Sea ice pic

I used to like the IJIS sea ice pic for comparing this year’s progress. And them AMSR went down (I hope I’ve got that right, I really wasn’t paying attention) and they stopped updating. But C points me to

which, while not so pretty, is a good substitute. That comes from http://gfspl.rootnode.net/index.php/arcticiceart which has others.

This post was mostly for me to link to the pic for my own convenience. But we could also look at it… too early to tell, but we seem to be bumping along at the bottom of the range at the moment. Time will tell.

Comments

  1. #1 Nick Barnes
    2012/02/25

    The Barents sea has no ice, and the Kara sea is pretty much buggered, but the Bering has plenty.

  2. #2 Hank Roberts
    2012/02/25

    So, this is a case where a cycle is obviously happening, and the question is whether there’s a detectable trend laid over the cycle. How come we don’t see a Spencer-type curve laid over the sea ice annual ups and downs to prove, er, whatever?

  3. #3 L. Hamilton
    2012/02/25

    Here’s a pretty clear trend in minimum sea ice area, based on Cryosphere Today’s data:
    http://img.photobucket.com/albums/v224/Chiloe/Climate/2011_sea_ice_CTN_min.png

    But not just the minimum is going down — there are significant declines in both area and extent, for each month of the year:
    http://img.photobucket.com/albums/v224/Chiloe/Climate/Cycle_Arctic_extent_6.png

  4. #4 crandles
    2012/02/25

    >”and the question is whether there’s a detectable trend laid over the cycle”

    No, I am afraid not:
    http://img.photobucket.com/albums/v224/Chiloe/Climate/Cycle_Arctic_extent_6.png

    It is easy to see there clearly is a downward trend, the questions are how steep and whether the downward acceleration in the trend is significant:

    ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Sep/N_09_plot.png

    How apparant does the curve have to become before straight line should be replaced with a suitable curve?

    [That is indeed a good question. Not yet, I'd say -W]

  5. #5 crandles
    2012/02/26

    >”[That is indeed a good question. Not yet, I'd say -W]”

    Fair enough, it probably isn’t time to *replace* it yet.

    However shouldn’t we have both a straight line and a suitable curve soon if not already? It would indicate a level of uncertainty in the ‘current trend’ rather better than a single straight line does, wouldn’t it?

    [Let's wait until the spring. I'll have to work out what to say about the ice this year, then -W]

  6. #6 Markus Fitzhenry.
    2012/02/26

    In the AR4 Summary For Policymakers

    Antarctic sea ice extent continues to show interannual variability and localised changes but no statistically significant average trends, consistent with the lack of warming reflected in atmospheric temperatures averaged across the region. {3.2, 4.4}
    ————–

    Don’t really have to say more than that to you William.

    [Up to now, our bets have been about Arctic sea ice, because it is more exciting. If you have a prediction about Antarctic ice, which differs enough from other peoples opinions to be worth betting on, do let us know -W]

  7. #7 GillDolores
    2012/02/27

    With the goal to forestall the errors in the mini dissertation, this should be good to buy the interesting knowledge referring to this topic at the thesis service online. That’s more easy to reach the academic success taking this great way.

  8. #8 Harry
    2012/02/27

    “But in this case – as the link I provided before shows – the plagiarism is a marker for something worse: that Wegman simply didn’t know his stuff. He ripped off other people’s work because he didn’t understand the material well enough to write his own.”

    Poor McIntyre. Amazing how the Great Auditor’s powers failed him at this crucial time in his career.

  9. #9 Phil Hays
    2012/03/02

    The Arctic is changing rapidly. The thickest parts of the Arctic sea ice seem to be melting faster and at a more consistent rate than the thinner parts.

    http://www.nasa.gov/topics/earth/features/thick-melt.html

    Above is a press release. Paper is at:

    http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00113.1

    Text seems to be at:

    http://hdl.handle.net/2060/20110008253

    Or can be searched for at

    http://ntrs.larc.nasa.gov/search.jsp

    [Yeeeess.. Not sure that paper says much that is new. And the bits that are new (like the idea of an 8-9 year period like the Antarctic Circumpolar wave) look dodgy, to me. Comiso is largely and observationalist, from memory -W]

  10. #10 Phil Hays
    2012/03/02

    Perhaps not much new, but far more new than in the latest email scandal.

    The 8-9 year period is something that I would like to follow over the next decade and see if it persists. Finding patterns in noisy data that disappear after looking at more data is an old story.

  11. #12 Daniel
    2012/03/26

    Hi William (et al.),

    I am interested in betting on this year’s arctic sea ice minimum, or more accurately, trading stock relating to it on the iPredict.co.nz prediction market. Since the demise of the AMSR instrument, I was hoping you could tell me what is the most reliable, and comparable, current measure. The topic is currently being discussed on the iPredict New Stock Ideas forum: https://www.ipredict.co.nz/forum/read.php?12,16562

    If anyone could advise me it would be greatly appreciated.

    Daniel

    [Hopefully you'll have more luck with the "et al." than with me, since they seem to be paying more attention. I'd use whatever is the source of the figure I posted, which (I'm guessing) is back to SSMI, though I haven't actually checked -W]

  12. #13 crandles
    2012/05/15

    You may want to go back to IJIS now it is back and CT is having server problems.

    IJIS now uses:
    • Jan. 1980 – Jul. 1987 : SMMR
    • Aug. 1987 – May 2002 : SSM/I
    • Jun. 2002 – Oct. 2011 : AMSR-E
    • Oct. 2011 – the present : WindSat

    http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

    or old style pic

    http://www.ijis.iarc.uaf.edu/en/home/seaice_extent_prev.htm

    [Ah, thanks for that. Good - I'm glad they're back -W]

  13. #14 crandles
    2012/05/15

    >”they’re back”

    Impressively quick to know CT is also back ;-)

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