Impact of freshening over the Southern Ocean on ENSO

Abstract The response of El Niño‐Southern Oscillation ( ENSO ) to idealized freshwater forcing over the Southern Ocean ( SO ) is investigated using a fully‐coupled climate model. Modeling results explicitly show that freshening over the SO can modulate mean climate of tropical Pacific, triggering La...

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Bibliographic Details
Published in:Atmospheric Science Letters
Main Authors: Ma, Hao, Wu, Lixin, Li, Zhengquan
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2013
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Online Access:http://dx.doi.org/10.1002/asl2.410
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fasl2.410
https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1002/asl2.410
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Summary:Abstract The response of El Niño‐Southern Oscillation ( ENSO ) to idealized freshwater forcing over the Southern Ocean ( SO ) is investigated using a fully‐coupled climate model. Modeling results explicitly show that freshening over the SO can modulate mean climate of tropical Pacific, triggering La Niña‐like sea surface temperature ( SST ) anomalies and a sharper zonal tilt of tropical thermocline, which further influences ENSO variability. Amplitude of ENSO is intensified due to shallower thermocline in central‐eastern tropical Pacific, while the period of ENSO is significantly enlarged primarily because upper‐ocean meridional temperature gradient between equatorial and off‐equatorial region is decreased, which is favorable to extend the period of ENSO © 2012 Royal Meteorological Society .