July ARCUS forecast poll – What will the September NSIDC Arctic minimum extent be?

Once again, I’m going to give WUWT readers an opportunity to make a forecast for submission, based on voting. See the poll at the end. 

I’ll run this poll each month in the week before the deadline, and we’ll see how we do as the minimum approaches. The value used by ARCUS is the NSIDC value as they say here:

The sea ice monthly extent for September 2010 was 4.9 million square kilometers, based on National Snow and Ice Data Center (NSIDC) estimates.

So don’t be using the JAXA graph to forecast minimums, though it it useful for determining short term trends as it is more responsive than the NSDIC graph below, which is averaged.

http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

Here’s the latest JAXA graph:

JAXA AMSR-E Sea Ice Extent -15% or greater – click to enlarge

On May 30th I submitted the results of the first poll to ARCUS to be included in their June Outlook, as shown below:

Figure 1. Distribution of individual Pan-Arctic Outlook values (June Report)

Download High Resolution Version of Figure 1.

WUWT is second highest, at 5.5 million sq km. Notably missing this year is “Wilson”, who in the last two years started out with impossibly low values such as 1 million sq km. I’ll repeat the poll next week in preparation for the July Outlook. In the meantime, check the WUWT Sea Ice Page for the latest.

Here’s the poll for the ARCUS July outlook, it will run until July 30th at noon EST.

92 thoughts on “July ARCUS forecast poll – What will the September NSIDC Arctic minimum extent be?

  1. More in Arctic Icebreaker/Shipping/Fishing/Cruise-Liner News:

    “Icebreaker for Shell’s oil-spill response fleet needs Inupiaq name – June 22nd, 2011″

    “The 360-foot-long, low-emission ship, under construction in Louisiana by Edison Chouest Offshore, is scheduled to launch late this summer. It will be ready for sea trials in January, said Capt. Michael Terminel, with Edison’s Alaska operations.

    It will join the icebreaker Nanuq to support Shell’s proposed exploration drilling in the Beaufort and Chukchi seas starting in summer 2012. One vessel will work in each sea, said Curtis Smith, Shell spokesman.”

    http://www.thearcticsounder.com/article/1125icebreaker_for_shells_oil-spill_response

    “A Push to Increase Icebreakers in the Arctic – August 16, 2008

    “In the meantime, a resurgent Russia has been busy expanding its fleet of large oceangoing icebreakers to around 14, launching a large conventional icebreaker in May and, last year, the world’s largest icebreaker, named 50 Years of Victory, the newest of its seven nuclear-powered, pole-hardy ships.”

    “Shipping traffic in the far north is not tracked precisely. But experts provided telling snapshots of maritime activity to legislators and other officials from Arctic countries at an international conference last week in Fairbanks, Alaska. For example, Mead Treadwell, who attended the conference and is an Alaskan businessman and the chairman of the research commission, said officials were told that more than 200 cruise ships circled Greenland in 2007, up from 27 in 2004.

    Lawson W. Brigham, chairman of the three-year Arctic Marine Shipping Assessment that is scheduled to finish work this year, told the gathering that more than 5,400 vessels of 100 tons or larger operated in Arctic waters in the summer of 2004. During that summer there were 102 trips in the Northwest Passage and five complete transits of that legendary route, he said.”

    http://www.nytimes.com/2008/08/17/world/europe/17arctic.html

  2. Can you change the “4.6 to 4.8 million km2″ range to 4.6-4.7 so its size is the same as the others in the middle?

    -Scott

  3. Thanks Anthony, I was the same as you last month. I have put it up by 0.1 this time to 5.1

  4. Anthony, Do you think it prudent to encourage people to wager on an “estimate” of a natural event, that is “smoothed” mathematically in the presentation? Surely that is a procedure that we sometimes disapprove when done by others. (Insert smiley).

  5. I think it is clear that the Arctic ice is in a bit of a decline extent wise. But I think it is equally clear the mass is almost at the decadal norm.

