Melting ice

2007-08-29

in Canada, The environment

Projected Arctic ice extent 2070-2090

The Earth is developing a bald spot. No wonder so many states are clamouring to assert their Arctic claims. Of course, if they find substantial quantities of fossil fuels down there (while expending a good bit just looking) it will only make things worse.

In addition to the image above, Neal sent me this animation.

[Update: 7 September 2007] Neal put a post about this on Metafilter.

[Update: 15 October 2007] Emily Horn has posted on her blog about this: How do I fear thee? Let me count the ways.., Allen Ginsberg Has the Right Idea, Al Gore – You Win!.

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{ 19 comments… read them below or add one }

Milan August 29, 2007 at 7:54 pm

Here is another graphic from Neal, showing declining trends in ice area.

Neal August 29, 2007 at 8:04 pm

It is worth noting that the image on the right is from 2005, which previously held the record for sea ice minimum, which was shocking at the time for how drasically it deviated from the mean.

While extrapolation is extremely risky, this blog entry from May 3 demonstrates that even absent the 2007 data, arctic sea ice extent is shrinking much faster than even the most pessimistic models predict. When the present sea ice extent is factored in, the models look even more optimistic.

And even then, sea ice extent doesn’t tell the whole story, because as the two images Milan posted demonstrate, sea ice area is falling much faster because areas that were previously solid ice have disintegrated into pack ice.

Litty August 29, 2007 at 8:13 pm

Atmosphere
Cryosphere
Hydrosphere
Biosphere

Litty August 29, 2007 at 8:15 pm

That animation resembles a dying heart.

Neal August 29, 2007 at 8:40 pm

That is an apt metaphor.

. August 30, 2007 at 3:33 pm

Arctic ice cap melting 30 years ahead of forecast

WASHINGTON (Reuters) – The Arctic ice cap is melting much faster than expected and is now about 30 years ahead of predictions made by the Intergovernmental Panel on Climate Change, a U.S. ice expert said on Tuesday.

This means the ocean at the top of the world could be free or nearly free of summer ice by 2020, three decades sooner than the global panel’s gloomiest forecast of 2050.

Milan September 8, 2007 at 5:22 pm
Anon September 10, 2007 at 10:20 am

JOHN FALKINGHAM (ENVIRONMENT CANADA CHIEF FORECASTER):

I’d say that Arctic scientists generally are stunned. We haven’t seen anything quite this dramatic in… well, certainly in my 30-year career and in recorded history.

KELLY CROWE (REPORTER):

John Falkingham is chief forecaster with the Canadian Ice Service. Watching the Arctic ice is a full-time job here, and they’ve never seen anything like this before. The sea ice is melting faster than anyone predicted. It smashed through the record low a month ago, and it’s been shrinking more every day. So right now, it’s at the lowest point scientists have ever seen. This is a satellite image of the sea ice which is shown in violet. The image was taken on September 7th, 1979. Compare it to a satellite image taken today. About a third of the sea ice has disappeared. The sea ice used to cover an area of about 7.7 million square kilometres. By 2005, it had shrunk to a record low of 5.3 million, and now it has melted to a new low of just 3 million square kilometres. This data is so surprising, scientists are busy e-mailing each other, trying to figure out what is going on, but they agree on one thing…

Anon October 2, 2007 at 1:31 pm

“While experts debate details, many agree that the vanishing act of the sea ice this year was probably caused by superimposed forces including heat-trapping clouds and water vapor in the air, as well as the ocean-heating influence of unusually sunny skies in June and July. Other important factors were warm winds flowing from Siberia around a high-pressure system parked over the ocean. The winds not only would have melted thin ice but also pushed floes offshore where currents and winds could push them out of the Arctic Ocean.
But another factor was probably involved, one with roots going back to about 1989. At that time, a periodic flip in winds and pressure patterns over the Arctic Ocean, called the Arctic Oscillation, settled into a phase that tended to stop ice from drifting in a gyre for years, so it could thicken, and instead carried it out to the North Atlantic. ”

NY Times

. October 12, 2007 at 1:18 pm

The big melt: lessons from the Arctic summer of 2007

• Climate change impacts are happening at lower temperature increases and more quickly than projected.
• The Arctic’s floating sea ice is headed towards rapid summer disintegration as early as 2013, a century ahead of the International Panel on Climate Change (IPCC) projections.
• The rapid loss of Arctic sea ice will speed up the disintegration of the Greenland ice sheet, and a rise in sea levels by even as much as 5 metres by the turn of this century is possible.
• The Antarctic ice shelf reacts far more sensitively to warming temperatures than previously believed.

• Long-term climate sensitivity (including “slow” feedbacks such as carbon cycle feedbacks which are starting to operate) may be double the IPCC standard.
• A doubling of climate sensitivity would mean we passed the widely accepted 2°C threshold of “dangerous anthropogenic interference” with the climate four decades ago, and would require us to find the means to engineer a rapid drawdown of current atmospheric greenhouse gas.
• Carbon dioxide (CO2) emissions are now growing more rapidly than “business-as-usual”, the most pessimistic of the IPCC scenarios.
• Temperatures are now within ≈1°C of the maximum temperature of the past million years.
• We must choose targets and take actions that can actually solve the problem in a timely manner.
• The object of policy-relevant advice must be to avoid unacceptable outcomes and seemingly extreme or alarming possibilities, not to determine just the apparently most
likely outcome.
• The 2°C warming cap is a political compromise; with the speed of change now in the climate system and the positive feedbacks that 2°C will trigger, it looms for perhaps billions of people and millions of species as a death sentence.
• To allow the reestablishment and long-term security of the Arctic summer sea ice it is likely to be necessary to bring global warming back to a level at or below 0.5°C (a long-term precautionary warming cap) and for the level of atmospheric greenhouse gases at equilibrium to be brought down to or below a long-term precautionary cap of 320 ppm CO2e.
• The IPCC suffers from a scientific reticence and in many key areas the IPCC process has been so deficient as to be an unreliable and dangerously misleading basis for policy-making.

