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@ Al Rodger, Dammit, you've got me started. Here are some more snippets... From the 1st January 2000, the Cryosphere Today Arctic Sea Ice Area shows approximately 95.1% of the days with a -ve anomaly. The last time there was a +ve anomaly with the CT Arctic Area was (if my sums are right) on the 11th December 2004. That single day was the only excursion into +ve territory since 4th April 2003. In other words, one day in the last 8 and a half years. The year-to-date CT Arctic Area anomaly is 37,000 sq km below the 2007 equivalent as at day 279 - or the 6th Oct. The Area as at that date is about 500,000 sq km above its 2007 equivalent. However, 2007 started to refreeze big time in the second half of this month. It could go either way, but I think 2011 will end up with the second lowest annual average for Arctic Area. Moving on to CT Global Area, 76.3% of the time since 1st Jan 2000 has been in the negative anomaly zone. Since 1st Jan 2008 the figure rises to nearly 82%, since 2009 it's at 87% and is at 95% since the beginning of 2010. The record number of consecutive days with a -ve Global Area anomaly is currently 445 days, with the run ending around the 8th December 2007. As at day 278 (5th October) the present run stands at 414 days - easily the second longest run thus far. The anomaly as at this date is -1.666 million sq km, and should this remain in negative territory past the 5th November, that would constitute a new record sequence. The Global Area anomaly as at this date in 2007 was 7,000 sq km lower than at present, but the year to date figure for 2011 is about 182,000 sq km lower than for 2007. Therefore, as long as the average anomaly for the remaining 87 days is less than +582,000 sq km (a very serious swing away from the present numbers) then 2011 will end up with the lowest annual average for Global Sea Ice Area. In terms of a rolling 365-day average of the CT Global Area, 2011 has already clocked up the 6 lowest figures on record. These occurred between the 14th to 19th September. Out of the 100 lowest rolling 365-day averages, 49 were in 2007 with the rest occurring this year. As the first of these 51/100 only happened 51 days ago, and the latest is at position 36, it is highly probable that 2011 will accrue further entries in the top (bottom?) 100. The distribution across the 100 lowest rolling 365's is also skewed. 2011 has 7 in the lowest 10, while 2007 has 7 in the 91-100 range. Who knows what the split will be by the end of the year? I'm sure I'm not the only one who finds these numbers rather scary. Cheers Bill F
Toggle Commented Oct 9, 2011 on October 2011 Open Thread at Arctic Sea Ice
@ Al Rodger I'd like to make a quick correction to the very first post on this thread. (I've been painting garden furniture for a few days - hence I've only seen this today!) The all time rolling 12 month low (thus far) was from November 2006 - October 2007, and not May '06 - April '07 as suggested. I had pointed out a few weeks back that October 2007 had had a huge impact upon the yearly averages, and I could not understand how this wouldn't feature in the lowest rolling-12. As Al rightly points out, the NSIDC figure for October could well produce a new record low - the magic number to look for next month will be 7.5 million sq km. Anything below that, and it's a new rolling-12 month low. That equates to 190,000 sq km less than October 2010, with the September average for this year already 290,000 sq km down on last year. The JAXA figures (if/when they start again) are less likely to produce a record. They would need to average about 670,000 sq km below last year, but were standing only about 550,000 down when the system went tits-up.
