Related papers: Formulation of a Triaxial Three-Layered Earth Rota…
We compute the inertial modes of a freely rotating two-layer planetary model with an ellipsoidal inviscid fluid core and a perfectly rigid mantle. We present a method to derive analytical formulae for the frequencies of the Free Core…
Periodic variations in the Sun and Moon's gravitational pull cause small changes in Earth's rotational axis direction called nutation. Nutation components in the retrograde quasi-diurnal frequency band measured in the terrestrial reference…
The Earth is a rapidly rotating body. The centrifugal pull makes its shape resemble a flattened ellipsoid and Coriolis forces support waves in its fluid core, known as inertial waves. These waves can lead to global oscillations, or modes,…
The geodynamic state of the inner core remains an enigma, encompassing the presence of a static tilt between the inner core and mantle. Following the experimental confirmation of an ~8.5yr signal in polar motion as the inner core wobble…
The time-varying response of the Earth's and other planets' rotation to external gravitational torques depends strongly on their internal structure. In particular, the existence of the mode known as the Free Core Nutation in the fluid core,…
We report a calculation of time-dependent quasi-geostrophic core flows for 1940-2010. Inverting recursively for an ensemble of solutions, we evaluate the main source of uncertainties, namely the model errors arising from interactions…
Free core nutation (FCN) is the main factor that limits the accuracy of the modeling of the motion of Earth's rotational axis in the celestial coordinate system. Several FCN models have been proposed. A comparative analysis is made of the…
The Chandler wobble (CW) -- the $\sim$433-day free nutation of Earth's rotation pole -- experienced an anomalous near-disappearance between 2015 and 2020, followed by a re-excitation with an approximately $180^{\circ}$ phase reversal. Using…
In this study, three empirical Free Core Nutation (FCN) models developed to the present time, MHB2000, Malkin's and Lambert's ones, are compared on the basis of representation of variations of the FCN amplitude and phase predicted by these…
The inner structure of the earth is still a topic of discussion. Seismic measurements showed a structure of solid, liquid, solid which describes the mantle, outer core and inner core with the inner core in the center. The analysis of…
Investigations of the anomalies in the Earth rotation, in particular, the polar motion components, play an important role in our understanding of the processes that drive changes in the Earth's surface, interior, atmosphere, and ocean. This…
The mantle-inner core gravitational (MICG) mode is the free mode axial oscillation between the mantle and inner core sustained by the gravitational torque between their degree 2 order 2 density structures. Here, we investigate how the MICG…
The diurnal tidal forces can excite a normal mode of the Earth's core, the free inner core nutation (FICN), which is characterized by a tilt of the rotation axis of the inner core with respect to the rotation axis of the outer core. The…
A magneto-hydrodynamic model of boundary layers at the Core-Mantle Boundary (CMB) is derived and used to compute the viscous and electromagnetic torques generated by the Earth's nutation forcing. The predicted electromagnetic torque alone…
In this paper, in the first instance the attitude dynamics of the Earth is modelled based on physical principles so as to correctly predict the Chandler wobble and its features such as its period. To this end not only the steady state and…
We investigate the pressure torque between the fluid core and the solid mantle arising from magnetohydrodynamic modes in a rapidly rotating planetary core. A two-dimensional reduced model of the core fluid dynamics is developed to account…
Thermal convection in rotating stars and planets drives anisotropic turbulence and differential rotation, both capable of feeding energy into global oscillations. Using 3D simulations of rotating convection in spherical shells, we show that…
Rotation of triaxially deformed nucleus has been an interesting subject in the study of nuclear structure. In the present series of work, we investigate wobbling motion and chiral rotation by employing the microscopic framework of…
After describing all the contradictions associated with the current Plate Tectonics theory, this paper proposes a model where a single cause can explain all geophysical and geological phenomena. The source of the Earth's activity lies in…
A particle-triaxial rigid core Hamiltonian is semi-classically treated. The coupling term corresponds to a particle rigidly coupled to the triaxial core, along a direction that does not belong to any principal plane of the inertia…