Tag Archives: Sea Level Rise

Global Warming Mapped, NASA

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2000-2009

By Michael Carlowicz, Earth Observatory, NASA

The world is getting warmer. Whether the cause is human activity or natural variability, thermometer readings all around the world have risen steadily since the beginning of the Industrial Revolution.

According to an ongoing temperature analysis conducted by scientists at NASA’s Goddard Institute for Space Studies (GISS), the average global temperature on Earth has increased by about 0.8°Celsius (1.4°Fahrenheit) since 1880. Two-thirds of the warming has occurred since 1975, at a rate of roughly 0.15-0.20°C per decade.

The maps above and below show temperature anomalies, or changes, for 2000-2009 and 1970-1979.

1970-1979
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NASA images by Robert Simmon, based on data from the Goddard Institute for Space Studies.

The maps do not depict absolute temperature, but how much warmer or colder a region is compared to the norm for that same region from 1951-1980.

That period was chosen largely because the U.S. National Weather Service uses a three-decade period to define “normal” or average temperature. The GISS temperature analysis effort began around 1980, so the most recent 30 years were 1951-1980. It is also a period when many of today’s adults grew up, so it is a common reference that many people can remember.

To conduct its analysis, GISS uses publicly available data from 6,300 meteorological stations around the world; ship-based and satellite observations of sea surface temperature; and Antarctic research station measurements. These three data sets are loaded into a computer analysis program—available for public download from the GISS web site—that calculates trends in temperature anomalies relative to the average temperature for the same month during 1951-1980.

The objective, according to GISS scientists, is to provide an estimate of temperature change that can be compared with predictions of global climate change in response to atmospheric carbon dioxide, aerosols, and changes in solar activity.

The temperatures we experience locally and in short periods can fluctuate significantly due to predictable cyclical events (night and day, summer and winter) and hard-to-predict wind and precipitation patterns. But the global temperature mainly depends on how much energy the planet receives from the Sun and how much it radiates back into space—quantities that change very little. The amount of energy emitted by the Earth depends significantly on the chemical composition of the atmosphere, particularly the amount of heat-trapping greenhouse gases.

Original Article

If an island state vanishes, is it still a nation?

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Rising sea, Maldives. Photo courtesy of: © Denis Delestrac

Excerpts;

Encroaching seas in the far Pacific are raising the salt level in the wells of the Marshall Islands. Waves threaten to cut one sliver of an island in two. “It’s getting worse,” says Kaminaga Kaminaga, the tiny nation’s climate change coordinator.

The rising ocean raises questions, too: What happens if the 61,000 Marshallese must abandon their low-lying atolls? Would they still be a nation? With a U.N. seat? With control of their old fisheries and their undersea minerals? Where would they live, and how would they make a living? Who, precisely, would they and their children become?

For years global negotiations to act on climate change have dragged on, with little to show. Parties to the 193-nation U.N. climate treaty are meeting again in this Caribbean resort, but no one expects decisive action to roll back the industrial, agricultural and transport emissions blamed for global warming, and consequently for swelling seas.

From 7,000 miles (11,000 kilometers) away, the people of the Marshalls, and of Kiribati, Tuvalu and other atoll nations beyond — can only wonder how many more years they’ll be able to cope.

“People who built their homes close to shore, all they can do is get more rocks to rebuild the seawall in front day by day,” said Kaminaga, who is in Cancun with the Marshallese delegation to the U.N. talks.

The Marshallese government is looking beyond today, however, to those ultimate questions of nationhood, displacement and rights.

“We’re facing a set of issues unique in the history of the system of nation-states,” Dean Bialek, a New York-based adviser to the Republic of the Marshall Islands who is also in Cancun, told The Associated Press. “We’re confronting existential issues associated with climate impacts that are not adequately addressed in the international legal framework.”

The Marshallese government took a first step to confront these issues by asking for advice from the Center for Climate Change Law at New York’s Columbia University. The center’s director, Michael B. Gerrard, in turn has asked legal scholars worldwide to assemble at Columbia next May to begin to piece together answers.

Nations have faded into history through secession, recently with the breakup of the former Yugoslavia, for example, or through conquest or ceding their territory to other countries.

But “no country has ever physically disappeared, and it’s a real void in the law,” Gerrard said during an interview in New York.

The U.N. network of climate scientists projects that seas, expanding from heat and from the runoff of melting land ice, may rise by up to 1.94 feet (0.59 meters) by 2100, swamping much of the scarce land of coral atolls.

But the islands may become uninhabitable long before waves wash over them, because of the saline contamination of water supplies and ruining of crops, and because warming is expected to produce more threatening tropical storms.

