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The brevity of the instrumental record limits our knowledge of tropical cyclone activity on multidecadal to longer timescales and hampers our ability to diagnose climatic controls. Sedimentary archives containing event beds provide essential data on tropical cyclone activity over centuries and millennia. This review highlights the advantages and limitations of this approach and how these reconstructions have illuminated patterns of tropical cyclone activity and potential climate drivers over the last millennium. Key elements to developing high-quality reconstructions include confident attribution of event beds to tropical cyclones, assessing the potential role of other mechanisms, and evaluating the potential influence of geomorphic changes, sea-level variations, and sediment supply on a settings’ susceptibility to event bed deposition. Millennium-long histories of severe tropical cyclone occurrence are now available from many locations in the western North Atlantic and western North Pacific, revealing clear regional shifts in activity likely related to intervals of large-scale ocean-atmosphere reorganization.▪Prior to significant human influence in Earth's climate, natural climate variability dramatically altered patterns of tropical cyclone activity.▪For some regions (e.g., The Bahamas and the Marshall Islands), earlier intervals of tropical cyclone activity exceeded what humans have experienced during the recent period of instrumental measurements (∼1850 CE–present).▪Risk assessments based on the short instrumental record likely underestimate the threat posed by tropical cyclones in many regions.▪Changes in atmospheric and oceanic circulation associated with the Little Ice Age (∼1400–1800 CE) resulted in significant regional changes in tropical cyclone activity.▪Given the past sensitivity of tropical cyclone activity to climate change, we should anticipate regional shifts in tropical cyclone activity in response to ongoing anthropogenic warming of the planet.
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This content will become publicly available on December 23, 2025
Diving Deeper: Leveraging the Chondrichthyan Fossil Record to Investigate Environmental, Ecological, and Biological Change
The extensive chondrichthyan fossil record spans 400+ million years and has a global distribution. Paleontological studies provide a foundation of description and taxonomy to support deeper forays into ecology and evolution considering geographic, morphologic, and functional changes through time with nonanalog species and climate states. Although chondrichthyan teeth are most studied, analyses of dermal denticle metrics and soft tissue imprints are increasing. Recent methodological advances in morphology and geochemistry are elucidating fine-scale details, whereas large datasets and ecological modeling are broadening taxonomic, temporal, and geographic perspectives. The combination of ecological metrics and modeling with environmental reconstruction and climate simulations is opening new horizons to explore form and function, demographic dynamics, and food web structure in ancient marine ecosystems. Ultimately, the traits and taxa that endured or perished during the many catastrophic upheaval events in Earth's history contribute to conservation paleobiology, which is a much-needed perspective for extant chondrichthyans.▪The longevity and abundance of the chondrichthyan fossil record elucidates facets of ecological, evolutionary, and environmental histories.▪Though lacking postcranial, mineralized skeletons, dental enameloid and dermal denticles exquisitely preserve morphology and geochemistry.▪Technical advances in imaging, geochemistry, and modeling clarify the linkages between form and function with respect to physiology, diet, and environment.▪Conservation efforts can benefit from the temporal and spatial perspective of chondrichthyan persistence through past global change events.
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- PAR ID:
- 10580162
- Publisher / Repository:
- Annual Reviews
- Date Published:
- Journal Name:
- Annual Review of Earth and Planetary Sciences
- ISSN:
- 0084-6597
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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