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  1. Hope the next IPCC report has a better section on the retreat of sea ice. It has already retreated faster than all models under all scenarios; obvious bias in the models. Also, the IPCC chart comparing models was a display of the average extent during the months of July, August and September. The implication being that there can’t be any sea ice during those months before the arctic can be said to be seasonally ice free arctic However, sea ice reaches it minimum in September with August and October the next lowest months.

    Looking at trends in sea ice volume, it’s apparent that the arctic will reach a minimum of zero within the next decade.

    Comment by Andrew — 1 Sep 2011 @ 8:10 AM

  2. I take back some of what I said last month. I really like what Didactylos and Sphaerica (Bob) did with a monochromatic graph keyed on year, last month that started here.

    http://www.realclimate.org/index.php/archives/2011/07/arctic-sea-ice-discussions/comment-page-3/#comment-211290

    My favorite color would be light-blue = more distant past and dark-blue = more recent, and maybe on offset color for the current year. I can’t make a pattern out of the color schemes used above.

    I used to hope that people would wake up when they saw the trend in ice melt (How can they reconcile a huge decline in ice with no real warming trend? Yeah, I know, not all people in denial say there is no warming, but that zombie keeps walking around.), but that hasn’t been the case.

    Comment by Chris G — 1 Sep 2011 @ 9:33 AM

  3. The 2011 graphs so far look to be tracking almost as low as the 2007 minimum for area and extent and the downward trend in volume is still clear. Another good picture at PIOMAS shows the daily volume trend in a format more comparable to the JAXA graphs. If the volume trend persists, it will take only one slightly warmer than average summer to break all records for minimum extent and area. With the current solar cycle still looking like peaking on the low side, this is not too surprising but we can’t rely on that to save us long term.

    #2 Chris G: we may only really “wake up and see the ice melt” at the peak of the next solar cycle if this one tops out lower than average as expected.

    Comment by Philip Machanick — 1 Sep 2011 @ 10:31 AM

  4. Jacobson: Soot’s the thing.

    “Soot emissions account for about 17 percent of global warming,….”

    “Jacobson says his calculations show controlling soot could reduce warming above parts of the Arctic Circle by almost 3 degrees Fahrenheit within 15 years, virtually erasing all of the warming that has occurred in the region during the last 100 years, a society release reported Wednesday.”

    That does not compute.

    Comment by Pete Dunkelberg — 1 Sep 2011 @ 10:31 AM

  5. There is also Bremen sea ice extent:
    http://iup.physik.uni-bremen.de:8084/amsr/ice_ext_n.png

    Comment by Pete Dunkelberg — 1 Sep 2011 @ 10:41 AM

  6. http://www.msnbc.msn.com/id/44353322/ns/us_news-environment/

    New photographs taken of a vast glacier in northern Greenland have revealed the astonishing rate of its breakup, with one scientist saying he was rendered “speechless.”

    In August 2010, part of the Petermann Glacier about four times the size of Manhattan island broke off , prompting a hearing in Congress.

    Researcher Alun Hubbard, of the Centre for Glaciology at Aberystwyth University, U.K., told msnbc.com by phone that another section, about twice the size of Manhattan, appeared close to breaking off.

    But when they returned in July this year, they found the ice had been melting so quickly — at an unexpected 16-and-a-half feet in two years — that some of the masts stuck into the glacier were no longer in position.

    Comment by floundericious — 1 Sep 2011 @ 10:44 AM

  7. MSNBC Article reporting that a second huge ice island is set to break off the Petermann Glacier

    Sorry if this is old news to you all!

    Comment by floundericious — 1 Sep 2011 @ 10:47 AM

  8. Can I ask for some help understanding the set of graphs? The first two appear to show not much in the way of trend at the peak ice but upwards of a 1/3 (!) loss in ice extent at the minima – yet 2007 may be a bit worse than 2011. However the trend line appears to show 2011 being significantly worse than all previous years including 2007? What am I missing?

    [Response: Different metrics. Arctic sea ice is not easily condensed to a single number, and each of the graphs show different aspects of the situation. The resolution of the apparent contradiction is that the ice is roughly equally spread out this year compared to 2007, but overall is thinner. I am not aware of any analysis that says that one metric is more indicative or predictive than another in any general sense. It's just part of the complexity. - gavin]

    Comment by JohnN — 1 Sep 2011 @ 11:35 AM

  9. I have reservations about the volume numbers and ice thickness models. The piomas version 2 model that was introduced this spring shows considerably higher thickness values. The navy, for example (http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictnnowcast.gif) reports two to three meter thick ice all around the north pole. Russian and American science vessels recently met at the pole and reported actual thickness of a meter or less.

    Given that we currently have ~3 million square km of ice it would have to average more than 2 meters thick to reach the current piomas volume of a bit over 6 thousand cubic km. Given the thin and fragmented ice the Healy went through on the way to the pole I personally find that average doubtful.

    Given the disagreement between volume models and real-world measurements – admittedly limited spatially – I’m left wondering what the actual volume is. I’m looking forward to cryosat results once they’re done with the calibration phase.

    Note that there’s no good reading on arctic ice. If the models are all right wrt volume the ice is declining alarmingly. If the real-world measurements are closer and volume has already declined to 4,000 cubic km or less then we’re in even more trouble.

    Comment by David Miller — 1 Sep 2011 @ 12:39 PM

  10. #8–To elaborate a bit on Gavin’s response, the top graph is “extent,” which means the total area of map gridboxes containing more than 15% ice.

    The next is “area,” which attempts to quantify the area within those grid boxes which is actually ice-covered.
    Area is thus always going to be smaller than extent-well, for any realistic case, anyway. And the two track fairly well in general, though ice can spread out, which can increase extent but not area, or the reverse.

    For these measures, variability does change throughout the year; as you noted, the biggest change is in the warm part of the year (though the biggest change in Arctic temperature is the trend in the winter.)

    The third graph is volume, but the difference is greater than that, because it’s also graphing anomalies, not just the values themselves. It’s a useful way to display things in that it eliminates the annual cycle, which is so evident in the other graphs. You can also graph area and extent that way (and I know just where to find a couple of graphs like that–when I’ve posted this comment, I’ll go and fetch the links.)

    You can read more about these matters, and many other related ones, too, here:

    http://nsidc.org/arcticseaicenews/
    http://nsidc.org/arcticseaicenews/

    Comment by Kevin McKinney — 1 Sep 2011 @ 1:39 PM

  11. Sorry for the double link in the previous. Here’s the promised links:

    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_N_min_to_date.png

    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_UBN_min_to_date.png

    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_VOL_min_to_date.png

    These bar graphs are all by L. Hamilton; be aware that they don’t all come from the same data source, so processing algorithms and therefor results may differ a little, apart from the fact that they are showing different metrics.

    They (and much, much else) can be found here:

    https://sites.google.com/site/arcticseaicegraphs/

    Comment by Kevin McKinney — 1 Sep 2011 @ 1:48 PM

  12. David Miller says:
    1 Sep 2011 at 12:39 PM

    Russian and American science vessels recently met at the pole and reported actual thickness of a meter or less.

    Can you direct us to a pointer on that? Over on Neven’s Arctic ice blog there’s speculation that ships visited the N Pole this year and didn’t gather that information. Sounds most unlikely that researchers on these ships would be so myopic.

    Comment by Doug Bostrom — 1 Sep 2011 @ 3:28 PM

  13. The Navy site says “system and web page are a demonstration and are not an operational product. NRL is providing the INFORMATION on an “as is” basis. NRL does not warrant or represent this INFORMATION is fit for any particular purpose ….”

    – I wonder if the report there showing ice thickness not as an average but as a navigation aid (as in, low hanging ice, don’t bang your submarine ….)

    Pure speculation. Perhaps someone knows.

    Comment by Hank Roberts — 1 Sep 2011 @ 3:36 PM

  14. The three bar graphs (annual 1-day minimum CT area, UB extent & PIOMAS volume 1972 or 1979-present) that Kevin McKinney linked above are being updated frequently while the melt season continues.

    They’re intentionally simple, losing that “complexity” Gavin alludes to, but pretty easy for anyone to follow.

    I should have a new graphic within a day or two at Neven’s blog, comparing the five main area & extent time series.

    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_N_min_to_date.png

    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_UBN_min_to_date.png

    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_VOL_min_to_date.png

    Comment by L. Hamilton — 1 Sep 2011 @ 5:47 PM

  15. Polarstern, not Healy (still on its way there)
    http://neven1.typepad.com/blog/2011/08/polarstern-reaches-north-pole.html

    Comment by Jathanon — 1 Sep 2011 @ 5:55 PM

  16. The latest data on NSIDC suggest that this year’s extent coud break the 2007 all time low. In any case, it will be very close. The Petermann glacier just lost a huge chunk of ice, according to blurb on Yahoo I just noticed. The comment thread was a pathetic display of ignorance, name calling and libertarian type ranting. Not very encouraging.

    Comment by Philippe Chantreau — 1 Sep 2011 @ 6:21 PM

  17. Thanks for bringing this forward; i was just checking to look for it after reading about the Greenland ice sheet depletion.

    Comment by spyder — 1 Sep 2011 @ 7:31 PM

  18. I do have one friend who is very much on the denialist bandwagon, and is a devoted fan of wattsupwiththat.com. I mentioned this issue about the thinning Arctic ice to him, and his reply was that the melting is being caused by “thousands and thousands of underwater volcanoes.” I have to admit, I hadn’t expected that reply – I thought he would just deny that any ice thinning was taking place. Intrigued, I pressed a little further, and asked if he thought there was an increase in the number of underwater volcanoes, and if so, why that might be. Again, he provided a sincere but entertaining response, saying that yes indeed, volcanoes were becoming increasingly active all over the world (he offered up the recent eruptions in Iceland as proof). The reason, he says, is that the planets are all lining up, a process that will come to a head in 2012, and cause the Yellowstone Super-volcano to erupt with disastrous results. He suggested I rent the video “2012″, a Hollywood blockbuster which until now I’ve managed to avoid watching:

    2012
    http://www.imdb.com/title/tt1190080/

    Well, there you go. We have a full explanation for the thinning Arctic ice, and it has absolutely nothing to do with CO2 emissions. And here I was needlessly worrying about AGW. Silly me.

    Comment by Candide — 1 Sep 2011 @ 8:38 PM

  19. #18–Well, then, “glitter and be gay!”

    Comment by Kevin McKinney — 1 Sep 2011 @ 10:06 PM

  20. If the ice were melting as a result of underwater volcanoes, then we would expect the oceans to be warming from the bottom up. But actual (non-Hollywood) data shows that the oceans are warming from the top down, i.e., the heat is coming from above, not from below.

    Don’t expect evidence to change your friend’s mind, however.

    Comment by KAP — 1 Sep 2011 @ 10:08 PM

  21. Well yes Candide, but those rapidly increasing volcano numbers are a worry!

    Comment by David Horton — 1 Sep 2011 @ 10:11 PM

  22. Candide – you friends needs medication – quickly. That is seriously detached from reality.

    [Response: I don't know. Is the idea of planetary alignments causes mass climate change in 2010 really so different than the idea that keeps popping up (e.g. J. Curry) that the increase in CO2 in the atmosphere might not actually be related to human activities? You start medicating the astrology buffs and you'll start medicating everyone. --eric]

    Comment by Phil Scadden — 2 Sep 2011 @ 12:08 AM

  23. #9 David Miller says …

    NAVO’s PIPS 3.0, aka ACNFS, over 15 years in the making, is still a POS IMHO.

