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Arctic sea ice minimum 2012…

By popular demand, a thread devoted to the continuing decline of Arctic sea ice, and a potential new record minimum this year. As before, the figures are hot-linked and will update day-by-day.

JAXA Sea ice extent:

Cryosphere Today sea ice concentration (interactive chart):

Estimated sea ice volume from UW PIOMAS (updated every month):

Other links: Tamino, the very informative and detailed Neven’s sea ice blog , and some interesting predictions from Gareth Renowden.

195 Responses to “Arctic sea ice minimum 2012…”

  1. 101
    Dan H. says:


    You do realize that we have limited temperature data for Greenland, and what we do have does not offer much in the way of specific annual temperatures. The paper does compare the data to recent thermometer measurements with reasonable agreement. Yes, we were discussing temperatures in Greenland during the Viking settlements. There have also been Viking artifacts found in New England and the upper Great Lakes region, but there is doubt as to whether the Vikings actually ventured that far, or traded with others who carried them inward. We can only speculate as to the route travelled, or their extent in North America.

    The evidence is sparce, but if you have anything to add, please do so to further the discussion. Otherwise, we will have to go on what evidence we have, which does exist, as per the papers.

  2. 102
  3. 103

    #98 Dan H, your sarcasm misses the point, in fact you flat out don’t get it;

    “weather patterns to claim climate shifts”

    The greater disappearance of the Polar region cooler atmosphere during summer because there is less or when there will be no sea ice is a climate shift event causing different weather.

    “Repeated weather patterns would be a better indication”

    Repeated over many years indicates a climate shift.

    “By the way, snow is a rarity in South Africa. It has not snowed in Pretoria in decades, and this was the first recorded snowfall in all nine South African districts simultaneously.”

    And so it snowed in Argentina a few years ago, therefore it must be a global cooling
    a climate shift.

    “Not sure what Antarctica night has to do with South Africa. Being just south of the Tropic of Capricorn, the minimum winter sunlight is still ten hours.”

    There it is Dan, in plain sight, I wonder where the cold air comes from? The sahara??? I am clearly impressed. You really don’t understand climate nor weather, don’t quit your regular job.

  4. 104
    Susan Anderson says:

    Dan H. It is always easier to destroy than to build, and you have been busy here and no doubt elsewhere, trying to destroy the painstaking work of scientists trying to build a better understanding, and bystanders like me who at least appreciate what they are attempting to do in the face of a lot of dirty fighting.

    Your reckless disregard for the truth is exceptional.

    I am willing to bet you long odds that in 20 years (I’d say 10 or even 5, but IMNHSO the kryptonite shell of ignorant resistance you are wearing will require your little island of sand to be completely surrounded before you acknowledge you are wrong) you will be completely bereft of reality-denying arguments, say $1000 at odds 5:1.

  5. 105
    Unsettled Scientist says:

    Dan H, you’re all over the place and didn’t even read your own source. I should have known better than to address you directly. I’ll do it once more just to point out how you’re spreading confusion.

    > I think you may be confusing the Little Ice Age with the Viking colonization of Greenland, when temperatures plunged to -32.5C. That period was several centuries later, from about the 16th to 19th centuries.

    No, I got the temperature from the paper you linked. Please open the PDF, scroll down a few page to Figure 1 like I said in my first reply, and look at the year 1000 in the middle graph. Once again, you fail to understand your own source. It helps the conversation if you read what I wrote about your source, then go read the paper to see that what I’m talking about. It is before the MWP, as were the Vikings. But I should know better than to expect you to read your own sources and represent them faithfully. I’ll definitely not be going down this particular rabbit hole any further.

    PS – as Craig Nazor notes using decadal averages to discuss interannual variability is pointless. If I go from 100 to 0 in 10 years, you can point at a decade where it was 50 all ten years and they have the same decadal-mean. Not useful.

  6. 106
    dbostrom says:

    Given typical regional temperatures in SA during the winter but adding atypical atmospheric moisture for that season, why should snow be terribly surprising, or notable except as confirmation of what reasonable to expect?

    Rain and snow. Surprising, if you’re used to a dry winter.