  6. Here’s the poll for the ARCUS July outlook, it will run until July 30th at noon EST.

    July or June?

  7. My guess is 4.6 to 4.7. (There is an error in the poll choices – it has 4.6 to4.8).

  8. It will “unexpectedly” flatten out at around 5.7 million.

    That’s my story and I’m sticking to it.

    Sorry to say I haven’t the time to join those who argue about what is happening on a day-by-day, play-by-play manner. I may drop by to lurk, and chuckle at some of the exchanges, but some of us have to work.

    See you in September.

  9. Psychic Larry predicts that the September NSIDC Arctic minimum extent will be the same as last year.

  10. I wonder … is this an attempt to test reliability of public polls in comparison with scientific forecasts?

  11. I’ve voted.
    The year? 2111, the time June, A Monday morning. Scientists all arouund the world are in a turmoil & in furious debate about what scientists in the late 20th & early 21st centuries were claiming to be an apparently ridiculous statement by some so called environmentalists that sea-ice was declining in the Arctic Circle at that time. Apparently the Arctic ice changes are repeating themselves almost in an identical manner! Archaic primitive computer models of the time had been shown 90 years ago to be totally inadequate & based on awfully flawed assumptions about how the Earth’s climate worked & how the variabilty of the Sun impacts upon it. One scientist, a Professor Hyram D. Donethesciece, of the world famous Anthony Watts University in California, said that the actual early satellite measurements did not show any particular abnormal changes or fluctuations in sea-ice extent, other than normal small changes over time in accordance with wind & sea current variations of the last 130 years, & in fact the small decline evidenced way back in 2007, ballyhooed at that time as a signpost for impending global doom, was almost indistnguishable from the average figure for a September minimum! A colleague, Professor Arthur P. Checkedhisfacts, went one stage further by saying that taking into account historical & annecdotal evidence way back to the 18th century, suggested that fluctuations in Arctic & Antarctic Sea Ice was a prefectly normal thing to see over time. He went on to say that too many poor scientists of the late 20th & early 21st centuries were too quick to jump to conclusions to secure their taxpayer grant funding because of their well intentioned but flawed political views! He also suggested that if they had paid more attention to what was going on elsewhere in the Solar System, they would have realised it was the Sun all along & could have saved millions of lives from the effects of disease & starvation that followed in the early 21st century:-)Sarc off.

    Apologies to any Professors Hyram D. Donethescience & Arthur P. Checkedhisfacts, if they exists, knowing my luck, they really do!!!!

  12. To all those believers of AGW that wish the Arctic to melt to prove a point, not a good idea. Those against AGW wish the Arctic ice to grow to prove their point. My problem is that my best guess is that a melting Arctic sea ice is our wonderful world dumping heat and thus cooling. The melting of ice tends to suck a lot of heat from the ocean. That heat escapes toward our north star never to return. Turn on an airconditioner and you have to wait sometime for it to kick in. The Earth responds not in minutes hours or days but in years. The sun had a few frenzied peaks and that heat is now being dumped. The sun is now on holidays and the dumping still continues with the inertia in the system. Very soon the new catch cry will be Anthropologic Global Cooling, it will still be our fault and caused by CO2.

  13. Since there’s no el Nino warmth hanging about in the Northern Hemisphere I’ll say in the vicinity of 2009, just a tick higher than it.

  14. I used a more sophisticated method of calculating the minimum sea ice for this year. I used a straight edge to line up with edge of the graph, instead of eye balling it.
    I notice that my guess is so far also the most popular guess.

  15. I’m upping my vote to “greater than 5.5″ because, despite the continuing loss around the periphery, I think the base limit will have been raised by longer staying thick ice. I’m reckoning on the final graph to show a wider though shallower curve after mid July.

