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Abstract Tropical cyclone (TC) impacts along the western Atlantic and Caribbean margin are not spatially uniform. Proxy based reconstructions of Common Era TC activity highlight this non‐uniform distribution at centennial‐millennial timescales. However, the sparse geographic scope of these reconstructions impedes our assessment of TC landfalls across broader spatial domains. This work presents a compilation of new and existing TC reconstructions from the Yucatan Peninsula for comparison with a contemporaneous compilation from New England, showing that these regions occupy distal nodes of a low‐frequency TC dipole. Increased Yucatan (New England) storminess is closely linked to intervals of Northern Hemisphere warming (cooling) and the expansion (contraction) of the Intertropical Convergence Zone, suggesting that secular shifts in the mean climate state mediate dipole orientation.
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Multi‐Centennial Spatial Coherency Among Atlantic Tropical Cyclones From Simulated and Reconstructed Storm Records
Abstract Proxy‐based reconstructions of long‐term Atlantic tropical cyclone (TC) variability reveal low‐frequency oscillations in regional TC landfalls over the Common Era. However, the limited spatial coverage and increased uncertainty of the proxy records complicates assessments of this feature. Here we present a new multi‐ensemble set of synthetic TCs downscaled from the Last Millennium Reanalysis project, which is based on sea surface temperatures that more accurately reflect past conditions. Throughout ensemble members, there are coherent multi‐centennial shifts in landfalls with persistent intervals of increased (decreased) occurrence along the eastern US concurrent with inverse activity in the southwest Caribbean and Gulf of Mexico, associated with basin‐scale redistributions of storm tracks. The emergent TC‐dipole from modeled climate provides context and support for its presence within proxy‐reconstructions. Furthermore, dipole recurrence across ensembles demonstrates that it arises from sea surface temperature‐informed climate processes. However, timing differences between ensembles indicate that transient atmospheric variability influences dipole position.
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- PAR ID:
- 10642556
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 18
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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