Page - 629 - in Book of Full Papers - Symposium Hydro Engineering

is effective and approximately 25 to 40 percent of the principal reasons (Hassanzadeh, 2011). Since many of the data in the actual situation are skidding and do not have normal distribution, therefore, in order to achieve more appropriate result, it is preferred that nonparametric tests, such as Man-Kendal test, which is one of the most widely used and nonparametric methods, be applied to analyze the time- series process (Fujihara, 2016; Modarres, 2009). In studies by Shokoohi et al. (2014), in order to investigate the occurrence of climate change at the 2nd level of the country, it was concluded that in contrast to the decrease of surface currents, the temperature throughout the country has been increasing. In surveys conducted by Nikghoojaghand Yarmohamadi (2008), to investigate the occurrence of climate change in the Sub-basin of Ziyarat River from Gharehosu basin in Golestan Province, was found that the Mean temperature increased. Shokoohi and Daneshkar arasteh (2008)in surveys conducted to investigate the occurrence of climate change throughout the country, concluded that precipitation in some parts of the country was declining, in some sections stable, and in some others, had an increasing trend, but temperatures throughout the country had an increase of 99%. In the studies of climate change in Mazandaran Province by Jahanbakhsh et al. (2010), based on the Mean annual variation in the 20-year time period (last two decades), showed that there is no significant difference in precipitation levels. Mohamadi (2010), also, analyzed the annual precipitation in Iran using data collected from 1437 synoptic, climatic and rainbow stations during the 40 years of 1964-2003. Results showed that in the time series of the station's Mean and precipitation, there observed no significant increase or decrease trend at 95% and 99% confidence levels .Farokhnia and Morid (2012) studied the trend of precipitation changes using four nonparametric tests of trend analysis in some of the stations in the basin of Urmia Lake and concluded that precipitation in this basin was largely lack of any trend. Khaliili et al. (2013) to declare the relationship between the monthly data trend and flow of SharChay River in western Uremia Lake, concluded that the decreasing trend of the flow in this river could be due to the increase of the climate variable and the dependence of the river discharge on the melting snow. Ababaei et al. (2014) investigated the Taleghan dam under the scenarios of climate change during 2040-2069. In this research, in order to demonstrate the ability of information combination methods with individual simulation methods, finally concluded that the Mean daily flow rate of the dam will decrease and the temperature of the basin will increase. The present study pointed out the uncertainty of many studies and significant contradictions resulting from the use of various models. 2. GENERAL LAYOUT 2.1 MATERIALS AND METHODS 629