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  1. Has anyone seen the uni-bremen arctic sea ice extent graph? Looks to me as though we are well on track to post another record september summer low. While the 2011 line was scraping the bottom as the lowest maximum on record it is now falling more rapidly than i have ever seen as you would expect with a rapidly warming arctic ocean under the fragile sea ice…if something miraculous doesn’t happen from now to september it looks very much as though we will smash the benchmark 2007 summer low.
    At this point i might remind you all that this is not happening in geological time..rather this disaster is happening on virtually a year by year basis. Very soon..we will have no more permament summer sea ice left and the winter ice sheet will have shrunk to a cataclysmic low. We shall see firsthand the vital importance the arctic icecap has on world climate..for all those remaining sceptics out there with their heads firmly wedged in the sand bucket of ignorance. Those graphs show to me that we have gone way beyond the tipping points regarning ice albedo..from now on and for at least the last 40 odd years we have created an environment juggernaut of unstoppable climate change that is not going to be reversable for many many centuries to come.

    Comment by lawrence coleman — 20 Jul 2011 @ 6:47 AM

  2. A question for everyone:

    Does/will Arctic summer ses ice melt then impact Greenland further, ie; if the summer sea ice melt accelerates (now on track possibly for a 2030-2040 Arctic summer sea being ice free. I know we have wide projections/predictions for sea level rise but 0.5-2 meters is quoted for end of the century total sea level rise but is 5 meters possible in 90 years as Hansen once tentatively suggested.

    50 cm a decade is 5 a year or 50 mm. Is it possible BAU ?

    Comment by pete best — 20 Jul 2011 @ 7:44 AM

  3. Every ice reserve on the planet is decreasing. It is my simplistic contention that it is the melting of the ice reserves that is preventing runaway global warming. Sooner or later the energy sink which ice provides as it melts and sublimes will be inadequate to counter the solar input and both temperature and sea level will rapidly rise simultaneously. The only question is when this will occur.

    jadavison.wordpress.com

    Comment by John A. Davison — 20 Jul 2011 @ 9:12 AM

  4. Current temps are up 6-8 degrees C above normal and we are already at all time lows. Only a sudden change in conditions up there will keep us from hitting a new record. This is also being discussed over at Climate Progress, and in a rare mid-month post over at NSIDC.

    http://nsidc.org/arcticseaicenews/index.html

    Comment by wili — 20 Jul 2011 @ 9:14 AM

  5. #2 pete best

    Whilst the seasonal disappearance of Arctic sea ice would make some difference, I wouldn’t expect such a difference to be large. It’s worth reminding yourself, by looking at the NSIDC charts, that it has been usual for the sea ice around half of Greenland to disappear each year, even before the recent dramatic decline in summer Arctic sea ice extents.

    What might start to happen later in the century is that the sea-ice would retreat earlier in the season, allowing more sunlight to be absorbed by the oceans, and so more heat would be lost by the oceans in the Arctic autumn. One presumes that this could extend the melting season for Greenland, but it would also represent a relatively large source of water vapour, so perhaps more snow on the summit too.

    I know there are a lot of modelling efforts being made to look at Greenland, so hopefully there will be a lot more on this sort of thing in AR5.

    Comment by Timothy — 20 Jul 2011 @ 9:19 AM

  6. Sorry to be so ignorant, but how much will it matter if the sea ice extent in 2011 turns out to be less than the 2007 low?

    Comment by Hunt Janin — 20 Jul 2011 @ 9:20 AM

  7. It’s important, while pondering a single year, to keep in mind long-term trends. There was a “regime change” in Arctic Ocean ice more than a decade ago that is still exerting an influence, as Ignatius Rigor and others have reported. More here:
    Thin Ice the Norm in Warming Arctic – http://nyti.ms/osf21G
    and here:
    http://dotearth.blogs.nytimes.com/2010/09/14/arctic-sea-ice-continues-its-summer-slide/

    Comment by Andy Revkin — 20 Jul 2011 @ 9:21 AM

  8. Some readers may also want to take a look at NSIDC’s Arctic Sea Ice News and Analysis” site (http://nsidc.org/arcticseaicenews/). We just posted a new piece discussing conditions through mid July. As we get towards the seasonal minimum in September, we be putting out discussion pieces on a two-week and then a weekly basis. Regarding the rapid decline in ice extent over the past few weeks, it appears that a key driver has been a strong anticyclone centered over the northern Beaufort Sea which tends to promote warm conditions and convergent ice motion. There are signs that that pattern is now starting to break down but we’ll have to wait and see. Furthermore, melt onset was quite early over much of the Arctic Ocean.

    Comment by Mark Serreze — 20 Jul 2011 @ 9:26 AM

  9. Northeast passage is about to be open at any moment soon , a stunning world record, and I present on my blog, http://eh2r.blogspot.com/, wide open water North of Greenland, equally shocking.

    Comment by wayne davidson — 20 Jul 2011 @ 9:30 AM

  10. James Hansen suggests that the portion of sea-level rise contributed by melting ice is non-linear and is best predicted by inspecting its doubling time. That he measures at 5 to 10 years. That in turn gives us a total rise of around 5m by the end of the century. But most of that comes in the last decade or two.

    Comment by ian perrin — 20 Jul 2011 @ 9:33 AM

  11. James Hansen spoke from the 5 meters sea level rise only under two assumptions: We dont cut back our GHG emissions and do business as usual. This would lead to more than 600 ppm of CO2 till the end of the century. The second assumption is, that ice sheets are becoming instable and disintegrate, e.g. float faster into the oceans. If both assumptions would be true, it could be realistic that we would see such a drastic sea level rise. But if the ice sheets will become so instable is not clear at the moment, it is only a possibility. And it is also not clear, if we do business as usual. If we cut back our emissions, the sea level rise would logically be much smaller. So, the 5m is a possible worst-case scenario.

    Comment by observer — 20 Jul 2011 @ 9:43 AM

  12. Why is the overall knowledge, attention and interest about this region that low. Strangely enough same companies denying consequences of CO2 emissions prepare to get hands on the resources below a diminished ice pack.

    The Arctic presents climate change in fast forward mode every day: http://www.arctic.io/satellite

    Are we waiting for the moment the last million square miles 5cm thick disappear within one day? Who is blocking inevitable funding of Arctic research?

    What can we expect as weather on the northern hemisphere when the Arctic is ice free soon?

    Comment by arcticio — 20 Jul 2011 @ 9:45 AM

  13. @pete best

    2m of sea level rise by 2100 is usually considered the maximum plausible under any circumstances.

    See these links below, or indeed just search Realclimate for “sea level rise” and you’ll get the same answer.
    http://www.nature.com/climate/2010/1004/full/climate.2010.30.html
    http://www.youtube.com/watch?v=ybjg0ZN3jl0
    http://www.timesonline.co.uk/tol/news/environment/article6982299.ece
    http://www.endsreport.com/19501/sea-level-forecast-is-good-news-for-flood-planners

    Comment by simon evans — 20 Jul 2011 @ 9:50 AM

  14. I saw a graph recently, from Hansen I believe, of an exponential curve going to 5 meters of sea level rise by 2100. It had a slow take-off. The 50mm/year mark wouldn’t be crossed for several decades. But then, that last decade of this century would see @#$#^% INSANE rise. And assuming time doesn’t stop when the graph does, the beginning of the 2100s would see a coastline changing so fast you could practically sit at the shore and watch it advance. (that’s hyperbole, but it would be really really fast)

    Comment by Kevin Stanley — 20 Jul 2011 @ 9:56 AM

  15. @ Pete Best: If the rise is exponential through the rest of the century, with a slow take-off (as I believe Hansen envisioned), I believe it would be possible, but we wouldn’t see anything like 50mm/year for several decades. Near the end of the century, though, you’d practically be able to stand at the shore and watch it advance….

    Comment by Kevin Stanley — 20 Jul 2011 @ 10:00 AM

  16. Is it just me or is there a bit of creep in the date of the lowest sea ice extent? Or is a better interpretation that the lower the minimum, the later the date of the minimum ice is?

    Comment by Chris — 20 Jul 2011 @ 10:31 AM

  17. What’s the expert opinion on the graph that fits quadratic trendlines to the monthly PIOMAS data, which Neven posted back in April:
    http://neven1.typepad.com/blog/2011/05/piomas-april-2011.html
    It certainly seems a more plausible fit than the linear trends they always show on the official PIOMAS charts. But did anyone test the fit properly, and if so, do the extrapolation of these lines over the next few years have any credibility?

    Comment by Steve Easterbrook — 20 Jul 2011 @ 10:34 AM

  18. I’m an amateur in this area – my only experience is closely watching the ice over the last 5 or 6 melt seasons. I am guardedly optimistic about this year, because of the condition of the sea-ice in the central arctic, as shown on MODIS. I expect the melt rate to reduce markedly in the next few weeks, and the September minimum extent to be somewhere around that of 2008.

    Comment by Nick Barnes — 20 Jul 2011 @ 10:41 AM

  19. Like most people here, I’m watching the ice situation at both poles plus Greenland with more than passing interest. Aside from the obvious warming/feedback implication, I’m interested in what the public reaction will be to hitting zero ice, even briefly, during the summer. I would like to think that it would be such a dramatic event, one that would garner so much media attention, that it would have a profound effect on the public, much as the famous photo of Earth from one of the pre-landing Apollo missions supposedly did. (And yes, today is the anniversary of Neil and Buzz strolling on the moon, while Michael took an extended joy ride.)

    Which brings me to the issue of when we might see that ice-free period. Over on Neven’s Arctic Sea Ice Blog, he posted a graph in May (http://neven1.typepad.com/blog/2011/05/piomas-april-2011.html) in which someone did a quadratic projection of the trends for each month. Just eyeballing it, the quad. approach seems to fit the existing data very well. The problem is that it yields a projection of August, September, and October being ice free in 2018. I would love to hear someone explain what’s wrong with this picture, as even those three months being essentially ice free by 2030 or 2040 is alarming. (If nothing else, I would expect to see the trend lines flatten out as the thicker ice, while still declining, will constitute a higher percentage of the total ice. That should slow down the progression somewhat, shouldn’t it?)

    Everyone here: Please feel free to use my newly reworked graphs page (http://www.grinzo.com/energy/graphs.html) which includes links to numerous energy, climate, and weather graphics. Suggestions for improvements are welcome, of course.

    Comment by Lou Grinzo — 20 Jul 2011 @ 10:54 AM

  20. I am surprised to note that almost all the comments are concentrated on the sea level rise more or less tied to the arctic ice extend. Can I just remind everybody that sea level is absolutely not concerned by this extend. The level of your glass does not change when the ice cube floating at the surface melts.

    [Response: Actually that isn't quite true for Arctic sea ice, the reason being that sea ice is relatively fresh (~5 psu) and it is floating on salty sea water (~34 psu). That means that the volume of water of the ice melt is slightly greater than the volume of sea water displaced, and so that when the ice melts, it does raise sea level slightly. This isn't an important factor in global sea level rise, but it's best to be accurate in these things. - gavin]

    Comment by Pierre Allemand — 20 Jul 2011 @ 10:55 AM

  21. Could sea ice possibly be a black swan situation?

    Comment by Hunt Janin — 20 Jul 2011 @ 11:00 AM

  22. @Chris:

    The main driver in the actual date of minimum ice extent is weather. The ice in September even in the old days was less compact than in winter. If you have wind blowing one way, it could push the ice together and lower the ice extent. If it blows another way, the ice spreads apart, increasing ice extent. The ice area (the area of water covered by ice, not including the open water) is the same, but the extent varies, at least in this thought experiment.

    It happens that the last two years, there has been an early freeze-up (1st or 2nd week of September) where the ice extent starts increasing. But this was followed by another short warm period where the ice started melting again and went below the first value in early September. This is why, for climate, it’s more important to look at the monthly average than the day-to-day values.

    The National Ice Center (NIC) in Washington DC is the government agency responsible for monitoring sea ice conditions, and they release a projection every June 1 predicting the opening and closing dates for the shipping channel between Barrow and Prudhoe Bay, Alaska, as well as tabulating past dates since the 1950s. If you look at the dates of opening, they are trending earlier. But the dates of closing are not getting later, and they can vary by 2-3 weeks from one year to the next. That suggests the opening is more determined by the state of the climate and the closing is more determined by the weather.

    Comment by todd arbetter — 20 Jul 2011 @ 11:34 AM

  23. Re 3 John A. Davison – It’s great to realize that there is a latent heat of melting, but quantifying it, it’s not so large an energy sink. A period of rapid melt would reduce or concievably could temporarily reverse global warming, but I don’t think that’s happenned yet.

    These might not be the correct proportions to consider but for what it’s worth:

    3 K warming * 3000 m (rounded up from memory of what ocean depth would be if spread out over global area) * 1000 kg/m3 * ~ 4.2 kJ/(kg*K) ~=
    38 GJ/m2

    10 m sea level rise from melting * 0.7 (fraction of globe that is ocean) *
    1000 kg/m3 * 334 kJ/kg (latent heat) ~=
    2.34 GJ/m2

    Of course it may take ~ 1000 years to get the deep oceans ‘up to speed’, but there is also an equilibration delay in the ice sheets. But graphs I’ve seen of warming thus far show most additional heat going into the ocean (aside from melting ice, there’s also air heat capacity, latent heat of increasing atmopsheric water vapor, and heating of the land surface and crust (the effective depth which is affected at relevant time scale, which isn’t much).

    Comment by Patrick 027 — 20 Jul 2011 @ 11:41 AM

  24. “could temporarily reverse global warming”
    in terms of temperature, not heat

    Comment by Patrick 027 — 20 Jul 2011 @ 11:43 AM

  25. What are the implications of an ice free Arctic in summer, for weather in the northern hemisphere and South Asia in particular?
    Could anyone suggest any reliable studies about this?
    Nagraj
    New Delhi

    Comment by Nagraj Adve — 20 Jul 2011 @ 12:11 PM

  26. Isn’t this close to the trend line over the last 30 years, and isn’t that trend line almost perfectly linear, lacking any quadratic or higher order polynomial? It’s threatening enough if it continues a linear decline.

    Comment by Septic Matthew — 20 Jul 2011 @ 12:15 PM

  27. While the minimum this year may end up being very low, it is worth noticing that in the IJIS data, the ranking of a year in July doesn’t seem to be a very good predictor of where it will bottom out in September. I would urge some caution before assuming that this will be a record/near record year. It would be nice to repeat this thread in September.

    Comment by mps — 20 Jul 2011 @ 12:27 PM

  28. Regarding the rapid decline in ice extent over the past few weeks, it appears that a key driver has been a strong anticyclone centered over the northern Beaufort Sea which tends to promote warm conditions and convergent ice motion. There are signs that that pattern is now starting to break down but we’ll have to wait and see.

    I concur with Dr. Serreze here. Things were pretty stable and conducive to extent decrease so far, but the weather has been changing the last few days and will continue to do so. It’s not clear yet what the effect on extent decrease will be, but I’m pretty sure there will be a slowdown at first (which we have been witnessing since yesterday actually).

    I write regular updates on what’s been happening and what might happen in the short term on the Arctic Sea Ice blog, and some other stuff like animations and comparisons between this year’s melt and that of previous years. Most of the interesting stuff is in the comment sections though.

    I’m pretty confident this year’s minimum will come in lower than last year’s, but it’s too early to tell if there will be a new record. And to look a bit further ahead, it will also be interesting to see after the minimum has occurred, if we get a third NH weird winter in a row.

    Comment by Neven — 20 Jul 2011 @ 12:42 PM

  29. Nick, #18

    “I am guardedly optimistic about this year,” No such “ice is getting better” thing is happening:”

    http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2.png?%3C?php%20echo%20time()%20?

    volume dropping seems in free fall. You have to incorporate volume in your mental calculations.

    Comment by wayne davidson — 20 Jul 2011 @ 12:50 PM

  30. How many millions of tonnes of shipping have passed through the navigable waters of the north east and north west passges without ice breakers?

    Comment by Stacey — 20 Jul 2011 @ 12:57 PM

  31. Pierre:

    I am surprised to note that almost all the comments are concentrated on the sea level rise more or less tied to the arctic ice extend.

    No, they aren’t.

    Someone asked “Does/will Arctic summer ses ice melt then impact Greenland further”, i.e. the Greenland Ice Sheet, which is on land.

    Then people started talking about possible increases in the rate of sea level rise, *in the context* of the question raised about the Greenland Ice Sheet.

    I suppose everyone could make absolutely clear whether they’re talking about sea or land ice in each post, but the average poster here is knowledgable enough that the implicit context is clear.

    Comment by dhogaza — 20 Jul 2011 @ 1:20 PM

  32. At least as important as sea ice extent are (1) the dates of minimum and maximum extent within a particular basin and (2) the type of ice that makes up a given year’s sea ice. The steady decline in the amount of multi-year ice in most, if not all, basins may be of greater long-term importance than any given years’ variations of extent.

    Regarding P. Best’s #2, there is growing evidence that the stability of Greenland’s tidewater glaciers (basically those that end in fjords) is related to the water column temperatures at the glacier/ocean interface. Many, if not most, of Greenland’s glaciers’ grounding lines are well below sea level. If a warming ocean can eat away at a glacier’s terminus, it will retreat inland into the ice sheet followed by the ocean.

    It’s a thorny problem.

    Comment by BillS — 20 Jul 2011 @ 1:43 PM

  33. septic matthew:

    Isn’t this close to the trend line over the last 30 years, and isn’t that trend line almost perfectly linear, lacking any quadratic or higher order polynomial? It’s threatening enough if it continues a linear decline.

    Here’s a post by Tamino made shortly after the NSDIC data for September 2010 was made available, using a quadratic fit. It captures the annual variance within its 95% confidence intervals except for one year which barely lay outside that range.

    He extrapolated that to come up with a prediction for the 2011 minima (using JAXA) of 4.63 +/- 0.9 million km^2. Admittedly a wide range but it’s looking pretty good for a prediction made 11 months before the upcoming minima.

    Check out the post, it’s good …

    Comment by dhogaza — 20 Jul 2011 @ 1:46 PM

  34. Here’s a couple of thoughts on this years melt:

    It will obviously be a race to see if 2011 can beat 2007 for the lowest summer minimum on modern satellite record…a lot of course depends more on weather. Especially of interest will be to see if a sustained dipole anomaly will set up going into August and how much this impacts ice export through the Fram strait and bringing some warmer late summer meridional winds across the arctic.

    But more to the point in comparison between 2011 and 2007: Ice extent is probably not the best metric to compare these two years, for even if 2011 nudges 2007 out of “lowest extent on record” or comes in slightly higher, 2011 still easily blows away every other year for the lowest sea ice volume on record. Simply put, there’s just a whole lot less sea ice than any other year on modern record. The variability of the weather will determine the final extent for this year, but the long-term trend of sea ice is clearly continuing to spiral down, and despite the pronouncements of some skeptics about a “recovery”, the Arctic continues strongly on target to become ice free, or virtually so, in the next few decades.

    Comment by R. Gates — 20 Jul 2011 @ 1:56 PM

  35. So, is there any plausible case where the following is NOT going to happen during this century:

    1. Rapidly warming arctic melts the sea ice.

    2. Melting sea ice exposes more and more open ocean.

    3. Open ocean absorbs more solar energy, thereby accelerating the warming and the melting, and exposing more open ocean, which absorbs even more solar energy.

    4. Steps 1-3 continue until Arctic warms sufficiently to thaw permafrost/tundra and to destabilize underwater clathrates, thereby releasing vast amounts of methane.

    5. Game over; PETM extinction looks like a picnic by comparison.

    Comment by SecularAnimist — 20 Jul 2011 @ 1:58 PM

  36. Apologies for this question, which is way OT: today’s NY Times Room for Debate> features Roger Pielke Jr. discussing corruption in world soccer with two other people. Is he the same Roger Pielke Jr. who has attracted so much unfavorable notice at Eli Rabett’s and at other climate-related blogs?

    Apologies again, I used to read Eli faithfully but haven’t had much time to do that this year.

    Comment by JPS, FCD — 20 Jul 2011 @ 2:01 PM

  37. re: #27 mps “in the IJIS data, the ranking of a year in July doesn’t seem to be a very good predictor of where it will bottom out in September.”

    I played with the IJIS data a bit, and while this also probably isn’t a great predictor, I found it entertaining:
    I took the daily changes in extent for 7/20 through 9/30 for each year from 2003 to 2010, and grafted them onto the 2011 data up to 7/19. So basically I had the answer to the question “if the same amount of ice extent is lost from this date forward as was lost in 20XX (where XX is 03-10), what would the minimum be?”

    The range I got was from a high value of 5,017,813 km2 (equivalent losses for the rest of the season to the corresponding period in 2006) to a low of 3,650,782 km2 (corresponding to losses from this date forward in 2008). Data from half the years (’04,’07,’08,’10) led to a new record minimum, data from the other four didn’t (’03, ’05, ’06 , ’09). The average of all 8 was very close to the IJIS minimum extent: 4,264,785 km2.

    Scientific? Hell no. But I found it interesting as just a rough indication of what the minimum would look like if the melt season progressed from here as recent seasons have–which it probably won’t, of course…thinner ice, earlier melt onset, so much more solar energy from those clear skies and dark waters of the last few weeks…and who knows what the weather might do….

    Comment by Kevin Stanley — 20 Jul 2011 @ 2:12 PM

  38. #30 Stacey

    “How many millions of tonnes of shipping have passed through the navigable waters of the north east and north west passges without ice breakers?”

    In the lore of Arctic shipping, all good captains past and present day, fear ice, so much so that the NW passage was sketched as the equivalent as death for sailors. Hence proving that the passage was never open as now a days. It is a matter of a shipping company to dissuade their good captains that the ice is gone.

    Comment by wayne davidson — 20 Jul 2011 @ 2:29 PM

  39. Hansen and Sato argue in their latest draft paper (p.22 and on) that rapid melting of Arctic sea ice due to BAU emissions will probably cause acceleration and even disintegration of (vulnerable parts of) the Greenland and West-Antarctic ice sheets during this century:

    http://arxiv.org/ftp/arxiv/papers/1105/1105.0968.pdf

    Assuming a doubling time in melt rate of 10 years this could cause about 5 meters of sea level rise by 2100. In the last few decades of this century that would mean more than 1 and even 2 meters of sea level rise per decade.

    However, they also argue that the many and massive resulting icebergs would cause a negative feedback by cooling the ocean surface that would limit the maximum melt rate to maybe 1 meter per decade (that estimate is from their first draft; it’s not in the second). So that would maybe limit maximum sea level rise by 2100 to around 4 meters?

    After 2100 ice would keep melting and sea level rising for many centuries. If Hansen and Sato are correct in their estimate of 1 meter/decade as the maximum rate of SLR, then 14 meters of SLR in 2200 and 70 meters before the end of the millennium would be the current worst-case scenario as far as SLR is concerned.

    Comment by Lennart van der Linde — 20 Jul 2011 @ 2:36 PM

  40. 33, dhogaza

    thank you

    Comment by Septic Matthew — 20 Jul 2011 @ 2:54 PM

  41. Hansen said earlier this year, that temperatures as they are now, just slightly above the warmest part of the Holocene, Ice sheets become ‘unstable’. Considering we are now at the warmest part of the Holocene- and ice melt in the arctic seems to be accelerating – he is right. If we reach the lows of 2007, odds are that by 2020, we will see half of what we have this year or 2007.

    Comment by PeterM — 20 Jul 2011 @ 2:59 PM

  42. > 30 … how many ….?

    You can start counting with this one:
    http://www.alaskadispatch.com/article/first-commercial-ship-sails-through-northwest-passage
    Sep 07, 2010

    Comment by Hank Roberts — 20 Jul 2011 @ 3:05 PM

  43. Sorry for being OT, but a claim came up on a blog recently — does the U.S. federal government spend $4billion per year on global warming studies? And if so, what can we compare that with……like how much it spends on the space program or wars.

    Comment by Lynn Vincentnathan — 20 Jul 2011 @ 3:09 PM

  44. #36 It is indeed, a man of many parts.

    http://sciencepolicy.colorado.edu/about_us/meet_us/roger_pielke/

    Comment by BillS — 20 Jul 2011 @ 3:12 PM

  45. An alternative to linear or quadratic representations of the trend in Arctic sea ice is the asymmetrical S-shaped Gompertz curve, applied to ice extent here,
    http://neven1.typepad.com/blog/2011/04/trends-in-arctic-sea-ice-extent.html
    (2011 Sep mean prediction 4.4m km^2)
    and to ice area and volume here,
    http://neven1.typepad.com/blog/2011/04/trends-in-arctic-sea-ice-volume.html
    (volume looks like it’s crashing soon).
    Chris Randles and I have both contributed Gompertz-based guesses to the July SEARCH Sea Ice Outlook.
    http://www.arcus.org/search/seaiceoutlook/2011/july

    Although Gompertz curves are just as unphysical and naive as linear or quadratic models, they offer several appealing features:
    - fit the recent steepening decline better than linear
    - fit the gradual 1970s-1980s decline better than linear or quadratic
    - imply a rapid but ultimately asymptotic approach to zero ice.

    How well our 4.4 predictions compare with this year’s reality, or with more sophisticated models in the SEARCH SIO, we’ll see in a few months.

    Comment by L Hamilton — 20 Jul 2011 @ 3:15 PM

  46. Some context: Mid July and the ice area is typical of what could be expected for the September minimum in the 1980s.

    #35 Secular Animist,
    Add in the speed of warming of the ocean, and the speed of warming of the sea bottom sediments and we may find the clathrate issue is more ‘chronic’ than ‘catastrophic’.
    http://geosci.uchicago.edu/~archer/reprints/archer.2007.hydrate_rev.pdf
    Archer “Methane hydrate stability and anthropogenic climate change”, Biogeosciences, 2007.

    I’m not saying it’s not a problem, just disagreeing on the sort of problem it looks likely to be.

    Comment by Chris R — 20 Jul 2011 @ 3:16 PM

  47. Sort of preceding Steve Easterbrook’s question (#17) about quadratic fits to PIOMAS, I’d like to ask how much confidence it’s right to have in the PIOMAS data in the first place? As I understand it it’s essentially a model which is tweaked using the available observations. What I have no idea about is how good is that tweaking at keeping the results real.

    Comment by Ed Davies — 20 Jul 2011 @ 3:43 PM

  48. I’ve posted an update to my prediction for the 2011 minimum sea ice extent.

    Comment by tamino — 20 Jul 2011 @ 3:53 PM

  49. A simple soul, I cannot understand why anyone pays any attention to the sea ice extent. Counting ice-cubes/ square Km must be the least scientific measure, to the point of uselessness, of any climate warming measure. Sure, at one time it was all we had, but with the advent of satellite volume measure it’s time to relegate it to science’s trashcan.
    Danmarks Meteorologoische shows arctic warming returning to the 50 yr average since May while Washington U’s ice volume measure continues to plunge without hesitation. Perhaps the Arctic has reached the point where weather anomolies will have no effect upon the overall trends.

