THE TIDAL MOTIONS OF A ROTATING , ELLIPTICAL, ELASTIC AND OCEANLESS EARTH

A theoretical study is presented of the response of a rotating, elliptical and elastic Earth to the combined gravitationalattraction of the Sun and Moon. Five of the most heavily constrained contemporary models of the Earth's material structure are considered (all have a fluid outer core and a solid inner core). The non-orbital part of the response is separated into the body tide (the Earth's deformation), the precession and nutation of the Earth, and changes in the Earth' s rotation rate. In particular, the nutations are shown to be the best represented by motion of the 'Tisserand mean figure axis of the surface', which also is essentially a mean mantle fixed axis