  7. 107

    Danh, you’re a bit behind the curve when you write that “historical extent of the floating sea ice cannot be determined by proxies.”



    Not to mention:


    There’s also a ton of methodological papers on the “IP25” marker. This whole area of research looks kind of hot right now, if you’ll pardon the pun.

  8. 108

    Come to think of it , the fact that the North Pole is ongoing a dramatic seasonal ice-scape change while Antarctica remains essentially intact has very large consequences outside of the hemispheres isolated by the equatorial divide. In Particular ENSO, but not uniquely so. I Imagine that a warmer Northern hemisphere as opposed to a cooler Southern Hemisphere has equally consequences needing modelling. For instance Hadley cell winds should be diminished (a la Lindzen) exacerbating the formation of super El-Ninos.

  9. 109

    Has any information surfaced whether or not the salinity of Arctic surface water increased following the storm of Aug6. If so, this would indicate that the storm mixed deeper, warmer, saltier Atlantic water into the surface and would help to explain the increase in the slope of the ice extent graph. This water is only one to 2.5 degrees above the melting point of ice but one meter depth of 1 degree water has enough heat to melt 12.5mm of ice. There is more than enough heat available to melt all the ice many times over. How effective was this storm in bringing up this deep water.

  10. 110
    MARodger says:

    Wayne Davidson @108
    You say “For instance Hadley cell winds should be diminished (a la Lindzen)…
    Is this the Lindzen assertion that because of polar amplification, the temperature difference between equator & pole will diminish, and thus extreme weather will diminish?

    I have always found this somewhat nonsensical. It is akin to asserting that racing car drivers are safer driving faster because they complete the race more quickly and so have less opportunity to crash.
    In a warmer world, the reason the poles are warmer compared to the equator is surely entirely because of all that extra (more extreme) weather pouring polewards.

    Given the amount of cods wallop that Lindzen spouts, I consider that it is not good to use him to support a line of argument.

  11. 111
    prokaryotes says:

    Lesson: Arctic Sea Ice Decline

    The big picture – i just wonder about the paradox and that this is not just variability.

  12. 112
    John E. Pearson says:

    101 “we will have to go on what evidence we have, which does exist, as per the papers.”


  13. 113
    Unsettled Scientist says:

    > Given the amount of cods wallop that Lindzen spouts, I consider that it is not good to use him to support a line of argument.

    I’ve got a couple of issues with Lindzen, not the least of which that he will draw one picture in front of a scientific audience, then turn around and draw a different picture in front of an audience he thinks is incapable of calling him on it. It’s a character flaw that makes it so it doesn’t matter how good his science is, I cannot trust what he is saying. If his science is sound, it will be recognized by the community and I can ignore his presentations and non-peer reviewed writing.

  14. 114
    Jim Larsen says:

    110 MARodger said, “I have always found this somewhat nonsensical. It is akin to asserting that racing car drivers are safer driving faster because they complete the race more quickly and so have less opportunity to crash.”

    I think the analogy describes the effect well. Less temperature difference makes for a slower and so more wobbly jet stream. Another analogy would be riding a bike in a straight line. Go too slow and you’ll fall.

  15. 115
    Jim Larsen says:

    78 SA said, “It appears to me that “expert opinion” at the moment is stunned by the unexpected rapidity of Arctic sea ice decline.”

    Yeah, probably quite the moving target. That old phrase might need a bit of adjustment, “It appears to be far worse than we thought.”

  16. 116
    Lynn Vincentnathan says:

    Not sure how to respond to this topic. Does this mean Santa Claus won’t be bringing Xmas gifts much longer, or they’ll be all wet and soggy?

    RE “It’s worse than we thought.” I just posted to a blogger who raised the typical red herring re “and how many of the climate scientists’ predictions have panned out?” To which I replied, not many actually, because what they’ve been finding instead over and over again in the 22 years I’ve been following the issue of CC is “it’s worse than we thought,” “It’s much much worse than we thought.”

  17. 117

    #110 Rodger

    “In a warmer world, the reason the poles are warmer compared to the equator is surely entirely because of all that extra (more extreme) weather pouring polewards.”

