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BornFromTheVoid

2013 Arctic Sea Ice Extent Maximum

Sea Ice Extent Maximum  

14 members have voted

  1. 1. What do you think the Sea Ice Extent Maximum will be in 2013 in millions of km2?

    • Higher than 16.0
      0
    • 15.9 to 16.0
      1
    • 15.8 to 15.9
      0
    • 15.7 to 15.8
      1
    • 15.6 to 15.7
      0
    • 15.5 to 15.6
      2
    • 15.4 to 15.5
      0
    • 15.3 to 15.4
      1
    • 15.2 to 15.3
      1
    • 15.1 to 15.2
      2
    • 15.0 to 15.1
      0
    • 14.9 to 15.0
      0
    • 14.8 to 14.9
      2
    • 14.7 to 14.8
      0
    • 14.6 to 14.7
      1
    • 14.5 to 14.6
      1
    • 14.4 to 14.5
      0
    • 14.3 to 14.4
      0
    • 14.2 to 14.3
      1
    • 14.1 to 14.2
      0
    • 14.0 to 14.1
      0
    • Lower than 14.0
      1


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The melt season has finished and so it's time to start looking towards the spring maximum (if we make it past 21/12/12!).

The maximum sea ice extent has typically diminished at a much slower rate than the minimum, with a difference of only around 1.9 million km2 between the lowest and highest maximum (11.3%), compared to 4.2 million km2 for the minimum (55.2%).

The highest maximum extent value recorded was in 1979 at 16,564,600km2, while the lowest was 2011 at 14,689,100km2.

Here's a graph of the annual sea ice extent 1 day maximum based on the NSIDC data

post-6901-0-63888100-1349041076_thumb.jp

The last 10 years

2003 15.5868

2004 15.2555

2005 14.9462

2006 14.7330

2007 14.7896

2008 15.3052

2009 15.1628

2010 15.2845

2011 14.6891

2012 15.2909

We'll use the NSIDC data to base the minimum on. I don't think this will be submitted to anything, and the voting is set to private, just in case that matters to anyone.

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I have a hankering after major changes to the ice within the basin this year?

I think we may see the ice factory set up again across Bering if changes to the Arctic's energy budget are it's driver but these will be more than offset by open water remaining in Beaufort, Baffin and Laptev/east Siberian sectors?

i still cannot believe the sst anom off the Alaskan shelf (west of the McKenzie delta?) and cannot put it down to 'faulty readings' as too many measurements are taken in the area? The most 'plausible' explaination I have heard mooted is the extension of a Pacific warm water current into the basin , Via Bering, and it's deflection under Coriolis pressures to the coast where the current grounds out forming the sharp temp spike?

We also have the possible extension of the N.A.D. into Barrentsz and Kara and the 'New' occurences in Laptev which again hints at a warm surface current emerging?

If the Jet so organises this year as to place the 'cold plunges' over land then the accompanying WAA may well help keep ice thin and vulnerable in areas of the basin for long periods through winter?

I also wonder about the mixing that must be occuring from the 'outgassing' under the east Siberian Sea? Last year the thickness there was pegged to under 1m. If this was partly due to outgassing and warm waters mixed back to the surface then this years melt will have only aided this process (remember last sept we were told that features there had grown up to ten times larger than the previous year? has this scale of increase continued this year?).

All in all we may start to see winter ice following the large losses we have seen in summer ice. Whatever happens though I'd guess the volume will be down and that the ice will be spread out thinner than ever?

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I just see that after most low minima, there is a jump in the following maxima, so I think this March the extent will climb to just a little below the average of the last 7 or 8 years.

I'd imagine the extra fresh water from the melt may help with a thin refreeze, as well as the strong cold anomalies around the Bering sea from the continuing -ve PDO helping to bolster the ice in that area.

But I'm sure opinions will change if the sea ice growth remains below average for the next few weeks.

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As with the summer ice i believe that the ice thickness , or lack of it, must impact the winter season once we drop below a certain threshold? We all saw what a strong storm was capable of doing over summer (with open water allowing swells to form) and I feel that below a certain threshold we could find a similar disruption over winter with slabbing and over-riding opening up enough ocean to allow further disruption and mixing in the basin?

Let us also not forget the the wrong synoptics over winter has also lost us a large proportion of the older thicker ice, via export out of Fram, to further weaken the pack/thin the pack.

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GW: That's an error in the model - has to be. It doesn't even show up in all the models: compare these two:

http://ocean.dmi.dk/...te/index.uk.php

http://polar.ncep.no...y_NPS_ophi0.png

Edit: The Coriolis explanation is from a random commenter on Neven's blog and is absolute drivel. Betrays a fundamental misunderstanding of both Coriolis forces and indeed thermodynamics.

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Re the above: I sent an email to the query address on the model front page. No reply as yet, but they must have prodded something as the temperatures and anomalies now show saner values.

http://polar.ncep.no...t/rtg_high_res/

http://polar.ncep.no...t_NPS_ophi0.png

http://polar.ncep.no...y_NPS_ophi0.png

A salutary reminder that much of what people like us obsess over on blogs is simply a set of auto-updated web-pages with little manual oversight, which form a very small part of the work being done by the actual scientists involved. Obviously something was wrong here, but not something important enough to come to notice earlier.

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Thanks for that songster!

It also highlights why we should use more than one source and get a feel for what we ought to be seeing from readings? Kinds like Lincolnshire's 'supercell' on yesterdays 3:30pm MetO radar image!!

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Almost forgot about this.

