Rising Seas and Stronger Storms Threaten Barrier Island Systems

As sea levels rise and storms intensify, these narrow stretches of sand and vegetation that buffer coastlines will be exposed to more frequent and severe flooding, erosion, and water table changes.

The study’s findings, focusing on Cape Lookout, project that with a sea-level rise (SLR) of just 0.5 meters, nearly half of the current land area of the islands will flood daily, with the impact worsening during storms. Even a moderate one-year storm could flood up to 74% of the barrier island area, while more powerful storms with a 20-year return interval could submerge more than 85% of the islands.

In addition to flooding, shallow and emerging groundwater poses a growing challenge, as the water table across the islands is already shallow—often less than two meters deep. As sea levels continue to rise, groundwater will rise as well, reaching the land surface in many locations, increasing the risk of flooding from within. The islands are also retreating at alarming rates: with a projected one-meter rise in sea levels, shoreline retreat could average 178 meters, which is more than 60% of the island width at its narrowest points.