The Time Evolution of the Earth's Gravity Field Since 2002: Do we need to rethink geopotential-based reference systems in the GRACE era?

Abstract:

The gravity field of the Earth has changed dramatically over the last few decades as it responds to the melting of continental ice, depletion of groundwater, glacial isostatic adjustment, earthquakes, and other effects. The GRACE mission, launched in 2002, allows us to quantify these effects on gravity anomalies, geoid heights, deflections, and geopotential-based vertical reference systems at long wavelengths. We will examine these changes in different parts of the world and discuss the potential implications for different applications employing static (mean) gravity field models. We will furthermore show that GRACE and future satellite gravity missions can inform the changes in these vertical datums as the Earth's gravity field continues to evolve.