Spatial and seasonal pattern in climate change, temperatures across Iran

The present study is mainly concerned with the changing trend of temperature of Iran based on NCEP data from atmospheric general circulation model under A1B scenario. The date were divided into two periods 1961-1990 and 1991-2050 and for each periods، modified Mann-Kendall test have been used together with the Sen’s Slope Estimator for the determination of seasonal trend and slope magnitude، then the resulting values for each grid point of atmospheric general circulation model network were classified The result showed that in the first period، trend were detected only in summer and winter seasons in some area but in the second period، trend were detected in all of season and area. Also slope of train line were greatest in summer and smallest in winter and this gradient in west and southwest of Iran greater than other area. Keywords: Sen’s Slope Estimator، Air Temperature، Trend، General Circulation Model، Modified Mann-Kendall.