Scientists call the annual freezing (up to 7.2 million square miles) and the annual melting (up to 1.2 million square miles) of the Antarctic ocean the worlds biggest climate event. In September, when the ice begins to decay, an area the size of Maryland is lost each day. The formation of ice creates a colder saltier sea water which sinks to the bottom and drives global ocean currents. Without this salty layer on the bottom of the ocean, underwater ridges would trap the Atlantic deep water and cause the north Atlantic deep waters to remain trapped. This would cause significant climatic shifts which are discussed elsewhere. ("Breaking through a weather mystery", USA Today: Science, June 16, 1998, Page 50, by Jack Williams)
Newfoundland has been seeing a lot of icebergs. Two dozen floated to within view of St. Johns and are indicative of greater activity than usual this year. So far as of June 4, 263 icebergs have been sighted south of 48 degrees latitude, with the normal being 116 for the years 1961 through 1990. The U.S. Coast Guard International Ice Patrol has counted 4,200 icebergs, and in a normal year they count 4,800 by the end of September. Commander Stephen Sielbeck says he isnt sure why there are more icebergs this year, but he suspects El Nino has something to do with it. ("Banner year for icebergs has Newfoundland tourism booming", The Ottawa Citizen, June 5, 1998, Final Edition, News, Pg. A12, by Dave Mullington)
According to the Australian National Antarctic Research Expedition (ANARE), the amount of ice that is tied up in the Antarctic ice cap is 27 million cubic kilometers, which, if released, would cause a 65 meter (213 feet) rise in ocean levels. ("Fed: Global Warming will affect Antarctic ice sheet", AAP Newsfeed, May 27, 1998, Nationwide General News, Australian General News) The West Antarctic Ice Sheet, which may start breaking up as early as the next century, contains 3.8 million cubic kilometers of ice, about 14% of the Antarctic Ice. If this shelf melts, it would cause a 4 to 6 meter rise in sea level. Recent studies that have found high melting rates under the floating ice shelf of the West Antarctic Ice Sheet, as well as disappearance of many icebergs, make the amount of new ice formed less than the amount of ice melted--the sheet is shrinking. ("Climate: Global Warming Threatens Antarctica", Inter Press Services, May 27, 1998, by Danielle Knight)
Glaciers around the world are melting more rapidly than previously suspected, according to Dr. Mark Meier as reported at the American Geophysical Union meeting in Boston. "The rate of warming is unprecedented in the last 600 years, and the retreat of glaciers is probably unprecedented too, although we do not have the figures to prove it. ....But I am convinced there is a detectable human influence in the pattern of climate change we are seeing." Actual findings included the following reductions: Spain has lost 14 glaciers, half of the glacial ice is gone the Alps and the Caucasus in Russia, New Zealand has lost 26%, In Africa the largest glacier on Mount Kenya has lost 92% of its mass in the past 100 years while Kilimanjaro glaciers had receded by 73%, Tien Shan Mountains in China had lost 22% of their ice, and Montanas Glacier National Park will have no glaciers left in a century. ("Glaciers Retreat", AAP Newsfeed, May 26, 1998, Nationwide General News, Overseas News, by John von Radowitz)
The Surface Heat Budget of the Arctic Ocean (SHEBA) has found that the ice pack is thinning. The layer of fresh water under the icepack produced by the natural cycle of freezing and melting in the arctic is thicker. The ice is much thinner than scientist expected to find when the ship arrived in September. Said Igor Melnikov of the expedition, "During the icebreaker transit into the prospective SHEBA site, we were struck by the lack of thick ice. Where we expected ice from 2-3 meters we were hard pressed to find ice 1. 5 meters thick." The first samples of ocean temperature and salinity showed the upper ocean less salty and warmer than expected, likely signs of excessive melting. ("Science on Ice, Lab cracks mysteries of the Arctic", Anchorage Daily News, April 19, 1998, Final Edition, Nation, pg. 1A)
