Two sessions were organized during the 2018 Fall AGU Meeting entitled, (1) Coastal Response to Extreme Events: Fidelity of Model Predictions of Surge, Inundation, and Morphodynamics and (2) Improved Observational and Modeling Skills to Understand the Hurricane and Winter Storm Induced Surge and Meteotsunami. The focus of these sessions was on examining the impact of natural disasters on estuarine and coastal regions worldwide, including the islands and mainland in the northwestern Atlantic and the northwestern Pacific. The key research interests are the investigations on the regional dynamics of storm surges, coastal inundations, waves, tides, currents, sea surface temperatures, storm inundations and coastal morphology using both numerical models and observations during tropical and extratropical cyclones. This Special Issue (SI) ‘Estuarine and coastal natural hazards’ in Estuarine Coastal and Shelf Science is an outcome of the talks presented at these two sessions. Five themes are considered (effects of storms of wave dynamics; tide and storm surge simulations; wave-current interaction during typhoons; wave effects on storm surges and hydrodynamics; hydrodynamic and morphodynamic responses to typhoons), arguably reflecting areas of greatest interest to researchers and policy makers. This synopsis of the articles published in the SI allows us to obtain a better understanding of the dynamics of natural hazards (e.g., storm surges, extreme waves, and storm induced inundation) from various physical aspects. The discussion in the SI explores future dimensions to comprehend numerical models with fully coupled windwave- current-morphology interactions at high spatial resolutions in the nearshore and surf zone during extreme wind events. In addition, it would be worthwhile to design numerical models incorporating climate change projections (sea level rise and global warming temperatures) for storm surges and coastal inundations to allow more precisely informed coastal zone management plans.
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Extreme sea levels along coastal China: uncertainties and implications
Abstract Extreme sea levels (ESLs) due to typhoon-induced storm surge threaten the societal security of densely populated coastal China. Uncertainty in extreme value analysis (EVA) for ESL estimation has large implications for coastal communities’ adaptation to natural hazards. Here we evaluate uncertainties in ESL estimation and relevant driving factors based on hourly observations from 13 tide gauge stations and a complementary dataset derived from a hydrodynamic model. Results indicate significant uncertainties in ESL estimations stemming from using different EVA methods, which then propagate to the inundation assessment. Amplification factors due to sea-level rise (SLR) are highly sensitive to local relative SLR and the shape of the exceedance probability curve, which in turn depends on the selected EVA method. The hydrodynamic model hindcast indicates that high ESLs mainly occurred in eastern coastal China due to typhoon-induced storm surge. Larger uncertainties in the modelled ESLs are found for the coasts of the Yangtze River Delta, and particularly in the river mouth region. Future research and adaptation planning should prioritize these regions given expected future rising sea level, compound flood events, and human-induced factors (e.g. subsidence). This study provides theoretical and practical references for adaptation to ESL-related hazards along coastal China, with implications for coastal regions worldwide.
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- Award ID(s):
- 1854896
- PAR ID:
- 10225399
- Date Published:
- Journal Name:
- Stochastic Environmental Research and Risk Assessment
- Volume:
- 35
- Issue:
- 2
- ISSN:
- 1436-3240
- Page Range / eLocation ID:
- 405 to 418
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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