    The end user is NIC, and the best use of NAVO’s model is for ice edge detection, it’s meant for operational use only, meaning navigation in open waters.

    Read their own calibration report here;

    http://www7320.nrlssc.navy.mil/hycomARC/prologue.html

    http://www7320.nrlssc.navy.mil/pubs/2010/posey1-2010.pdf

    It overpredicts ice thickness by over a meter when compared to USACE CRREL (I use to work at CRREL way back in 1975) buoy data.

    It overpredicts fly over data by about 0.4 meters (Note: Not much of this type of data to compare against, if you were to ask me).

    In total it isn’t much of an improvement over PIPS 2.0, sorry but, Navy 0 Army 1.

    Have you been to the PIPS 2.0 site lately?

    It’s offline, after twice predicting a POLE HOLE where none existed, and I saved all those daily GIFS (from their 2nd failed attempt), to make a nice animated GIF of that absurd model.

    Further, I’m building a collection MODIS imagery where PIPS 3.0 shows 5+ meter thick ice, but there are actually open leads and much scattered/broken up sea ice, 5+ meters my AZZ!

    NOTE: You can stop with the Goddard type talk, now there’s a real ******** if ever there was one.

    Comment by EFS_Junior — 2 Sep 2011 @ 12:14 AM

  24. #18 Candide says …

    2012? IMHO the worst movie ever made, it’s like Transformers One raised to the power of Transformers Two, itself raised to the power of Transformers Three, …

    See;

    http://en.wikipedia.org/wiki/Tetration

    Comment by EFS_Junior — 2 Sep 2011 @ 12:29 AM

  25. I think what JohnN is missing is that the bottom graph is for volume anomalies which takes the thickness of the ice into account. An area covered with 3 meters of ice has 3 times the volume of the same area covered with 1 meter of ice. There has been a significant loss of thicker multi-year ice over the past few years so the volume has dropped more than extent or area.

    Comment by Dave Werth — 2 Sep 2011 @ 12:46 AM

  26. 18 Candide: http://www.imdb.com/title/tt1190080/ says: “the crust of the earth is becoming unstable” like on Venus.
    Follow the links and the continents re-arrange themselves in a few hours. All because the planets are lining up.

    Yet your friend can’t believe CO2 is indirectly melting the Arctic ice? I need one of Joe Romm’s head clamps!

    Comment by Edward Greisch — 2 Sep 2011 @ 1:34 AM

  27. Comparing apples to apples (I think), the JAXA ASMR-E graph shows sea ice area as somewhat under 4 million km^2, but the cryosphere today graph shows sea ice area at 3.1 million km^2.

    Is there some way to reconcile those? Do they purport to measure the same thing?

    Comment by JimCA — 2 Sep 2011 @ 2:52 AM

  28. Just been looking at Prof Kevin Trenbeth latest findings..ie. for every 1 deg F. of ocean warming there is a 4% increase in water vapour in the atmosphere resulting in a 6-8% increase in rainfall. The spurious 6mm decrease in ocean height was the result of that riculously intense la-nina last year causing a hell of lot of rain to fall on land that is still perculating and meandering it’s way back to the oceans. Another study involving a tightly spaced convoy of 5 satellites 2 sec apart collecting data on cloud formation and extent, reports an over 50% decrease from the norm in arctic cloud cover. This is allowing even more sunlight to reach the remaining sea ice and cause accelerated warming not just from above but also below due the warming arctic ocean this is probably the ice area and extent graphs are so woeful this year and as I thought this year will most likely be the worst on record.
    One question I have that someone might know the answer to is….. due to 6-8% increase in rainfall over land could the change in river temp of all the thousands of swollen river waters emptying into the sea have any near future impact on the ocean’s temp. Logic says yes but I would like to have a rough idea as to what extent, whether it is negligible or yet another pos’ feedback system?

    Comment by Lawrence Coleman — 2 Sep 2011 @ 2:55 AM

  29. Lawrence Coleman @ 28, do you references for those statements?

    Comment by Pete Dunkelberg — 2 Sep 2011 @ 7:33 AM

  30. [Response: I don't know. Is the idea of planetary alignments causes mass climate change in 2010 really so different than the idea that keeps popping up (e.g. J. Curry) that the increase in CO2 in the atmosphere might not actually be related to human activities? You start medicating the astrology buffs and you'll start medicating everyone. --eric]

    Well, the friend only needs to be medicated for a year or so, to contain his anxiety about imminent death until such time as the fear can be, er, superannuated.

    Comment by Kevin McKinney — 2 Sep 2011 @ 7:35 AM

  31. “Comparing apples to apples (I think), the JAXA ASMR-E graph shows sea ice area as somewhat under 4 million km^2, but the cryosphere today graph shows sea ice area at 3.1 million km^2.

    Is there some way to reconcile those? Do they purport to measure the same thing?”

    Yes, this is indeed apples to oranges, and no, they don’t purport to measure the same thing. See my comment #10 above.

    Extent is probably becoming obsolete as a measure, in that it makes less sense as a metric the less cohesive (or the more minutely fragmented) the pack becomes. (Just my opinion.) But area is harder to measure, and of course backward-compatibility in data is highly desirable.

    Comment by Kevin McKinney — 2 Sep 2011 @ 7:43 AM

  32. #3 “If the volume trend persists, it will take only one slightly warmer than average summer to break all records for minimum extent and area.” by Philip Machanik.

    Not exactly. A ‘cool’ or ‘warm’ summer doesn’t have much meaning in that region. Summer 2007 was actually on average somewhat cooler than normal, even during the flash melts in that season: http://ocean.dmi.dk/arctic/meant80n.uk.php . This was also during solar dip and onset of a very strong La Niña.

    Sunshine and wind are more important factors. And most of the melting appears to happen from beneath, what with ever warmer waters lapping around and underneath the pack.

    I do agree with the gist of the message. The pack could disappear any summer now. Volume decrease is accelerating, catastrophe theory needs to be incorporated in modelling the phenomenon ( http://en.wikipedia.org/wiki/Catastrophe_theory ).

    [Response: Worth linking to this comment. To expand on that point though, the DMI plot shows a current weather forecast analysis compared to a re-analysis product using a different model. There is no guarantee (or even much expectation) that they are directly comparable in regions that are relatively poorly sampled (such as the Arctic). Thus trends derived from comparing the two (without making any allowances for differing biases) are not going to be very reliable. - gavin]

    Comment by cRR Kampen — 2 Sep 2011 @ 7:58 AM

  33. The NSIDC have an graph of total volume of ice and it down on 2007 as well.

    http://nsidc.org/images/arcticseaicenews/20110816_Figure5.png

    Joseph Romm often has articles stating that Arctic Sea Ice is in a death spiral.

    http://thinkprogress.org/romm/2011/07/08/262576/arctic-death-spiral-sea-ice-volume/

    The very last graph seem somewhat interesting. I believe that Richard Alley has stated that the models are running 100 years behind schedule and that warming in the Arctic is 4x faster than predicted.

    Comment by pete best — 2 Sep 2011 @ 8:27 AM

  34. On latest Envisat radar images sea ice concentration looks even worse compared to low resolution microwave echo images. Check out for example the North of the Laptev Sea.

    http://www.arctic.io/zoom/ouYS/0.45;0.3;1.37/Envisat-Radar-2011-09-02

    Here’s a close-up of the ‘ice pack’ bulging into East Siberian Sea waiting for compaction.

    http://www.arctic.io/zoom/y60y/0.45;0.46;2.77/East-Siberian-Sea-2011-09-01

    Comment by arcticio — 2 Sep 2011 @ 8:33 AM

  35. KAP (@20), the fact that the ocean would need to be warming from the bottom up is not a problem for the delusional, since they don’t even consider the water column between all these ‘new’ volcanoes and the ice. They simply assume that the warmth jumps straight from the volcanos directly to the ice.

    I’m not making this up: one of the more numerate denizens at WTFUWT actually calculated a ball park heat value emitted by these phantom volcanoes and declared that it would in fact be just enough to account for the 2007 melt…., except that he did not include the mass of the water column in his calculations.

    Comment by Jim Eager — 2 Sep 2011 @ 8:53 AM

  36. #31 — How is “sea ice area” for one apples and for the other oranges? What are they doing differently to measure ice area?

    Comment by JimCA — 2 Sep 2011 @ 8:57 AM

  37. #33 Envisat ASAR does not show ice concentration since the radar signal of water and ice can not easily be distinguished, in particular during summer.

    But yes, it is quite a mess! The colleagues on RV Polarstern are searching for suitable ice floes for drilling without much success http://www.geo.de/blog/geo/polarstern-blog/wissenschaft/schollensuche?LTblog=681ae33de5eb42054ef5d251977fe021

    Comment by Lars Kaleschke — 2 Sep 2011 @ 9:16 AM

  38. JimCA, where are getting confused by trying to compare?
    Cite/point to the site definition; they do differ.

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

    “Definition of sea-ice cover (extent and area)
    The area of sea-ice cover is often defined in two ways, i.e., sea-ice “extent” and sea-ice “area.” These multiple definitions of sea-ice cover may sometimes confuse data users…..”

    Wattsup explained it at his blog back in 2008; I don’t recall how well.

    Comment by Hank Roberts — 2 Sep 2011 @ 10:06 AM

  39. #36–Sorry, JimCA, I misread your original comment somehow. I was thinking one was for ‘extent.’

    However, you might imagine different area products as being, say Fuji apples versus Red Delicious (or something like that.) Significant differences still exist, even if they are all ‘apples.’

    One is the sensor used–IJIS uses the instrument on the Aqua satellite, which is why their data only goes back to 2002, while NSIDC uses data from a series of older instruments, suitably spliced together.

    Some products choose different resolutions, looking at 6.25 km2 grid boxes versus 12.5 k, and so on. This, too, can make a difference to the area result.

    Finally, the statistical presentation can make a difference. For example, the IJIS extent number is actually (I am told) a two-day moving average, whereas NSIDC extent presents a 5-day average. (This is all IIRC; I haven’t checked my memory on this.) So you’d expect NSIDC extent to be higher at this time of year, since it would be more affected by values ‘less far along’ in the melting process. (Haven’t checked if that’s the case just now, and of course other differences play into it, too.)

    If you want to specifically reconcile IJIS area and CT area, you’d want to search the ‘metadata’ that applies to each and see if you can infer what’s causing the difference you observe.

    It’s confusing, I know, and can be misrepresented by those naive or obfuscating folks who expect (or claim to expect) that these measurements should be an exact ‘truth.’ They are, as Gavin said, ‘metrics’–measurements–that are intended to give information about the ice. They are not the ice itself!

    One good thing about having all of these different metrics is the fact that, despite the differences of detail, they all show basically the same big picture. That gives us some additional reassurance that said “big picture” is not somehow the artifact of a particular way of measuring things.

    Comment by Kevin McKinney — 2 Sep 2011 @ 11:08 AM

  40. #38, Hank Roberts – Take a look at the RC article. There is a graph showing JAXA sea ice extent AND a different one showing sea ice area.

    JimCA is asking what the difference is between the JAXA data labelled ‘Sea Ice Area’ and the Cryosphere Today ‘Sea Ice Area’.

    ReCAPTCHA: Response rticatic

    Comment by Paul S — 2 Sep 2011 @ 11:36 AM

  41. Although the various ice measures disagree from day to day, their long-term agreement is striking. Here is a graph comparing five time series (NSIDC area & extent, UB extent, IJIS extent, CT area) of August means for 1972-2011.
    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_time_series_Aug.png

    Comment by L Hamilton — 2 Sep 2011 @ 1:19 PM

  42. Thanks for all the responses, everyone. I tried to be clear what I was asking, but should have been more explicit to avoid confusion.

    I think I see now how the difference might emerge, but then have to wonder if these folks talk to each other. Assuming there is a ground (so to speak) truth, it should be possible to perform spot checks on small areas to calibrate both, which presumably would reduce or even eliminate the discrepancy. But maybe that is easier said than done.

    Comment by JimCA — 2 Sep 2011 @ 1:43 PM

  43. Everyone, thank you for the responses. (And damn you captcha for eating the previous version of this message.) I tried to be clear in my question, but should have been more explicit to avoid confusion.

    I think I see how the discrepancy might arise, but then must wonder if those people talk to each other. It would seem to be straightforward to find small areas for which a ground (so to speak) truth can be found, then calibrate both series to that, in which case the discrepancy should mainly vanish. But maybe that is easier said than done.

    Comment by JimCA — 2 Sep 2011 @ 1:47 PM

  44. Any bets on another harsh winter for the CONUS this year? I’m betting on it happening again, caused by the lack of ice coverage in the Arctic.

    Comment by Rich Hendricks — 2 Sep 2011 @ 2:36 PM

  45. JimCA, they’re working on it. Examples:
    http://scholar.google.com/scholar?hl=en&q=arctic+sea+ice+satellite+area+estimation+pixel

    Your input could help:

    http://www.aip.org/fyi/2011/040.html

    “NASA Administrator Charles Bolden …. described problems confronting some earth satellite replacement programs, and starkly warned the committee “we are in dire straits as a nation when it comes to weather and climate prediction.” He was blunt in calling, as “dumb things” congressional attempts to defund a satellite program that would measure, among other data, shifting changes in the world’s climate. “I don’t do global warming, I do earth science,” he said emphatically.”

    Comment by Hank Roberts — 2 Sep 2011 @ 3:18 PM

  46. Why always JAXA and not IUE Bremen?

    Comment by Eli Rabett — 2 Sep 2011 @ 3:20 PM

  47. #41–”It would seem to be straightforward to find small areas for which a ground (so to speak) truth can be found, then calibrate both series to that, in which case the discrepancy should mainly vanish. But maybe that is easier said than done.”

    I think it would be a moving target, since the differences are effective at different times, or in different situations. So the discrepancies wouldn’t stay vanished for long (although they might conceivably “phase in and out.”) Plus the data sets would lose that backward compatibility I mentioned. (The jargon is that they would become internally “inhomogenous.”)

    #42–I wouldn’t bet on it myself–I think there’s more to NH winter weather conditions than just the ice cover–but neither would I be terribly surprised if it came about as you expect. There is, after all, some support for it in the literature.

    Comment by Kevin McKinney — 2 Sep 2011 @ 3:22 PM

  48. #42 Rich Hendricks,

    I don’t know this CONUS of which you speak. ;)

    But if you’re talking about the very cold winter periods we’ve been having in the Northern Hemisphere recently: I suggest you google for ‘Judah Cohen Siberian Snowfall’, link.

    I’m researching this at present for a post on my blog, should post in the next week or so. Cohen makes a fairly convincing case that anomalous Siberian snowcover has a pivotal role.

    Comment by Chris R — 2 Sep 2011 @ 3:27 PM

  49. Although the various ice measures disagree from day to day, their long-term agreement is striking. Here is a graph comparing five time series (NSIDC area & extent, UB extent, IJIS extent, CT area) of August means for 1972-2011.

    http://img.photobucket.com/albums/v224/Chiloe/Climate/sea_ice_time_series_Aug.png

    Comment by L Hamilton — 2 Sep 2011 @ 4:15 PM

  50. @ Candide — 1 Sep 2011 @ 8:38 PM Re sea ice melt and volcanoes

    see http://www.realclimate.org/?comments_popup=576#comment-90991 and http://www.realclimate.org/?comments_popup=576#comment-91077

    About the time I was posting that comment, I came across a skeptic who used a slightly different set of metrics, and calculated that a Vesuvius size eruption would melt an area of Arctic sea ice slightly larger than the ENTIRE state of Massachusetts!!!(assuming all the heat made its way through 4km of strongly stratified sea water) – then realized the relative scale of melt. The difference between average NSIDC minimum extent and current (or 2007) melt is ~2e6 km^2; the area of Massachusetts is 2.15e4 km^2. Yah think someone might have noticed 100 (give or take) Vesuvian scale eruptions, even if they were hidden beneath the Arctic ice?
    A mole! WHACK!!!

    Comment by Brian Dodge — 2 Sep 2011 @ 4:56 PM

  51. Chris R@46 or 3:27 pm

    Rutgers has a wonderful potpourri of satellite images which includes CONUS and GOES, as well as a variety of perspectives.
    http://synoptic.envsci.rutgers.edu/site/sat/sat.php

    I particularly enjoy the northern hemisphere water vapor animations which are centered on the north pole. It gives you a picture of how earth’s circulation:
    http://synoptic.envsci.rutgers.edu/site/sat/sat.php?sat=nhem&url=../imgs/wv_nhem_anim.gif

    I’d love to understand the physics of all this, but as an artist I find it ravishing, and at times it even helps me understand at the level of my necessary travels to care for my family, going back and forth from Boston to New Jersey (near Princeton) which often involves crossing the Jet Stream.

    Comment by Susan Anderson — 2 Sep 2011 @ 5:10 PM

  52. Neven links to other sites that update sea ice area graphs daily, here:
    http://neven1.typepad.com/blog/2011/08/area-graphs-3-million-km2-mark-passed.html

    “There are some other SIA graphs that are updated on a daily basis, such as the one by Arctic ROOS which uses SSM/I data provided by NERSC …

    There are some differences in the details of course, which is to be expected as different sensors and algorithms are used to record and process the data …”

    Comment by Hank Roberts — 2 Sep 2011 @ 7:17 PM

  53. A bit off topic – I can’t see how melting sea ice can cause earthquakes but can someone comment on:

    There were more earthquake­s at the end of the last ice-age as the Earth responded to the weight of the ice being removed. Now climate change is possibly taking 300 billion tonnes of ice off Greenland and 200 billion tonnes off Antarctica each year:

    http://www­.indianexp­ress.com/n­ews/antarc­tica-risin­g-by-5-mil­limetres-a­-year/8256­17/

    Look at the graph of increasing earthquake­s since the 1970s:

    http://www­.earth.web­ecs.co.uk/

    Perhaps some earthquake­s are climate related.

    Comment by Geoff Beacon — 3 Sep 2011 @ 4:05 AM

  54. @Lars Kaleschke

    The signature of melting ponds on Envisat’s radar images is eventually inaccessible to algorithms, but the human eye can easily recognize the flaked pattern of a low concentrated ice pack.

    So, here again the radar zoom one day later:

    http://www.arctic.io/zoom/qIMt/0.45;0.3;1.37/Envisat-Radar-2011-09-03

    not all swaths are updated…

    It is a shame that an instrument flying on a polar orbit, having a resolution of 30 meters and the ability to look through clouds is not used to its full extent to document the vanish of one of Earth’s most popular features visible from the moon with a naked eye.

    Comment by arcticio — 3 Sep 2011 @ 7:21 AM

  55. The thing about ice thickness and ice volume is that there are not nearly enough in situ observations of thickness (meaning man with ruler drilling a hole and taking a direct measurements. So I am more inclined to believe the statements from the scientists at the North Pole; the Russians maintain an ice camp there. (I know they are true because they are using CRREL buoys and I am the data manager for that project. To be clear, there is only one buoy there, but the Russians are making measurements of sea ice thix using other techniques.)

    Submarine tracks only measure the sail of the ice, maybe the draft, but there are not a lot of tracks (at least not enough declassified tracks) to make any broad statement.

    Ice draft (the thickness of ice from the ocean surface downward, about 90% of ice thickness) measured by satellite or
    aircraft haven’t been fully validated over the whole Arctic to the point where the error bars are satisfactory. Moreover, models such as PIOMAS haven’t been fully validated against ice area, ice extent, and ice draft.

    It gets worse. Data such as NCEP comes from the inclusion of weather station data, but those are all on the coast or inland. Not over the ocean where we need them.

    Don’t get me wrong. We’re losing ice extent and ice area, and using the buoy and manned ice camp data it’s clear we’re losing ice thickness. Hence, the volume is decreasing. But PIOMAS and other models have huge error bars on them. My point is that you can’t really use the numbers with any certainty to say we’ve lost, e.g., 43% per cent of the volume since 1979., or that the volume today is what the model says it is. You can say qualitatively that volume is decreasing, and you can say the models or ensembles agree on the trend. But filling in an actual number for volume? We’re not there yet.

    But ice is never uniform, it is a patchwork of floes and ridges of various thicknesses and also leads (open water or very thin ice). Even on a scale of 500 meters, there can be a great deal of variability.

    Comment by todd arbetter — 3 Sep 2011 @ 9:33 AM

  56. Sorry, the last paragraph of my post is non-sequitur to the rest of my point. There was another statement I wanted to make about ice thickness distribution. Since the ice is variable even at local scales, the footprint of the aircraft or satellite measurement is going to give you a mean thickness, mean area, and/or mean extent. PIOMAS and other models have to get that correct too. And the guys in the ice camp would have a lot of work to do to get a representative sampling of just their local area.

    The models need to get past conditions right before we can look at future conditions quantitatively. And understanding the model’s sensitivity to changes in forcing is key. Forcing will have errors too. If a temperature is off by half a degree, that could have a huge impact. Caveat Emptor.

    Comment by todd arbetter — 3 Sep 2011 @ 9:45 AM

  57. #49 Susan Anderson,

    So I presume CONUS stands for CONtiguous US.

    Rutgers is also the home of the snowlab, with snow data over various timescales and periods.
    http://climate.rutgers.edu/snowcover/
    Northern Hemisphere daily should be useful for those watching for Siberian snow cover this winter.

    #53 Todd Arbeter,

    Thanks for your clarification and for the work of you and your colleagues – from all nations and institutions. IMO you’re working in the most exciting area of science today.

    Comment by Chris R — 3 Sep 2011 @ 1:06 PM

  58. I think one of the most important and interesting things about this year is that it proves that 2007 was not just a outlier event, caused by some very unique set of events unrelated to general global climate change. Many climate change skeptics were keen to celebrate the “recovery” of the sea ice in 2008 and 2009 after the steep summer decline of 2007. Then along came 2010, which did not continue that “recovery”, and now we have 2011, which is challenging 2007 for record lows.

    Why is this important? It’s important because it completely shatters any notion of a “recovery”, and skeptics can only move on to other “proofs” for their skeptical positions. But 2011 is scientifically important because 2007 and 2011 had such different melt dynamics, and it shows that the total enthalpy of the system must be considered when looking at melt dynamics. Wind, waves, water temperature, ocean current speed, air temperature, atmospheric pressure, salinity, early season melt and open water, etc. are all part of the enthalpy of the system and the mixture or combination of them will determine each season’s melt dynamics. 2011 proves, conclusively that 2007 was not an outlier, even though each had a different melt dynamic. More importantly, it proves that the total enthalpy of the system is trending in the direction the GCM’s would indicate (i.e. upward). Based on the long-term trend line, which has deflected significantly downward off the 30-year trend line in the past 5 years, there is a high degree of probability that at least one of the years between 2012-2015 will significantly dip below 2007 & 2011′s low marks in area, extent, and volume.

