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Abstract Extreme sea-level events, such as those caused by tropical cyclones (TCs), pose significant risks to coastal areas. However, the current generation of climate models struggles to simulate these events due to coarse resolution. By comparing high-resolution (HR) and low-resolution (LR) Community Earth System Model simulations with tide gauge and altimeter data along the US. Gulf of Mexico (GoM) coast, we find that HR better represents both mean dynamic sea level (DSL) and daily mean extreme DSL (EDSL) statistics. In contrast, LR significantly underestimates the strength of EDSL mainly due to its deficiency in simulating strong TCs. Both observations and HR show larger daily mean EDSL on the western Gulf coast than on the eastern side, highlighting the need for HR climate simulations to improve coastal resilience planning.
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Multi‐Year Prediction of Accelerated Sea Level Rise Along the Gulf of Mexico Coast During 2010–2020
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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- PAR ID:
- 10662819
- Publisher / Repository:
- AGU
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 19
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2025GL116127
