By Steve Goddard
Arctic Ice (red line above) has dropped just below my June forecast (dashed line.) Over the last two weeks, strong southerly winds reminiscent of 2007 have compacted and melted significant amounts of ice. The modified NSIDC image below shows ice loss over the last week, in red.
The break in the weather can be easily seen in the DMI temperature graph, as a sharp upwards spike two weeks ago.
The NCEP forecast calls for colder and calmer weather during the next two weeks, so ice loss should drop off quickly.
The DMI 30% concentration graph has already flattened, and is running even with 2009.
The modified NSIDC image below shows ice gain over 2007 in green, and loss in red.
PIOMAS continues to overestimate (red) ice loss by a substantial margin. Green shows areas where they underestimated ice loss.
It continues to look like my June forecast will be close to correct, though as we have seen – this contest is a crap shoot. It all depends on the wind.
Julienne Strove from NSIDC asked last week what it would take to be convinced of man’s influence. I will respond with a question of my own. What does it take to prove that changes in the wind are driven by changes in CO2?
Extra bonus : Does anyone see a familiar pattern (below) in Greenland temperatures? What year did satellites monitoring the Arctic come on line?
Enquiring minds want to know.
Jon P,
You do realise that “a bit of luck” isn’t necessarily the same thing as “a bit of good luck”, don’t you? That said, I don’t think you’re completely off base but I think it would be more accurate to say Günther thinks the disappearance of arctic sea ice over the long term is a bad thing and that he therefore hopes it will drop low enough this year to thoroughly discredit people who argue that the sea ice is doing just fine and there’s nothing to worry about, resulting in effective action to prevent the expected long term decline if we continue with business as usual. Being able to say I told you so is nice but it’s primarily a means to the end of mitigating climate change, not an end in itself.
Jeff P
Using your methodology, a forecast of zero would be ideal – because it would never be “busted.”
Doesn’t work that way in target shooting. Winner is closest to the bullseye. You are being disingenuous.
Dave says:
August 31, 2010 at 8:59 am
“Second straight day of gain on the 30th.”
Actually, no. I thought so too, but they revised the previous day’s number to a bigger increase (to almost 10 K) so on the 30th they now show a >4K decline. (Of course that could change if they revise the 30th later.)
Here are the present numbers:
Aug 28th-5,342,656
Aug 29th-5,352,500
Aug 30th-5,348,281
Most years (in the relatively short record) the first extent increase occurred between about Sep 1st and Sep 4th, with only one I believe earlier than Aug 29th. DMI has reported above average temps for the last few days so it seems reasonable to assume that the increase in extent is due to some diverging ice. If temperatures stay unusually high for a couple more days (per DMI) it wouldn’t seem to be surprising to get a few more days of large drops in extent. That, I believe, is what Steve Goddard was saying in one of the comments as well. (A drop of 300K or so after the first extent increase date isn’t that unusual, by the way, even when it occurred in early Sept.)
One thing I find interesting about the DMI data at http://ocean.dmi.dk/arctic/meant80n.uk.php is how far above average the temps have been during the last four months of the year in this decade. 2004 was the only year even close to the average temperature line and even that appeared to be above average. Other years rarely hit the average for more than a day or so, with the past 5 or 6 being really warm.
Yet this pattern doesn’t hold for the spring months where temps in the Arctic seem to oscillate around the average after January or so. Anyone have a plausible explanation for this (other than “Hey, that’s the weather for you.”)? Temperatures in the summer months (per DMI) have actually been below average for much of the decade, so it would seem to me that perhaps the temperature behavior over the last few months of the year has more to do with the low arctic ice extent in recent years than does the temperature behavior in the summer months. That is, less ice is formed in the first few months of the re-freeze, so there’s less to melt come summer. Anyway, gives me something to watch once the melt season has ended.
Rod
Rod Everson,
“Most years (in the relatively short record) the first extent increase occurred between about Sep 1st and Sep 4th, with only one I believe earlier than Aug 29th. ”
Your belief is based on insufficiently thorough research. August 24th showed an increase in extent in the JAXA record in both 2002 and 2006.
Djon says:
August 31, 2010 at 10:08 am
I think you should analyze what you wrote and try to follow your own logic. Hint: Do you really think getting below 5M2KM this year is going to suddenly change the world view to initiate a change in the “business as usual”? People will change to alternative fuels when they are affordable, not becasue some yahoo on a blog is rooting for something he believes to be bad thing, to happen, to score debate points.
