Goswami, BN and Goswami, P (1994) Mechanisms of some tropical intraseasonal oscillations. In: Geophysical Research Letters, 19 (7). pp. 681-684.Full text not available from this repository.
An underlying mechanism for two westward propagating tropical intraseasonal oscillations is discovered. Destabilization of equatorial normal modes by moist feedbacks, in particular, by evaporation-wind feedback, is responsible for both of them. The westward propagating 4-5 day oscillation and the quasi-biweekly oscillation result from destabilization of the mixed Rossby gravity (MRG) wave by the evaporation-wind feedback. The frequency and scale-selection of the unstable MRG wave depend critically on the background mean wind. In mean easterlies (as in the Pacific and the Atlantic), it results in the 4-5 day oscillation while in mean westerlies (as in the Indian Ocean during northern summer) it results in the quasi-biweekly mode.
|Item Type:||Journal Article|
|Additional Information:||Copyright of this article belongs to American Geophysical Union.|
|Department/Centre:||Division of Mechanical Sciences > Centre for Atmospheric & Oceanic Sciences|
|Date Deposited:||11 Dec 2006|
|Last Modified:||27 Apr 2011 06:31|
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