i. babaeian

The impact of climate change on precipitation and temperature changes by climate predicted models analyzed. General circulation models of the atmosphere and subsequent use of subscale models such as LARSWG5 make it possible، but these predictions are encountered with uncertainty. In this study، the investigation of uncertainty output of LARS-WG5 model after the forecasting of two parameters of precipitation and temperature over thirty years also studied، from 2041 to 2012 in synoptic station of Mashhad. The results showed that the output of this subscale model does not have certainty، as the amounts of subscale precipitation in the first and fourth quartiles are different in Mashhad station. Through using A2 Scenario and three models of HadCM3، GFCM21 and INCM3 in the first quartile، 75% of the predicted rainfall respectively، over 53. 95، 57. 17 and 44. 93 mm in March، and in the third quartile، 25 percent of the data respectively are greater than 59. 86، 63. 53 and 50. 23 mm.