    Not quite, Arctic permafrost ( a major player in Arctic climate) is weakening and retreating to the North,, the Arctic ocean sea ice is lesser expansive causing great Arctic Ocean warming. Even during recent Maximum extent, the lesser sea ice thickness has a significant impact (allowing more cyclones to penetrate the North Polar atmosphere). In effect the Arctic is becoming warmer, the Arctic Ocean is becoming a more important heat source over the long night. This summer showed what happens when there is far lesser ice with a warmer ocean.

    Although I am a great fan of criticizing Lindzen especially when he acts like a standup spokesperson for contrarian interests, he didn’t get that chair at MIT by being controversial, that came after.

    Imagine a world with the oceans having lesser sea surface temperature differences, the doldrums come to mind.

  18. 118
    Perk Earl says:

    Looks like the arctic ice extent melt is slowing down. The link above (from today – updated at exactly 5:00pm PST every day) shows it to be about 4750 million sq. kilometers, but yesterday was about 4800. During the recent storm the melt was around 200 thousand kilometers a day, then went back to about 100k a day (which is what it was previously averaging), but now seems to have slowed considerably. Even at 50 k drop a day the record will probably still be broken.

  19. 119
    ozajh says:

    William @ 109,

    Has any information surfaced whether or not the salinity of Arctic surface water increased following the storm of Aug6.

    Yes, very much so.

    The arctic-summer-storm-open-thread on Neven’s blog has some details and further links.

  20. 120
    wili says:

    Yes, there is something of a pause, but the latest DMI graph shows the melt rate (shrinking of extent) picking up again.

    (Thanks to George Phillies at Neven’s blog for the link.)

  21. 121

    New Arctic cyclone has formed north of Greenland. Satellite photos here (hit the page down key a few times to reach the post, please):

  22. 122
    Perk Earl says:

    Just as a follow up to my post yesterday (#118 with link to NOAA) the slower melt has continued into a 2nd day with approx. a 50k melt, down from yesterday’s 4750 million sq. kilometers to approx. 4700. So two days in a row of 50k melt (the new lower melt rate).

    Per this link: the ice extent minimum in 2007 was: On September 9, 2011 sea ice extent dropped to 4.33 million square kilometers (1.67 million square miles).

    From where we are now: 4700, and with an average melt per day of 50k, a new record would be set at 4300 million sq. K in 8 days, on Monday the 27th of August. Since the melt towards the end of the season slows, let’s say from Aug. 27th to Sept. 15th the melt averages 35k a day, would be 19 days x 35 = 665k, bringing the new record down to 3635.

    That was just an example, because the melt can occur on many different dates in Sept. and the average daily melt may be > or < than 35k.

    However, it's starting to look like we might get a final melt count down in the 3's, i.e. less than 4 million sq. kilometers. That in of itself would herald in a new threshold the MSM might sit up and take notice of, even if it was for one news cycle.

  23. 123
    Brian Dodge says:

    “Getting back to Derek’s original question, it cannot be answered, as historical extent of the floating sea ice cannot be determined by proxies.”

    Science disagrees. “These results are consistent with the northern Ellesmere Island record indicating an abrupt termination in driftwood stranding along most of the north coast (>250 km) after 5.5 ka due to the development of exceptionally thick, multi-year landfast ice (ice shelves) with possibly only short intervals of lesser ice since then (England et al., 2008). The growth of these ice shelves indicates very high ice concentrations in the adjacent Arctic Ocean since ca 5.5 ka, which apparently expanded and ice-locked Northeast Greenland coast by ca 3 ka.” And which will cease within a few decades.
    “On suborbital time scales, ice distributions varied in the Holocene, but no evidence exists for large, pan-Arctic fluctuations. Historical records indicate that Arctic sea-ice extent has been declining since the late 19th century. Although this decline was accompanied by multidecadal oscillations, the accelerated ice loss during the last several decades lead to conditions not documented in at least the last few thousand years. Taking together the magnitude, wide geographic distribution, and abruptness of this ice loss, it appears to be anomalous in comparison with climatic and hydrographic variability observed on submillennial time scales and longer-term insolation changes.”
    History of sea ice in the Arctic, Polyak et al. Quaternary Science Reviews 29 (2010) 1757–1778

  24. 124
    Alexandre says:

    I’ll bet on Sep 1st for the 2007 record low to be broken.