    [Response: The DMI temperature data is a model simulation that is being compared to another model simulation (ERA 40) and with no bias correction related to different models or input data series over time. As is, even trends within a single reanalysis are suspect, thinking that that the comparison of two re-analyses run over different time periods with different models is credible, is the height of foolishness. - gavin]

    Comment by w kensit — 20 Jul 2011 @ 4:25 PM

  50. wayne #29,

    No such “ice is getting better” thing is happening

    I didn’t say the ice is getting better. Certainly we are going to see very low ice this year, and worse in years to come. As for PIOMAS, I am discounting it entirely because the volume numbers suggest a much larger departure in the last couple of years, compared to the previous decade, than I think we are seeing. I’m eager to see live, detailed, calibrated, Cryosat data come online. I agree that if PIOMAS is accurate, we will certainly see a dramatic new record set this year. But if the ice had been as thin as PIOMAS suggested then the solsticial clear skies this year would have left the central arctic basin in tatters. Look at a recent MODIS shot of the central arctic, like this one from yesterday:

    http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r04c03.2011200.terra.1km

    100% concentration, no significant leads. Compare to this, the same area on the same date last year:

    http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r04c03.2010200.terra.1km

    My sense that this year’s melt is going to bottom out at maybe 4.7 or 4.8 (Mkm^2 IJIS extent) is based largely on looking at pictures like that.

    Comment by Nick Barnes — 20 Jul 2011 @ 4:41 PM

  51. Re shipping through the NWP or NEP (#30, #38 and #42):

    The short answer to Stacey’s question is “zero.” The total tonnage through both Passages together probably doesn’t reach 200,000, and it’s as close to that number as it is mostly due to a 100,000 that traversed the NEP last year, laden (IIRC) with gas condensate or some such. Most of the vessels were built ice-ready, and most had icebreaker support at least available (even if, as in the case of the Desgagnes, it wasn’t actually used.)

    However, that number is going to rise considerably, if this story is any indication:

    http://www.barentsobserver.com/preparing-for-next-years-northern-sea-route-season.4832790-16175.html

    Comment by Kevin McKinney — 20 Jul 2011 @ 5:26 PM

  52. I understand the westerly winds are caused by the temperature differential between the Poles and the Tropics. If the Arctic Sea Ice disappears in Summer will this cause them to weaken or disapear?

    Comment by DP — 20 Jul 2011 @ 5:32 PM

  53. A couple of random thoughts.

    Re #6 (Hunt Janin): It won’t matter at all if this year’s ice extent is a little above or a little below the minimum of 2007 (there’s a lot of noise), except in the realm of public opinion. I believe that is why so many sane people are rooting for a new minimum – they hope it will spur some real action. I am not so sanguine about the hoped-for effect.

    Re #12 (arcticio): The phenomenon of oil companies trying to exploit the newly accessible areas of the arctic for new oil extraction is what’s known as a positive feedback. To be fair, while the oil companies are certainly evil propagandists, they only supply the stuff; we use it.

    Comment by S. Molnar — 20 Jul 2011 @ 5:40 PM

  54. Hi Nick, $49, Good example of more clouds especially in 2011 and also example of ridging from a very Negative Arctic oscillation. There is no such thing has sea ice improving in any way. There are signals,
    as I discuss on my blog, more pertinent signals. Arctic Basin got really cloudy from this time onwards last year. This year there is more ridging against the archipelago. Except for Northern Greenland. The over all image is dying by melting, vanishing old ice. THis extinction itself has huge impacts for ecosystems let alone the climate. The correct way to present sea ice, one word: SOS….

    Comment by wayne davidson — 20 Jul 2011 @ 6:16 PM

  55. @ Stacey:

    Through 2004, there have only been about 100 full transits of the Northwest Passage, starting with Amundson in 1903-1906. These include icebreakers, submarines and warships (known transits, anyway), passenger vessels, sloops, and yachts. There have been two oil tanker transits, both by the SS Manhattan, and these were feasibility studies; the US-flagged tanker was apparently not approved by the Canadian government. In 2008 the Camilla Desgagnés was the first commercial cargo ship in the NWP, and she and another ship returned in 2009. Most of the traffic since 2004 is either icebreakers or yachts (sometimes being chased by icebreakers — the NWP is in Canadian waters, not open seas).

    Commercial traffic is still in an exploratory phase. In order for the NWP to become a shipping lane, it needs to be reliably ice free over a definite period. And Canada can choose to allow or deny ships wanting passage, and regulate it. (The US could similarly put regulations on the Alaskan North Slope.)

    There are fewer known transits of the Northeast Passage, including a huge gap from 1941-1991. The Northeast passage is almost entirely in Russian (formerly Soviet) waters and they may not have been willing to tell the world what they were up to in that era. Also, they may not have let other ships enter their territory. The NEP is generally more navigable (the sea ice is usually thinner than on the Canadian side of the Arctic), and Russian nuclear-powered icebreakers clear the way for their northern Siberian ports to be served.

    As far as the Northeast Passage, shipping lanes could be open sooner, particularly if convoys were escorted by Russian nuclear icebreakers. But were still probably a decade or more away from any regularly scheduled shipping. Commercial industry isn’t going to do this unless they know their ships (and cargo) are safe.

    Institute of the North (www.institutenorth.org) has some materials on the future of Arctic shipping and potential for Arctic commercial activities in general.

    Naval Postgraduate School has an article by Lawson Brigham on the future of Arctic shipping. http://www.nps.edu/Programs/CCS/WebJournal/Article.aspx?ArticleID=67

    Comment by todd arbetter — 20 Jul 2011 @ 6:17 PM

  56. @Tamino: You science and stats dudes do nice work, but… the methods you use do not account for an speeding up of the process, do they? I didn’t see anything in your post that indicates to a math idiot like myself that this is so. I think you’d be close if you could incorporate increasing rate of decline. If you look at this graph at CryosphereToday http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2010.png you will note, eyeballed only, a series of regime changes from 1900 – 1952, 1953 – 1998, 1999 – 2006, and 2007 – present. The slope increases each time.

    @general:

    Some points. In terms of patterns, we should note the ice is not just now at record lows, but was through most of the last calendar year, particularly in the late fall/early winter through to now. This should indicate a generally lower ice volume, and I suspect it does. This echoes the findings of thin, fragmented ice from the observations aboard ship not all that long ago. There was also a finding this spring that the first year ice was some 40 centimeters thinner than previously.

    Let’s add in that most melt happens from the bottom up and the reinforced findings that there is greater infiltration of warmer Atlantic waters than previously known. Add to this the increased runoff from land which is, itself, reinforced by the increasing sizes and extent of thermokarst lakes, which is all affected by… the finding that rapid ice loss is detectable 900 miles inland. Also, i know snow levels were high in the mid-latitudes, but were they also in the areas contiguous to the Arctic Ocean? if so, more snow = more runoff = warmer ocean.

    Add to all this the loss of multi-year ice which is, so far as I can tell, resulting in less static/fast ice which should make the overall ice more mobile and subject to melt as it breaks up, exposing more ice edge, and is more vulnerable to being flushed out of the basin.

    I have also noted, and am seeking info with this point, that much of the ice appearsto be relatively solid, but once a section begins to break up, it looks a lot like cottage cheese. That is, what seems to be relatively solid ice is maybe nothing more than floes glued together with thin ice. This appears to be the case in all areas that begin to break up thus far this year. What I don’t know is, is this normal? I didn’t previously know of the Arctic Terra site, so have no means for comparison:

    As you can see here, each area that begins to melt out ends up looking like the4 areas that already have. http://www.arctic.io/observations/8/2011-07-19/8-N75.876203-W145.631479

    If this is a general condition in the Arctic Ocean, we are, scientifically speaking, in deep doo-doo and should not be surprised at the melting we are seeing given all the other factors listed.

    Another factor might be the length of the melt season as mentioned above. It does seem the minima is trending toward a later time in September. Will we have 49 more days of melt or closer to 56, or even 60-ish?

    Finally, let’s look at those patterns of bifurcation. A recent study reinforced findings from two years ago that tipping points do have patterns that are recognizable.

    1. Wobbles
    2. Increased amplitude of signal
    3. Slowing

    I refer back to the graph I discussed earlier http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2010.png and the increasing slopes over various time periods. One can also eyeball this pattern of a stable period, then some increasingly “chaotic” amplitudes, then a tightening, then a new regime.

    I ask you to observe the entire graph as one long approach to a bifurcation. The period 1900 – 1952 = steady state; 1953 – 1998 = increasing amplitude; 1999 – 2006 = slowing and 2007 – present = all hell breaking loose. in some of the lines you can see this pattern on shorter time scales. This is probably a reach, but this has been bothering me for a couple years.

    I realize I am not offering up numbers, but that is what the rest of you do. I am thankful that I can only look at observations, my own and others’, then try to decipher numbers. I don’t run the risk of the modeling/stats impacting my analysis of observable phenomena rather than informing it. (Not that you all do.) I can’t do a model or stat analysis, but my expectations have been pretty good over the years.

    At this time, I think the weather is too great a variable to be certain we will see a new minimum extent or area, but offer these scenarios. Given the current state of the ice, let me state the obvious:

    A. If weather is strongly supportive of ice loss, a 100% chance of new minimum in volume, and 95% chance of new minimum area and 90% chance of new minimum extent.

    B. If weather is relatively neutral in impact, drop each by ten percent.

    C. If weather is supportive of ice retention, perhaps a 60% chance of new minimum in volume, and 50% chance of new minimum area and 40% chance of new minimum extent.

    D. If weather is strongly supportive of ice retention, perhaps a 45% chance of new minimum in volume, and 35% chance of new minimum area and 25% chance of new minimum extent.

    I think the ice, overall, is less healthy than most think it is. I think our instruments are not recognizing differences at a high enough resolution causing us to still overestimate the health of the ice. In other words, as stated earlier, there may be lots of thin ice gluing together older ice. Cottage cheese.

    reCAPTCHA: Gorfanus, Youltai – sounds like Genghis mated with a Roman.

    Comment by ccpo — 20 Jul 2011 @ 6:23 PM

  57. @S. Molnar — 20 Jul 2011 @ 5:40 PM
    To be fair, while the oil companies are certainly evil propagandists, they only supply the stuff; we use it.

    Not quite accurate: they bought up and tore out mass transit, successfully lobbied for roads over rail, successfully avoided higher fuel standards decades after they could have made major improvements (non-US makers have for decades) and have successfully been subsidized all along. Among other things.

    Advertising does have an affect.

    @49 Nick Barnes

    You are using a far too limited set of data. Where and when the ice melts each season is a very noisy data set. I know of only one positive bit of data to suggest optimism: the new ice mass data suggesting greater thickness than I would have guessed. (I addressed that above.) All else suggests a new minimum mass, at least. See my post above.

    Comment by ccpo — 20 Jul 2011 @ 6:41 PM

  58. It won’t matter at all if this year’s ice extent is a little above or a little below the minimum of 2007 (there’s a lot of noise), except in the realm of public opinion. I believe that is why so many sane people are rooting for a new minimum – they hope it will spur some real action. I am not so sanguine about the hoped-for effect.

    Indeed. If 5-figure death statistics in a European heat wave don’t move the public’s meter, a little missing sea ice will hardly make it quiver. The deniosphere will regurgitate its standard “Satellite records only go back to 1979!!!” response, and the beat will go on.

    Would the sudden slide of the Greenland ice sheet into the sea do it? I’d give that a “maybe”. Would such an event abash A. Watts? Not in the least.

    Comment by Adam R. — 20 Jul 2011 @ 7:08 PM

  59. One further observation, based on recent data and trends. Looking at this chart http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.recent.arctic.png we see the current anomaly divergence/anomaly is @1.5 M km. measuring from this chart for the same time the past two years, the difference was closer to @1.1M km. Scary is that the divergence only increases into September. If the ratios hold, we could be looking at a difference of 2M km +/- 200k km.

    We’d possibly see 2.8M km.

    Comment by ccpo — 20 Jul 2011 @ 7:18 PM

  60. Re #57 (ccpo): Good point. As a former resident of Los Angeles, where an oil company destroyed the excellent trolley system (I believe it was by buying politicians, not the transit system itself – apparently that was cheaper), I should have been more restrained in my half-hearted defense of the perpetrators.

    Comment by S. Molnar — 20 Jul 2011 @ 7:28 PM

  61. #51, Yes ignorant of me, Canadian Arctic shipping companies deliver goods to dozens of Arctic communities every summer fall seasons ( I suppose in millions of tons) , in abnormally shifting schedules, with earlier and later in the year deliveries, they usually do not need icebreaker escorts. But the icebreakers are always strategically located throughout the duration of the shipping season.

    Comment by wayne davidson — 20 Jul 2011 @ 9:08 PM

  62. @Kevin, @Lennart.
    Extrapolating an exponential forward in time is very uncertain. For any physical system with a linear instability, the amplitude is linear only until nonlinear effects start to become important. Lennart’s comment is an example of one possible limiting factor.

    Comment by Thomas — 20 Jul 2011 @ 9:40 PM

  63. “Will we have 49 more days of melt or closer to 56, or even 60-ish?”

    The switch from mostly (or all) light to mostly (or all) light is surprisingly quick. I think that may be a fairly strong brake on any tendency for the melt season to stretch much later.

    Comment by Kevin McKinney — 20 Jul 2011 @ 9:43 PM

  64. @63 Kevin

    Except that 2/3 of melt is apparently from the bottom up, i.e., water temps. I don’t know the physics involved, but it seems to me the key factor for air temps is cold enough to freeze with limited response for colder temps beyond freezing point. Water temps have no upward bound, however, and so will overwhelm the effects of air temps over time allowing longer and longer melt seasons over time, no?

    Am I far off with this line of thinking?

    Comment by ccpo — 20 Jul 2011 @ 11:14 PM

  65. ccpo:

    @Tamino: You science and stats dudes do nice work, but… the methods you use do not account for an speeding up of the process, do they?

    Actually, if you could be bothered to visit Tamino’s article I linked to, and his own link to an update (today), you’d see that yes, the quadratic fit does seem to show an acceleration of ice extent minimums.

    Comment by dhogaza — 20 Jul 2011 @ 11:25 PM

  66. 56, ccpo: @Tamino: You science and stats dudes do nice work, but… the methods you use do not account for an speeding up of the process, do they?

    It’s in the curvature. Follow the links to his work.

    Comment by Septic Matthew — 20 Jul 2011 @ 11:48 PM

  67. “I think that may be a fairly strong brake on any tendency for the melt season to stretch much later” though the thick clouds + warmish currents flowing in the area may/will delay the onset of the refreeze by some days/weeks/(dare I say months).

    Comment by jyyh — 21 Jul 2011 @ 1:01 AM

  68. ccpo: Tamino’s model is explicitly quadratic.

    Yes, my data is noisy.

    Comment by Nick Barnes — 21 Jul 2011 @ 1:28 AM

  69. Nick Barnes #50:

    Your comments indicate a lack of understanding of how NSIDC calculates Sea Ice Extent (SIE). Any gridded cell with over 15% Sea Ice Concentration is counted as “Ice Covered”.

    Here is a chart showing NSIDC average SIE for September 2010:

    ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Sep/N_201009_extn.png

    100% of the cells in your 2010 MODIS image above counted as “Ice Covered” in the 2010 Sea Ice Extent.

    In your Comment #18, you refer to SIE in 2008. That year, September Extent was also completely covered in the Central Arctic Basin, so no help there for your argument.

    Let’s cut to the chase – Here is the September 2007 Average SIE:

    ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Sep/N_200709_extn.png

    As anyone can clearly see, loss of SIE in 2007 occurred on the edges of the pack ice, and none at all in the center of the pack, or in the Area covered by your MODIS images.

    Further, you discount the PIOMAS volume data based on how you think melt in the Central Basin should have proceeded. Yet you seem to ignore the actual predictions for Ice Thickness for Summer 2011, from the PIOMAS model itself:

    http://psc.apl.washington.edu/zhang/IDAO/seasonal_outlook.html

    Finally you opine for CryoSat2 data, while completely neglecting NASA’s IceSat Sea Ice volume data. IceSat showed significant thinning from 2003 – 2009. Not surprisingly, the PIOMAS model was validated using IceSat, among other data sources.

    In short, you have selectively chosen Data, then seriously misread and misinterpreted that Data. Since your Methods are suspect, your Conclusions are unreliable.

    Comment by Artful Dodger — 21 Jul 2011 @ 3:49 AM

  70. Arctic summer sea ice projections are for it not to be ice free until 2080 or so. Recent revised estimates say 2030/40. Is this weather or climate?

    Comment by Pete best — 21 Jul 2011 @ 3:50 AM

  71. Artful Dodger: I am well aware of how extent is calculated; I have been patiently explaining it to others here and elsewhere for many years.

    The point I am failing to convey is that the character of the ice, broadly across the arctic, is different this year, in a way which is not conveyed by the measures you espouse. Those two MODIS shots show the difference very clearly, but it can be seen in many other places. Specifically, in 2010 (and in 2006, 7, 8, and 9), the ice was far more broken up, into separate floes clearly distinguishable on MODIS even at the 1km resolution. Separate floes move separately, are prone to breaking up and edge-melting. Separate floes expose the ocean to the air and to wind action, causing increased motion and mixing which in turn accelerate melt. Separate floes are more mobile, and are exported more easily.

    Yes, IceSat was good. The PIOMAS data which I specifically question post-dates IceSat.

    Of course I have “selectively chosen Data”. I have a point to make: that the ice is less broken-up than in previous years. I have selectively chosen data which shows that. Choosing data is the only way to extract information from it. I have not “seriously misread and misinterpreted that Data”, or at least you have not shown that I have done so.

    Certainly my “Conclusions are unreliable”. However, I have at least reached conclusions: I have made my forecast for this September’s minimum. What is yours? State it here, and then let us revisit the question in September, and we will see what we shall see.

    Finally, please be less obnoxious. We are on the same side; I am simply opining that 2011 is going to turn out more like 2008 than like 2007, and giving my reasons for that opinion. If I were going to nitpick as you are nitpicking, I would start by pointing out that I don’t anywhere mention NSIDC (so “how NSIDC calculates Sea Ice Extent” is irrelevant), and that “you opine for CryoSat2 data” is ungrammatical and meaningless. Also, capitalizing Random words makes you Look Silly. So let’s not nitpick, eh?

    Comment by Nick Barnes — 21 Jul 2011 @ 5:21 AM

  72. Northern Sea Route almost open

    I agree with Nick Barnes that the central Arctic looks markedly different from last year, but of course this year we have mainly seen compaction due to a pretty strong Beaufort Gyre, which was totally absent last year around this time.

    We’ve got some lows stirring things up at the moment. Maybe next week we’ll start seeing holes in the central ice pack.

    Comment by Neven — 21 Jul 2011 @ 5:41 AM

  73. #64, 67–

    Well, in the long term, yes, warmer water will overwhelm cold air. Presumably that’s why that one study (the citation for which I’ve lost, darn it) found a summer-free Arctic to be unstable. In their runs, a summer ice-free Arctic led to a perenially ice-free Arctic.

    However, in the present regime the water isn’t all *that* warm yet, and the radiative forcing is pretty strong. jyyh is right about the clouds; they have a very strong effect, according to this study of the end of the 2008 melt season:

    http://epic.awi.de/Publications/Sed2010a.pdf

    (h/t to the Artful Dodger, who first posted this link to Neven’s Sea Ice Blog, IIRC)

    “Freeze-up progression was enhanced by a combination of increasing solar zenith angles and surface albedo, while inhibited by a large, positive surface cloud forcing until a new air-mass with considerably less cloudiness advected over the experiment area.”

    But that said, it seems unlikely that we’re going to see “months” of unrelieved cloud in the Arctic any time soon.

    Comment by Kevin McKinney — 21 Jul 2011 @ 6:07 AM

  74. @ Nick Barnes #50

    I had a look at that part of the Arctic around this date in 2007.As you can see, the ice pack was pretty compact too back then. Last year was pretty spectacular in that sense, but if you zoom in on that part of the central ice pack North of the Canadian Archipelago for this year, you’ll see there is a lot of latent hole-potential. All it needs is some diverging winds, and it’ll look like 2010 in no time.

    It is something to keep an eye on, but IMO not necessarily an impediment to a new record low.

    Comment by Neven — 21 Jul 2011 @ 6:15 AM

  75. 2011/07/20 Realclimate.org
    @lawrence coleman

    Yes, in September we can expect a situation like in 2007. The chances are fifty-fifty. You can follow our latest prediction on http://icdc.zmaw.de/cryosphere.html?&L=1

    Regarding the longer time scale it is illustrative to see the recent decrease in the context of the variability of the September sea ice extent over the last Millennium as simulated by a comprehensive Earth system model:

    http://www.wissenslogs.de/wblogs/gallery/16/millennium_eis.jpg

    http://www.wissenslogs.de/wblogs/blog/klimalounge/mechanismen/2011-02-11/kipp-punkte-in-der-arktis” (reference)

    However, we have to be very careful with the interpretation of the model results since the simulated decrease happens 30 years

    Comment by Lars Kaleschke — 21 Jul 2011 @ 6:35 AM

  76. The strong anticyclone over the Beaufort Sea that had been dominating
    the weather over the Arctic Ocean has definitely broken down, take a look at the analysis charts from the Canadian Meteorological Center http://www.weatheroffice.gc.ca/analysis/index_e.html. In response, the ice loss
    rate seems to be slowing down. While this change towards a more cyclonic pattern in mid summer is quite typical, recent years have seen greater dominance of the
    high-pressure pattern that promotes rapid summer ice loss. We’ll just have to wait and see what happens, weather-wise, over the remainder of the summer. On the other hand, old relationships between weather patterns and ice conditions don’t seem to be holding up that well anymore. Case in point, last winter we had a strongly negative Arctic Oscillation pattern which by conventional wisdom should have favored retention of ice the following summer. Instead we ended up third lowest on record.

    Comment by Mark Serreze — 21 Jul 2011 @ 8:37 AM

  77. One could expect the curves of successive years shifting en masse – with noise added of course – downwards. But instead there seems to be a bunching in May-June and in Nov-Dec. Is this an artifact?

    Comment by jimvj — 21 Jul 2011 @ 8:45 AM

  78. @dhogaza, Septic, Nick:

    Thanks for the replies, but “quadratic fit” doesn’t mean anything to me. I’ve been quite clear on not having math skills.

    If you mean to say that a quadratic fit somehow mathematically creates an accelerating function, OK.

    Oh, images indicate the Northeast passage is open as of 7/21.

    http://www.arctic.io/observations/8/2011-07-21/8-N71.52674-E152.298268

    http://www.arctic.io/observations/8/2011-07-21/8-N72.280536-E145.302858

    You heard it here first!

    ;)

    Comment by ccpo — 21 Jul 2011 @ 8:55 AM

  79. ccpo@78:

    If you mean to say that a quadratic fit somehow mathematically creates an accelerating function, OK.

    Yes, exactly, it does. A quadratic function has constant ‘acceleration’ (second derivative).

    Comment by Nick Barnes — 21 Jul 2011 @ 9:23 AM

  80. #77–

    Well, in my humble (but probably insufficiently so, or I’d keep my mouth shut) opinion, it’s not likely an artifact.

    Rates of change in various Arctic parameters are not uniform across the seasons–temperature change, for instance, is greatest in winter, while I believe the decline in ice extent is greatest for summer. So it doesn’t seem a stretch to think that variability can vary, too–which would show up as the ‘bunching’ in the graphs that you remark upon.

    Additionally, there may be negative feedbacks that are especially effective during the transitional seasons. For instance, open expanses of water in the high Arctic in October are apt to freeze rapidly, so the more open water, the more opportunity for rapid gains in sea ice area/extent. By this logic, especially low minima may tend to be followed by especially rapid ice growth–though of course, that ice will be of the most fragile sort.

    The same logic could apply in spring to the case where there is widespread thin ice–it represents an opportunity for rapid declines.

    Come to think of it, this last is rather reminiscent of what we’ve actually been seeing over the last couple of seasons, isn’t it? Rapid gains (like the ‘double hump’ in extent accompanying the very late maximum of ’10) and rapid losses (like the record melt rates we’ve seen the last couple of months)?

    Comment by Kevin McKinney — 21 Jul 2011 @ 9:37 AM

  81. Adam R. wrote: “If 5-figure death statistics in a European heat wave don’t move the public’s meter …”

    The European heat wave arguably did have an important impact on public opinion about global warming — in Europe.

    If the USA experiences 5-figure death statistics from a heat wave, perhaps it will wake some people up.

    On the other hand, more than 30,000 people die every year in car accidents in the USA, and this is accepted as a cost of “enjoying” our auto-centric “lifestyle”, so who knows.

    Comment by SecularAnimist — 21 Jul 2011 @ 9:56 AM

  82. Sorry — that graph is not at all impressive. I would certainly not use it to argue climate change with anybody.

    [Response: Not sure what you are referring to, but if you want cleaner graphs showing the trends, try NSIDC or Cryosphere Today. - gavin]

    Comment by john burgeson — 21 Jul 2011 @ 11:04 AM

  83. @kevin: indeed, there is typically a pulse of heat from the oceans and land as freezing takes place in the fall. As you noted, the later this happens, the later energy is being added to the atmosphere from the ocean and land… thus pushing freeze back even more, just as we saw with areas of Canada not freezing up till December? No?

    Comment by ccpo — 21 Jul 2011 @ 11:12 AM

  84. > low minima may tend to be followed by especially rapid ice growth ….
    > widespread thin ice–it represents an opportunity for rapid declines.

    Eli remarked on this at his blog — seeing the annual cycle emerge in recent years.

    Comment by Hank Roberts — 21 Jul 2011 @ 11:21 AM

  85. Here is a graph of arctic sea ice extent today compared to (what it used to be plus or minus two standard deviations). We are well outside of 2 SD range.

    Comment by Pete Dunkelberg — 21 Jul 2011 @ 12:32 PM

  86. #35 Check out the atmosphereic methane concentration reported by NOAA each year in September. If number 4 in your scenario happens, it will surely show up in this time series.

    It rose steadily until the mid 90s but was flat 1995-2005. It appears to have begun to increase slightly again in the last two years. See Figure 2 at http://www.esrl.noaa.gov/gmd/aggi/

    You can also get underlying data methane concentration at specific sites such as Barrow AL.

    Comment by 350limit — 21 Jul 2011 @ 1:30 PM

  87. john burgeson:

    Sorry — that graph is not at all impressive. I would certainly not use it to argue climate change with anybody.

