The scientific community is slowly waking up to the reality that this current collapse of long term sea ice, unless reversed and that is also no small trick now, is going to be complete as early as five years or by 2012. It took them a year from my own postings last year, but then it was reasonable to see what happened this year. What happened is that there was no significant reversal.
We may now be about to embark on a decadal strong chilling of the northern hemisphere but that is the minimum requirement to reverse what is going on. If not and with only a normal climate as of the past twenty years, we can expect to see the majority of the long term ice to be gone by 2012.
Meanwhile, this year as of a few days ago, both the Northwest Passage and the Northeast Passage opened up for navigation for the first time ever. I am pleased to see that the Northeast Passage opened. This was a normal year in terms of winds and the like and I had despaired of this passage ever been opened. In fact the map as of Sunday showed the Northeast Passage cleared back from land by huge distances and taking the presence of a major island whose name I have not checked to partially present a risky choke point if the winds were to shift.
This could mean that we are entering an era in which it will become normal for both passages to open up for a month or so. This fact has not been lost on ship owners who are contemplating a short direct route between the Atlantic and the Pacific for the first time.
Some of the more enthusiastic are calling for an ice free Arctic. I do not see that at all. I expect to see winter ice driven into packs that survive the summer and then migrate and get broken up the next summer. What we have lost is stable areas of accumulating sea ice that become very thick and steel like.
Actual navigation to the area of the North Pole will continue to be an adventure while the two passages can become busy and successful ocean routes.
While the areal extent is still likely slightly more than last year, it is distributed more normally this year and I have little reason to think that the loss of gross perennial ice is not continuing.
In the meantime we continue to get opining over the fate of the Greenland ice cap. My answer to that is nothing much. It did not disappear during the Bronze Age which was warmer for two thousand years, although that may also reflect the persistence of extensive remnants of the Laurentide ice sheet in the Arctic. If that is in fact the case, then perhaps we need to worry.
However, it looks more stable than that and the most we need fear is a modest retreat of the glaciers which we are in fact seeing. And again, the only way that the sea level is going to rise is if we see an abrupt collapse of a major part of the Greenland ice cap. We are nowhere near that.
This winter promises to be major test of competing ideas about global temperatures and the next five years will determine a lot about the relationship to sunspot activity. We will need to revisit this theme, but in the meantime we can enjoy the last days of the arctic summer.
Arctic ice may melt completely within ten years.
There are worrying reports that the Arctic sea ice is melting at a faster rate than last year, despite the colder weather. Information from the US National Snow and Ice Data Center (NSIDC) shows that the year began with ice covering a larger area than at the beginning of 2007. However by the beginning of summer the ice had diminished to the same levels as June last year – breaking the records for sea ice loss. The ice is melting easily as it is so thin and scientists are now predicting that the Arctic seas may be ice-free during the summer within five to ten years.
“We had a bit more ice in the winter, although we were still way below the long-term average,” said Julienne Stroeve from NSIDC in Boulder, Colorado. “So we had a partial recovery. But the real issue is that most of the pack ice has become really thin, and if we have a regular summer now, it can just melt away”.
Despite NASA’s reports in March, that the area covered by sea ice had increased slightly from 2007, most of the ice is thin, formed during the previous winter. It is more fragile than the thicker, less saline floes that have been around for several years.A few years ago, scientists were predicting that the Arctic ice would have melted in the summer by about 2080. Then computer models started projecting earlier dates, around 2030 to 2050. In the summer of 2007 the Arctic sea ice reduced to the lowest amount ever recorded; 4.2 million sq km from 7.8 million sq km in 1980. By the end of last year, a research group had predicted the ice melting entirely as early as 2013.
“I think we're going to beat last year's record melt, though I'd love to be wrong,” said Dr Stroeve. “If we do, then I don't think 2013 is far off any more. If what we think is going to happen does happen, then it'll be within a decade anyway.”
Despite this eminent loss off ice being environmentally catastrophic, countries surrounding the Arctic are seizing up the economic opportunities that melting ice could expose. Canada and Russia are exploring sovereignty claims over tracts of Arctic seafloor, while President George Bush has recently encouraged more oil exploration in US waters, possibly with intent to extend the exploration to reserves off the Alaskan coast.
In their rush to maximize the situation economically, countries are not reflecting enough upon the climatic problems this will cause. Greenland has already lost ice into the ocean, contributing to the gradual rise in sea levels. The Arctic ice cap could increase sea levels globally by about seven metres if it all melted. Natural climatic cycles such as the Arctic Oscillation play a role in year-to-year variations in ice cover. Many scientists feel that the ice is now so thin there is little hope of preventing the melting cycle.
