The change of the Earth Pole oscillational mode under the Lunar-Solar perturbations

Abstract

This article investigates conversion between different modes of the Earth Pole oscillational process which influence the precision of the Pole position forecast. It identifies the perturbing harmonic that leads to the saltatory change of the average velocity of Earth Pole motion and to the change of its oscillational mode. It also shows the qualitative conformity between the four-frequency model of the Pole motion and observation data based on the graph of phase variation of the polar angle of the Pole rotation around the average position.