A shift towards temperature-dominated droughts in agricultural basins of Türkiye

Droughts have become increasingly frequent and severe globally, posing substantial threats to water resources, agriculture, ecosystems, and communities. In this study, we explore the impact of climate change projections on drought occurrences in different agricultural regions of Türkiye which is characterized by diverse climatic zones reflecting those present within the Mediterranean basin. The analysis is performed using the Standardized Precipitation Index (SPI), the Standardized Precipitation-Evapotranspiration Index (SPEI) and the Aridity Index (AI). These indices, along with 16 climate model projections, were used to assess future drought characteristics until the end of the century and compare them to historical drought conditions. Our findings reveal that although precipitation does not have a clear trend in the coming decades, the frequency and severity of droughts are projected to intensify, particularly in the southern and central regions due to projected increase in temperatures. Statistical analyses of the SPI and SPEI indices indicate significant increase in projected number of drought and extreme drought events, with the SPEI demonstrating a more pronounced increase, underlining a shift from traditional precipitation deficit to temperature-dominated droughts in the region. Our analyses also reveal that climate projections are likely to induce changes in climate classification. The anticipated changes in drought drivers and characteristics emphasize the pressing need for effective drought monitoring strategies and adaptation measures to mitigate potential impacts on water resources and agricultural production in Türkiye and across the Mediterranean region.