    Comment by R. Gates — 3 Sep 2011 @ 1:25 PM

  59. Geoff Beacon #51, re: historical earthquake graph:

    Evaluate the reliability of your sources. Check out whose site that is—it’s a telecoms consultancy, not a seismology department. Look at the interpretation beneath the graph, particularly where the science talk starts segueing into Bible quotes and stuff gets a little weird.

    Read the fine print. Weird or not, that page does caution, rightly, that the graph includes small quakes which we’ve got better at detecting. In other words, the graph doesn’t show more quakes happening, it shows more quakes being recorded.

    They go on to argue, plausibly I think, that one can deal with the bias by limiting the discussion to large quakes (magnitude 7 and up). The obvious next step would be to do that to the USGS NEIC data I presume was used for the graph, but instead it looks like they switch to a USGS list of “selected earthquakes of general historic interest”. We’ve recently been over why this looks like a bad idea (http://www.realclimate.org/?comments_popup=7897, see comments by Prokaryotes, Piotr and myself, starting at #100).

    Comment by CM — 3 Sep 2011 @ 2:54 PM

  60. Geoff Beacon @ #53

    I do not know of any relation between sea ice loss and earthquake activity, but there is a body of work to do with the loss of land based glacial ice correlating with geomorphic response (Volcanoes, eathquakes ect).

    One place to start. http://dash.harvard.edu/bitstream/handle/1/3659701/Huybers_FeedbackDeglaciation.pdf?sequence=1

    I believe it was Kevin Hall who first hypothesised the relationship in 1982

    Comment by Tony O'Brien — 3 Sep 2011 @ 9:34 PM

  61. >earthquake

    Hm. If each earthquake frees up a burst of available hydrogen for the deep biosphere organisms that live on it,
    http://www.google.com/search?q=hydrogen+deep+biosphere
    that should be a selection pressure favoring forms that change their environment to favor more earthquakes, given sufficient time.

    Comment by Hank Roberts — 3 Sep 2011 @ 10:12 PM

  62. This has been an interesting year for the sea ice with it rocketing down from the winter highs then running into a cool/normal August. looks like a mix of records, near records and 2nd places for sea ice extent, area and volume.

    I think the reports from direct observations indicate things areworse than the numbers can show us.

    Update: http://aperfectstormcometh.blogspot.com/2011/09/current-state-of-arctic-sea-ice-arctic.html

    Comment by ccpo — 3 Sep 2011 @ 10:21 PM

  63. #32
    You’re trying to compare T1279 ECMWF to ERA40 baseline. It’s very bad idea.

    Comment by p — 4 Sep 2011 @ 5:35 AM

  64. #32
    You’re trying to compare ECMWF T1279 to ERA40 baseline (DMI charts) – it’s a very bad idea.

    Comment by p — 4 Sep 2011 @ 5:37 AM

  65. Geoff Beacon,
    One must distinguish between loss of sea ice and loss of land ice. Loss of land ice changes the weight over a given point of land. The crust adjusts isostatically as a result. The only way you could see an effect due to sea ice loss would be if it were sufficiently large to change the geoid of the planet.

    Comment by Ray Ladbury — 4 Sep 2011 @ 6:07 AM

  66. CM @59

    Thanks.

    I’m glad I missed the discussion between Prokaryotes, Piotr and yourself at the time – it looked very intense.
    It’s a pity that the link to Climate Progress no longer works.

    I take your point about the climate science amateurs of webecs.co.uk but I’m rather more sceptical of professional climate scientists than most of you – and modestly sceptical of professional scientists in general. (see e.g. Food: Scientists vs amateurs, http://www.brusselsblog.co.uk/?p=250)

    I do have respect for nearly all the scientists in climate related fields but they are under pressure – the need to publish, the need not to be wrong, they need funding and they must wish for less abuse. Thus they are sometimes unreliable sources.

    Superficially the example of the USGS, does not change my outlook. They make the statement

    We continue to be asked by many people throughout the world if earthquakes are on the increase. Although it may seem that we are having more earthquakes, earthquakes of magnitude 7.0 or greater have remained fairly constant.

    http://earthquake.usgs.gov/learn/topics/increase_in_earthquakes.php

    … but on a related page give data that shows there is an increase.
    http://earthquake.usgs.gov/earthquakes/eqarchives/year/graphs.php

    Perhaps there is small print somewhere that resolves this.

    But on the question of sea ice, my experience of climate scientists has found them behind the curve and not just the ones mentioned in my last year’s piece, Fast and Super-fast – Disappearing Arctic sea ice, http://www.brusselsblog.co.uk/?p=45.

    I will do some more checking on a recent piece I wrote that contains a quote on the climate models that are being lined up for use in the IPCC AR5 process. This says

    four years ago the model teams decided not to include the permafrost carbon feedback
    in their IPCC AR5 projections due to the lack of data. We are making great progress, but the current round of simulations to support the IPCC AR5 do not include the permafrost carbon feedback. Nevertheless, we know enough now to recommend solid action.

    Is this still true?

    Will it too be lost in the small print that politicians and government departments can ignore ?

    Comment by Geoff Beacon — 4 Sep 2011 @ 9:58 AM

  67. Tony O’Brien @60. Thanks that looks very interesting.

    Hank Roberts @61. That’s too deep for me.

    Ray Ladbury @64. Yes of course.

    Comment by Geoff Beacon — 4 Sep 2011 @ 10:07 AM

  68. Thank you for this post and web site. The trend in the minimum sea ice areas over the last decade is unsettling. Mean while at the linked-in AGU site they are still debating whether sea level is rising or falling. Your site is a great resource. Keep it up.

    Comment by Dr. Geophysics — 4 Sep 2011 @ 10:33 AM

  69. Geoff Beacon,
    I’m sorry, but I can see no basis for you distrust of scientists than ignorance of how scientists work, and to move from that to distrust of the science–a product of tens of thousands of dedicated scientists with competing interests, pet theories, etc…. well, that is sheer folly.

    Geoff, science works. Why not learn why it does?

    Comment by Ray Ladbury — 4 Sep 2011 @ 12:08 PM

  70. Ray Ladbury @68

    “Science works”. What does that mean?

    Which model/methodology of “Science” are you following?

    Carnap, Popper, Kuhn, Feyerabend, Braithwaite, Quine, Lakatos, Bridgeman or my favourite Post?

    Comment by Geoff Beacon — 4 Sep 2011 @ 2:01 PM

  71. Geoff Beacon, those USGS graphs do not seem capable of showing the “increase” you claim. The available dataset is much larger than that.

    If you look at magnitude 8.0 and greater, there are an average of about 8ish per decade for the last century. The 1990s had 6, the 2000s had 13 – hence the non-existent “trend” you see. It’s just one decade below average, and one decade above average.

    We can be fairly confident in the data about major earthquakes going back a century, but, obviously, smaller earthquakes were not so well recorded in the past.

    Comment by Didactylos — 4 Sep 2011 @ 2:19 PM

  72. Does it strike anyone else that the PIOMAS ice volume graph no longer fits a linear model? How consistently does it have to be beyond two standard deviations for it to be clear that what is going on is not linear?

    Comment by wili — 4 Sep 2011 @ 2:19 PM

  73. Ray Ladbury @68

    My previous post was a bit petulant. Sorry.

    Comment by Geoff Beacon — 4 Sep 2011 @ 2:21 PM

  74. wili: I think the question is: when does another model perform better, and how can it be justified?

    The linear model is conservative. I don’t think anyone is claiming it to be predictive – not the “cycles” optimists, not the doom and gloom “plummet” types, and not the rest of us reality-based types, either. The best expert opinion still favours an accelerate-decelerate model, as far as I know.

    Comment by Didactylos — 4 Sep 2011 @ 4:22 PM

  75. Geoff #65,

    I’m a total amateur, so trust me! :-) (That’s not something you want to hear from your pilot. Or your brain surgeon. Is it?)

    I don’t want to go on about quakes on a sea ice thread, so I’ll stop after this. But I’ve looked at the USGS page you linked to and I’ve also downloaded a longer worldwide record of big quakes (magnitude 7.0 or above, 1973–2010). I’d describe it as a steep decline from the mid-1970s to 1989, followed by a sudden step change to a high plateau since 1990, and a big outlier in 2010, with lots of noise in between. I get a linear trend of nearly two quakes per decade since 1980 (seemingly highly significant, though more modestly so if the 2010 outlier is excluded, and I haven’t adjusted for auto-correlation). In the full record since 1973, though, the trend is barely one quake per decade, and not significant. Perhaps this explains the conflicting impressions you got on the USGS pages.

    The record is noisy, confusing, possibly incomplete, and a cherry-picker’s delight, so you really should listen to what the professionals say. Not to me. (And certainly not to the webecs page with sensational claims like the “six-fold increase” they claim under “trends since 1986″—on inspection, it turns out to be more of a one-sixth increase!)

    Comment by CM — 4 Sep 2011 @ 4:45 PM

  76. Geoff Beacon;

    I am concerned that the insidious notion still gets introduced that climate scientists are, (because of the pressure of needing funding and grants), likely to shade their results. Why is this not raised as an issue for all other fields of science, many of which are more profoundly dependent upon these monies than climate science? Don’t you find it odd that only this particular batch of researchers gets singled out? I do. In fact, I’m sorry to say that this particular ‘qualm’ that keeps popping up seems more a tactic than a genuine opinion. If you have evidence that proves this phenomenon, then by all means present it. And, while you do, add any and all similar studies and results viz all other scientific disciplines so that we may compare. I am unaware, probably due to my being raised in Kansas, of any propensity for the discipline of climate science towards waffling on data.

    Comment by greyfox — 4 Sep 2011 @ 7:28 PM

  77. Re: Geoff Beacon:”…take your point about the climate science amateurs of webecs.co.uk but I’m rather more sceptical of professional climate scientists than most of you – and modestly sceptical of professional scientists in general. (see e.g. Food: Scientists vs amateurs, http://www.brusselsblog.co.uk/?p=250)

    I do have respect for nearly all the scientists in climate related fields but they are under pressure – the need to publish, the need not to be wrong, they need funding and they must wish for less abuse. Thus they are sometimes unreliable sources.”‘

    Pardon me for saying so, but why would climate scientists be any different from, say, anthropologists, or astrophysicists, or…
    The way this particular subject keeps getting introduced produces a whiff of a variant of that old tried and true (but false) debate tactic, ‘the complex question’.
    You reversed the order but have the same end. The fact that this method of attacking the veracity of climate scientists keeps showing up, sans any proof or corollary evidence about other scientific disciplines, gives me a rather strong sense of being, (again, my pardon) rather deliberately disingenuous. Had you somehow come to this conclusion independently by virtue of some overt, widely known evidence, and had access to similar studies about all the varied scientific disciplines, I would be inclined to at least listen. However, there aren’t any that I am aware of…including the so-called climate-gate, which has been exonerated by several different official sources. Is there something you know that I don’t (and, being from Kansas, I might just be a tad slow) that you could share? If I have been rash, I will gladly apologize.

    Comment by greyfox — 4 Sep 2011 @ 7:52 PM

  78. Didactylos @70

    What I counted was the number of earthquakes in 10 year bins ending in 1991, 2001 and 2011. I got this from their figures (with no adjustment for the incomplete year 2011).

