On ?pathological oscillations? of rotating fluids in the theory of nutation

Molodensky, S. M.; Groten, E.

doi:10.1007/bf00868223

Cited by 5 publications

(3 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An exposition of the two above-described approaches is given in the papers cited above, and we will not consider them in detail. Instead, we will dwell on the technique of solving the problem based on the representation of oscillations in the rotating inhomogeneous, gravitating fluid as a superposition of solutions to the generalized Laplace tidal equations, which describe the oscillations of a thin spherical fluid shell with movable boundaries Sasao, 1995a, 1995b;Molodensky and Groten, 1996, 1998a, 1998b.…”

Section: Solutions To the Tidal Dynamical Equations For A Compositionmentioning

confidence: 99%

“…Some general properties of these matrices were considered by Molodensky and Groten (1996). It was shown that (i) these matrices are quasi-diagonal (their elements differ from zero if i = k, i = k -2, or i = k + 2); (ii) the matrices a ik are symmetric: a ik = a ki ; and (iii) due to the Laplacian resonance at κ = 0 (see, e.g., Lamb, 1932), the matrix elements a ik and b ik for i = k = 2 and at κ 0 increase indefinitely, while all other nonvanishing matrix elements approach finite limits.…”

Section: Molodenskymentioning

confidence: 99%

See 1 more Smart Citation

Tides and nutation of the Earth: II. Realistic models of the liquid core

Molodensky

2005

Sol Syst Res

Self Cite

View full text Add to dashboard Cite

In the first part of this study (Molodensky, 2004; hereinafter, paper I), a survey of the theory of tides and nutation of the Earth was given with the inclusion of the dynamical effects of the elastic mantle and liquid core in the framework of a very simple model of a homogeneous, incompressible core. Here, effects of the inhomogeneity, compressibility, and viscosity of the liquid core are considered, along with those of electromagnetic coupling of the liquid core with the mantle and solid inner core. Errors in the present-day measurements of the amplitudes of forced nutation (of the order of 20 arc µ s) are well below not only the dynamical effects of the Earth's liquid core but also the effects of the inelasticity of the mantle, the dynamical effects of the solid inner core, and the possible effects of electromagnetic coupling between the liquid core, solid inner core, and mantle. This opens up new avenues for astrometric studies of the mechanical properties and electrical conductivity of the mantle and solid inner core at very low frequencies. The modern data on the amplitudes and phases of the Earth's forced nutation cannot be interpreted entirely unambiguously, since the following factors remain unknown: (i) the role of the core-mantle electromagnetic coupling compared to the coupling due to core viscosity near the core-mantle boundary and (ii) the frequency dependence of the creep function of the mantle at low frequencies. In large measure, the effects of electromagnetic and viscous coupling can be separated if highprecision data on the tidal variations in the gravitational force at periods of about a day are invoked and allowances are made for the differences between the effects of viscous and electromagnetic coupling on the amplitudes and phases of forced nutation and on the tidal variations in the gravitational force. Here, ranges of possible values of the creep function are constructed for periods from one hour to one day; for these calculations, values consistent with the entire set of data on the forced nutation of the Earth are assumed for the effective dynamical flattening of the liquid core-mantle and liquid core-solid inner core boundaries (these values describe the ellipticity of the boundaries of the inner core, outer core, and mantle, as well as the electromagnetic coupling between the liquid core, mantle, and solid inner core).

show abstract

Section: Solutions To the Tidal Dynamical Equations For A Compositionmentioning

confidence: 99%

Section: Molodenskymentioning

confidence: 99%

Tides and nutation of the Earth: II. Realistic models of the liquid core

Molodensky

2005

Sol Syst Res

Self Cite

View full text Add to dashboard Cite

show abstract

“…Eqs (9a) and (12) do not contain any small parameters; at the same time, they also belong to the class of ill‐posed (in the sense of Hadamard) boundary problems [because they are of hyperbolic type with one boundary condition (13) on the closed surface s; for a discussion see Melchior (1986, pp. 102–109); Molodensky & Groten (1996) ]. Taking these circumstances into account, one realizes that an exact integration of this equation has many difficulties associated with it.…”

Section: Relations Between General 3‐d Hydrodynamical Equations Andmentioning

confidence: 99%

On the dynamical effects of a heterogeneous and compressible liquid core in the theory of Chandler wobble

Molodensky¹,

Groten²

1998

Geophysical Journal International

Self Cite

View full text Add to dashboard Cite

The general 3‐D scalar equations of motion of the liquid core (with respect to the radial components of displacements and cubic dilatation) are constructed as a superposition of the solutions of ordinary differential equations describing the dynamics of a stably stratified, heterogeneous, compressible and inviscid rotating fluid inside thin spherical layers (Molodensky & Sasao 1995). The estimation of dynamical effects of a homogeneous and incompressible liquid core on the Chandler period (Groten, Lenhardt & Molodensky 1991) is generalized for the case of a heterogeneous, compressible, inviscid and neutrally stratified liquid core.

show abstract

On Some Physical Aspects of the Earth’s Rotation

Molodensky

1999

Acta Geod. Geoph. Hung

View full text Add to dashboard Cite

On ?pathological oscillations? of rotating fluids in the theory of nutation

Cited by 5 publications

References 16 publications

Tides and nutation of the Earth: II. Realistic models of the liquid core

Tides and nutation of the Earth: II. Realistic models of the liquid core

On the dynamical effects of a heterogeneous and compressible liquid core in the theory of Chandler wobble

On Some Physical Aspects of the Earth’s Rotation

Contact Info

Product

Resources

About