Milan October 13, 2007 at 2:11 pm

September 2007 polar sea ice anomaly

Video (8MB, MPEG) of arctic sea ice extent, recorded from January to September 2007. [other formats] This summer a dramatic decrease compared to previous years in the extent of the north pole ice cap was observed. Scientists are freaked out [bugmenot]. This summer, the Northwest Passage was open for a few weeks, allowing three ships to traverse it.

Anon November 8, 2007 at 12:21 am

Ice expedition tests ‘successful’
By Rebecca Morelle
Science reporter, BBC News

In 2008, explorer Pen Hadow will trek 2,000km across the North Pole, dragging a radar that will probe the thickness of the ever-shrinking ice-cap.

In advance of the expedition, the team headed to Eureka, north Canada, to test whether the instruments could perform in the tough Arctic conditions.

Mr Hadow said that the team’s “planning and hard work had paid off”.

The radar, known as Sprite, was able to make accurate ice measurements in temperatures of -35C, the team said.

. November 14, 2007 at 11:13 am

The View from Above: Using RADARSAT Satellite Technology to Monitor Sea Ice

Ice monitoring is also important for identifying changing ice conditions relevant to long-term climate issues. For example, RADARSAT-1 satellite images taken of Ellesmere Island and its surrounding ice between early August and mid August 2005 showed that a massive section of the Ayles Ice Shelf had broken away. The changing Arctic landscape can continue to be monitored closely through the use of RADARSAT data.

Anon November 21, 2007 at 4:22 pm
. December 5, 2007 at 2:14 pm

Of ice and men
Another big climate bet

“At no time between now and the end of the year 2020 will the minimum total Arctic Sea ice extent be less than 10 percent of the 1979-2000 average minimum annual Arctic Sea ice extent, as measured by NSIDC data or any other measurement mutually agreed-upon; provided, however, that if two or more volcanic eruptions with the energy level equal to or greater than the 1991 Mount Pinatubo shall occur between now and the end of 2020, then all bets are voided.”

. June 12, 2008 at 10:54 am

The recent collapse of Wordie Ice Shelf, Mueller Ice Shelf, Jones Ice Shelf, Larsen-A and Larsen-B Ice Shelf on the Antarctic Peninsula has made us aware of how dynamic ice shelve systems are. After their loss the reduced buttressing of feeder glaciers has allowed the expected speed-up of inland ice masses after shelf ice break-up. (Rignot and others, 2004).

. July 3, 2011 at 12:55 pm

Rapid melting of Arctic sea ice possibly explained
Colder, saltier meltwater could be forcing warmer water to surface
The Canadian Press
Posted: Jun 28, 2011 2:11 AM ET
Last Updated: Jun 28, 2011 3:40 PM ET

Arctic researchers have discovered a clue as to why sea ice in the North is melting so much faster than anyone thought it would.

Scientists have long puzzled over why Arctic sea ice is retreating at up to three times the rate that climate models say it should.

In an effort to answer that question, a group of U.K-based explorers walked more than 500 kilometres of sea ice in the High Arctic, taking temperature readings of the ocean below them.

They found a layer of cold, salty water about 200 metres down that they suspect has come from the melting of first-year ice.

That meltwater has forced the relatively warmer water to the surface, where it’s speeding up the decay of more ice.

Peer reviewed science! July 14, 2011 at 9:41 pm

Zhang,X. 2010. Sensitivity of summer sea ice coverage to global warming forcing: towards reducing uncertainty in arctic climate projections. Tellus 62A:220-227.

Climate change simulations with models that best replicate current sea ice conditions suggest summer Arctic sea ice cover could pass the 80% loss threshold as early as 2030.

In general, simulations with different climate models produce significantly different projections of how rapidly Arctic sea ice cover will respond to future warming. This large disagreement is primarily due to differences in how sea ice mass balance and related feedbacks are computed, and in initial sea ice conditions used at the start of the simulations. Furthermore, models have also substantially underestimated the recent rapid decline in sea ice cover. In a new study, reported on in the journal Tellus, Alaskan researcher Xiangdong Zhang assessed future sea ice projections using only that subset of climate models that were best able to replicate past observations of the sensitivity of Arctic sea ice area to changes in surface air temperatures. The range of uncertainties in projections of ice loss over the next century using this subset of models is much lower than that for the larger unconstrained ensemble of model results. The subset of constrained scenarios also indicates that summer ice area in the Arctic Ocean could decrease by more than 80% as early as 2030, and that regional mean winter and summer surface air temperatures are likely to increase by 8.5°C and 3.7°C, respectively, by 2100.

Summary courtesy of Environment Canada

. October 3, 2011 at 8:44 pm

Canadian Ice Shelves Halve In Six Years

“The CBC reports on new research that shows thousand-year-old ice shelves (much different than sea ice) are breaking up and have been reduced by half in a region of Canada over the last six years. ‘This summer alone saw the Serson ice shelf almost completely disappear and the Ward Hunt shelf split in half. The ice loss equals about three billion tonnes, or about 500 times the mass of the Great Pyramid of Giza.’ More detailed pictures can be seen at The Conversation, with a quote from Professor Steven Sherwood, Co-Director of the University of NSW’s Climate Change Research Centre: ‘The real significance of this, in my view, is that this ice has reportedly been there for thousands of years. The same is true of glaciers that have recently disappeared in the Andes. These observations should dispel in one fell swoop any notion that recent global warming could be natural.'”

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