Assessing the Relative Coastal Vulnerability of National Park Units to Sea Level Rise and Lake Level Changes
The National Park Service (NPS) manages about 7,500 miles of shoreline in its various units throughout the United States. Since 2001, the NPS Geologic Resources Division has partnered with the U.S. Geological Survey (USGS) to conduct sea level rise and lake level change hazard assessments for 23 coastal NPS sites.
The NPS manages 392 national parks and 40 national heritage sites over 84 million acres throughout the states and territories of the United States. Of these, the NPS manages about 7,500 miles of shoreline. Sea level rise associated with global climate change will likely result in increased coastal erosion, salinization of water supplies, flooding, and wetland inundation in coastal areas. Lake level changes in the Great Lakes region will likely occur because of changes in precipitation patterns and extremes. The NPS Geologic Resources Division and the USGS have been conducting sea level rise and lake level change hazard assessments for NPS units since 2001.
The project involves creating maps of vulnerable areas through a coastal vulnerability index (CVI) to assist the NPS manage its protected areas in the face of rising sea levels. The CVI allows scientists to quantify potential physical changes to the shoreline from sea level rise. The criteria used in the assessment include six different variables that affect coastal vulnerability such as: tidal range and wave height, which contribute to inundation risk; coastal slope, which contributes to the susceptibility of the shoreline to flooding and rate of shoreline retreat or advance; historic shoreline change, which indicates erosion/accretion rates over time; geomorphology, which indicates relative erodability; and historical sea level rise rates, which indicate the correlation between eustatic sea level rise and tectonic uplift or subsidence. The CVI examines vulnerability in relation to the coast’s natural adaptive ability to adjust to sea level rise in order to find a relative measure of the shoreline’s natural vulnerability to sea level rise.
The project includes assessments of the following National Park units:
- Glacier Bay National Park and Preserve (Alaska)
- Kenai Fjords National Park (Alaska)
- Assateague Island National Seashore (Maryland/Virginia)
- Cape Cod National Seashore (Massachusetts)
- Cape Hatteras National Seashore (North Carolina)
- Cumberland Island National Seashore (Georgia)
- Fire Island National Seashore (New York)
- Gateway National Recreation Area (New York/New Jersey)
- Apostle Islands National Lakeshore (Wisconsin)
- Indiana Dunes National Lakeshore (Illinois)
- Sleeping Bear Dunes National Lakeshore (Michigan)
- Dry Tortugas National Park (Florida)
- Gulf Islands National Seashore (Florida/Mississippi)
- Padre Island National Seashore (Texas)
- Virgin Islands National Park (Virgin Islands)
- Channel Islands National Park (California)
- Golden Gate National Recreation Area (California)
- Olympic National Park (Washington)
- Point Reyes National Seashore (California)
- Kaloko-Honokōhau National Historical Park (Hawaii)
- National Park of American Samoa (American Samoa)
- War in the Pacific National Historical Park (Guam)
Outcomes and Conclusions
CVI assessments for each park are available here. These assessments are being used to inform long-term management decisions and to assess long-term threats to natural and cultural resources in NPS coastal units.
Gregg, R. M. (2020). Assessing the Relative Coastal Vulnerability of National Park Units to Sea Level Rise and Lake Level Changes [Case study on a project of the National Park Service - Geologic Resources Division and the U.S. Geological Survey - Woods Hole]. Version 2.0. Product of EcoAdapt’s State of Adaptation Program. Retrieved from CAKE: https://www.cakex.org/case-studies/assessing-relative-coastal-vulnerability-national-park-units-sea-level-rise-and-lake-level-changes (Last updated April 2020)