Publication Date:
2022-05-25
Description:
Author Posting. © American Meteorological Society, 2012. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 25 (2012): 343–349, doi:10.1175/JCLI-D-11-00059.1.
Description:
The Equatorial Undercurrent (EUC) is a major component of the tropical Pacific Ocean circulation. EUC velocity in most global climate models is sluggish relative to observations. Insufficient ocean resolution slows the EUC in the eastern Pacific where nonlinear terms should dominate the zonal momentum balance. A slow EUC in the east creates a bottleneck for the EUC to the west. However, this bottleneck does not impair other major components of the tropical circulation, including upwelling and poleward transport. In most models, upwelling velocity and poleward transport divergence fall within directly estimated uncertainties. Both of these transports play a critical role in a theory for how the tropical Pacific may change under increased radiative forcing, that is, the ocean dynamical thermostat mechanism. These findings suggest that, in the mean, global climate models may not underrepresent the role of equatorial ocean circulation, nor perhaps bias the balance between competing mechanisms for how the tropical Pacific might change in the future. Implications for model improvement under higher resolution are also discussed.
Description:
KBK gratefully acknowledges the J. Lamar
Worzel Assistant Scientist Fund. GCJ is supported by
NOAA’s Office of Oceanic and Atmospheric Research. RM gratefully acknowledges the generous support
and hospitality of the Divecha Centre for Climate
Change and CAOS at IISc, Bangalore, and partial support
by NASA PO grants.
Description:
2012-07-01
Keywords:
Tropics
;
Ocean circulation
;
Ocean dynamics
;
Climate models
;
Coupled models
;
Ocean models
Repository Name:
Woods Hole Open Access Server
Type:
Article
Format:
application/pdf
