Synoptic drivers of storm surge in Kotzebue Sound

Coastal flooding due to storm surge is a serious danger for communities and industry in western Alaska. The observed rise in sea level and decrease of sea ice cover acts to increase the risk of surge-related flooding. The purpose of this study is to gain an understanding of which storm tracks lead to the greatest surge, whether certain areas are more vulnerable than others due to local scale features, and what currents are associated with surge events. Kotzebue Sound was chosen as the area of focus on the basis of physical and social factors. Physically, its bathymetry, topography, and coastal orientation make it particularly susceptible to surge. Socially, this region possesses a range of affected coastal groups, including heavy industry and subsistence communities. The study was performed using the ADvanced CIRCulation (ADCIRC) coastal circulation and surge model forced with idealized storm scenarios.

Results from the study suggest the utility of applying a surge model to learn about water run up, set down and induced current on the Alaskan coast. Local flooding peculiarities were found in Hotham Inlet, which could have potential impacts on a sensitive ecosystem. Noticeable differences were found in surge magnitude and distribution between storms of different ground track speed, as well as small changes in track location.