Investigation drought conditions and soil moisture of Southeastern Anatolia Project (GAP) region (Türkiye)

Investigation drought conditions and soil moisture of Southeastern Anatolia Project (GAP) region (Türkiye) | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Investigation drought conditions and soil moisture of Southeastern Anatolia Project (GAP) region (Türkiye) zeyneb kılıç This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7692715/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study investigates drought and soil moisture dynamics between 1963 and 2022 in seven provinces of Southeastern Anatolia (Adıyaman, Diyarbakır, Gaziantep, Kilis, Mardin, Siirt, Şanlıurfa), using four drought indexes (SPI, SPEI, CZI, RDI) at 1-, 3-, and 12-month time scales; allows for a comprehensive assessment, which is not commonly done before in studied provinces. ERA5-Land soil moisture data (1950-2022) were also analyzed to provide additional insight. The results reveal Diyarbakır and Şanlıurfa as the most drought-prone provinces, exhibiting the lowest median index values and highest frequency of extreme droughts. SPEI-12 (THW) median values ranged from -0.0714 (Adıyaman) to 0.188 (Şanlıurfa), suggesting a near-neutral long-term balance with strong seasonal variability. Soil moisture levels declined sharply in summer months, reaching as low as 2-3 mm, particularly after 2009, indicating increased evapotranspiration stress. RDI-12 showed strong correlations (0.87-0.97) with other indexes, proving its reliability in capturing long-term drought patterns. Spatial analysis showed that while mild drought frequency reached up to 39% in the southwest, severe and extreme droughts were more frequent (up to 8%) in the east. Conversely, wet events were more dominant in eastern areas such as Siirt, with frequencies exceeding 53%. These findings emphasize the necessity of multi-index drought monitoring and the importance of soil moisture data in supporting water management, agricultural planning, and climate adaptation in semi-arid regions. Meteorology Drought analysis spatial analyses ArcGIS soil moisture GAP Türkiye Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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