    Well, it only covers a small number of years.

    This one is more impressive if you want to argue climate change.

    The grey band is +/- 2 std deviations, as you can see we’re between 4 and 5 standard deviations from the 1979-2000 norm.

    I’m sure you know what that implies …

    Comment by dhogaza — 21 Jul 2011 @ 1:46 PM

  88. jimvj @77 asks a question that has puzzled me.

    Why do the ice extent anomalies lessen as the ice forms and then again as it melts? If the measurements were taken at these points it would show very little variation and a much better projection year on year as other factors like wind and currents change.

    I’d be interested to hear resonses.
    Thank you

    Comment by Titus — 21 Jul 2011 @ 3:55 PM

  89. @77/@88 Look at the shape of the Arctic Ocean. You have a wide central expanse, but at lower latitudes it’s mostly land – the only open areas of water are the Bering Sea par the strait and the Greenland Sea past Fram strait. As ice spreads outwards from the Pole during freeze-up (and retreats towards it during melt), you hit a point where the central basin is full, and further north/south expansion or contraction of the frozen zone doesn’t actually change the extent much at all. This is what leads to the “bunching” of the melt trajectories in May / November.

    Comment by Peter Ellis — 21 Jul 2011 @ 5:05 PM

  90. All eyes on Laptev Sea. which traditionally had a barrier of ice preventing a mass exodus in Fram strait.
    If this vanishes, as I wrote before, September 2007 will look like a lot of ice. Already Fram strait is overwhelmed with pack ice:

    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.5.html

    above normal anomaly as if its winter.

    Comment by wayne davidson — 21 Jul 2011 @ 5:45 PM

  91. #76 , As Mark wrote, a break is in place for ice flows, the low forecasted over the Laptev area should give a short reprieve, whether long enough to slow down current ice momentum remains to be seen and also a possible secondary revealing look over Northern Greenland…

    Comment by wayne davidson — 21 Jul 2011 @ 5:55 PM

  92. Lou Grinzo made a comment very early on in this thread regarding this chart at Neven’s site. Lou said that he thought the curves would flatten out as we neared zero due to there being more multi year ice.

    That made me think, what about the actual quality of the ice as it melts year to year? I remember watching one of Dr Barber’s lectures online and he was talking about how the quality of the ice was very poor as they sailed past where they thought they should be encountering solid ice. So, my question is, as we move closer to summer ice free conditions is the quality of the ice going to play a role in how quickly it disappears?

    The implication being, potentially is the trend going to continue that quadratic curve where we have more of a crash landing at zero rather than a soft landing like Lou suggests might happen?

    Comment by Rob Honeycutt — 21 Jul 2011 @ 5:57 PM

  93. Question: I saw this mentioned here in comments maybe a year ago but I don’t remember the answer. As the artic ice and antartic ice slowly go away (through melting and evaporation) would that not at first temporarily cool the planet, kind of like the way that a swamp cooler works, by putting cool moist air into the atmosphere and into the oceans? But then when the temps begin to equalize and the balancing cool of the pole ice is gone would that not also serve to drive and keep up temperatures?

    [Response: Yes, but it is a very small fraction of the extra heat coming into the system - the vast majority of which is going to heat the oceans. -gavin]

    Comment by Scruff — 21 Jul 2011 @ 6:07 PM

  94. I have started an animation that should capture the coming increase in ice transport through Fram Strait.

    Comment by Neven — 21 Jul 2011 @ 6:21 PM

  95. I’ve updated my Northwest and Northeast passages post. I had called a 50/50 chance of them being open by 7/19 and was close to being half right – by my definition of “open.”

    http://aperfectstormcometh.blogspot.com/2011/07/current-state-of-arctic-sea-ice-laymans_21.html

    Also updated tracking of ice through the Fram Straight. I’m tracking specific bits of ice to get a sense of how quickly ice moves through. Surprisingly, some ice has moved northward! Check out #18.

    http://aperfectstormcometh.blogspot.com/2011/07/tracking-arctic-sea-ice-loss-via-fram.html

    FYI, per Neven’s animation, there’s the previous 42 days of animation year-round at Cryosphere Today, but it’s the whole Arctic:

    Black and white: http://arctic.atmos.uiuc.edu/CT/animate.arctic.bandw.0.html

    High color: http://arctic.atmos.uiuc.edu/CT/animate.arctic.color.0.html

    @Neven: You previously mentioned an ice bridge related to the Laptev and ice transport via the Fram. I cannot track this down. Can you elucidate?

    Comment by ccpo — 21 Jul 2011 @ 8:27 PM

  96. ccpo , ya, for all intentional purposes you are right, when the ice coverage is 40% , that gives 60% open…

    Neven, Key to watch is also Fram Strait, which has enormous winds, at times moving things in any direction fast.

    Comment by wayne davidson — 21 Jul 2011 @ 9:07 PM

  97. Seeing this graph makes me more skeptical than ever. Still “on your side” but confidence level has dropped over the past year.

    [Response: Still not following you... What graph is troubling you? The data is what the data is. - gavin]

    Comment by john burgeson — 22 Jul 2011 @ 11:13 AM

  98. re: #97 john burgeson says: 22 Jul 2011 at 11:13 AM
    There is some info here going back to 1953, which gives a good perspective.
    http://nsidc.org/sotc/sea_ice.html

    Comment by Jathanon — 22 Jul 2011 @ 12:16 PM

  99. The dissociation of sub-sea methane hydrates in the Arctic is not one of my biggest worries. I know it may kick-in if releases are great enough to overwhelm the bacteria that consume the methane before it reaches the surface (See. Elliott et al. [2011],Marine methane cycle simulations for the period of early global warming http://esdtools.lbl.gov/info/hydrate-publications/climate/Elliott_JGRB_2011.pdf)

    But there is a report on http://www.foxnews.com “Mass Extinction Caused by Deadly ‘Earth Burp’” reporting research by Micha Ruhl and others (http://www.foxnews.com/scitech/2011/07/21/mass-extinction-caused-by-earths-burp/).

    This is interesting for two reasons. The first is that it could be scary.

    “A small release of carbon dioxide from volcanism initiated global warming of the atmosphere, increasing temperatures in the oceans,” Ruhl told FoxNews.com. “Methane is stored in the sea floor — it’s a molecule which is caught in some kind of ice structure. As soon as the temperatures got above a certain threshold, the ice melted and that methane was released.” (earlier they mention “over 12,000 gigatons of methane”)

    The second is the tone of the report:

    Ruhl noted that events far back in history when the planet was dramatically different are hardly comparable to the modern world.

    “What we don’t know is what the thresholds are today,” he explained, saying simply that the findings dictate further study, not panic.

    I’m past panicking but should I try to be scared?

    Is it too tenuous to present to policy makers?

    Comment by Geoff Beacon — 22 Jul 2011 @ 2:16 PM

  100. John Burgeson:

    Seeing this graph makes me more skeptical than ever. Still “on your side” but confidence level has dropped over the past year.

    Hmmm, on that graph the minimum sea ice extent for the years 2007-2010 are each lower than any of the years 2002-2006. And currently 2011 is ahead of 2007 (reached 7M km^2 earlier than any other year).

    How does this make you “more skeptical”?

    So arctic sea ice extent somewhere between 4 and 5 std deviations from the 1979-2000 mean (as shown on the NSIDC graph Gavin and I linked) makes you more skeptical?

    What’s it going to take? 10 std devs?

    Does this graph make you more skeptical, too?

    What is there here to increase your skepiticism? Please explain your rationale.

    Comment by dhogaza — 22 Jul 2011 @ 2:24 PM

  101. John, seeing a picture doesn’t mean much — what matters is understanding the facts behind the picture so you can interpret it. You’re probably having the common reaction to seeing a chart you don’t understand — “it’s spaghetti” — right?

    But what matters is where the longterm average is and how the world pictured is changing over time.

    You can’t see those in the picture, only in your own underststanding when you attain that.

    Comment by Hank Roberts — 22 Jul 2011 @ 2:50 PM

  102. John @ 97… You have to look at the numbers on the chart. Sept min for 2003 is ~6 million square km. The Sept min for 2007 is ~4 million square km. That’s a 30% loss of min sea ice extent in only a few years.

    Still skeptical?

    Comment by Rob Honeycutt — 22 Jul 2011 @ 3:38 PM

  103. Until Burgeson tells us why he’s more skeptical, we can’t target our arguments very well.

    Maybe he is skeptical because he doesn’t see a trend in the data, or because he doesn’t think the trend is alarming. That one is easy to address (for example, showing the NSIDC September monthly averages at http://nsidc.org/images/arcticseaicenews/20101004_Figure3.png), and seems to be the approach people above have hit on. (whether the trend is alarming is a value judgment, of course).

    But maybe he is more skeptical because he thinks that Arctic ice retreat isn’t a good measure of global warming because he believes it is all due to, say, PDO changes or BC deposition or something else not-GHG-related. That would require a different discussion. I would be very very surprised if GHGs weren’t the main driving force, but there is definitely room for other influences, and I don’t know of a good one-stop-shop that attempts to do the attribution.

    Or maybe he is skeptical because the record starts in 1979, and he’s one of those people who believe that 1979 is cherry-picked as a peak. So we’d point him to a longer reconstruction which shows that ice going back to 1953 was higher than 1979: http://nsidc.org/icelights/files/2010/11/mean_anomaly_1953-2010.png.

    etc. So, Burgy, which one is it?

    -M

    Comment by M — 22 Jul 2011 @ 4:01 PM

  104. The research by Micha Ruhl et al from the University of Copenhagen, published in Science and discussed above by Geoff Beacon in comment currently numbered 99, is reported in more detail at PhysOrg.com:

    http://www.physorg.com/news/2011-07-paleoecologists-mass-extinction-due-huge.html

    Excerpt:

    Prior to this research, most scientists have believed that the sudden extinction of nearly half of all life forms on the planet was due solely to the emissions from volcanic eruptions that were occurring in what was to become the Atlantic Ocean. Ruhl et al contend that instead, what happened, was that the small amount of atmospheric heating that occurred due to the exhaust from the volcanoes, caused the oceans to warm as well, leading to the melting of ice crystals at the bottom of the sea that were holding on to methane created by the millions of years of decomposing sea life. When the ice crystals melted, methane was released, which in turn caused the planet to warm even more, which led to more methane release in a chain reaction, that Ruhl says, was the real reason for the mass extinction that led to the next phase in world history, the rise of dinosaurs …

    This new research, though dire sounding, may or may not have implications for modern Earth. While it is true that humans have pumped significant amounts of carbon into the atmosphere, amounts that are approaching what Ruhl and his team say led to the earlier methane release, it doesn’t necessarily mean we are on the same path, because as Ruhl points out, things are much different today, the very structure of the planet has changed so much that it would be impossible to transfer what might have been learned about events in Earth’s history 200 million years ago, to what is going on today.

    Comment by SecularAnimist — 22 Jul 2011 @ 4:18 PM

  105. Further to #102
    It’s not just the Extent that’s shrinking. The thickness is down as well. While PIOMAS is but a model, the inputs into it are real enough. Last year the PIOMAS anomaly bottomed out sometime in early June (I can’t be sure on the date – the POIMAS data page on their site is devoid of data here in UK). This year there is still no sign of bottoming out as of 30 June. All round, things look bad for summer ice.

    Comment by MARodger — 22 Jul 2011 @ 4:44 PM

  106. John Burgeson – “Still “on your side” but confidence level has dropped over the past year.”

    Really? Really?!?!? Here’s the Climate Change section from Burgeson’s website…

    “Several class members are concerned about the global warming controversy. The following appears below in partial response to this. I claim no particular expertise in this matter.

    Is global warming real? Most scientists think so, although the evidence to date is scanty. Some think not. A Google search on global warming will turn up both kinds. Below are links (external) to some of the more controversial debates:

    A view from a well known scientist [Richard Lindzen] who believes there is no problem
    A very controversial debate on environmentalism
    Bjorn Lomborg’s web site on the controversy

    An essay on emergent teleology, by Dr. Robert Koons
    Bjorn Lomberg’s home page”

    So, he links to Christian philosopher Dr Robert Koons, 3 different pages related to and supportive of Bjorn Lomborg (including Lomborg’s site) and to a Richard Lindzen article at Cato Institute’s website. “On your side…” Puh-leaze….

    Comment by Joe Cushley — 22 Jul 2011 @ 8:16 PM

  107. Would be nice to see previous accuracy of models, Statistical and Heuristics in prediction.
    Can we have such data?

    Seems that someone who has been right in the past has more chances to be right in the future.

    Comment by PAM — 22 Jul 2011 @ 9:38 PM

  108. The following is from a few notes I have about the Barstovian/Luisian, a particular slice of the Miocene that I ma interested in.

    Below find a reconstruction of the North and South America c15Ma, the peak of the Middle Miocene Climate Optimum (MMCO), courtesy of Ronald Clyde Blakey of Northern Arizona University (although Clarence A Hall is said to have the most accurate – “palinspastic” representations). Note the lack of Arctic ice and the continental margins underwater. The global average temps are said to have been about 18.4 degrees C (about 65 F), 3 degrees hotter than today (caused by increased CO2 in the atmosphere) and within IPCC predictions for GW.
    The late great Daniel Axelrod said that an average temp of 14 degrees C is “ideal equable climate”.

    Hot and humid, Lots of mosquitos and ticks I suspect. Outer coaster waters down to about 30 degrees latitude are described by Clarence Hall as being “warm temperate” (temps: 23-25 celsius, 73-77 Farenheit) for for 7.2 months of the year. The waters below 30 degrees latitude and the inland seas are called “outer tropical” (temps: 25-27 C, 77-80+ F) for 9.4 months of the year. The coastal water temps are analogous to those between Pt. Conception and “Bahia Magdalena, Baja Calif Sur Mexico”. Peak warming from the Middle Miocene Climate Optimum occurred about 17 mya to 14.5 Ma, “considered generally to be the warmest period in Earth’s history within the past 25 million years”.

    http://eas.unl.edu/~tfrank/History%20on%20the%20Rocks/Nebraska%20Geology/Cenozoic/cenozoic%20web/2/Timescale_files/Miocene%252015ma.jpg

    Comment by Ron R. — 22 Jul 2011 @ 11:48 PM

  109. Todd @55: Some additional info on using the Northern Sea Route (a.k.a. NE passage)for commercial traffic.

    http://russia-briefing.com/news/russians-to-send-oil-to-china-via-northern-sea-route.html/

    This is serious business. Shipping appears to be expanding despite of evident shortcomings of services in the area. Large tonnage bulk carriers/tankers are experimented with. The current market appears to be for carrying gas condensate from some Russian plant or Swedish iron ore (via a Norwegian port) to industries in Northern China.

    Icebreaker escorts are apparently required, for various reasons. The big ships are not built for use in icefields – surprises are still possible. Navigation and other services (i.e. search and rescue) in the area are not yet fully developed so a support vessel nearby is justified. Service charges appear to be modeled after the Suez canal costs, but leaving the benefit of a shorter transit time mostly to the ship operator (a good incentive). There is also the issue of piracy on the southern alternative.

    A long term prospect might be opening up major coal deposits on the Alaskan North Slope. This resource just might compete with Australian coal that is currently powering Europe. Some feasibility studies were carried out about 15 years ago.

    Comment by Pekka Kostamo — 23 Jul 2011 @ 1:32 AM

  110. PAM 107,

    Try here:

    http://bartonpaullevenson.com/ModelsReliable.html

    Comment by Barton Paul Levenson — 23 Jul 2011 @ 4:31 AM

  111. A new University of Arizona study has concluded that during the last interglacial warming period 100+ky ago thermal expansion of sea water contributed very little to sea level rise which was in the ballpark area of 8metres. Only abut 40cms is contributed to thermal rise. Disturbingly ony 0.7C mean surface temp rise above today’s level locked in this cycle. Cause then was the earth’s orbit relative to the sun causing more pronounced seasonal variablty..thus winters were colder and summers hotter. Thus it was a long time coming but when the warming induced +ve loops became too severe the greenland and antarctic ice sheets melted rapidly causing the 8m rise n a short space of time. They also found that glacial retreat lags significantly behind warming ocean surface temps and that ocean surface temps lags significantly behind atmospheric warming. Thus the extent of inertia in the system is truly awesome. The situation today is worse because in the last interglacial period the temp incease was by largely hotter summers offset against slightly cooler winters..now we have significant atmospheric warming irrespective of what season it is. So the fact is – even if we were to miraculously stop carbon emmissions tomorrow we are still locked in to centuries of global warming and sea level rise which in all liklihood will eclipse the 8m of the last I.G.P. Question: does anyone have a rough idea how long it will take to raise the mean ocean surface temp by a further 0.7C based on a business as usual scenario? Taking into account elevated rates of thermohaline mixing due to more hurricanes/water spouts. Feedback on this will be much welcomed.

    Comment by Lawrence Coleman — 23 Jul 2011 @ 5:40 AM

  112. Burgie,
    OK, ‘splain me this. How does precipitous decline of Arctic sea ice toward what could be unprecedented levels make you more skeptical?

    Burgie, this is science. It’s just about where the evidence points. There are no “sides”. If you are taking sides, you aren’t doing science. If you have evidence that places serious doubt that the most successful theory of Earth’s climate is correct, produce it. If not, maybe you should pay more attention to the evidence and less to persuasive idiots who cherrypick evidence as a framework to support their lies.

    Comment by Ray Ladbury — 23 Jul 2011 @ 5:59 AM

  113. Q.19 Lou Grinzo. Good point! I remember a few years back when it was possible to sail a boat and have a swim at 0degN in August. It hit the headlines for while and then was promptly forgotten by most. People have incredibly short memories!. I dont think it’s possible to shock people any more. We tend to blur fiction with reality with such effortlessness..maybe thanks to all the shock/horror movies desensitising us to the point of catatonic stupor. Even if it were still possible to reverse global warming within he next 10 years and preserve the planet for future generations of life, no-one would bother doing it..heaven forbid our economic bottom line could wobble a bit. I’ve given up with trying to educate people..the tide of denial and lethargy is way to strong to swim against.

    Comment by Lawrence Coleman — 23 Jul 2011 @ 6:02 AM

  114. @ SecularAnimist 104

    Are you implying without saying that there is no cause to worry. You quote Ruhl et.al.

    … caused the oceans to warm as well, leading to the melting of ice crystals at the bottom of the sea that were holding on to methane created by the millions of years of decomposing sea life. When the ice crystals melted, methane was released, which in turn caused the planet to warm even more ”

    OK, now we have warming oceans. Now we have lots of sub-sea methane hydrate – just like then.

    It disassociated then. It’s beginning to dissociate now. Eliott et.al. have described a mechanism by which methane can reach the surface and escape to to the atmosphere.

    So Ruhl et.al. say “it doesn’t necessarily mean we are on the same path” because “things are much different today”. That only means we might not be on the same path, or to make a rational reconstruction, that we might not be on a similar path – we cannot be exactly on the same path. So does anyone have a meaningful measure of similarity? What parameters would you put in a similarity function?

    I suspect that Ruhl’s comments about “different today” are timid waffle of the I-am-a-scientist-I-need-to-be-99%-certain-before-commenting type.

    We don’t live in a world of certainty.

    SecularAnimist, put implication aside, just tell me your call.

    Comment by Geoff Beacon — 23 Jul 2011 @ 9:17 AM

  115. Spaghetti plots like JAXA’s can be confusing. There isn’t enough data to show a clear time progression, but there is too much data to be able to see all the individual years well.

    I tried a similar plot using the longer PIOMAS dataset, using heat mapping to illustrate the change over time.

    Total Arctic Ice Volume by Day of Year

    What do you think?

    Comment by Didactylos — 23 Jul 2011 @ 11:27 AM

  116. I obviously touched off a spark when Ray Ladbury posted:

    “112.Burgie,
    OK, ‘splain me this. How does precipitous decline of Arctic sea ice toward what could be unprecedented levels make you more skeptical? ”

    Obviously, it does not. It is simply not persuasive to most people I talk with (non-scientists).

    “Burgie, this is science. It’s just about where the evidence points.”

    It’s “Burgy”. And I agree w/ the science, as far as I understand it. Once again, it is not persuasive to most people.

    “There are no “sides”.”

    Of course there are. And there are shrill voices on both sides. Many of them are on the comments on this site. Shrill voices turn people off.

    “If you are taking sides, you aren’t doing science.”

    I make no claim to “doing science” on this issue; I am not qualified.

    “If you have evidence that places serious doubt that the most successful theory of Earth’s climate is correct, produce it. If not, maybe you should pay more attention to the evidence and less to persuasive idiots who cherrypick evidence as a framework to support their lies.”

    I read some of the denialist stuff from time to time. It is not at ALL persuasive. I have read several of the more scolarly books on CC, Weart, for instance. But these books do not impress the ordinary non-scientist.

    Someone pointed out that I have some denialist apers on my website. Yes, I have, mostly put there years ago when I first began paying attention to this stuff. My most recent two articles, published in a Colorado newspaper, defended the science.

    My sole and only point is that, after years of trying to sell this, it is failing. Just what would work is beyond my ken. The graph on this article does not help.

    Comment by john burgeson — 23 Jul 2011 @ 11:48 AM

  117. John, the chart isn’t the argument, and incomprehension isn’t a refutation.

    The chart’s just a picture of numbers you need to understand to explain.

    Robert Grumbine’s site teaches this stuff at the high school level, and he has what you need. Try there. http://moregrumbinescience.blogspot.com/

    “you really can get quite far in understanding the world, even climate, by understanding this sort of fundamental….”

    Comment by Hank Roberts — 23 Jul 2011 @ 12:43 PM

  118. I have written a new SIE update. Update conclusion:

    I’m not expecting extent decrease to radically stall like it did last year, but I’m not seeing any century breaks coming about either the coming 5-7 days. I was hoping we’d see more of that fast ice transport toward Fram Strait to see what it would do to the SIE and SIA numbers, but the highs aren’t in the right place. The low off the Siberian coast is pretty strong right now, but is forecasted to weaken in the coming days. It’ll be interesting to see what happens.

    At the moment 2011 is neither fish nor flesh. It could very well be losing its 100K lead to 2007 in the coming week.

    Comment by Neven — 23 Jul 2011 @ 1:38 PM

  119. 116, john burgeson,

    I’d like to point out that after years of trying to “sell” the idea that smoking causes cancer, it really only took hold after decades of smokers died, and the government had intervened to regulate tobacco packaging and advertising, and society had decades to undo prior decade after decade of glamorizing smoking.

    If anyone had been able to really understand the science (and scientists don’t “sell” anything, they just do science) all but the most foolish diehards would have quickly quit smoking. The fact that the tobacco industry was so able to hoodwink an entire population should be a wake-up call to just this sort of thing. That no lesson was learned is frightening.

    The fact that you can’t understand it, see it as a political debate, and understand so little that you can’t even properly decide whom to trust, let alone which aspect of the science is correct, is frightening.

    That you can’t even understand the graphs here well enough to realize how bad the situation has become? Bah…

    I would suggest that you read this: On Experts and Global Warming

    And by the way… your ignorance and inability to separate the wheat from the chaff, along with many others like you, does not absolve you of responsibility for where this planet heads in the coming decades, or for all of the suffering that results from your inability to decide whom to trust, or else to educate yourself well enough that you know that you can trust yourself.

    Comment by Sphaerica (Bob) — 23 Jul 2011 @ 1:48 PM

  120. I have to agree with Hank that the problem with the chart does not lie with the chart, but with the person looking at it. I find it very persuasive, but, then, I am confident I understand it.

    I am tired or people saying we are talking about the science and the issues the wrong way. This is bull. There are people intentionally casting doubt on the science where doubt is not legitimate; it’s not based in the science, but in their greed and ideology. They are lying. For profit and ideology. THEY are speaking about it “wrong” and are not being held accountable.

    THAT is the problem with the science. Prosecute/sue these people for false testimony before Congress, slander, defamation, via class action suit due to harm to the health and well-being of… everyone… and you may see some change. Or, just call them out. Call them liars because they are. Let them bring it to court; they will lose.

    Let’s stop pretending Willie Soon, e.g., has a different opinion and speak forthrightly: his science is crap and he knows it. He’s not being honest. Monckton’s argument’s are so tortuously poor anyone believing he doesn’t know what he’s saying is utter bullocks is just naive. Same with the lot of them.

    And stop pussyfooting around with what the science means: The increased temperatures ARE affecting weather, ARE creating extremes, are costing lives, Are affecting food production, ARE affecting water supplies… and don’t bother being apologetic about it.

    [Response: No matter how great the temptation, we cannot say things that we have not obtained compelling evidence for. The examples you cite are all in the domain of climate change effects. These require an additional level of understanding beyond just climate change itself--and the level of such evidence varies fairly widely. Everyone needs to keep in mind, that given the current political/social climate, we absolutely cannot afford to say things that are not well supported.--Jim]

    When speaking to an American audience ALWAYS use Fahrenheit. 3(C) doesn’t sound nearly as bad as 5.4(F), e.g. And, scientists, when presenting the science to the public don’t speak as if you are speaking to scientists. Don’t speak of scientific uncertainty, translate it to colloquial uncertainty. E.g., don’t say the signal is “unambiguous,” say the signal is clear, because it is. Don’t say something is significant at a .01 level, say it’s as certain as you waking up tomorrow or the sun rising in the morning. Uncertainty in science is not the same thing as uncertainty to laypeople. The average American does not understand scientific/statistical uncertainty, so don’t talk to them as if they do.

    But, yes, do be polite. We live in a PC world and time after time I see outright lies, deeply insulting comments, etc., met with a smile and “everyone has an opinion” because they are said sweetly while the truth, stated directly and without polish, is treated like it’s a steaming pile of crap or a hissing viper because sounding rude is a mortal sin while being rude/lying is quite acceptable.

    /End rant.

    Comment by ccpo — 23 Jul 2011 @ 2:08 PM

  121. In reference to John Burgeson’s comments on the graph, I personally like the one at Arctic ROOS because it includes a 2-standard deviation gray area. This lets the observer compare this year to least year, as well as seeing how far below the norm all of the recent years fall.

    I like the image Didactylos supplied, as well, although I’d suggest running the colors from blue (older) to red (new) to provide a little more contrast (or, alternately, going from light gray to dark gray, which will draw the eye to the low, while making the distant past seem… distant — if the idea is to “sell” the truth to those out there who only understand marketing, jingles, subliminal advertising and commercials with funny punchlines).

    Separately, the new animated gifs from the Naval Research Laboratory are an outstanding supplement to Crysosphere Today.

    The daily photos from the North Pole Web Cams were also cool, until camera one toppled some weeks back due to melting beneath it, and now camera two has done the same in the past day.