  16. I have nothing but my intuition to explain my forecast for Arctic minimum this September. I am going to go with 5.5-5.6. I am thinking we are seeing a flattening of the “sign wave” pattern of waxing and waning ice. Mind you, once the “big push” of climate propaganda takes off this summer I would not be surprised if NSIDC claims the ice completely melted for the first time ever. The Arctic is where they will make their last stand. It’s the only place left where they can make outrageous claims of warming because nobody ever goes there except them.

  17. Any ice you see is an illusion created by big oil and the evil polluters! The more snow you see, the more you can be sure of the denialist agenda! /sarc

  18. mark h says @ June 27, 2011 at 1:11 am “I dont know if you guys have seen this already but I,ll put the link here anyway.Venus no greenhouse effect.”

    Oh, and Venus has the same atmospheric conditions – including pressure – that we do I take it? Everything behaves the exact same way as here? Uh, no.

  19. I fail to see why arctic ice extent is such a big deal. Arctic sea ice extent is almost exactly analogous to the thermostat in a water-cooled automobile engine. As there is more heat to dispose of the thermostat opens up wider allowing more water flow into the radiator. As there is more heat to dispose of from the tropics arctic sea ice extent shrinks which exposes more liquid water surface. A liquid water surface gives up heat FAR faster than a frozen surface.

    We know global average temperature has been rising. We got 30 years of satellite data to prove that. But it isn’t getting warmer in the tropics. The “radiator” at the north pole starts working more effectively by opening up more liquid water surface and just dumps that extra heat out the path of least resistance – straight up into space. As a result the pole gets warmer but the effect diminishes as you move south. The ironic part of all this is we’re in a damn ice age and we really some extra warmth in the higher latitudes to extend growing seasons. Increasing CO2 is a huge net benefit to life on this planet including us.

  20. 4.9 – 5.0

    This year could be higher slightly depending on late summer weather as always (or lower even) but in this case weather patterns appear to be set in this range at least in my mind.

  21. Sun continues to petter out today 26 SSN

    http://www.solarham.com/

    At this rate one wonders whether average max might be 40 SSN. Im guessing that the effects of the dying sun are beginning to kick in with SST staying well below previous years despite a slight El NIno and of course TLT following this already. I reckonthis yars average temp will be aroung 0.1 to 0.2C (+) based on the AMSU averag for 30 years.

  22. @Glenn says:
    June 27, 2011 at 1:04 am

    “wow, that’s a nice bell-curve ”

    Bell Curve? Where? All I see is a running time series plot of the actual Ice extent.

  23. Going with ±5.1; flipping the coin and going to the plus side 5.1-5.2.

    I assume you meant to say the poll will run to June 30th vice July.

  24. The AO has calmed to neutral and appears stuck there. Looking at ice transport maps, I don’t see much chance of a wind-driven flush. The ice is also pretty thick and concentrated tightly, so it would need a good wind to shove it out. So I will peg it above 5 somewhere.

  25. Curious if the use of ice breakers help the prevailing winds reduce the ice coverage???

  26. Will the winds blow as in ’07? Maria knows but kim doesn’t. Despite those unusual winds, the recovery of ’08-’10 suggests that the turning point has been reached in a cooling world.
    ===========

  27. I’m sticking with the Canadians at 5.0 M Km2. However, the age of the remaining ice continues to increase, so the long-term recovery of the ice cap appears to be ongoing.

    Now, keep the damn icebreakers out of there and give the thing some time to recover!

  28. @Moderate Republican,

    “Oh, and Venus has the same atmospheric conditions – including pressure – that we do I take it? Everything behaves the exact same way as here? Uh, no.

    Nice attempt at a drive by. The ENTIRE article is about temperatures at equal pressures.

    Amazing you learned to type without learning to read.

  29. Under 4.5…a guess…but in watching “paint dry” all winter and spring it appeared that the freeze up was late in many areas, especially Hudson Bay, and that the thaw is early. Until very recently, 2011 looked ahead of 2007 in many areas, and still is in some, like north of Russia, though things are changing relatively quickly now.

    Anthony, why don’t you add a map of the Arctic that indicates all the various sea names on your Sea Ice Page? It would be a handy reference.

