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Abstract Future coastal flood hazard at many locations will be impacted by both tropical cyclone (TC) change and relative sea‐level rise (SLR). Despite sea level and TC activity being influenced by common thermodynamic and dynamic climate variables, their future changes are generally considered independently. Here, we investigate correlations between SLR and TC change derived from simulations of 26 Coupled Model Intercomparison Project Phase 6 models. We first explore correlations between SLR and TC activity by inference from two large‐scale factors known to modulate TC activity: potential intensity (PI) and vertical wind shear. Under the high emissions SSP5‐8.5, SLR is strongly correlated with PI change (positively) and vertical wind shear change (negatively) over much of the western North Atlantic and North West Pacific, with global mean surface air temperature (GSAT) modulating the co‐variability. To explore the impact of the joint changes on flood hazard, we conduct climatological–hydrodynamic modeling at five sites along the US East and Gulf Coasts. Positive correlations between SLR and TC change alter flood hazard projections, particularly at Wilmington, Charleston and New Orleans. For example, if positive correlations between SLR and TC changes are ignored in estimating flood hazard at Wilmington, the average projected change to the historical 100 years storm tide event is under‐estimated by 12%. Our results suggest that flood hazard assessments that neglect the joint influence of these factors and that do not reflect the full distribution of GSAT change may not accurately represent future flood hazard.
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A Global Analysis of Interannual Variability in Potential and Actual Tropical Cyclone Intensities
Abstract We examine the relationship between interannual variability of potential intensity (PI) and tropical cyclone (TC) actual intensity (AI) and the factors contributing to this variability across all global ocean basins. Using best‐track data and three reanalysis products from 1980–2016, we find that the Western North Pacific is the only basin that yields consistently significant correlations between AI and PI sampled along the TC tracks. In contrast to a previous study, the North Atlantic does not yield statistically significant correlations. This is because the correlation between AI and PI in the North Atlantic is sensitive to the length of the time period considered and the individual years within that time period. Both thermodynamic efficiency and air‐sea disequilibrium contribute to interannual variability in along‐track PI.
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- Award ID(s):
- 1663807
- PAR ID:
- 10375414
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 47
- Issue:
- 18
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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