Atlantic coast. From to , sea levels rose up to 5 inches in some locales. These levels are the fastest in the past 2, years, and are considered a direct consequence of climate change. Rising sea levels could increase overwash from waves, cause significant erosion, and intensify flooding.
The barrier islands are equipped with natural defenses that buffer the inland shore against storms due to their unique formations.
Or at least they would if the same development that transformed the Outer Banks into a vacation wonderland hadn't jammed the machinery of island migration.
Before World War II, the people who lived in the islands' fishing communities built their houses on high ground, far from the ocean's edge, and traveled by boat. That started to change in the s, when paving began on State Highway To protect the road from storms, workers piled sand east of the highway on artificial dunes first built in the s.
When storms carved inlets through the road, engineers filled them. The dune-building and inlet-filling blocked the movement of sand across the islands.
On the ocean side, the islands kept eroding, but now they didn't grow on the sound side. So they narrowed. Other engineering projects meant to protect human activities, such as dredging and building hard structures called jetties and groins, made erosion worse, Riggs says. Even so, the road brought tourists, and a new economy developed around beachfront rental homes, hotels, and stores. The permanent population of Dare County, about 35,, is six times as large today as it was in —and the residents all have a stake in preserving the islands where they are.
The ultimate fate of the islands depends on how quickly the rise in sea level accelerates in the coming decades and how many major hurricanes slam the islands. Riggs predicts the lowest, narrowest islands could break up into a system of small, eroded island remnants and shoals.
Without human interference, the islands would adapt to accelerating sea-level rise by migrating west, says Duke's Pilkey. Instead, because of engineering projects, they're "standing perfectly still, and we're beating our head against the wall trying to hold those shorelines in place.
Riggs has proposed that the state remove portions of State Highway 12 and stop maintaining the large dunes that protect it. Withdrawing the road and dunes would allow sand to wash over the islands and rebuild them.
In his view, tourists could travel by ferry, like those that connect people to Ocracoke and Bald Head Islands today. The idea doesn't appeal to locals, who say ferries couldn't keep pace with the number of visitors who want access to the islands. She's in favor of shoring up narrowing beaches with sand delivered from elsewhere.
Edwards, the mayor of Nags Head, says nourishment protected the tourism industry and buffered the town during Hurricane Sandy. According to a survey conducted in June by the contracting company that completed the Nags Head project, 97 percent of the sand from the project still remains.
But Nags Head may be an outlier; Riggs says other beach nourishment projects in the state lasted only two or three years. Beach nourishment isn't a long-term solution, says Orbach, the marine policy specialist, because there isn't enough sand to go around for all of the communities on the Atlantic Coast that will want it in the next 50 years. We will, in fact, retreat from most coastal places when the sea level gets more than one or two meters above where it is now.
It is not necessarily dangerous to live on the coast, however it is not the best idea. Beach erosion is unpredictable, and can lead to dangers such as flooding, property damage, and property loss. If you do decide to live near the coast, however, be sure to choose a location far enough away from the shorline to provide a "buffer zone" between your property and the ocean.
North Carolina's beloved coast is a victim of a natural process called coastal erosion. Beaches are always shifting, building, and eroding away. North Carolina's coast is simply following normal trends in nature. Login to rate this Glog. But, he said, they are also working on less visible projects. They are looking for a contractor now to help make a plan for making the sound side of the island more resilient. Holly White, the principal planner for the Town of Nags Head, said community input was a driver in planning for sea-level rise and climate change.
How do you see natural hazards affecting the town? The town worked for years to come up with a set of plans and rules to help deal with sea level rise, including raising homes, rebuilding the beach and dealing with heavy rains that can flood streets.
Extreme weather is not new for the Outer Banks, Zehner said. But they are seeing more erosion on the beaches and more frequent and severe storms, he said. The average annual rate of sea-level rise varies along the coast. In Oregon Inlet, not far from Nags Head, the rate is about 5.
In Southport, in the southeast corner of the state, the rate is more like 2 millimeters a year. Scientists generally agree those rates will increase in the coming decades.
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