Trend analysis of precipitation play a significant role in the efficient water resources management, especially in arid and semi-arid regions. In this study, 48 years-long (1970-2017) annual precipitation data monitored at nine selected stations (Mardin, Adıyaman, Batman, Diyarbakır, Siirt, Şırnak, Gaziantep, Kilis and Şanlıurfa) in the Southeastern Anatolia Region, Turkey were investigated by using the Innovative Şen Metod (ISM) and Mann-Kendall trend test (MK). The ISM has nonparametric basis without any restrictive assumption, moreover, its application is rather simple when compared with the other trend identification methods. Since the significance test is a crucial factor to identify the possible trends scientifically, the results were statistical tested at the 5% significance level in MK and in accordance with the proposed approach presented by Şen. The result revealed that the trend of annual precipitation was decreasing only in Mardin (Z = -2.12) with respect to both MK test. This result also approved by the ISM. Considering the other eight provinces, the ISM describe no trend at Batman, Diyarbakır and Kilis, increasing trend at Gaziantep, Adıyaman and Şırnak, and decreasing trend at Siirt and Şanlıurfa. It is concluded that the innovative method (ISM) has potential to present the monotonic and non-monotonic trends in graphical format, and a valuable method that avoids the assumptions such as independent structure of the time series, type of probability distribution function and length of the data.  

Keywords - Innovative trend analysis, Mann-Kendall test, Precipitation, Southeastern Anatolia Region, Turkey

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