Toggle Commented Oct 9, 2011 on October 2011 Open Thread at Arctic Sea Ice
Nice one Mr Hamilton. In your first graph, the intriguingly numbered Fig 4, did you consider incorporating any of the other relevant measures, such as IJIS Area, Nansen Extent & Area or the DMI 30%? I know it could get messy, but it would be interesting to see if any discrepancies between these look to be systemic, eg seasonal. Of course, this would be harder to detect with the DMI 30% extent, but it should always be between the 15%s and the area. By coincidence, I had cause earlier today to raise the subject of ice loss at different times of the year. A poster on Tamino's Open Mind blog had recently "recommended" an article about Arctic Sea Ice over on the dark side (aka WUWT). Some of you may know of the original poster on said article, namely David Middleton. At present I can't get a handle on formulating a suitable response to the OP - the writing was so woolly that I'm still trying to figure out how he reached the inevitable conclusion that nothing out of the ordinary is happening. (What a surprise, especially from a "geo-scientist from the evil oil & gas industry" - his words, not mine, I hasten to add.) However, one misguided soul was gushing forth how the refreeze in winter was being ignored, and that talking about the September minimum was blatant cherry picking. It felt almost heartless to point out that (from the NSIDC data) the monthly trends in thousands of sq kilometres per annum were as follows... Jan -49; Feb -46; Mar -43; Apr -39; May -33; Jun -44; Jul -68; Aug -72; Sep -85*; Oct -57; Nov -53; Dec -47 * As I did not have the Sep 2011 figure available at the time, I actually stated that the September decline was currently -81 thousand sq km/year, but would rise to about 84 - I underestimated it.
RE: Logicman Two days ago, Logicman posted a link to an article on the Guardian website. The subject matter was ice loss in general, and was written by Damien Carrington. I wasn't particularly impressed by Carrington's understanding of the topic, and, consequently he rather left himself open to attack. However, I think Logicman's point was to read the comments - these were frankly astonishing. I often go on the Telegraph or Daily Mail blogs to play with the natives, but this was something else. If it wasn't for the fact that these people actually get to vote it would be bloody hilarious. The line that seemed particularly germane to this site was..."The only large place on Earth that is currently warmer than it was 30 years ago is the Arctic." I seriously doubt if some of these people could find their own backside using both hands. Cheers Bill F PS well done Neven
Toggle Commented Sep 28, 2011 on SIE 2011 update 21: post mortem at Arctic Sea Ice
RE: Chris Biscan Chris has just posted a link to the work of an oceanographer - Victoria Hill - studying the mechanics of rapid ice loss. This implicates algal growth within the ice as a factor, with alteration to the albedo leading to increased absorption of solar energy. This article isn't really stating anything new, but what interests me is how this might get spun in the deniosphere. Last year, a certain gentleman wrote a piece on his blog derived from an article published in Nature Geoscience. The original article related to modelled behaviour of soil microbiota, and our Anthony characterised this as "destroying a favourite AGW positive forcing theory". (I learned of this blog piece when it was parroted virtually verbatim in our local magazine.) As I freely admit to knowing diddly-squat about microbial behaviour, I had a quick look in AR4 to see what, if any, views the IPCC had to express on the subject. Section 7.3.3 of WG1 AR4 begins with the words… ” The net exchange of carbon between the terrestrial biosphere and the atmosphere is the difference between carbon uptake by photosynthesis and release by plant respiration, soil respiration and disturbance processes (fire, windthrow, insect attack and herbivory in unmanaged systems, together with deforestation, afforestation, land management and harvest in managed systems). Over at least the last 30 years, the net result of all these processes has been uptake of atmospheric CO2 by terrestrial ecosystems (Table 7.1, ‘land-atmosphere flux’ row). It is critical to understand the reasons for this uptake and its likely future course. Will uptakes by the terrestrial biosphere grow or diminish with time, or even reverse so that the terrestrial biosphere becomes a net source of CO2 to the atmosphere?” That hardly sounds like the description of some pivotal positive forcing cornerstone to me! It will be interesting to see if history repeats itself yet again, and if we'll start getting opinion pieces claiming that it ain't CO2, it's algae. (Sorry if that was a bit OT.) Cheers Bill F
Toggle Commented Sep 14, 2011 on The fat lady's singing at Arctic Sea Ice
RE: Paul Klemencic & NSIDC responses. Just to reinforce Paul's words, over the last 6 months or so, I have dealt with 3 people at the NSIDC on a variety of queries I raised. Without fail, the response was rapid and effective. Unsurprisingly - given the invective liberally expressed on certain sites - the people there get subjected to some pretty abusive stuff. However, despite the fact I was pointing out some errors on the NSIDC site, they remained polite and friendly. Kudos to them.