    Comment by Sphaerica (Bob) — 23 Jul 2011 @ 2:09 PM

  122. Burgy,
    It’s pretty simple. Evolution tells us that an organism is equipped with sense organs and processing capability that allow it to survive in its environment, right? Should that environment change or should the organism become impaired so that the organism no longer accurately appraise its environment, it will become extinct, right? It would appear that climate change could well be an existential threat for human civilization, if not for human survival. It would also appear that the fact that humans SUCK at risk assessment and find reality too scary to accept is keeping us–or at least the bottom half of the class–from accepting it.

    Too bad. Maybe what comes after us will be smarter.

    Comment by Ray Ladbury — 23 Jul 2011 @ 2:29 PM

  123. > Didactylos … using heat mapping to illustrate the change over time.

    Excellent.

    Comment by Hank Roberts — 23 Jul 2011 @ 2:37 PM

  124. Peter Ellis @89. Thank you for that explanation. That does make sense.
    Another question that comes to mind when I see these graphs is that in a perfect world: ‘what would the ice extents be’?
    I know from recent history that it has been down as low as the Bay of Biscay and up far enough that folks made hay in Grennland.

    Comment by Titus — 23 Jul 2011 @ 3:02 PM

  125. Peter Ellis @89. Thanks for reply. That makes sense.

    Another question that comes to mind when viewing such graphs is that in a perfect world: ‘what would the extent be’?
    I know that from recent history it has been as low as the Bay of Biscay and far enough back that folks made hay in Greenland.

    Comment by Titus — 23 Jul 2011 @ 3:07 PM

  126. Titus: reference please? I don’t believe you are talking about the past few millennia, because that period has seen relatively stable Arctic ice cover.

    So what does this have to do with “recent history”?

    The Greenland myth is a common misconception, and easily answered. The thing about ice that is thousands of years old is that it can’t disappear one year and reappear the next.

    Comment by Didactylos — 23 Jul 2011 @ 4:18 PM

  127. 81, SecularAnimist: If the USA experiences 5-figure death statistics from a heat wave, perhaps it will wake some people up.

    Deaths in heat waves in the US generally cause a flurry of stories about: the need for more tax-subsidized A/C for the poor or elderly; reminders that more people die in cold waves; reminders that the US had higher death rates and or higher temperatures or both in previous years.

    97, John Burgeson: Seeing this graph makes me more skeptical than ever.

    How does that make any sense? There is a clear continuation of a potentially threatening trend — how can it make you more skeptical? If for some reason you have discredited the trend, all that the graph should do is have no effect. If you give the trend some credit, its continuation ought to increase your concern.

    Comment by Septic Matthew — 23 Jul 2011 @ 4:41 PM

  128. Everyone needs to keep in mind, that given the current political/social climate, we absolutely cannot afford to say things that are not well supported.–Jim

    This is precisely where you are wrong, Jim. The list of things acted on by regulation without them being “proven” is long, indeed. If there was ever a case where we must embrace this, it is this issue. We really have no choice.

    And, really, scientifically well-supported is too high a bar, which is my thesis here. If you and others, as scientists, are reluctant, the pull a little Deep Throat impersonation and find somebody to speak for you.

    [Response: Oh yeah, that will go over well. And I see you are back to your accusatory ways--Jim]

    In, I believe, Cancun, Greg (WonderingMind on YouTube) spoke with scientists privately that were prepping for “life boats”, though they would not say so publicly. The BBC did poll of scientists a couple years ago, anonymous, in which the results were depressing at best in terms of meeting 2C.

    [Response:Well, your previous comment was a rant that shows a lack of understanding of how science does, and does not, work. You are confusing issues. I am not, of course, objecting to taking action, nor am I reluctant to speak about it. I am objecting to using any reasoning, to do so, that does not have strong, documented evidence behind it. That evidence can vary in type. You can't just go running around saying "Heat wave--people are dying--global warming". It's a bit more complex and difficult than that I'm afraid. That people cannot see that any statement deemed less than solid will be quickly jumped on, after all that has happened, is beyond me.--Jim]

    Apologies for OT. Back to the topic at hand.

    Comment by ccpo — 23 Jul 2011 @ 6:06 PM

  129. > spoke with scientists privately that were prepping for
    > “life boats”, though they would not say so publicly

    Those thinking in terms of prepping ‘one big lifeboat’ do speak out, notice.

    Comment by Hank Roberts — 23 Jul 2011 @ 9:57 PM

  130. Everyone needs to keep in mind, that given the current political/social climate, we absolutely cannot afford to say things that are not well supported.–Jim

    The trouble is, Jim,

    [Scientists] cannot say X because it is not well supported”

    becomes

    Scientists say X is loony”.

    You’ve got to do better than that.

    Here’s a question from the exam in Public Relations for Scientists:

    Carbon that is being released from melting Arctic tundra as carbon dioxide and methane.

    The next IPCC report, AR5, will be based on computer models that omit this.

    Please write a press release that could be used by the IPCC to excuse this omission.

    Want to answer it?

    Comment by Geoff Beacon — 23 Jul 2011 @ 10:52 PM

  131. Didactylos #115;

    As an interested layperson, I would second Spaerica’s comment about running the colours from blue (or perhaps green??) to red rather than yellow to red.

    In fact, I would suggest only colour-coding the last 10 years (or any other convenient number) and leaving the rest black. This would allow even a casual glance to notice the dramatic recent trend.

    The other suggestion I have is to really really emphasise the fact that this is a graph with a zero lower bound. I have noticed that an awful lot of graphs you see on TV have similar shapes, because the person producing the graph has used the software to maximise contrast by setting the Y axis bounds to or close to the observational extremes. This is especially true of financial channels; a graph showing a 0.1% move can LOOK exactly the same as a graph showing a 10% move until you check the Y axis value points.

    It’s a great graph, though. For anyone with even high-school statistics it makes the overall decline awfully (in every sense) obvious . . .

    Comment by ozajh — 23 Jul 2011 @ 11:20 PM

  132. Didactylos @126. You ask for evidence.

    Not sure what you’re asking for. The last ice age was about 18k years ago when pack ice was down to Bay of Biscay. You can get that info form a huge pile of historical data. I don’t see much problem with that.

    On the Greenland bit it was certainly more accommodating when they arrived and got steadily worse. We can see their infrastructure revealed as the current ice pack has receeded. So it must have been less than it is now.

    So not following your line of reasoning here.

    And back to my question: “in a perfect (natural) world what would the ice extent be’?

    Comment by Titus — 23 Jul 2011 @ 11:42 PM

  133. Further to my previous comment, the colour coding in the AMSR-E SIE graph at the top of this thread is part way to what I’m talking about (I would have a much darker violet for 2002, a light yellow-green for 2007, and then yellow trending to red for 2008-2011).

    Comment by ozajh — 23 Jul 2011 @ 11:45 PM

  134. > computer models that omit this.

    The omitted “this” needs an associated number to put into models though.

    AR4 lacked any good number for sea level rise, and said so. The missing information got filled in over the following five years; we’ll see a better sea level section from the AR5, presumably.

    Comment by Hank Roberts — 23 Jul 2011 @ 11:57 PM

  135. One could also grant to climate scientists that it is not their exclusive duty, that every graph they produce cries out “global warming!” to every layperson on every level of understanding. It is perfectly legitimate to demonstrate other aspects, even if this sometimes obfuscates trends.

    Very instructive diagram from didactylos, though

    Comment by marcus — 24 Jul 2011 @ 2:22 AM

  136. The two graphs featured in the article are for observing the progress of the 2011 melt. John Burgeson is right: neither show anything about trend.

    That’s no excuse, of course. Plenty of other comments provide links to the graphs showing trend.

    Comment by Didactylos — 24 Jul 2011 @ 4:16 AM

  137. @ Jim Bouldin, I think lessons could be learned from Hugh Hammond Bennett’s approach to the Great Dust Bowl. If only Obama would actually step up to the plate.

    Comment by J Bowers — 24 Jul 2011 @ 8:05 AM

  138. Once again, we’re up against the question of what scientists “can” and “should” say about climate change. It’s about as thorny an issue for scientists as one could imagine, probably equal to the decision of whether to help develop the atomic bomb in the 1940s.

    Over the years I’ve had private e-mail exchanges with a couple of dozen people in which I asked them, on the promise of strict confidentiality, to tell me what they really think our situation is regarding climate and public policy aimed at mitigation and adaptation. There were a few scientists in the group, but most were non-scientists who were deeply involved in the topic of climate or general sustainability. None of them were remotely close to the stereotypical left-wing tree hugger type at least some of you might be imagining right now.

    In almost every case the person admitted to being far more pessimistic than s/he acknowledged in public, sometimes startlingly so. Some of the most conservative, sober people I asked said we’re headed for a Lovelock-esque crash down to a population of 1 or 2 billion by 2100. In not one case was the person more optimistic privately, with the balance of them being too close to call.

    I honestly don’t know what I would advise a scientist friend to do in this regard if asked. The climate mess we’ve created is so immense, with so many timing aspects working against us, that I can’t see how we avoid some horrible outcomes regarding mass numbers of refugees and even mass starvation in some parts of the world, far worse than what’s unfolding right now in the Horn of Africa. But how do you explain that to a politicized, disaffected public that thinks changing light bulbs and recycling paper is “being green”, without sounding like a lunatic? Asking scientists to be brutally honest is asking them to commit career suicide. Perhaps we need many more scientists Hansen’s age and proximity to retirement, who love all the children of the world as much as he loves his grandkids.

    Personally, my view aligns very closely with Bill McKibben’s, as he expressed it in a recent interview: “We’ve already raised the temperature of the planet one degree. We’ve got another degree in the pipeline from carbon we’ve already emitted. What we’re talking about now is whether we’re going to have a difficult, difficult century, or an impossible one. And we may still have enough room to maneuver to affect the outcome of that question.” (I quote this and add my own thoughts here: http://www.grinzo.com/energy/2011/07/18/mckibben-and-determination/ Note the “may” in his last sentence.

    I think we have no choice but to keep fighting as hard as each of us can. And that begins with science — getting our facts right, understanding the insanely complex dynamics of the world and the ramifications of X ppm of CO2 or Y degrees C of warming or Z% increase in acidity of the oceans. But the non-scientists among us (like me) have our own burden. We have to listen to the scientists and their findings, and do everything we can to educate and activate those around us. This requires a balancing act between including the latest “it’s worse than we thought” revelation (and they keep on coming) ad avoiding overselling the facts.

    This is why I ask questions about quadratic fit Arctic ice projections that show zero ice for months just a few years from now. I know just enough about climate science to understand how important such an event would be, if it were to happen.

    To the climate scientists of the world: I cannot thank you enough for your work. Please keep hammering on every part of this huge problem and be as honest in public about what you really think as your comfort zone allows.

    Comment by Lou Grinzo — 24 Jul 2011 @ 8:35 AM

  139. Titus: You are mistaken. Read the link I provided.

    I’m afraid you are the victim of propaganda – ancient Viking propaganda, as well as modern fossil fuel propaganda.

    You seem to be genuinely confused. Greenland has always been accessible by sea in the southern regions. Only the north part is permanently bounded by sea ice. That some parts of Greenland are not covered by the ice cap is undisputed, as is the history of settlements on Greenland. You are falling into the trap of assuming that this means Greenland was warmer then than it is now: that clearly does not follow from the evidence.

    Comment by Didactylos — 24 Jul 2011 @ 9:20 AM

  140. Hank @134

    But policy makers don’t seem to know.

    Perhaps you could point me to some policy makers that understand the omissions of feedback effects in climate models. I spoke to the UK Secretary of State for Energy and Climate Change and he thought that the missing feedback from melting Arctic tundra was solved. Subsequent enquiry seems to have revealed he was wrong.

    You may see my report in Open letter to Chris Huhne

    He also told me he read Real Climate. Perhaps I can encourage him to respond to my last two letters here. The Department is blocking them.

    Comment by Geoff Beacon — 24 Jul 2011 @ 9:34 AM

  141. All right everybody, lighten up.

    But just for ten minutes, then break time’s over. Back on your heads.

    Comment by Pete Dunkelberg — 24 Jul 2011 @ 9:34 AM

  142. Sphaerica (Bob) and ozajh:

    I’m pleased you like the graph. I tried blue->red, but blue and red have much closer brightness levels than yellow and red. When converted to grayscale, blue, red and the intervening hues are almost indistinguishable. It does look nice if you have full colour vision, though!

    I tried putting a line at y=0, but it looks odd. I could extend the y axis into the negative, but that has no physical meaning and also wastes space. So, I’m open to ideas for how to emphasise the zero.

    The suggestion for only colouring the last 10 years is interesting, and I may try that if I have a spare moment. However, one of my goals when creating the graph was to visualise the variance in the early part of the record, in order to make more sense of the 2 SD graph that PIOMAS provided.

    Comment by Didactylos — 24 Jul 2011 @ 9:40 AM

  143. Didactylos @139. Thank you for response.

    Accepting what you say about Greenland I’m still left with my question:
    “in a perfect (natural) world what would the ice extent be’?

    Comment by Titus — 24 Jul 2011 @ 11:38 AM

  144. To understand what is driving the Arctic Ocean it would be desirable to know what drives the Atlantic and Pacific.
    However the current state of knowledge is:
    The nature and origin of the AMO is uncertain, and it remains unknown whether it represents a persistent periodic driver in the climate system, or merely a transient feature.
    The PDO goes through warm and cool phases of the cycle with phases typically lasting about 30 years. It is closely related to the (inverted) SOI / ENSO. The causes of the oscillation are currently unknown.

    Sooner or later the above ‘known unknowns’ will become ‘known knowns’:
    http://www.vukcevic.talktalk.net/AP.htm

    Comment by vukcevic — 24 Jul 2011 @ 12:17 PM

  145. I’ve tried to post this numerous times.

    RE # 120

    Jim Bouldin, maybe your comment to ccpo is a more topical matter than the chart.

    You said to ccpo, “No matter how great the temptation, we cannot say things that we have not obtained compelling evidence for.”

    Well, I look at that chart and see the reason the Northern Alaskan Inuit village of Shishmaref is being destroyed by climate change. It is a community continually inhabited for nearly four thousand years. We have compelling evidence of that fact. Shishmaref, according to the US Corps of Engineers will be completely abandoned within a decade and its 660 inhabitants will be forced to relocate to the streets of Anchorage, Juneau, Fairbanks, and Nome. They will have lost their culture, families, language, and way of live. We have compelling evidence of how American Indians forced off their lands fared in their new resettlements.

    The reason Shishmaref is being destroyed in evident in that chart. Late refreeze allows early winter storm waves to tear at the shoreline. We have compelling evidence of that dynamic.

    Arctic ice meltback has reached a tipping point and Mark Serezze and others who have devoted their professional lives to understanding the mechanics of Arctic melt and freeze have convinced themselves and anyone with half a brain that the changing Arctic is due to warmed ocean and air temperatures.. the Arctic amplification as Mark calls it. We have compelling evidence of that.

    You have devoted your professional life to studying tree rings and try to decipher their story. I can see how you might be reticent to jump out front and say this ponderosa pine or that bristlecone pine (Pinus aristata) or that Coast Redwood (Sequoia sempervirens) each have a story to tell us about changing climates but those rings may be 5 or 6 hundred or 2 thousand years old. Not much of a convincing story of pending chaos for us 7 billion people that the beginning of the 6th extinction is at hand.

    However, plat maps of Shishmaref provided by the State of Alaska since 1980 give graphic proof that about a hundred yards of coast line have been ripped off the Island of Shishmaref and its public school building may soon have to be abandoned. WE have compelling evidence of that.

    So, Jim, you need to look beyond your own work and see the forest, so to speak, and realize we have compelling evidence all around us that climate change is impacting land, people, ecosystems and our future. Take a look at some of the images of Shisharef’s final days and blame that on climate change and dare to tell people, as a scientist, you connected the dots and say, unequivocally, that climate change is destroying the culture and homeland of 660 Inuit inhabitants of Shishmaref Island. Of that, we have compelling evidence.

    [Response: OK, good example from what appears to be a fairly short and simple cause/effect chain, but that's not something I study, so why do you expect me to be on a soapbox about it? And I have a very short fuse with those who say things starting "You need to [do this that or the other]“. I don’t need to do anything, nor do any of us here. When other people have no income and are living out of their truck for many months on end, while still contributing to blogs and trying to write papers in two different fields, then they can advise me of what I “should be” doing OK? I’m aware of much of the evidence of climate change on ecosystems (and no, I have not devoted my professional life to analyzing tree rings–it’s a very small part of what I’ve done), and in fact my first article here was specifically devoted to relating one aspect of tree mortality, to regional hydrological changes, and thence to global climate change. There is also evidence for climatic change effects on phenological events, carbon cycling rates, fire frequency and extent, insect outbreaks, and other things. And then there is also a bunch of evidence for non-climatic factors that affect those very same things, some of which are themselves affected by climate, others not. Your mentioning of the current extinction event is a prime example. It’s a complex world out there. But my point is to not get sucked into any traps of saying things off the cuff. And certainly not under pressure from anyone. And I ain’t yielding on it, for anyone. That’s not how we got to where we are. –Jim]

    Comment by John McCormick — 24 Jul 2011 @ 12:41 PM

  146. 119: Bob Sphaerica discussed John Burgeson’s ignorance.

    I don’t know John Burgeson. I never really noticed him until the other day. After perusing his website for a half hour or so I certainly wouldn’t call him ignorant. He is certainly correct when he says (in 116) that “shrillness” does not work. That being said, it does take the patience of Job to remain calm when you see the same night of the living dead arguments appear over and over and over. As far as I can tell there is no graph what-so-ever that will convince large quantities of people that climate change is going to make life miserable. Maybe to understand why this is we ought to re-read CP Snow’s “Two Cultures”. I think it will take wide spread misery before mankind’s to global warming is concordant with the thread.

    Comment by John E. Pearson — 24 Jul 2011 @ 1:13 PM

  147. typos: I wrote “I think it will take wide spread misery before mankind’s to global warming is concordant with the thread.”

    I meant to write: “I think it will take wide-spread misery before mankind’s response to global warming becomes concordant with the threat.”

    Comment by John E. Pearson — 24 Jul 2011 @ 1:55 PM

  148. Didactylos: How about just plotting the PIOMAS data as a function of time then fitting a straightline to it?

    Comment by John E. Pearson — 24 Jul 2011 @ 2:18 PM

  149. 142, Didactylos,

    This is what I meant:

    Comment by Sphaerica (Bob) — 24 Jul 2011 @ 2:40 PM

  150. (I forgot to fix the key on the image at http://img268.imageshack.us/img268/2674/iammelting.png. It should show gray to black from 1979 to 2010, then 2011 as red).

    Comment by Sphaerica (Bob) — 24 Jul 2011 @ 2:41 PM

  151. 121 Sphaerica (Bob): NRL doesn’t tell me what units they are using. Otherwise, I get the same idea that we had better visit the Arctic while there is still ice to see. What do they mean by 1/12 degrees? The polar web cams make pictures that lack context for me.

    110 Bart Levenson: Thanks for that web page of yours.

    128 & 130 ccpo and Geoff Beacon vs Jim. Well, sort of. Bart Levenson’s prediction is absolutely terrifying as far as I am concerned, and within science. Why not go with that? We are all quite reasonably frustrated and panicky. What to DO? The Arctic melting ice should be plenty of evidence for anybody. There it is, all that water where ice was before. Any 6 year old should be able to see the difference. The phenomenon of denial is absolutely astounding. Is there a sociology blog as good as RC that covers that sort of thing?

    138 Lou Grinzo covers the what to say in the ccpo and Geoff Beacon vs Jim debate. It looks like we all agree. Reality is worse than anything we could imagine or make up. We have to find a way to show the Arctic ice melting to everybody. Arctic ice melting is very easy to see and undeniable. Add some consequences for the rest of the world. It has to be a slick finished production like it came out of Hollywood. The NRL Arctic web cams are not a finished production. It has to be super-easy to understand. It has to be a video with a great sound track. Then put it on Youtube.

    Most people have to have a solution to the problem before they will admit that there is a problem. The video has to say that there is a solution. It doesn’t have to say what.

    Comment by Edward Greisch — 24 Jul 2011 @ 3:01 PM

  152. 152, Edward Greisch,

    Most people have to have a solution to the problem before they will admit that there is a problem.

    In the case of climate change, I firmly believe that the answer is a whole lot of little solutions (behavior changes, like not all commuting at once, or restricting business air travel to what makes sense, more energy efficient buildings, more fuel efficient vehicles, alternative fuel sources, etc., etc.).

    I think a whole lot of little changes will add up to what we need, to the extent that people don’t really even notice (or perhaps like) the difference.

    Unfortunately, that sort of solution — not a dramatic, sweeping change, but rather a whole lot of little, incremental changes — requires that people first admit to the problem, totally and completely, and address it themselves, on a daily basis, in small, incremental ways rather than sitting back and hoping governments or scientists or engineers will somehow solve the problem for them.

    This is what I find most perplexing about deniers, that the very thing that they want to avoid — economic crisis and major lifestyle changes — are almost being forced on us by the unnecessary delay.

    Comment by Sphaerica (Bob) — 24 Jul 2011 @ 3:53 PM

  153. Titus: you asked “in a perfect (natural) world what would the ice extent be?”

    Well, if your definition of “perfect” doesn’t include humanity, then obviously the planet has seen all extremes from snowball earth to zero ice in the distant past.

    But if you think humanity is special, or worth keeping around, then we only know with any certainty of two ice conditions – glacial conditions like the kind you mentioned earlier, for example during the last glacial period, and interglacial conditions, like those we have observed in the modern era (and have been relatively stable for thousands of years). These interglacial conditions are associated with polar ice caps about the size we are used to, before they started to vanish.

    We can be fairly confident about this because while sea level has been significantly lower during glacial periods, it has not been noticeably higher than present for the last million years. Sea ice doesn’t contribute to sea level rise, but the entire cryosphere is sensitive to temperature.

    Comment by Didactylos — 24 Jul 2011 @ 4:14 PM

  154. Edward, 1/12 degrees is just the grid resolution. http://www7320.nrlssc.navy.mil/hycomARC/prologue.html

    Comment by Didactylos — 24 Jul 2011 @ 4:29 PM

  155. ccpo says:
    23 Jul 2011 at 6:06 PM

    [Response: Oh yeah, that will go over well. And I see you are back to your accusatory ways--Jim]

    I have no idea where that is coming from. Who was accused of what? perhaps you feel my suggesting scientists **need** to be more activists is somehow accusatory? If that is your point, I am not attempting to imply any given scientist is not doing what they perceive to be appropriate, but I *am* suggesting this is a time unlike any humanity has faced and that how we handle it will, and must, be different than how we have done things in the past. FYI, it is my opinion this is true of all segments of society, not just scientists.

    That people cannot see that any statement deemed less than solid will be quickly jumped on, after all that has happened, is beyond me.–Jim

    This line of reasoning is easy to understand and is easy to “see.” Per my above comment, it may not be germane any longer. E.g., Annie Leonard, maker of “The Story of Stuff”, made an excellent observation regarding climate that it was time to simply act regardless of the denialists and essentially ignore them to get onto the business of solving problems.

    I think this is a cogent argument. if we simply stop legitimizing denial by not giving it the time of day except to name it and blow past, perhaps that will be more effective than fighting. Of course, this is more true for us lay people. You scientists do need to combat poor science with well-done science to, as you point out, undergird the arguments. But mostly, we need to just blow these people out of the way. Call a lie a lie, bad science bad science, paid hitmen paid hitmen, etc.

    And, no, I don’t understand why we should pretend the heat waves, stronger storms, larger floods, etc., we are experiencing are not affected by climate. As numbers of scientists have pointed out, the overall loading of the system should be noted as impacting events, even if we cannot mathematically or experimentally prove it, because we all know it is true. We have no responsibility to pretend otherwise.

    Why would the following be imprudent (Not based on any real event)?

    “Yes, the record flood and other extreme weather are affected by the rise in temperatures and water vapor since 1900. As a scientist, I hate to say something like that because I cannot draw a line of absolute proof from a given event to the increased temperatures and water vapor. But this is not about the science. Scientists rarely speak of things in terms of absolute certainty. It’s difficult to explain this, but scientific certainty is not the same as risk assessment and policy-making.

    When it comes to climate change, we, as scientists, understand the magnitude of the risk, and it is grave. other issues, in fact virtually all policy decisions, are made without any certainty at all. Climate Change is scientifically understood far more than, say, any discussion of economics or budget, yet, we make budgets all the time. Climate has a far higher chance of very large disruptions to society than, say, the chance your house will burn down or you’ll be severely injured in a car crash. Yet, we protect ourselves from those things.

    The fact is, there is no doubt, in the sense that you, the public thinks of and talks of things, that climate is changing, is heating up, and is already having large impacts on our society. Is the recent heatwave part of climate change? Of course it is because the entire planet is now in a different condition than it used to be. That is completely beyond debate. Don’t let anyone try to convince you otherwise. Those who claim otherwise have been shown to base their opinions on non-scientific issues. The small areas of concern that are raised in legitimate science are acted on and studied when they arise. They always have been.”

    Perhaps you feel this is already being said by enough scientists, but, imo, the way it is spoken by many, perhaps most, scientists publicly is more equivocal than this.

    Again, this is not accusation, it is an appeal to continue to increase the amplitude and frequency of this message.

    My apologies, again. I really expected you to move my “rant” over to unforced variations and didn’t expect people to be continuing this here. I have to admit I’m glad it’s still here.

    Believe me, Jim, I respect the work of all of you and do not mean to sound accusatory. My studies in all other fields and in my chosen avocations/vocations all lead me to believe what I have always said here: time is short. Shorter than most think. I hope to be wrong, but am very afraid I am not.

    Here’s to the long solar minimum actually happening.

    Comment by ccpo — 24 Jul 2011 @ 5:24 PM

  156. @#137 jbowers: “This particular dust storm blotted out the sun over the nations capital, drove grit between the teeth of New Yorkers, and scattered dust on the decks of ships 200 miles out to sea. I suspect that when people along the seaboard of the eastern United States began to taste fresh soil from the plains 2,000 miles away, many of them realized for the first time that somewhere something had gone wrong with the land. It seems to take something like a disaster to awaken people who have been accustomed to great national prosperity, such as ours, to the presence of a national menace. Although we were slowly coming to realize that soil erosion was a major national problem, even before that great dust storm, it took that storm to awaken the nation as a whole to some realization of the menace of erosion.”

    This is what I fear, and why I do make the ask: Please, more scientists speak more forcefully on this issue.

    @145 John McCormick says: So, Jim, you need to look beyond your own work and see the forest, so to speak, and realize we have compelling evidence all around us that climate change is impacting land, people, ecosystems and our future.

