Study on the Earth’s Mass Balance and Shape from Satellite Gravimetry

- Hydrological Application and Gravimetric Geoid Modeling -

Abstract

　The dedicated satellite gravimetry missions that emerged at the beginning of the 21st century have paved fresh avenues for studying geodesy and geophysics. The Gravity Recovery and Climate Experiment (GRACE) has enabled precise measurement of the time-variable gravity field of the Earth, providing new insights into large-scale mass redistribution in the Earth system. The Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) has enabled precise determination of the physical shape of the Earth, realizing the implementation of a global unified height reference system based on geoid. This article reviews the authorʼs studies on the Earthʼs mass balance and shape using the data from the satellite gravity missions. The following two topics are reviewed here: (1) analysis of precipitation anomaly signature associated with Arctic Oscillation using GRACE data, (2) improvement of a gravimetric geoid model for Japan using GOCE data. At the end of this article, the current status and future plans of satellite gravimetry missions are reviewed.