摘要:

The stability of an isolated one-layer reduced gravity front is examined. It is shown that the system is unstable to long-wave disturbances provided merely that a simple condition on the depth profile is satisfied far from the front. The instability does not require the extremum of potential vorticity needed by quasi-geostrophic theory. The instability releases mean kinetic and mean potential energy from the system, but lacking a second layer cannot truly be termed baroclinic instability.

ISSN:0309-1929    

DOI:10.1080/03091928308221751

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Nonlinear two-dimensional magnetoconvection, with a Boussinesq fluid driven across the field-lines, is taken as a model for giant-cell convection in the sun and late-type stars. A series of numerical experiments shows the sensitivity of the horizontal scale of convection to the applied field and to the Rayleigh numberR. Overstable oscillations occur in cells as broad as they are deep, but increasingRleads to steady motions of much greater wavelength. Purely geometrical effects can cause oscillation: this work implies that strong horizontal field will in general lead to time-dependent convection.

ISSN:0309-1929    

DOI:10.1080/03091928308221752

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The turbulent dynamo equation with non-uniform mean helicity is solved in an approximation, which is similar to the quasi-classical approximation of quantum mechanics. We evaluate the rate of growth of the magnetic field and obtain a condition for dynamo action. The generated magnetic field is concentrated in the vicinity of an extremum of mean helicity, but in general vanishes at the point of extremum itself. The field is asymptotically force-free. The results obtained here clarify the fact, known from numerical calculations, that the threshold values of the dynamo-number for excitation of dipole and quadrupole modes are very close to each other.

ISSN:0309-1929    

DOI:10.1080/03091928308221753

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

GEOSECS measurements of excess radon 222 as a function of depth above the sediments in the Atlantic and Pacific are sufficient to resolve the median profile in each ocean, but not the mean profile. The transport process maintaining the oceanic means is highly intermittent, and is not consistent with mixing by small scale turbulence generated at the ocean bottom. We suggest that transport of radon above the benthic boundary layer is driven by isopycnal motions associated with baroclinic instabilities on benthic fronts. A method for generating benthic fronts together with the subsequent instabilities is demonstrated in the laboratory.

ISSN:0309-1929    

DOI:10.1080/03091928308221754

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

edited by A. M. Soward, Gordon and Breach Science Publishers, 376 pp., 1983, Price $69.50. ISBN 0 667 16430 0 (Vol. 2 in “The Fluid Mechanics of Astrophysics and Geophysics” ISSN 0260 4353

ISSN:0309-1929    

DOI:10.1080/03091928308221755

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Edited by M. W. McElhinny, published by Academic Press 1979, 590 pp. Price: λ43.20; $95.50. ISBN: 0. 12. 482750. 0.

ISSN:0309-1929    

DOI:10.1080/03091928308221756

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Edited by L. Bengtsson and J. Lighthill, Springer-Verlag, Berlin, 1982, 326 pages. Price: US $23.40. DM 56,-; approx. ISBN 3 540 11657 5

ISSN:0309-1929    

DOI:10.1080/03091928308221757

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

by H. S. Goldberg and M. D. Scadron, Gordon and Breach, 1981. xiv + 390 pp. Price: $59.50. ISBN 0677055404

ISSN:0309-1929    

DOI:10.1080/03091928308221758

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0309-1929    

DOI:10.1080/03091928308221759

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor