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Vocapedia > Earth> Climate change, Global warming > Glaciers, Polar regions





Illustration: Brendan Monroe


Public Attitudes About Climate Change

The Opinion Pages|Letters


APRIL 14, 2014



















A crack in the ice formed on the lagoon.

The frozen lagoon provides the residents of Shishmaref

with access to the mainland.


Photograph: Nima Taradji


Nowhere to Go Amid Alaska’s Melting Ice

By Rena Silverman


Mar. 4, 2016































polar regions        UK










the planet's poles > experience extreme heat        USA










polar melt > rising oceans        USA










avoid the melting of the polar ice caps








ice shelf        USA














ice sheet        USA












melting ice sheets        UK










West Antarctic ice sheet        USA










collapse        USA










ice loss        UK





















Paris accord rift


Monte Wolverton        Cagle       4 June 2017








































glaciers        UK / USA






















































































































Alaskan glacier        USA






climate change > warmer winters > Alaska
















Himalayan glaciers        UK












Captured on camera:

50 years of climate change in the Himalayas        UK        2009


Series of before and after panoramas

of Imja glacier taken five decades apart

highlights dramatic reduction

of Himalayan ice










glacial lakes        UK


















Iceland        USA

















glaciologist        UK






glaciologist        USA






global warming > rising sea levels        USA






global warming / climate change > desert cities        UK






climate disaster        UK






eco disaster        UK






temperatures        UK
















melt        UK














melt        USA


















melt away        USA












melting        USA










melting ice        USA












The world's melting glaciers        UK










glacier melt        UK










Big Melt        USA










thaw        USA


the-big-thaw-how-russia-could-dominate-a-warming-world - Dec. 16, 2020








thawing Arctic permafrost        UK

















thawing permafrost > Climate change hits Alaska's national parks








Alaska’s melting ice        USA

















Tanzania > Mt. Kilimanjaro ice cap        USA










break loose        USA












Corpus of news articles


Earth > Climate change, Global warming


Glaciers, Polar regions




Twilight of the Glaciers


July 29, 2011

The New York Times



AN hour or so up ahead, at the higher elevations along the trail that leads over Siyeh Pass, huckleberries were ripening. Even a dawdling day hiker like me knows that huckleberries can quickly mean grizzlies in Glacier National Park. I indulged a nervous tic and patted around for the loud red aerosol can on my belt, whose label reads Counter Assault. It’s effective as a bear repellent, but even more reliable at making an urbanite feel faintly ridiculous.

I was in northwest Montana for the hikes and the huckleberries, but most of all to experience the namesake glaciers, which, I had recently learned, might be around for only another decade or so. Given that a century and a half ago there were 150 and now there are 25, the trip makes me an enlistee in the practice known by a somewhat prickly term: last-chance tourism.

For now, though, there are still glaciers to be seen. The park’s skein of well-maintained trails traverses every section of its million-plus acres and can accommodate any level of ability, from backpackers to the sheets-and-coverlets crowd. Even visitors who prefer to commune with nature through a car window can be awed by the views of the Jackson and Blackfoot Glaciers from Going-to-the-Sun Road, the often car-choked highway that more or less bisects the park west to east.

And for those who want to get closer, some serious legwork over steep terrain can put you right next to both the Grinnell and Sperry Glaciers, respectively a day and an overnight’s hike away. There are other glaciers to be glimpsed in the distance during a hike, but they can’t be reached by trails. These are excursions that require ice ax, ropes or crampons: the well-sequestered Pumpelly Glacier, for example, at 8,420 feet, and its close neighbor, the Pumpkin Glacier.

Other glaciers are nearer a trail, but still display their remote and frigid glory at some distance, and in a way the craggy surroundings make them even more vivid. I chose the Siyeh Pass Trail because it affords a prolonged, spectacular view of the Sexton Glacier from below.

Alpine glaciers like Sexton don’t look like peaks or cubes. A couple of miles into the hike, as the trail opened into a valley, it came into view: a massive, ragged smear of snow-laden ice, perched just under the sawtooth granite skyline.

My audio track, meanwhile, was the cascading water of Baring Creek, which runs parallel to much of the trail. Descending from the glacier, it charges over a series of red-rock ledges and then makes its way down into the azure St. Mary Lake far below.

As the trail continued, the bottom edge of Sexton became visible — a violent crumble, broken loose by gravity and temperature. Glaciers are forceful, slow-flowing rivers of ice. With binoculars, I could see Sexton’s thickness and true magnitude. The perspective also offers, if you’re up for it, a rather stunning view into the future. As I pushed ahead, a graying volunteer ranger approached me at a nimble gait. No bears sighted, he reported. (O.K.!) He was a veteran of decades here, it turned out. We craned our necks up at the still-formidable Sexton, and he said that it had once looked far larger to him. I read later that it has, in fact, lost at least 30 percent of its surface area since the mid-’60s.

There are several measures of what qualifies as a glacier. One generally accepted rule of thumb is that they are a minimum of 25 acres in size. The most recent report has Sexton at 68.

I moved on, ascending the switchbacks that pull the Siyeh trail up toward the 8,000-foot pass. I was well above tree line by now, and only a few peaks away from the Canadian border. Not far off, out on the moraines, a quartet of mountain goats appeared, munching and then settling.

A good idea. I was tired, too. According to Stephen Ambrose’s “Undaunted Courage,” which follows the cross-country trek of Meriwether Lewis and William Clark, Lewis was able to bushwhack 30 miles in a day. I was going to do 11, and without the whacking. (The Lewis and Clark expedition came within sight of these mountains in 1806.)

As I rested I heard women’s voices come from up the trail, sounding like an exuberant traveling book group. They seemed delighted to find a sprawled, worn-out guy to greet in passing. “How do you like it? This is our backyard!” the leader announced, adding that they were from Kalispell, Mont., just southwest of the park. I responded in superlatives, and asked whether folks here talk much about what’s happening with the glaciers.

There was a pause and the temperature seemed to decline a degree or two. “God will take care of everything we need,” one said.

“I don’t think man has anything to do with that,” her friend put in.

(A bartender at one of the lodges, not-authorized-to-speak-publicly-on-the-matter, confided that not all locals share these views.)

After a bit, they warmed enough to point out some huckleberry bushes nearby. (This is a popular shrub around here, and not just for bears; after a few days in the area, I can attest to the virtues of locally marketed huckleberry beer, jam, pie, syrup, Riesling, lip balm, French toast, soda, cobbler, lemonade, ice cream, daiquiris, tea and milkshakes.)

Retracing my steps back down to the trailhead, I was alone again — not a wise practice, according to park brochures. Lewis recounted that one grizzly, already shot four times through the lungs, charged and dispersed a six-man hunting party while its stalwarts were still firing. Still, over the past hundred years, and despite tens of millions of visitors, only 10 fatal grizzly attacks have been recorded here. They do, however, take up a fair portion of mind space.

The Siyeh Pass Trail can either be an extended loop or a somewhat shorter out and back of about 11 miles — the option I chose. As I headed back down into the valley it wasn’t much of a stretch to think of the looming Sexton as alive. The pressure of the glaciers’ weight causes the ice to flow forward over the landscape; colder temperatures allow for a buildup of ice, which speeds up the flow. Heat — a warmer day, season or era — is the competing force, and the glaciers ebb. That movement is a defining feature, part of what makes glaciers distinct from your more prosaic all-year patches of snow.

The day before, I had spoken with Daniel Fagre, who coordinates climate change and glacial geology studies here for the United States Geological Survey. He is a 20-year veteran of research at the park. The retreat of the glaciers began around 1850, he said, as part of a slow, natural climatic variation, but the disappearing act has accelerated during the last hundred years. Until recently, his research projected that, as global warming hit its stride, the park’s glaciers would all be gone by the year 2030. Now he thinks it may be as soon as 2020.

Outsize snows this past winter, which kept many park roads and trails closed well into July, could briefly forestall the meltdown, but the longer warming trend is inexorable, he said.

No reprieve? “No, I think we are continuing on that path,” he said.

The science is preliminary, but it’s clear that this loss will be more than aesthetic for the park’s ecosystem, he said. Those glacial reservoirs provide a steady supply of cool meltwater through hot summers and dry spells, helping to sustain a constellation of plants and animals, some rare — big-horned sheep, elk and mountain goats among them.

Passing again under the glacier as daylight faded, the trail neared its end. Those prospective losses weighed heavily — nostalgia, of a sort, laced with dread.

MORE pleasantly, the park celebrates nostalgia of a different sort — from the Art Deco typography on the official signage to the fleet of low-slung, roll-top tour buses known as “red jammers,” which date from the ’30s. These ply the roads between robber-baron-era hotels, offering full- and half-day tours to various sections of the park ($30 and up).

There’s a wealth of accommodations along the eastern and western boundaries of the park, especially in the towns of East Glacier Park and West Glacier. Despite their names, these towns, with populations of only a few hundred each, are more like distant cousins than identical twins. West Glacier, half an hour from the Kalispell airport, is generally newer, and sprawls.

East Glacier Park, two and a half hours north of the Great Falls, Mont., airport, is a charming, tumbleweedy throwback with a string of weathered eateries and motor-court lodgings that are only slightly post-World War II. There’s also the Backpacker’s Inn, a combination hostel and super-cheap motel with a mostly youthful clientele who like the clean, spare single rooms for $30 a night. I’ve stayed in each of these places a time or two, but this night — after a fiery, pepper-laden dinner of enchiladas pasillas at Serrano’s Mexican restaurant among a crowd of other glacier-gawkers and local ranchers — I opted for the Mountain Pine Motel. It has endured, with appearance and ambience intact, since 1947. The owners are descendants of the pioneer Sherburne family that helped settle the park area in the 1890s.

Nearby is the century-old Glacier Park Lodge, a grandly creaky log cabin writ very large. There are three such concessioner-run legacy hotels at the park, erected by the Great Northern Railroad to lure tourism. My favorite is the Many Glacier Hotel, a darkly comical but generally comfortable old wooden monstrosity with a Swiss theme (the bellhops wear lederhosen). Its broad verandas face a transfixing view of a horizon of pinnacles that surround Swiftcurrent Lake — one of 131 named lakes in the park (631 others are as yet unnamed; feel free to follow my example and name a few after your friends).

When my wonderful clawfoot tub leaked onto the occupants of the room below, the two repair-crew guys who showed up grinned and shrugged after some futile work: that’s kind of the way this place is, they said. The only other available room was infested with bats, and smelled like it, I was told. It was a great stay, just the same. Half of the hotel is being renovated all this season and is closed, along with one of the dining rooms.

The Many Glacier Hotel is also the start of one of the park’s most popular hikes, to Grinnell Glacier. The 8- or 10-mile hike is strenuous, though less so than the Siyeh Pass Trail, and the payoff is that you can get within a stone’s toss of the glacier itself, the surface area of which is more than twice Sexton’s.

I embarked with a ranger-guided group on Chief Two Guns — a trim 45-footer, built locally and hauled up here somehow 50 years ago — for a quick trip over Swiftcurrent Lake. Then a short walk to another boat, the even older Morning Eagle, across Lake Josephine to the trailhead. The boats moved past a shifting panorama of jagged rock faces, slender waterfalls, and high above, the destination glacier. The trail is often crowded, but that scarcely registers in these surroundings. Hikers stop to catch a breath and find it taken again by the view out over the string of lakes, far below, fed by Grinnell’s meltwater. Connected by cascades, each lake is a deeper blue than the one above.

After three hours of steady ascent and a final quarter-mile of hard climbing, the trail ends at the foot of the glacier and an iceberg-studded, expanding lake. The lake does not appear on old maps, according to the ranger. It is a byproduct of the fact that Grinnell’s surface is 40 percent smaller than a half-century ago.

Above the lake, the glacier is a wide, tilted skirt of ice whose hem you can almost touch, brilliant under the sun even when it’s dirty with wind-blown grit by the end of the season. It seems immense, too big to disappear, and nearly crowds everything else from consciousness. The ranger said that until a few seasons back you could walk out onto the lower edge of it, which is too thin now to bear human weight safely.

Seaweed-like stromatolite fossils embossed in the cracked rocks along the trail supply a Precambrian perspective of perhaps a couple of billion years. But it is the view out over this lake of meltwater that grabs the imagination far more urgently.

A question hangs up there with the remnant glacier, which may soon be converted to a few patches of ice: what comes next?

Hikes and Huckleberries



You can reach Glacier by flying into Kalispell, Mont., and driving half an hour to the west side of the park, or flying into Great Falls and driving two and a half hours to reach the eastern entry point. You can also take Amtrak’s Empire Builder from Chicago, Seattle or Tacoma, and disembark at either East Glacier Park, Essex or West Glacier. The Going-to-the-Sun Road has been under repair since last year, which means that traffic is often rerouted to a single lane. This results in stops that can add 30 or 40 minutes to the usual one- or two-hour trip.

The Logan Pass parking lot and visitor center is usually posted “Full” by midmorning all summer, according to park staff members. A shuttle bus system along the Going-to-the-Sun Road ferries hikers and sightseers to and from Logan Pass and a series of trailheads.



At East Glacier Park:

Both the Glacier Park Lodge and, to the north, Many Glacier Hotel (for both 406-892-2525; glacierparkinc.com/reservations.php; both from $140 a night for two in high season) are concessioner “legacy” railroad hotels — gracious dowager empresses that can’t help but show their age.

The Backpacker’s Inn, right behind Serrano’s Mexican Restaurant (29 Dawson Avenue; 406-226-9392; serranosmexican.com) and under the same ownership, is $30 a night for a single room, $12 a night for the gender-segregated hostel. Clean, quiet, spartan. Serrano’s has benches on the porch for its surplus of patrons — a mix of locals, tourists and backpackers who line up for the chimichangas and carne Tampico. The super-smoky habanero sauce is sold at the cash register.

At West Glacier:

The Silver Wolf Log Chalets (406-387-4448; silverwolfchalets.com; from $176) are cabins with interior décor that is almost exclusively logs, twigs and sticks, quiet and nicely appointed, 10 minutes from the park.

The Belton Chalet (406-888-5000; beltonchalet.com; from $155) is a lovely old hotel with predictable advantages and limitations. Keep in mind that a railroad line is close at hand. The restaurant is one of the best at this edge of the park.

In the park:

There are 13 national park campgrounds, many with views of lakes and peaks, including those at Apgar Lake, Medicine Lake or Swiftcurrent Lake. Cook a porterhouse or two over the iron grill, bring in a bottle of malbec and observe all bear precautions.





East Glacier Park, Mont., is a small tourist town whose water system is not reliably safe, according to state and federal authorities. Motels connected to that system are required to post a “boil order” warning, but some don’t, which could mean trouble if you’re unaware and brush your teeth or drink water from the tap in your room. (Boiling kills giardia, E. coli, cryptosporidium and other potentially illness-producing microorganisms not reliably filtered out by the current water operation, said Shelley Nolan of the Montana Department of Environmental Quality.)

A few places, including the big Glacier Park Lodge, have their own wells or water filtration, so the water is safe to use without boiling. Restaurants should use bottled water. So ask.

A new water treatment plant is set to begin operation soon, according to the federal Environmental Protection Agency, but as of this writing, it’s not certain that will occur in 2011.




is the author of “Millipedes and Moon Tigers:

Science and Policy in the Age of Extinction.”

He teaches journalism and environmental studies

at the University of Richmond.

Twilight of the Glaciers,





Warming Is Seen

as Wiping Out Most Polar Bears


September 8, 2007

The New York Times




WASHINGTON, Sept. 7 — Two-thirds of the world’s polar bears will disappear by 2050, even under moderate projections for shrinking summer sea ice caused by greenhouse gases in the atmosphere, government scientists reported on Friday.

The finding is part of a yearlong review of the effects of climate and ice changes on polar bears to help determine whether they should be protected under the Endangered Species Act. Scientists estimate the current polar bear population at 22,000.

The report, which the United States Geological Survey released here, offers stark prospects for polar bears as the world grows warmer.

The scientists concluded that, while the bears were not likely to be driven to extinction, they would be largely relegated to the Arctic archipelago of Canada and spots off the northern Greenland coast, where summer sea ice tends to persist even in warm summers like this one, a shrinking that could be enough to reduce the bear population by two-thirds.

The bears would disappear entirely from Alaska, the study said.

“As the sea ice goes, so goes the polar bear,” said Steven Amstrup, lead biologist for the survey team.

