National Assessment of Coastal Vulnerability to Sea-Level Rise: Preliminary Results for the U.S. Atlantic Coast

Summary

The coastal vulnerability index (CVI) provides insight into the relative potential of coastal change due to future sea-level rise. The maps and data presented here can be viewed in at least two ways:

• as a base for developing a more complete inventory of variables influencing the coastal vulnerability to future sea-level rise to which other elements can be added as they become available; and
• as an example of the potential for assessing coastal vulnerability to future sea-level rise using objective criteria.

As ranked in this study, coastal geomorphology is the most important variable in determining the CVI. Coastal slope, wave height, relative sea-level rise, and tide range provide large-scale variability to the coastal vulnerability index. Erosion and accretion rates contribute the greatest variability to the CVI at short (~3 km) spatial scales. The rates of shoreline change, however, are the most complex and poorly documented variable in this data set. The rates used here are based on a dated, low-resolution data set and thus far corrections have been made only on a preliminary level. To best understand where physical changes may occur, large-scale variables must be clearly and accurately mapped, and small-scale variables must be understood on a scale that takes into account their geologic, environmental, and anthropogenic influences.