Example. I really do not believe in CAGW. I do not want government enforced drastic measures to control CO2 however, I just bought a VW Jetta TDI, Why? because it was more cost effective than any comparable gas (even hybrid models) vehicles at the time of purchase. The 40+ mpg is all gravy from day 1.
Relying/depending/expecting a government solution to your perceived problem will not be effective.
stevengoddard says:
August 31, 2010 at 10:16 am
Jeff P
Using your methodology, a forecast of zero would be ideal – because it would never be “busted.”
Doesn’t work that way in target shooting. Winner is closest to the bullseye. You are being disingenuous.
———————————–
Steve,
If you want to predict an ice free arctic no one is stopping you.
You’ve certainly changed your tune from earlier in the year when you were saying that your prediction of 5.5 million K^2 was too conservative and the minimum would be much higher.
No, this isn’t anything like target shooting. You proposed a theory that arctic sea ice is recovering and the test of that theory would be a minimum extent above 5.5 million K^2 in 2010. The extent has dropped below that casting serious doubt on the validity of your theory.
Lastly, it would be nice if we could have this conversation without name calling or questioning my sincerity. Calling me disingenuous is just hurling insults and adds nothing of substance.
P.S. if you still regard your theory of sea ice recovery in play what are the minimums you predict for 2011 – 2015? Based on your theory they should be increasing year after year.
Djon says:
August 31, 2010 at 11:52 am
You know that when someone says “I believe” it usually means that they did not research it and are unsure about their statement. Even a reader with basic comprehensions skills knows enough that the statement in question should be investigated. On the other hand your attack mode is quite effective at convincing me to read what you write more carefully, um I ment more infrequently.
Djon says:
August 31, 2010 at 11:52 am
“Your belief is based on insufficiently thorough research. August 24th showed an increase in extent in the JAXA record in both 2002 and 2006.”
You’re correct, and you caught the “I believe” in my statement. 2002 was missing some records right around the beginning of September and so I had ignored it the first time I checked the data. I re-checked it in the middle of writing that post but then overlooked correcting what I’d written. Sorry about that and thanks for clearing it up for everyone.
Rod
Jeff P says:
August 31, 2010 at 12:17 pm
Stop your lying, it is getting beyond ridiculous.
Jon P,
Are you saying that you don’t want government enforced drastic measures to control CO2 because you don’t believe in CAGW or that you wouldn’t want government enforced drastic measures to control CO2 even if you did believe in CAGW? Can we agree that the latter position would be foolish, unless you had some plausible non-government solution to the problem? Personally, I don’t think people voluntarily buying more fuel efficient cars (and, no doubt, taking other efficiency measures they consider cost effective) is going to be enough of a response to the threat.
Also, do you disbelieve in the efficacy of government solutions to all problems too large or complex to be addressed by individual action or is climate change somehow a special case? Government action has, in fact, solved some pretty big problems over the course of time, though climate change is admittedly a bigger one than any in the past I can easily bring to mind given the long time frame before catastrophic impacts are likely, the gradual nature of the changes involved, the need for international cooperation to address it, etc.
And no, I don’t think a minimum this year below 5 million square kilometers is going to end all debate and lead to immediate strong action. However, I’m not aware of any rule saying public policy debates have to be settled in one fell swoop. In my view, every little bit of evidence helps and arctic ice, as one of the more closely watched indicators of a warming world, is one of the more important pieces of the evidentiary case for climate change being a problem that needs to be addressed.
Jeff P
If you need to twist other people’s words to get your point across, then your point is worthless.
Jon P,
“You know that when someone says “I believe” it usually means that they did not research it and are unsure about their statement.”
This from the person who only a few hours ago wrote “I really do not believe in CAGW.”. Are we to understand that use of the phrase “I really do not believe” is usually indicative of thorough research? For future reference, is it the “do not” that does it or the “really” or are both necessary to convey this subtle nuance?
Jon P says:
August 31, 2010 at 12:28 pm
Jeff P says:
August 31, 2010 at 12:17 pm
Stop your lying, it is getting beyond ridiculous.
——————-
Jon P,
So much for civility….
What precisely is the lie that you are referring to?
