A Numerical Experiment to Test the Influence of the Uncertainty of Earth Model on Nutation

Monday, 15 December 2014
Cheng-Li Huang and Mian Zhang, Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai, China
From an infinite set of coupled ordinary differential equations that govern the infinitesimal elastic-gravitational oscillations of a rotating, slightly elliptical Earth, as well as a set of boundary conditions on displacement vector, stress tensor and gravity potential, the theoretical nutation model of non-rigid earth can be numerically obtained. In these differential equations and the boundary conditions, the distributions of density and elastic (Lame) parameters interior the Earth are key parameters and are usually input from 1D earth model like PREM. However, the influence of the uncertainty of a given earth model on nutation has never been checked. In this work, we made a numerical experiment to test it, and some primary results will be presented.