Toggle Commented Sep 14, 2011 on The fat lady's singing at Arctic Sea Ice
Seke Rob - thanks for the link. Regarding Arctic fantasies from the Ostrich tribe, I think the best one (but there are many candidates) I have heard concerned the North West Passage. One of these so-called sceptics decided to harangue me down the pub a few months ago with the interesting claim that the NWP had first been navigated in the 15th Century by the English explorer/adventurer Martin Frobisher. In return, I pointed out that this would be extremely interesting news to at least four entirely disparate groups of people. The first surprised group would of course be the entire population of Norway (and possibly all of the Scandinavian peoples) who would have learned at primary school about Roald Amundsen's epic 1903-06 journey of discovery in the Gjoa. The second group would contain everyone interested in Polar exploration. The third group would be those historians and/or biographers with an interest in the times of Queen Elisabeth I. Certainly some of these people would be aware than Frobisher had made three attempts at the NWP, and did manage to get a Bay named after him. (Even more famously, he had a character - Buck Frobisher, played by Leslie Nielsen - named after him in the series Due South.) However, the group of people most astonished by the claim that Frobisher traversed the NWP in the 15th Century has got to be the Theoretical Physicists. Why? Well, as he wasn't even born until the 16th Century (sometime about 1535 - there is some debate about the exact date) he must have had one hell of a ship in order to navigate the NWP during the previous Century. For people who like to style themselves as sceptics (or skeptics) little inconvenient tasks such as bothering to apply any sort of sanity filter just seems to be too much trouble.
Toggle Commented Sep 8, 2011 on New area record at Arctic Sea Ice
Seke Rob wrote..."Found a paper that actually debunks that story" Rob, I'm writing a piece for the local magazine debunking a whole plate-load of garbage - including the old "Arctic Ice was as low then as now" canard. Any link to extra ammunition is always welcome - although I think I'm already well into the overkill zone. Thanks Bill F
Toggle Commented Sep 8, 2011 on New area record at Arctic Sea Ice
RE: Comments from Seke Rob When I get someone from the Ostrich clan banging on about the Arctic loss (which simultaneously isn't happening, is recovering and is due to natural cycles) being balanced by gains in the Antarctic, I like to show them a 3-part graphic based on CT's Global Sea Ice Area chart. The first part runs from 1979-89, and anyone can see this spends most of the time above the X-axis , i.e. the zero anomaly line. The second part runs 1990-2000, and again, most people are prepared to admit that it is now just about even-Steven as regards time above/below the axis. The kicker is then showing 2001-onwards, where even the most bigoted viewer is hard pushed to admit anything other than the truth. Showing the 3 sections spliced together is then pure entertainment. For greater detail (if, say, somebody tries to argue the case for a seasonal pattern) I then use NSIDC's BIST tool to compare the hemispheres on a month-by-month basis. Also on the Global front, there was another mini record set a few days ago. (I posted this on an earlier thread, but I can't remember which one - sorry for repeating myself.) The first instance of a day with a combined anomaly greater than 2 million sq km was 2006, and we have had 80 so far. The count runs as follows... 2006 4 2007 24 2008 21 2010 6 2011 25 Out of the 55 that happened pre 2011, 39 (71%) happened mid September or later, so I would expect to see 2011's total of > 2 million sq km anomalies increase further.
Toggle Commented Sep 8, 2011 on New area record at Arctic Sea Ice
Hi Bob, As regards the "no tipping point" paper I mentioned, I do tend to agree with your assessment. My purpose in mentioning it was to further reinforce the lack of understanding as to the processes actually occurring in front of our eyes. On the other hand, the results of these process are pretty self-evident - worryingly so.