    For 8 to 8.9 earthquakes: 3, 8, 13

    For 7 to 7.9 earthquakes: 109, 142, 136

    For 6 to 6.9 earthquakes: 1102, 1518, 1632

    It looks like a plausible indicator for increased earthquakes to me.

    However I now note the USGS does say

    According to long-term records (since about 1900), we expect about 17 major earthquakes (7.0 – 7.9) and one great earthquake (8.0 or above) in any given year.

    My (late night) calculations give 0.8 “great earthquakes” per year over the past 30 years and 12.9 earthquakes per year for “major earthquakes”. The “17 major earthquakes in any given year” seems very high compared to the 12.9 average I get for the past 30 years. Perhaps they are cherry picking years?

    As a fig leaf to the current topic would a cheap an cheerful proxy for the loss of mass from the Greenland and Antarctic glaciers be the change in sea-ice volume. But perhaps someone has done some proper work on examining the loss of actual mass and seismic activity.

    P.S. How many earthquakes did the Three Gorges Dam create?

    Comment by Geoff Beacon — 4 Sep 2011 @ 8:19 PM

  79. CM @74

    Thanks. Just noticed your post.

    But we should be sceptical of “the experts”. Several got sea-ice wrong and I’ve had years of assurances on methane feedbacks … Let’s hope that Russian trip does not find anything too worrying.

    Comment by Geoff Beacon — 4 Sep 2011 @ 8:37 PM

  80. Since the ‘e’ word is being bandied about, please consider taking a look at a nicely articulated piece from NYT on “The Exterts and Global Warming”:

    http://opinionator.blogs.nytimes.com/2011/07/12/on-experts-and-global-warming/

    And it sounds as if there was already something pretty darn worrying and ‘dramatic’ that all those scientists had to be hustled up there ‘on short notice.’

    (recaptcha: neoclassic usmini)

    Comment by wili — 4 Sep 2011 @ 10:57 PM

  81. greyfox @75

    Pardon me for saying so, but why would climate scientists be any different from, say, anthropologists, or astrophysicists, or…

    I would trust anthropologists, or astrophysicists more because they are not under such commercially driven political pressure. Climate scientists are pretty good – they come above bio-chemists and way above drug-scientists.

    As if to prove my point the use of the hypenated word had caught the spam filter.

    Comment by Geoff Beacon — 5 Sep 2011 @ 2:31 AM

  82. Geoff Beacon: scientists on the whole tend to be very careful about making claims without evidence. One reason for this is that other scientists are generally very quick to criticise claims that are insupportable. This does create a bias: anything that may seem very alarming takes a long time to scientists generally to acknowledge. Example: James Hansen for some years has been warning that the geological record shows multiple metres per century sea level rise is possible. Despite this the IPCC’s 2007 report left out the contributions to sea level rise of land-based ice melts because the numbers were too uncertain. More recently research supports Hansen’s view. Given that more than a metre of sea level rise by the turn of the century would have massive economic consequences, if climate scientists really were labouring under the pressures you describe, they would be talking this up rather than developing a case slowly and patiently over many years.

    Comment by Philip Machanick — 5 Sep 2011 @ 3:07 AM

  83. Geoff,

    One last OT comment just for completeness’ sake: I think you can disregard my earlier caveat about auto-correlation. As for quakes over 8.0 that you mentioned, the 1973–2010 trend is up, but it’s significant only because of a high 2007 outlier. Buried somewhere in the June thread I think is a reference to some expert commenting in this vein, that it’s hard to discern any trends but some argue for a rise in the very biggest quakes. My layman’s guess about all this is that it’s plausible for anthropogenic ice-sheet melting to affect earthquake activity, but way too early for it to show up in this record.

    I’ll shut up now, but I’d welcome corrections to any of the above, as my ignorance of statistics is only rivaled by my ignorance of seismology.

    Comment by CM — 5 Sep 2011 @ 3:21 AM

  84. Geoff Beacon, allow me to introduce you to Mr. Poisson. The “trends” you report are not significant. You can demonstrate this to yourself by putting together a toy monte carlo (even Excel will do), running 10000 events and seeing how often you get a trend as significant as the one you are touting.

    Moreover, if there were a significant effect, we would expect it to manifest nearest where the mass changes are greatest. It doesn’t.

    Where we do see an effect is in small quakes near the places of large glacial melt as the ground isostatically adjusts.

    Also, the melting of sea ice and of glaciers are very different processes. I doubt they would correlate exceptionally well.

    Comment by Ray Ladbury — 5 Sep 2011 @ 6:56 AM

  85. Geoff,

    This is OT, but I found this comment of yours disconcerting and important:

    I do have respect for nearly all the scientists in climate related fields but they are under pressure – the need to publish, the need not to be wrong, they need funding and they must wish for less abuse. Thus they are sometimes unreliable sources.

    Since this site is actually run by climate scientists, I’d be curious about their responses to these “accusations,” that is, how influenced do they feel about your purported pressures, or rather, how much greater are these pressures on them than any other scientists at any other point in history. How are they different?

    In particular, I think the funding reference is a favorite WUWT style red herring.

    You later say:

    I would trust anthropologists, or astrophysicists more because they are not under such commercially driven political pressure.

    Same thing. Exactly what commercially driven pressure to you think climate scientists endure? Again, this sounds like a Wattsian or Moncktonian confabulation.

    I’d be curious to see how Eric, Ray Pierre and others would respond to this rather flippant charge.

    Comment by Sphaerica (Bob) — 5 Sep 2011 @ 10:09 AM

  86. Just to stir things up a little, I believe Peirs Corbyn can now predict quite accurately when (& where ?) large earthquakes occur as well as standard weather and record storms.

    I don’t believe him a bit – but he has good following in the AGW denialati because he is one himself. (Oh, & Geoff B, Corbyn is a well qualified astrophysicist I believe. Still trust him?).

    Comment by Clippo (UK) — 5 Sep 2011 @ 10:35 AM

  87. Geoff B, you really should read these posts by a climate scientist on funding.

    * Taking the Money for Grant(ed) – Part I
    * Taking the Money for Grant(ed) – Part II

    Comment by J Bowers — 5 Sep 2011 @ 11:32 AM

  88. 85, J Bowers,

    Awesome posts. Thank you.

    Comment by Sphaerica (Bob) — 5 Sep 2011 @ 12:05 PM

  89. Geoff says:

    I would trust anthropologists, or astrophysicists more because they are not under such commercially driven political pressure. Climate scientists are pretty good – they come above bio-chemists and way above drug-scientists.

    Lets try analyzing that statement….

    I would trust anthropologists, or astrophysicists more

    OK, Geoff likes these scientists better. Lets see why….

    … because they are not under such commercially driven political pressure.

    Commercially driven political pressure? Surely you jest. I understand commercially driven pressure by the likes of CEI, AEI, and all the other think tanks funded by fossil interests. I understand political pressure in some settings, but don’t see it in climate science. A primary reason for that is the influence on the government by commercial interests. See, for example, the Bush’s attempted muzzling of Hansen for “political pressure”.

    The union of these two subsets is extremely small in general, and definitely does not favor climate scientists.

    … Climate scientists are pretty good – they come above bio-chemists and way above drug-scientists.

    So after casting aspersion on the motives of climate scientists Geoff wants to seem reasonable so throws out a back-handed compliment.

    Geoff, if you want to convince me you’ll need some evidence. What I see is a theory (increased GHG result in higher temperatures) being confirmed by many lines of directly observable evidence. I see a lot of dedicated scientists working for peanuts under very unpleasant conditions. To accuse climate scientists of pandering for grants so they can take vacations in exotic locales like, say, antarctica, is just silly.

    Comment by David Miller — 5 Sep 2011 @ 12:56 PM

  90. Re: Geoff.

    May I apply the KISS principle? Geoff, where does your doubt of climate science, as opposed to your trust of all other areas of science, come from?

    Does it come from myriad research projects leading to large doubts about the viability of the science, vs. co-reinforcing, reproducible studies supporting what our naked eyes can see?

    No.

    Does it come from observations contradicting research, or vice-versa?

    No.

    Does it come from corruption trials showing climate scientists stealing money from us?

    No.

    Does it come from credible accusations of selling out to renewable energy companies?

    No. (Though there is ample history – not accusations, but history – of climate deniers taking money from the FF industry, among others, which doesn’t seem to bother your sort in the least.)

    Do we see massive avoidance of issues brought up by deniers?

    No. We see study after study refuting the poor science of denialists, though.

    Naomi Oreskes found years ago that exactly zero studies she reviewed to determine the balance of the climate debate in the mid-’90s supported a primary non-anthropogenic cause of warming. Since here study, I know of no paper that challenges this 1,000 – 0 finding.

    If denialists had something to say about climate, don’t you think it would be wisest for them to prove it scientifically?

    KISS it.

    Comment by ccpo — 5 Sep 2011 @ 3:03 PM

  91. Thank you to all.

    I would like to point out that I am not a climate change denier as some of the responses indicate. I think the situation is almost certainly worse than the picture that the official science appears to paint. (Isn’t that what this thread is about?) I say “appears” because I understand that there is small print in the various reports that is missed or deliberately ignored by main stream media and politicians and government departments.

    The pressure on climate scientists makes some reluctant to express opinions that are well judged and based on facts. There is self-censorship.

    I believe we have a problem that with climate scientists who won’t say what they believe unless they have a very strong chance of being right because of the chance that they will be wrong and damage their careers.

    At a time when it appears that much of official climate science has been found to be underestimating the dangers ahead, there is also the other problem: admitting previous inadequacies also damages careers.

    Another problem is that some climate scientists make judgments about what is possible in politics and adjust what they have to say to meet what they feel are political realities.

    One of the UK’s leading climate science journalists told me “They knew but they didn’t tell us”.

    I agree.

    It’s true that most climate scientists tell us climate change is happening.

    But they don’t tell us how bad it is.

    Comment by Geoff Beacon — 5 Sep 2011 @ 7:58 PM

  92. You’re talking aboutopinions Geoff, opinions are not science – they may be based on facts, but they are still opinions, not themselves verifiable facts. Science is about reproducible numbers, not beliefs, and certainly not about “political realities”. You need to be complaining about your politicians not listening to the climate scientists, not about what the scientists are very clearly saying.

    Comment by flxible — 5 Sep 2011 @ 8:50 PM

  93. Philip Machanick @82

    This does create a bias: anything that may seem very alarming takes a long time to scientists generally to acknowledge

    I agree.

    CM @83

    My layman’s guess about all this is that it’s plausible for anthropogenic ice-sheet melting to affect earthquake activity, but way too early for it to show up in this record.

    Perhaps Intrade can help quantify our guesses. What odds would you take?

    Ray Ladbury @84

    Moreover, if there were a significant effect, we would expect it to manifest nearest where the mass changes are greatest. It doesn’t.

    The mass change is moving mass from the ice-caps (and surrounding ocean due to the gravitational effect). I think the mass is moved to the equator.

    Sphaerica (Bob) @85

    Exactly what commercially driven pressure to you think climate scientists endure?

    Ask Phil Jones or Michael Mann.

    Clippo (UK) @86

    You’re cherry picking.

    J. Bowers @87

    I agree with Sphaerica (Bob) @88 . Awesome post. But what’s that to do with me.

    David Miller @89

    Geoff, if you want to convince me you’ll need some evidence.

    If my previous post gets through moderation you will see it’s anecdotal with few specifics.
    I try to limit my “Dr. X was wrong” comments.

    To accuse climate scientists of pandering for grants so they can take vacations in exotic locales like, say, antarctica, is just silly..

