Thought this might interest those of you who live on planet earth. From
>NEWS FROM THE WORLDWATCH INSTITUTE
>Worldwatch News Brief 00-02
>FOR IMMEDIATE RELEASE
>March 6, 2000
>MELTING OF EARTH'S ICE COVER REACHES NEW HIGH
>by Lisa Mastny
>The Earth's ice cover is melting in more places and at higher rates than
>time since record keeping began. Reports from around the world compiled
>Worldwatch Institute (see attached data table) show that global ice melting
>accelerated during the 1990s-which was also the warmest decade on record.
>Scientists suspect that the enhanced melting is among the first observable
>of human-induced global warming, caused by the unprecedented release of carbon
>dioxide and other greenhouse gases over the past century. Glaciers and
>features are particularly sensitive to temperature shifts.
>The Earth's ice cover acts as a protective mirror, reflecting a large share of
>the sun's heat back into space and keeping the planet cool. Loss of the ice
>would not only affect the global climate, but would also raise sea levels and
>spark regional flooding, damaging property and endangering lives. Large-scale
>melting would also threaten key water supplies as well as alter the
>many of the world's plant and animal species.
>Some of the most dramatic reports come from the polar regions, which are
>faster than the planet as a whole and have lost large amounts of ice in recent
>decades. The Arctic sea ice, covering an area roughly the size of the United
>States, shrunk by an estimated 6 percent between 1978 and 1996, losing an
>average of 34,300 square kilometers-an area larger than the Netherlands-each
>The Arctic sea ice has also thinned dramatically since the 1960s and 70s.
>Between this period and the mid-1990s, the average thickness dropped from 3.1
>meters to 1.8 meters-a decline of nearly 40 percent in less than 30 years.
>The Arctic's Greenland Ice Sheet-the largest mass of land-based ice outside of
>Antarctica, with 8 percent of the world's ice-has thinned more than a
>year on average since 1993 along parts of its southern and eastern edges.
>The massive Antarctic ice cover, which averages 2.3 kilometers in
>represents some 91 percent of Earth's ice, is also melting. So far, most
>loss has occurred along the edges of the Antarctic Peninsula, on the ice
>that form when the land-based ice sheets flow into the ocean and begin to
>Within the past decade, three ice shelves have fully disintegrated: the
>the Larsen A, and the Prince Gustav. Two more, the Larsen B and the
>in full retreat and are expected to break up soon, having lost more than
>one-seventh of their combined 21,000 square kilometers since late 1998-a loss
>the size of Rhode Island. Icebergs as big as Delaware have also broken off
>Antarctica in recent years, posing threats to open-water shipping.
>Antarctica's vast land ice is also melting, although there is disagreement
>how quickly. One study estimates that the Western Antarctic Ice Sheet (WAIS),
>the smaller of the continent's two ice sheets, has retreated at an average
>of 122 meters a year for the past 7,500 years-and is in no imminent danger of
>collapse. But other studies suggest that the sheet may break more abruptly if
>melting accelerates. They point to signs of past collapse, as well as to
>fast-moving ice streams within the sheet that could speed ice melt, as
>of potential instability.
>Outside the poles, most ice melt has occurred in mountain and subpolar
>which have responded much more rapidly to temperature changes. As a whole, the
>world's glaciers are now shrinking faster than they are growing, and losses in
>1997-98 were "extreme," according to the World Glacier Monitoring Service.
>Scientists predict that up to a quarter of global mountain glacier mass could
>disappear by 2050, and up to one-half by 2100-leaving large patches only in
>Alaska, Patagonia, and the Himalayas. Within the next 35 years, the Himalayan
>glacial area alone is expected to shrink by one-fifth, to 100,000 square
>The disappearance of Earth's ice cover would significantly alter the global
>climate-though the net effects remain unknown. Ice, particularly polar ice,
>reflects large amounts of solar energy back into space, and helps keep the
>planet cool. When ice melts, however, this exposes land and water surfaces
>retain heat-leading to even more melt and creating a feedback loop that
>accelerates the overall warming process. But excessive ice melt in the Arctic
>could also have a cooling effect in parts of Europe and the eastern United
>States, as the influx of fresh water into the North Atlantic may disrupt ocean
>circulation patterns that enable the warm Gulf Stream to flow north.
>As mountain glaciers shrink, large regions that rely on glacial runoff for
>supply could experience severe shortages. The Quelccaya Ice Cap, the
>water source for Lima, Peru, is now retreating by some 30 meters a year-up
>only 3 meters a year before 1990-posing a threat to the city's 10 million
>residents. And in northern India, a region already facing severe water
>an estimated 500 million people depend on the tributaries of the glacier-fed
>Indus and Ganges rivers for irrigation and drinking water. But as the
>melt, these rivers are expected to initially swell and then fall to
>low levels, particularly in summer. (In 1999, the Indus reached record high
>levels because of glacial melt.)
