Eastward-Moving Disturbance near the Tropopause along the Equator during the TOGA COARE IOP

Abstract

The three eastward-moving disturbances localized near the tropopause during January and February 1993 were investigated using JMA (Japan Meteorological Agency) global analysis data and the rawinsonde data at some stations during the TOGA COARE IOP (November 1992-February 1993). These events are considered to be part of the equatorial trapped internal Kelvin waves with upward energy propagation. These waves have large amplitude only in the several ten degree longitudes around the western Pacific. In January, the wave form is far from a sinusoidal one when the amplitude becomes very large. Change from the easterly to the westerly is much more rapid than change from the westerly to the easterly.