In case anyone else interpreted my response to Rod Everson as an attack, I’d like to say it wasn’t intended as such, just as a reminder to all that care should be taken when making factual assertions in any forum. I’m glad Rod, at least, seems to have taken it as such.
stevengoddard says:
August 31, 2010 at 12:39 pm
Jeff P
If you need to twist other people’s words to get your point across, then your point is worthless.
———————-
I agree.
Since this is addressed to me I presume that you think I have twisted your words. What exactly did I get wrong?
Djon says:
August 31, 2010 at 12:43 pm
What does the “C” stand for in CAGW? You sure type a lot of words and say very little.
Your prior post, the former is my answer. People are volunterring to buy more fuel efficient cars? lol They will buy them when they make economic sense. Are you insinuating that government should transition “volunteering” to “mandating”?
So just so we are clear, loss of ice in Artic bad caused by CAGW, but no loss of ice in Antartic is OK, because it is different. High temps in Moscow = CAGW. Low temps in South America, southern California, etc = weather. Government is the model of efficiency where capitalism is bad and evil and corrupt. Nothing anyone says, writes, displays will delude the confidence that you have in the “threat” that we “face”.
Yep planet has warmed, but it is not catastrophic and the only evidence that you have that it will be is models. So you must “believe” it, because you certainly cannot “prove” it.
Jeff P,
I never said anything of the sort. I made an estimate of 5.5, the rest is a straw man fabricated up by you.
Jeff P says:
August 31, 2010 at 1:07 pm
“You’ve certainly changed your tune from earlier in the year when you were saying that your prediction of 5.5 million K^2 was too conservative and the minimum would be much higher.”
Steven discussed about conditions that could affect his prediction one way or another, all summer. He never changed his 5.5 number. The above is a lie. I said it without anger or any other emotion you may wish to project. Would you have “felt” better if I said it was not truthful? or not accurate?
Djon says:
August 31, 2010 at 1:06 pm
I wish I could hear the words you type, I can only imagine the condescending tone of your voice, like nails on a chalkboard to my ears.
Djon says:
August 31, 2010 at 10:08 am
Jon P,
You do realise that “a bit of luck” isn’t necessarily the same thing as “a bit of good luck”, don’t you?
———–
I’ve been wondering what other interpretations there might be of ” a bit of luck” and the only one I’ve come up with is “a lot of luck”, but still where the luck is good and not bad.
I don’t suppose you’d indulge me with an example of a context in which it might refer to bad luck, or even a neutral luck that is neither good nor bad.
Pretty silly, I’ll grant you, but the underlying point that you go on to allude to is the very human desire to be vindicated in one’s opinions.
I would ascribe it a much greater significance than you appear to do, and that would be at the expense of the eminently sane rationale such as that which you credit Mr. Cherrytree with.
Of course, we have very grown-up terms acknowledging the phenomenon, like confirmation bias, but none of it goes into a numerical model.
Oliver Ramsay,
Okay, I’ll stipulate that no one I’ve ever encountered commonly uses the phrase “a bit of luck” with other than good luck in mind. Perhaps I shouldn’t have attempted any sort of play on words there. I was thinking of Steven’s relatively recent emphasis on saying that winds and their impact on the extent are a crapshoot, and that chance isn’t good or bad independently of our reasons for preferring one outcome over another. If you choose to think less well of Günther’s possible reasons for apparently wanting a fairly low minimum than I, well, neither of us are mind readers. I’m glad we can at least agree that the possible motivation I suggested he might and, in my view, likely does hold is eminently sane. Differences in our level of cynicism about people, I can certainly live with without thinking you’re foolish,.
Djon says:
August 31, 2010 at 2:48 pm
How is that team defense working out for you?
My current Monday (8/30/2010) Arctic sea ice extent minimum (bases on JAXA 2003-2010 statistics inclusive) is 4.92E6 km^2 (standard deviation = 0.09E6 km^2).
Note this includes the last two days of JAXA data which have basically flatlined.
The next three days will see a little decline, then back to flat.
Interesting to see the passage of the apocalyptic iceberg up in north-western Greenland over the past few weeks:
http://ocean.dmi.dk/arctic/images/MODIS/Kennedy/20100810AQUA.jpg
http://ocean.dmi.dk/arctic/images/MODIS/Kennedy/20100830AQUA.jpg
Fragmented a wee bit, but it’s barely poking its nose into the Nares Strait (which, it would appear, isn’t far from freezing up for the winter).