The report was released as President Bush was in Australia meeting with Asian leaders to try to agree on a strategy to address global warming. Mr. Bush will be host to major industrial nations in Washington this month to discuss the framework for a treaty on climate change.

The United Nations plans to devote its general assembly in the fall to global warming.

A spokeswoman for the White House declined to comment on the report, saying it was part of decision making at the Interior Department, parent of the survey.

In the report, the team said, “Sea ice conditions would have to be substantially better than even the most conservative computer simulations of warming and sea ice” to avoid the anticipated drop in bear population.

In a conference call with reporters, the scientists also said the momentum to a warmer world with less Arctic sea ice — and fewer bears — would be largely unavoidable at least for decades, no matter what happened with emissions of heat-trapping gases like carbon dioxide.

“Despite any mitigation of greenhouse gases, we’re going to see the same amount of energy in the system for 20, 30 or 40 years,” said Mark Myers, the survey director. “We would not expect to see any significant change in polar conditions regardless of mitigation.”

In other words, even in the unlikely event that all the major economies were to agree to rapid and drastic reductions in emissions of carbon dioxide and other heat-trapping gases, the floating Arctic ice cap will continue to shrink at a rapid pace for the next 50 years, wiping out much of the bears’ habitat.

The report makes no recommendation on listing the bears as a threatened species or taking any action to slow ice cap damage. Such decisions are up to another Interior Department agency, the Fish and Wildlife Service, which enforces the Endangered Species Act. That decision is due in January, officials have said. The wildlife agency had to make a determination on the status of a threatened species because of a suit by environmental groups like Greenpeace and the Natural Resources Defense Council.

In some places, the bears have adapted to eating a wide range of food like snow geese and garbage. But the survey team said their fate was 84 percent linked to the extent of sea ice.

Separate studies of trends in Arctic sea ice by academic and government teams have solidified a picture of shrinking area in summers for decades to come.

A fresh analysis by scientists of the National Oceanic and Atmospheric Administration, to be published Saturday in the journal Geophysical Research Letters, says sea-ice coverage of the Arctic Ocean will decline by more than 40 percent before the summer of 2050, compared with the average ice extent from 1979 to 1999.

This summer the ice retreated much farther and faster than in any year since satellite tracking began in 1979, several Arctic research groups said.


John H. Broder reported from Washington,

and Andrew C. Revkin from New York.

Warming Is Seen as Wiping Out Most Polar Bears,






A message

from the melting slopes of Everest

The sons of Hillary and Tenzing
speak out about climate change:
"Believe us, it's a reality"


Published: 06 July 2007

The Independent

By Cahal Milmo and Sam Relph


Fifty-four years after Sir Edmund Hillary and Tenzing Norgay became the first men to scale Everest, their sons have said the mountain is now so ravaged by climate change that they would no longer recognise it.

On the eve of the Live Earth concerts this weekend, Peter Hillary and Jamling Tenzing yesterday issued a timely warning that global warming is rapidly changing the face of the world's highest mountain and threatening the survival of billions of people who rely on its glaciers for drinking water.

The base camp where Sir Edmund and Norgay began their ascent is 40 metres lower than it was in 1953. The glacier on which it stands, and those around it, are melting at such a rate that scientists believe the mountain, whose Nepalese name, Qomolangma, means Mother of the World, could be barren rock by 2050.

Up to 40,000 Sherpas who live at the base of the Himalayas face devastation if vast new lakes formed by the melted ice burst and send a torrent of millions of tons of water down the slopes.

Mr Hillary, who has himself twice reached Everest's summit, said: "Climate change is happening. This is a fact. Base camp used to sit at 5,320 metres. This year it was at 5,280 metres because the ice is melting from the top and side. Base camp is sinking each year. For Sherpas living on Mount Everest this is something they can see every day but they can't do anything about it on their own."

The warning came as a survey revealed that most Britons remain unconvinced about the extent of climate change and that terrorism, crime, graffiti and even dog mess are more pressing issues for the UK. The Ipsos-Mori poll found that 56 per cent of people believe scientists are still debating whether human activity is contributing to climate change. In reality, there is virtual consensus that it is.

Just over half of people, 51 per cent, believe climate change will have little or no effect and more than one-third admitted they were taking no action to reduce their carbon emissions.