    John, an excellent example. And there are so many of them.

    And Jim B. says:

    And I have a very short fuse with those who say things starting “You need to [do this that or the other]“.

    Jim, I sometimes rely on context overmuch and am not a specific as I might be, but it should be fairly clear I at no time meant you personally. perhaps you understand that and actually mean you don’t like it when people tell scientists they “need” to do something. Fair enough.

    However, the use of “need” is conversational and was not really intended to convey an absolute. Thinking about it, though, I find it does need to be an absolute. I realize you, as a scientist, likely have a clearer perspective on climate than I do. Very, very likely.

    The advantage I may have is that my perspective may be more eclectic than yours. For five years I have studied climate and energy… and population… and water… and oceans… and economics… and sustainability… and energy… and water… all in terms of their interactions.

    You may have, too. If so, I have a very hard time understanding why your statements are more circumspect than mine are. I think it would be frightening, indeed, to truly understand what our climate is capable of.

    But I have found that it is the interactions of all the issues that is the problem for that is the true system, not the climate. Climate is but one piece of the puzzle. It is a highly complex puzzle, but the complexity when we add all the other issues to solving the climate challenge is magnitudes greater.

    It is this that I see in my mind. It is this I see when I look at my son. And it is this that compels me to urge the scientists to speak more forcefully. It’s not just climate science, it’s everything. And, yes, i do think we have to draw this conversation around to the full range of interacting issues being part of the discussion much, if not all, of the time. I.e., discussing what to do about climate outside of discussions about energy, water, economics, etc., no longer is a luxury we have.

    Jim says: When other people have no income and are living out of their truck for many months on end, while still contributing to blogs and trying to write papers in two different fields, then they can advise me of what I “should be” doing OK?

    While I don’t write papers, I have spent my savings putting my money where my mouth is; have had my wife run off, kidnapping my son in the process; am about to lose my home; currently have no income, no public assistance, no unemployment insurance and should have the utilities going off soon. I just cut my own hair, believe it or not. (I’m kinda freaked out it looks OK.)

    I am not asking you to do anything I have not already done, and am currently doing.

    Glad to know I’m qualified, tho.

    ;-)

    Enough on this. My apologies.

    Cheers

    Comment by ccpo — 24 Jul 2011 @ 6:15 PM

  157. ccpo, you needn’t offer any apologies. You are speaking for many, if not all those, who believe what the read, hear and see regarding climate change.

    Perhaps Jim is taking this all too personally. But, when he says: That people cannot see that any statement deemed less than solid will be quickly jumped on, after all that has happened, is beyond me.: I find that statement beyond me also. What is really solid are the now, visible and verifiable evidences of climate change impact.

    Yes, we smell the smoke, but we don’t have to wait for the chemical analysis of that smoke to know it is time to call 911 and get to safer ground.

    Comment by John McCormick — 24 Jul 2011 @ 7:02 PM

  158. I was brought around to speaking more forcefully about current weather/climate events after reading an address by Kevin Trenberth to the American Meteorological Society back in January, in honor of Stephen Schneider.
    http://ams.confex.com/ams/91Annual/webprogram/Paper180230.html

    The main point resonated with me: “Moving towards a form of operational real time attribution of climate and weather events is essential, but needs to recognize the shortcomings of models and understanding (or the uncertainties, as Steve would say). Given that global warming is unequivocal, the null hypothesis should be that all weather events are affected by global warming rather than the inane statements along the lines of “of course we cannot attribute any particular weather event to global warming”. That kind of comment is answering the wrong question.

    Comment by John Pollack — 24 Jul 2011 @ 9:07 PM

  159. Didactylos @ 142,

    Thanks for the reply. Looks like we’re posting from different time zones (I am in Australia, hence the blogname) so most of my posts will appear late at night US time.

    I take your point about being interested in the early part of the record. I am more interested in the last decade, since I personally believe the current trend is strong enough to render any SD calculations moot.

    Sphaerica (Bob) @ 150,

    YES. That’s exactly what I was trying to describe earlier, but with the last 10 years coloured instead of just 2011. (And having a grey scale for earlier years is a nice touch.) :-)

    Comment by ozajh — 24 Jul 2011 @ 10:18 PM

  160. 157, John,

    I agree 100% with Jim’s position. Stick to the facts, and to what is proven, not merely suspected.

    The problem does not lie with the scientists, it lies with the politicians. It lies with those who believe in climate change (primarily U.S. democrats) that lack the will to actually make an issue of it. I like Obama as a president, but I’m very disappointed by the lip service he’s given to the issue.

    The other side (primarily U.S. republicans) who are fighting against the issue are of course the most to blame, but it is not the fault of science that they are either blinded or bought out by their own political interests.

    I do hope that I live long enough to (a) know that the problem is being properly addressed and (b) that the people who were on the wrong side of this in the critical years are taken to task for their indefensible position.

    But the problem does not lie with the scientists, either in how or what they communicate. Jim’s position is the only one a scientist can take. I applaud Hansen for taking the stance that he does, but not all of them can do so, and even he must maintain his reputation first as a scientist, and second as an advocate. He does battle, but he does so only with science and what is provable. And certainly, they cannot all take that road, and be as outspoken as he is.

    The day may come when a scientist abandons his profession to play foil to the Moncktons of the world, but I hope it doesn’t come to that. And if it is not going to come to that, pressure should be put not on the scientists but on the politicians, for those who understand the danger to act more aggressively and for those who don’t understand to wake up and admit to the truth of the matter.

    Beating up on the scientists isn’t the answer, and it’s totally undeserved.

    Comment by Sphaerica (Bob) — 24 Jul 2011 @ 10:20 PM

  161. Didactylos @153. Thank you again for reply.

    From what you say; do I understand that we do not have a measure of what the Arctic extent is supposed to be in our current environment?

    I grew up in the 50′s and 60′s and remember that Arctic extent increased quite significantly around the middle of that century. We were also taught that wind and currents had a significant effect. I guess when my generation leaves you will have an easier time getting folks to adopt the current thinking.

    Comment by Titus — 24 Jul 2011 @ 11:34 PM

  162. Sea Ice Volume

    http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice_volume/BPIOMASIceVolumeAnomalyCurrentV2_CY.png?%3C?php%20echo%20time()?

    Comment by Vendicar Decarian — 25 Jul 2011 @ 12:36 AM

  163. 152 Sphaerica (Bob): “I firmly believe that the answer is a whole lot of little solutions (behavior changes, like not all commuting at once, or restricting business air travel to what makes sense, more energy efficient buildings, more fuel efficient vehicles, alternative fuel sources, etc., etc.).”

    Sorry, but that isn’t working so far. It is only creating irritation and a negative attitude toward environmentalism. If you get them angry enough, they will retaliate. Besides that, it is accomplishing nothing. It IS making people think that they are doing their fair share when nothing is being accomplished, another negative. “Believe” is an unscientific word. We have confidence levels, not beliefs.

    The first wedge has to be a big one that the average person never notices, like outlawing power plants that add CO2 to the air.

    “This is what I find most perplexing about deniers, that the very thing that they want to avoid — economic crisis and major lifestyle changes — are almost being forced on us by the unnecessary delay.”

    You are assuming that they are being truthful about their motives. They are not being truthful about anything. Read “The sociopath next door : the ruthless versus the rest of us” by Martha Stout. New York : Broadway Books, 2005. Actually, chaos would be exciting, and they crave excitement in any form, because they care about nothing and nobody.

    We need to make a new semi-political web site and blog, maybe a new political party, because RC wants to stay pure science.

    Didactylos & Titus: The ice extent should be what it was in 1950. Why? Because the 1950s were years of plenty.

    Comment by Edward Greisch — 25 Jul 2011 @ 1:02 AM

  164. Hmmm. I’m with Jim on not saying stuff which we don’t have very strong reason to believe to be true. There are a significant number of “greenies” who are ready to believe any old tripe that fits in with their world view. There are an awful lot of “fake” skeptics who are the same with climate science – they will believe any rubbish which they believe disproves AGW.

    Good solid arguments are diminished if followed by unsubstantiated assertions (except in the case of this sentence, despite it being an unsubstantiated assertion).

    Comment by John Brookes — 25 Jul 2011 @ 2:44 AM

  165. Barton 110.

    I really liked your link and it is very interesting recap.
    My comments were more related to Artic Ice estimation.
    As you may know the NSIDC is production a competition between models, statistics and Heuristics to predict summer ice extent.
    In the context of the predictions done by these experts I would like to know:
    Who is the most/least (or order is even better) accurate at the first prediction?

    As they go on doing many prediction, which is the improving in accuracy as time evolves?

    Point is competition is great at first to stimulate all these guys to look fro alternative.
    Now they would probably love to see some statistical measurements of their evolution.
    After the goal is that the team of them is as perfect as possible.

    I have a few concerns with the actual models…

    Which ones has in it a good accuracy fro methane emitted from oceans?
    Methane from pergelisol?

    If we focus on CO2, we can easily measure the impact.
    It is the domino effect that is tough to measure.

    Decomposing all ingredients into separate impacts then rebuild the synergy with modeling seems to be the avenue some must have taken.
    Again, here, I am just a newbie… (may be three posts in here).

    I have some fundamental questions like:
    Is there a model that predict an abrupt climate change?
    Do we have models that can predict the number of cat 3+ hurricanes with 90% degree of certitude?

    Someone must have think about this way before me so it must have been studied.

    My post was too long… So it was identified as Spam.
    I will try to post it in many parts: decompose and rule.

    Comment by PAM — 25 Jul 2011 @ 4:05 AM

  166. Sphaerica (Bob) @160

    I agree 100% with Jim’s position. Stick to the facts, and to what is proven, not merely suspected.

    Is it proven that the models used for the current round of the IPCC negotiations underestimate climate change because they don’t include important feedback mechanisms? I’d say it is.

    What would you say?

    P.S.

    My MP seems to have accepted DECC’s refusal to answer letters. The main question is “Why didn’t the Secretary of State know?” I can’t ask Huhne in person for a month or two. Anyone in the UK got an MP that might help?

    P.P.S

    I’m glad Jim’s closer to the sharp end of this struggle than I am.

    Comment by Geoff Beacon — 25 Jul 2011 @ 4:07 AM

  167. Post 162 seems also to point to information about sea ice volume.
    Intuitively, I do see that the ice cube in my glass is slow to melt at first but the volume seems to follow a kind of logarithmic (exponential or similar) spped of melting.
    Just me looking at the ice cube in my glass… No real science here.
    But if I use this intuition, I would expect that the same could happen in Artic, Groenland and Antartica.
    As we are looking at great volumes, it must take longer to show that the preogression is not linear.
    Now that I have put my questions in context, it is time to ask them:
    - Is the melting of ice following a linear or a logarithmic function?
    - When we had prediction of summer free artic sea in 2050, was it based on a linear progression?
    - Are we starting to see logarithmic (or exponential cqn tell which is the good word but you get the feeling) melting?
    - If such a function exists, what is the prediction for ice free summer: 2020? 2030?
    (I read 2030 but again, I am skeptical, seems all study are underevaluating the progression of this…).

    To me Artic ice is the canary in the mine shaft: really shows the pace we should expect.

    Looking at winter ice is even more interesting.
    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.recent.arctic.png was previously posted.

    What is the trend?
    Between 2010 and 2011, we seemed to have lost about .7MKM2
    How much time should it take to go from 13MKM2 to zero?
    Any estimates? what is the pace since 2007 (after 2007)?
    What is the pace since 1969?

    Comment by PAM — 25 Jul 2011 @ 4:15 AM

  168. Titus, that’s not what I said, and your memory is not reflected by the long-term records we have.

    We have direct measurements of ice extent going back a century, and reconstructions going back thousands of years. As I have said repeatedly, all this data shows a relatively stable ice pack (until global warming intervened).

    The last century

    Two thousand years of polar temperatures

    900 year Arctic ice reconstruction
    Memory is an unreliable thing.

    Comment by Didactylos — 25 Jul 2011 @ 4:23 AM

  169. If you are interested in the environmental impact of slash and burn agriculture, such as global warming and deforestation, The Frontline Club is holding a screening tonight in Paddington of “Up In Smoke.”

    Filmed over a period of three years across the globe, Up in Smoke follows pioneering scientist Mike Hands as he attempts to change one of the most carbon-emitting practices in the world: slashing and burning rainforests for subsistence agriculture.

    Combining Hands’ scientific research with the lives of the impoverished farmers who depend on slash and burn agriculture for their livelihood, the film examines the real cost of carbon and the attempts to change environmentally damaging practices.

    The core of the film is Hands’ attempts to put slash and burn agricultural practices on the agenda at the 2009 Copenhagen Summit and draw global attention to the issue. Up in Smoke shows the desperate working conditions of the farmers in South America and addresses the complex moral questions about the demands of saving the planet for the future and protecting the livelihoods of people living today.

    The film is followed by a Q&A with the director, Adam Wakeling, and revolutionary ecologist Mike Hands, which should lead to a productive, informative, and essential discussion for any of those passionately interested in issues related to climate change.

    For more information, please visit: http://www.frontlineclub.com/events/2011/07/screening—up-in-smoke.html

    Comment by Frontline Club — 25 Jul 2011 @ 5:39 AM

  170. PAM, my crude understanding of what happens to an icecube is this:

    It starts off at -18°C, straight out of the freezer or icemaker. If you drop it into a cold drink, then it won’t start melting much – the drink is already close to 0°C. Over time, the icecube will melt a little at the edges, keeping your glass cold. But also, the entire icecube will gradually warm up. When it reaches close to 0°C, the rest of the cube will melt fairly quickly.

    I’m not sure quite how much of this transfers to Arctic sea ice. There are a lot of different melting processes going on.

    Comment by Didactylos — 25 Jul 2011 @ 8:05 AM

  171. Geoff Beacon:

    I’m as concerned as you about the possibility of a clathrate gun effect or rapidly melting permafrost. However, climate models can’t incorporate detailed feedbacks until they are understood reasonably well.

    Current observations show that a) clathrates are melting, and methane is bubbling already, and b) a lot of the methane is dissolving in the water, and c) it’s not yet a catastrophic event – the margin of bubbling is closely tied to ocean temperature and is moving slowly.

    So, since all this ultimately leads to more CO2 and methane in the air, any potential short term effect is very likely to already be covered by the envelope of IPCC emissions scenarios.

    Comment by Didactylos — 25 Jul 2011 @ 8:18 AM

  172. John Pollack quoted Kevin Trenberth in comment #158 above:

    “Given that global warming is unequivocal, the null hypothesis should be that all weather events are affected by global warming rather than the inane statements along the lines of ‘of course we cannot attribute any particular weather event to global warming’. That kind of comment is answering the wrong question.”

    Would all climate scientists who EVER speak to the public and/or the media about global warming please memorize that passage and repeat it at every opportunity?

    Thank you.

    We live on an anthropogenically warmed planet now. If you want to experience weather that is unaffected by anthropogenic global warming, you will have to go to another planet. Because there is no such thing any more on Earth.

    Comment by SecularAnimist — 25 Jul 2011 @ 9:33 AM

  173. WRT Didactylos’ graph at 115,

    I have been thinking for some time that I wish NSIDC or whoever uses their data (or the ice-volume data as opposed to ice extent) would limit their multi-year graphs to a two-color scheme. A graph is inherently a visual tool; limiting the graph to gradients from one color to the other allows the reader to ‘see’ the overall pattern over time much more easily. (Unless they suffer reduced color vision, of course.)

    Personally, I don’t care if it is yellow-orange or red-blue. Though, higher contrast might be desirable. Highest contrast would be between complementary colors, like green-red or blue-orange. Though, you might end up with some blah browns in the middle if you do that. On the other hand, the browns in the middle of the color change, but not in the middle of the progression of lines might be a good clue as to how the trend is accelerating. It would take some playing with to sort out the combination that pops the information in an instant.

    It might even be enough to have one or more of the color pixels (red, green, or blue) vary from between min and max illuminations based on + * ( – )/. That would change the color as well as the brightness, which would make it work in greyscale as well. Mmm, an example:

    Five years of data with only red changing, from 10% red to 90% red:
    (Hex values of RGB in the form #RRGGBB)

    #197F7F
    #4C7F7F
    #7F7F7F (mmm, that would be grey; not sure that is what we want)
    #B27F7F
    #E57F7F

    Well, I can tell you’ve given it some thought, but maybe this will give you something to try if you haven’t already.

    The only other way of avoiding the spaghetti look that I can think of offhand is to add a time axis and project the plot in 3-D.

    Comment by Chris G — 25 Jul 2011 @ 10:28 AM

  174. 167, Didactylos: 900 year Arctic ice reconstruction

    Is it known why the Arctic ice extent was greater during the Medieval Climate Optimum than it is now?

    Comment by Septic Matthew — 25 Jul 2011 @ 10:34 AM

  175. PAM,

    Mmm, I don’t know that a glass of ice is a good analogy for large ice masses, but…

    If you stick a thermometer into a completely frozen block of ice in a glass, and set it out in an above freezing environment, what you will see is this:

    There will be a relatively rapid rise, though nonlinear, up to the melting point.

    The temperature will barely move (not at all in theory) as the ice goes through a phase state change to water. There is a lot more energy in water at 0 C than there is in ice at 0 C, and the increase in energy is reflected in the lower ice volume rather than a change in temperature. (Which is why in a survival situation, you should melt snow before drinking it if at all possible.)

    Once all the ice is melted, there will again be a rapid rise in temperature.

    So, I surmise that once the summer extent drops to zero, or near enough, we will see more rapid changes in the weather patterns than we have so far.

    Comment by Chris G — 25 Jul 2011 @ 10:54 AM

  176. Bother, my pseudo-code at 171 must have gotten interpreted as HTML tags:

    min + number_of_years_since_start * (max_illumination – min_illumination)/total_number_of_years

    Comment by Chris G — 25 Jul 2011 @ 11:02 AM

  177. 170, Secular Animist, and others before: “Given that global warming is unequivocal, the null hypothesis should be that all weather events are affected by global warming rather than the inane statements along the lines of ‘of course we cannot attribute any particular weather event to global warming’. That kind of comment is answering the wrong question.”

    What is the value of the new null hypothesis (or a reasonable range)? The global temperature record shows one of the following:

    a. steady rise of temperature at a constant rate, with an independent autocorrelated residual process;

    b. alternations of warming and non-warming, with the warming epochs all displaying the same rate of warming.

    An analysis published in Nature earlier this year, and featured on Real Climate, showed an increase in rainfall maxima in a large region of the U.S. of about 7% over about 50 years, or about 0.15% per year. Would you accept or propose that as a reasonable null hypothesis for future work (or a reasonable basis for formulating a prior for future Bayesian analysis)?

    Worldwide, there is a slight increasing trend in total rainfall; would you propose or accept that trend line as a null hypothesis (or a basis for a prior)?

    Trenberth’s comment is not inherently unreasonable, as to the phenomena of climate change, but it is vague.

    Other long trends have been empirically revealed: decline in Arctic Ice, increase in Antarctic Ice, decline in total American tornado intensity, decline in global hurricane energy. Should we take the estimated trend lines for all of these measurements as null hypotheses?

    It isn’t a bad idea, but it needs explication.

    Comment by Septic Matthew — 25 Jul 2011 @ 11:08 AM

  178. Septic Matthew,
    What are you talking about?

    a) the rise is more than linear
    b) regardless of the warming rates, you are leaving off the periods of cooling, which are decreasing in rate and duration

    Them there are a lot of fancy words, but your founding premises are simply wrong.

    Comment by Chris G — 25 Jul 2011 @ 11:22 AM

  179. Septic Matthew: “Is it known why the Arctic ice extent was greater during the Medieval Climate Optimum than it is now?”

    Global warming. Duh.

    Our results suggest that as of 1985, Arctic summer sea ice cover extent dropped below the lower bound of the reconstructed minimum for the Medieval Warm Optimum (ca AD 1150). These findings support the contention that human influence on Arctic sea ice became detectable after the early 1990s.

    Comment by Didactylos — 25 Jul 2011 @ 11:39 AM

  180. Didactylos @169

    The clathrate gun may be another missing feedback but as you say, “climate models can’t incorporate detailed feedbacks until they are understood reasonably well” – but more prominence should be given to what is omitted.

    However, my main comment was not on missing methane feedbacks but the carbon dioxide that is being released by melting tundra as discussed by Schaefer et. al.

    I think that is a feedback that is much better understood. Do look at the Open Letter to Chris Hunhe mentioned earlier for Kevin Schaefer’s comments.

    Comment by Geoff Beacon — 25 Jul 2011 @ 11:55 AM

  181. “all weather events are affected by global warming”

    Yeah personally, I’d rather prefer to have it proven to me unequivocally how a given weather event can’t be affected by AGW.

    Scientists have to be careful about how they advocate or engage politically, but that shouldn’t stop them from complaining strongly about dilly-dallying, or even what amounts to criminal neglect of the problem.

    Edward Greisch @ 151

    “Most people have to have a solution to the problem before they will admit that there is a problem.”

    Reminds me of the Old English poem “The Wanderer” (there are lots of better translations on the net than I can devise):

    64-77
    Forþon ne mæg weorþan wis wer, ær he age
    wintra dæl in woruldrice. Wita sceal geþyldig,
    ne sceal no to hatheort ne to hrædwyrde,
    ne to wac wiga ne to wanhydig,
    ne to forht ne to fægen, ne to feohgifre
    ne næfre gielpes to georn, ær he geare cunne.
    Beorn sceal gebidan, þonne he beot spriceð,
    oþþæt collenferð cunne gearwe
    hwider hreþra gehygd hweorfan wille.
    Ongietan sceal gleaw hæle hu gæstlic bið,
    þonne ealre þisse worulde wela weste stondeð,
    swa nu missenlice geond þisne middangeard
    winde biwaune weallas stondaþ,
    hrime bihrorene, hryðge þa ederas.

    112b-114a
    ne sceal næfre his torn to rycene
    beorn of his breostum acyþan, nemþe he ær þa bote cunne,
    eorl mid elne gefremman.

    Comment by Radge Havers — 25 Jul 2011 @ 12:02 PM

  182. Chris G: Complementary colours actually often result in lower contrast, because even if the hue separation is greater, the separation in brightness can be far, far lower.

    I try not to over-think things in terms of making allowances for various forms of colour-blindness, but I try to make sure there is always reasonable brightness contrast so that the hues don’t matter.

    I tried the 3D thing a while back, and was disappointed. It’s hard to communicate relative height in 3D, and the trend is subtle enough that the whole thing was just a mess. Maybe I just didn’t find the best way to present it.

    I’m happy to share my code if anyone wants to try their favourite colours.

    Comment by Didactylos — 25 Jul 2011 @ 12:07 PM

  183. Didactylos, Septic,
    I was going to say that might be an indication that either, or both, the MWP was not as warm as it is now, or it was not global in nature.

    You shouldn’t put too much weight into any one study. You kind of have to survey the field and proceed as though the truth were somewhere within the majority that are consistent with each other. The finding that ice extent was higher during the WMP is consistent with the majority of findings that it was neither as warm globally nor at the same time in different parts of the world, as it is today. It is inconsistent with the minority which hold that it was global and warmer. There is some danger of confirmation bias in this method, but as long as you are willing to re-assess your viewpoint in light of new information, that danger is minimal.

    So, you should take the paper’s finding that sea ice extent was greater during the MWP to be in support of that period not being warmer than today rather than take it to mean that there must be something wrong with the paper because it is inconsistent with the minority position that the period was global and warmer.

    Minorities are sometimes correct, but it isn’t the way to bet.

    Comment by Chris G — 25 Jul 2011 @ 12:31 PM

  184. Didactylos @ 180

    The image isn’t coming up for me, but FWIW and if it’s really an issue, a starving artist might be able to subtly and effectively tweak additional visual variables in combination for you (hue, saturation, value, line weight, line texture, and perhaps transparency) using other software, and do it in ways that aren’t obstructive to meaning — within limits of course.

    Comment by Radge Havers — 25 Jul 2011 @ 12:44 PM

  185. Chris G, the study doesn’t say that “ice extent was higher during the WMP” – it says the opposite.

    Is there some other study that says otherwise?

    Comment by Didactylos — 25 Jul 2011 @ 12:50 PM

  186. Didactylos,
    All true.

    What about a dark, say red, to a bright yellow? Color-wise, that would be stepping red down while stepping blue and green up, something like

    #0A0000

    #00FFFF

    Just thinking. I wonder if a human factors expert could offer some suggestions. Or, better, if some climate researcher at a university could get together with some human factors person in the cognitive psych department. If they come up with something good, then others will emulate. That would be a neat ‘trick’.

    I found this, which looks like some good starter material, but limited.

    http://www.visualexpert.com/FAQ/Part5/cfaqPart5.html#p5.11

    Comment by Chris G — 25 Jul 2011 @ 12:51 PM

  187. Quite a clear view of the ice on the Siberian side of things today. Nick Barnes, if you’re reading: the holes you were looking for are starting to show up.

    The (multiyear) ice in the Beaufort is taking a beating, the ice in the East Siberian Sea is brown and grey, the ice in the Laptev Sea is being torn apart by that low-pressure system, the ice in the Northwest Passage AND the channels in the Canadian Archipelago is disintegrating (multiyear ice from the Arctic Basin is going to board the train soon), while ice in the Greenland Sea is slowly being pushed towards Fram and Olga Strait (and then lower latitudes).

    Man, this is exciting! What a melting season!

    Comment by Neven — 25 Jul 2011 @ 1:35 PM

  188. Didactylos #183,
    I missed a ‘not’, as in, ‘_not_ greater’, at comment #181.

    It’s only an apparent disagreement, not a real one.

    Comment by Chris G — 25 Jul 2011 @ 1:49 PM

  189. OK, I’m over-thinking the graph problem, but here goes…

    The physical material that is being represented is ice and water. That naturally lends itself to using a white-blue color scheme, but white would only work on a black background. Plus, different colors represent different years, not varying amount of ice versus water. While using this combination would amplify the perception of the existing trend, it could be construed to be a ‘trick’ of the deceptive kind rather than a ‘trick’ of the clever kind. Plus, a darker blue will perceptually appear to be ‘further away’ than a lighter blue; so, if one uses lighter colors when there is more ice, there will be a dissonance between perceived distance in space and actual distance in time. Further away in time will appear closer in space.

    Any major hue change crosses a grey area. This could be good or bad. It would convey a midpoint in time, but could also convey a meaning of a neutral time, which might be confused with a baseline average, which it would not be.

    The fact that light colors tend to appear closer than dark colors could still be used to as a time analogy. But, the darker colors should represent years farthest back in time.

    We are still talking about ice and water; so, personally, I’d go with blues and/or greens.