Oops, I didn't proof read my earlier post correctly. It's annoying when your fingers don't type what your brain is thinking. When I talked about ... a negative feedback mechanism linked to the increased oceanic heat loss out to the atmosphere (and hence eventually out to space) once the insulating layer of ice has gone bye-byes. (Think of igloos.) I was thinking of late in the melt season when the Ice-Albedo Effect is phasing out for the year. However, as just demonstrated, meaning to type something isn't the same as actually doing it. Sorry about the confusion - welcome to my world. The point I was trying - and failing - to make was that late melt-season radiative/convective loss to the atmosphere should act as a -ve feedback mechanism that would serve to postpone (for a limited period) the unwelcome prospect of a seasonally ice-free Arctic. There was a study conducted earlier this year (I'll try to find the link) which concluded that a "permanent" tipping point was unlikely. If I understood it correctly (always a big "if") the scientists in question thought that the Arctic could quickly - i.e. within a few years - return to the levels of a few decades back. However, I believe this was really dependent upon atmospheric compositions reverting to pre-industrial levels. (Not something I am ever expecting to see again.) Interestingly, on November 17th 2010, Rear Admiral David Titley, the chief Oceanographer of the US Navy saw fit to warn the House Committee on Science and Technology about the need to readdress naval readiness in the light of imminent (10 – 20 years hence) periods of effectively ice free conditions in the Arctic. It appears that the science community within the US Navy also has grave reservations about the accuracy of the claims pertaining to any supposed "recovery" of Arctic Sea Ice. Admiral Titley’s testimony to the House was a mere 8 pages in length, and was obviously tailored to be understandable even to those Representatives on the committee that were lacking a scientific background. Members of the public so taken in by the “less than scientifically robust” musings being spread on certain blogs could do far worse than to read Admiral Titley’s paper.
Hi there Neven, Bob, et al, May I make an observation about your comments about possible impediments to the flush out of Arctic Sea Ice once it gets below a certain threshold? My (albeit very limited) understanding is that there is a negative feedback mechanism linked to the increased oceanic heat loss out to the atmosphere (and hence eventually out to space) once the insulating layer of ice has gone bye-byes. (Think of igloos.) Obviously this would be working in direct competition with the Ice-Albedo Effect (due to both greater ocean surface exposure AND surface melt ponds) and with other +ve feedback mechanisms such as fracturing events leading to increased surface area in contact with relatively warm waters. It never fails to amaze me how much one hears nonsense in the deniosphere (and I'm sure Chris Biscan knows exactly where I'm talking about) about "positive feedbacks can't exist, otherwise we'd have a runaway greenhouse effect" (Even though there is no such thing as GHE, and even if there is - then it's very small, and even if it isn't - it's just natural cycles.) Apart from the normal chaotic behaviour, the system will be driven by a myriad of feedbacks (in both directions). I'm sure that time will reveal certain feedback processes that are currently not even recognised, or whose importance is currently grossly underestimated. After all, that's why modelled projections of Arctic Sea Ice behaviour from a few years back were so far out - the melt dynamics were simply not well-enough understood.
