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Title: The Tropical Pacific ENSO–Mean State Relationship in Climate Models over the Last Millennium
Abstract ENSO and the mean zonal sea surface temperature gradient (dSST) of the tropical Pacific are important drivers of global climate and vary on decadal to centennial time scales. However, the relationship between dSST and ENSO cannot be assessed with the short instrumental record, and is uncertain in proxy data, with intervals of both stronger and weaker ENSO postulated to occur with overall strong dSST in the past. Here we assess the ENSO–dSST relationship during the last millennium using general circulation models (GCMs) participating in phase 3 of the Paleoclimate Modeling Intercomparison Project. Last millennium GCM simulations show diversity in the strength and direction of the ENSO–dSST relationship. Yet, the models that best simulate modern tropical Pacific climate frequently have a more negative ENSO–dSST correlation. Thus, last millennium tropical Pacific climate simulations support the likelihood of enhanced ENSO during decadal to centennial periods of reduced tropical Pacific dSST. However, the alternating directional ENSO–dSST relationship in all model simulations suggests that this relationship is not constant through time and is likely controlled by multiple mechanisms.  more » « less
Award ID(s):
1602580
PAR ID:
10194943
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of Climate
Volume:
33
Issue:
17
ISSN:
0894-8755
Page Range / eLocation ID:
7539 to 7551
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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