Trend Analysis of Precipitation and Temperature Indices over Iran

فاقد چكيده فارسي

Precipitation and temperature are two of the most important climate components that affect water consumption and supply. In this paper, potential trends in 27 climate indices over Iran are calculated andanalyzed by Mann-Kendall and Linear trend analysis methods. The Asfezari dataset used in this research includes daily based gridded data of minimum, maximum, mean daily temperature, and daily precipitation. Spatial resolution of the data set is 15 by 15 kilometer and it covers the time period of 1961to 2004. The analysis shows that during the past four decades, there have been significant increases inthe temperature indices, particularly indices associated with minimum temperature, in vast parts of Iran. However, the results for precipitation indices are a bit more complicated. While most parts of the country do not experience significant changes in annual precipitation, there has been a considerable increase anddecrease in annual precipitation of western and northern part of Iran, respectively. The analys on Middle East indicates that similar climatic condition is dominant over the whole region. If the current climate trends continue, Iran will face warmer and warmer climate which associates with lesser and lesser available water. So, it seems that thewater crisis is not a temporary issue resulted by some consecutive droughts