If one crunches some numbers from CT, it appears that another little milestone has been passed that further erodes the "Arctic Sea Ice is recovering" and the "Arctic loss balanced by Antarctic gain" nonsense. After importing the CT Global Sea Ice Area data, a filter was applied to pull out days that had an anomaly greater than 2 million sq km. Thus far, the entire dataset contains just 80 such occurrences in its 32+ year span. This first happened in 2006, and the subsequent frequency of such events was as follows... 2006 4 2007 24 2008 21 2010 6 2011 25 (thus far) Of the 55 that happened prior to this year, no fewer than 39 of these (71%) happened later in the year than mid September. That would certainly suggest there is a fair to middling chance that we might just see a few more >2 million sq km Global SIA anomalies this year. Looking at the year-to-date Global SIA average, this year is currently running about 16.92 million sq km, with 2007 at 17.01 Shifting focus to just the Arctic, I have yet to see a properly explained justification for the unwavering belief displayed on certain websites in this purported recovery of the Arctic ice. Partly, this seems to be fuelled by the frankly ludicrous "logic" that says... "The Arctic SIE minima reached a nadir in 2007: the fact that it is recovering is self-evident as the 2007 figure has not been breached for the last 4* years." (* NB One can insert any number of choice.) Unfortunately, if one chooses to look at something beyond a carefully selected fraction of the entire data set, the story is a bit different. Looking at the NSIDC Arctic SIE data set, the September average for 1979 was 7.2 million sq km. Taking that as the starting reference, there have (thus far) been 7 occasions upon which a new record low has been set. These were as follows... 1984 (0.4%) 1985 (3.3%) 1990 (10%) 1995 (1.8%) 2002 (2.2%) 2005 (6.5%) 2007 (22.8%) The number in parenthesis indicates how much was sliced off the previous minimum figure. The sheer size of the drop in 2007 should immediately scream "outlier" to anyone with even the most rudimentary grasp of time series data analysis. (Or even to anyone with an open mind.) Those of the ostrich persuasion seem to gain particular comfort from the fact that 2008 and 2009 "recovered" progressively from the 2007 nadir, as seen below... 2007 4.3 million sq km 2008 4.68 2009 5.36 2010 4.9 2011 4.?? However, there is an old adage about "those who don't learn from history are doomed to repeat its mistakes." As has been stated on these pages many times, things are changing up North, but a similar pattern to that above can been seen below... 1990 6.24 1991 6.55 1992 7.55 1993 6.5 1994 7.18 (look, it's definitely recovering) 1995 6.13 (Oops, how did that happened?) From the NSIDC figures, it can been seen that a new record low for September has been getting set about every 5 years. I am certainly not predicting that 2012 will be next, as it will depend on weather, not climate, when the record next falls. However, I most certainly would not bet against 2007 being comfortably eclipsed in either 2012 or 2013. (I can't see it happening this year, but who knows?)
@ Lord Soth 21:19 31st Aug Hi there LS, Just seen an exchange between Mr Watts and Julienne Stroeve over on WTF on this very topic. I'm afraid there was no real answer forthcoming.
Toggle Commented Aug 31, 2011 on SIE 2011 update 18: ten yard line at Arctic Sea Ice
@ Frivolousz21 and the foray over to WTF If anyone here has been on WTF, they may have noticed the thread pertaining to the final Arctic forecast poll. For those unaware of what this means, the Arctic Research Consortium of the United States (ARCUS) has put together a poll from an eclectic variety of sources, including the people over at WTF. The respondents are all invited to submit their estimate (guess?) for the mean September Arctic SIE. For the purposes of said poll, and to introduce a de facto standard into the proceedings, the figures to be used will be those produced by the NSIDC. Chris has mentioned it on this thread, and has pointed out that some of Mr Watts' fans are sticking with a September mean SIE that has already been undertaken by the 30th August Jaxa daily figure. Although this might seem absurd at first glance, I feel that, in the interests of openness, I should deliberately play Devil's Advocate. (Actually, I don't think one can do that by accident!) Looking at the Jaxa data, in 22.22 % of the occasions, the September average has ended up above the corresponding daily figure for the last day of August. (OK, that was spurious accuracy, it only happened twice - in 2002 & 2004.) Also, although the Jaxa September average was above its NSIDC equivalent in each of the last 4 years, for the 5 years between 2002 and 2006, the NSIDC figure was the higher of the two. Switching back to reality, although the Jaxa September means for 2002 & 2004 were higher than their 31st August equivalents, the difference was 50k sq km and 30k sq km respectively. Regarding the 5 years (2002 - 2006) during which NSIDC produced a higher September mean SIE than Jaxa, the average difference was 46k sq km. Over the most recent 4 years, this "trend" has reversed, and the Jaxa September mean SIE has averaged about 110k sq km higher than its NSIDC equivalent. In other words Chris, it's possible they could be right, but words like "straws" and "clutching" rather come to mind.
