Gravitational potential, inertia and Earth rotation

TL;DR

This paper explores how satellite-derived Earth's gravitational potential and geopotential coefficient variations relate to Earth's rotation parameters, aiming to enhance understanding of Earth's rotational dynamics through gravitational data.

Contribution

It establishes a link between Earth's gravitational potential variations and rotation parameters, proposing the use of Stokes coefficients to improve Earth's rotation knowledge.

Findings

Earth gravity field variations relate to Earth's rotation parameters.

Stokes coefficients can potentially improve Earth's rotation models.

Satellite data enhances understanding of Earth's inertia and rotation.

Abstract

Several satellite missions, devoted to the study of the Earth gravity field, have been launched (like CHAMP, recently). This year, GRACE (Gravity Recovery and Climate Experiment) will allow us to obtain a more precise geoid. But the most important is that they will supply the temporal variations of the geopotential coefficients (called Stokes coefficients). In the poster we show how the Earth gravitational potential is linked to the Earth rotation parameters. Indeed, through the Earth inertia coefficients, we can connect the variation of LOD and Polar Motion with the temporal variations of the Stokes coefficients. We also consider the nutations, that are related to the gravitational geopotential coefficients. We discuss the possibility of using the Stokes coefficients in order to improve our knowledge of the Earth rotation.