Open AccessInteractive Feedback between ENSO and the Indian Ocean in an Interactive Ensemble Coupled Model
Author(s) -
JongSeong Kug,
Ben P. Kirtman,
Iksung Kang
Publication year - 2006
Publication title -
journal of climate
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.315
H-Index - 287
eISSN - 1520-0442
pISSN - 0894-8755
DOI - 10.1175/jcli3980.1
Subject(s) - kelvin wave , upwelling , climatology , geology , el niño southern oscillation , indian ocean , atmosphere (unit) , sea surface temperature , trade wind , ocean current , ocean general circulation model , walker circulation , pacific ocean , oceanography , atmospheric model , climate model , general circulation model , climate change , meteorology , geography
An interactive feedback between ENSO and the Indian Ocean is investigated using a Center for Ocean–Land–Atmosphere Studies (COLA) interactive ensemble coupled model. From a long-term simulation of the coupled GCM, it is shown that El Niño events terminate relatively rapidly when the Indian Ocean SST is anomalously warm. The anomalous Indian Ocean warming induces the anomalous easterlies over the western Pacific by modulating the Walker circulation. In turn, the anomalous easterlies generate oceanic-upwelling Kelvin waves over the western Pacific, which propagate eastward and accelerate the decay of the warm SST in the eastern Pacific. As a result, El Niño terminates relatively quickly, and the phase transition from El Niño to La Niña progresses rapidly. These interactive processes are consistent with those derived from the previous observational analyses.