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Read Full Article (file size: 205026 bytes) Cited by
GEOPHYSICAL RESEARCH LETTERS,
VOL. 30, NO. 18,
1964,
doi:10.1029/2003GL017564,
2003
On the termination of the 2002–03 El Niño event
Gabriel A. Vecchi
Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, Seattle, Washington, USA
D. E. Harrison
Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, Seattle, Washington, USA Pacific Marine Environmental Laboratory, NOAA, Seattle, Washington, USA
Abstract
Every new El Niño presents an opportunity to revisit our understanding of El Niño characteristics and processes. We examine
the extent to which the termination of the 2002–03 El Niño followed the scenario of
Harrison and Vecchi [1999]
, in which (1) there is a late-year southward shift of near-equatorial westerly wind anomalies, and (2) subsequent eastern
equatorial Pacific cold tongue thermocline shallowing is driven by the wind shift. There was a prominent late-year southward
shift in the low-frequency west Pacific zonal wind anomalies in 2002–03. Ocean general circulation model experiments establish
the shift as the primary cause of cold tongue thermocline shallowing. Reflected equatorial waves and local wind anomaly changes
are much less important. Successful theories and models of El Niño should address the processes that cause the year-end southward
wind shift. Interactions between anomalous El Niño conditions and the seasonal cycle of solar insolation may provide such
a process.
Received 18
April
2003;
accepted 28
August
2003;
published 27
September
2003.
Index Terms: 4522 Oceanography: Physical: El Nino; 4504 Oceanography: Physical: Air/sea interactions (0312); 1620 Global Change: Climate dynamics (3309); 4231 Oceanography: General: Equatorial oceanography; 3374 Meteorology and Atmospheric Dynamics: Tropical meteorology.
Read Full Article (file size: 205026 bytes) Cited by
Citation: Vecchi, G. A., and D. E. Harrison
(2003),
On the termination of the 2002–03 El Niño event,
Geophys. Res. Lett.,
30(18),
1964,
doi:10.1029/2003GL017564.
Copyright 2003 by the American Geophysical Union.
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