  30. Gary Krause says: June 27, 2011 at 8:18 am

    Curious if the use of ice breakers help the prevailing winds reduce the ice coverage???

    I think the answer is definitely yes, it’s just a question of magnitude. Icebreakers are designed to help reduce ice coverage, and icebreaker captains are generally smart enough not to break ice when the wind is blowing towards the icepack, lest their icebreaker get stuck. If you look at the US Coast Guard Icebreaker Healy’s Cruisetracks for 2006;

    http://www.icefloe.net/images/HLY-06annot.pdf

    2007;

    http://www.icefloe.net/docs/HLY-07track.pdf

    and 2008;

    http://www.icefloe.net/docs/healy2008.pdf

    it seems intuitive that icebreakers, in conjunction with wind to blow the broken up ice into warmer waters, would help to reduce sea ice coverage.

    Unfortunately, we cannot see what the Icebreaker Healy was up to in 2010, as the Cruisetrack is missing;

    http://www.icefloe.net/healy-2010-cruise-reports

    and it is harder to see the current year, because for some reason the US Coast Guard Icebreaker Science Operation site has added a login to their Realtime Tracking Map:

    http://www.icefloe.net/healy-realtime-track-map

    Site registration is here:

    http://www.icefloe.net/user/register

  31. I went for less than 4.5 because we’re lower than 2007 earlier. However, I haven’t a clue and made a guess in the spirit of counting beans in a large jar. We’ll see how I do.

    In the meantime, I’m puzzled. There seems to be a large disconnect between the Arctic and North America at latitude 40 degrees here in Utah. We have had a cold, very long spring. Vegetables that are normally planted here in April are being planted now. If it is so cold and wet here, why isn’t it even colder up there? It is clear I don’t know how the Arctic works. So any help would be welcomed. I figure the La Nina has something to do with it, but I figured it would have made the Arctic cooler too with much more ice extent than is currently showing. I hate making even a guess prediction in line with the Arctic doomsayers. I won’t take any pleasure if I’m right.

  32. Dave Springer @ 7:17
    says “We know global average temperature has been rising. We got 30 years of satellite data to prove that.”

    We do? Check the graph in the link below. I count 13 times that the curve has crossed the zero line. This if for the “global lower atmosphere” that comes from satellite data that you mention. This is a “running, centered 13-month average” – the latest month shown being +.13 C. degrees. I’m hard pressed to claim a warming trend with this data.

    Now if you want to take surface station data and torture it, in-fill, back-fill, project land stations out over the ocean and the Arctic ice – well then, maybe if you squint you can see warming, dying polar bears, and some even claim to see CO2. Not me.

  33. @ John Hultquist: respectfully, I think the warming trend in Dr Spencer’s chart is very clear, just from eyeballing the chart.

    It’s not the number of times the running average (red) line crosses the horizontal T = 0 axis that’s important. The mid-point of the graph is in 1995: before then all red points are in the lower (T 0) of the chart apart from 3 fairly brief excursions below the line, so the mean is about plus 0.1C. This shows a clear warming trend over the 32 years plotted.

    I thought Dave Springer’s thermostat concept must be essentially correct – but this must be largely a NP phenomenon, for while the arctic basin could be completely ice-free at onset of winter, in the Antarctic that would be impossible anywhere over 75 degrees S, due to the land-based ice sheet.

  34. http://www.sciencedaily.com/releases/2011/06/110626145250.htm

    Prodigal Plankton Species Makes First Known Migration from Pacific to Atlantic Via Pole

    ScienceDaily (June 26, 2011) — Microscopic plant disappeared from North Atlantic 800,000 years ago; unwanted return 1 of several climate change symptoms already apparent throughout European oceans Some 800,000 years ago — about the time early human tribes were learning to make fire — a tiny species of plankton called Neodenticula seminae went extinct in the North Atlantic.

    Today, that microscopic plant has become an Atlantic resident again, having drifted from the Pacific through the Arctic Ocean thanks to dramatically reduced polar ice, scientists report.