    OK, my two cents, if it were me, I’d go with something like a navy blue transitioning to a cyan:

    #000080

    #00FFFF

    http://www.tayloredmktg.com/rgb/

    (Yeah, I goofed; 00ffff (above) is cyan; yellow is ffff00.)

    Comment by Chris G — 25 Jul 2011 @ 3:03 PM

  190. ach, #186, errata,

    “Our results suggest that as of 1985, Arctic summer sea ice cover extent dropped below the lower bound of the reconstructed minimum for the Medieval Warm Optimum (ca AD 1150). ”

    If it is now below the lower bound minimum of the reconstruction, then it was greater during the MWO reconstruction than it is now. I think one of us is misreading the other.

    Comment by Chris G — 25 Jul 2011 @ 3:14 PM

  191. I have updated the East Siberian Sea animation. Finally a relatively clear picture. The difference is absolutely stunning.

    Comment by Neven — 25 Jul 2011 @ 3:53 PM

  192. 181, Chris G.: So, you should take the paper’s finding that sea ice extent was greater during the MWP to be in support of that period not being warmer than today rather than take it to mean that there must be something wrong with the paper because it is inconsistent with the minority position that the period was global and warmer.

    Isn’t it accepted that the MWP applied to the Northern Hemisphere generally? The reconstructions mostly put the MWP warmer than now, but they are merely reconstructions, and as you say, they may be in error.

    Comment by Septic Matthew — 25 Jul 2011 @ 3:55 PM

  193. OK, still over-thinking…

    Probably been thought of before, but aggregating over 4-6 years might smooth out the inter-annual variability enough to make the trend easier to see, both for a color graph and a 3-D graph. That would obviously loose some detail, but I’ve learned that messages, especially to pointy-hair boss types, are more persuasive when they are less obscured by details; so, it depends on the target audience.

    Comment by Chris G — 25 Jul 2011 @ 3:56 PM

  194. Santa.

    If we reach another ice minimum this year, or whenever, and the ice-free North Pole is real, even if only for a short time in summer, Santa will be the new ambassador of Climate Change. He’ll start as a summer joke meme – where does his house go? Are the elves Mer-men? – but he’ll be remembered a few months later at the holidays. And the culture will shift…

    Comment by Ethan Sprang — 25 Jul 2011 @ 4:25 PM

  195. I have made an animation of the Canadian Archipelago.

    Quote from the post:
    “Up till now that multiyear ice that was pressed against the Canadian Archipelago had something to press up to. But as we saw in the first half of August last year all of the ice in those channels started breaking up and multiyear ice was transported from the Arctic Basin to lower latitudes where a lot of it melted out. Some of it froze up in the Northwest Passage, which could be a reason the passage is a bit slower in breaking up than it was last year.”

    Needless to say, this is a very important area to keep an eye on.

    Comment by Neven — 25 Jul 2011 @ 4:49 PM

  196. > Isn’t it accepted that the MWP applied to the Northern Hemisphere generally?

    Why would you think that?

    http://www.google.com/search?q=site%3Aipcc.ch+medieval+warm

    Comment by Hank Roberts — 25 Jul 2011 @ 4:59 PM

  197. Just reading this thread shows the difficulty inherent in trying to disseminate accurate scientific findings. Titus, in #161 says:

    I grew up in the 50′s and 60′s and remember that Arctic extent increased quite significantly around the middle of that century

    Didactylos in #170 ‘corrects’ Titus:

    … your memory is not reflected by the long-term records we have.

    And Didactylos even provides a link to a graph of the previous century’s Sea Ice Extent. But the graph DOES show a peak in sea ice extent in 1953. So Titus’ memory isn’t all that bad. Of course the peak in extent correlates to a regional and global drop in temperature. That SIE increased briefly is hardly a surprise.

    While it did increase in the early 1950′s, I’m not sure we could categorize it as ‘significantly’ – the data has plenty of uncertainties given the reanalysis methods. On the other hand, many skeptic sites have photos of submarines surfacing at the North Pole in the 1950s … to their minds ‘proving’ there was LESS ice in the Arctic as recently as the late 1950s. There is NO support for that view.

    Titus goes on to say:

    We were also taught that wind and currents had a significant effect. I guess when my generation leaves you will have an easier time getting folks to adopt the current thinking.

    I’m a bit skeptical here myself. I’m only a few years younger than Titus and the only time I even remember the Arctic being mentioned is when the Manhattan sailed across it. Unless you were an oceanographer specializing in the Arctic Ocean it was not a topic of conversation. The gratuitous jab at ‘kids these days’ is misplaced. We know far more about the effects of wind, currents, and a whole host of other weather and climate-related variables and how they effect sea ice transport, extent, area and volume than at any time in human history. Climate scientists today not only consider all these variables (including wind and currents) they are able to quantify them. To believe that somehow more was known about the Arctic 60 years ago is nonsense.

    Comment by Kevin O'Neill — 25 Jul 2011 @ 5:03 PM

  198. Northern Hemisphere only – I don’t have a firm belief one way or the other. My understanding is that evidence in the south is harder to find than evidence in the north.

    Broeker says global – http://www.sciencemag.org/content/291/5508/1497.short

    Villalba says also in SH, but the timing is odd; there is a cool spell there when there is a warm spell in the NH, according to some others – http://www.springerlink.com/content/x0214563n1n44731/

    Mann (2008) seems to find something happening in the SH, but not clear to me that it coincides with what was happening in the NH –
    http://www.pnas.org/content/suppl/2008/09/02/0805721105.DCSupplemental/0805721105SI.pdf

    Timing and location – If memory serves, timing of the peak is an issue; from as early as ~850 AD to as late as ~1150 AD. That’s quite a bit of variance for a period only 3-4 hundred years long to begin with. It’s there in most records, just not everywhere at the same time. I have no real idea why that would be; maybe shifts in ocean currents? A little more heat here, a little less there. Currents can do that.

    Generally warmer than today – not according to the majority of papers I’ve had a chance to look at. Then there are also the sea ice reconstructions which show extents lower in recent decades and the algae that disappeared from the Atlantic 800,000 years ago and have only recently been found again in the North Atlantic. Best guess is they came across the Arctic ocean from the Pacific.

    Here is, not an actual paper, but a summary of several:
    http://skepticalscience.com/print.php?n=394

    Comment by Chris G — 25 Jul 2011 @ 5:22 PM

  199. Santa will be the new ambassador of Climate Change.

    Santa. Right. Sure. You could try reality. It works for me.

    Comment by Thomas Lee Elifritz — 25 Jul 2011 @ 5:37 PM

  200. Chris G at # 173:

    There is a lot more energy in water at 0 C than there is in ice at 0 C, and the increase in energy is reflected in the lower ice volume rather than a change in temperature.

    Lower ice volume? This seems to contradict that water is denser then ice.

    Comment by Chris O'Neill — 25 Jul 2011 @ 6:31 PM

  201. The globalization of the MWP was being discussed on another bog, and I ran across this: Medieval Climate Anomaly. Some might find it interesting.

    Comment by JCH — 25 Jul 2011 @ 6:53 PM

  202. >> Chris G at 173 … lower ice volume …
    >Chris O at 198 .. water is denser …

    Ice melts to water (the volume of ice decreases the volume of water increases); absorbing energy, while the temp. stays around 0 C

    Comment by Hank Roberts — 25 Jul 2011 @ 8:08 PM

  203. I have updated the East Siberian Sea animation. Finally a relatively clear picture. The difference is absolutely stunning.

    Comment by Neven — 25 Jul 2011 @ 3:53 PM

    A more complete treatment of the Northwest and Northeast Passages is here:
    http://aperfectstormcometh.blogspot.com/2011/07/current-state-of-arctic-sea-ice-laymans_21.html

    Original post here: http://aperfectstormcometh.blogspot.com/2011/07/current-state-of-arctic-sea-ice-laymans.html

    Comment by ccpo — 25 Jul 2011 @ 8:54 PM

  204. I’ve added annotations to the latest image of ice in the East Siberian Sea and found a depth chart for the ESS and linked it.

    http://aperfectstormcometh.blogspot.com/2011/07/current-state-of-arctic-sea-ice-laymans_21.html

    Looks like the open water route is only between 1 and 3 fathoms, probably unrealistic for seagoing vessels, no? If so, they’ll have to go through the pretty loose-looking sea ice fields. Looks very doable, particularly with ice breakers on standby or along for the trip, as seems to be the case in the last couple of years.

    That ice is amazingly resilient, not having changed much for a number of days. Six more days to August. I think it will be unambiguously open by then…. maybe.

    This is not a prediction!

    ;-)

    Comment by ccpo — 25 Jul 2011 @ 10:03 PM

  205. 167 Didactylos:
    “The most striking feature of our pan-Arctic sea-ice cover reconstruction is the abrupt and sustained decrease in summer ice extent observed during the second half of the 20th century, which is apparently unprecedented in the previous ~9 centuries. Our results suggest that as of 1985, Arctic summer sea ice cover extent dropped below the lower bound of the reconstructed minimum for the Medieval Warm Optimum (ca AD 1150). These findings support the contention that human influence on Arctic sea ice became detectable after the early 1990s. ”

    + another hockey stick.

    “unprecedented in the previous ~9 centuries” says it all.
    “detectable” is so far understated that it just isn’t reasonable. Here is where the correct word is “obvious” and scientists should use it. If it said “The crossover point to warmer for sure than the MWP happened in 1990″ that would make sense.

    179 Radge Havers: Sorry, I don’t see the connection to any translation of “The Wanderer”. I was talking about a defect in the design of the human brain that must be overcome.

    Comment by Edward Greisch — 25 Jul 2011 @ 10:58 PM

  206. Updated the Fram Strait images to include 22nd – 25th. I can’t make a slide show on Blogger, but I can link to one. If anyone can suggest a good site to host a slideshow I can link to, let me know, please.

    Comment by ccpo — 26 Jul 2011 @ 12:17 AM

  207. Correction:

    OK, modelling is hard, we cannot expect perfection but we must publicise their defects.

    Comment by Geoff Beacon — 26 Jul 2011 @ 2:26 AM

  208. 194, Why would you think that?

    Annals of Applied Statistics, vol5, no. 1, March 2011, pp 5 – 124.

    Comment by Septic Matthew — 26 Jul 2011 @ 2:33 AM

  209. ccpo,

    Please email me at levenson1960@gmail.com

    Comment by Barton Paul Levenson — 26 Jul 2011 @ 3:31 AM

  210. Kevin O’Neill:

    I don’t want to be overly pedantic, but the minor peak in ice extent you are talking about saw an increase during the 40s, and decreased sharply in 1953. It is also only really notable in the summer extent – it doesn’t exist in the annual data. And, as you observe, it isn’t “significant” in any sense, especially given the caution in the documentation for the data:

    Please note that much of the pre-1953 data is either climatology or interpolated data and the user is cautioned to use this data with care.

    This makes the discontinuity at 1953 all the more suspect. My point that there was no significant change to ice extent in this period stands.

    Looking at a regional breakdown, it seems that most of the “increase” is likely to be observed in Hudson Bay, so maybe Titus does remember some regional news story.

    Comment by Didactylos — 26 Jul 2011 @ 6:27 AM

  211. I notice that the Antarctic Ice extent has been trending upwards for the past 30 years and this trend is still continuing
    ref: http://nsidc.org/data/seaice_index/images/s_plot_hires.png

    My question is – How much does this offset the Arctic increase in terms of albedo? Also, since this ice extends further towards the equator then would it also provide more reflection per sq. km ?

    How long do you expect the Antarctic ice trend to continue along with the continued cooling trend in the Southern Ocean ?

    Comment by Jonas — 26 Jul 2011 @ 7:41 AM

  212. My previous comment appears to have been lost so I’ll try again. This will be the third attempt. It was an addition to my comment at #161 and several folks have commented so I’m giving the curtosy of a reply.

    To check my memory I consulted one of my old encyclopedias (Book of Knowledge by Waverley 1950’s edition). It talked about Russia building out towns on the north coast of Siberia and setting up a sea trade along the route for the ice free months. It also talked of growing flax and sugar beet inside the Arctic Circle.
    Then I remember the ice came back in the 50’s and 60’s (maybe some of 70’s) and put a stop to this expansion. Similar type stories for the Baltic Sea.
    Your data does not seem to identify this very well.
    So my memory was not too far out. Our current extents seem pretty similar to what they were back in the 1940’s and 50’s having receded since about the 80’s. Looks more of a cyclical process to me.

    Comment by Titus — 26 Jul 2011 @ 10:19 AM

  213. Titus: rather than trying to piece together a viewpoint from old encyclopedia articles, you can look at compiled data from old sea ice charts:

    http://nsidc.org/icelights/2011/01/31/arctic-sea-ice-before-satellites/

    Whatever local conditions existed in whatever Siberian towns you have read about, for arctic sea ice as a whole, extents are not remotely similar now to what they were in the 1950s.

    Comment by Kevin Stanley — 26 Jul 2011 @ 10:44 AM

  214. Titus, you can do better than an old 1950s encyclopedia for the facts.

    Long day length during the summer allows both farming and travel and has for a long time — for annual plants and small shallow draft vessels.
    http://www.google.com/search?q=flax+“sugar+beet”+”arctic+circle”+siberia

    You’re going beyond the facts to claim a cycle — that’s not in the facts:
    http://www.agu.org/pubs/crossref/2011/2010JD015341.shtml

    Look at what’s actually happening. Cite sources from the science.
    You can do this. Make the effort. Look for the facts first, don’t decide what you believe then go looking for support. That kind of ‘reverse citation’ fails because you can find anything you want, if you look only for what you want.

    http://www.biogeosciences-discuss.net/8/1445/2011/bgd-8-1445-2011-print.pdf

    Comment by Hank Roberts — 26 Jul 2011 @ 10:45 AM

  215. SM’s pointing to this journal for his “isn’t it generally accepted” question assuming the ‘Medieval warm period’ was a Northern Hemisphere pattern:

    http://projecteuclid.org/DPubS?service=UI&version=1.0&verb=Display&page=toc&handle=euclid.aoas/1300715166
    The main article in that is: “A statistical analysis of multiple temperature proxies: Are reconstructions of surface temperatures over the last 1000 years reliable?” – Blakeley B. McShane and Abraham J. Wyner; 5-44

    Those who’ve been reading a while will understand the problem. If you’re new to the subject, here’s a place to start.

    http://www.google.com/search?q=site%3Arealclimate.org+mcshane+wyner

    Shorter: Nope, it’s not generally accepted.

    If it were in the IPCC Report, it would be, but as it isn’t, it ain’t.

    Comment by Hank Roberts — 26 Jul 2011 @ 10:58 AM

  216. SM wrote:
    > Isn’t it accepted that the MWP applied to the Northern Hemisphere generally?

    I pointed out that it isn’t:
    http://www.google.com/search?q=site%3Aipcc.ch+medieval+warm

    SM wrote:
    > Annals of Applied Statistics, vol5, no. 1, March 2011, pp 5 – 124.

    The paper SM’s citing:

    http://projecteuclid.org/DPubS?service=UI&version=1.0&verb=Display&page=toc&handle=euclid.aoas/1300715166

    is McShane and Wyner, claiming it’s “generally accepted”

    Check that out:
    http://www.google.com/search?q=site%3Arealclimate.org+mcshane+wyner

    Comment by Hank Roberts — 26 Jul 2011 @ 11:07 AM

  217. Further on McShane and Wyner for SM:
    http://www.google.com/search?q=site%3Atamino.wordpress.com+mcshane+wyner

    So, SM, your reason for asking “isn’t it accepted” — was that it?
    That one problematic paper?

    There’s a reason for the slow grinding process by which the IPCC puts together what’s generally accepted every five years or so. You can’t pick one contentious paper out and claim general acceptance for a quirky notion.

    Or can you?

    Comment by Hank Roberts — 26 Jul 2011 @ 11:15 AM

  218. Oh, dear, SM, I’d forgotten most of that.

    McShane and Wyner was the hot item at the denial sites, a while back, and thoroughly dissected. Here’s another take:

    http://shewonk.wordpress.com/2010/08/15/the-eternal-return/

    > isn’t it accepted …?

    Nope. Except perhaps by those who believe climate is just repeating cycles.

    Comment by Hank Roberts — 26 Jul 2011 @ 11:38 AM

  219. Edward Greisch @ 203

    I know. In the context of the general thread on how scientists should communicate, your comment sparked a synapse. The association is loose, but the summary of attitudes and expectations seemed evocative to me:

    Edward Greisch @ 151

    “Most people have to have a solution to the problem before they will admit that there is a problem.”

    The Wander (here goes, more or less):

    “…a warrior shall never express too quickly the grief from his heart, unless he already knows the remedy, an earl accomplished in every respect…”

    Also:

    “…Therefore a man     cannot call himself wise, before he has
    a share of years in the world.     A wise man must be patient,
    He must never be too hot-hearted     nor too hasty of speech,
    nor too weak a warrior     nor too reckless,
    nor too fearful, nor too cheerful,     nor too greedy for riches,
    nor ever too eager for boasting,     before he can have clear understanding.
    A warrior shall wait     when he speaks oaths,
    until stout-hearted     he sees clearly
    whither the intent of his heart     will turn.
    A wise hero can perceive     how ghastly it will be,
    when all this world’s wealth     stands waste,
    as now in various places     throughout this middle-earth
    walls stand,     blown by the wind,
    covered with frost,     the buildings storm-swept….”

    Comment by Radge Havers — 26 Jul 2011 @ 11:47 AM

  220. Sorry ’bout multiple posts. ReCaptcha said each had failed, so I rewrote and retried several times — and now I see all of the ‘rejected’ tries showed up.

    Comment by Hank Roberts — 26 Jul 2011 @ 12:34 PM

  221. Titus: I would strongly question any information from that period. The cold war was fought mainly with misinformation – unpicking the reality is not simple.

    The truth is that differences in various reconstructions show that the margin of error is far greater than any perceived “peak”. The fact that you can’t pin this peak down to even a specific decade should be a clue to this.

    You’re chasing data ghosts and memories.

    We can be very certain that the current ice loss is not comparable to anything in the last century, and probably not comparable to anything in the last millennium.

    Comment by Didactylos — 26 Jul 2011 @ 1:04 PM

  222. Titus said: “Our current extents seem pretty similar to what they were back in the 1940’s and 50’s having receded since about the 80’s. Looks more of a cyclical process to me.”

    I think this claim needs addressing directly, since it is flat out false. Titus, where are you getting this crazy idea from? You must have SOME source for this idea, since you keep repeating it.

    We have supplied at least three reputable sources that flatly contradict the claim.

    Comment by Didactylos — 26 Jul 2011 @ 1:15 PM

  223. Jonas:

    My understanding is this – ice albedo has the greatest effect during the polar summer. This coincides with the period of melt and sea ice minimum.

    Because Antarctic sea ice reduces to almost nothing in the summer/autumn, there is very little trend in the ice minimum, and consequently any albedo effect is greatly constrained.

    In the Arctic, the minimum is not constrained in any way, since there isn’t a continent in the way. This means that albedo already plays a significant role in the Arctic.

    This isn’t the end of the story, though, because additional sea ice in the Antarctic winter does have consequences. I just don’t know what those consequences are.

    Comment by Didactylos — 26 Jul 2011 @ 1:26 PM

  224. Jonas (211):

    The increase in Antarctic sea ice extent has mainly been occurring in the winter (see the graph of the past few years on Cryosphere Today), when albedo is insignificant. Also, the Southern Ocean has been warming (in fact, warming faster than the global trend), not cooling, as Skeptical Science explains:

    http://www.skepticalscience.com/antarctica-gaining-ice-intermediate.htm

    Overall, global sea ice is decreasing:

    http://tamino.wordpress.com/2011/01/14/monckton-skewers-truth/

    [Response: These are nice links, but as usual they ignore the fact that Antarctica sea ice increase is limited to East Antarctica, whereas West Antarctic and Peninsula sea ice is in fact decreasing, and has been for the last 30+ years, at least. The fractional increase in East Antarctica is much smaller than the decrease in West Antarctica. Like for the (glacier, as opposed to sea ice) ice sheet itself, the largest changes are occurring in West Antarctica.--eric]

    Comment by Michael Stefan — 26 Jul 2011 @ 1:55 PM

  225. 220, Hank Roberts: Sorry ’bout multiple posts. ReCaptcha said each had failed, so I rewrote and retried several times — and now I see all of the ‘rejected’ tries showed up.

    That has happened to me too.

    Comment by Septic Matthew — 26 Jul 2011 @ 2:00 PM

  226. 218, Hank Roberts: McShane and Wyner was the hot item at the denial sites, a while back, and thoroughly dissected. Here’s another take:

    I referred to the McShane and Wyner paper, the critiques, and the rebuttal. I also have downloaded the supporting online material.

    Comment by Septic Matthew — 26 Jul 2011 @ 2:05 PM

  227. Hank Roberts, Are you saying that the Medieval Warm Period is accepted to have been merely European, and not even general over the NH?

    Comment by Septic Matthew — 26 Jul 2011 @ 2:11 PM

  228. Re Titus (the dubious),

    It is true that in the 1950s Siberia experienced a phase of development as part of one of the long term plans of the Communist government. This involved the construction of hydro-electric plants and following aluminium smelting industry. Furthermore the discovery of gas and oil fields.

    Titus has no evidence for his/her claim of increased sea-ice and the equally baseless insinuation of a climatic cycle.

    The evidence that there is shows that Titus is incorrect.

    e.g. Arctic Sea Ice Extent and Anomalies, 1853 to 1984. Mysak & Manak, CRG Report No 88-8, June 1988.

    The following 2 figures show monthly sea-ice anomalies for the period 1953 to 1985.

    Figure 20, Barents & Kara Seas, shows no significant anomaly from 1953 to 1965. Then a peak around 1970 before a resumption of the no significant anomaly until the end of the series, 1985, where there is a steep drop from 1982.

    Figure 21, Siberian & Laptev Seas, shows no significant anomaly for East for the full period 1953 to 1985.

    Comment by Chris R — 26 Jul 2011 @ 2:32 PM

  229. Thanks for publishing my comment. I’m having great difficulty and this will be the second attempt at this one.

    Had some time so did a Google search to complement my 1950′s encyclopedia. Came across this one which looks good to share.

    http://seaice.alaska.edu/gi/publications/mahoney/Mahoney_2008_JGR_20thC_RSI.pdf

    At the very least it shows that Arctic ice decreased up until 1953 and then increased. We can discuss the merits and usefulness. However, it does back up to some extent my memory and 1950′s encyclopedia:)

    Comment by Titus — 26 Jul 2011 @ 3:09 PM

  230. Titus, your link has usefulness, such as this:”Periods A and B are not evident in the HadISST data,
    which show a more continual decline in summertime
    Russian sea ice during the twentieth century. Although we
    have reason to question the quality of the early AARI data
    in autumn months, the good correlation with passive microwave
    results gives us confidence in the summertime
    AARI ice extents. The HadISST data therefore miss a
    potentially important transition that occurred in the 1980s,
    when the Arctic sea ice retreat became a basin-wide and
    year-round phenomenon.”

    In other words, rather than a slow decline over decades, the patient is suddenly getting worse.

    Comment by t_p_hamilton — 26 Jul 2011 @ 4:07 PM

  231. Titus,

    From the paper you cite, and supported by the graphs (fig 6 & 7).
    “Up until the 1950s–1960s and after the 1980s, summertime sea ice extent was decreasing around the Russian Arctic. During the intervening period, the retreat of sea ice slowed or reversed.”

    Summer is most relevant to your claim that shipping was stopped by an increase in ice in the 1950s. At best the increase from the mid 1950s was partial and patchy in nature (figure 6), it did not return to levels of the 1940s. That paper does not support your claim of an increasing sea-ice in the 1950s that stopped shipping as the the 1950s was a lull not a peak nor the start of a peak.

    You can see from the study the context of current conditions. This is not a cyclic situation. The current recession is due to warming driven largely by human activities mainly CO2 emissions.
    “Period C began in the mid-1980s and continued to the end
    of the record. It is characterized by a decrease in total and
    MY sea ice extent in all seas and seasons. In this regard,
    period C is markedly different from periods A and B.”

    Comment by Chris R — 26 Jul 2011 @ 4:17 PM

  232. > mahoney
    previously cited here http://www.google.com/search?q=site%3Arealclimate.org+mahoney+jgr
    to make the same argument you’re making, by Max at
    http://www.realclimate.org/?comments_popup=606#comment-132431

    Always look the paper up, so you can check more recent citing papers:
    http://scholar.google.com/scholar?cites=10638625586393882405&as_sdt=2005&sciodt=0,5&hl=en

    Don’t stop looking when you find something that supports what you _want_ to believe.

    Comment by Hank Roberts — 26 Jul 2011 @ 4:25 PM

  233. PS, this in particular is interesting:

    http://www.clim-past-discuss.net/4/S600/2008/cpd-4-S600-2008-print.pdf
    CPD
    Interactive Discussion
    Clim. Past Discuss., 4, S600–S605, 2008
    http://www.clim-past-discuss.net/4/S600/2008/

    Interactive comment on “Can we reconstruct
    Arctic sea ice back to 1900 with a hybrid
    approach?” by S. Brönnimann et al.

    Short answer: the attempt was not successful — not yet

    Brief quote:

    “… During the work on these reconstructions, several new data sets were published, including new historical data products (e.g., Mahoney et al. 2008) as well as new reconstructions (e.g., Kauker et al., 2008). At the same time, new climate model versions are being developed in the process of preparations for the IPCC Fifth Assessment Report, and a new version of HadISST is currently being developed. We are confident that in only 4-5 years from now, such an approach can in fact be successful. Progress is much faster than we anticipated, which however raises the question of the value of publishing a “no result” in the peer-reviewed literature at this time.
    In view of these thoughts, we have therefore decided not to take this manuscript further, but rather to undertake a new attempt in a few years.”
    _________

    That’s an example of why you find new information by looking at the citing papers, Titus, rather than just looking for something that supports what you want to believe and stopping with that older information.

    There’s much more there to read. I hope you do read some of it.

    Comment by Hank Roberts — 26 Jul 2011 @ 4:31 PM

  234. > SM
    > Hank Roberts, Are you saying that the Medieval Warm Period is …

    You don’t care what I think about that. Neither do I.
    Look this stuff up.

    Your source is McShane and Wyner. Did you read the paper and its critics?
    http://scholar.google.com/scholar?cites=6168230330211941140

    So the paper hasn’t been cited by subsequent papers except for criticism.

    Then, look at who likes it and who doesn’t.
    http://www.google.com/search?q=mcshane+wyner

    See a pattern in that result?