Speaking before the seven Live Earth concerts, which organisers hope will be a catalyst for action on global warming, Jamling Tenzing, who has also climbed Everest, said the mountain was serving as an early warning of the extent to which it is already changing the planet.

The glacier where Sir Edmund and Norgay pitched their base camp before eventually reaching the summit at 29,000ft on 29 May 1953 has retreated three miles in the past 20 years. Scientists believe that all glaciers in the Himalayas, which are between half a mile and more than three miles in length, will be reduced to small patches of ice within 50 years if trends continue.

Mr Tenzing said: "The glaciers have receded a great deal since my father's time. There are many things he wouldn't recognise today. The glacier on which base camp sits has melted to such a degree that it is now at a lower altitude. I think the whole face of the mountains is changing."

The glacial retreat presents a double peril for those who live in the Himalayas and the populations of India and China, where the water flowing from the mountains accounts for 40 per cent of the world's fresh water.

The rapid increase in the rate of glaciers melting - from 42 metres a year in the 40 years to 2001 to 74 metres a year in 2006 - has resulted in the formation of huge lakes in the space of a few years.

A United Nations study of the 9,000 glacial lakes in the Himalayas found that more than 200 are at risk of "outburst floods", unleashing thousands of cubic metres of water per second into an area where 40,000 people live. In 1985, Lake Dig Tsho in the Everest region released 10 million cubic metres of water in three hours. It caused a 10-metre-high wall of water which swept away a power station, bridges, farmland, houses, livestock and people up to 55 miles downstream. Scientists estimate that the most dangerous lakes today are up to 20 times bigger. One of those, Imja Tsho, did not exist 50 years ago and lies directly above the homes of 10,000 people.

The worst-case scenario according to Nepalese scientists is a cascade effect whereby one overflowing lake empties into another, starting a chain reaction which would kill thousands and wipe out agriculture for generations.

Peter Hillary said: "I've seen the result of glacial lakes bursting their banks and it's just catastrophic. It's like an atomic bomb has gone off. Everywhere is rubble. The floods of the past are unfortunately nothing compared with the size of what we are currently threatened with."

In the longer term, scientists believe the depletion of the glaciers will drastically reduce the flow of water into the nine major rivers fed by the Himalayan glaciers.


Defra recruits critic of Bush

An outspoken critic of President George Bush's approach to combating global warming has been appointed to advise the British Government on climate change.

Bob Watson was voted out of his job chairing the United Nations-sponsored Intergovernmental Panel on Climate Change (IPCC) five years ago after incurring the wrath of the Bush administration. He will take over as chief scientific adviser at the Department for the Environment, Food and Rural Affairs (Defra) in September. The appointment was approved by Gordon Brown.

His recruitment, a week after Mr Brown took over as Prime Minister, will be seen as further evidence the Government is trying to distance itself from Mr Bush. Last week, he caused consternation at the White House when he appointed Sir Mark Malloch Brown, a strong critic of US foreign policy, as minister for Africa, Asia and the United Nations.

Dr Watson, a British-born expert on atmospheric pollution, advised former US President Bill Clinton on the environment and worked at the World Bank before becoming the IPCC's chairman. The US began manoeuvring to remove him shortly after President Bush's inauguration in 2001. A year later, he was replaced by Rajendra Pachauri, an Indian scientist.

Environmental groups uncovered a memo from the US oil corporation ExxonMobil, a major contributor to Mr Bush's election campaign, asking the White House to unseat Dr Watson because he had an "aggressive agenda". At the time, Dr Watson acknowledged the US government's intervention was an "important factor" in the campaign to oust him.

A Defra spokeswoman said: "He was the unanimous choice out of all the candidates."


Nigel Morris

A message from the melting slopes of Everest,







Antarctica Ice Sheet Stable


June 27, 2007

Filed at 1:57 a.m. ET

The New York Times



WELLINGTON, New Zealand (AP) -- An ice sheet in Antarctica that is the world's largest -- with enough water to raise global sea levels by 200 feet -- is relatively stable and poses no immediate threat, according to new research.

While studies of the Greenland and West Antarctic ice sheets show they are both at risk from global warming, the East Antarctic ice sheet will ''need quite a bit of warming'' to be affected, Andrew Mackintosh, a senior lecturer at Victoria University, said Wednesday.

