Abstract
We perform the first global analysis of storm surge seasonality using surge data from a global hydrodynamic model with full coverage of coastal areas, providing valuable insights for regions not represented in alternative observational data sources. We apply directio
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Abstract
We perform the first global analysis of storm surge seasonality using surge data from a global hydrodynamic model with full coverage of coastal areas, providing valuable insights for regions not represented in alternative observational data sources. We apply directional statistics based on the mixture model of the von Mises‐Fisher distribution to identify surge seasons and their characteristics. Results reveal that nearly half of the global coastal stations, predominantly in tropical and subtropical regions, either lack a distinct surge season or experience heightened surge activity across multiple periods. Furthermore, the seasonality of storm surges follows a consistent large‐scale spatial pattern tied to regional atmospheric variables. Spatial variability in the length of surge seasons is minimal in regions with bimodal surge seasons; however, the variability of surge peaks differs. Lastly, the seasonal distribution of storm surges differs regionally due to the underlying storm regime. These results provide valuable insights into the seasonality of storm surges on a global scale, which is useful for coastal risk management.
Plain Language Summary
Storm surges, the abrupt rise in sea levels above tidal elevations during a storm, are among the most devastating causes of coastal flooding globally. However, they are influenced by seasonal variations in atmospheric processes, which can amplify their peaks. In this study, we analyzed when these peaks typically occur and how the seasons vary spatially over a consistent period globally. By using surge data from a global hydrodynamic model with comprehensive geographical coverage, we provide insights for regions that lack observations from alternative data sources such as tide gauges. We show that the seasonality of surge peaks is not confined to a single well‐defined season globally. Some regions lack clear seasons, while others have well‐defined seasons with varying numbers. This means that some regions have more pronounced seasonal cycles than others. Despite this variation, the seasonal patterns are regionally coherent and are tied to underlying atmospheric patterns. Understanding these seasonal patterns could help improve coastal management plans, especially in places with extended surge risk windows