“Sea levels could rise faster along the U.S. East Coast than in any other densely populated part of the world,” warns an article in the June 8 Washington Post. The warning sounds silly, after all, it’s water, and water in the tub is never “uneven”—but several recent scientific findings conclude that not only will sea level rise (SLR) vary from place to place, but that the US East Coast, in comparison with all other coastlines in the world, is likely to experience the highest SLR in coming years. Of course, the Eastern seaboard faces multiple other environmental threats. Five Mid-Atlantic governors have signed an agreement to work collaboratively to “advance a regional approach” to coastal problem-solving that includes rising seas, and to hold a stakeholder summit in late 2009. And a Bush-era gag order on EPA sea level rise expert Jim Titus has apparently been lifted.
post by Anne Polansky (comments may be sent to [redacted]
(Revised July 2, 2009, to include additional information about unpublished maps related to U.S. coastal lands and sea level rise.)
The old adage, “Nothing is certain but death and taxes” now has a third certainty we can bank on: sea level rise (SLR). A triple whammy promises to demand our attention: 1) thermal expansion, 2) arctic ice melt, and 3) densely populated coastlines with high-value real estate and invaluable natural resources, is coalescing to spell out serious trouble ahead for millions of Atlantic coast dwellers and the economy that supports them, unless we take decisive action to prepare and ultimately defend ourselves against consequences that range from the unpleasant and inconvenient, to the destructive and devastating.
Moreover, scientists are discovering, SLR will not occur uniformly around the globe. Ocean water doesn’t spread out evenly, but rather varies up to several feet (note, the rest of the world talks about meters and centimeters) from one location to another, depending on various factors such as ocean circulation and compression at lower depths. The U.S. East Coast is expected to bear the brunt of this non-uniformity.
The Washington Post covered this issue nicely on June 8. We were pleased to see that a veteran expert on sea level rise at the US Environmental Protection Agency, Jim Titus, is referenced twice in the article:
In the Washington region, Environmental Protection Agency official James G. Titus said, Hains Point, along the Southwest Waterfront, and K Street NW in Georgetown might have to be elevated. Sections of the waterfront Fells Point neighborhood in Baltimore might also need to be jacked up.
And, Titus said, rural areas along the water might have to be abandoned. On Maryland’s Eastern Shore, for instance, rising seas could eat up large sections of marshy Dorchester County.
For a time under the Bush administration, Titus was prohibited from talking with reporters about his work at the EPA or his expert knowledge of sea level rise and its implications. (See our coverage from June 2006):
We hope to be seeing him consulted and quoted more often in the mainstream media and elsewhere, and commend the new EPA leadership if this is a sign of a more open communication policy. We also hope that EPA publishes his studies suppressed during the Bush Administration.
Several key studies lay out the SLR threat and give it more definition than the latest IPCC findings in 2007:
• Under President Bush, the U.S. Climate Change Science Program produced a report (as one of a set of 21), “Coastal Sensitivity to Sea-Level Rise: A Focus on the Mid-Atlantic Region” produced jointly by the U.S. Environmental Protection Agency, the U.S. Geological Survey, and the National Oceanic and Atmospheric Administration. Jim Titus served as the coordinating lead author.
The report discusses the impacts of sea-level rise on the physical characteristics of the coast, on coastal communities, and the habitats that depend on them; examines multiple opportunities for governments and coastal communities to plan for and adapt to rising sea levels; and discusses institutional barriers that prevent them from doing so. The final version of this report excluded two sets of maps and data tables that had been included in earlier drafts:
? Maps from a 2008 EPA study showed lands potentially vulnerable to sea level rise. Public comment and a federal advisory committee report to then-Administrator Johnson criticized EPA for removing these maps from the report. EPA has also excluded the maps from its web site. (The maps are available on Jim Titus’ more sea level rise maps web site.)
? Maps from a 6-year study evaluating the likely response to sea level rise, showing lands likely to be protected and lands likely to be available for wetlands to migrate inland. The federal advisory committee reviewed the study and recommended to Administrator Johnson that it should be published, but the study is still unavailable.
