Climatic zoning of Türkiye under drought stress: a cluster analysis approach

Abstract

Understanding drought variability across regions is vital for sustainable water management and climate adaptation in Türkiye. Traditional climatic classifications were not designed with a drought-oriented focus, limiting their ability to represent multi-scale drought behaviour. This study addresses this gap by combining the Standardized Precipitation Index (SPI) and the Standardized Precipitation Evapotranspiration Index (SPEI), calculated at 1-, 3-, 6-, 9-, and 12-month accumulation periods, with Ward’s hierarchical clustering and a comparison of recurrent clustering patterns across indices and time scales. Long-term records from 78 meteorological stations covering 1950–2023 were analysed to delineate homogeneous drought regions. The analysis identified seven drought-oriented zones; Central and Southeastern Anatolia showed the most recurrent station groupings and strongest spatial coherence across the examined scales. This integrated application of established methods provides a drought-focused basis for regional risk assessment, water policy, and climate adaptation planning in Türkiye.