Quantifying long-term water storage in Ebinur Lake through integration of multi-source satellite data and hydrological observations

Quantitative monitoring of lake water storage in arid regions is essential for effective management of regional water resources, and can also elucidate the impacts of ecological degradation on lake water storage. This study investigates changes in water storage in Ebinur Lake, Xinjiang, from 2011 to 2024 using field–measured water depth data and multi–sensor satellite remote sensing data, including optical (Landsat-5/7/8, Sentinel-2, and MODIS) and LiDAR (ICESat-2) data. After preprocessing the satellite images acquired on different dates, including radiometric and atmospheric correction, maps of lake area and reconstructed water depth patterns were generated, and water storage was calculated. Finally, the driving factors influencing changes in water storage over time are examined. The results indicate that Ebinur Lake underwent three distinct phases: “expansion (2011–2017), shrinkage (2018–2023), and brief recovery (2024)”. Interannual and warm-season monthly variations were notably pronounced, with the coefficient of variation fluctuating between 4.10% and 52.10%. The lake area reached a maximum of 865.99 km² and a minimum of 58.23 km². The reconstructed water depth pattern of the lake is relatively homogeneous and predominantly shallow, with the central area being deeper and the edges being shallower. Overall, the lake exhibits a shallow-basin morphology during the study period. The water storage ranges from 1.26 × 10⁸ m³ to 10.49 × 10⁸ m³, showing an annual average decline of 2.31%. The water storage of Ebinur Lake is influenced by factors such as river inflow, atmospheric precipitation, ambient temperature, evapotranspiration, and human activities, with river inflow being the key driving factor behind the variation in water storage.