Thursday, March 24, 2011

NSIDC: Annual maximum Arctic sea ice extent reached, “tied for the lowest in the satellite record.”

On March 7, 2011, Arctic sea ice likely reached its maximum extent for the year, at 14.64 million square kilometers (5.65 million square miles). The maximum extent was 1.2 million square kilometers (463,000 square miles) below the 1979 to 2000 average of 15.86 million square kilometers (6.12 million square miles), and equal (within 0.1%) to 2006 for the lowest maximum extent in the satellite record.
On Monday, the National Snow and Ice Data Center announced the maximum, “the largest sea ice extent during a given year.”  It “marks the end of the growth period for sea ice, and the start of the melt season.”
This isn’t a big surprise since the Arctic has seen the lowest DecemberJanuary, and February(tied with 2005) sea ice extent in satellite record.  The more important three-dimensional metric of ice volume also continues its long-term decline (see Navy’s oceanographer tells Congress, “the volume of ice as of last September has never been lower…in the last several thousand years”)
Here’s more from NSIDC, plus their plot of sea ice extent:

As of March 22, ice extent has declined for five straight days. However there is still a chance that the ice extent could expand again. Sea ice extent in February and March tends to be quite variable, because ice near the edge is thin and often quite dispersed. The thin ice is highly sensitive to weather, moving or melting quickly in response to changing winds and temperatures, and it often oscillates near the maximum extent for several days or weeks, as it has done this year.
Since the start of the satellite record in 1979, the maximum Arctic sea ice extent has occurred as early as February 18 and as late as March 31, with an average date of March 6.
The graph above shows daily Arctic sea ice extent as of March 22, 2011, along with daily ice extents for 2006, which had the previous lowest maximum extent, and 2007, the year with the lowest minimum extent in September. Light blue indicates 2011, green shows 2007, light green shows 2006, and dark gray shows the 1979 to 2000 average. The gray area around the average line shows the two standard deviation range of the data.
The death spiral lives, as it were:

21 Responses to “NSIDC: Annual maximum Arctic sea ice extent reached, “tied for the lowest in the satellite record.””

  1. Wonhyo says:
    So far, the data shows a gradual (but study) decline in sea ice extent. Are there any scientific estimates for if or when the decline will accelerate and just go to zero?
    Is there any conceivable way to reverse, or at least stop, the decline in the near-to-mid term? Clearly, a reduction in CO2 is required for long term stabilization.
  2. Lou Grinzo says:
    Check the Arctic sea ice volume (not extent) at the link below. The ice is going away even quicker than the extent trend indicates. ArcticSeaiceVolume/ images/BPIOMASIceVolumeAnomalyCurrent.png
  3. With less sea ice we can expect stronger winter storms, according to some research.
    With less sea ice we have another positive feedback for destabilizing seabed methane hydrates. Possible resulting in underwater landslides which could create tsunamis. The methane amount is so great that it shrinks all human emissions and could render affords to stabilize Co2e within the atmosphere impossible.
    With less sea ice ocean currents will likely change, which directly affects weather and wave formations.
    With less sea ice we lost reflective ice, the dark water beneath can now absorb sunlight and further accelerating ocean warmth in shallow waters. Resulting warmer waters will further accelerate ice mass lose.
    Land ice lose has the potential to cause earthquakes and other forms of geomorphological response.
    Given that there wasn’t much geomorphological activity for quiet some time, the response might be rather abrupt and of high magnitudes.
    When does the world start to act at large, rather then watching the catastrophe unfold?
  4. idunno says:
    Also worth looking at are the maps available from the TOPAZ system.
    Click through to the following page, and plot a map of the Arctic ice thickness using the variable “hice”.
    The latest date available is 24 February 2011, in the following format:
    20110224. Try that against 20100224, and 20090224.
    The Norwegian blue canary is looking fairly unsteady on its perch.
    I hope everybody here knows why miners carried canaries into coalmines. Because soon we are going to have to start worrying about the canary-killer. Methane.
    Melt one thousand cubic kilometres of surface sea ice, and you get one thousand cubic kilometres of liquid seawater.
    Melt one thousand cubic kilometres of seabed permafrost (methane clathrates) and you get only 800 cubic kilometres of seawater, and 168,000 cubic kilometres of methane. If you want to make a properly explosive mixture of this, you should add 6 times the quantity of air =
    2,004,000 cubic kilometres of air.
    Such a pity that Dubya and Dick were no great fans of Kubrick’s early work.
  5. MapleLeaf says:
    Serreze has a very article in Nature on the possible “tipping” point of Arctic sea ice. icelights/ 2011/ 03/ 09/ arctic-sea-ice-and-the-tipping-point/
  6. K. Nockels says:
    Volume loss this summer should be very interesting to witness. I wonder how many ships will run the northwest passage? or how many oil companies
    will be rushing to secure drilling rights?
  7. Adam R. says:
    Prokaryotes says:
    When does the world start to act at large, rather then watching the catastrophe unfold?
    Instead, there will be national–and feckless–panic reactions to national catastrophes.
    Global issues are ever hostage to national politics.
  8. catman306 says:
    What could a tsunami do to an oil drilling platform?
    What about a massive atmospheric methane explosion?
  9. idunno says:
    Hi All,
    I have made a stupid mathematical error in my previous post. You don’t add 6 times as much air, you as 5 times as much air, which added to the methane, finally makes 6 times as much. Hope this is now clear. The perfect explosive mix is 2,004,000 cubic kilometres.
    Thousands of cubic kilometres is the correct unit of measurement, as per the PIOMAS graph posted on Comment 2.
    Also, there is a slight ambiguity in which of Kubrick’s films I am referencing: not “Spartacus”, but “Dr Strangelove”.
    The critical point being that you are supposed to tell people after you have constructed the “Doomsday Device”.
    You are NOT, on being briefed by NASA, supposed to appoint one of your campaign PR goons to prevent anybody at NASA mentioning the “clathrate gun hypothesis” ever again.
    The clathrate gun would now appear to be smoking. See the research by Sakharova and Similev 2010.
    Prompting, for me, the question of “what did the President know, and etc…”
    I should confess at this point, that I am not an American, and I have not the benefit of an American education, and I am a little bit hazy about your legal code. I seem to remember that you have always refused to ratify the jurisdiction of the International Criminal Court. So you will probably have to deal with this as an internal matter.
    But when I was at school, we out here in the boondocks were taught that the people fully conscious and responsible for the deliberate gassing to death of 6 to 7 million people were really quite naughty.
    Of course, this is not to compare like with like.
    An atmospheric test-firing of the “clathrate gun” would probably lead to the deaths of 6 to 7 billion (that’s billion, not million) people, and, if we are very lucky, will not result in the any thing like the event of 251 million years ago, when 96% of species became extinct – “the Great Dying”.
    Anyway, I am starting to ramble a bit, so I better finish up…
    …with a couple of questions…
    1. Do you have any laws in America?
    2. Do you have any journalists?
    Just asking.
    P.S. Anybody having problems following the technicalities can Google any term between quotation marks.

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