Coastal exposure analysis

National Fish and Wildlife Foundation
Map detail showing soil drainage in the Cape Fear River Basin

As sea levels rise and heavy precipitation events occur with increased intensity and frequency, many coastal communities—both human and natural—become more vulnerable to the impacts caused by our changing climate: coastal erosion, flooding, impaired water quality, and storm surge, to name a few.

Project handoutTo identify landscapes where community and natural assets are potentially exposed to damage caused by impacts of these climate hazards, NEMAC partnered with the National Fish and Wildlife Foundation to develop a strategy to increase the resilience of valued coastal communities and fish and wildlife habitats. 

Through the integration of GIS analysis and spatial modeling with a vulnerability assessment methodology, the resulting products aim to expand the understanding of coastal resilience needs for areas in North Carolina's Cape Fear River Basin—and also more broadly in the coastal watersheds of the South Atlantic, the North Atlantic, and the Gulf of Mexico—and can assist stakeholders in determining priority areas where valued assets are most vulnerable.

Identifying Exposure to Severe Storm and Flood Events

This analysis focuses on the concept of exposure, defined as the location of a community’s asset—such as a school, a home, or its people—in relation to an area potentially impacted by a threat or hazard. Community resilience (or vulnerability) to natural hazards and threats is dependent upon both exposure and the capacity the community has to cope.

To identify places where assets are most exposed to flood hazards, two models were created:

  • Threat Index: a model spatially depicting relevant hazards and their potential intensities
  • Community Asset Index: a model spatially depicting the presence and quantity of relevant assets

The two models were then combined to understand where and at what intensity assets are potentially impacted by hazards. The result of these combined models is the Exposure Index. Areas with the highest presence of threats and the highest presence of valued community assets were determined as being the most exposed. 

Inputs used to create the Threat and Asset Indices

Applying the Exposure Analysis

Using the Exposure Index, different landscape types—such as open spaces, protected areas, and human communities—can then be further analyzed to identify vulnerabilities to flooding and storm events. 

The following is a preview of the models created in this analysis:

Threat Index on the California Coast   Threat Index on the East and Gulf Coasts   

Community Asset Index on the California Coast   Community Asset Index on the East and Gulf Coasts

            Exposure Index for All Regions