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Processes and boreal summer impacts of the 2004 El Nino Modoki: An AGCM study

Ashok, K and Iizuka, S and Rao, SA and Saji, NH and Lee, WJ (2009) Processes and boreal summer impacts of the 2004 El Nino Modoki: An AGCM study. Geophysical Research Letters, 36 (4).

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The sea surface temperature anomalies (SSTA) of tropical Pacific in the boreal summer of 2004 show a distinct tripolar pattern with warm SSTA in the central tropical Pacific, flanked on both sides by cold SSTA. The distinct conditions during the boreal summer of 2004 and the following winter were catalogued as a new coupled phenomenon named El Niño Modoki in a recent generalized study. The 2004 event is unique in the sense that it occurred without any co-occurring IOD, thereby without any possibility of external modulation of its processes and impacts in the tropics. Using observed data since 1979, we show that the 2004 event indeed involves the distinct equatorial coupled ocean-atmosphere dynamics different from the conventional El Niño. Further, using an AGCM, we confirm that during boreal summer anomalous twin Walker circulation cells associated with the El Niño Modoki SSTA give rise to observed rainfall anomalies in the tropics

Item Type: Article
Additional Information: Copyright of this article belongs to American Geophysical Union
Uncontrolled Keywords: Coupled phenomena; External modulation; Observed data; Ocean-atmosphere dynamics; Rainfall anomaly; Sea surface temperature anomalies; Walker circulation, Atmospheric temperature; Nickel compounds; Ocean engineering; Oceanography; Timing devices, Tropics, El Nino; sea surface temperature; temperature anomaly; Walker circulation, Pacific Ocean; Pacific Ocean (Central); Pacific Ocean (Tropical)
Subjects: Meteorology and Climatology
Depositing User: IITM Library
Date Deposited: 16 Feb 2015 15:19
Last Modified: 16 Feb 2015 15:19

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