    Who accused whom?

    ccpo @90

    Geoff, where does your doubt of climate science…come from?

    Experience.
    As this thread is pointing out, climate change is worse than we have been told.

    as opposed to your trust of all other areas of science

    No. They are certainly better than several other groups of scientists.

    Does it come from observations contradicting research..?

    Yes. e.g. didn’t IPCC AR4 predict zero Arctic summer ice woul not occur until near the end of the century?

    If denialists had something to say about climate, don’t you think it would be wisest for them to prove it scientifically?

    Could you call me a denier for thinking that mainstream climate science is underestimating climate change? I admit, “mainstream” is hard to define. I distrust the IPCC process because of its governmental influence.It is after all an “intergovernmental” panel. e.g. What happend to the Arctic climate feedbacks in IPCC SAR(1995)? They may not even be in IPCC AR5(2013).

    Comment by Geoff Beacon — 5 Sep 2011 @ 9:11 PM

  94. Really stunning present Arctic lack of ice, not only over the Arctic Ocean , everywhere I looked on my way back from the South I saw it. In particular Fox Basin devoid of sea ice, the capital of the world for Walrus devoid of ice pans. Literally all small glaciers are gone, or very little is left of them, so it is the beginning of a new Arctic look, thinner ice in winter giving no ice in summer. i think it lucky that the AO has switched of late. The last
    thing left, Arctic Ocean ice, survives by the grace of the winds and the reflection from summer clouds..

    Comment by wayne davidson — 5 Sep 2011 @ 9:23 PM

  95. My posting @91

    I sent the wrong version. I had rephrased the references to careers to be less strident. Climate scientists can have a hard time. I’m glad I’m not in their shoes.

    Comment by Geoff Beacon — 5 Sep 2011 @ 9:25 PM

  96. Hm, pardon a double post, but I posted this in the ‘unforced variations’ thread then realized there might be some relevance to Arctic sea ice:

    http://www.nature.com/climate/2009/0904/full/climate.2009.24.html
    “In 2007, scientists scouting the icy waters of the Arctic Ocean began to notice some troubling signs….”

    Coincidence, perhaps, that after a long stretch of no change, atmospheric methane started to rise in 2007. Same summer the ice was so reduced. Is there a correlation between the year’s sea ice and the year’s observations of methane bubbling out of the shallow seabed?

    Comment by Hank Roberts — 6 Sep 2011 @ 12:15 AM

  97. Geoff Beacon – Yes. e.g. didn’t IPCC AR4 predict zero Arctic summer ice woul not occur until near the end of the century?

    The relevant statement in the SPM is ‘Sea ice is projected to shrink in both the Arctic and Antarctic under all SRES scenarios. In some projections, arctic late-summer sea ice disappears almost entirely by the latter part of the 21st century. {10.3}’

    As you say there is a tentative forecast concerning the ‘latter part of the 21st century’. However, following the reference to 10.3.2.4 it becomes apparent what they’re talking about is not extent at the minumum but that over the July-September period.

    The July-September AR4 projections may be behind the curve but that’s not immediately obvious. Maybe someone could do a quick analysis.

    Comment by Paul S — 6 Sep 2011 @ 4:44 AM

  98. Hank,(96), I think you are on to something. Not only do longer periods of open water allow for more warming of the surface waters, more open water also allows for bigger waves and that turbulence helps mix the surface warmth the few meters to the shallow sea floor of the East Siberian Arctic Shelf and adjacent areas.

    Comment by wili — 6 Sep 2011 @ 8:44 AM

  99. Geoff @93
    Re: Clippo 86, You’re cherry-picking

    Yes I am, and to continue to do so I mention Willie Soon is also an Astrophysicist – do you trust him?

    I suggest you made a silly generalisation about ‘trust’ earlier – you need to examine your own personal criteria for judging who are real ‘authorities’ on subjects.

    And this is where I get the brownie points – I consider the independently peer-reviewed publishing Climate scientists, such as many who post here and run this site, to be real ‘authorities’ on various aspects of Climate Change.

    Comment by Clippo (UK) — 6 Sep 2011 @ 2:00 PM

  100. Here is a disturbing article about how spilled oil would behave in Arctic ice conditions:

    http://www.independent.co.uk/environment/oil-exploration-under-arctic-ice-could-cause-uncontrollable-natural-disaster-2349788.html

    Comment by Holly Stick — 6 Sep 2011 @ 3:49 PM

  101. I asked
    > Is there a correlation between the year’s sea ice and the
    > year’s observations of methane bubbling out of the shallow seabed?

    D’oh. When there’s ice covering the area, is anyone in a position for observing bubbles of methane coming up? or taking sea water samples for dissolved methane? So “observation of an increase” may be “increasing observation” rather than an actual change in what’s bubbling up.

    Further aside — we need to distinguish thawing of old methane clathrate from creation of new methane by organisms in the mud layer. And I recall some methane is coming up from deeper in the sediments where it’s warmer and then freezing out near the surface of the sediments because they’re colder due to sea water. Carbon isotopes should tell old from recent carbon.

    Comment by Hank Roberts — 6 Sep 2011 @ 4:46 PM

  102. Another aside — noting how the sea ice volume appears to be a new low record already.

    For an interesting misrepresentation of how much sea ice is hidden from the satellites, sunk deep below the water line, you can’t do better than the cover picture of Spencer’s book:
    http://ecx.images-amazon.com/images/I/41F8E2FNq1L._BO2,204,203,200_PIsitb-sticker-arrow-click,TopRight,35,-76_AA300_SH20_OU01_.jpg

    Anyone want to figure how much of that iceberg would actually show to a satellite? Hint — it wouldn’t be in that narrow vertical orientation.

    Comment by Hank Roberts — 6 Sep 2011 @ 4:56 PM

  103. It seems to me that with all your scientific discussion about the sea ice extent or area is not all that important. whether or not it is frozen, surely, is of little consequence. If it all melts, it makes little difference to the sea-level, so, why the problem.

    I am not a trained scientist, but I like to thing that I am a reasonably intelligent person and I find your discussion quite interesting, but, as a layman, I would like to know what is the situation of the areas of Land-Ice floes. I believe that these areas have amb ient air temperatures of -30 deg and -40 deg. Is that correct? If it is , then there can be no problem with regard to the land-ice melting. Would you agree?

    Comment by G.S. Williams — 6 Sep 2011 @ 5:38 PM

  104. What gets me puzzled is how Arctic SIE just came in as the second lowest for the month in the 1979 to 2011 satellite record, yet the Northwest Passage and the Northern Sea route weren’t open in 2007 IIRC (correct me if I’m wrong). I know currents and winds move it all about, but it just doesn’t add up. Or is area what I should be looking at?

    Comment by J Bowers — 6 Sep 2011 @ 7:42 PM

  105. 103

    a) Albedo. Look it up.

    b) No. Look it up.

    Are you Dickie Bird in disguise? Start Here button, top left of Home Page.

    Comment by Joe Cushley — 6 Sep 2011 @ 8:23 PM

  106. > G.S. Williams
    > I believe … is that correct?

    No.

    Can’t get a post with links past the spam filter right now, but if you put your own question into a Google search box, you’ll find plenty of information contradicting what you believe. You might ask whoever you got those ideas from where they found them.

    Try asking again in the open thread, and people can help you find more.

    Comment by Hank Roberts — 6 Sep 2011 @ 8:28 PM

  107. # 102 – Hank,

    I suspect you’ve been bitten by a berg bug. The book cover illustration overstates draft for a berg (at least one without an immensely high content of very dense minerals) by an order of magnitude or so, and bergs are a tiny fraction of the sea ice, by any measure, that are floating around.

    For the first time I noticed some pressure ridging of the Arctic Ocean’s ice pans from the bridge of the USCGC Healy at 88 North at on the 6th giving some variation to the ice’s cross section.

    http://mgds.ldeo.columbia.edu/healy/reports/aloftcon/2011/20110906-0401.jpeg

    Perhaps more representative, with the Canadian Louis S. St-Laurent in the distance just below the horizon mid frame, is the one at:

    http://mgds.ldeo.columbia.edu/healy/reports/aloftcon/2011/20110907-0001.jpeg

    The Lemont-Doherty Earth Observatory has links to the hourly images where the form of the ice is plain to see.

    http://mgds.ldeo.columbia.edu/healy/reports/aloftcon/2011/

    Comment by WhiteBeard — 6 Sep 2011 @ 9:12 PM

  108. #103–Well, a lot of things change when the sea ice goes.

    1) Most obviously, it’s a serious problem for the animals that use it as habitat: polar bears, walrus, ringed seals. Decapitating the food chain has been observed to cause cascading, unpredictable effects all the way down that chain, so we don’t know quite what will happen should those species suffer population crashes. However, the Inuit won’t like it much, as they still take seals for food.

    2) Increased coastal erosion is a predictable (and, actually, already observed) consequense: the land itself will be changed.

    3) Loss of sea ice will lead to increased regional warming due to two feedback mechanisms: increased water vapor (its a greenhouse gas par excellance, remember!) and the albedo feedback whereby the water of the Arctic Ocean absorbs greatly increased amounts of solar radiation during the summer.

    4) Land ice will be destabilized in some cases, so we can expect increased glacial calving and the like.

    J. Bowers, here’s a graph of the sea ice extent in the Canadian Archipelago. Note there’s basically no ice there this year, while in 2007 there was still rather a lot. The general answer to your question is that the ice distribution is different. Indeed, it’s never quite the same in any two years.

    For more on this, go to Neven’s Arctic Sea Ice blog (an easy Google away) and click on the “Daily Graphs” tab in the header. (The posted graph is one of the “Regional Graphs” found under a sub-menu there.)

    ftp://sidads.colorado.edu/DATASETS/NOAA/G02186/plots/r12_Bering_Sea_ts.png

    Comment by Kevin McKinney — 6 Sep 2011 @ 10:04 PM

  109. For Whitebeard:

    Spencer’s cover picture looks like these, but rotated 90 degrees and sunk far beyond its floating depth:

    Pressure ridge in multiyear sea ice
    http://www.britannica.com/EBchecked/media/93142/Pressure-ridge-in-multiyear-sea-ice-thrust-up-against-the

    http://www.neaq.org/conservation_and_research/climate_change/images/sea_ice_USGS.jpg “Multi-year Arctic sea ice”
    from http://www.neaq.org/conservation_and_research/climate_change/climate_change_basics.php
    http://www.nasa.gov/images/content/324805main_meierfig3_226x227.jpg

    Those aren’t as easy to find as they used to be:

    Coastal Engineering
    Volume 5, 1981-1982, Pages 159-169
    doi:10.1016/0378-3839(81)90013-2
    Received 4 February 1980; 14 January 1981.

    “This paper reviews an extensive body of published and unpublished literature to establish an estimate of the thickness in the ice cover of the Arctic Ocean…. It is concluded here that the maximum depth of ice likely to be encountered, (99% probability) is in the order of 50 to 55 ft (15 to 17 m).”

    Comment by Hank Roberts — 7 Sep 2011 @ 1:41 AM

  110. Well even if 2011 sets or almost sets a new record low for Arctic sea ice extent (and/or area).

    I can see the cherry pick from the Denialinati now …

    Presenter as years of record: 2007-2011 … also known as taking a Goddard Dump.

    Look see, no significant trend these last FIVE years, why has the Arctic STOPPED melting?

