Spatiotemporal Changes of Drought Conditions Over the Hindu‐Kush Himalayan Region During the Recent Century: Insights for Climate Adaptation

ABSTRACT The Hindu Kush Himalayan (HKH) region, a critical water source for 2 billion people, exhibits contrasting drought patterns under climate change. Using the Self‐Calibrating Palmer Drought Severity Index (scPDSI) and spatiotemporal analyses (1901–2022), we reveal a regional dichotomy: significant drought reduction in Afghanistan, China, and Pakistan (scPDSI slope ≤ +0.016/year, p < 0.05) versus intensifying aridity in Bangladesh, Bhutan, Myanmar, and Nepal (slopes ≥ − 0.015/year, p < 0.05), with India stable (slope = −0.002/year, p > 0.05). Precipitation dominates drought recovery in western HKH (e.g., Pakistan and Afghanistan: r = 0.77), whilst Arctic Oscillation (AO) teleconnections amplify resilience in China ( β = 0.43, p < 0.05). Eastern regions face temperature‐mediated drought intensification (Bangladesh: r = −0.33) and divergent ENSO impacts (Myanmar: r = −0.32). Spatial clustering (Moran's I = 0.753, p < 0.001) confirms drought trends are non‐random, driven by climatic drivers. Mechanistic contrasts emerge: western HKH recovery links to precipitation and snowmelt, whilst eastern regimes integrate AO and Australian Summer Monsoon synergies. Drought relief areas doubled (1.15–2.34 million km 2 , 1901–2022), accelerating post‐1960, contrasting with lowland drought expansion (e.g., Indus Basin). These findings demand spatially targeted adaptation: water‐efficient agriculture in precipitation‐sensitive lowlands and climate‐resilient storage in high‐elevation zones. By bridging hydroclimatic trends with hybrid modelling of threshold‐driven drivers, this study advances transboundary governance frameworks to mitigate the HKH's water insecurity.