A Greener Greenland?

The publishers of the world’s most prestigious atlas have been caught out by Cambridge scientists exaggerating the effects of climate change.

In its latest edition, the £150 Times Atlas of the World has changed a huge coastal area of Greenland from white to green, suggesting an alarming acceleration of the melting of the northern ice cap.

Accompanying publicity material declared the change reflected ‘concrete evidence’ that 15 per cent of the ice sheet around the island – an area the size of the United Kingdom – had melted since 1999.

But last night the atlas’s publishers admitted that the ‘ice-free’ areas could in fact still be covered by sheets of more than a quarter of a mile thick.

It came after a group of leading  polar scientists from Cambridge University wrote to them saying their changes were ‘incorrect and misleading’ and that the true rate of melting has been far slower.

Experts from the University’s internationally-renowned Scott Polar Research Institute said the apparent disappearance of 115,830 sq miles of ice had no basis in science and was contradicted by recent satellite images.

There are no official figures on how much ice has melted but one scientist put it at between 0.3 and 1.5 per cent of the ice sheet.

Publicity for the new atlas read: ‘For the first time the new edition has had to erase 15 per cent of Greenland’s once permanent ice cover – turning an area the size of the United Kingdom and Ireland “green” and ice-free.

‘This is concrete evidence of how climate change is altering the face of the planet for ever – and doing so at an alarming and accelerating rate.’

The seven Cambridge scientists who signed the letter are closely involved with research into changes in the Greenland ice shelf.

They do not dispute that some glaciers have got smaller but say the overall picture presented is wrong.

Glaciologist Dr Poul Christoffersen of the Scott Institute said: ‘We believe that the figure of a 15 per cent decrease in permanent ice cover since the publication of the  previous atlas 12 years ago is both incorrect and misleading.

‘We compared recent satellite images of Greenland with the new map and found that there are in fact still numerous glaciers and permanent ice cover where the new Times Atlas shows ice-free conditions and the emergence of new lands.

‘We conclude that a sizeable portion of the area mapped as  ice-free in the Atlas is clearly still ice-covered. There is to our knowledge no support for this claim in the published scientific literature.’

If the Times Atlas calculations were correct, the ice sheet would have been shrinking at a rate of 1.5 per cent per year since 1999.

The Cambridge scientists measure ice loss in volume, not area, and say it has actually decreased by 0.1 per cent in the past 12 years.

 The ice cover in the Polar regions are crucial indicators of global climate change

Graham Cogley, professor of geography at Trent University in Canada, said: ‘Climate change is real and Greenland ice cover is shrinking but the claims here are simply not backed up by science. This pig can’t fly. 

‘The best measurements in Greenland, which cover only part of the ice sheet, suggest that 1.5 per cent per year is at least ten times faster than reality.

‘It could easily be 20 times too fast and might well be 50 times too fast.’

Dr Jeffrey Kargel, a hydrologist at the University of Arizona, said it was ‘a killer mistake that cannot be winked away’.

The Times Atlas, which claims to be the ‘most authoritative’, first came out in 1895. It is not owned by The Times newspaper but is published by HarperCollins, which is owned by News Corporation.

A spokesman for HarperCollins yesterday admitted the land shown as green and described as ‘ice-free’ could be up to 500m – more than a quarter of a mile – thick.

She said: ‘I can see why you could see that as misleading.’

She said the data was provided by the U.S. National Snow and Ice Data Centre in Colorado. Its lead scientist Dr Ted Scambos said it appeared the atlas had used a map from the Centre’s website which showed ‘ice thickness’ not the extent of the ice edge.

He added that the Centre  had never been contacted by the atlas’s cartographers. 

He said: ‘That map would not be appropriate and there are many small glaciers and ice domes around the perimeter of Greenland that should have been included in the permanent ice sheet.

‘We are very surprised by the mistake because lots of people – in the U.S., Europe, Cambridge – could have steered the atlas away from this high-profile statement as ice in Greenland is fairly well mapped and the melting is nowhere near this level.

‘Was it a mistake? I can only speculate that the people promoting the map were thinking differently from the cartographers.

‘The problem is that people may think that because the melting is so much less than 15 per cent it is not something to worry about – but it is. Part of the mission of the sceptic community is to throw wrench and create confusion, when in fact there is a lot of understanding in this area.’

by "environment clean generations"

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Posted in: A Greener Greenland?,environment,glaciers,global warming,Greenland ice shelf,ice melt,Trent University in Canada

Arctic Ice Melting 50 Years Too Fast

On Aug. 19, 2007, a joint survey by the Japan Agency for Marine-Earth Science and Technology and the Japan Aerospace Exploration Agency revealed that Arctic ice was melting at a far quicker rate than anticipated. What's particularly alarming about this discovery is that the United Nations' scientific models anticipated that the ice levels measured by the Japanese team would not be reached until after 2040 -- and possibly not until 2050.

                                        This satellite image shows that Arctic ice levels in 2007 (left)
                                                          were less than even the record low levels of 2005 (right).

A researcher at the Colorado Center for Astrodynamics said that Arctic ice is melting at previously unseen rates [source: Science Daily]. The melting has caused coastal ice in parts of Canada and Alaska to become quite brittle. That ice easily breaks away in large chunks (a process known as calving) and melts in the open ocean. There's also less sea ice in the Arctic Ocean because ice has floated into the Atlantic Ocean. The previous record low for Arctic sea ice was recorded on Aug. 15, 2005, though scientists said there was a high probability that the record would be breached in 2007.

The Arctic saw another milestone in the summer of 2007. In August, the Northwest Passage had almost no floating ice. It was the first time the Passage had been completely open to shipping since people started keeping records in 1972. Scientists say that the lack of ice represents clear proof that the planet is warming. The now-open sea lane means that someone could sail from New York to Korea without encountering any ice, though bad weather is always possible. In comparison, the first explorer to navigate the Northwest Passage successfully, Roald Amundsen, took three years to get through the waterway's thick ice.

Sea ice is measured primarily through three methods: microwave scanners on orbiting satellites, buoys and observation platforms. The latter two are generally equipped with several types of measuring devices. Scientists focus their measurements on the extent of sea ice, rather than the thickness, since it's easier for satellites to measure extent. When examining sea ice, scientists look at the minimum and maximum extent, thickness, environmental conditions and changes in the melting season. The Arctic sea ice melting season usually lasts from March to the middle of September.

This record pace of Arctic ice melt has scientists concerned about rising sea levels, diminished habitats for polar bears and other animals and an impending rush for fossil fuels in the region. Increased traffic through the Northwest Passage and the Northeast Passage (which runs by Siberia) may increase pollution in the area.

Ice re-forms during winter, but due to warmer waters the amount of re-formed ice appears to be decreasing. Ice that was previously considered "permanent" is now melting. That leaves an ever-decreasing base of ice at the beginning of each melting season.

Sea ice plays an important role in keeping temperatures down around the world. Whereas sea ice reflects 80 percent of sunlight back into the atmosphere, ocean water absorbs 90 percent of sunlight [source: National Snow and Ice Data Center]. As melting ice exposes more ocean to direct sunlight, scientists expect water temperatures to rise, accelerating the ice melt.

Consequences of Melting Arctic Ice

The opening of the Northwest Passage and melting of Arctic ice has allowed access to parts of the Arctic Ocean and the seabed that have been blocked for centuries. Consequently, several countries are trying to lay claim to parts of the newly opened Arctic in hopes of getting at some of the oil and natural gas reserves that are buried under the ocean floor. Experts estimate that 25 percent of the world’s remaining fossil fuel reserves lies under the Arctic seabed [source: Guardian Unlimited]. Commentator Jeremy Rifkin noted with irony that it’s the burning of fossil fuels and the subsequent rise of global temperatures that has made it possible to access these long-blocked stores of oil and gas [source: Houston Chronicle].  

                                                   Scientists fear that increased melting of Arctic ice will lead to the 

polar bear's extinction sometime in the middle of the century.  

The 1982 Law of the Sea Treaty gives countries an economic zone extending 200 miles from their coasts, and it’s under the provisions of this treaty that some countries are trying to lay claim to parts of the Arctic. In August 2007, Russia planted a flag on the Arctic seabed, following a claim that part of the ocean floor is an extension of their country’s continental shelf. Canada, Norway and Denmark (via Greenland) are making similar claims. The United States and Canada still dispute who has the right to claim the Northwest Passage while both Denmark and Canada claim sovereignty over Hans Island.

Some commentators say that a new oil rush is underway that will further imperil the region’s delicate environment. Despite the controversy, Russia and Canada, in particular, appear to be aggressively pursuing their claims in the region. Russia is expanding its drilling operations in the waters off Siberia. Canada is spending several billion dollars to add a deep-water seaport and new patrol ships to their Arctic territory. Canada’s Prime Minister, Stephen Harper, said that “Canada’s position is that we intend our position in the Arctic area” [source: CanWest News Service].

Scientists call this rush for fossil fuels and the melting of permafrost in Siberia and other areas a “ticking time bomb” [source: Houston Chronicle]. If Siberia’s vast permafrost continues to melt, massive amounts of methane, now trapped beneath the ice, may be released. Methane is a highly potent greenhouse gas, more than 20 times stronger than carbon dioxide. Scientists fear that the release of so much methane may initiate a sort of feedback loop, wherein methane release increases the rate of global warming, in turn spurring more permafrost melt and more methane release [source: Houston Chronicle]. 

One of the more visible effects of Arctic ice melt is the calving of large pieces of ice from glaciers and ice shelves. In 2005, the Ayles Ice Island, a 30-square mile chunk of ice, broke away from Canada’s Ayles Ice Shelf and began drifting through the Arctic. Some people worried that the ice island would crash into Alaskan oil rigs in the Beaufort Sea, but as of late August 2007, it was stuck in a channel in the Canadian High Arctic, 300 miles from its original location.

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Posted in: Arctic Ice Melting 50 Years Too Fast,arctic ocean,earth,global warming,ice melt,polar bear