Total Arctic sea ice at record low in 2010: study

500 MILES FROM THE NORTH POLE Mon Sep 5, 2011 6:18pm EDT

Ice breaks away from a frozen coastline near the Norwegian Arctic town of Longyearbyen April 23, 2007. REUTERS/Francois Lenoir

Ice breaks away from a frozen coastline near the Norwegian Arctic town of Longyearbyen April 23, 2007.

Credit: Reuters/Francois Lenoir

Related Topics

500 MILES FROM THE NORTH POLE (Reuters) - The minimum summertime volume of Arctic sea ice fell to a record low last year, researchers said in a study to be published shortly, suggesting that thinning of the ice had outweighed a recovery in area.

The study estimated that last year broke the previous, 2007 record for the minimum volume of ice, which is calculated from a combination of sea ice area and thickness.

The research adds to a picture of rapid climate change at the top of the world that could see the Arctic Ocean ice-free within decades, spurring new oil exploration opportunities but possibly also disrupted weather patterns far afield and a faster rise in sea levels.

The authors developed a model predicting thickness across the Arctic Ocean based on actual observations of winds, air and ocean temperatures.

"The real worrisome fact is downward trend over the last 32 years," said Axel Schweiger, lead author of the paper, referring to a satellite record of changes in the Arctic.

He was emailing Reuters at the Greenpeace icebreaker Arctic Sunrise, in the Arctic Ocean between the Norwegian island of Svalbard and the North Pole.

"(It fell) by a large enough margin to establish a statistically significant new record," said the authors in their paper titled "Uncertainty in modeled Arctic sea ice volume."

The researchers at the University of Washington in Seattle checked the model results against real readings of ice thickness using limited submarine and satellite data.

The approach has some detractors because it is focused is on modeling rather than direct observations of thickness, and therefore contains some uncertainty.

Sea ice area is easier to measure by satellite than ice thickness, and so has not needed a modeling approach.

Ice thickness is just as important or more so in helping understand what is happening in the far north. Some experts argue that part of the reason the ice area has dramatically fallen in recent years is because it has been thinning for decades.

The authors said their Pan-arctic Ice Ocean Modeling and Assimilation System (PIOMAS) in general agreed well with actual observations, although "modeling error" was possible.

The Arctic sea ice area fell below 4.6 million sq km last week with two weeks of the melt season still to go, compared with the record low of 4.13 million sq km in 2007.

By comparison, the minimum ice extent in the early 1970s was about 7 million square km. Ice melts every year during the summer and reaches a minimum extent in mid-September.

Most experts now agree that the Arctic Ocean will be ice-free in late summer at some point this century but disagree about exactly when.

While sea ice itself does not raise sea levels when it melts, a warmer Arctic could speed up melting of the Greenland ice sheet, which is freshwater ice trapped over land and contains enough water to raise world sea levels by 7 meters.

FILED UNDER:
We welcome comments that advance the story through relevant opinion, anecdotes, links and data. If you see a comment that you believe is irrelevant or inappropriate, you can flag it to our editors by using the report abuse links. Views expressed in the comments do not represent those of Reuters. For more information on our comment policy, see http://blogs.reuters.com/fulldisclosure/2010/09/27/toward-a-more-thoughtful-conversation-on-stories/
Comments (3)
leigh456 wrote:
True to form, the models all show a great amount of warming etc whereas the actual measurements don’t. The conceit of those who think that we truly understand what all the significant factors are that drives our climate and that they can thus “model” what is going to happen well into the future should first demonstrate that inputting data from the distant past into the models and coming up with “predictions” that at least somewhat match the climate record. It is only very recently that the climate hysterics have been forced to accept that we can’t even predict cloud formation which has been proven to be at least partly if not mostly caused by cosmic rays.

This whole thing is an interesting study but sadly the science has been castrated by dogma, kind of like happened to scientists in the distant past whose observations contradicted dogma.

Sep 06, 2011 3:08pm EDT  --  Report as abuse
everybodyelse wrote:
everyone has a right to have an opinion on the subject.

however, it’s also fair to point out that the opinions expressed by the very vocal minority (like that of leigh456) represent a tiny fraction of the scientific opinion on the subject.
The overwhelming majority of respected, internationally recognized groups and organizations (by “overwhelming majority” i mean all of them) dealing with the actual science of climate change accept the IPCC findings. that is: 1) the climate is changing, 2) humans are likely a major cause, and 3) if we don’t do something about it we’re very likely in trouble.
the denialist voice is a loud one but in terms of consistency with mainstream, peer reviewed, respected science, the denialists’ views are on par with alien abduction theorists, JFK conspiracy theorists, and other assorted tin hat people type fare. when you hear them screaming from way out in left field (as i’m sure you will) just keep in mind where that voice is coming from.

Sep 06, 2011 12:35am EDT  --  Report as abuse
CTF wrote:
Bravo, everybodyelse!!

Sep 08, 2011 2:13pm EDT  --  Report as abuse
This discussion is now closed. We welcome comments on our articles for a limited period after their publication.

Photo

California's historic drought

With reservoirs at record lows, California is in the midst of the worst drought in decades.  Slideshow