• “State of the U.S. and Coastal Economies—2009” by the National Ocean Economic Program:
The results of the first independent report on the ocean and the U.S. economy released today by the National Ocean Economic Program (NOEP) during Capitol Hill Ocean Week, shows that in 2007, four in five Americans lived in coastal states, generating 83% of the nation’s economic output, and contributing $11.4 trillion to the national gross domestic product (GDP).
The report highlights the enormous overall value of the ocean and our nation’s coasts, and the critical role these areas play in America’s economic health and well-being. The report also shows that these areas, which have been hit hard by the recession, are also under considerable future risk due to the effects of climate change, ocean acidification, and sea-level rise.
Some Key findings:
• In 2007, four in five Americans lived in coastal states and generated 83% of the nation’s output. The thirty coastal states had 245.5 million people, employed 107.5 million people, and contributed $11.4 trillion to the national gross domestic product (GDP).
• More than three-quarters of U.S. growth between 1997 and 2007 was in coastal states, whether measured by population, employment, or GDP.
• Coastal tourism and recreation dominated employment in the ocean economy sectors with 1.7 million jobs or 75% of ocean economy employment; marine transportation had the second largest GDP, with $27.6 billion, 20% of the ocean economy.
• In 2008, the federal government spent $9.5 billion or .03% of the federal budget for civilian programs on oceans, coasts, and Great Lakes programs.
• Ocean and coastal economies are being affected now by the current economic recession, but the future will bring more significant environmental changes to the ocean and coasts, such as sea level rise, oxygen depletion, and ocean acidification, which are all driven by greenhouse gas emissions.
• Research at the National Center for Atmospheric Research (see May 27, 2009 press release, “Melting Greenland Ice Sheets May Threaten Northeast United States, Canada,” generated a technical paper published in Geophysical Research Letters titled “Transient Response of the MOC and Climate to Potential Melting of the Greenland Ice Sheet in the 21st Century” – a few excerpts from the press release:
“Melting of the Greenland ice sheet this century may drive more water than previously thought toward the already threatened coastlines of New York, Boston, Halifax, and other cities in the northeastern United States and Canada”
“[I]f Greenland’s ice melts at moderate to high rates, ocean circulation by 2100 may shift and cause sea levels off the northeast coast of North America to rise by about 12 to 20 inches (about 30 to 50 centimeters) more than in other coastal areas. The research builds on recent reports that have found that sea level rise associated with global warming could adversely affect North America, and its findings suggest that the situation is more threatening than previously believed.”
“The northeast coast of North America is especially vulnerable to the effects of Greenland ice melt because of the way the meridional overturning circulation acts like a conveyer belt transporting water through the Atlantic Ocean. The circulation carries warm Atlantic water from the tropics to the north, where it cools and descends to create a dense layer of cold water. As a result, sea level is currently about 28 inches (71 cm) lower in the North Atlantic than the North Pacific, which lacks such a dense layer.”
“If the melting of the Greenland Ice Sheet were to increase by 3 percent or 7 percent yearly, the additional fresh water could partially disrupt the northward conveyor belt. This would reduce the accumulation of deep, dense water. Instead, the deep water would be slightly warmer, expanding and elevating the surface across portions of the North Atlantic.”
Global warming raises the specter of melting glaciers and ice sheets at both ends of the globe. The West Antarctic Ice Sheet, roughly the size of Texas, extends over both land and water west of Antarctica’s Transantarctic mountains. Even partial melting of this vast ice sheet would cause a significant rise in sea level.
But that sea level rise would not happen uniformly around the globe, according to an article in Science magazine. The authors show that when physical and gravitational factors are applied to projections of sea level rise, the impact on coastal areas is dramatically worse in some parts of the world than predicted so far.
Science Daily covered the findings:
University of Toronto and Oregon State University geophysicists have shown that should the West Antarctic Ice Sheet collapse and melt in a warming world – as many scientists are concerned it will – it is the coastlines of North America and of nations in the southern Indian Ocean that will face the greatest threats from rising sea levels.
