ECS (Extremely compact sources) potential field filtering. The case of Greenland and Antarctica ice mass balance (2002-2017).

We introduce a novel estimation technique to assess the overall mass variations of the Greenland and Antarctica ice sheets. Interpreting GRACE data encounters a significant challenge due to the leakage effect resulting from the presence of outlying melting ice bodies, causing gravitational effects to interfere with each other. Our estimation employs an innovative approach that leverages the non-uniqueness of the gravity field, using a hypercompact model of the sources through an iterative inversion. Furthermore, thanks to to the extreme compactness of the sources, our method enables a more unambiguous quantification of total mass loss in the study area. We apply our method to time-varying NASA GRACE (Gravity Recovery and Climate Experiment) Stoke's coefficient data spanning from 2002 to 2017. Over a 15-year period, the GRACE and subsequent GRACE-FO missions provided a distinctive to map the Earth's gravitational field time variations. In recent years, recognizing the ice sheet's total mass response to climate change has become pivotal in comprehending phenomena such as sea level rise associated with grounded ice melting and quantifying the retreat of ice sheet fronts in polar regions, offering the scientific community a fresh perspective on unknown ice sheet dynamics.