Drought is considered to be one of the most devastating natural disasters. In recent years, determination of historical droughts has gained more importance. This can be attributed to the fact that once the trend of historical droughts is determined, it should be possible to struggle against drought more effectively. In this study, the drought analysis is performed in the Southeastern Anatolia Project (GAP) region, which is Turkey's biggest integrated project, using the monthly total precipitation data from 15 stations in nine provinces. Standardized precipitation index (SPI), being one of the most frequently used methods in the literature, is used to determine the drought indices. Temporal drought and occurrence of drought are calculated for 3, 6 and 12 month time scales. The non-parametric Mann–Kendall and Mann–Kendall Rank Correlation tests are used to determine the monotonic trends of drought indices and its year of initiation. The “Pre-whitened” method is used to remove serial correlation from time series before analysis. Linear slope of the trend is determined by Sen's Slope method, and Inverse Distance Weighting method is used for the spatial analysis. According to trends of temporal drought of the GAP region, a decreasing trend is found in 30% of the stations for 12-month SPI values with a statistical significance. Based on the results obtained from spatial analysis, there is a decreasing trend in most of the region for almost all time scales, and the slopes of trend are relatively higher in the north and south of the region.

干旱被认为是最具破坏性的自然灾害之一。近年来，确定历史干旱变得更加重要。这可以归因于这样一个事实，一旦确定了历史干旱的趋势，就可以更有效地抗旱。在这项研究中，干旱分析是在土耳其最大的综合项目东南安纳托利亚项目 (GAP) 地区进行的，使用来自 9 个省 15 个站点的月总降水量数据。标准化降水指数（SPI）是文献中最常用的方法之一，用于确定干旱指数。针对 3、6 和 12 个月的时间尺度计算了时间干旱和干旱的发生。非参数 Mann-Kendall 和 Mann-Kendall 秩相关检验用于确定干旱指数及其起始年份的单调趋势。“预白化”方法用于在分析前从时间序列中去除序列相关性。趋势的线性斜率由森的斜率法确定，空间分析采用反距离加权法。根据GAP地区的时间干旱趋势，12个月SPI值有30%的站点呈下降趋势，具有统计学意义。从空间分析的结果来看，几乎所有时间尺度上，大部分地区都存在下降趋势，并且该地区北部和南部的趋势斜率相对较高。