    Comment by EFS_Junior — 7 Sep 2011 @ 2:25 AM

  111. #110–Hey, it’s almost as if you’ve seen that before somewhere!!??

    /sarcasm

    Comment by Kevin McKinney — 7 Sep 2011 @ 7:26 AM

  112. New volume record low for August.

    http://neven1.typepad.com/blog/2011/09/piomas-august-2011.html

    Comment by wili — 7 Sep 2011 @ 7:36 AM

  113. Thanks Kevin (108)

    Comment by J Bowers — 7 Sep 2011 @ 7:43 AM

  114. Kevin, came across a good phrase on Neven’s blog for one other, somewhat hypothetical phenomenon a melted arctic may lead to- PETM 2.0. Ice gone over methane clatrates and change in warm water circulation is pretty scary over 1 trillion tons of methane carbon

    Comment by Thanes — 7 Sep 2011 @ 1:00 PM

  115. Well at least the artistic community finds the loss of ice troubling.

    http://www.google.com/hostednews/afp/article/ALeqM5g2pgSBr19vAe-nQpy8I5C2VUA0pg?docId=CNG.f1f5b8b061501ede51979a1e1f42063a.711

    Comment by spyder — 7 Sep 2011 @ 3:25 PM

  116. @108 Kevin McKinney

    Impacts on ocean circulation, atmospheric weather phenomenon today suggest more high impact storms. The collapse of the food chain works with many stressors, one begins with clorophyll …

    Alarming 40% decline in phytoplankton – base of marine ecosystem
    By John – Posted on 31 July 2010

    The July 28 issue of NATURE has a disturbing new study with strong evidence that phytoplankton have declined 40 percent in the last 50 years. That is based on a study of 450,000 ocean samples taken over the last century. Phytoplankton are critical because they:

    are the base of the entire ocean food chain, analogous to grasses and grains supporting land animals
    produce half of our life-supporting oxygen
    sequester 100 million tons of carbon dioxide daily, offsetting a substantial amount of the greenhouse gas produced from the burning of fossil fuels.
    Dr. Boris Worm, a noted marine biologist at Dalhousie University in Halifax, Nova Scotia, headed the study team. They spent three years unearthing, filtering and analyzing available data on ocean transparency and chlorophyll concentration — common ‘proxies’ for phytoplankton abundance. After removing data on shallow coastal waters and any obviously erroneous — that is, biologically impossible — observations, the data set still included some 450,000 globally distributed measurements collected between 1899 and 2008.

    The findings add to concerns that climate change is dangerously altering marine ecosystems. “This is severely disquieting,” adds Victor Smetacek, a marine biologist at the Alfred Wegener Institute of Polar and Marine Research in Bremerhaven, Germany. “One must really digest the very magnitude of this decline and its possible implications.”

    Added Paul Falkowski, an oceanographer at Rutgers University in New Brunswick, New Jersey. “Clearly, 40% is a huge number. This implies that the entire ocean system is out of steady state, slowing down.”

    Since 1899, ocean transparency has been measured using a simple device called a ‘Secchi disk’ after the Italian astronomer who invented it in 1865. The disk is lowered into the sea and a depth measurement is taken at the point where observers lose sight of it. Using optical equations, the researchers compared Secchi depth measurements of ocean transparency to measurements of chlorophyll concentrations at research sites and within phytoplankton, and to satellite observations of ocean color.

    The combined data suggest that phytoplankton biomass has decreased in eight of the ten ocean regions measured, with the largest rates of decline in the South and Equatorial Atlantic, the Arctic and the Southern Ocean. Only in the Indian Ocean has phytoplankton biomass increased — slightly in the north and more markedly in the south — since 1899.

    “The study adds to a growing body of global ocean research, all evidencing a fundamentally common result: the net effect of a warming ocean surface is a reduction in phytoplankton surface chlorophyll concentration,” says Michael Behrenfeld, a marine ecologist at Oregon State University in Corvallis. http://www.johnenglander.net/node/25

    Comment by prokaryotes — 7 Sep 2011 @ 6:58 PM

  117. > decline in plankton
    That’s more than a year old; it’s a serious issue (you want catastrophe? ask a starving whale). But look for more recent work. There’s more to this than that one article including some discussion: http://scholar.google.com/scholar?hl=en&q=plankton+decline and look at the 2011 work reported.

    There’s a classic feedback possible there: http://onlinelibrary.wiley.com/doi/10.1111/j.1467-2979.2010.00356.x/full
    and related articles for other species. See also Jeremy Jackson generally.

    Comment by Hank Roberts — 7 Sep 2011 @ 10:16 PM

  118. > plankton
    This is well worth reading:
    http://www.nature.com/nclimate/journal/v1/n1/full/nclimate1069.html?WT.ec_id=NCLIMATE-201104

    Hold onto your head while you read this:

    “when integrated over its entire area, the annual net photosynthetic production of the ocean is similar to that on land (around 50 Pg C yr−1)2. However, the biomass of phytoplankton responsible for this production is far smaller than its terrestrial plant counterpart. This difference implies a much faster turnover of the phytoplankton. Indeed, the entire global population of phytoplankton is replaced on average every two to six days….”

    There’s a fast feedback response to any environmental change!

    Comment by Hank Roberts — 8 Sep 2011 @ 12:41 AM

  119. Here’s yet another plot of the PIOMAS series:
    http://members.optusnet.com.au/anon10/PIOMAS.png
    And, fitting a curve (parabola) to the anomalies as others have done, you can project a summer zero towards the end of this decade:
    http://members.optusnet.com.au/anon10/PIOMAS1.png
    But the really interesting thing is that if you fit a curve to the raw volume data instead of the anomalies, you get an ice free arctic for half the year by the end of the next decade:
    http://members.optusnet.com.au/anon10/PIOMAS2.png

    That is less than 20 years away…

    Comment by GlenF — 8 Sep 2011 @ 2:14 AM

  120. #116–Troubling indeed, prokaryotes, and eminently worthy of comment.

    But what does it have to do with my response to the question of why the loss of sea ice matters?

    (Admittedly, there is a lot more that could be said on that topic than I said in my off-the-cuff response.)

    Comment by Kevin McKinney — 8 Sep 2011 @ 7:02 AM

  121. @120–why loss of sea ice matters

    I hope you have been reading the threads here.

    Loss of sea ice, beside the immediate effects on the animals in the region, is likely to dramatically change the weather patterns in much of the northern hemisphere. We are going from a polar region that was mostly ice and snow all year toward one that is open water half the year, and during that half, it is receiving constant sunlight. So there will be lots more water evaporated, which will both fall on surrounding land as rain and snow, and stay in the air as heat trapping water vapor. The further possible/probable consequences for this dramatic change are still being studied, afaik.

    An ice-free Arctic will also certainly change patterns of sea currents, but I am not up on studies that predict what might happen there. Changing patterns of sea currents will also greatly affect weather patterns.

    The effect of greatest concern to me is how ice-free waters expose seabed methane deposits in shallow parts of the continental shelves to warm water as the surface is warmed by the midnight sun and that surface warmth is agitated down to the few-meters-deep floor by the waves that can now freely propagate and grow across the unchained ocean.

    Ultimately, though, we can’t know all the consequences of turning an icy white top of the planet into a dark wet one, but they are likely to be profound.

    Comment by wili — 8 Sep 2011 @ 9:26 AM

  122. > why the loss of sea ice matters

    Putting that into Google finds plenty, have you looked? Then try Scholar.

    Comment by Hank Roberts — 8 Sep 2011 @ 9:57 AM

  123. So I have a question and would appreciate if I wasn’t decried as a heretic as part of the answer. Since the arctic ice cap floats, it is subjected to currents which bring ocean heat content north. That being the case, I would think that the ocean ice extent in the southern ocean would be far better corrolated with changes in air temperature than the arctic, where (just based on the comparative heat content of water v. air) I have to believe that the heat transported north by the currents must have a significant impact on ice volume… So if the southern ocean ice volume isn’t changing, it makes me wonder whether the increase in ocean heat content over the past twenty years is a larger factor than than increase in air temperatures in the arctic (which could concievably be at least partially a by-product of less ice). Is there some inherent problem with my logic?

    Comment by rich f — 8 Sep 2011 @ 1:50 PM

  124. rich f
    Why do you think the southern ocean ice volume is not changing?
    Where have you found increasing air temperatures cited as the cause of ice loss?

    The inherent problem I see with your logic is, something as complex as oceanic ice behavior is not a logic problem.

    Your question, clear of “logical connections”, seems to be: For Arctic ice loss, is the increase in ocean heat content over the past twenty years a larger factor than increase in air temperatures?

    In my non-scientist view, the answer would be Yes, a larger factor, not the only one, and north being a seperate collection of complexities than south.

    Comment by flxible — 8 Sep 2011 @ 2:35 PM

  125. Rich f. Ocean currents are probably playing a role, but there are others. Note that the Arctic is an ocean surrounded by land, while the Antarctic is a continent surrounded by ocean. They are polar opposites in more ways than the literal one. So one would not expect them to behave the same way. Also, the majority of land is in the Northern Hemisphere, so that is also where the largest sources of GHG’s and black carbon come from. Once these factors take hold, albedo change can play a strong reinforcing or ‘feedback’ role. And then there are feedbacks like methane starting to bubble out of tundra lakes and the shallows of continental shelves.

    It is rarely a good idea to look at just one system, such as ocean currents.

    (Others can perhaps give more technical–and perhaps accurate?–explanations.)

    Comment by wili — 8 Sep 2011 @ 2:48 PM

  126. When was the last time that the arctic was ice free? And when was the last time when the north pole was basically ice free (with remaining melt spots in the surrounding areas)?

    Comment by prokaryotes — 8 Sep 2011 @ 2:51 PM

  127. @120 Kevin McKinney (Admittedly, there is a lot more that could be said on that topic than I said in my off-the-cuff response.)

    Sorry, if that wasn’t clear but it was meant as supplemental data.

    Comment by prokaryotes — 8 Sep 2011 @ 2:53 PM

  128. Currents merit lots of attention. Outgoing currents must be matched by incoming currents, which might help explain conditions found under the receding lip of the Pine Island Glacier (my PIG link’s not handy).

    Comment by Pete Dunkelberg — 8 Sep 2011 @ 3:07 PM

  129. prokaryotes – re ice free arctic: arctic ice history

    Comment by flxible — 8 Sep 2011 @ 4:43 PM

  130. For Rich F: Often if you simply put your question into a search box you’ll find you can check what you assume is true against what’s been published. Looking at the science journals _will_ give you _different_answers_ than you get from the average opinion blog.

    Example:

    http://scholar.google.com/scholar?q=antarctic+ice+shelf+melting

    Second result is this one:

    “Rapid bottom melting widespread near Antarctic ice sheet grounding lines
    E. Rignot… – Science, 2002 – sciencemag.org
    The undersides of ice streams flowing from the Antarctic continent typically melt into the ocean where they cross the grounding line and begin to float as ice shelves and ice tongues (1). Unlike melting under the grounded ice sheet, processes beneath floating glaciers are governed …
    Cited by 186 ” <– often a clue it's worth reading; click the link on the search results page to see those papers, which have subsequently referred to this one. Follow the work through from 2002 to the present day that way.

    Someone said they'd checked and you're real, that should help people give you calm answers. The site here gets a lot of "homework help" requests, and a lot of people who heard something from some guy at a bar and want to repeat it prominently — so distinguishing yourself from them will get you somewhere.