A large section of the Antarctic ice shelf, including an iceberg three miles by 25 miles has broken away from Larsen B shelf. The iceberg appears largely gone in a February 26 satellite pass image, and one on March 23 has confirmed that a large portion of the shelf had vanished. Stability of the shelf was already in doubt in February. Ted Scambos of the National Snow and Ice Data Center in Boulder, Colorado said, "This may be the beginning of the end for the Larsen ice shelf." Larsen B is bigger than all the previous ice that has been lost from the shelves in the past 20 years, but still accounts for only 1% of the ice shelves in Antarctica. About 2 thirds of the shelf is now threatening to break apart. ("Antarctic Ice Shelf on the Rocks", Press Association Newsfile, April 17, 1998, Home News, by John Von Radowitz)
Since 1979, Greenland has warmed by 2. 5 degrees C (4. 5 F), and the expected result is apparent in recent satellite images using beamed microwave pulses at the ice. Ice reflects the beam differently if it is in a melting zone or a dry snow, where the snow never melts. The image comparison shows that greater and greater areas of Greenland melt in the summer. ("Greenland is melting: warming temperature in Greenland since 1979", Walt Disney Company, Discover, April 15, 1998, IAC-ACC-NO: 20406315, No 4, Vol 19, pg. 14, ISSN: 0274-7529)
Scientists at Tundra Research Institute and Lanzhou Glacier have found that the glaciers in Mount Qomolangma area near Lanzhou, China have been shrinking over the last three decades. Compared to 1966 data the largest glacier in the area has shrunk significantly. About 8 of 19 glaciers in the area are in retreat. ("Mount Qomolangma Glaciers Shrinking", Xinhau News Agency, April 12, 1998, item #0412037)
Glaciologist Mindy Brugman of the Columbia Mountains Institute of Applied Ecology believes more and more of the Columbia Icefield is melting. "Were in a change that has not happened for a very long time and it doesnt seem to be turning around. More and more of the darker ice is being exposed and melting faster and faster and the glaciers are getting smaller." Since the late 1800s, glaciers in the field have lost 40-60 percent of their volume. The rate of loss has accelerated in the last 10-20 years. (The Vancouver Sun, April 8, 1998, Final Edition, News, Page B2, by Kevin Griffin, from Pacific Press Ltd)
Seven ice shelves in the last 25 years have broken up I Antarctica, but the Larsen B shelf is so far the biggest and the most southerly. "What you are seeing is one of many small pieces of information that are confirming that the whole planet is warming up. Theres been a great deal of calving in Antarctic glaciers. There is the retreat of mountain glaciers world wide and the increasing magnitude of El Nino events. All these are what I call contributory confirming pieces of evidence." says Kirk Dawson, executive director of the British Columbia-base Canadian Institute for Climate Studies. Andrew Weaver of University of Victoria, says "In terms of sea level rise, the collapse of Larsen B will have zero effect. The problem is that the floating ice shelves are like a wedge thats holding back the ice sheets on land." There is some evidence that the western Antarctica ice sheet could slip off into the ocean, and that would raise sea level by about 6 meters (19.7 feet) . Even if all human greenhouse gas emissions were stopped today, the inertia of the system has us committed to a 18. 5 cm (7. 2 inch) rise in sea levels over the next century. If the Antarctic ice cap completely melted, sea levels would rise by 66 meters (216 feet). Melting of ice, or standing water on ice both increase the absorption of sunlight (reduce reflectance) and increase the melting rate of the ice. This "positive feedback loop" is one of many for climate change that may make the process of global warming up go faster. ("Antarctica-Consequences of Change.... ", the Vancouver Sun, March 14, 1998, Final Edition, Satrev, pg. C6, by Stephen Hume, Pacific Press ltd)
The ice covering the Niagara River will be taken out March 2--the earliest removal date in its 33-year history. Its also the first time Lake Erie has remained unfrozen, all winter. ("Niagara river ice boom to make its earliest exit ever", The Buffalo News, February 28, 1998, Local, pg. 15B)
The ice covering Lake Mendota in Madison, Wisconsin, went out on a record-breaking February 27. This bests the previous record holder set in 1983, the last severe El Nino year. The Merrimac Ferry will resume operation in its Wisconsin River crossing on March 3, the earliest start in 60 years.
