Canonical treatment of dissipative forces between Earth mantle and core

Abstract

Abstract. Dissipative effects arising from the core-mantle interaction are treated in a Hamiltonian framework, using a simple model. Analytical solutions are obtained for free and forced motions. The first show the persistence or damping of the different components. The latter, frequency dependent changes of amplitude and phase. Preliminary numerical values axe in acceptable agreement with observational data.

Geophysical excitation of the Earth orientation parameters EOP and its contribution to GGOS

“…There are two important resonances that are considered in the Earth nutation: the resonance at the free core nutation (FCN) and the resonance at the free inner core nutation (FICN). Two other resonances at frequencies outside the nutation frequency band are also relevant for nutation: the resonance to the Chandler Wobble (CW) and to the Inner Core Wobble (ICW) (see Dehant and Defraigne, 1997;Mathews et al, 2002;Buffett et al, 2002;Getino and Ferrándiz, 1996). At the level of precision reached by the very long baseline interferometry (VLBI), i.e.…”