Spatiotemporal dynamics of drought and wet extremes across Gujarat's agro-climatic zones: Insights from multi-index analysis and return period modelling

Hydroclimatic extremes are becoming increasingly important under a changing climate because of their impacts on water resources, agriculture, and regional sustainability. Gujarat, Western India, experiences substantial monsoon variability and is highly vulnerable to both droughts and extreme wet events. This study assessed hydroclimatic variability across eight agro-climatic regions of Gujarat during 1980–2024 using precipitation- and evapotranspiration-based drought indicators, drought characterization, return period estimation, correlation analysis, and climatic teleconnections assessment. The analysis identified 1987, 2002 and 2015 as major drought years across most regions, while 1994, 2013 and 2020 were characterized by widespread wet conditions. Strong agreement among the drought indicators confirmed the robustness of hydroclimatic assessments, whereas the temperature-sensitive indicator consistently captured longer drought durations, highlighting the increasing role of atmospheric warming in drought persistence. Regional differences were pronounced, with Kachchh and South-Saurashtra emerging as the most drought-prone regions, while North Gujarat exhibited a higher recurrence of moderate drought conditions. Return period analysis indicated that severe droughts are relatively infrequent but potentially high-impact events, whereas recurrent moderate droughts impose persistent stress on agriculture, groundwater resources, and rural livelihoods. Hydroclimatic variability was strongly influenced by large-scale ocean–atmosphere circulation systems. Variations in the El Niño-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) were closely associated with alternating drought and wet phases through their influence on the Indian Summer Monsoon. The impacts of these extremes varied considerably among agro-climatic regions, with arid regions facing greater risks of water scarcity and reduced crop productivity. However, humid and coastal regions were more vulnerable to flooding, waterlogging, and crop damage. These findings provide a regional framework for climate-risk assessment and support climate-resilient water-resource management, agricultural planning, early-warning systems, and adaptation policies, thereby contributing to Sustainable Development Goals (SDGs) 13(Climate Action).