News: Connecting Erosion to Flooding

2019/04/26 – NC Sea Grant Coastwatch Currents
Model Predicts Storm Impacts on Beaches and Dunes

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During storms, strong waves and currents can erode beaches and dunes and create low-lying areas vulnerable to flooding. We use field surveys and a computer model called XBeach to predict this erosion, as well as to understand its interactions with storm-driven flooding of larger regions.

Computer models allow us to see how the storm surge and waves impact the beach over time, and which locations are vulnerable to large-scale damage. Good predictions of such storm impacts help emergency managers take better-informed measures to protect coastal areas. Understanding vulnerabilities also instructs highway access design and residential area planning.

We used the XBeach computer model on more than 30 kilometers of Hatteras Island between Avon and Rodanthe to explore how to connect erosion predictions to larger areas. Could XBeach cover more of the island, yet still provide good erosion predictions at beach and dune scales? And how could we connect erosion predictions to other models for storm surge and flooding?

Presentation: HPC User Research Symposium

Alireza Gharagozlou wins Student Educational Award

Ph.D. student Alireza Gharagozlou won the Student Educational Award at the ASBPA National Coastal Conference 2018. This award is given annually to an undergraduate or graduate student who, through his or her research, is furthering the state of the science of coastal systems as it relates to the goals and mission of the ASBPA. Congrats to Alireza!

Alireza accepts the Student Educational Award during the awards luncheon at the ASBPA National Coastal Conference.

Coupling of Inlet-Scale Erosion and Region-Scale Flooding Predictions

The goals of this project are to better understand the storm-induced erosion of barrier islands, and to develop ways to represent that erosion in predictive models on large domains. The critical objectives will be: (1) Develop a high-resolution hindcast of inlet creation in a barrier island system, (2) Explore the sensitivity of erosion predictions to the quality of input data, and (3) Implement a two-way coupling of small-scale erosion to larger-scale flooding. As a study area, we will consider the erosion of Hatteras Island during Hurricane Isabel (2003) and the creation of the so-called Isabel Inlet. The model will be validated with aerial surveys of island topography, collected immediately before and after the storm. We will quantify the model’s ability to predict the inlet creation given coarse inputs, and identify the necessary resolution to include this process in larger-domain models. The evolving ground surface will be used to update topography in a region-scale flooding model, to examine how flow through the Isabel Inlet affected the back side of the island.

JC Dietrich. “Coupling of Inlet-Scale Erosion and Region-Scale Flooding Predictions.” U.S. Coastal Research Program, Storm Processes and Impacts Workshop, Technology Challenge, 2018/09/23 to 2019/09/22, $59,950 (Dietrich: $59,950).

Presentation: NSF Workshop 2018