    The melting Arctic has opened a Northwest Passage across the Pole for the tiny algae. And while it’s a food source, it isn’t being welcomed back by experts, who say any changes at the base of the marine food web could, like an earthquake, shake or even topple the pillars of existing Atlantic ocean life.

  35. I don’t see the point of guessing the future ….. Besides, we already have government funded organisations to do theis …. NASA, NOAA and THE MET ORIFICE

  36. It will be interesting to see where WUWT comes in.

    You have 1 more month of information
    Last months vote here is what we knew

    May 4 extent/minimum
    2011: 14.15 million square kilometers
    2010 14.69 million square kilometers/4.60 million square kilometers
    2009 14.58 million square/ min 5.10 million square kilometers
    2008 14.49 million square /4.52 million square kilometers

    The prediction was 5.5
    Now here is what we know, june 6 extent/minimum
    2011: 12.79 million square kilometers
    2010: 13.10 million square kilometers/4.60 million square kilometers
    2009:13.39 million square:/ min 5.10 million square kilometers
    2008:13.18 million square/4.52 million square kilometers

    Guessing 5.5 in light of the extent and last months melt rate, would seem to
    fly in the face of “observations.” looks to be like 2008.
    4.5

    Here is a good test. All the other forecasters (models, heuristics, stats) will take
    the last months observations into account, to modify there forecasts.
    Will they generally go up? go down? or stay the same.
    It will be interesting to watch who modifies their view based on observation
    and by how much.

    of course this is a poll, but nothing prevents people taking the poll from considering
    observations. The ice varies “naturally”. if this years “natural” is like previous years
    “natural” what does one expect? Looks to me like people here want to believe that
    the ice melt will, for some strange reason, be less in the months of june,july, aug, sept
    than in previous years. What observation supports such a belief?

  37. steven mosher says:
    June 27, 2011 at 12:35 pm

    Steve, it is my opinion that many of the people who voted 5.5 million km^2 don’t follow the numbers much at all. I would rather have seen the mean value of the poll submitted rather than the mode. IIRC, the second-most common poll value was ~5.0 million, which is much more reasonable.

    Several of us here do follow the ice closely with our own spreadsheets incorporating the common datasets…and we likely voted somewhere in the upper 4.x million range. I hadn’t fired up my spreadsheet for this melt season yet, but I think I voted somewhere in that range based on my experience last year (I put my guess in the comments from last month, so I could check there). I fired up the spreadsheet last weekend, so I’ll do some analyses and put together my updated estimate based on them…though I doubt it’ll be that different from my experienced estimate last month.

    All that said, there may some well-educated people here that are guessing well over 5 million based upon the belief that the ice in the Arctic Basin has been getting older/thicker the last few years…a belief that is semi-supported by PIPS (which at least had respectable agreement with Cryosate in Jan/Feb).

    -Scott

  38. Apparently, essentially, when ever the arctic suffers in width in takes on in thickness at the same time when antarctica adds on and some mountain steals the rest of the glory.

    And that’s what the freaky climate communist hippie is afraid of, the pre-order for CAGW disaster due to CO2, which just makes them look the more crazier for not minding the several thousands of ships breaking up the ice in the arctic every year. The ice doesn’t care about whether it is an oil prospector with its newest biggest ice breaker in the vanguard or some truly amazing crazed climate communist hippie trying to reach the north pole by “canoe-ice-breakers” or better yet with green peace tourist, err science, trips.

  39. Scott,

    Ya I used to do a statistical analysis of it. err I think I won the first ice bet at Lucia’s.. (yup I did, but not by using stats.)

    I think the interesting thing is how few people use the information they have to inform and reform their beliefs. I will say this. I suspect there will be a tendency for people to avoid changing their beliefs month to month, and that the 5.5 will get a good number of votes, even when it becomes clear that 5.5 is a hope more than a warranted belief.

