Arctic death spiral: sea ice volume has collapsed

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The sharp drop in Arctic sea ice area has been matched by a collapse in total sea ice volume to one fifth of its level in 1980.

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The sharp drop in Arctic sea ice area has been matched by a harder-to-see, but equally sharp, drop in sea ice thickness. The combined result has been a collapse in total sea ice volume — to one fifthof its level in 1980.

Back in September, Climate Progress reported that the European Space Agency’s CryoSat-2 probe appeared to support the key conclusion of the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) at the University of Washington’s Polar Science Center: Arctic sea ice volume has been collapsing much faster than sea ice area (or extent) because the ice has been getting thinner and thinner.

Now the Natural Environment Research Council (NERC), the UK’s primary agency for funding and managing environmental sciences research, has made it official. In a Wednesday press release, they report:

Arctic sea ice volume has declined by 36 per cent in the autumn and 9 per cent in the winter between 2003 and 2012, a UK-led team of scientists has discovered….

The findings confirm the continuing decline in Arctic sea-ice volume simulated by the Pan-Arctic Ice-Ocean Modelling & Assimilation System (PIOMAS), which estimates the volume of Arctic sea ice and had been checked using earlier submarine, mooring, and satellite observations until 2008.

This should be the story of the day, week, month, year, and decade. As NERC notes, sea ice volume is “a much more accurate indicator of the changes taking place in the Arctic.”

Many experts now say that if recent volume trends continue we will see a “near ice-free Arctic in summer” within a decade. And that may well usher in a permanent change toward extreme, prolonged weather events “Such As Drought, Flooding, Cold Spells And Heat Waves.”

It will also accelerate global warming in the region, which in turn will likely accelerate both the disintegration of the Greenland ice sheet and the release of the vast amounts of carbon currently locked in the permafrost.

The findings were published online in Geophysical Research Letters (subs. req’d). In a U. of Washington news release, polar scientist and coauthor Axel Schweiger said:

Other people had argued that 75 to 80 percent ice volume loss was too aggressive. What this new paper shows is that our ice loss estimates may have been too conservative, and that the recent decline is possibly more rapid.

 

Researchers used new data from the European Space Agency’s CryoSat-2 satellite spanning 2010 to 2012, and data from NASA’s ICESat satellite from 2003 to 2008 to estimate the volume of sea ice in the Arctic.

They found that from 2003 to 2008, autumn volumes of ice averaged 11,900 km3. But from 2010 to 2012, the average volume had dropped to 7,600 km3 – a decline of 4,300 km3. The average ice volume in the winter from 2003 to 2008 was 16,300 km3, dropping to 14,800 km3 between 2010 and 2012 – a difference of 1,500 km3.

“The data reveals that thick sea ice has disappeared from a region to the north of Greenland, the Canadian Archipelago, and to the northeast of Svalbard,” says Dr Katharine Giles, a NERC-funded research fellow at the Centre for Polar Observation & Modelling (CPOM) at UCL (University College London), who co-authored the report, published online in Geophysical Research Letters….

Other satellites have already shown drops in the area covered by Arctic sea ice as the climate has warmed. Indeed, sea-ice extent reached a record minimum in September 2012. But CryoSat-2, launched in April 2010, differs in that it lets scientists estimate the volume of sea ice — a much more accurate indicator of the changes taking place in the Arctic.

“While two years of CryoSat-2 data aren’t indicative of a long-term change, the lower ice thickness and volume in February and March 2012, compared with same period in 2011, may have contributed to the record minimum ice extent during the 2012 autumn,” says Professor Christian Haas of York University, Canada Research Chair for Arctic Sea Ice Geophysics, co-author of the study and coordinator of the international CryoSat sea ice validation activities.

CryoSat-2 measures ice volume using a high-resolution synthetic aperture radar altimeter, which fires pulses of microwave energy down towards the ice. The energy bounces off both the top of sections of ice and the water in the cracks in between. The difference in height between these two surfaces let scientists calculate the volume of the ice cover.

The findings are the result of a huge international collaboration between teams from UCL, the European Space Agency, the Jet Propulsion Laboratory, the University of Washington, York University, Alfred Wegener Institute for Polar & Marine Research, Woods Hole Oceanographic Institution, Morgan State University and the University of Maryland.

The team confirmed CryoSat-2 estimates of ice volume using measurements from three independent sources – aircraft, moorings, and NASA’s Operation IceBridge.

