climate change assessment in khorasan-e razavi province from 2010 to 2039 using statistical downscaling of gcm output

because of low spatial resolution and simplifications in meteorological processes in global circulation models, they cannot sufficiently simulate the weather, comparing to the regional models; then, spatial and temporal downscaling of the gcm outputs are needed for decreasing errors of the global circulation models. there are two methods of downscaling: statistical and dynamic. weather generator technique is one of popular methods of statistical downscaling. in this study, meteorological parameters of echo-g general circulation models including maximum and minimum temperature, radiation and precipitation were downscaled by a weather generator model of lars-wg in the period of 2010-2039. results show the mean of precipitation will decrease by 9.5 percent; mean temperature will be decreased by 1.5-3.3 degrees in the period under study (2010-2039). thresholds of heavy and extreme rainfalls will increase by 45 and 60 percent respectively. it is calculated that precipitations of cold season will increase by 13 percent with a shift toward the end of cold season. finally, it was found that summer rainfall increases by the amount of 50 percent.