  40. Steven, playing the numbers game is wriggle matching. Rather unscientific in my opinion. I’ld rather keep tract of weather pattern variations that are predictive of ice loss/ice retention, in other words, the mechanics of ice loss. Don’t care much for the numbers. There are no mechanics in just looking at trends and numbers.

  41. Let’s see, the entire state of Alaska is somewhere around 1.7 M sq.km. The Arctic ice minimum will be around 2.5X-3X the size of Alaska this year. If the minimum icecap steadily decreased each year by an area the size of New Jersey (~22.5 K sq.km.), then in 200 years the Arctic will be ice free.
    Whoopee.

  42. I have been looking at the sea ice reference page every day since I discovered it, well over a year now, and I have read many articles discussing the sea ice extent and its changes.
    I have learned that what you see in the graph plotting the extent at this time of year is not predictable, or indicative of what the final September ice extent minimum will end up as.
    The lower extent we have been observing this year is largely affected by a small amount of warmer temps seen along the atlantic coast in the Greenland, canadian area, amongst other things.
    Some areas, such as hudsons bay, once covered in ice, no longer can contribute to sea ice extent as it is land locked.
    Some areas it doesn’t matter when the ice has melted as a reset takes place once the dark returns again, similar to how my local mountains always lose their winter snows at some point in the summer, and no matter when that has occurred, the first winter snows return is not affected.
    Ice thickness has a affect on extent, and during this time of year, because of the nature of the beast, geographical in nature, doesn’t show well in the graphs, and will make its effect appear later in the year in a possible slowing of the rate of extent loss.
    Wind will also have an effect, and its direction especially so. There are also aspects of an ice factory, were ice can be created in one cold spot and continuously be blown out into warmer waters, having some effect.
    Note this is just a quick review of some of the intuitive knowledge I have gained over the past year and a halve of daily research on the subject, and I am leaving out many other observations.

  43. Gary, good on ya. A study of the mechanics of ice movement via wind, in situ melt, and atmospheric/oceanic conditions is where the money shot is.

  44. “Steven, playing the numbers game is wriggle matching. Rather unscientific in my opinion. I’ld rather keep tract of weather pattern variations that are predictive of ice loss/ice retention, in other words, the mechanics of ice loss. Don’t care much for the numbers. There are no mechanics in just looking at trends and numbers.”

    No wiggle matching is something entirely different. Between now and the the minimum of course several mechanical factors will dominate: wind, currents, temperature, sea ice thickness.

    Doing a statistical forecast is equivalent to saying ” the mechanical factors we will see in the future will be like those we have seen in the past” of course, that approach will be less accurate the more the future diverges from the average of the past, so one might want to add other factors.
    Like forecasts for the mechanical aspects at play.

    Your vote is for above 5.5. Based on what numerical approach. You see if you document an approach, then we can see what went wrong with it and we can improve it. So, showtime!

  45. Pamela Gray says:
    June 27, 2011 at 4:59 pm
    Steven, playing the numbers game is wriggle matching. Rather unscientific in my opinion. I’ld rather keep tract of weather pattern variations that are predictive of ice loss/ice retention, in other words, the mechanics of ice loss. Don’t care much for the numbers. There are no mechanics in just looking at trends and numbers.

    ==============

    Repeated for effect. Excellent.

    Chris
    Norfolk, VA, USA

  46. your selection is too much? if want see real result you should put max 5 choice only

  47. Gary Mount said

    “The lower extent we have been observing this year is largely affected by a small amount of warmer temps seen along the atlantic coast in the Greenland, canadian area, amongst other things.”
    “Some areas, such as hudsons bay, once covered in ice, no longer can contribute to sea ice extent as it is land locked.”

    Gary, the main areas losing ice up to now are Barents, Kara and Hudson Bay, most seems to have gone on the Russian side. Also, Hudsons Bay is not landlocked.

