Hazard Assessment of Climate Changes in South Khorasan Province, Iran

Abstract

In the present research to assess past climate change trend and its severity in South Khorasan province located in the east of Iran, the climatic parameters included annual precipitation and annual average of temperature data for 10 meteorological stations over the study area during a study period of 23 years from 1989 to 2012 were analyzed using linear regression analysis and Pearson correlation coefficient. Similarly in order to analyze the temporal fluctuations of dry and humid periods over the study area, three and five years moving average graphs were also prepared. Based on the results of temperature analysis 93% of the extent of the region has become warmer than before, while 7% has no significant changes in the temperature trends. The precipitation in 51% of the extent of the region has been decreased and 49 % of the land doesn’t show any significant changes. Also about climate change in the region using trends of De Martonne index, 76% of the extent of the region has become drier than before, while 24% of the region doesn’t show any significant changes. Similarly regarding the applied hazard classification for climate change based on the trends of temperature and aridity index of De Martonne , a great proportion (69%) of land is under very severe hazard in region, and the rest (31% of the land area) was classified under severe hazard. This contribution provides evidence demonstrating intensity of drought during the last two decades in the study area.

Keywords

• Climate change, De Martonne index, Hazard class, Moving Average