“If the ice were as thick as it was in the 1970s, last year's conditions would have brought a dip in cover, but nothing exceptional. But now it's so thin that you would have to have 0an exceptional sequence of cold winters and cold summers in order for it to rebuild,” said Dr Ian Willis, from the Scott Polar Research Institute in Cambridge. This does not bode well for the future of the Arctic ice.
For the first time in human history, the North Pole can be circumnavigated
Melting ice opens up North-west and North-east passages simultaneously. Scientists warn Arctic icecap is entering a 'death spiral'
By Geoffrey Lean, Environment Editor
Sunday, 31 August 2008
Open water now stretches all the way round the Arctic, making it possible for the first time in human history to circumnavigate the North Pole, The Independent on Sunday can reveal. New satellite images, taken only two days ago, show that melting ice last week opened up both the fabled North-west and North-east passages, in the most important geographical landmark to date to signal the unexpectedly rapid progress of global warming.
Last night Professor Mark Serreze, a sea ice specialist at the official US National Snow and Ice Data Center (NSIDC), hailed the publication of the images – on an obscure website by scientists at the University of Bremen, Germany – as "a historic event", and said that it provided further evidence that the Arctic icecap may now have entered a "death spiral". Some scientists predict that it could vanish altogether in summer within five years, a process that would, in itself, greatly accelerate.
But Sarah Palin, John McCain's new running mate, holds that the scientific consensus that global warming is melting Arctic ice is unreliable.
The opening of the passages – eagerly awaited by shipping companies who hope to cut thousands of miles off their routes by sailing round the north of Canada and Russia – is only the greatest of a host of ominous signs this month of a gathering crisis in the Arctic. Early last week the NSDIC warned that, over the next few weeks, the total extent of sea ice in the Arctic may shrink to below the record low reached last year – itself a massive 200,000 square miles less than the previous worst year, 2005.
Four weeks ago, tourists had to be evacuated from Baffin Island's Auyuittuq National Park because of flooding from thawing glaciers. Auyuittuq means "land that never melts".
Two weeks later, in an unprecedented sighting, nine stranded polar bears were seen off Alaska trying to swim 400 miles north to the retreating icecap edge. Ten days ago massive cracking was reported in the Petermann glacier in the far north of Greenland, an area apparently previously unaffected by global warming.
But it is the simultaneous opening – for the first time in at least 125,000 years – of the North-west passage around Canada and the North-east passage around Russia that promises to deliver much the greatest shock. Until recently both had been blocked by ice since the beginning of the last Ice Age.
In 2005, the North-east passage opened, while the western one remained closed, and last year their positions were reversed. But the images, gathered by Nasa using microwave sensors that penetrate clouds, show that the North-west passage opened last weekend and that the last blockage on the north- eastern one – a tongue of ice stretching down to Russia across Siberia's Laptev Sea – dissolved a few days later.
"The passages are open," said Professor Serreze, though he cautioned that official bodies would be reluctant to confirm this for fear of lawsuits if ships encountered ice after being encouraged to enter them. "It's a historic event. We are going to see this more and more as the years go by."
Shipping companies are already getting ready to exploit the new routes. The Bremen-based Beluga Group says it will send the first ship through the North-east passage – cutting 4,000 nautical miles off the voyage from Germany to Japan – next year. And Canada's Prime Minister, Stephen Harper, last week announced that all foreign ships entering the North-west passage should report to his government – a move bound to be resisted by the US, which regards it as an international waterway.
But scientists say that such disputes will soon become irrelevant if the ice continues to melt at present rates, making it possible to sail right across the North Pole. They have long regarded the disappearance of the icecap as inevitable as global warming takes hold, though until recently it was not expected until around 2070.
Many scientists now predict that the Arctic ocean will be ice-free in summer by 2030 – and a landmark study this year by Professor Wieslaw Maslowski at the Naval Postgraduate School in Monterey, California, concluded that there will be no ice between mid-July and mid-September as early as 2013.
The tipping point, experts believe, was the record loss of ice last year, reaching a level not expected to occur until 2050. Sceptics then dismissed the unprecedented melting as a freak event, and it was indeed made worse by wind currents and other natural weather patterns.
Conditions were better this year – it has been cooler, particularly last winter – and for a while it looked as if the ice loss would not be so bad. But this month the melting accelerated. Last week it shrank to below the 2005 level and the European Space Agency said: "A new record low could be reached in a matter of weeks."
Four weeks ago, a seven-year study at the University of Alberta reported that – besides shrinking in area – the thickness of the ice had dropped by half in just six years. It suggested that the region had "transitioned into a different climatic state where completely ice-free summers would soon become normal".
The process feeds on itself. As white ice is replaced by sea, the dark surface absorbs more heat, warming the ocean and melting more ice.
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