Thursday, January 24, 2008

CNRS enters more data on 2007 Arctic sea ice

This item just out is providing us with a good update on the hard data that is emerging around the rapid ice retreat of last summer. Those who have followed my postings know that I was a very early proponent of an accelerating ice collapse in the Arctic, simply because if we only assume a simple constant small heat imbalance year after year the results on the ground are not actually linear at all and must end with a collapse crisis.

Last year we got a really good look at what a collapse crisis will look like. The remaining question right now is if this last summer was brought on be a combination of several bits of bad luck getting us ahead of the curve or if the unusual collateral effects are merely results.

The reason that I ask this question is that last year the Arctic seemed to get more than its share of lower latitude’s warm air, sped along by a strong shifting of boreal winds. It now seems to be returning the favor by giving us lots of cold polar air this winter. Is this a new climate cycle? In other words, something has happened this past year that was both completely unexpected and not clearly understood.

It almost looks like an emergent heat pumping action that will draw surplus heat into the Arctic at a much stronger rate than in the past. All this suggests that the sea ice will continue to retreat at an even faster rate than in the past. In any event, current results are now strongly supporting a full disappearance of summer sea ice by 2012.

They are also quite right to point out that the summer of 2008 will be critical on every level. It will confirm specific new trends or even give us a sharp reversal. My own analysis really supports the thesis that we have now entered the final collapse phase of the perennial sea ice which is actually been accelerated by the specific onset of Arctic spring like conditions.

In fact my worst case scenario now would be to have a few very cold Arctic winters in which the ice loss is merely zero. However, at some point sooner or later, we will have a warm summer or two and the balance of the sea ice will be eliminated. And honestly, if this cold winter does not reward us with a significant reversal of last year’s decision, then it is really over as far as the long term perennial sea ice is concerned.

Once the summer sea ice properly clears every summer, the Greenland ice cap can now be expected to largely retreat slightly from the shoreline over the following century eventually stabilizing with quite a bit of mass loss. This will have a marginal effect on sea levels.

Arctic ice-cap loss twice the size of France: research

PARIS (AFP) — The Arctic ice cap has shrunk by an area twice the size of France's land mass over the last two years, the Paris-based National Centre for Scientific Research (CNRS) said Wednesday.

"The year 2008 promises to be a critical year on every level," said Jean-Claude Gascard, the body's research director and coordinator of European scientific mission Damocles, which is monitoring the effects of climate change across the Arctic.

September 2007 measurements show ice covering 4.13 million square kilometres (1.6 million square miles), down from 5.3 million square kilometres in 2005.

"Melting could result in the loss of another million in one (2008) summer," he added at a press conference.

"Summer 2007 was marked by a major retreat in the ice-cap, one we were not anticipating," Gascard said. "The rate of decline is also two or three times faster than (observed) beforehand."

International models used to predict retreating ice have some "catching-up" to do, he said.

Over the last 20 years, 40 percent of the ice-cap has melted with the average thickness halved from three to 1.5 metres.

Year-round ice coverage has reduced, with summer melting also lasting longer, the centre reported.

The Damocles' exploration vessel Tara has been able to cross the 5,000-kilometre Arctic Ocean in just over 16 months -- less than half the time taken by a late 19th century Norwegian explorer.

Gascard said the ship had been able to travel at "twice the pace expected by organisers, and three times the speed models suggested".

Disruption to the thermal layers of atmosphere stacked over Earth's far north was cited as the principal cause by Swedish researchers earlier this month, in a study published in the journal Nature.

The Tara team recorded a temperature of 10 degrees Celsius (50 degrees Fahrenheit) at altitudes between 500 and 1,000 metres.

"The reduction in the intensity of cold (temperatures) during winter over these last 20 years corresponds to an accumulation (rise) of 1,000 degrees Celsius," Gascard said.

The team highlighted the role of ocean currents, namely in the northern Pacific, behind warming of waters.

Gascard's research colleague, Gerard Ancellet, also spoke of recently-formed Arctic mist, pollution clouds which "trap" Earth's naturally-emitted infrared rays thereby raising temperatures.

"Internal" Arctic pollution is the source, Ancellet said, highlighting Russian and northern Scandinavian gas and oil exploitation.

Carbon dioxide emissions among the major north American, European and south-east Asian economies was not the only other factor, he added.

Shipping traffic with additional nitrogen oxide emissions is a growing complication, given he estimated that 25 percent of the increase in future maritime transport "will be confined to the Arctic zone".

In summer 2007, the Northwest Passage, historically an ice-jammed potential shortcut between Europe and Asia, was "fully navigable" for the first time since monitoring began in 1978, according to the European Space Agency.

It lasted five weeks, according to Canada's environment ministry, with 100 vessels getting through.

How come we never heard this? I assume that this was all small boats, but it would be nice to see a freighter make it through. Once the long term ice is really gone, the Arctic shipping season should be at least two months. Right now it is still a nasty speculation especially as how strongly this was effected by unusual winds in 2007.

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