Monthly and Annual Trend Analysis of Precipitation Over Southeastern Anatolia Project (Gap) Cities in Turkey
Precipitation is one of the most important climate parameters that effects people directly. Changes in precipitation
influence on many activities such as economy, tourism and agriculture closely. Euphrates and Tigris Basins are main water
resources for East Anatolia and Southeastern Anatolia regions. These two basins are composed of over than 25% of total
average water potential in Turkey. They are also important for irrigation and agriculture in Southeastern Anatolia region.
Thus, it is important to present the change of precipitation in that region in order to detect drought and sustain agricultural
activities. In this study, monthly total precipitation data from 9 cities which are located around Southeastern Anatolia Project
are used. Data periods were consisting of between 1965 and 2013. Mann-Kendall trend test has been applied to that data for
0.05 and 0.10 significance levels. Especially in Mardin station, decreasing trend was observed for 0.05 significance level in
total precipitation values in March and April. Annual precipitation values of Mardin station also indicated decreasing trend
in 0.05 significance level. Besides, decreasing trend was observed in Şırnak station for November. In addition, decreasing
trend was observed in Kilis station for March and for annual precipitation with 0.05 and 0.10 significance levels,
Keywords - Trend Analysis, Mann-Kendall, Southeastern Anatolia Project, precipitation.