Impacts of Population Dynamics and Climate Extremes on Water Resource Security in Central Asia

ABSTRACT: Central Asia (CA), as a representative arid region globally, faces severe water scarcity, which has posed significant threats to its sustainable development over the past decades. A systematic understanding of the dynamic changes in surface water area (SWA) and terrestrial water storage (TWS) is crucial for ensuring human survival and maintaining the regional ecosystem balance. While previous studies have documented water resource depletion in Central Asia, they often lacked comprehensive analyses of the primary drivers of surface water area decline. To address this gap, we analyzed interannual variability and trends in SWA and TWS across Central Asia from 1990 to 2023. This analysis used Landsat-5/7/8/9 surface reflectance data, Gravity Recovery and Climate Experiment (GRACE) mascon data, an improved robust water mapping algorithm, and the Google Earth Engine (GEE) cloud computing platform. Results indicate a continuous and substantial decline in SWA across the CA, primarily driven by irrigation withdrawals and surface water evaporation. Additionally, population growth and extreme climate change have posed a new potential threat to regional water security. This study highlights the critical importance of ecological water resource management in promoting the coordinated development of regional food, water, and ecological security, thereby supporting long-term sustainable development.

Key words： Surface water body；Terrestrial water storage；Landsat；Google Earth Engine