“If a country like Tuvalu or Kiribati were to become uninhabitable, would the people be stateless? What’s their position in international law?” asked Australian legal scholar Jane McAdam. “The short answer is, it depends. It’s complicated.”

McAdam, of the University of New South Wales, has traveled in the atoll nations and studied the legal history.

As far as islanders keeping their citizenship and sovereignty if they abandon their homelands, she said by telephone from Sydney, “it’s unclear when a state would end because of climate change. It would come down to what the international community was prepared to tolerate,” that is, whether the U.N. General Assembly would move to take a seat away from a displaced people.

The 1951 global treaty on refugees, mandating that nations shelter those fleeing because of persecution, does not cover the looming situation of those displaced by climate change. Some advocate negotiating a new international pact obliging similar treatment for environmental refugees.

In the case of the Marshallese, the picture is murkier. Under a compact with Washington, citizens of the former U.S. trusteeship territory have the right to freely enter the U.S. for study or work, but their right to permanent residency must be clarified, government advisers say.

The islanders worry, too, about their long-term economic rights. The wide scattering of the Marshalls’ 29 atolls, 2,300 miles (3,700 kilometers) southwest of Hawaii, give them an exclusive economic zone of 800,000 square miles (2 million square kilometers) of ocean, an area the size of Mexico.

The tuna coursing through those waters are the Marshalls’ chief resource, exploited by selling licenses to foreign fishing fleets. “If their islands go underwater, what becomes of their fishing rights?” Gerrard asked. Potentially just as important: revenues from magnesium and other sea-floor minerals that geologists have been exploring in recent years.

While lawyers at next May’s New York conference begin to sort out the puzzle of disappeared nations, the Marshallese will grapple with the growing problems.

The “top priority,” Kaminaga said, is to save the isthmus linking the Marshalls’ Jaluit island to its airport, a link now swept by high tides.

Meantime, a lingering drought this year led islanders to tap deeper into their wells, finding salty water requiring them to deploy emergency desalination units. And “parts of the islands are eroding away,” Kaminaga said, as undermined lines of coconut palms topple into the sea.

This week in Cancun and in the months to come, the Marshalls’ representatives will seek international aid for climate adaptation. They envision such projects as a Jaluit causeway, replanting of protective vegetation on shorelines, and a 3-mile-long (5-kilometer-long) seawall protecting their capital, Majuro, from the Pacific’s rising tides.

Islanders’ hopes are fading, however, for quick, decisive action to slash global emissions and save their remote spits of land for the next century.

“If all these financial and diplomatic tools don’t work, I think some countries are looking at some kind of legal measures,” said Dessima Williams, Grenada’s U.N. ambassador and chair of a group of small island-nations. Those measures might include appeals to the International Court of Justice or other forums for compensation, a difficult route at best.

In the end, islanders wonder, too, what will happen to their culture, their history, their identity with a homeland, even to their ancestors, if they must leave.

“Cemeteries along the coastline are being eroded. Gravesites are falling into the sea,” Kaminaga said. “Even in death we’re affected.”

Original Article

55 Percent of Venice Under Acqua Alta, Italy

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Photograph: SAF – Coastal Care

Excerpts

In Venice, Italy people awoke to warning sirens as the “acqua alta,” or high water, reached the highest level yet this year, leaving 55 per cent of the city underwater. The first “acqua alta” or high water of the winter swamped Venice’s historic district Friday, including St. Mark’s Square in the heart of the city…

Read Full Article

National Geographic Article

NOVA, Sinking Venice

That sinking feeling

Cancun’s Beaches: Vanishing Sand and Wasted Money

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Cancun beach erosion. Photo source: ©© John M

Excerpts;

Cancun’s eroding white sand beaches are providing a note of urgency to the climate talks being held just south of this seaside resort famed for its postcard-perfect vistas.

Rising sea levels and a series of unusually powerful hurricanes have aggravated the folly of building a tourist destination atop shifting sand dunes on a narrow peninsula…

Read Full Article; USA Today (12-04-2010)

The Battles For The Beaches of Cancun; The Independent (05-08-2010)

Sand Trafficking: Elaborate Schemes,

Many Coastal Wetlands Likely to Disappear this Century

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Hatches Harbor salt marsh, Cape Cod. The Hatches Harbor salt marsh is a remnant of a larger salt marsh complex that existed at the time of the first European settlement. USGS. Photo source: ©© Lydia Mann

By The U.S. Department of the Interior, U.S. Geological Survey

Many coastal wetlands worldwide, including several on the U.S. Atlantic coast, may be more sensitive than previously thought to climate change and sea-level rise projections for the 21st century.

