We are developing a community modeling tool, based on field data, to inform impact and vulnerability assessments of dune and beach recovery following storms under a suite of sea level rise scenarios. The study represents collaboration between NOAA, Oregon State University, University of North Carolina, and the North Carolina Sentinel Site Cooperative and is focused on managed (Bogue Banks) and natural (Cape Lookout National Seashore) beaches in North Carolina.
Why We Care
Sandy beaches and dunes provide critical ecosystem services as the first line of defense against inundation from storms, conservation for native species, and are a major attraction for recreation. The amounts of services provided, particularly as natural infrastructure for coastal protection, are related to the interaction among vegetation and sediment, and are influenced by water level (including sea level rise), storm intensity and frequency, often competing human activities such as development, conservation, beach replenishment, and recreation. Effective coastal management requires an understanding of the relationship among these processes and possible trade-offs in ecosystem services required for climate change adaptation.
What We Are Doing
This project will improve management effectiveness of coastal areas through the development of a dynamic predictive tool of beach/dune function and recovery following storms. This new tools will integrate three existing model platforms, XBeach, CDM (Coastal Dune Model), and a wind transport model to allow for incorporation of dynamic feedback processes among physical and biological processes. To inform the new model, extensive field measurements will be made on Cape Lookout National Seashore (North Core, South Core, and Shackleford Banks) and Bogue Banks (including the towns of Atlantic Beach, Pine Knoll Shores, and Emerald Isle). Measurements on the relationship between vegetation composition and dune morphology will inform the dynamic modeling tool and allow for assessments of climate change and management scenarios.
Specific management scenarios evaluated will be made in conjunction with the North Carolina Sentinel Site Cooperative and representatives from local and regional management entities. On Cape Lookout National Seashore, scenarios may include evaluation of provisions for natural dune recovery, engineering options, and conservation approaches (e.g., piping plover habitat) on coastal protection. On Bogue Banks, management scenarios will focus on options for optimizing beach nourishment and vegetation planting scheme to achieve dune goals.
Project Overview Video
What We’ve Accomplished
Possible beach and dune management actions to help managers make decisions in the context of natural beach and dune processes were evaluated and presented to the management advisory group. The team delivered guidance for the outer banks including three predictive metrics that identify dunes that will erode and require attention and those that are likely to build in size. The project evaluated the impact of sand fencing, dune grass planting, beach nourishment timing, and treatment of the wrack line on dune shape. The team revealed that sand fencing creates a wider shorter dune system which has implications on the protection and resilience of a dune during storm events. Planting dunes with the right grass species, allowing for a wrack line to remain on the beach, and nourishing beaches prior to the storm season, are other actions that were observed to lead to taller and wider dunes systems. This project did not produce a tool, though it delivered information and outputs in other ways to change thinking about how to manage beaches and dunes in a way that leverages natural processes. This project has resulted in 11 peer-reviewed publications.
The project is led by Professor Peter Ruggiero of Oregon State University, along with co-PI's, Professor Laura Moore of the University of North Carolina at Chapel Hill, and Professor Sally Hacker of Oregon State University, and is funded through the Effects of Sea Level Rise program.