The air over the East Antarctic ice sheet, an ice mass more than 1,875 miles across and up to 2.5 miles thick centered on the South Pole, will remain cold enough to prevent significant melting in the near future, the New Zealand-led research shows.

But it eventually may become vulnerable to the effects of rising sea levels driven by the melting of other ice sheets, Mackintosh's team found. Their research was published this week in the journal Geology.

''The East Antarctic ice sheet is the largest and the coldest and is going to be the last to respond in any great way'' to global warming, he said. ''Our research suggests changes in sea levels due to global warming will not be caused by changes in the East Antarctic Ice Sheet yet.''

The researchers found that from 13,000 to 7,000 years ago, when sea levels rose by more than 330 feet, the East Antarctic ice sheet thinned by 660 feet to 1,150 feet. Rising waters during that period would have lifted the buoyant ice sheet's edges off its rocky base, causing pieces to detach or ''calve'' and melt.

If the sheet experienced such calving again, even small changes could have a significant impact, the researchers said.

The study -- conducted with Australia's Macquarie University and the Australian Nuclear Science & Technology Organization -- did not predict how much sea levels would have to rise before the sheet's edges started to break away.

Glaciologist Wendy Lawson, head of geography at Canterbury University who took no part in the study, said the new research supported previous modeling indicating the sheet was stable.

''There is no short-term risk as far as the overall magnitude of the East Antarctic ice sheet goes,'' she said.

Researchers: Antarctica Ice Sheet Stable,
AP-Antarctica-Ice-Sheet.html - broken link






Many Arctic Plants

Have Adjusted

to Big Climate Changes,

Study Finds


June 15, 2007

The New York Times



Many Arctic plant species have readily adjusted to big climate changes, repeatedly recolonizing the rugged islands of the remote Svalbard archipelago off Norway’s coast through 20,000 years of warm and cool spells since the frigid peak of the last ice age, researchers report in today’s issue of the journal Science.

Their finding implies that, in the Arctic at least, plants may be able to shift long distances to follow the climate conditions for which they are best adapted as those conditions move under the influence of human-caused global warming, the researchers and some independent experts said.

Some experts on climate and biology who were not involved with the study, which was led by scientists from the University of Oslo, said it provided a glimmer of optimism in the face of generally bleak scientific assessments of the vulnerability of ecosystems to the atmospheric buildup of greenhouse gases.

Terry L. Root, a biologist at Stanford who has been involved with many studies concluding that plants and animals are measurably feeling the effects of human-driven warming, described the Svalbard research as “great news.”

“The large number of documented changes has created quite a concern about the fate of many species,” Dr. Root said. The new study, she said, shows that “some Arctic plants, and hopefully vegetation in other areas, apparently are able to respond in a manner that compensates for the rapid warming.”

Norwegian and French scientists analyzed the DNA of more than 4,000 samples of nine flowering plant species from Svalbard, a group of islands between the Scandinavian mainland and the North Pole. They said they found genetic patterns that could be explained only by the repeated re-establishment of plant communities after the arrival of seeds or plant fragments from Russia, Greenland or other Arctic regions hundreds of miles away.

The wide dispersal of the plants presumably occurs through a combination of Arctic winds, driftwood or dirt carried in floating ice and bird droppings, the scientists said.

Julie Brigham-Grette, a geosciences professor at the University of Massachusetts, said the findings were consistent with research from Alaska showing that forests had extended farther north during a period, warmer than the present, that peaked around 11,000 years ago.

“As the proper habitat is available, plants will survive,” she said. “I have not seen this demonstrated so clearly as it is in this paper. If dispersal is not a limiting factor, then maybe the rate of warming ongoing in the Arctic will not be a limiting factor in plant survival in distant places.”

Inger Greve Alsos, the study’s lead author, said natural adaptability in the plants might be tested if the projections for rapid Arctic warming from the United Nations Intergovernmental Panel on Climate Change came to pass. She also cautioned that the evidence for resilience and long-distance mobility in Arctic plants could be the exception, not the rule.

The ability of Arctic flora to disperse widely is probably an evolutionary consequence of the region’s tendency toward sharp climate swings, she said.

Many Arctic Plants Have Adjusted to Big Climate Changes, Study Finds,










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