoff associated with the rain. The R-factor is one of the parameters used by the Revised Unified Soil Loss Equation (RUSLE) to estimate annual rates of erosion. This product is a raster representation of R-Factor derived from isoerodent maps published in the Runoff Estimates for Small Rural Watersheds and Development of a Sound Design method. Volume II. (Fletcher et al., 1977). Lines connecting points of equal rainfall erosivity are called isoerodents. The isoerodents plotted on a map of Alaska were digitized, then values between these lines were obtained by linear interpolation. The final R-Factor data are in raster GeoTiff format at 800 meter resolution in Albers Conic Equal Area,WGS84, WGS84.