Publication

Estuarine tidal response to sea level rise: The significance of entrance restriction

Résumé

Estuarine environments, as dynamic low-lying transition zones between rivers and the open sea, are vulnerable to sea level rise (SLR). To evaluate the potential impacts of SLR on estuarine responses, it is necessary to examine the altered tidal dynamics, including changes in tidal amplification, dampening, reflection (resonance), and deformation. Moving beyond commonly used static approaches, this study uses a large ensemble of idealised estuarine hydrodynamic models to analyse changes in tidal range, tidal prism, phase lag, tidal current velocity, and tidal asymmetry of restricted estuaries of varying size, entrance configuration and tidal forcing as well as three SLR scenarios. For the first time in estuarine SLR studies, data analysis and clustering approaches were employed to determine the key variables governing estuarine hydrodynamics under SLR. The results indicate that the hydrodynamics of restricted estuaries examined in this study are primarily governed by tidal forcing at the entrance and the estuarine length. In addition, SLR increases the average water depth and alters the nodal point location in a seaward direction, thereby significantly affecting tidal wave propagation patterns and reducing the degree of flood domination. In estuaries with restricted entrances, tidal range diminishes drastically in the restricted zone by 20–60%, and the maximum tidal current velocity is higher in the restricted part but lower in the upstream part compared to unrestricted estuaries. For estuary types examined, inundation extent under SLR will likely be greater than the extent expected through simply adjusting existing water levels upwards. The findings also underline that an engineered entrance restriction could regulate tidal wave propagation within an estuary to offset SLR induced tidal range amplification. However, this may pose additional management challenges.

À propos de ce résultat
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Graph Chatbot

Chattez avec Graph Search

Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.

AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.