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Abstract Here we investigate the role of the atmospheric circulation in the Atlantic Meridional Overturning Circulation (AMOC) by comparing a fully‐coupled large ensemble, a forced‐ocean simulation, and new experiments using a fully‐coupled global climate model where winds above the boundary layer are nudged toward reanalysis. When winds are nudged north of 45°N, agreement with RAPID array observations of AMOC at 26.5°N improves across several metrics. The phasing of interannual variability is well‐captured due to the response of the local Ekman component in both wind‐nudging and forced‐ocean simulations, however the variance remains underestimated. The mean AMOC strength is substantially reduced relative to the fully‐coupled model large ensemble, which is biased high, due to the impact of winds on surface buoyancy fluxes over the subpolar gyre. Nudging winds toward observations also reduces the 1979–2016 trend in AMOC, suggesting that improvement in the representation of the high‐latitude atmosphere is important for projecting long‐term AMOC changes.
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This content will become publicly available on July 16, 2026
Enhancing winter climate simulations of the Great Lakes: Insights from a new coupled lake-ice-atmosphere (CLIAv1) model on the importance of integrating 3D hydrodynamics with a regional climate model
- Award ID(s):
- 2435005
- PAR ID:
- 10653497
- Publisher / Repository:
- Geoscientific Model Development
- Date Published:
- Journal Name:
- Geoscientific Model Development
- ISSN:
- 1991-9603
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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