Etection of Climate Change with Extreme Temperature indices in great Khorasan

Climate change with changing climate patterns and confounds Ecosystems discipline, imports Serious consequences on the environment. Changes in weather patterns Could Lead to severe flooding, extreme heat or cold, more frequent droughts. Each of these phenomena could put at risk the regional food reserves. North east of Iran due to the large area has very varied natural conditions and each of the areas included specific natural features. The extent of the area and factors such as mountains rising, desert areas. In this research, were use 25 year synoptic meteorological stations (14 stations) statistics from1/1/1987 to 31/12/2011? Result show that some station such an Ghochan and Sabzevar, show an decrease trend in the number of extreme temperature indices (CSDI, TR20,TNX,FD,TN10P). Other stations, in 90%, experience increase extreme temperature changes. Among the indicators, in the first order; the days of Summer, the warm days, The maximum temperature limit, the warm nights, the warm period duration Indicators Show an increase of 100% and cold days index shows an decreas of 100%. Also the minimum temperature of at least, maximum temperature of at least and tropical night indicators by more than 85% increasing trend and the cold night index by more than 85% are In second place. The maximum temperature of at least and the growing season duration indicators with 71% and 69% increasing trend and the ice days index with 71% decreasing trend, are In the third place. Hence we can derive the great Khorasan experience sever increasing temperature changes in last 25 years and based on behavior of indices, severity of this changes in coming decades will be multiple.