("Lake thaw sets record; Whats next? ", Capital Times-Madison Wisconsin, February 28, 1998, Local/State, pg. 2A)
Patches of grass have started to appear in Antarctica. Pete Convee, a biologist, examined a tiny tuft of grass on a rocky shoreline. Only a few years ago, this ground would have been frozen and covered in snow. But with rising temperatures, grasses and flowers are colonizing the area. Experts have recorded more rainfall, less lying snow, and a tenfold increase in the number of flowering plants there. British geologist Mike Thompson said he was "utterly amazed to see the dramatic and recent changes at Larsen B. ... In 25 years of Antarctic field work, I have never seen anything like it." Observers have been astonished by the size of some of the sheets of ice that have broken away. John Turner of the British Antarctic Survey said, "They dont look like icebergs. You cant grasp the size of them when you approach them from a ship--they extend as far as the eye can see." It is believed that ice sheets break up because melted water percolates through weak spots in the ice, transferring heat deep into the frozen shelf. Larsen B is a 7,500 square mile shelf, and is the furthest southern ice shelf that has been affected by the melting. Scientist say that the shelf is critically unstable and may collapse within the next two years. ("Chilling warning on global warming", the Scotsman, January 30, 1998, pg. 26) (NPR Morning Edition, NPR 10:00 am ET, January 30, 1998, transcript #98013004-210)
According to Dr. David Vaughan, in glaciological survey, the Antarctic Larsen Shelf B, currently the size of Britain, is unlikely to survive long into the next century. In the last two years more ice has broken off than in the last 50 years. Although these chunks of ice are very large in size, they represent a very, very, small part of the ice in Antarctica, and even if melting is occurring, it will be several generation hence for any big effects to occur. ("Scientist pours cold water on ice floe danger", The Evening Standard-London, January 29, 1998, pg. 14, Associated Newspapers, ltd.)
Mean annual temperatures a meter below the surface have risen by more than 1 degree C in the past decade in this far northern U.S. state, according to New Scientist, October 9th, edition reported in the Vancouver Sun. Lower lake levels, drought, forest fires, and some 2,000 landslides caused by melting permafrost in Canada's north are the result of global warming says a recent Northwest Territories report. "The greatest thaw since the glacial epoch provokes special concern among researchers. For instance, the average temperature in the greater part of Siberia was by 3-5 degrees C higher over the past few years than at the start of the century. ("Russia pays greater attention to ecology than in the past", TASS, September 30, 1997) In parts of Alaska, warming has increased tree growth, reduced precipitation, or increased winds and insect pests. Tree ring studies show no comparable period of warming in a 400-year history. (New Scientist This Week, October 11, 1997, page 4) ("Polar temperatures at 400-year high", The Christian Science Monitor, November 14, 1997, page 1 referring to Science article.) Plants give off carbon dioxide when they decay. The melting of the permafrost exposes organic matter to oxygen and also promotes the release of methane.
Scientifically, this effect is known as a positive feedback loop. It means that warming is going to enhance to warming. Studies suggest that the carbon dioxide stored in the permafrost could raise atmospheric CO2 by 50%. ("Melting tundra", NPR, 8 PM ET, All things considered, January 9, 1998, transcript 98010907-212, by David Baron and Jacki Lyden) "We found no evidence of high rates of carbon accumulation, possibly associated with nitrogen, elevated CO2, or climatic warming as has been suggested is occurring in the boreal zone on the basis of analyses of atmospheric CO2." ("Sensitivity of boreal forest carbon balance to soil thaw", American Association for the Advancement of Science, Science Journal, January 9, 1998, No. 5348, Vol. 279, pg. 214, ISSN: 0036-8075, by M.L. Goulden)
Continuous data from the 1930s in Wisconsin show a significant change in Pond Thaw data. Ponds that historically became ice-free in late April to early May, are now becoming ice-free in March (Global Change Research Program - Speaker's Series) Limnologist Dick Lathrop of University of Wisconsin, Madison has been studying Lake Mendotas freeze/thaw record. He notes no effect on freeze date which varies from November 23 to January 30, but he did find spring thaws are getting earlier. ("Interest is heating up in Lake Mendota freeze pool", Wisconsin State Journal, December 19, 1997, Local Wisconsin, page 1C)
The Broggi Glacier, Perus highest snowcap, slowly melted during the past 100 years, according to Benjamin Morales Arnao of the Andean Institute of Glaciology. It has receded 766 meter since the turn of the century. ("Melting Glacier", The Gazette, Montreal, Science, Earth Matters, Earthweek, December 17, 1997, page J10)