  25. 125
    Will MacKinnon says:

    Is there a nice brief comparison of the methodologies used by NSIDC to determine sea ice extent vs. the sources used by Cryosphere Today? With over a million square kilometer difference in their estimates and Cryosphere Today, today showing a new minimum it would be nice to understand how each is derived.

  26. 126

    “I’ll bet on Sep 1st for the 2007 record low to be broken.”

    Not with me… but let me know if you get takers…

  27. 127
    idunno says:

    Hi will,

    NSIDC measures extent, Cryosphere Today measures area. See here:

    CT area has now fallen to an all time low record:

  28. 128
    MARodger says:

    @Will MacKinnon @125
    The two measures of Arctic Sea Ice you ask about are very different, one called Extent the other Area. (NSIDC measure both but usually only mention Extent.) Area is as you would expect, the area of ocean covered with ice. Extent is the area of ocean that is covered with more than 15% ice (DMI use 30%.) and was adopted to make the measurements of melting ice flows easier.
    A graph of NSIDC Area & Extent is linked here (usually 2 clicks to ‘download your attachment’).

  29. 129
    HarryW says:

    Andy, saw your divx video on SkS: Great work!

    A suggestion; would it be possible to ‘slow it down,’ such that a person could see it unfold more slowly, and to be better able to tell the beginning date? I had to watch it a few times to figure out the start date.

    Keep up the good work!

  30. 130
    Andy Lee Robinson says:

    @HarryW @125
    Thanks Harry, I really intended it to be looped with VLC or mediaplayer, but youtube and other online video methods (excluding animated gifs) don’t really take looping into consideration.

    With my initial version, anyone could download and adapt the timings to fit any dialog as appropriate, though I can redo easily using existing frames. I’ll add a pause at the beginning to allow viewer to digest the scene, then animate more slowly by duplicating frames.

    It should be more publishable with Aug and Sept results when they are in, and easy to do – just another linux command with the new PIOMAS source data and an 8 hour wait for the results at 1080p.

  31. 131

    Look at sst’s all over the Arctic, Stretches the imagination:

    4 to 5 C above normal.

  32. 132
    derek says:

    #91, you asked why I am curious what we can deduce from the loss of Arctic ice? I am not trying to debate global warming as a reality, but am just trying to understand what can be inferred form sea ice, and get a feeling for the magnitude of the current drop compared to variations over a longer time span.

    Thanks for all those people that provide links on proxy reconstruction of Arctic Ice. I found these papers very interesting. Cheers.

  33. 133
    Perk Earl says:

    Found what appears to be a graph error on the NSDIC ice melt extent for 2007! The link for that graph is:

    If you put a ruler across from the bottom of the dotted 2007 line, it appears the ice melt in 07 reached 4200 million sq. kilometers. However, 2007’s melt record was actually not that low, it was 4330. Now look at the left hand side legend where it has the years 2012 over 2007. 2012’s legend position is arbitrary, however 2007’s dotted line is correctly located at 4330 (evidently purposefully done to mark that record melt point while also using it as a legend). Now put your ruler across from the legend and you will see the dotted line on the graph drops below that point to about 4200. That’s a false deviation of 130 thousand sq. kilometers (or about 2.3 days at current melt rate of 50k a day), making it look like the 2012 melt has further to go to reach 07’s melt than is actuzlly the case.

    2012 is at about 4550 and 2007 was 4330. In approx. 4 days the 07 record will be matched.

  34. 134
    Perk Earl says:

    Correction: (or about 2.6 days at current melt rate of 50k a day),

  35. 135
    L. Hamilton says:

    The DMI 30% extent index also reached a new low point today (dated Aug 20). The Uni Bremen 15% graph too is in record territory, although the UB team views their present data as provisional. Over at Neven’s folks are noting the records falling like dominoes one after another; it’s quite possible they all will in the next week or two.

  36. 136
    Jon says:

    @Perk Earl,

    This is off the cuff without checking the numbers myself but are you sure you aren’t being confused by the distinction between the lowest 5 day average extent NSIDC recorded in 2007 and the monthly average extent for September 2007, which is officially recorded as 4.30M at Naturally, the lowest daily value in the month is lower than the average for the month so I can’t see how the lowest daily value could have been 4.33M and the monthly average 4.30M.

