Evaluating eolian-climatic interactions using a regional climate model from Hanford, Washington (USA)

A regional climate model (RCM) developed for the Hanford Site, Washington illustrates a potentially useful method for assessing eolian responses to regional climate change. The RCM is based on long-term relations between fundamental climatic variables of precipitation, temperature, and wind speed. Modelled data are integrated into eolian-climatic scenarios through maps of eolian susceptibility, plots of sand dune mobility, and calculated trends of unvegetated dune sand volumes. Results demonstrate the sensitivity of eolian-climatic interactions to small changes in precipitation. es suggest that continuation of the 1977–1987 trend toward a cooler (−0.16°C) and wetter (+1.8 cm yr−1) climate over the next 10–15 years will result in a decrease of ∼18% in the volume of unvegetated dune sand. Further temperature reductions totaling 0.7°C would promote precipitation increases of 30% leading to an additional reduction of 98% in the volume of unvegetated dune sand. Modelling scenarios for a possible global warming of +4°C indicate that annual precipitation at Hanford would be negligible and vegetation would be eliminated from dune surfaces. Sand dune mobility would increase by over 400%.