DOWNSCALING 2 VERSIONS OF A GENERAL-CIRCULATION MODEL TO ESTIMATE LOCAL HYDROCLIMATIC FACTORS UNDER CLIMATE-CHANGE

The regional hydroclimatological effect of global climate change has b een estimated and compared using a semi-empirical downscaling method w ith two versions (T21 and T42) of the general circulation model (GCM) developed at the Max Planck Institute for Meteorology, Germany. The co mparisons were performed with daily mean temperature and daily precipi tation amounts for the continental climate of the state of Nebraska, U SA. Both the T21 and the T42 versions resulted in an increase of daily mean temperature under a 2 x CO2 climate. The magnitude of warming wa s substantially greater for T21 than for T42, except for February and June and at some stations in July where the T42 model suggested greate r warming. Both GCMs resulted in a slight decrease in precipitation fr equency and an increase in the amount of precipitation on wet days. He re, the T42 model again led to smaller changes. Different locations wi thin Nebraska exhibited somewhat different temperature and precipitati on responses with both GCM versions.