    Pick someone who is not a strong advocate, with science chops, like:
    http://klimazwiebel.blogspot.com/2010/08/mcshane-and-wyner-on-climate.html

    (For this example, read at least the original post and his followup: http://klimazwiebel.blogspot.com/2010/08/mcshane-and-wyner-on-climate.html?showComment=1285257409464#c3504664301479074586

    (If you read the other comments don’t be drinking coffee over a keyboard.)

    So, SM, when you write
    > Are you saying that the Medieval Warm Period is accepted to
    > have been merely European, and not even general over the NH?

    Nope.

    Comment by Hank Roberts — 26 Jul 2011 @ 7:02 PM

  235. http://aperfectstormcometh.blogspot.com/2011/07/tracking-arctic-sea-ice-loss-via-fram.html

    Tuesday, July 26, 2011
    Large Ice Shelf Breaks Free Off Eastern Greenland

    Huge chunk of the ice shelf breaks off in the area of Bjornegletscher in the Fram Strait area of the Greenland Sea we’ve been watching to assess sea ice transport out of the Arctic Ocean.

    The total area including the piece that had already broken maybe… 8,000 sq miles, very roughly estimated. I don’t yet know if that is a permanent or seasonal ice shelf, so I will update when I know if this is a Big Deal or not.

    Comment by ccpo — 26 Jul 2011 @ 7:51 PM

  236. 234, Hank roberts: Your source is McShane and Wyner. Did you read the paper and its critics?

    yes. That was why I referred to pp 5-124, and the supporting online material. Their online rebuttal has more detail than their printed rebuttal.

    You don’t care what I think about that.

    I care what you “say” (paraphrasing my question), in this case meaning “type”.

    Comment by Septic Matthew — 26 Jul 2011 @ 8:45 PM

  237. The Northeast Passage unambiguously open as of 7/27/11.

    http://aperfectstormcometh.blogspot.com/2011/07/current-state-of-arctic-sea-ice.html

    Comment by ccpo — 27 Jul 2011 @ 12:52 AM

  238. Having trouble posting… the correction above refers to this:

    I can’t decide if this amuses or terrifies me:
    Climate change forecasters are wrong on CO2, new report claims

    And it says that while their research results add further evidence of global warming from a forecasting perspective, there is only limited evidence of a link between annual emissions of CO2 and the 10- and 20-year rise in global annual average temperatures

    Claims from competing interest groups have led to a decline in confidence in statements on climate change – particularly in the wake of allegations of manipulated data from the University of East Anglia, and incorrect projections on Himalayan glaciers.

    The Lancaster research aimed to make 10 and 20 year ahead climate predictions more accurate and trustworthy for policy-makers, and be the basis for more informed debate over the realities of climate change.

    Are we to have a balance between the Lancaster University Management School, a triple-accredited, world-ranked management school, and the claims of the IPCC?

    The IPCC use inadequate models, which obviously understate the dangers then there is a scaling down of the dangers by papers like that from LUMS.

    OK, modelling is hard, we cannot expect perfection but should we not publicise their defects.
    Who remembers the well-modelled box girder bridge collapses?

    [Response: The actual paper this referring to isn't as bad as this press report makes it appear. The authors made much more of an effort than previous 'forecasting experts' to actually learn something about what climate models are doing. However the broad statements in this piece are not supported by their study. I may do a post on this if I can find the time. - gavin]

    Comment by Geoff Beacon — 27 Jul 2011 @ 8:21 AM

  239. RE 235

    ccpo, please keep us informed regarding the movement of that massive new ice flow in the Fram Strait. Though the resolution was not adequate to tell for certain, it appeared to pop off on one day or less.

    Visited your web page. Nice piece of work!!

    Comment by John McCormick — 27 Jul 2011 @ 10:13 AM

  240. So you have 30 year log of sea ice extent. Do you expect a random variable it not to exceed its previous limits from time to time (and 4 years over 30 year long period seems to be pretty reasonable interval)? If you ask why the upper limit is not shattered, then just look over to southern hemishphere.

    [Response: The noise in the arctic sea ice cover is much smaller than the signal of the trend in every month and almost every region. This is not noise. - gavin]

    Comment by Tegiri Nenashi — 27 Jul 2011 @ 10:38 AM

  241. Tegiri:

    per NSIDC, there are more or less complete records for extent going back ~60 years, enough records to get a pretty good sense of it going back a few hundred (as long as people who keep records have been sailing in the arctic), and enough proxy data to know that the current situation is probably unique for at least the last 5000 years and quite possibly for the last 100,000+ years.

    But even considering only the last 60 years of good coverage, that’s plenty to get a sense of what the range is for annual fluctuations in the first half of that record, making it blindingly obvious that a big change is afoot in the second half of the record, especially at the end.

    Comment by Kevin Stanley — 27 Jul 2011 @ 12:39 PM

  242. Hank #232,

    I don’t see criticism of the Mahoney paper in the links you posted, the link to Brönnimann et al seemed to be a self-critique of their method. Brönnimann et al examine combining climate models and data, i.e. a reanalysis type product. The Mahoney paper is based upon Russian Arctic and Antarctic Research Institue data, observations of the sea ice edge and conditions, so the criticisms of Brönnimann et al are not relevant.

    To my shame I find I’ve had the Mahoney paper for over a year in my bulging ‘to be read’ folder. Which is why it seemed familiar when Titus linked to it. I’ve given it a quick once-over and remain convinced that had Titus atually read it, it would not have been raised. The pattern of changes in the frames of figure 6 doesn’t suggest an increase in sea-ice that would impede shipping in the summer to the degree implied by Titus, and it suggests that what’s happening now is odd in the historical context of 1933 to 2006. That’s a pattern I’ve come across in my reading about the Arctic.

    With the current (late July) sea ice area being lower than for any September minimum in the 1980s, odd is the order of the day up there.

    Comment by Chris R — 27 Jul 2011 @ 1:14 PM

  243. I don’t yet know if that is a permanent or seasonal ice shelf, so I will update when I know if this is a Big Deal or not.

    I believe it’s seasonal, ccpo.

    Comment by Neven — 27 Jul 2011 @ 1:45 PM

  244. Chris, your take on Mahoney seems to fit — that paper doesn’t support the claim Titus (or Max earlier) make. Brönnimann and others are citing it as data that can be useful in future attempts — but not as sufficient to determine the existence of — an Arctic trend. I think Titus and Max are eyeballing the pictures.

    Comment by Hank Roberts — 27 Jul 2011 @ 3:51 PM

  245. Hank Roberts (#117) and Spherica (Bob) (#119) seem to be more fond of casting stones than trying to understand what people actually post. I see no need to respond to them except to note that both posts are part of what I call the “shrill voices.”

    Now I will post something that will no doubt bring other voices out of the void which is the internet. I’ve been reading about three historical events in “scientific” history — (1) the “discovery” of N rays in France in the early part of thre 20th century, (2) the issue of eugenics which was pat of our culture in the 1920s and (3) the denial of plate tectonics by almost all scientists for decades.

    What do these three things have in common with global warming? Well — all were fiercely and passionately defended against the “denialists” of their day. Just as GW is. No room for dissenting data == consensus wins. For awhile.

    If they had made room, … well, mostly they didn’t.

    I continue to hold that the scientific evidence for global climate change is very strong. And so I preach (not literally) and write. But more and more “science” simply is ignored. People believe what they want to believe. Scientists are simply a bunch of wierdos and the opinions of “regular folks” are seen as stronger. I know scientists don’t want to hear this. But it seems, as I talk up global climate change to people, they immediately ask my scientific background and I can see their eyes glaze over when I respond. I have pretty much stopped responding on this question.

    As I once posted, I have no solution to offer to this problem. Only the observation that throwing more science at people is not only not working but may be counterproductive. And the quick responses to people such as me who not “true believers” — responses which are derogatory — does not help — it hinders.

    For instance — X says A is a fact. The usual response is that X is lying. Maybe he is, but saying so persuades nobody. The better response is to (respectfully) point out specific data which indicates A is not a fact — or, at least is not an established fact.

    BTW, my favorite book on the issue is WHAT IS THE~WORST THAT COULD HAPPEN. Yes — it is low level– but one I personally find persuasive in keeping me in the GW camp.

    Bye

    Comment by john burgeson — 27 Jul 2011 @ 4:13 PM

  246. John, what I wrote in 117 was a serious answer to your complaint.
    You said you have trouble explaining the sea ice chart to people.

    I said at 117, and I repeat:

    Robert Grumbine’s site teaches this stuff at the high school level, and he has what you need. Try there. http://moregrumbinescience.blogspot.com/

    Look at the site. He explains how the charts are created.
    He’s an expert in exactly this topic — sea ice.

    Comment by Hank Roberts — 27 Jul 2011 @ 4:54 PM

  247. @John McCormick says:27 Jul 2011 at 10:13 AM
    RE 235

    ccpo, please keep us informed regarding the movement of that massive new ice flow in the Fram Strait. Though the resolution was not adequate to tell for certain, it appeared to pop off on one day or less.

    Visited your web page. Nice piece of work!!

    John, I will as long as it stays within the area I’ve been tracking. The first large bit that broke off disintegrated very quickly. Perhaps these two pieces will, also. Overall, I don’t think this is all that important a story. See below.

    @Neven says:27 Jul 2011 at 1:45 PM

    I don’t yet know if that is a permanent or seasonal ice shelf, so I will update when I know if this is a Big Deal or not.

    I believe it’s seasonal, ccpo.

    Agreed. I went looking for images as soon as I posted that and updated the post yesterday.

    “UPDATE: Fun to watch, but it looks like the shelf is seasonal, at least in recent years.”

    I do wonder how long it’s been seasonal; might it be only since ’98, ’05 or ’07? That’s a very active area of sea ice movement and currents, so it seems likely it’s not a very long-term bit of ice.

    Comment by ccpo — 27 Jul 2011 @ 6:49 PM

  248. (3) the denial of plate tectonics by almost all scientists for decades.

    Continental drift != plate tectonics.

    Sorry, Burgy, try harder.

    Comment by dhogaza — 28 Jul 2011 @ 8:01 AM

  249. To Hank in #246

    You miss my point. I will try once again — I know that at age 80 I not as precise as I once was and my writing gets more vague with every passing year.

    A high school student in – say`- a physics class can, no doubt, understand the chart ok. as I can. Of course, by itself, it does not support the IPCC thesis — at best it is congruent with it. It says only that the ice in the Arctic is slowly changing.

    When presented to an adult, who last saw a science class (if he did) years ago, it is simply not
    a relevant argument at all. Mostly, he sees scientists as “those pointy head impractical kooks.” Sort of like that character in BACK TO THE FUTURE.

    Now the point is that the graph — at best — only says that over a few years span the Arctic ice cap has varied. Sure the trend is down, but this, in itself, is no particular evidence of anything. Everyone knows that “things change.”

    Hank — I am simply not a “true believer.” I know most everyone else here is — that’s OK. I support the IPCC because there is, to me, at least a 66% chance they are correct — and the precautionary principle says to not support them is folly. But I remain a skeptic.

    Here is another way of approaching the issue. The IPCC reports are based on 4 primary legs:

    1. CO2 is a greenhouse gas.
    2. CO2 levels are increasing, as we pour more of it into the air by burning fossil fuels.
    3. The planet is getting warmer.
    4. Complex (they have to be) models forecast the process is not sustainable.

    #1 is established.
    #2 is an experimental measure over some span of years and seems to be confirmed for at least one location. Probably more than one.

    The planet seems to be getting warmer. But the measures of this increase are all over the place, mostly over a few decades at best, and apparently (mostly) at the ragged edge of measurability. I’m not sure a few mm of sea level rise is really measurable, for instance.
    We are left then, with a heavy reliance on computer models. Models which are incomprehensible to a layman — and indeed to most science-educated people who are not involved with them. But all computer models (I have built a few of them) are based on a bunch of assumptions. And there are always some of these which must be taken on faith, for they cannot be measured.

    Finally — where are the fulfilled predictions/forecasts that the models have predicted? I am reminded of the predictions of more and more violent Atlantic hurricanes. Has’t happed. I know — not yet! But a few examples of successful forcasts made by the models (IN ADVANCE — NOT HIND CASTING) woyld certainly go a long way as talking points. But these have to be macro — ones anyone can see and understand. Perhaps I’ve missed these. If so, Dr. Schmitt (sp?) perhaps you can write one of your essays here which detail them and could be used as a talking point.

    Sorry for such a long response — I had not the time to make it shorter. John

    Comment by john burgeson — 28 Jul 2011 @ 8:33 AM

  250. john burgeson, you make some interesting points, but you seem to see things backwards.

    Yes, it took a long time for the theory of continental drift to be established. This is exactly similar to the idea of global warming, which was proposed over a century ago, and re-proposed many times since, all the way through the 20th century.

    But both theories had a problem. Continental drift lacked a mechanism, and global warming lacked observational evidence of an immediate problem.

    This situation didn’t last. In the case of continental drift, a mechanism was proposed, and geophysical evidence supporting that mechanism began to roll in. We know well what happened in the case of global warming: an accurate CO2 record, and a global temperature record that both showed that global warming was a current problem.

    And, in both cases, most of the hold-outs to the newly strengthened theory were old men, retired scientists and people who had stuck their neck out taking the opposing view when there was insufficient evidence. When their errors became obvious, they took refuge in denial.

    So, yes – plate tectonics is an excellent analogy, but not in the way you seem to believe.

    A new scientific truth does not triumph by convincing opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.
    Max Planck, A Scientific Autobiography and Other Papers, 1949

    Comment by Didactylos — 28 Jul 2011 @ 10:02 AM

  251. Burgy says: “where are the fulfilled predictions/forecasts that the models have predicted?
    here’s a (partial) list – if you’re sceptical friends are looking for weather forecasts, climate models are not what you want, just pay attention to the news.

    Do you have a reference for the “predictions of more and more violent Atlantic hurricanes”? And is that “(more and more) violent”, or “more, and (more violent)”?

    Comment by flxible — 28 Jul 2011 @ 10:14 AM

  252. Didactylos @ 250, as I recall, that offhand remark of Planck’s did not stand up to an actual study.

    Comment by Pete Dunkelberg — 28 Jul 2011 @ 11:12 AM

  253. If it is the holy duty of every diagram connected with climatology to “prove global warming” and of every such in biology to “prove evolution”, things may start to get boring soon. Even absent, some sort of people seems too dictate the discussion to an extent they should not be entitled to

    Comment by Marcus — 28 Jul 2011 @ 11:26 AM

  254. REPOST: Previous was not properly formatted and difficult to follow. Please post this, instead.

    @249 john burgeson says:
    28 Jul 2011 at 8:33 AM

    understand the chart ok. as I can. Of course, by itself, it does not support the IPCC thesis — at best it is congruent with it. It says only that the ice in the Arctic is slowly changing.

    No, it says the ice is changing suddenly, massively and, if you dismiss climate change, without reason. That’s an absurd hypothesis, isn’t it, that the ice would be disappearing without reason? And this is where your argument reaches into absurdity, along with every other denialist out there. It is not enough to say you don’t accept the most logical and reasonable interpretation of a huge array of data, you must provide a reason beyond “i just don’t think so” and, more so, must offer an alternative explanation.

    What is your alternative explanation? Too many yellow twinkies absorbing sunlight? Too many farts? We know it isn’t the sun, itself, or volcanism, or the position or inclination of the planet, so what is it? Occam’s Razor applies: if you know adding GHGs to the atmosphere will raise the temperature of the atmosphere, and by roughly how much, and that happens, *and* there is no other explanation, “I just don’t think so” doesn’t cut it.

    When presented to an adult, who last saw a science class (if he did) years ago, it is simply not a relevant argument at all.

    Do not confuse the quality and vastness of the science with the ignorance of the populace. If that chart does not scare the bejeezus out of you, it is ignorance at play, not a lack of relevancy in the science. What that chart says, if you don’t accept the science, is that the Arctic is rapidly, massively changing without reason. That’s even scarier than attributing it to climate change. The implications are the planet is so vastly variable the chances of maintaining civilization are pretty much slim and none. Or do you not understand the chart to represent very large changes, not small ones?

    Mostly, he sees scientists as “those pointy head impractical kooks.”

    This is a very recent characterization and is the direct result of propaganda. We are now blaming the science and scientists for the propaganda against them? It is the information that is supposed to cut through perceptions. There’s the data. If the data and implications of it do not cut through the biases, what can? We are left with logic via, as you say, the Precautionary Principle. But the typical American is no more aware of nor impressed by the precautionary principle than they are climate science. No, we must speak the facts and their implications, and do so unambiguously. If there is a problem with the science it is in the disconnect between scientific communication of probability and risk and the colloquial understanding of them. There is nothing in the data or its interpretation that let’s anyone off the hook for their supposed skepticism. No, there is nothing to support skepticism, so it is more properly labeled denial. Given the denial is manufactured, all the more so.

    You are the end user. You are responsible for your ignorance, not the science. If you can look at a ratio of 1000′s:0 in terms of scientific papers on the topic and perceive that as significant reason to doubt, the problem lies with you, not the science. In what other field of study is such an absurd ratio accepted as good reason for doubt?

    Now the point is that the graph — at best — only says that over a few years span the Arctic ice cap has varied. Sure the trend is down, but this, in itself, is no particular evidence of anything. Everyone knows that “things change.”

    False. Calling decades a few years is disingenuous, at best. You are de-contextualizing the data. Does this chart stand alone as the only evidence of climate change? No. Is it ever appropriate to discuss one graph as being conclusive or inconclusive of climate science? No.

    This chart is, for one, many thousands of data points, not a single data point. It is a decades-long trend, though that chart only shows a part of it, it is not fair to pretend the prior years do not exist. Additionally, the chart shows massive changes, not small ones. If you are presenting such a chart to people de-contextualized, again, the fault is with you, not the science.

    Also, things are not merely changing, they are changing at rates and amplitudes never seen before – and according to you for no reason, jsut because.

    I am simply not a “true believer.”

    Who is? Do not attempt to imply this is about belief or religion. That unacceptable.

    I support the IPCC because there is, to me, at least a 66% chance they are correct — and the precautionary principle says to not support them is folly.

    Where does 66% chance come from? The risk is actually 100%. The planet is warming, it is unambiguous and the only cause we can find is anthropogenic. The risk is 100%. There is zero evidence in support of any other conclusion. (There are negative feedbacks and natural variation, but those are accounted for. They do not explain the massive excursion in GHG concentrations and warming – along with myriad other lines of evidence.) The risk is 100%.

    But I remain a skeptic.

    Yet, there is absolutely nothing to support that. We typically call it a belief or conclusion that has no support or evidence of any kind a delusion. Your argument does not work against climate science, it decreases our trust in your ability to reason. I do not mean this pejoratively, i am simply stating a fact. If you can look at the ratio of data in support of a dominant anthropogenic climate forcing vs the data contradicting that, 100%:0%, and conclude there is a reasonable doubt, what are we left to conclude? How do you defend this?

    Of course, the typical way is as you have above: take a very small part of the total evidence and quibble with it. Denial and “skepticism” as it relates to climate always uses this tactic. I have never seen a denial of climate science that addressed the full range of the science. The reason for this is obvious: it was stated succinctly by those sewing doubt that doubt was their objective. They know full well that if they attempt to address the issue on the merits alone their efforts would fail. So they attack scientists’ credibility and cherry pick data then distort it.

    Here is another way of approaching the issue. The IPCC reports are based on 4 primary legs:

    1. CO2 is a greenhouse gas.
    2. CO2 levels are increasing, as we pour more of it into the air by burning fossil fuels.
    3. The planet is getting warmer.
    4. Complex (they have to be) models forecast the process is not sustainable.

    #1 is established.
    #2 is an experimental measure over some span of years and seems to be confirmed for at least one location. Probably more than one.

    False. Measurements are taken in more than one location and the atmosphere is well-mixed. Spinning this as doubtful is a bit like going to a swimming pool, dipping you toe in the water and saying, “Well, it’s OK here, but we can’t know for sure till we dip our toes in every square foot of surface area. THEN you can jump in, kids!”

    The planet seems to be getting warmer. But the measures of this increase are all over the place, mostly over a few decades at best, and apparently (mostly) at the ragged edge of measurability.

    No, the planet *is* getting warmer. This is unambiguous. The measures are widespread and robust. Additionally, they match predicted outcomes from long ago and current scenarios. To claim it is at the “ragged edge” is inaccurate and pejorative.

    I’m not sure a few mm of sea level rise is really measurable, for instance.

    So? Do you have reason for this beyond your own incredulousness?

    We are left then, with a heavy reliance on computer models.

    You have set up a rather limp straw man argument:

    1. There’s not much data.

    False.

    2. The data is unreliable.

    False.

    3. I’m not convinced (and it’s your fault, not mine.)

    Logical fallacy.

    4. The data is unreliable so only models support climate science.

    Simply absurd. The data is not only reliable, it is vast. You have absolutely no way to support this claim.

    Models which are incomprehensible to a layman — and indeed to most science-educated people who are not involved with them.

    Logical fallacy: I don’t understand it, so it can’t be trusted. Yet, we get in airplanes, drive cars, watch TV, use medicines, buy complex equipment… none of which we understand ourselves.

    But all computer models (I have built a few of them) are based on a bunch of assumptions.

    That’s why they are called “models” and not “future reality projections.” And yet another straw man: There are assumptions about the future in things designed…. to make assumptions about the future, so they are meaningless.

    But let us back up to the core of your claim: climate science = models. We already dealt with your dismissal of the data, which is an untenable position. Your argument rests on that false assumption, so crumbles from that. But, additionally, models are not climate science. They are exactly what they are said to be: guesses about the future based on what we know now. They do not generate the data, they are fed the data.

    It is both illogical and foolhardy to say we should have a blank, impassable wall at the immediately present moment and not attempt to look forward. Models offer the only way we have of determining what our future choices might be. It is absurd to imply their inherent uncertainty si a flaw and reason to not use them. They are not predictors, they generate possible scenarios. The decisions still lie at the very human level of planning and decision making.

    Finally — where are the fulfilled predictions/forecasts that the models have predicted? I am reminded of the predictions of more and more violent Atlantic hurricanes. Has’t happed.

    False. Your statement as to violence – power – is simply false and your statement about frequency a Red Herring. Hurricanes do show a trend toward more powerful storms. The issue of frequency was abandoned a few years ago. There was some suggestion in the data frequency might be an issue, but ongoing study has largely dispelled that. Why do you raise a non-issue here?

    I know — not yet! But a few examples of successful forcasts made by the models (IN ADVANCE — NOT HIND CASTING) woyld certainly go a long way as talking points. But these have to be macro — ones anyone can see and understand. Perhaps I’ve missed these.

    You have not missed them, you are pretending they do not exist.

    1. Increased temperatures.
    2. Arctic Amplification.
    3. Warming greater at night than in the day.
    4. Warming greater in winter than in summer.
    5. Biota moving in response to temps.
    6. Increased humidity globally.
    7. Heavier rain events.
    8. Increasing frequency and magnitude of floods.
    9. Increasing frequency and magnitude of droughts.
    10. Arctic Sea Ice melt.
    11. Antarctic Ice Cap melt.
    12. Glaciers melting.
    13. Increased flooding due to glaciers melting.
    14. Increasing extinctions due to habitat and temperature changes.
    15. Increased precipitation at the center of the Greenland and Antarctic Ice Caps.
    16. Ocean acidification.
    17. Rhythms of biota out of whack resulting in declines in populations and possible extinctions.
    18. Diseases moving to areas before not found.
    19. Invasive species disrupting ecosystems.
    20. Warming of the lower atmosphere.
    21. Cooling of the upper atmosphere.
    22. Coral bleaching.
    23. Shorter winters, longer summers.
    24. Methane/CO2 emissions from permafrost/clathrates.

    Shall I go on?

    It is a credit to the insight of denial organizations that they have never gone after Arctic ice loss other than to claim it is balanced by Antarctic sea ice gain – ignoring that the two regions are completely different in their geographies, mechanics, and interactions with the rest of the planet. It is easy to claim some polar bears are still alive, so climate change can’t be real. It is not so easy to deny the very obvious photos and other images showing the very real, undeniable reductions in sea ice. Denialists never go there because they cannot spin it or make it seem like voodoo. It is interesting that you do not deny the DATA, but claim the presentation of the data means nothing.

    Logical Fail: The is ice melting, but a chart of that is meaningless.

    Denial Fail.

    Comment by ccpo — 28 Jul 2011 @ 11:34 AM

  255. Getting OT here, but since the continental drift story is one of the favorite denialist “Galileo-class” arguments …

    Yes, it took a long time for the theory of continental drift to be established…But both theories had a problem. Continental drift lacked a mechanism

    The fact that the continents fit together more or less like a jigsaw puzzle was obvious to many for a long time.

    The problem with continental drift wasn’t that it presented this observation with no proposed mechanism.

    The problem with the “theory” (more of a hypothesis, really) was that a mechanism *was* proposed, but that mechanism was physically impossible. It was properly rejected by most geologists (no one rejected the obviously fact that continents appear to fit like jigsaw puzzle pieces).

    Plate tectonics didn’t lead to the hypothesis of continental drift to be adopted. Rather, it offered a mechanism by which the continents could, indeed, move around. It’s more proper to state that it *replaced* continental drift – no one accepts any of the mechanisms previously proposed to explain the jigsaw-puzzle fit of continents.

    Once sea floor spreading was observed and the implications understood and plate tectonics put forward as a result, adoption was pretty rapid by scientific standards … of course there are geologists today (emeritus almost to a man/woman) who still reject it, but we have geologists who believe the sun is iron and CO2-forced warming a myth, too :)

    The “continental drift” bit is really a relatively unimportant consequence of plate tectonics, which explains a bunch of stuff …

    Comment by dhogaza — 28 Jul 2011 @ 12:42 PM

  256. Clouds are key and what I’ve seen so far was much weaker ice surviving the onslaught of summer because of cloudier conditions than say 2007. This does not stop the ice from disintegrating faster than 2007, essentially proving ice volume estimates as being spot on. I still look at the over all picture, carefully along Laptev sea, I think that Fram Strait will have a twin ice dumping channel if ice melts further there.

    Comment by wayne davidson — 28 Jul 2011 @ 1:55 PM

  257. On dhogaza’s OT point: this is widely accepted, but it’s not even a good thumbnail sketch. For one thing, Arthur Holmes proposed something very like the current mechanism (mantle currents) in the ’30s. I suspect that many geologists were queasy about relying on a hypothetico-deductive approach when they had no way to observe the proposed mechanism at work (great emphasis was placed on efforts to directly measure drift; similarly many geologists resisted the ice-age hypothesis and then accepted it after a field-trip introducing them to direct evidence of glaciers at work).

    Oreskes’ The Rejection of Continental Drift gives a very nice account of the debate among U.S. geologists.

