Basal melting of Antarctic ice shelves from 2012 to 2023 derived from CryoSat-2

Basal melting of Antarctic ice shelves is a key process driving ice-shelf thinning and dynamic mass loss of the ice sheet. Based on CryoSat-2 SARIn radar altimetry data from 2012 to 2023, this study derives a dataset of surface elevation, elevation change rates, thickness, and basal melt rates for 49 major Antarctic ice shelves within a Lagrangian framework. The results show that the mean basal melt rate of Antarctic ice shelves is 0.52 ± 0.72 m yr−1, with pronounced spatial heterogeneity. Melting is concentrated in the Amundsen and Bellingshausen Sea sectors of West Antarctica, with the Amundsen Sea ice shelves exhibiting the most pronounced melt rates (5.73 ± 0.92 m yr−1). Ice-shelf thickness changes exhibit a strong spatial coupling with basal melting, with regions of rapid thinning closely coinciding with areas of intense melt and predominantly concentrated near the grounding line. In addition, ice-shelf thinning and basal melting display pronounced interannual variability, with strong melt events occurring during 2014–2016 and 2019–2021. This study employs a Lagrangian framework to effectively suppress advection-induced noise, thereby enhancing the reliability of Antarctic ice-shelf change retrievals. The resulting nearly 12-year continuous, high-resolution dataset provides a robust foundation for investigating ice shelf-ocean interactions and assessing the stability of the Antarctic Ice Sheet.