Having reached 14.26 million already, the lowest vote is out of the game. Feeling quite confident about my 14.8-14.9 guess so far.

Less than 3 weeks to the date of the earliest maximum recorded, February 21st in both 1996 and 1987.

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Going by the one day NSIDC extent, the maximum appears to be 15.169 million km2. Two people voted for between 15.1 and 15.2 million, so congrats to whoever did!

So overall, 16.66% of the voters got it right, 50% went too high and 33.33% went too low.

If the sea ice extent follows a general linear trend, we could expect the maxima to average below 15 million from next year onward.

post-6901-0-47466700-1364389661_thumb.jp

Anywho, unless someone decides to do one first, I will probably set up the first minimum prediction poll this weekend.

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  • Similar Content

    • By BornFromTheVoid
      Poll number 4 of the summer. The average guess from the last poll was 3.54 million, up from 3.03 million in May, but with a lot less votes.
      After a slow melt in June, most extent and area measures are mixed, with 2016 somewhere between lowest and 3rd lowest on record. With volume, 2012 now has a clear lead, while 2016 now sits in 3rd, quite close to 2010, 2011 and 2013. With the weather looking highly favourable for melt over the next 10 days, lowest on record is still very much a possibility.
      Here are the daily minima since 2000, and the 80s and 90s averages.

       80s     6.963
       90s     6.423
      2000    5.943
      2001    6.567
      2002    5.625
      2003    5.969
      2004    5.770
      2005    5.314
      2006    5.746
      2007    4.147
      2008    4.548
      2009    5.047
      2010    4.590
      2011    4.333
      2012    3.340
      2013    5.040
      2014    4.988
      2015    4.341
      As always, voting is set to private.
    • By BornFromTheVoid
      This is the 3rd sea ice minimum poll of the summer. The previous poll, posted on May 5th, had an average of 3.03 million km2 after 21 votes, while the April poll average 3.48 million from 16 votes.
      At the moment, we are still lowest on record by about half a million km2 going by most area and extent calculations, and lowest or 2nd lowest by volume. The sensor calibration is underway at the NSIDC and we should hopefully have the full official extent data back again soon. For now, we are going by the uncalibrated data provided by Wipneus.
      Here are the daily minima since 2000, and the 80s and 90s averages.

       80s     6.963
       90s     6.423
      2000    5.943
      2001    6.567
      2002    5.625
      2003    5.969
      2004    5.770
      2005    5.314
      2006    5.746
      2007    4.147
      2008    4.548
      2009    5.047
      2010    4.590
      2011    4.333
      2012    3.340
      2013    5.040
      2014    4.988
      2015    4.341
      As always, voting is set to private.
    • By BornFromTheVoid
      This is the 2nd sea ice minimum poll of the summer. The previous poll, posted on April 5th, had an average of 3.48 million km2 after 16 votes.
      At the moment, we appear to still be lowest on record going by most area and extent calculations, and lowest or 2nd lowest by volume. Unfortunately, there was an issue with on the sensors used for calculating the NSIDC extent values used here, so we may not have NSIDC extent data for a few months.
      Here are the daily minima since 2000, and the 80s and 90s averages.

       80s     6.963
       90s     6.423
      2000    5.943
      2001    6.567
      2002    5.625
      2003    5.969
      2004    5.770
      2005    5.314
      2006    5.746
      2007    4.147
      2008    4.548
      2009    5.047
      2010    4.590
      2011    4.333
      2012    3.340
      2013    5.040
      2014    4.988
      2015    4.341
      As always, voting is set to private.
    • By BornFromTheVoid
      We're at the end of June and things are looking mixed in the Arctic.
       
      After a large May melt phase, including about 3 weeks up to the first week of June as the lowest extent on record, declines began to slow just as previous years declines accelerated. This means we've gone from lowest on record to about 6th or 7th lowest over the last 3 weeks or so, and we're now about 600k above 2012.
       
      PIOMAS volume is still down around 6th lowest up to the end of May, while the DMI's new volume measures have us closer to the bottom 3 on record.
       
      At the moment it appears all to play for, but if we don't see a serious acceleration in the melt rate this month, the chances of a bottom 3 finish will be very slim.
       
      Below are the September daily lows up to 2014

       
      As always, votes are set to private
       
       
       
      EDIT: The poll didn't seem to save? Can a mod add one in (it's exactly the same as last months poll) or do I need to start a new thread?
    • By BornFromTheVoid
      Now that we're entering the full swing of the melt season, I thought it would be time for the first sea ice minimum poll of 2015.
       
      (Most ice info used here is based on the daily NSIDC daily sea ice extent data, unless otherwise stated).
       
      We've just come out of a very mild, though not exceptionally so, winter which saw the lowest sea ice maximum on record by most area and extent measures.
       
      925hPa temps north of 70N ......... ............. .............. Maximum Sea Ice Extent
       
       
       
      The early part of the melt season has seen temperatures well above average across most of the Arctic, with sea ice extent generally in the bottom 3 on record, with the daily value of 12,531,000km2 being the 2nd lowest for May 16th (most recent).
       

       
      On the other hand, sea ice volume has continued to slowly grow from the minimum in 2012, with April 2015 the 7th smallest volume on record.
       

       
      There is a long way to go this melt season, but the forecast for the near term shows things warming up across much of the Arctic with temperatures climbing well above freezing, especially across the Pacific side, around the Beaufort/Chukchi regions, so a good chance of an accelerated melt period over the next 7 days.
       

       
       
      After that, who knows? 
       

       
       
      (Votes are set to private, for anyone concerned about that)
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