@article{gharagozlou_dietrich_massey_anderson_gorski_overton_2021, title={Formation of a barrier island breach and its contributions to lagoonal circulation}, volume={262}, ISSN={["1096-0015"]}, url={http://dx.doi.org/10.1016/j.ecss.2021.107593}, DOI={10.1016/j.ecss.2021.107593}, abstractNote={Barrier islands are a primary coastal defense and often experience erosion during storms. When they fail due to storm-induced breaching, there can be significant changes to the small- and large-scale hydrodynamics and morphodynamics of the region. In this study, we explore the formation of a breach on Hatteras Island, North Carolina, during Isabel (2003) and the subsequent flooding into Pamlico Sound. Two-way coupling of high-fidelity, high-resolution numerical models for coastal erosion and flooding enables a better understanding of the formation of the breach, as well as scenarios of the breach’s effects on the circulation in the region. The breach connecting the ocean to the sound formed during the day of landfall. It is shown that, during the storm, overwash and inundation from the ocean led to deterioration of the beach and dunes, and then after the storm, the creation of channels through the island was sensitive to elevated water levels in the lagoon. Then flooding scenarios are considered in which the ground surface of the hydrodynamic model was (a) static, updated with the (b) pre- and post-storm observations, and updated dynamically with (c) erosion model predictions and (d) erosion model predictions with elevated lagoon-side water levels. The model results show that the breach has region-scale effects on flooding that extend 10 to 13 km into the lagoon, increasing the local water levels by as much as 1 . 5 m . These results have implications for similar island-lagoon systems threatened by storms. • A storm-induced barrier-island breach is predicted with high-resolution models. • Ocean-side overwash and inundation led to beach and dune erosion during the storm. • Channel formation is sensitive to elevated sound-side water levels after the storm. • Erosion and circulation predictions are coupled to assess effects on region scales. • Breach allows flows 10–13 km into the lagoon, increases water depths by 1.5 m.}, journal={ESTUARINE COASTAL AND SHELF SCIENCE}, publisher={Elsevier BV}, author={Gharagozlou, Alireza and Dietrich, J. Casey and Massey, T. Chris and Anderson, Dylan L. and Gorski, Jessica F. and Overton, Margery F.}, year={2021}, month={Nov} }
 @article{gharagozlou_dietrich_karanci_luettich_overton_2020, title={Storm-driven erosion and inundation of barrier islands from dune-to region-scales}, volume={158}, ISSN={["1872-7379"]}, url={http://dx.doi.org/10.1016/j.coastaleng.2020.103674}, DOI={10.1016/j.coastaleng.2020.103674}, abstractNote={Barrier islands are susceptible to erosion, overwash, and breaching during intense storms. However, these processes are not represented typically in large-domain models for storm surge and coastal inundation. In this study, we explore the requirements for bridging the gap between dune-scale morphodynamic and region-scale flooding models. A high-resolution XBeach model is developed to represent the morphodynamics during Hurricane Isabel (2003) in the North Carolina (NC) Outer Banks. The model domain is extended to more than 30km of Hatteras Island and is thus larger than in previous studies. The predicted dune erosion is in good agreement with post-storm observed topography, and an ‘‘excellent’’ Skill Score of 0.59 is obtained on this large domain. Sensitivity studies show the morphodynamic model accuracy is decreased as the mesh spacing is coarsened in the cross-shore direction, but the results are less sensitive to the alongshore resolution. A new metric to assess model skill, Water Overpassing Area (WOA), is introduced to account for the available flow pathway over the dune crest. Together, these findings allow for upscaled parameterizations of erosion in larger-domain models. The updated topography, obtained from XBeach prediction, is applied in a region-scale flooding model, thus allowing for enhanced flooding predictions in communities along the Outer Banks. It is found that, even using a fixed topography in region-scale model, the flooding predictions are improved significantly when post-storm topography from XBeach is implemented. These findings can be generalized to similar barrier island systems, which are common along the U.S. Gulf and Atlantic coasts.}, journal={COASTAL ENGINEERING}, author={Gharagozlou, Alireza and Dietrich, Joel Casey and Karanci, Ayse and Luettich, Richard A. and Overton, Margery F.}, year={2020}, month={Jun} }