The catastrophic increase in sea level, already projected to average between 16 and 17 feet around the world, would be almost 21 feet in such places as Washington, D.C., scientists say, putting it largely underwater. Many coastal areas would be devastated. Much of Southern Florida would disappear, according to researchers at Oregon State University.
“There is widespread concern that the West Antarctic Ice Sheet may be prone to collapse, resulting in a rise in global sea levels,” says geophysicist Jerry X. Mitrovica, who, along with physics graduate student Natalya Gomez and Oregon State University geoscientist Peter Clark, are the authors of a new study to be published in the February 6 issue of the journal Science. “We’ve been able to calculate that not only will the rise in sea levels at most coastal sites be significantly higher than previously expected, but that the sea-level change will be highly variable around the globe,” adds Gomez….
“The typical estimate of the sea-level change is five metres, a value arrived at by taking the total volume of the West Antarctic Ice Sheet, converting it to water and spreading it evenly across the oceans, says Mitrovica. “However, this estimate is far too simplified because it ignores three significant effects:
* when an ice sheet melts, its gravitational pull on the ocean is reduced and water moves away from it. The net effect is that the sea level actually falls within 2,000 km of a melting ice sheet, and rises progressively further away from it. If the West Antarctic Ice Sheet collapses, sea level will fall close to the Antarctic and will rise much more than the expected estimate in the northern hemisphere because of this gravitational effect;
* the depression in the Antarctic bedrock that currently sits under the weight of the ice sheet will become filled with water if the ice sheet collapses. However, the size of this hole will shrink as the region rebounds after the ice disappears, pushing some of the water out into the ocean, and this effect will further contribute to the sea-level rise;
* the melting of the West Antarctic Ice Sheet will actually cause the Earth’s rotation axis to shift rather dramatically – approximately 500 metres from its present position if the entire ice sheet melts. This shift will move water from the southern Atlantic and Pacific oceans northward toward North America and into the southern Indian Ocean.
STATES RISE TO MEET THE CHALLENGE
Five Atlantic Coast state governors apparently got the wake-up call, and have formed a coalition that will be working over the next months to develop common solutions to common problems particular to coastal areas, and will gather late this year for a “stakeholder summit” to go over their findings and talk about next steps with affected communities.
Many of these states are already accustomed to collaborating to help “Save the Bay” (the Chesapeake Bay) but this is the first time these five states have agreed to work together on the many issues facing coastal managers, from the northern tip of Long Island (NY) to the barrier islands south of Virginia Beach, famous for their migratory birds.
(We’d be remiss not to point out that these states organized on their own, with no support, no prompting, no funding, no nothing from the federal government (that we know of!)… a disconnect and dysfunction we argue should be corrected: numerous federal resources in multiple agencies have the tools and resources to assist these states in this ambitious, bold, and commendable gesture.)
The agreement is called the Mid-Atlantic Council on the Ocean (or MARCO)
The five participating states and their respective Governors are:
New York: Governor David Paterson
New Jersey: Governor Jon S. Corzine
Delaware: Governor Jack A. Markell
Maryland: Governor Martin A. O’Malley
Virginia: Governor Timothy Kaine
The four-page MARCO Agreement lays out the threats to Mid-Atlantic coastal areas and lists guiding principles, priorities, and shared actions they promise to take together going forward. Of the four priorities, this one addresses the SLR issue most directly:
>>Prepare the region’s coastal communities for the impacts of climate change on coastal and ocean resources. Climate change and its associated impacts threaten to alter indelibly the Mid-Atlantic region and its resources. Increased coastal hazards, such as flooding and erosion, will threaten existing infrastructure and public health and safety. The widespread nature of this problem also will challenge our efforts to manage human activities across the region. (emphasis added)
We are pleased to see the term “prepare”—and prefer this to the more common rhetoric around the word “adaptation,” which we believe implies that we will be able to adapt to all climate change impacts—a scenario that we don’t see as very likely.
We will be monitoring and reporting periodically on the activities of MARCO and will look forward to attending the “stakeholder summit” later this year.
Associated Press (June 4)
Baltimore Sun (June 4)