If you were wondering whether “death spiral” was the right visual metaphor for the collapse of Arctic ice, Robinson has a graphic for you:

It is almost certainly too late to save the Arctic’s summer sea ice from near-total destruction. Let’s hope the same isn’t true for the biosphere. The time to act is now if we don’t want to betray our children and future generations.

This article was originally posted on Climate Progress. Re-posted with permission.

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4 Comments
  1. suthnsun 8 years ago

    “This should be the story of the day, week, month, year, and decade.” Agree entirely, can’t see why this ‘death spiral’ is not galvanizing every sentient being on the planet. Hopefully the Greens will be able to find a way to paint the dire picture in a way that even Abbot will understand. Unfortunately they are probably too busy with other (important perhaps but trivial in comparison) issues and already locked into a diagonally opposite position. So we need someone credible from outside politics to ‘paint the picture’.

    • Chris Young 8 years ago

      I’ve heard leading geoengineering expert David Keith say that he thought the data on Arctic Ice were not that convincing. I haven’t yet looked at it closely myself. But the problem here is to explain clearly why the data presented here are the right values. The public has to begin to understand just what the techniques are if they’re going to believe that things are as bad as they seem.

    • anotherbob 8 years ago

      This is not a story, it is a death sentence. What the data indicates is the irreversible decline of the Arctic reflective area and consequent runaway global warming due to melting snow and ice cover. Exposed permafrost will not only release vast amts. of CO2 and methane but will continue to warm as periods of summer solar radiation grow longer. An ever warmer Arctic is a civilization ending occurrence with decades of rapid increase in sea levels that will make the world’s coastlines and ports unlivable and unusable for hundreds of years as the oceans continue their rise due to accelerating Greenland and finally Antarctic melt. The data indicate that the tipping point came 10-20 years ago.

      The whole problem of irreversible Arctic melting is further aggravated by our short term inability to stop burning fossil fuels. Even if our brightest and best idiots who claw their way to the top had the foresight and will to convert our industrial societies to carbon neutral consumption it would take, at the very least, twenty more years of high levels of CO2 pollution; pollution that would drive the C02 concentrations well above 400ppm ensuring our worst case warming scenarios even without the effects of melting permafrost and increased Arctic solar absorption.

      I hate this conclusion and would like it if someone would provide some reasonable alternative outcome that excludes meteorite strikes, nuclear war/winter or a super volcanic eruption – any ideas folks?

  2. Andy Lee Robinson 8 years ago

    Glad you like it – I think it’s as iconic as the Hockey Stick, as it captures the magnitude of what is happening as succinctly as possible, but still packed with information and recognizable from a distance.

    The PIOMAS source data is available here, after completing a courtesy form:
    http://psc.apl.washington.edu/wordpress/research/projects/arctic-sea-ice-volume-anomaly/

    I wrote a program to simply average the volumes by month, to make a csv file for excel and then plot and design.
    Anyone can do this for themselves.

    Yes, there was some concern that the PIOMAS data seemed to be exaggerated because the data is partly modelled, but the latest Cryosat 2 results validate them, and even show that the volume decline is underestimated! That is a shock.
    This brings forward an ice free Arctic summer to as early as a couple of years from now!

    I agree that this should be headline news, but it seems that most of the Earth’s population just don’t want to know, and those with a responsibility for informing the public as it is are guilty of a gross dereliction of duty. We have some idea why this is so.

    If this year’s minimum breaks last year’s alarming record by a wide margin, then will it get the coverage and the sensible policies it deserves?
    It is already too late for Arctic summer sea ice, it’s doomed. Question is, how bad will its effect be on weather, and how quickly will the ice free duration expand in the coming years?

    The science could not be more clear – we are in big trouble as the web of life begins to unravel, but still nothing happens to try and mitigate the looming state change. There is a large amount of methane and clathrates currently locked up by low temperatures and permafrost cover, if this lot starts to go, it would be a big shame – surely any non-zero probability of this happening should be taken seriously by an intellignet species?
    It has far greater global impact than a highly localized short sharp shock of an unusually large meteroid.

    However, like frogs, people respond to short-timescale stimuli, and don’t notice the heat being gradually turned up…
    The Earth is imperceptibly warming day by day, but it’s adding up and threatening to create a world unrecognizeable to even our recent ancestors.

    The mem “climate has always changed, so it’s OK” is just like saying “people have always died so murder is OK”…
    All life is finely tuned to this climate, and it is changing too rapidly and we are the cause.
    We have a moral duty to try to preserve it, even if that means some discomfort, because that is an absolute walk in the park to the kind of climate that could arise – and we have some examples of those in our solar system already!

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