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Tropical cyclone (TC) models indicate that continued planet warming will likely increase the global proportion of powerful TCs (specifically Categories 4 and 5 hurricanes), increasingly jeopardizing low-lying coastal communities and resources such as the Pelican Cays, Belize. The combination of increased coastal development and continued relative sea-level rise puts these communities at even higher risk of damage from TCs. The short TC observational record for the western Caribbean hampers the extensive study of TC activity on centennial timescales, which hinders our ability to fully understand past TC climatology and improve the accuracy of TC models. To better assess TC risk, paleotempestological studies are necessary to put future scenarios in perspective. Here, we present a high-resolution reconstruction of coarser-grained sediment deposits associated with TC (predominately ≥ Category 2 hurricanes) passages over the past 1200 years from Elbow and Lagoon Cays, two coral reef-bounded lagoons at the northern and southern end of the Pelican Cays; the most southern Belizean paleotempestological site to date. Coincident timing of historic storms with statistically significant coarser-grained deposits within cay lagoon sediment cores allows us to determine which historic TCs likely generated event layers (tempestites) archived in the sediment record. Our compilation frequency analysis indicates one active interval (above-normal TC activity) from 1740-1950 CE and one quiet interval (below-normal TC activity) from 850-1018 CE. The active and quiet intervals in the Pelican Cays composite record are anticorrelated with those from nearby and re-analyzed TC records to the north, including the Great Blue Hole (∼100 km north) and the Northeast Yucatan (∼380 km northwest). This site-specific anticorrelation in TC activity along the western Caribbean indicates that we cannot rely on any one single TC record to represent regional TC activity. However, we cannot discount that these anticorrelated periods between the western Caribbean sites are due to randomness. To confirm that the anticorrelation in TC activity among sites from the western Caribbean is indeed a function of climate change and not randomness, an integration of more records and TC model simulations over the past millennium is necessary to assess the significance of centennial-scale variability in TC activity recorded in reconstructions from the western Caribbean.
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Evolving Tropical Cyclone Tracks in the North Atlantic in a Warming Climate
Abstract Tropical cyclone (TC) track characteristics in a changing climate remain uncertain. Here, we investigate the genesis, tracks, and termination of >35,000 synthetic TCs traveling within 250 km of New York City (NYC) from the pre‐industrial era (850–1800 CE) to the modern era (1970–2005 CE) to the future (2080–2100 CE). Under a very high‐emissions scenario (RCP8.5), TCs are more likely to form closer to the United States (U.S.) southeast coast (>15% increase), terminate in the northeastern Atlantic (>6% increase), and move most slowly along the U.S. Atlantic coast (>15% increase) from the pre‐industrial to future. Under our modeled scenarios, TCs are more likely to travel within 100 km of Boston, MA, USA (p = 0.01) and Norfolk, VA, USA (p = 0.05) than within 100 km of NYC in the future. We identify reductions in the time between genesis and the time when TCs come within 100 km of NYC, Boston, or Norfolk, as well as increased duration of TC impacts from individual storms at all three cities in the future.
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- Award ID(s):
- 1663807
- PAR ID:
- 10448395
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Earth's Future
- Volume:
- 9
- Issue:
- 12
- ISSN:
- 2328-4277
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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