    I agree with Steve Mosher, I’m sure a lot of people voting on here only have a passing interest on this part of the site’s postings and “want” it to be high. This coupled with the fact the 5.5+ choice is 5 times bigger in range than the common 5.1-5.2 etc etc means it screwed the voting too high last time. I agree with Scott, it should be the mean.

    Andy

  48. Tim Channon says:
    June 27, 2011 at 8:02 pm

    Silly question: Which actual dataset(s) are they talking about?

    Tim, this link has most of what you could ask for. It’s loaded with plots, but the real substance comes in the links to downloaded data. :-) It’s not much effort to get it into a spreadsheet and start analyzing trends yourself.

    http://wattsupwiththat.com/reference-pages/sea-ice-page/

    -Scott

  49. well sharks you have two approachs. Pam says above 5.5 and refuses to disclose her method. except to say “its mechanics” and “science”. Me? I say 4.5. Method? easy. its 2008, assuming the mechanics are the same as then ( big assumption) it’ll be closer to 4.5 than it is to ABOVE 5.5.

    Funny how you like secret methods with no methods and no maths to check

  50. By the way, with La Nina barely hanging on but for ENSO neutral and La Nina returning forcasts, the chance is greater for a negative AO, meaning weaker polar winds. So I stand by my +5.5 prediction. We are not set up for a strong wind pushing ice around and down through Fram strait. The day to day ice movement grid also shows very weak ice movement up there. If the polar vortex picks up, then I will be wrong by a long shot.

  51. Lowesssssssst everrrrrrrrrr! (A mere signpost on the way to the end of the interglacial)

  52. I get confused about the AO and polar vortex. If it is a negative AO and low polar vortex in Winter then this leads to less ice, however if it is a negative AO and low polar vortex in summer then less storms result at higher lattitudes so more melt in situe ( even if the winds are less).

    Hence, by my reasoning ( which I admit may be screwy) a negative AO will not hinder ice loss

  53. TimC says:
    June 27, 2011 at 11:58 am

    “I thought Dave Springer’s thermostat concept must be essentially correct – but this must be largely a NP phenomenon, for while the arctic basin could be completely ice-free at onset of winter, in the Antarctic that would be impossible anywhere over 75 degrees S, due to the land-based ice sheet.”

    Largely, yes. There’s some variability in SH sea ice but the sweet spot where ocean heat content can escape is blocked by a continent. Arrangement of the continents has a lot to do with climate. The current arrangement is evidently favorable for an ice age.

  54. John F. Hultquist says:
    June 27, 2011 at 10:03 am
    Dave Springer @ 7:17
    says “We know global average temperature has been rising. We got 30 years of satellite data to prove that.”

    “We do? Check the graph in the link below.”

    Yes, we do. The trend is upward. It’s mostly below the zero line in the first half of the record and mostly above it in the second half. If you can’t eyeball that you might want to get your eyes examined.

  55. RobbCab says:
    June 27, 2011 at 9:12 am

    “Nice attempt at a drive by. The ENTIRE article is about temperatures at equal pressures.”

    Venus is a red herring. No sunlight penetrates to the surface. It’s hot enough to melt lead on the surface because, unlike the earth, once the internal heat of the planet reaches the top of the crust it can’t radiate out into space but must continue to make its way slowly through an atmosphere 80 times denser than the earth’s. Internal heat has virtually no effect on surface temperature on our planet. Only a few milliwatts per square meter comes from below because the crustal rocks are very good insulators and it can readily escape once it reaches the end of the rocks while at the same time a couple hundred watts per square meter reaches the top of the rocks from the sun. On Venus no heat from the sun reaches the crust as it is all blocked by the atmosphere while the internal heat of the planet can’t escape easily until it reaches clear sky. So the internal heat of the planet builds up quite high in the lower atmosphere.

    None of this stuff should be called the greenhouse effect. It’s much more apt to call it the insulation effect. Venus has a great deal of insulation its atmosphere which masses 80 times greater than the earth’s. It insulates the surface from solar heating in the upper atmosphere and insulates the surface against internal heat loss to space.

