Extremes of the Indian summer monsoon rainfall, ENSO and equatorial Indian Ocean oscillation

Gadgil, Sulochana and Vinayachandran, PN and Francis, PA and Gadgil, Siddhartha (2004) Extremes of the Indian summer monsoon rainfall, ENSO and equatorial Indian Ocean oscillation. In: Geophysical Research Letters, 31 (12). L12213-1-4.

Preview

PDF extremes.pdf Download (247kB)

Abstract

It is well known that anomalies of the Indian Summer Monsoon Rainfall (ISMR) are linked to El Nino and Southern Oscillation (ENSO). We show that large anomalies of the ISMR are also linked to the Equatorial Indian Ocean Oscillation (EQUINOO) between states with enhancement/ suppression of atmospheric convection over the western part of the equatorial Indian Ocean with suppression/enhancement over the eastern part and associated changes in the anomaly of the zonal wind along the equator. EQUINOO is the atmospheric component of the coupled Indian Ocean Dipole mode. There is a strong relation between the large anomalies of ISMR and a composite index which is a linear combination of the indices for ENSO and EQUINOO with all seasons with large deficits ( excess) characterized by small ( large) values of the index.However, the variation of ISMR within one standard deviation is more complex and does not appear to be related to the composite index.

Item Type:	Journal Article
Publication:	Geophysical Research Letters
Publisher:	American Geophysical Union
Additional Information:	The copyright of this article belongs to American Geophysical Union.
Keywords:	Tropical meteorology;Drought;Oceanography;Climate and interannual variability;Indian Ocean
Department/Centre:	Division of Mechanical Sciences > Centre for Atmospheric & Oceanic Sciences
Date Deposited:	25 Oct 2004
Last Modified:	19 Sep 2010 04:16
URI:	http://eprints.iisc.ac.in/id/eprint/2116

Actions (login required)

View Item