Breaching or overwash deposition? Field and model analysis of barrier morphologic response to storms.
Summary
Barrier islands are thin and low-lying stretches of land vulnerable to storm impacts. Storms can cause barrier breaching but also washover deposition, these widely different outcomes remain difficult to predict. Here we use the hydrologic and morphologic model, Delft3D, to get an indication of the controlling factors of barrier breaching and washover deposition. We simulate different barrier island morphologies, land cover, and storm characteristics. From the model simulations we found that both an increase in dune height and amount of island development can reduce the breaching potential. The model results are compared against observations from hurricane Sandy. The 24 washovers and 4 breaches that formed during Hurricane Sandy show good agreement with the model results.