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Title: The MJO-QBO Relationship in a GCM with Stratospheric Nudging
Abstract Observational studies show a strong connection between the intraseasonal Madden-Julian oscillation (MJO) and the stratospheric quasi-biennial oscillation (QBO): the boreal winter MJO is stronger, more predictable, and has different teleconnections when the QBO in the lower stratosphere is easterly versus westerly. Despite the strength of the observed connection, global climate models do not produce an MJO-QBO link. Here the authors use a current-generation ocean-atmosphere coupled NASA Goddard Institute for Space Studies global climate model (Model E2.1) to examine the MJO-QBO link. To represent the QBO with minimal bias, the model zonal mean stratospheric zonal and meridional winds are relaxed to reanalysis fields from 1980-2017. The model troposphere, including the MJO, is allowed to freely evolve. The model with stratospheric nudging captures QBO signals well, including QBO temperature anomalies. However, an ensemble of nudged simulations still lacks an MJO-QBO connection.  more » « less
Award ID(s):
2020305
PAR ID:
10228899
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of Climate
ISSN:
0894-8755
Page Range / eLocation ID:
1 to 69
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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