    Comment by Bryson Brown — 28 Jul 2011 @ 4:24 PM

  258. “The story of Blondlot is a story of self-deception among scientists. Because many people have the misguided notion that science should be infallible and a fount of absolutely certain truths, they look at the Blondlot episode as a vindication of their excessive skepticism towards science….”
    http://www.skepdic.com/blondlot.html

    Comment by Hank Roberts — 28 Jul 2011 @ 6:57 PM

  259. On the subject of the JAXA SEI figures, unless there is an absolutely enormous INCREASE in extent, when the data for the 28th July is posted, 2011 will replace 2007 as having the lowest recorded July average. This will therefore join with the lowest monthly averages recorded in June 2010, November 2010, December 2010 and January 2011 in proving that Arctic Sea Ice is unambiguously recovering. (Or perhaps not!)

    If one looks at average annual extent, the 2007 figure (9.966 million sq km) is unsurprisingly lowest by some margin. What may surprise some is that although 2008 is in 2nd place for both the September Minimum and September Average, it has the highest annual average out of the latest 6 years. With an annual average of 10.22 million sq km, 2006 is, at present, second lowest in this respect.

    Taking a daily incrementing average from the 1st January each year until today’s date, then 2006 currently has the lowest such figure (11.849 million sq km as of 28th July). By the 24th August, the equivalent 2007 figure converges on and surpasses 2006 – and 2007 then remains lowest until the year end. (NB Until the end of January, 2011 was of course lowest, but the 2006 figures “retook” lowest place from the 1st February onward.)

    However, irrespective of the weather over the remainder of the melt season – and indeed till the year end – things will be different this year. Unless I have cocked up the spreadsheet, on the 3rd August (+/- 1 day) the 2011 figure will overtake (perhaps “undertake” is more accurate?) the equivalent 2006 figure.

    My crystal ball skills are inadequate to predict how the year-end averages will pan out, but it is difficult to see how 2011 will fail to at least replace 2010 as 3rd lowest annual average, and will probably also replace 2006 in second place.

    If the average daily delta over the next 5 weeks is just 37,500 sq km, then the August 2011 average will be the second lowest thus far. (Assuming an evenly distributed drop rate – this projection would obviously fail if the drop profile was back-loaded.)

    With an average daily drop rate of 48,700 over the next 5 weeks (irrespective of the profile), 2011 would also have the second lowest end-of-August extent. Intriguingly, with such a delta, this would also see the August month end figure drop below the psychologically important (but otherwise relatively arbitrary) barrier of 5 million sq km for only the second time.

    Personally speaking (that has got to be a tautology) I really hope 2011 fails to beat the 2007 minimum. The weather conditions in 2007 were so remarkably conducive to a low minimum – 8 weeks of averaging 91,000 drops, bracketed with two weeks either side averaging 45,000 between them – that we at least seemed to be destined to wait quite a few years before seeing its like again.

    If 2011 is already threatening to beat this record, I fear we are running out of time.

    Comment by bill the frog — 28 Jul 2011 @ 8:22 PM

  260. @bill the frog.
    Nice. Thanks for that.

    @State of the Arctic: Northwest Passage OPEN. Appropriate caveats within:

    http://aperfectstormcometh.blogspot.com/2011/07/current-state-of-arctic-sea-ice_29.html

    You heard it here first. (Lie if you didn’t.)

    Comment by ccpo — 29 Jul 2011 @ 12:20 AM

  261. Getting hotter and hotter. Yet another feedback…

    http://www.bbc.co.uk/news/science-environment-14306781

    Comment by ccpo — 29 Jul 2011 @ 12:43 AM

  262. On the Cryosphere Today image, you can see an island of ice between Canada and Greenland fairly far South. Is that the ice island coming Petermann glacier?

    Comment by Juliette — 29 Jul 2011 @ 4:01 AM

  263. The structure between bering strait and north pole resembles a vortex… can that be, or is this a purely optical illusion?

    Comment by Marcus — 29 Jul 2011 @ 6:44 AM

  264. Juliette @ 262, No that’s not the Petermann Ice Island. It’s just a small amount of residual sea ice sitting in a slow gyre caused by currents in Baffin Bay. It will probably melt out fairly soon.

    Petermann Ice Island broke into a couple of large sections which have been slowly shrinking as they shed icebergs. Of the two major parts left, one is currently in the middle of the strait between Devon Island and Baffin Island, and is slowly being pushed towards the Northwest Passage area. This doesn’t appear on the CT maps (if it did it would only be a couple of pixels), but it an be seen on NASA’s MODIS satellite pictures at higher magnifications (eg 250m/pixel).

    The other part has been drifting down the coast of Labrador for several months and is currently roughly level with the northernmost point of Newfoundland. Again, this is not shown on the CT map but can be seen on satellite photos. It’s becoming something of a tourist attraction and search engines should link you to recent details of its location.

    Comment by FrankD — 29 Jul 2011 @ 10:02 AM

  265. @ John Burgeson – various

    John,

    Very few people with a genuine interest in science would have a bad word to say about anyone demonstrating GENUINE scepticism (or skepticism, if you were taught to spell it that way in skool). However, when this word (irrespective of its spelling) is prefixed by the modifiers “climate change”, it invariably becomes an oxymoron of truly singular status.

    In the deniosphere, claims are rife about “Arctic sea ice was as low in the ’40s as it is now, and it was just coincidence that satellite telemetry began in 1979 when, by mere coincidence, the Arctic ice was at the maximum in a 60 (or insert number of your choice) year cycle.”

    However, there are a few weaknesses with that story. Let’s start with the satellite chestnut. It is of course true that many sites show data from 1979 – that was indeed the start of the multi-channel microwave systems, such as SMMR and progressing to SSM/I, SSMIS and AMSR-E.

    However, take a closer look at the University of Bremen site. In particular, have a quick decko at the baseline dates. In the Arctic, this runs from ’72 – ’08 and ’73 – ’08 for the Antarctic. Is this a typing error, or, just possibly, might there be some data to back this up? Could it perhaps have something to do with the fact that there were single channel ESMR devices on the Nimbus satellites? The ESMR dataset is available from NSIDC at … ftp://sidads.colorado.edu/pub/DATASETS/nsidc0192_seaice_trends_climo/esmr-smmr-ssmi-merged/gsfc.nasateam.extent.1972-2002.n

    Anyone looking at this dataset will see that, from 1972 – 1978, the average September extent for the Arctic ranged between 7.13 – 7.50 million sq km. As for the 1979 figure – how about 7.07? In other words LOWER than the previous 6 years, and NOT at a transient maxima as claimed in many quarters. (It’s getting to be squeaky bottom time for that 60 year cycle conjecture, isn’t it?)

    The September extent figure for the Arctic is currently declining at ~11%/decade, or about 35% since the putative ’79 start date. Therefore, if the extent was as low in the ’40s (or whenever) as now, it must have grown by over 50% from this supposed minima sometime during the interregnum. Now surely somebody would have noticed this by the ’60s or ’70s and produced a scientific paper remarking on the fact?

    Unfortunately, and I am sure it must just be my limitations, I have yet to find such a paper. On the other hand, what I have seen is a study available on Cryosphere Today. This is by Chapman and Johnson entitled “Analysis of Arctic sea ice fluctuations 1953-77″, and it was published in the Journal of Physical Oceanography. Chapman & Johnson do record a less than earth shattering increase of, if memory serves, around 80,000 sq km over the 25 year period of the study.

    This, as others have observed, does not tie in well with your memory of hearing about some whole scale increase in Arctic sea ice during the ’50s & ’60s.

    It’s your call which ever you think might be the more reliable.

    Comment by bill the frog — 29 Jul 2011 @ 12:24 PM

  266. A lesson for those who don’t worry about current Arctic ice conditions, where there is no ice, Canadian Archipelago, its very hot, yes hot, often 10 degrees above average.
    Where the ice still lies, its much cooler:
    http://www.weatheroffice.gc.ca/data/analysis/jac18_100.gif

    A world without Arctic sea ice would be extremely different.

    Comment by wayne davidson — 1 Aug 2011 @ 11:35 AM

  267. Pituffik, Greenland (Thule Air Base)surpassed record high temp by 11 degrees today. 62F for a high.

    Comment by Jathanon — 1 Aug 2011 @ 11:39 AM

  268. #266-7:

    What strikes me, looking at the Nunavut temps (ie., the Canadian Eastern Arctic) is not so much the maxima, though there are a few splashy examples of high maxima. It’s the amazingly consistent way in which the daily minima are running about 3 C above norms–there are only a very few exceptions to that pattern. And if I recall correctly, the same was true throughout much of last summer, too.

    Most Nunavut stations have normal max/min and a 7-day forecast available here:

    http://www.weatheroffice.gc.ca/forecast/canada/index_e.html?id=NU

    Comment by Kevin McKinney — 1 Aug 2011 @ 12:05 PM

  269. #268 Kevin, that is in part because of the lack of sea ice. Now the flow for the main pack over the Arctic Ocean is key, I dont think the low pressure north of Alaska will last the same way as last year.

    Comment by wayne davidson — 1 Aug 2011 @ 2:07 PM

  270. To Bill the frog:

    You must have me confused with some other poster.

    Comment by john burgeson — 2 Aug 2011 @ 4:28 PM

  271. To John Burgeson (@270)

    “you must have me confused with some other poster”

    John, profuse apologies. My only defence is rapidly encroaching senility. I had 3 blog responses buzzing around in my head and managed to mangle them. (2 for RC and one for that stalwart champion of logical thought – the UK’s Sunday Mail)

    My comment (265) was meant for Titus, and related to his putative memories of Arctic Sea Ice growth during the ’50s and ’60s.

    One of the responses I had in mind was to your comment number 245, and that is why your name was floating around in what is left of my grey matter. The rather delayed point I was trying to make to you was as follows…

    You may wish to reconsider the validity of the analogy you are hoping to draw between AGW consensus and the approach of the scientific establishment to the various discoveries that you enumerated.

    If you are not already aware of its existence, I would strongly recommend reading Spencer Weart’s excellent “the Discovery of Global Warming” on the AIP website. In particular, have a look at the section called “the Carbon Dioxide Greenhouse Effect”. This, as you work through it, provides a very illuminating timeline and relates how, until the ’70s & ’80s, the scientific consensus was that anthropogenic CO2 emissions were largely insignificant in terms of climate change. (It’s also well worth perusing the bit about Roger Revelle.) In other words, the view of mainstream science has already performed a 180. You don’t often here that being talked about in the deniosphere – it causes too much of a cognitive dissonance.

    Most people on this site are well aware of how scientific orthodoxy is portrayed as an inflexible barrier to new ideas; a better perspective perhaps is to view scientific consensus as a sort of garbage collector designed to stop us from getting smothered in trash.

    Sorry again about getting my knickers in a twist. btf

    Comment by bill the frog — 3 Aug 2011 @ 5:06 AM

  272. Titus (@161, 212 & 229)

    Hi Titus,

    A couple of days ago, I tried to respond to your various posts about supposed Arctic Sea Ice growth in the ’50s & ’60s, but managed to wrongly address this to John Burgeson. (See his comment 270 and my subsequent response.)

    My comment (265) should have been addressed to your good self, and was intended as a more general supplement to the detailed responses already made by Chris R

    Sorry about the rank incompetence btf

    Comment by bill the frog — 3 Aug 2011 @ 5:14 AM

  273. Interesting developments over the last few days. Looks like an unprecedented Summer inswinger. Any clues on what might be driving this?

    Comment by Paul S — 3 Aug 2011 @ 7:14 AM

  274. Paul S @273

    Depending upon one’s proclivities, this could be ascribed to …

    a) natural cycles

    b) divine intervention (Sorry, that should, of course, have been Divine intervention)

    c) thin, fractured ice being spread out over a larger “area”, or more properly, “extent”, by wind/wave action. (Slight problem with nomenclature there – but I think it’s reasonable to expect that nearly everyone on this site understands the difference between the terms.)

    Think of spreading jam over just part of a slice of bread. Now spread it over the rest of the slice. You have increased the area (extent) but you ain’t got more jam.

    There was a vaguely analogous slow down last year between about the 5th – 15th July, but not as extreme as being witnessed at the present. It will be interesting to see what the average delta for August has reached by about the middle of the month.

    Comment by bill the frog — 3 Aug 2011 @ 9:11 AM

  275. I’m going with spreading jam. I just finished my predictions for sea ice.

    http://aperfectstormcometh.blogspot.com/2011/08/current-state-of-arctic-sea-ice-arctic.html

    Comment by ccpo — 3 Aug 2011 @ 11:16 PM

  276. It seems the normal Arctic Gyre is returning:

    http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html

    this greatly contrasts with 2010. And favors a great pack ice loss.. Clouds again played a significant role, but in this case the returning beaufort Gyre will accelerate flushing of very weak ice. Again small Russian Islands play a role in adverting an even greater loss. Remains to be seen wheter there is an ice bridge north of Laptev sea, or rotten loose ice.

    Comment by wayne davidson — 6 Aug 2011 @ 3:18 PM

  277. Andy Revkin:
    http://dotearth.blogs.nytimes.com/2011/08/08/on-arctic-sea-ice-and-warmth-past-and-future/

    Comment by Ibrahim — 9 Aug 2011 @ 10:46 AM

  278. Am I right in thinking that the eggshell ice we are mostly seeing these days is *less* prone to being moved by winds and currents (especially winds)?

    The reasoning is that the ice has few (if any) pressure ridges, and the freeboard is less, leaving the wind with little to push against.

    Comment by Didactylos — 9 Aug 2011 @ 4:10 PM

  279. Arctic sea ice extent isn’t everything. In particular it isn’t sea ice volume, which is low.

    Is the not so thick ice harder to blow around? It doesn’t stick up so much, or down so much. This summer the winds have tended to break it up somewhat and move it around the Arctic, but not push it out through the Fram Straight.

    Comment by Pete Dunkelberg — 9 Aug 2011 @ 6:17 PM

  280. Didactylos @278 : That’ll be one of those negative feedbacks I keep hearing about.

    Comment by Cugel — 9 Aug 2011 @ 6:29 PM

  281. This summer the winds have tended to break it up somewhat and move it around the Arctic, but not push it out through the Fram Straight.

    When conditions have been right this year, a lot has been blown out through the Fram Straight, the result being that the Greenland Sea has had higher than recently normal extent at times for the date. It all melts, of course …

    Comment by dhogaza — 9 Aug 2011 @ 7:56 PM

  282. “When conditions have been right….” – tautology. ;)

    Comment by Pete Dunkelberg — 9 Aug 2011 @ 10:19 PM

  283. North Pole to Laptev sea ice bridge seems to be collapsing, and there appears new ice flowing out between Severnaya Zemlya and Franz Josef islands. There is a near consistent Low pressure modeled for that area. For this reason 2007 ice extent minima is poised to be severely exceeded.

    Comment by wayne davidson — 10 Aug 2011 @ 8:01 AM

  284. Let’s have a look on the today’s MIT spotlight:
    http://web.mit.edu/

    [Response: The actual story is here. Some statements are a little weird though - all the AR4 models had sea ice dynamics affected by the winds and currents for instance - but one should probably wait until the actual paper comes out to see what is really being claimed. - gavin]

    Comment by seaice — 10 Aug 2011 @ 8:34 AM

  285. “When conditions have been right….” – tautology. ;)

    Refutation. You’ve claimed that under such conditions, ice hasn’t been flowing out of the Fram Straight, possibly because being thinner it doesn’t “stick up so much”.

    You’re wrong. When conditions have been right, substantial amounts of ice have been flowing out of the Fram Straight, regardless of how high it “sticks up”. The last several days happen to have seen the conditions be … tautological, so to speak … and yes, the ice is on the move.

    Comment by dhogaza — 10 Aug 2011 @ 8:41 AM

  286. # 285 dhogaza tells me “You’ve claimed that under such conditions, ice hasn’t been flowing out of the Fram Straight, ….”

    actually, I didn’t. We must be misunderstanding each other.

    Comment by Pete Dunkelberg — 10 Aug 2011 @ 10:45 AM

  287. Pete:

    We must be misunderstanding each other.

    Hmmm…

    This summer the winds have tended to break it up somewhat and move it around the Arctic, but not push it out through the Fram Straight.

    Seems clear to me, along with your guess that it’s not due to different wind conditions, but rather the ice “not sticking up” high enough to be pushed along by it.

    Whatever.

    Comment by dhogaza — 10 Aug 2011 @ 11:38 AM

  288. @ 284: http://web.mit.edu/newsoffice/2011/arctic-ice-melt-0810.html

    “The Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report, released in 2007, forecasts an ice-free Arctic summer by the year 2100, among other predictions. But Pierre Rampal, a postdoc in the Department of Earth, Atmosphere, and Planetary Sciences (EAPS), and colleagues say it may happen several decades earlier.”

    That’s automatic. If there is a good chance of an ice free Arctic summer by 2100, then of course it “may” happen in 2100 plus or minus a few decades.

    So I think the new study says “probably sooner rather than later.” But this is hardly news. Isn’t that already published?
    I mean, even besides by the Navy. As we know, Maslowski of the Naval Postgraduate School has an Arctic regional supercomputer model and finds that the summer sea ice is going down within this decade.

    http://www.sustain.hokudai.ac.jp/researchers_in_network/_maslowski_wieslaw/index.php

    http://soa.arcus.org/sites/soa.arcus.org/files/sessions/1-1-advances-understanding-arctic-system-components/pdf/1-1-7-maslowski-wieslaw.pdf

    Why isn’t this given more credit? After all, sea ice is vanishing quite a bit faster than the global models forecast, isn’t it?

    Anyway, the new thing about the new study (as usual ignore the press release) is I think a new model of Arctic processes. Evidently this new model partly catches up with actual Arctic events.

    Comment by Pete Dunkelberg — 10 Aug 2011 @ 12:58 PM

  289. dhogaza @ 287, “You are misunderstanding me. I am trying to connect to Connecticut but you cut my connection.” Go back to 278 and start over.


    Then observe that I replied [279] “[the thinner ice] It doesn’t stick up so much, or down so much. This summer the winds have tended to break it up somewhat and move it around the Arctic, but not push it out through the Fram Straight.”

    The thinner ice does not stick so much or down so much = the question of whether it is easier to move by wind is not directly settled by the previous observation that it doesn’t stick up so much.

    continuing …

    This summer’s winds have not been all in one direction by a long shot. Instead the ice has been blown around rather than in a line, including rather than in a line out the Fram Straight.

    OK?

    Comment by Pete Dunkelberg — 10 Aug 2011 @ 1:29 PM

  290. #278–

    Am I right in thinking that the eggshell ice we are mostly seeing these days is *less* prone to being moved by winds and currents (especially winds)?

    The reasoning is that the ice has few (if any) pressure ridges, and the freeboard is less, leaving the wind with little to push against.

    I’ve no scientific support for this, but my reasoning leads to the opposite conclusion: since, as we know, only about 10% of the ice is above water, and since wind directly operates only above the waterline (obviously), the ice below exerts more drag relative to the force of the wind for larger floes, than for smaller ones. Basically, bigger floes need to move water out of the way.

    Forces such as tides and currents are, of course, another story.

    Comment by Kevin McKinney — 10 Aug 2011 @ 4:50 PM

  291. FWIW, I’m quite convinced that we’ll see a seasonally ice-free Arctic (by Dr. Maslowski’s definition) long before mid-century. The declining trend in volume, compared with advection of warm Pacific water–presumably relatively constant–(and figuring a modest boost from albedo and water vapor feedbacks) leaves little room for any other conclusion in my (rather simplistic) mind.

    Comment by Kevin McKinney — 10 Aug 2011 @ 4:57 PM

  292. Didactylos, #278.

    Sea ice is becoming more mobile as it gets thinner:
    eg. http://dosbat.blogspot.com/2011/08/sea-ice-drift-speeds-in-arctic.html
    The wind drags on the rough surface of the ice, protrusions from ridging are not a major factor. Thinner ice having less mass and less mechanical strength is more easily moved.

    Re the Fram Strait,

    Fram Strait export was high during 2007-2008 (exceptionally so), but most of the studies I’ve read find no trend. e.g. Spreen et al 2009. I have recently read a paper that referred to a personal communication from Ron Kwok confirming no recent trend in Fram Strait flux (but I can’t put my hands on the paper, lost in a pile, and can’t recall if that was area/volume flux – sorry – a bit useless I know).

    Comment by Chris R — 11 Aug 2011 @ 1:55 PM

  293. Didactylos,

    The sea ice is moving more quickly according to one recent study:
    http://dosbat.blogspot.com/2011/08/sea-ice-drift-speeds-in-arctic.html
    The thinner ice is actually more prone to movement due to less mass, less mechanical strength and in summer more cracks.

    Fram Strait export shows no trend, e.g. Spreen at al 2009 “Fram Strait Sea Ice Volume Export Estimated Between 2003 and 2008 From Satellite Data.” I have read a paper recently that includes reference to a personal communication from Ron Kwok stating no recent trend – but I can’t recall which paper (I’ve read a lot in the last few weeks).

    If anyone can cite papers showing a trend in Fram Strait flux (excluding the exceptional flux of 2007/08), I’d be interested.

    Comment by Chris R — 11 Aug 2011 @ 2:09 PM

  294. Pete:

    This summer’s winds have not been all in one direction by a long shot.

    True. Why would they be, and during which summer has it been (depends on how you precisely define “a long shot”, presumably).

    Instead the ice has been blown around rather than in a line, including rather than in a line out the Fram Straight.

    OK?

    Nope, as I’ve said several times, a considerable quantity of ice has been blown out of the Fram Straight into the Greenland Sea, with the result that for some periods of time this summer the extent anomaly for that area has been high due to all the ice blown into it (which then has melted).

    The last few days, as I’ve said several times, has seen quite a bit of movement out of the Fram Straight.

    What’s so hard to understand about that?

    Comment by dhogaza — 11 Aug 2011 @ 2:50 PM

  295. > volume, which is low

    No kidding.

    Has anyone shown the correlation over time for these different measures — area, extent, and volume? Seems to me intuitively they ought to end up at zero all about the same time.

    Here’s the volume:

    http://psc.apl.washington.edu/wordpress/wp-content/uploads/schweiger/ice_volume/SPIOMASIceVolumeAnomalyCurrentV2_CY.png?%3C?php%20echo%20time()?

    Neven’s blog has the color-by-number version:
    http://neven1.typepad.com/.a/6a0133f03a1e37970b015390673095970b-800wi
    from http://neven1.typepad.com/blog/2011/08/piomas-july-2011.html

    Neven also has on the same page the exponential-trend with color-by-number. Joe Romm has picked that up; it’s the most dramatic image.

    Those needs to be explained — maybe with a pointer to some definitions page I don’t know about. Something like:

    JAXA Extent and Area:

    “The sea-ice extent is calculated as the areal sum of sea ice covering the ocean where sea-ice concentration (SIC) exceeds 15%…. SIC data could have errors of 10% at most ….

    … 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. The former is defined as the areal sum of sea ice covering the ocean (sea ice + open ocean), whereas the latter “area” definition counts only sea ice covering a fraction of the ocean (sea ice only). Thus, the sea-ice extent is always larger than the sea-ice area.”
    http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

    PIOMAS volume:

    “… For the ice volume simulations shown here, sea ice concentration information from the NSIDC near-real time product are assimilated into the model to improve ice thickness estimates ….”
    http://psc.apl.washington.edu/wordpress/research/projects/arctic-sea-ice-volume-anomaly/

    Comment by Hank Roberts — 11 Aug 2011 @ 4:20 PM

  296. For your info, I found this on the web page of the lead author of http://web.mit.edu/newsoffice/2011/arctic-ice-melt-0810.html

    http://web.mit.edu/~rampal/rampal_homepage/Publications.html

    According to those papers, sea ice not only accelerates, but also deforms and breaks up much more than before
    what do you think?

    Comment by seaice — 12 Aug 2011 @ 12:32 AM

  297. @ Fram Strait I tried tracking this on my blog, but cloudiness and ice breaking up make this really hard for days at a time and you end up just picking new ice to track not sure whether it’s what you were tracking or not, ofttimes.

    But this also tells you something. 1. The ice breaks up rather quickly at times. 2. The ice moves quickly enough to make it hard to track as it deforms.

    However, I also found floes moving northward closer to the Greenland coast and southward away from it.

    Another point is, with all the space north of the islands (Spitzbergen, Franz Joseph, etc.) it is obvious the flow of ice toward the Fram is not significantly large compared to other years when the flow was heavier. part of the issue is also related to the time of the season. Earlier it was easier to track, but as summer wore on, the ice seemed to lose its form much more quickly. I think it is simply melting sooner. However, the flow out of the Fram seemed to move much more consistently and quickly before the pause we had in July. Perhaps it is picking up again, but it doesn’t seem so.

    However, there was and is significant disintegration of the ice at the northeast corner of Greenland which is probably at least partly what was flowing out of the Fram before.

    As for the direction of flow overall, let’s do keep in mind the obvious: the gyre and the current that skirts Russia are part of the reason the ice piles up north of Canada and Greenland and not Siberia. it is obvious – and you can check the buoy movements to confirm, that the primary flow of ice should be from the Siberian side, and is, unless the winds are enough to overcome the currents (which they often are.)

    The buoys along the Canadian and US coasts have been moving with the gyre clockwise, so towards the Bering Strait, essentially, while those that were originally at or near that general location are moving either toward Siberia or down into the main pack.

    All this indicates to me the winds are not much overcoming the water movement, although the cyclonic activity has often seemed to be supporting this movement.

    That said, the ice spread along the entire western end of the basin indicates winds have either been neutral or supportive of a western/eastern flow. Given the gyre and the primary flow in from the Pacific, the ice would be expected to be hugging the Siberian coast a bit more, but it isn’t, it’s just spreading out. or, just melting where it is. Both, in my opinion. Essentially, there is no really strong bias to the wind and everything seems to largely be moving about as basic dynamics would lead us to expect.

    UPDATES at http://aperfectstormcometh.blogspot.com/

    Comment by ccpo — 14 Aug 2011 @ 3:09 AM

  298. dhogaza @ 294, I’m sorry that you misunderstood a comment of mine earlier in this thread. Or didn’t appreciate my #282.
    (recall 278 -270 – 280 – 281 282 285 286 289)

    You inform me “Nope, as I’ve said several times, a considerable quantity of ice has been blown out of the Fram Straight into the Greenland Sea,….” Yes, I have followed the melt and the changes in ice extent and more this summer. That you misunderstood me earlier is a separate fact. If you somehow read into my comments a claim that an unquantified “considerable” quantity was not blown through, please check and discover no such statement by me.

    Comment by Pete Dunkelberg — 15 Aug 2011 @ 7:55 AM

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