    A very ignorant assertion is made about Venus in that the surface temperature is a result of Boyle’s Law i.e. gasses undergoing compression heat up and those undergoing expansion cool down. The ignorant part is conflating compression with pressure. The surface pressure of the Venusion atmosphere is static. The only way it could experience any compressional heating is if the pressure were constantly increasing i.e. undergoing compression. Once the compression stops and pressure becomes static Boyle’s Law no longer applies.

  56. So it looks like my spreadsheet doesn’t mean too much on June 30. Correlations are very poor, especially in the last decade. Consequently, I’m taking the same approach as Steve Mosher, but I’m using 2010 as my proxy instead of 2008. I’ll assume equal loss wrt to 2010 in the coming months.

    The average for June 1-29 for 2011 is 53000 km^2 higher than 2010. From that, I’m guessing we’ll end that much higher, so my guess is 4.95 million km^2, smack dab in the middle of 4.9-5.0 million. Note that this should make Mosher happy, because it’s slightly different than my guess of 4.8-4.9 million last month. ;-) I put in my vote about 12:04 EST, so hopefully it counts. On the bright side, it looks like the 5.0-5.1 vote is going to win this month, which is much more reasonable than last month (a lot fewer total votes this month, so maybe fewer passers-by than last time?)

    We should learn a lot in July. Correlation approaches that are nearly worthless now are quite telling by July 31. This will be an interesting year I believe. Last year fell in the this odd middle ground where everyone tried to claim victory. If PIOMAS is right, we almost have to see a smaller extent this year than last year (especially considering that CAGWers claimed that last year’s weather was ideal for keeping ice). If PIPS is right, we almost have to see a larger extent this year than last year (especially considering that CAGWers claimed that last year’s weather was bad for keeping ice).

    -Scott

  57. Good thinking there Scott and nice analysis.

    Daily rate of ice loss is at the higher end of the spectrum currently so sub 5 million is still well on the cards.

    Andy

  58. AndyW says:
    July 3, 2011 at 10:04 am

    The analysis is very simple, but probably as reasonable as any other unless one gets heavily involved with estimated thicknesses, SSTs, projected weather patterns, etc.

    Sub 5 is definitely on the cards and probably more likely than > 5. I would argue that sub 4 might even still be in the cards (it would take a 2007-type loss…well, slightly worse than that).

    -Scott

  59. Hi Scott,

    Just had a quick look at previous years on which day of the year extent went below 8×10^6km2 in conjunction with final extent :-

    2002 27 July => 5.6 final
    2003 28 July => 6.0
    2004 31 July => 5.8
    2005 20 July => 5.3
    2006 18 July => 5.8 ( very slow August)
    2007 13 July => 4.3
    2008 21 July => 4.7
    2009 20 July => 5.2
    2010 17 July => 4.8

    2011 is currently on track to hit sub 8 from 12th to 16th July so even if it is a very slow August like 2006 then it puts an upper limit of about 5.5 on things for final extent. More likely to be be closer to 2007. Currently I am thinking 4.5 to 4.6. My original estimate from very early in the year was about 4.75.

    Andy

  60. By the way, with La Nina barely hanging on but for ENSO neutral and La Nina returning forcasts, the chance is greater for a negative AO, meaning weaker polar winds. So I stand by my +5.5 prediction. We are not set up for a strong wind pushing ice around and down through Fram strait. The day to day ice movement grid also shows very weak ice movement up there. If the polar vortex picks up, then I will be wrong by a long shot.

    #################
    nice to make a high low bet.

    What’s the chances that the polar vortex picks up? and how far off will that make you.

  61. July 2010 was not very good for daily extent loss, not that many days over 100 000, I think 2 or 3 from memory, this year we have already had

    -149375
    -168125
    -75782
    -102968
    -81719
    -117969
    -149844

    2007 had about 10 or 11 ( again from memory)

    At this rate the time to reach sub 8 million square kilometres in extent will be the earliest in the short JAXA history

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