Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 1.490 IF 1.490
  • IF 5-year value: 1.445 IF 5-year
    1.445
  • CiteScore value: 2.9 CiteScore
    2.9
  • SNIP value: 0.789 SNIP 0.789
  • IPP value: 1.48 IPP 1.48
  • SJR value: 0.74 SJR 0.74
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 88 Scimago H
    index 88
  • h5-index value: 21 h5-index 21
Volume 29, issue 8
Ann. Geophys., 29, 1377–1381, 2011
https://doi.org/10.5194/angeo-29-1377-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
Ann. Geophys., 29, 1377–1381, 2011
https://doi.org/10.5194/angeo-29-1377-2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.

ANGEO Communicates 19 Aug 2011

ANGEO Communicates | 19 Aug 2011

On the unstable mode merging of gravity-inertial waves with Rossby waves

J. F. McKenzie J. F. McKenzie
  • Department of Mathematics, Statistics and Physics, Durban University of Technology, Durban, South Africa
  • School of Mathematical Sciences, University of KwaZulu-Natal, Durban, South Africa
  • CSPAR, University of Alabama, Huntsville, USA

Abstract. We recapitulate the results of the combined theory of gravity-inertial-Rossby waves in a rotating, stratified atmosphere. The system is shown to exhibit a "local" (JWKB) instability whenever the phase speed of the low-frequency-long wavelength westward propagating Rossby wave exceeds the phase speed ("Kelvin" speed) of the high frequency-short wavelength gravity-inertial wave. This condition ensures that mode merging, leading to instability, takes place in some intermediate band of frequencies and wave numbers. The contention that such an instability is "spurious" is not convincing. The energy source of the instability resides in the background enthalpy which can be released by the action of the gravitational buoyancy force, through the combined wave modes.

Publications Copernicus
Download
Citation