Somewhere below the surface of the western Arctic Ocean, a layer of warm water has been expanding and rising. No one is sure where its exact boundaries are, but one thing is certain. If the plume reaches beneath the polar ice cap, it could rapidly melt the cap. Wayne Grady has a new book out that describes this entirely new phenomenon. The Arctic Ocean is warming up from below. On a massive scale the Arctic Ocean can be envisioned as a giant double kitchen sink, with a range of undersea mountains, the Lomonosov Range being represented by the divider between the two basins. One side is the Canadian Basin, and the other is the Eurasian Basin. Warm water from the Gulf Stream flows into the basin and some water goes over the top of the mountains into the Canadian Basin. The rest goes on back into the North Atlantic. In the past, the point where the Atlantic and Pacific water met was over the Lomonosov Range. But in 1993, the meeting point had moved 600 kilometer into the Canadian Basin, bringing a layer of warm water 50 meter thick with it. Scientist hypothesize that because of global warming the Gulf Stream is bringing more warm water north than it used to. The speed with which the warm water is moving out and up is scary. Even without melting from below, the ice cap is about 40 percent thinner than it used to be. (A riveting development in the Arctic, The Toronto Star, November 15, 1997, Insight, page C6) According to another study using overlapping satellite pictures, arctic sea ice shrunk at a rate of 2.9% per decade between 1978 to 1996. ("Ice shifts may be tied to warming", The New York Times, November 18, 1997, Section F; page 8 science desk) Web site for scientists findings: http://www.joss.ucar.edu/sheba/
When the Arctic Sunrise, a research ship, sailed between the peninsula and the James Ross Island off the tip of the peninsula, Greenpeace member Mikiko Kukuda found it hard to believe that there was once a huge ice shelf blocking the strait. The 500 square kilometer shelf broke apart in 1995. This was the first time the ship could sail all the way around the island. Sign of the disintegration of Larsen A were huge cracks in the ice shelf and large pools of water. Similar signs are now appearing in the Larsen B shelf an Ice shelf south of James Ross Island. ("Global Warming Strikes Antarctica", The Daily Yomiuri, November 15, 1997, page 9)
Scientist examining the receding glaciers in Switzerland, believe global warming is to blame. In the last 50 years, Swiss glaciers have shrunk in volume by 50%. 200 have disappeared completely and of the remaining 1800, many are in full retreat. Swiss researchers call the situation alarming. Water runoff will have a major effect on hydroelectricity, farming, tourism. ("Receding Swiss Glaciers", CNN World Report, November 30, 1997, 1:08 PM ET transcript # 97113002V04) In Glacier National Park, glaciers are in short supply. In 1890, huge glaciers ground down the Livingston Range, filling turquoise lakes. ("Where have the glaciers gone? ", The Des Moines Register, November 2, 1997, Nation World, page 4)
Glaciers in Peru, Ecuador, and Bolivia have started to melt at an alarming rate this century, especially in the last 20 years. Since the 1950's glaciers in the Cordillera Real range in Bolivia have shortened by 25-50%. More Peruvians are killed by landslides caused by glaciers than in all the countrys recent terrorist upheavals," says Pierre Ribstein, a hydrologist from CNRS in Paris. In the most devastating avalanche, around 20,000 people in the Peruvian mountain village of Yungay were overwhelmed by 6 million cubic meters of water, which swept through their valley at 280 kilometer per hour when a glacier on the Huascaran Norte mountain slipped in 1970. More recently, waves of water up to 8 meters high were generated when a glacier or unstable land falls in to mountain reservoirs and cause them to overflow. ("There are ways of predicting the landslides that kill thousands in the Andes", New Scientist, November 1, 1997, This Week, page 25)
Melting permafrost in Alaska damages roads, airports and building foundations. Dates of ice breaking up in the Tanana River each spring have been recorded for 80 years; three of the four earliest dates are in the 1990s. Records of warm summer days in Nome, Alaska show a sharp increase starting in the mid 1970s. "There is so much permafrost melting, I could not leave Fairbanks without going off the paved roads. I had to go around collapsed areas of pavement-in many places, I saw 10-15 foot holes. They looked like bomb craters.-Barry Rock University of New Hampshire. " ("Parts of Alaska starting to feel the heat ", Boston Globe September 15, 1997, Science and Technology Section, Page C1) Similar situations have been reported in the Siberia and in the Canadian arctic.
Nature magazine in its August 28th issue, reported that the area covered by Antarctic ice diminished by 25% in the period 1950-1970. Harvey Nichols of the University of Colorado also reports that the tree lines in the Canadian and Siberian arctic advanced toward the arctic circle by 60 miles, and that changes have occurred since the 1970's. Says researcher Robert Stewart of Canadian Forest Service, "We don't know what is causing this, but have clear evidence that the tree line and the permafrost are responding to warmer temperatures." (USA Today, September 9th 1997, Tuesday, Final Edition, Life Section, Page 6D)
