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Title: An Investigation of the Ocean’s Role in Atlantic Multidecadal Variability
Abstract A mechanistic understanding of the Atlantic multidecadal variability (AMV) is highly desirable since it will considerably aid regional and global climate predictions. Although ocean dynamics have long been invoked to explain the AMV, recent studies have cast doubt on its influence. Here we evaluate the necessity of ocean dynamics for the AMV using an observationally based idealized model that isolates the contribution of atmospheric forcing to the AMV. By demonstrating that this model underestimates the magnitude of the observed sea surface temperature variability in the extratropical North Atlantic, we infer that ocean dynamics contribute significantly to the AMV in this region. This inference holds when we add anthropogenic aerosol forcing and the effects of mixed layer depth variability to the idealized model. Thus, our study suggests that ocean heat transport convergence is needed to explain sea surface temperature variability in the extratropical North Atlantic. Sustained ocean observing systems in the this region will help untangle the physical mechanisms involved.  more » « less
Award ID(s):
1948335
PAR ID:
10314722
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of Climate
Volume:
33
Issue:
8
ISSN:
0894-8755
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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