Time variations of geopotential coefficients in the structure of the oscillatory process of the Earth's pole

摘要

A numerical-analytical model of the oscillatory motion of the Earth's pole is proposed with allowance for effects of time variations in geopotential coefficients. The model is a natural refinement of the earlier developed main model of pole oscillations (of Chandler and annual components) by use of celestial mechanics methods and observation data of the gravitational field of the Earth. Based on amplitude-frequency analysis and numerical simulation of the pole motion, the model allows one to offer a qualitative explanation of observed irregular phenomena in the oscillatory process and improve the forecasting accuracy for the trajectory of the pole motion. The results of numerical simulation of oscillations of the pole coordinates are presented in comparison with observation and measurement data of the International Earth Rotation Service (IERS).