عنوان مقاله [English]
نویسندگان [English]چکیده [English]
In this study, climatic factors statistical trend analysis of rainfall, temperature and drought on seasonal and yearly scales at 15 stations of the Hamadan region, was performed. For this purpose, initially at the level of drought each station standardized precipitation index (SPI) and then calculate the variation factors studied using Kendall nonparametric test was. Average annual rainfall trend analysis showed that 60 percent of stations, the process of reducing precipitation was noticed that the further reduction of spring, winter and summer. Seasonal scale, both in summer and autumn, temperature increase and decrease in spring and winter temperature showed. Trend of increasing droughts similar trend was raining, so that 67 percent of the annual drought of stations increased to 33 percent increase on the station level 0.05 significant. The most significant trends in mean climatic factors studied were observed in summer. The trend in the two stations Ghahavand and Amr Abad for all factors studied in both time scales was significant. These two station receiving values of the, maximum and minimum of rainfall are that significant all climatic factors studied is justifiable.