  37. 137
    Michael Stefan says:

    Perk Earl, I think you are confusing the September 2007 monthly minimum extent with the daily record minimum, which was obviously lower; looking at the archives, NSIDC at the time put the 5 day record minimum at 4.13 million square kilometers and I doubt it was revised after the fact by that much:

  38. 138

    Probably should add that the North Hemisphere’s snow cover has dropped dramatically over the past few decades:

  39. 139
    Perk Earl says:

    Post #137, yes 4.13 is correct. I had found an archived article that was from Sept. 15th, 2007. Thanks for the correction.

  40. 140
    Hank Roberts says:

    Is there a shift toward a later date and a longer period of open water, along with the increase in maximum area melted, over the past decade or two?

  41. 141
    MARodger says:

    Tenney Naumer @138
    I’d reckon a link to the actual story might be more appropriate than that link to the “accepted wisdom” graphic (that graphic being the only bit you can’t blame me for). :-)).
    The Untold Drama of Northern Snow Cover now showing at Neven’s.

  42. 142
    Yves says:

    For anyone interested in the opening of Northwest passage I’d recommend the detailed maps from Canadian Ice Service (, en français aussi bien sûr (mais pourquoi pas également en inuktitut, c’est pas juste :-( ). They present composite images from Modis and Radarsat satellites. According to the images I browsed through, the opening seems imminent if not already done, though ground confirmations are necessary.
    From the ground, I’d recommend where several ships are attempting the passage. Quite interesting!

  43. 143
    Chris Dudley says:

    Looking at the JAXA graph, it appears that it usually takes about 40 days for the derivative of the sea ice extent to go from roughly constant and negative in the June-July decline to positive sometime in September. This year, the period of (roughly) constant negative derivative seems to have extended to the present. It will be intersting to see if that means that the sea ice extent minimum will come in October this year rather than September.

    The emergent seasonal structure in the sea ice volume anomaly plot may get more pronounced.

  44. 144
    Jim Larsen says:

    Actions speak louder than words.

    I’ve been saying for years that the argument is futile. Your equations VS their equations as judged by those who don’t understand equations…. Yeah, that’s gonna lead to a solution.

    But ice melts at 0C (as modified by salt).

  45. 145
    Lauri says:

    It is quite stunning to look at the MODIS rapid response LANCE pictures around the North Pole. I am surprised by how little fast ice appears to be left. Much of the ice north of 80 degrees is fragmented. Not like it would consist of melt ponds but, rather, big ice floats that crunch each other. This is only seen in the higher resolution pictures, such as

  46. 146
    Richard D says:

    Hi, out of interest, what’s the criteria for ice free arctic ocean, what if it mostly disappears (say within 5 – 10 years), for at least one day in summer, but small frozen areas remain around the edges, perhaps in sheltered spots ?

  47. 147
    Alexandre says:

    It was far faster than I would have betted for: JAXA Sea Ice extent record low is broken today…

  48. 148
    wili says:

    Richard D @ #146–over at Neven’s Arctic Ice blog, they seem to have settled on 1 million k^2 area as their definition of ‘virtually ice free’ Arctic Ocean, and we are getting perilously close to that this year.

  49. 149
    Hank Roberts says:

    > what’s the criteria for ice free arctic ocean

    Watch for the news bulletin:

    “Santa Claus lost at sea, presumed drowned along with entire family and workshop.”

  50. 150

    140 Hank “Is there a shift toward a later date and a longer period of open water, along with the increase in maximum area melted, over the past decade or two?”

    Between the Arctic Islands yess, not quite for the Arctic Ocean the refreeze is relatively fast but this has slowed down due to warmer sst’s, its the regular yearly latest contrarian trap, they fool themselves silly that the ice has recovered, but its an illusion they love to fantasize about. The biggest question is what are the impacts of thinner sea ice during the long night? The largest effect so far is the lessening of winter atmosphere build up, and more frequent penetration of cyclones from the South, a feedback loop causing the ice to be even thinner.