    Note one thing people really will respect — if you use the "Open Thread" for your general questions, instead of putting them in a topic with a specific focus. Look in the right sidebar and at the top of the page for links.

    Lots of us here are just generally interested readers, many are (like me) not scientists, just trying to understand what's being written; the real scientists who are formal Contributors are named in the sidebar and the 'About' info again at top of page.

    Comment by Hank Roberts — 8 Sep 2011 @ 5:18 PM

  131. It is done: 2007 is promoted to ‘just another year of decline’.

    http://neven1.typepad.com/blog/2011/09/new-area-record.html

    Comment by cRR Kampen — 9 Sep 2011 @ 4:05 AM

  132. @ #108, Kevin, and #125, Wili,

    Kevin listed some repercussions of sea ice disappearance:

    [quote]

    1) Most obviously, it’s a serious problem for the animals that use it as habitat: polar bears, walrus, ringed seals. Decapitating the food chain has been observed to cause cascading, unpredictable effects all the way down that chain, so we don’t know quite what will happen should those species suffer population crashes. However, the Inuit won’t like it much, as they still take seals for food.

    2) Increased coastal erosion is a predictable (and, actually, already observed) consequense: the land itself will be changed.

    3) Loss of sea ice will lead to increased regional warming due to two feedback mechanisms: increased water vapor (its a greenhouse gas par excellance, remember!) and the albedo feedback whereby the water of the Arctic Ocean absorbs greatly increased amounts of solar radiation during the summer.

    4) Land ice will be destabilized in some cases, so we can expect increased glacial calving and the like.

    [end quote]

    To this I would add:

    5) Following from (3) there will be increased thawing of permafrost on land, leading to growing emissions of CO2 and methane – probably mostly methane. There is of the order of 1600 Gt of carbon locked up, double the amount already in the atmosphere [1]. It has been estimated that 30% permafrost will thaw by 2050 [2].

    6) Also following from (3) there will be warming of the shallow seas on the continental shelves, particularly the East Siberian Arctic Shelf (ESAS) where methane hydrate conditions have become critical, and, according to Shakhova et al [3], up to 50 Gt of methane could be released “at any time”, e.g. if there were an earthquake. A release of this size would multiply atmospheric methane by a factor of 11 (referred to as “methane x 11″ [4]), causing a climate forcing of the order of 10-20 W/m, almost certainly resulting in a methane feedback and runaway global warming. Forgive me for shouting but:

    THIS IS PERHAPS THE GREATEST DANGER FOR THE FUTURE OF HUMANITY, BECAUSE OF THE SPEED OF SEA ICE RETREAT AND WARMING OF THE ARCTIC OCEAN.

    7) Following from the warming (3) and the calving (4), the Greenland Ice Sheet (GIS) will produce 6 or 7 metres of sea level rise.

    8) Together with (7), there is mutual feedback between GIS and the West Antarctic Ice Sheet (WAIS), because the sea level rise lifts the base of the ice sheets where they meet the sea, causing ice sheet acceleration. According to Hansen, gravity measurements from satellite show that GIS ice sheet mass loss is doubling per decade [5].

    The albedo feedback, mentioned in (3), is extremely important, and will produce a net flux of the order of 1-2 petawatts of positive climate forcing when all the sea ice has gone. It’s producing about 40% of that now, which will rise to about 70% when the end-summer ice disappears (in 2015 according to PIOMAS exponential trend of sea ice volume) and near 100% when gone during 6 months of the summer (in 2020 or 2021 according to same model).

    This climate forcing produces an accelerated local warming, and is generally considered the cause of the “polar amplification” of global warming. From temperature data, the local temperature could be rising at 4-6 times the global average rate.

    The initiation of the Arctic warming is due to two main factors: local CO2 greenhouse gas effect and the warming of the Northern Atlantic currents flowing into the Arctic. The latter currents are fed from the Gulf Stream.

    The Arctic sea ice is generally accepted as crucial for the cooling of the planet, and implicated in the amplification of the Milankovitch cycles through cyclic variations in the warming of the mid-latitude Northern Hemisphere, which feed through the Gulf Stream into the Arctic and initiate positive feedback amplification, which is then cut off when there is a meltwater pulse to divert the Gulf Stream southwards and/or halt the Atlantic Meridional Overturning Circulation (AMOC), as happened at the start of the Younger Dryas.

    Basically, I believe we are at the point of breaking the amazing mechanism that has kept the temperature of the planet within certain limits over the whole of the ice ages – some 2.5 million years. We’ve broken it by injecting a colossal pulse of CO2 into the atmosphere – producing a greater concentration than in the past 15 million years or so. The sea ice is now amplifying the warming effect of this pulse, which is greater than the warming effect at the positive part of the Milankovitch cycle.

    Is the situation totally hopeless? Is the game over? No, not if we recognise the nature of the problem, and use geoengineering technology to cool the Arctic by one or two petawatts of negative forcing, however unsavoury one feels that to be – tampering with nature, playing God, cheap fix, etc.

    “Sometimes we have to do what’s required” – Sir Winston Churchill

    [1] http://www.ccrc.unsw.edu.au/Copenhagen/Copenhagen_Diagnosis_LOW.pdf

    [2] http://www.independent.co.uk/environment/russia-may-lose-30-of-permafrost-by-2050-official-2329447.html

    [3] http://en.wikipedia.org/wiki/Arctic_methane_release

    [4] http://www.atmos.washington.edu/academics/classes/2011Q2/558/IsaksenGB2011.pdf

    [5] http://www.columbia.edu/~jeh1/mailings/2011/20110118_MilankovicPaper.pdf

    Comment by John Nissen — 9 Sep 2011 @ 4:46 PM

  133. Univ of Bremen has recorded a record minimum aa of 8 sept 2011. They are confident NSIDC will follow suit.

    Comment by Petter H — 11 Sep 2011 @ 4:38 AM

  134. Hey All,

    Just wanted to interject a curiousity, given the current seasonality of insolation, what is the perdicted minimum polar ice coverage. It would seem that in the “Paleo” record there was a possibility of tropical conditions; however, it would also appear to be related to geo-specific positioning and ocean currents.

    So given current and near future techtonic pisitioning if the continents, ocean circulation, variations in the 250mb air currents and planetary tilt in relation to the current TSI imbalace has anyone predicted the probable polar ice minimum? Certainly it will not be absent with 6 months of less then 268K, at even 7 deg. F greater then the current minimum, there should easily be enough heat loss in the region to create a great seasonal mass of ice. If it remains in a land locked/bordered region such as the Canadian Maritime Is. would it not be likely to remain at similar levels for the next 100 years? Or would insolation and warm winds be sufficient to reduce the mass further. I would suspect that we may be seeing the min. with the given conditions.

    Even if the darkside radiative energy doubled and the GAT increased another 0.7 with a regional rise of another 7 deg. F, it would seem unlikely for insolation to increase. Warm winds seem to not significantly effect shaded snow in our region would it be more significant in the polar region?.

    My observations suggests it actually depends on the surface upon which ice sits for warming to significantly expedite it state change. Has anyone attempted an experiment to suggest a melt rate for ice on a porous surface in which the applied heat is in the form of surface winds to help us understand the efficiency of transfer of heat contained in the air towards the forcing of the state change of ice? (I suspect this value will prove to be relatively small.) At least with those efficiency of energy transfer values we can begin to ID root cause/prevention measures should we wish to change the inevitable.

    Cheers!
    Dave Cooke

    Comment by L. David Cooke — 12 Sep 2011 @ 11:08 AM

  135. > Has anyone attempted an experiment to suggest a melt rate for ice on a
    > porous surface in which the applied heat is in the form of surface winds

    Predict how long a ski resort could stay open in the spring, for example?

    Comment by Hank Roberts — 12 Sep 2011 @ 12:47 PM

  136. Hey Hank,

    In Switzerland, a plastic cover surrounding a grooming tractor sitting beside a tree in 2005 preserved the snow there all year. Based on plastic cover tests done near moulins in Greenland, the ice was 1/2 meter thicker and harder over a period of a week. Insolation or it’s preventation has been proven to increase ice durability by 6 months. Hence, dense cloud cover could add potential durability, if the oceans were also sufficiently shaded. A broad covering of Sargasso seaweed and a +VE or +NAO goes a long way to preserving sea ice.

    To me that is a major issue, what is changing the synoptics so drastically, that Blocking Highs and Cutoff Lows have increased both in population and duration. To have the Azores/Bermuda High in retrograde to the point it Centers in Western Carolina or SW Georgia is way abnormal. A deg. C more warmth in the GoM or Caribbean Sea is not going to cause that, nor is 134ppm more CO2,

    A swollen N. Jet Stream which has deviated nearly 20 deg. from it’s former Summer average, now that is something to explore…

    Cheers!
    Dave Cooke

    Comment by L. David Cooke — 12 Sep 2011 @ 3:13 PM

  137. Minimum reached?

    Comment by John Brookes — 14 Sep 2011 @ 9:11 AM

  138. I’m going to go out on a limb and say yes for extent and area, possibly not for volume, but also likely yes. If the clouds disappear for the next ten days, we might see some more downward trends, but the AO is positive, so…

    Comment by ccpo — 14 Sep 2011 @ 9:37 AM

  139. Has anyone else seen this:

    http://arctictransport.wordpress.com/

    “Commercial shipping through the Northeast Passage over the last couple weeks has reported the seas bubbling as if they were boiling. Their observations have been reported to the science ministry who have sent scientists to investigate.”

    Does anyone know about this source? Is it usually reliable?

    Does anyone else find the notion of “seas bubbling as if they were boiling” a bit…disconcerting?

    Comment by wili — 14 Sep 2011 @ 8:04 PM

  140. 139 wili says:

    Does anyone else find the notion of “seas bubbling as if they were boiling” a bit…disconcerting?

    Yes, but expected. What was it, two years ago they reported a tripling in the number of thermokarst lakes?

    The problems are very complex, but the answer are exceedingly simple: Reforestation, regenerative agriculture, food forests, reduced consumption (based in smaller, semi-autonomous communities) and some sort of sustainable/steady-state economy (See Steve Keen for possible economic modeling of the steady-state), etc.

    Comment by ccpo — 17 Sep 2011 @ 1:18 PM

  141. I dont speak russian, but they have lots of research into the arctic methane release and permafrost… Im sure their research will be very usefull once translated to english..

    http://arcticportal.org/events/view/62/122

    Comment by harvey — 17 Sep 2011 @ 2:55 PM

  142. Why is there nothing on this site regarding Antarctic ice accretion?

    [Response: What Antarctic ice accretion? (land ice, sea ice) - gavin]

    Comment by WA Piper — 20 Sep 2011 @ 9:59 AM

  143. There is strong evidence of freezing in the center of the Arctic Ocean ice pack (colder than -11 C), but unlikely likewise at its edges, there was in the last few days displacement of multi-year ice in the Canadian archipelago Northern channels. Very much pushed by a significant cold low pressure system. Daily winds have favored less flushing quite a lot lately, but the melt was really big , would have been seen much more as such if the winds were more in line with the sea current., Dominance of surface adiabatic lapse rates, with scant presence of inversions may persist over the wider open very warm arctic ocean. This gives rather thick lower clouds dominating the entire Arctic, but is rather a sign that the sea is feeding back some heat it acquired over the summer. I suspect that the coming re-freeze would be not as fast as 2007 because of an overall lesser melt of multi-year much less salty ice and by also the warmer seas fueling a quasi total cloudy state.

    Comment by wayne davidson — 20 Sep 2011 @ 11:03 PM

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