Modeled areal evaporation trends over the conterminous United States

Long-term (1961-1990) areal evapotranspiration (AE) has been modeled with t he help of 210 stations of the Solar and Meteorological Surface Observation Network within the conterminous United States. Modeled AE, averaged over a ll stations, has shown an overall increase of about 2-3% in the period 1961 -1990, both on an annual basis and over the warm season (May-September). Th e rate of increase has differed among three geographic regions: the eastern , central, and western United States, with the largest modeled increase fou nd in the east, followed by the central part of the United States. In the w estern part of the continent, modeled AE has, in fact, stayed constant. Of these trends, only the ones over the eastern part of the conterminous Unite d States are statistically significant.