摘要:

Analysis of a two-layer, flat-bottom, steady-wind driven, eddy-resolving general circulation model reveals a distinct separation in frequency of baroclinic and barotropic motion in the region distant from the model Gulf Stream. The far-field motions at periods less (greater) than about 100 days are predominantly barotropic (baroclinic), unlike the near-field, eddy-generating, free-jet region which contains barotropic and baroclinic energy throughout the modei frequency range. The far-field barotropic energy produces a peak in the model sea-level spectra between 25 and 50 days with a magnitude comparable to energy levels observed in spectra of sea level from oceanic island tide gauges. The far-field barotropic motion is clearly composed of large-scale, resonant, barotropic normal modes drive by mesoscale activity of the turbulent, free-jet region. Oceanic mesoscale turbulence may therefore provide for planetary normal modes an excitation mechanism distinct from atmospheric forcing. The open-ocean, barotropic, model response is very similar to that of a fluctuating-wind driven model, which suggests that atmospheric and intrinsic forcing of mid-ocean eddies may be of comparable importance.

ISSN:0309-1929    

DOI:10.1080/03091928708210099

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Simple analytical solutions are presented for topographic waves in elliptical basins whose isobaths form a set of confocal ellipses. It is shown that the previous solution presented for this problem is incomplete. The complete solutions no longer agree so closely with observations in Swiss lakes and the Great Lakes. The class of profiles considered is extended to include flat-bottomed basins, allowing a more realistic estimate of the velocity distribution in such basins and suggesting a slightly closer agreement of predicted period with observations.

ISSN:0309-1929    

DOI:10.1080/03091928708210100

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Magnetic buoyancy instabilities may be a significant cause of flux loss from the solar interior. This paper extends the linear theory for such instabilities, which has been widely studied, into the weakly non-linear régime to obtain solutions valid for small but finite-amplitude motions. We consider both static and rotating equilibrium states but, for simplicity, focus attention only on the two-dimensional interchange modes. The method used in obtaining the solutions is due to Coullet and Spiegel (1983)—a summary of the method, together with its advantages, is contained in Section 2.

ISSN:0309-1929    

DOI:10.1080/03091928708210101

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor