Summit County Citizens Voice

A NASA satellite image shows the how susceptible Cape Hatteras National Seashore is to rising sea levels.

Rising sea levels threatens to inundate low-lying barrier islands

By Summit Voice

SUMMIT COUNTY — With parts of the U.S. Atlantic coastline already seeing sea levels rising faster than global averages, several national seashores that host millions of visitors annually are at risk of losing beaches or even being completely swamped by the sea.

Fire Island National Seashore in New York, Assateague Island National Seashore in Maryland and Virginia, as well as North Carolina’s Cape Hatteras and Cape Lookout national seashores, are all for the most part, less than 1 meter above sea level, thus facing inundation, according to a new report from the Rocky Mountain Climate Organization and the Natural Resources Defense Council.

Along with the direct impacts to the national seashores, the loss of dune ecosystems and other shoreline features would expose shorelines along the mainland to the often devastating effects  of winds and surging flood waters from hurricanes, nor’easters, and other coastal storms. Get the full report here.

Parts of Cape Cod National Seashore and Cumberland Island National Seashore in Georgia are also at risk, according to the report, which includes the first set of maps detailing the portions of Atlantic national seashores that are low lying enough to be at real risk of being submerged by rising sea levels.

“Major parts of each of these seashores, including most lands in five of them, could be lost forever under a higher ocean if we do not stop disrupting the climate,” said report author Stephen Saunders.

“Climate change is the greatest threat ever to our national park systems. These seashores certainly are among the most vulnerable areas. Human alteration of the climate threatens to undercut our national promise that these special places will be preserved unimpaired for the enjoyment of my children and future generations,” said Saunders, president and founder of the Rocky Mountain Climate Organization.

Other climate change impacts outlined in the report include the loss of bridges and roads that provide access to the seashores, breakup of barrier islands into smaller segments, extensive beach erosion, and loss of wildlife.

Many climate models suggest that sea levels could rise by at least 1 meter during this century.

“Massive and preventable damage to national seashores is too high a price to pay for failing to act on climate change. This report makes clear that if we don’t cut the amount of heat‐trapping pollution we spew into the air, these special places that Americans love will never be the same,” said the NRCD’s Theo Spencer.

“We’ve made some progress, including national standards to make cars cleaner and more efficient, and new health protections from power plant pollution. But more must be done. For starters, we need to allow the Environmental Protection Agency to continue doing its job controlling heat‐trapping pollution that harms our health and the places we love,” Spencer said.

Rising temperatures could discourage visitation to the national seashores. Under a medium-to-emissions scenario, temperatures at Cumberland Island NS could rise 6.3 degrees, matching the current summer climate in desert‐ bound White Sands National Monument in New Mexico.

The seven national seashores draw a total of about 11 million visitors a year, contributing to the economy of seven states by generating more than half a billion dollars in spending and supporting nearly 8,000 jobs.

The report’s findings could help land and resource managers plan for the future, according to S. Jeffress Williams, a retired scientist from the U.S. Geological Survey.

“Science is compelling that climate is changing, becoming warmer and much more variable. Many impacts are already affecting Atlantic national seashores and will do so for decades into the future,” Williams said during a teleconference announcing the report. “

This new assessment is important for planning for these changes by documenting effects such as sea‐level rise and warming on both the natural resources in the parks and also the public who visit the parks and value what the parks offer,” he said.

Key findings from the report include:

• Cape Cod National Seashore, the most visited of the Atlantic national seashores, could see summer temperatures rise 6.1 degrees by the end of this century, making it as hot in summers as Cape May, New Jersey, today. Cape Cod NS has higher, more stable lands than the other seashores, but heavily visited beaches near Chatham and Provincetown could be submerged by a higher sea.
• Fire Island National Seashore, located only 40 miles from Manhattan, has most of its land one meter or less above sea level, primarily on the inland side of the island. Based on projected wave height, susceptibility to erosion, and tidal range, Fire Island has a high vulnerability to shoreline change from sea‐level rise.
• Assateague Island National Seashore, a barrier island stretching from the Ocean City Inlet in Maryland south into Virginia, has most of its land one meter or less above sea level. The seashore also has experienced the highest rate of sea‐ level rise of all the Atlantic seashores. Assasteague’s summers could get 6.2 degrees hotter, equal to those of Key West, FL, today. Assateague Island NS is rated as having an almost entirely very high overall vulnerability to sea level rise based on wave heights, susceptibility to erosion, among other factors.
• Cape Hatteras National Seashore, America’s first national seashore, covers much of North Carolina’s Outer Banks. Most of the seashore’s land is less than one meter above sea level. By century’s end, the summer temperatures in Cape Hatteras could rise 5.4 degrees, matching those of Galveston, Texas today. Cape Hatteras is rated as having an almost entirely very high overall vulnerability to sea level rise. Cape Hatteras has experienced more hurricanes than any of the other Atlantic national seashores, with 49 hurricanes passing within 65 miles of the seashore since 1842.
• Cape Lookout National Seashore, on the Outer Banks just south of Cape Hatteras , has most of its land less than one meter above sea level. Near the end of the century, summer temperatures at Cape Lookout could rise 5.6 degrees to match summertime temperatures today in Ft. Myers, FL. Cape Lookout is rated as having an almost entirely very high overall vulnerability to sea level rise, compared to other locations on the U.S. Atlantic Coast. Cape Lookout also has a history of very high hurricane frequency, with 43 hurricanes passing within 65 miles of the cape since 1842.
• Cumberland Island NS covers most of Georgia’s largest and southernmost island in the Sea Islands. Cumberland Island is primarily a wide, stable island, making it less vulnerable to shoreline change than most of the other seashores, but some beaches and extensive areas of salt marsh are less than one meter above sea level.
• Canaveral National Seashore, contiguous to the Kennedy Space Center, has 24 miles of undeveloped beaches, the longest such stretch on Florida’s Atlantic Coast. Most of the seashore lands are less than one meter above sea level. The seashore ranks entirely of very high vulnerability based on wave heights, susceptibility to erosion, and other factors. Canaveral NS has two particular risks because of the nature of its
  barrier island: its 24‐mile barrier island is such a thin ribbon of sand that in some places it is no more than 100 yards wide, with obvious risks of segmentation; and unlike many barrier islands with multiple rows of dunes affording additional protection from storm surges and overwash, Canaveral has only a single dune row.

The report also outlines the steps needed to avoid further climate disruption to national seashore areas, including:

• Establishing comprehensive mandatory limits on carbon pollution to reduce emissions by at least 20 percent below current levels by 2020 and 80 percent by 2050;
• Protecting the current Clean Air Act authority of the U.S. Environmental Protection Agency (EPA), allowing EPA to do its job of protecting American’s health by cutting pollution;
• Overcoming barriers to investment in energy efficiency to lower emission‐reduction costs, starting now;
• Accelerating the development and deployment of emerging technologies to lower long‐term emission reduction costs; and,
• Actions by the National Park Service to identify and protect threatened seashore resources and to reduce its own emissions of heat‐trapping pollution, combined with visitor education exhibits and programs on climate change threats and examples of emission reduction efforts. With 279 million visits in 2011, the national park system can play a unique role in presenting climate change information to people.

Filed under: climate and weather, Environment, global warming, national parks, public lands Tagged: | Assateague Island National Seashore, Cape Cod National Seashore, climate change, Cumberland Island National Seashore, global warming, national seashores, Outer Banks, rising sea level