Examining The Trend Of Maximum Temperature In Kohgiluyeh And Boyerahmad Province, Case Study: Dashtroom Region

The process of climate change especially temperature and precipitation change is the most important problem in the territory of environmental sciences. Because human systems such as agriculture, industry and others designed and act based on the climate invariability which those are dependent on climatic variables. The climate changes can be trace largely by studying the trend of temperature. The aim of this research is to study probable deviation of normal maximum temperature in Dashtroom region which is located at a distance of twenty kilometers from yasuj city (the center of Kohgiluyeh and Boyerahmad province). In this study, the maximum temperature data of Dashtroom's climatology station were used during years of 1366 1387. Therewith, Nonparametric method of man-Kendal is used in this study that presence or absence significant trend in temperature changes is examined by use of this method. The extracted results from data analysis showed a significant decrease trend in some of time series which this problem indicated that maximum temperature is decreasing in studied region. While, any significant increase is not confirmed by test. The decreasing trend of maximum temperatures is more in June, July, December and August months, respectively with values of -2/58, -2/4, -2/34 and -2/28 (Man-Kendal statistic) than the other months. Moreover, the most decreasing trend of maximum temperature occurred in the summer whit statistic amount of -2/18 in terms of seasonal series. There is also a decreasing trend in maximum temperature at the annual scale whit statistic amount of -1.97 during period studied. The confidence level of significant changes trend is %95 in all series mentioned above except June (whit confidence level of %99). In other series, the increase or decrease trend in the maximum temperature variations includes sudden and short-term fluctuations.