Sea-Level Rise: The onrushing train
By CATHERINE KOZAK
Coastal Review Online
at least a decade, numerous North Carolina scientists have been warning
with increasing stridency about the state’s vulnerability to impending
sea-level rise, but policymakers have yet to take heed.
reports released this month by a group of independent researchers,
however, have only reinforced the dire predictions about the effects of
a rising Atlantic on the state’s coast.
“Our hope is, really, to provide useful information and help people prepare,” said Ben Strauss, an author of “Surging Seas,” and director of the program on sea-level rise with Climate Central,
a nonprofit journalism and research organization based in Princeton,
N.J. “The problem is very real. In the scientific community, the only
real debate is how fast and how much.”
the report said, has the third-highest amount of land area in the
nation that would be inundated by one meter (39 inches) or less of
water. It ranks sixth in the number of houses affected and eighth in
the population affected.
Of the counties in the state with the largest total population exposed to the risk, Dare County ranks No. 1.
is hardly a surprise to Stan Riggs, an East Carolina University coastal
geologist who has been studying the Outer Banks since the 1970s.
“The bottom line with sea-level rise, this has been going on for 18,000 years now,” said Riggs, whose book The Battle for North Carolina’s Coast, was also released recently.
he has told anyone who will listen, storm damage on the Outer Banks
that leaves roads torn up and houses stranded in the water is only
going to increase.
in the ocean because sea level is still rising,” Riggs said. “This is
fact. There’s a train coming down the tracks and it’s getting closer
According to “Surging Seas” and a related report
by the Environmental Research Letters, the best estimate for the
average level of sea rise by 2030 on the Atlantic coast is six inches;
by 2050, it’s 13 inches.
The Rising Sea
North Carolina, there is a one in six chance that combined sea-level
rise, storm surge and tide will exceed three feet by 2020, flooding 3.5
percent of the state’s acreage and 0.9 percent of the state’s
contrast, the chances are equal that that same amount of water would
flood 65.8 percent of Dare County land, impacting 23.1 percent of the
homes. In Nags Head, it would amount to 16 percent of the land and 13.7
percent of the homes; in Kitty Hawk, it would be 53.9 percent and 21.7
percent, respectively; in Hatteras, 71.6 percent and 74.6 percent; and
in Ocracoke, 45.4 percent and 80.8 percent.
Stewart, a biologist with Pea Island National Wildlife Refuge and
Alligator River National Wildlife Refuge, said he has already seen the
effects of rising seas in Alligator River, which is about two feet
above sea level. Saltwater intrusion has been gradually killing off
trees, he said, and canals running through refuge lands on the Dare
County mainland allow saltwater to “jet” farther into the interior
system. Over the years, he has seen swaths of land transitioning
from pond pine pocosin to salt marsh.
said that the refuge is working with The Nature Conservancy on ways to
adapt and manage for sea-level rise in Alligator River, including
planting salt-tolerant trees.
Pea Island on the north end of Hatteras Island, Stewart said he has
observed “tremendous” beach erosion, even on the sound side. Left to
nature, the island would be migrating west and widening the sound
beach. But maintenance of Highway 12 and dunes along the ocean side
prevents that process.
the island is getting narrower and narrower and will continue to do
that,” Stewart said. “Our game plan is to manage Pea Island pretty much
as we are now.”
it is clear that one day the ocean will blow out the dikes of each of
the refuge’s three bird impoundments, he said. When that happens,
whatever is left will be managed as sand flats and marsh.
Irene in August tore an inlet through the refuge and breached Highway
12 at the so-called “S-Curves” on the south end of the refuge. The
state Department of Transportation has since restored the road and is
working on long-term solutions.
Although Stewart won’t venture to guess what rate seas will rise, he doesn’t question the validity of the science.
accept it,” he said. “Only time is going to tell who’s right and who’s
wrong about sea-level rise. I want to err on the side of
Riggs, on the other hand, expresses no doubt that N.C 12 does not have much of a future on Pea Island.
if you hold Pea Island, the state of North Carolina does not have the
money to hold those weak spots,” he said. “No matter what you do there,
you’re going to have problems.”
it comes to fighting geology and the rising ocean, Riggs is confident
that sooner or later, the Outer Banks will throw in the towel on
Highway12. In fact, if another storm like Irene came right now,
he said, “we’d already be there.”
Riggs believes the state should be proactive and plan innovative
transportation systems, including high-speed ferries that would
preserve the coastal economy.
are the most spectacular waters in the world,” he said. “People would
come from all over the world to see this place. We have to figure out
ways to make that happen.”
An Alternate Vision
if Highway 12 was under water on Pea Island and other weak spots on
Hatteras Island --- areas he called “wimpy” barrier island --- Riggs
said the villages are less vulnerable because they’re built on higher,
more stable ground.
the road was allowed to go away, he predicted, the barrier islands
would naturally rebuild --- by moving like “a tank tread” --- and the
pollutants in Pamlico Sound would be flushed. The healthy nutrient
balance would be restored, the water would become saltier, habitats for
threatened species would be renewed and fishing would improve. In
essence, the equilibrium of the natural system would be restored.
if the system was left alone, the Hatteras flats on the soundside, old
flood tide deltas, would help the islands to regenerate.
“I like to think of them as the barrier island retirement system,” Riggs said.
Outer Banks has the potential to be like Core Banks, “a very happy set
of barrier islands,” that have been allowed to grow
Riggs wrote in his book, the barrier islands could become "eight
Ocracoke-style destination villages, situated like a string of pearls
on a vast network of inlet and shoal environments."
said that he has received very positive feedback from the public during
his recent book tours, but he has seldom heard from any
“It’s like they don’t want to know too much,” he said. “The politicians are thinking short term.”
sea-level rise report submitted recently by a state-appointed panel of
scientists to the N.C. Coastal Resources Commission has been pulled to
allow time for the division to respond to critiques of the report, said
Tancred Miller, the coastal policy analyst for the state Division of
Much of the feedback on the report, which had projected sea-level rise between 39 to 54 inches by 2100, Miller said, came from NC-20, a lobbying group for homebuilders and some coastal counties. The division has posted a much watered-down draft of the report that reflects changes requested by the lobbying group.
said that North Carolina has not yet established any official policy to
address climate change or sea-level rise. But, he said, it is a
priority with the commission, which had asked for the sea-level rise
a place to start,” he said, “just to get an understanding if there is a
problem that we need to understand and prepare to react
Other states, including Rhode Island, Maryland, Delaware, Florida,
California and New York, he said, have some sort of sea-level policy or
“I think that there are a lot of states that we can look to that are taking it seriously,” Miller said.
story is provided courtesy of Coastal Review Online, the coastal news
and features service of the N.C. Coastal Federation. You can read other
stories about the N.C. coast at www.nccoast.org.)