Global daily mascon solutions at 330 kilometers from line-of-sight gravity differences for rapid variation analysis

Abstract The Gravity Recovery and Climate Experiment and its Follow-On mission have revolutionized the monitoring of terrestrial water storage dynamics since 2002, offering monthly global mass transport data at ~300 kilometers resolution. Nevertheless, their temporal resolution remains insufficient to resolve rapid mass fluctuations triggered by extreme hydrometeorological events. Existing methods cannot achieve reliable high spatiotemporal resolution in the absence of external data. Here, we propose a spatiotemporally regularized framework to recover global daily mascon solutions from line-of-sight gravity differences, independent of a priori information, at an effective spatial resolution of ~334 kilometers. Our daily results accurately capture extreme flood signals in South Asia (July 2019), Australian (March 2021) and flood storage process at the Three Gorges Dam (July 2020), highlighting its role in attenuating peak flows. This advancement establishes a paradigm for model-independent, high-cadence mass change monitoring and analysis, with applications in extreme event attribution and model validation.