Toggle Commented Aug 31, 2011 on SIE 2011 update 18: ten yard line at Arctic Sea Ice
As recently mentioned on the End Zone thread, although this year trails the 2007 Jaxa SIE by 180,000 sq km, the year-to-date figures (up to and including 30th Aug) are the other way round. This year's y-t-d is currently 11.029 million sq km, with 2007 at 11.084. Obviously the gap between the 2007 and 2011 varies with the actual daily figures and the number of days these are being averaged over. At present, these two y-t-d figures are converging at a rate of about 1,000 sq km per day. What some may not have realised yet was the rather odd behaviour of the Arctic SIE during October 2007 when compared to (say) last year. At the end of September, 2010 was about 972,000 sq km behind, but had closed to 72,000 by the end of October. However, at around the 17th October, the difference had stretched to 1.4 million sq km. The effect this had on the yearly average should be pretty obvious. Therefore even if 2011 finishes comfortably behind 2007 in terms of the absolute minima, the annual average SIE figures are still very much up in the air.
Toggle Commented Aug 31, 2011 on SIE 2011 update 18: ten yard line at Arctic Sea Ice
Re: Dave Leaton Hi Dave, further to Seke Rob's earlier reply, if you look at Neven's Daily Graphs page, you will see 3 links giving the CT data for Arctic, Antarctic and Global Sea Ice. As I write this posting (using data up to Star Date 2011.6548 by CT reckoning) the current Global SIA is standing at (or should that be floating at?) 17.405 million sq km. The corresponding 2007 number was 18.019 Due to the phasing of the Arctic/Antarctic melt-freeze cycles, the Global SIA figure shows a very pronounced annual pattern of TROUGH, mini peak, mini trough, PEAK. This can therefore make the year-to-date figures seem a bit odd if not taken into consideration. However, the y-t-d figures (for yyyy.6548) are..... (drum roll, or egg-on-face roll for those who regard WTF as the font of all knowledge).... 2007 = 17.016 million sq km 2011 = 16.907 million sq km Global SIA is therefore lower this year than in 2007 using either current value or Y-t-d. However, this is a somewhat different situation from the present Sea Ice Extent in the Arctic. Using the Jaxa figures up until 30th Aug, the 2007 y-t-d extent is 11.084 million sq km with this year's figures somewhat lower at 11.029. (If I've got the database coding correct!!!) Pending today's Jaxa revision(s), 2011 will be around 200,000 sq km above 2007 - the next few days might be quite interesting - especially as the 2007 Jaxa figure only dropped about 36,000 sq km over the next four days! I've really no idea how the Arctic year-end Extent will pan out this year. Although September is obviously the time for the minimum, and everyone here knows about September 2007, it was actually the combined effect of September and October that enabled 2007 to make such ground in the annual average figures. Irrespective of how 2011 shapes up against 2007 in terms of the absolute minimum (or September average), the subsequent months will also play a very important role in determining which year ends with the lowest annual average. Me? I'm fence-sitting at present.
Toggle Commented Aug 31, 2011 on 2011 End Zone at Arctic Sea Ice
Just a quickie, as I hear some beer seductively calling my name... @ idunno >> FCAGW!?!! - Love it Thank you, we aim to please. A bit more "news" from July about the North Sea Route is that Rosatomflot (the Russian Ice Breaker fleet) has received approval from their government to purchase an additional 6 ice breakers. (3 atomic, 3 conventional) Its obvious that such an amount of capital outlay is not intended just for use around August each year - they are clearly expecting to be escorting commercial shipping for several (many?) months each year. Cheers Bill F
Toggle Commented Aug 27, 2011 on Oh, and BTW, the Passages are open at Arctic Sea Ice
I wasn't sure which thread to post this little snippet on, until, as if by magic, this one about the passages appeared. Just to reinforce Neven's comment about Suez size tanker's, have a little look at... As AGW (or CAGW, or FCAGW) is obviously a scam designed to facilitate a one-world, leftist, environmentalist, anti-free market government, it's nice to see that those poor energy companies are managing to make the best of things whilst they still can. (By the way, that ice isn't really melting - it's all down to badly positioned thermometers reacting to the Urban Heat Island Effect.)