>Rapid glacial melting can also cause serious flood damage, particularly in
>heavily populated regions such as the Himalayas. In Nepal, a glacial lake
>in 1985, sending a 15-meter wall of water rushing 90 kilometers down the
>mountains, drowning people and destroying houses. A second lake near the
>country's Imja Glacier has now grown to 50 hectares, and is predicted to burst
>within the next five years, with similar consequences.
>Large-scale ice melt would also raise sea levels and flood coastal areas,
>currently home to about half the world's people. Over the past century,
>in ice caps and mountain glaciers has contributed on average about
>the estimated 10-25 centimeter (4-10 inch) global sea level rise-with the rest
>caused by thermal expansion of the ocean as the Earth warmed. But ice melt's
>share in sea level rise is increasing, and will accelerate if the larger ice
>sheets crumble. Antarctica alone is home to 70 percent of the planet's fresh
>water, and collapse of the WAIS, an ice mass the size of Mexico, would
>levels by an estimated 6 meters-while melting of both Antarctic ice sheets
>raise them nearly 70 meters. (Loss of the Arctic sea ice or of the floating
>Antarctic ice shelves would have no effect on sea level because these already
>Wildlife is already suffering as a result of global ice melt-particularly
>poles, where marine mammals, seabirds, and other creatures depend on food
>at the ice edge. In northern Canada, reports of hunger and weight loss among
>polar bears have been correlated with changes in the ice cover. And in
>Antarctica, loss of the sea ice, together with rising air temperatures and
>increased precipitation, is altering the habitats as well as feeding and
>breeding patterns of penguins and seals.
>FOR MORE INFORMATION JOURNALISTS CAN CONTACT:
>Lisa Mastny, Staff Researcher (202) 452-1992, ext. 533; email@example.com
>Mary Caron, Press Director (202) 452-1992, ext. 527; firstname.lastname@example.org
>Also visit the Worldwatch website at www.worldwatch.org.
>To receive Worldwatch press advisories and advance releases by e-mail, send a
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>TABLE 1: SELECTED EXAMPLES OF ICE MELT AROUND THE WORLD
>Has shrunk by 6 percent since 1978, with a 14 percent loss of thicker,
>year-round ice. Has thinned by 40 percent in less than 30 years.
>Has thinned by more than a meter a year on its southern and eastern edges
>Has retreated nearly 13 kilometers since 1982. In 1999, retreat rate increased
>from 25 meters per day to 35 meters per day.
>Rocky Mtns., United States
>Since 1850, the number of glaciers has dropped from 150 to fewer than 50.
>Remaining glaciers could disappear completely in 30 years.
>Ice to the west of the Antarctic Peninsula decreased by some 20 percent
>1973 and 1993, and continues to decline.
>Pine Island Glacier
>Grounding line (where glacier hits ocean and floats) retreated 1.2
>year between 1992 and 1996. Ice thinned at a rate of 3.5 meters per year.
>Calved a 200 km2 iceberg in early 1998. Lost an additional 1,714 km2
>1998-1999 season, and 300 km2 so far during the 1999-2000 season.
>Terminus has retreated 3 kilometers since 1971, and main front has
>kilometers since 1982. Has thinned by up to 200 meters on average since the
>1971-82 period. Icebergs began to break off in 1991, accelerating the
>Meren, Carstenz, and Northwall Firn Glaciers
>Irian Jaya, Indonesia
>Rate of retreat increased to 45 meters a year in 1995, up from only 30
>year in 1936. Glacial area shrank by some 84 percent between 1936 and 1995.
>Meren Glacier is now close to disappearing altogether.
>Dokriani Bamak Glacier
>Retreated by 20 meters in 1998, compared with an average retreat of 16.5
>over the previous 5 years. Has retreated a total of 805 meters since 1990.
>Ulan Ula Mtns., China
>Glaciers have shrunk by some 60 percent since the early 1970s.
>Tien Shan Mountains
>Twenty-two percent of glacial ice volume has disappeared in the past 40
>Glacial volume has declined by 50 percent in the past century.
>Glacial area has shrunk by 35 to 40 percent and volume has declined by
>50 percent since 1850. Glaciers could be reduced to only a small fraction of
>their present mass within decades.
>Largest glacier has lost 92 percent of its mass since the late 1800s.
>Retreated by more than 150 meters between 1977 and 1990, compared with only
>35-45 meters between 1958 and 1977.
>Has retreated 60 meters a year on average over the last 60 years, and rate is
>Rate of retreat increased to 30 meters a year in the 1990s, up from only 3
>meters a year between the 1970s and 1990.
>Sources available upon request. For additional examples go to
One Kearny St., fourth floor
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