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The Revised Universal Soil Loss Equation, Version 2 (RUSLE2), provides robust estimates of average annual sheet and rill erosion for one-dimensional hillslope representations. Extensive databases describing climate, soils, and management options have been devel-oped and are widely used in the United States for conservation planning. Recent RUSLE2 enhancements allow estimation of erosion and runoff from a representative sequence of run-off events that are suitable for linkage with an ephemeral gully model. This paper reviews the sensitivity of RUSLE2 erosion estimates to possible climate change scenarios, demonstrates its ability to evaluate alternative management adaptations, and compares predictions with observations of runoff and sediment yield from a 6.6 ha (16 ac) research watershed located near Treynor, Iowa. When applied to a representative hillslope profile with conventional tillage corn (Zea mays L.), increasing monthly temperature by 0.8°C (1.5°F) and rainfall depth, rain-fall erosivity density, and 10-year, 24-hour rainfall depth each by 10% cumulatively increased sheet and rill erosion by 47% and increased runoff by 33%, assuming there was no change in corn yield. If the climate changes decreased corn yield by 10%, the overall effect was to increase soil loss for conservation planning by 63%.These results demonstrate that modest and expected changes in climate will significantly increase the risk of soil erosion, and improved conservation management will be an important part of successful adaptation. [ABSTRACT FROM AUTHOR]

Impacts of climate change on natural resources need to be evaluated in a range of geography and agricultural systems for better conservation planning. The objectives of this paper were to evaluate spatial sensitivity of predicted soil loss and runoff to climate change at large scales, and to simulate the ‘regional’ impacts of climate change on soil erosion on the southern Great Plains. Relative climate changes at three spatial scales between 1950 to 99, and 2070 to 99, projected using HadCM3 under the A2a, B2a, and GGa1 emission scenarios, were used to generate changed climates for Chickasha, Oklahoma. The Water Erosion Prediction Project (WEPP) model was run for each climate scenario at three spatial scales with three tillage systems. The HadCM3 predicted a general decrease in precipitation and an increase in the east-west precipitation gradient on the Southern Great Plains over the century. The decrease in precipitation resulted in general decreases in predicted runoff and soil loss. Percent changes, compared to the present climate, ranged from -33 to -3 percent for runoff and from -33 to 0 percent for soil loss. Variability of predicted runoff and soil loss over spatial scales was comparable to that between climate change scenarios. This finding suggests that the climatic impacts should be assessed at the spatial resolution at which global climate models have predictive skill, or at multiple spatial scales if the skillful resolution is unknown. The latter would yield additional information on uncertainty of predicted impacts due to uncertainty of spatial scales of climate input. [ABSTRACT FROM AUTHOR]