Toggle Commented Aug 27, 2011 on Oh, and BTW, the Passages are open at Arctic Sea Ice
Oops, I accidentally hit the Post button too soon - see comment above. I had also meant to mention that 2011 is actually ahead of the pack at the moment when it comes to the Year-to-date (ytd) average Sea Ice Extent. Unsurprisingly, 2007 has the lowest whole year SIE average, but 2006 (not 2008) is next lowest. 2006 was actually lower than 2007 in the ytd stakes until (I think) the 24th August, after which date 2007 moved inexorably ahead. This year has spoiled the party somewhat by matching the 2006 ytd average on the 4th August, and is steadily pulling away. Obviously it is too early to say whether 2011 will end up finishing the year with a lower average than 2007; however, it will take an astonishing growth in sea ice in winter to prevent 2011 ending up with - at least - the second lowest annual average.
Hi Bob Wallace, Something you might find useful - I know I do - is the Browse Image Spreadsheet Tool (BIST) available on the NSIDC website. This is pretty flexible, and allows one to compare quite a variety of material. By way of an example, I tend to use this when dealing with the old "decline in the Arctic is matched by growth in the Antarctic" bollox. (I live in a village that is effectively twinned with Houston and Calgary when it comes to AGW denial,and that just about represents the peak intellectual standard of the "debate"!) If one column is set to show the Northern hemisphere, the next column set to show SH, and the number of rows is set to 12 (i.e. one per month) it tells a pretty convincing story to anyone with an open mind. Hope that is of some use.
Yesterday morning there was an interesting posting from Cynicus, which included the observation... On the one hand we have the resident commenters who seem to agree, day after day -for weeks already- that large portions of ice 'could melt out any time now' because all the signals seem to be there. On the other hand we have about two weeks of continuous very low extent decrease reports from IJIS, NSIDC etc. It looks like the local ice is simply not aware of it's (sic) total state and assumes that -because it resides in the Arctic- it will not melt, no matter all the visuals and model outputs we humans can produce. By way of response, I would start by pointing out that there were actually only 6 days of VERY low decrease (averaging <21k sq km/day). If one takes the JAXA average over the two week period from 20th July to 3rd August, the daily average was a somewhat higher 39.5k However, there is nothing surprising about this radical drop in the daily delta from the numbers being recorded earlier in July- it's caused by a little phenomenon known as weather. Now, how to put this in context? In 2010, between the 5th and 16th July, the daily average drop fell to 42.6k sq km. In 2009, starting from June 7th, it took 6 days to drop a mere 75k sq km. In 2008, between 20th May and 2nd June, the drop rate was a paltry 27.5k sq km/day. As most people here know, these 3 years went on to experience, respectively, the 3rd, 4th and 2nd lowest September extents thus far recorded. In other words, this kind of slow-up is hardly anything out of the ordinary. However, what WAS out of the ordinary was the behaviour during 2007. As I recently mentioned on Real Climate, 2007 had an 8 week spell averaging 91k sq km/day, with the lowest during this period being 48.5k. The two-week periods either side averaged about 45k/day between them, giving an average over the 12 weeks of a tad over 75k sq km/day. If 2007 had taken a hit like any of the subsequent years, we wouldn't be hearing quite so much bollox about "recovery" of the Arctic Sea Ice. For a bit more context, if the drop rate for the remaining 27 days of the month stays at the average experienced during the two week "hiatus" that caught your attention, August 2011 would STILL have the second lowest average extent thus far recorded.
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Aug 5, 2011