Dynamic Analysis of the Perturbed Motion of the Earth’s Pole

Within the framework of the spatial variant of the “deformable Earth-Moon” problem in the solar gravitational field for the viscoelastic Earth model, tidal deformations caused by long-period lunar disturbances are determined. The dynamics of the Earth’s pole motion with Chandler and annual frequencies is analyzed taking into account the obtained expressions for the centrifugal moments of inertia of the Earth. Using numerical integration of the equations of pole motion, it is shown that the found structure of variations in the centrifugal moments of inertia leads to oscillations in the amplitudes of the Chandler and annual harmonics with an 18-year period of precession of the Moon’s orbit.