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Abstract The Gulf of Mexico (GoM) coast has experienced an acceleration of sea‐level rise between about 2010 and 2020, garnering notable attention from both the scientific and coastal communities. This study investigates the underlying causes of this acceleration by comparing high‐resolution (HR) and low‐resolution (LR) ensembles of multi‐year prediction simulations and historical climate simulations. The findings demonstrate that HR outperforms LR in predicting this acceleration, although they perform comparable prediction skill caused by external forcings. As the acceleration was driven by internal dynamics rather than external climate forcings, improved prediction skill in HR is attributed to its enhanced ability to capture internal variability. Further analysis reveals a strong link between GoM sea‐level variability and a dipole‐like wind stress curl anomaly straddling the region around Cuba, generating Ekman pumping and suction, and triggering remote changes in GoM sea‐level rise through Rossby wave propagation. HR effectively captures this process likely due to its improved prediction of the multi‐year Atlantic Meridional Mode.
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Exceptional multi-year prediction skill of the Kuroshio Extension in the CESM high-resolution decadal prediction system
Abstract The Kuroshio Extension (KE) has far-reaching influences on climate as well as on local marine ecosystems. Thus, skillful multi-year to decadal prediction of the KE state and understanding sources of skill are valuable. Retrospective forecasts using the high-resolution Community Earth System Model (CESM) show exceptional skill in predicting KE variability up to lead year 4, substantially higher than the skill found in a similarly configured low-resolution CESM. The higher skill is attained because the high-resolution system can more realistically simulate the westward Rossby wave propagation of initialized ocean anomalies in the central North Pacific and their expression within the sharp KE front, and does not suffer from spurious variability near Japan present in the low-resolution CESM that interferes with the incoming wave propagation. These results argue for the use of high-resolution models for future studies that aim to predict changes in western boundary current systems and associated biological fields.
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- Award ID(s):
- 2231237
- PAR ID:
- 10492380
- Publisher / Repository:
- Nature
- Date Published:
- Journal Name:
- npj Climate and Atmospheric Science
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2397-3722
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1038/s41612-023-00444-w
