Coupled ocean-temperature dynamics in the Indian Ocean during 1997-98

Citation
Pj. Webster et al., Coupled ocean-temperature dynamics in the Indian Ocean during 1997-98, NATURE, 401(6751), 1999, pp. 356-360
Citations number
22
Categorie Soggetti
Multidisciplinary,Multidisciplinary,Multidisciplinary
Journal title
NATURE
ISSN journal
00280836 → ACNP
Volume
401
Issue
6751
Year of publication
1999
Pages
356 - 360
Database
ISI
SICI code
0028-0836(19990923)401:6751<356:CODITI>2.0.ZU;2-5
Abstract
Climate variability in the Indian Ocean region seems to be, in some aspects , independent of forcing by external phenomena such as the El Nino/Southern Oscillation(1-4). But the extent to which, and how, internal coupled ocean -atmosphere dynamics determine the state of the Indian Ocean system have no t been resolved. Here we present a detailed analysis of the strong seasonal anomalies in sea surface temperatures, sea surface heights, precipitation and winds that occurred in the Indian Ocean region in 1997-98, and compare the results with the record of Indian Ocean climate variability over the pa st 40 years. We conclude that the 1997-98 anomalies-in spite of the coincid ence with the strong El Nino/Southern Oscillation event-may primarily be an expression of internal dynamics, rather than a direct response to external influences. We propose a mechanism of ocean-atmosphere interaction governi ng the 1997-98 event that may represent a characteristic internal mode of t he Indian Ocean climate system. In the Pacific Ocean, the identification of such a mode has led to successful predictions of El Nino(5); if the propos ed Indian Ocean internal mode proves to be robust, there may be a similar p otential for predictability of climate in the Indian Ocean region.