EVIDENCE OF NONLINEARITY OF THE CHANDLER WOBBLE IN THE EARTH'S POLE MOTION

Abstract

It is well known that rotational motions with annual and Chandler periods dominate in the dynamics of the location of the Earth’s poles. The nature of the Chandler wobble is not clear. It is most frequently attributed to elasticity and differential rotation of different internal spheres of the Earth. Recently, it was shown that the Chandler-type motions are possible in a model of solid Earth if this model is nonlinear with an annual external influence (the deviation of the equatorial section of the Earth’s shape from the pure circular form is taken into account).