A combination of Time-Variable Gravity Field Solutions from Multi-Satellite Datasets (1993-2024) via Constrained Collocation Model

This study develops monthly gapless, filter-free gravity field solutions from January 1993 to December 2024, which merge multiple satellite observations without hydrometeorological models, achieving better accuracy than current methods. Assessment of sea level budget closures and water balance at global and basin scales shows major gains. Ice sheet mass changes in Antarctic and Greenland show higher consistency with reference estimates, enabling reliable tracking of global water and ice systems.