U.S. Geological Survey scientists made this conclusion from an international research modeling effort published today in the journal Geophysical Research Letters, a publication of the American Geophysical Union. Scientists identified conditions under which coastal wetlands could survive rising sea level.

Using a rapid sea-level rise scenario, most coastal wetlands worldwide will disappear near the end of the 21st century. In contrast, under the slow sea-level rise projection, wetlands with low sediment availability and low tidal ranges are vulnerable and may drown. However, in the slow sea-level rise projection, wetlands with higher sediment availability would be more likely to survive.

Several coastal marshes along the east coast of the United States, for example, have limited sediment supplies and are likely to disappear this century. Vulnerable east coast marshes include the Plum Island Estuary (the largest estuary in New England) and coastal wetlands in North Carolina’s Albemarle-Pamlico Sound (the second-largest estuary in the United States).

“Accurate information about the adaptability of coastal wetlands to accelerations in sea-level rise, such as that reported in this study, helps narrow the uncertainties associated with their disappearance,” said USGS scientist Glenn Guntenspergen, an author of this report. “This research is essential for allowing decision makers to best manage local tradeoffs between economic and conservation concerns.”

“Previous assessments of coastal wetland responses to sea-level rise have been constrained because they did not consider the ability of wetlands to naturally modify their physical environment for adaptation,” said USGS scientist Matt Kirwan, an author of this report. “Failure to incorporate the interactions of inundation, vegetation and sedimentation in wetlands limits the usefulness of past assessments.”

USGS scientists specifically identified the sediment levels and tidal ranges (difference between high and low tide) necessary for marshes to survive sea-level rise. As water floods a wetland and flows through its vegetation, sediment is carried from upstream and deposited on the wetland’s surface, allowing it to gain elevation. High tidal ranges allow for better sediment delivery, and the higher sediment concentrations in the water allow wetlands to build more elevation.

Coastal wetlands provide critical services such as absorbing energy from coastal storms, preserving shorelines, protecting human populations and infrastructure, supporting commercial seafood harvests, absorbing pollutants and serving as critical habitat for migratory bird populations. These resources and services will be threatened as sea-level rise inundates wetlands.

The rapid sea-level rise scenario used as the basis for this study is accredited to Stefan Rahmstorf at Potsdam University, one of the contributing authors of the Intergovernmental Panel on Climate Change Fourth Assessment Report. The slow sea-level rise projection is from the A1B scenario of the Intergovernmental Panel on Climate Change Fourth Assessment Report.

Original Article

Norfolk, Virginia, Tackles Rise in Sea

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Coastal erosion, Virginia. Photo source: ©© MizGingerSnaps

Excerpts;

In this section of the Larchmont neighborhood, built in a sharp “u” around a bay off the Lafayette River, residents pay close attention to the lunar calendar, much as other suburbanites might attend to the daily flow of commuter traffic…

Read Full Original, The New York Time

Explaining Norfolk’s Creeping Tides

The Last house of Sinking Chesapeake Bay Island

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Last House on Holland Island, Maryland. Captions and Photo source: ©© baldeaglebluff

Excerpts;

The story was strange enough to be a child’s fable: In an isolated section of the Chesapeake Bay, there was a two-story Victorian house that seemed to emerge directly from the water. And, scurrying around it, there was a retiree, trying to keep the house from falling in.

Finally, the man gave up. And last month, the house did, too. Raked by a storm, it cracked at the spine and collapsed into a one-story wreck.

The tale of the house and the man illustrates the Chesapeake’s problem with rising oceans and sinking land. It has already erased life on most of the bay’s islands and now is threatening to erase the islands themselves…

Read Full Article, The Washington Post

Cancún must be about more than climate change

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Playa Del Carmen, coastal erosion. Photo source: ©© Andrewarchy

Excerpts;

Twelve months ago I stood up in front of heads of state at the UN climate talks in Copenhagen and told them that they could not negotiate with the climate; they would have to negotiate with each other. And as leaders prepare to meet again in Cancún next week, I repeat my plea…

Read Full Original, Guardian UK

Bangladesh and Maldives: Sand Export Deal in Sight

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Rising sea, Maldives. Photo courtesy of: © Denis Delestrac

Excerpts;

The government is seriously assessing the potentials of exporting sand to the Maldives as an inter-minister meeting yesterday decided to invite sand importers of Maldives to Bangladesh.

An inter-ministerial meeting held at the land ministry decided to send the invitation through the foreign ministry. The government will step further on this regard after getting specifications of sand quality from them…

Read Full Article, Dredging Today