This week was a true roller coaster ride with Arctic Sea Ice. It is best summed up by looking at the JAXA graph for extent, shown below:
Below, see the area of interest magnified.
I’ve added the 5 million square kilometer line for reference.
The roller coaster ride actually looked for a day like it might cross the 2009 line, but soon turned down again, ending this week at 5,142,813. Here’s the recent JAXA data
08,28,2010,5342656 08,29,2010,5352500 08,30,2010,5348281 08,31,2010,5329375 09,01,2010,5332344 09,02,2010,5304219 09,03,2010,5245625 09,04,2010,5192188 09,05,2010,5142813
Source: http://www.ijis.iarc.uaf.edu/seaice/extent/plot.csv
JAXA sea ice area has dropped to 2008 levels:
JAXA AMSR-E Sea Ice Area – click to enlarge
Sea ice concentration from JAXA:
While JAXA shows extent now lower than 2009, DMI and NANSEN plots show it to be about even. The differences in observing sensor/platform AMSRE -vs-SSMI and methodologies at agencies are in play.
Above: Danish Meteorological Institute Arctic Sea Ice Extent – 30% or greater. Note that while this graph shows 30% concentration at the cutoff point, it is valuable to compare.
Above: NANSEN Artic ROOS- Sea ice extent 15% or greater – click for larger image
The differences appear to be in the low end of concentration, the 15% to 30% range. It suggests that the brief gains we saw may be wind related, blowing floating ice around, compacting it when winds are strong versus allowing expansion when winds are weak.
Temperature, after holding near freezing, now appears headed sharply downward.
Above: Danish Meteorological Institute – Mean Temperature above 80°N
Some light refreezing may take place before the end of September, which could minimize the ability of wind to sharply change extent like we saw recently.
With all these variables in play, choosing a winner will be as much a game of luck as of skill. Based on what we’ve seen, it seems probable that it will come from the middle of the pack between 2008 and 2009.
From SEARCH:
The estimates from the scientific community range from 4.0 to 5.6 million square kilometers, with 8 of the contributors suggesting a September minimum below 5.0 million square kilometers, 3 contributors suggesting a minimum of 5.0 million square kilometers, and 5 contributors suggesting a September minimum above 5.0 million square kilometers. Two contributors forecast a September minimum below that of 2007 at 4.0 million square kilometers and 3 contributors suggest a return to the long term downward linear trend for September sea ice loss (5.5 to 5.6 million square kilometers). None of the contributors indicate a return to the climatological sea ice extent of 6.7 million square kilometers.
Including all 18 contributions gives a September ice extent minimum of 4.8 +/- 0.77 million square kilometers, with a range of 2.5 to 5.6 million square kilometers.
Individual responses were based on a range of methods: statistical, numerical models, comparison with previous observations and rates of ice loss, or composites of several approaches.
Why has the previously prolific sdteve goddard chosen to
Take a step away now?
Right at the crescendo lf the subject he has been at the centre
Of for months he suddenly disappears?
Am I alone in thinking its odd?
2008 was a cold year and then 2010 is a warm year with 2009 in between. The real cooling starts now. This La Nina is shaping up to be a big one. Joe Bastardi was spot on with his forecast on the ice extent, i.e. ice recovery one step back, two steps forward, and his prediction that there would be significant cooling, which he made before the La Nina started, looks like it will be spot on as well. As Joe predicts, in two years the warmists will have great difficulty justifying their position.
jason says:
September 7, 2010 at 1:09 am
“Why has the previously prolific Steve Goddard chosen to
Take a step away now?
Right at the crescendo lf the subject he has been at the centre of for months, he suddenly disappears?
Am I alone in thinking its odd?”
No Jason, you’re not alone.
This seems to indicate the downwards trend started before 1976
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seasonal.extent.1900-2007.jpg
Looks like from the 1950’s onwards.
Andy
An uptick today in the DMI 30% extent. Generally it looks like the DMI 30% extent bottoms out earlier than the 15% extent measurements. It is still possible that the DMI 30% extent wont go below the 2009 minimum.
EFS_Junior says:
September 7, 2010 at 12:38 am
Dont hold your breath.
Andyw:
Looks like from the 1950′s onwards.
I wonder what the error margin for those pre-satellite measurements is…
Amino Acids in Meteorites says:
“Do you care about the people that starve to death from food shortages caused by biofuels?”
I don’t agree with Biofuels at all. It is fiddling whilst Rome burns. In order to resolve large issues you have to fixe the core underlying problems.
Biofuels are targetting the issues not the problem.
Regarding surfacing submarines: I wonder if observant people have taken into account the thermal energy released by their engines/reactors?
They will have to be operational and powered-on during the surfacing, and the nuclear reactors in particular will always remain active (or at least to me that would seem very likely). The heat will have to be dissipated somewhere outside the boat — there would be a mighty big barbeque inside the boat were it not the case! Adding a few megajoules of thermal energy into a relatively small pool of water would make it melt spectacularly, as seen in the pics.
AndyW says:
September 7, 2010 at 2:40 am
And how were those disparate datasets spliced together?
What adjustments were made?
Can those results be duplicated?
Beware spliced data sets.
@Graeme
Re: It clearly shows an almost straightline downward trend since 1969, which would imply that CO2 is not the major factor in that trend (there’s no real change in the rate, despite increasing levels of CO2).
Actually, if you add trend lines for five year periods or even each decade, thereby factoring out most of the noise, it would seem that a fundamental shift occurred mid 70s – I don’t know – somewhere between ’73 and ’77.
Sound familiar?
Arctic Sea Ice Area:
http://www.robertb.darkhorizons.org/seaice.area.ANT_arctic.jpg
2010 max sea ice in the Arctic was only .5 M km^2 below the level attained in 1981.
Arctic min sea ice has dropped 2 M km^2, while the Antarctic has gone exactly nowhere.
Arctic max sea ice has dropped 1 M km ^2 since 1979, while the Antarctic has risen 1M km^2.
The data is all over the place, like drippy cheeseburger condiments.
But, 31 years ago, in 1979 (oh what a convenient starting/ending date THAT is), all the rage was the Ozone Hole in the Antarctic with UV burning all life to a cinder, and the Coming Ice Age indelible proof of cyrogenic doom in the Arctic descending upon civilization.
Now, this is what I call Cyclic Bi-Polar disorder.
Message to those unable to sleep at night over climactic disaster disorders that have not materialized:
Don’t throw your life away over flimsy marginal data. Suicide is not the answer.
For the rest of us, there is adaptation and a couple of deep breaths.
AndyW says:
September 6, 2010 at 10:18 pm
No, because as a percentage of the total amount of ice in those regions the loss in the Arctic is a lot more than the gain in the Antarctic.
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For measurements that have only been taken for 31 years, and using accounts that go back to the 1800s of a clear NW Passage, submarines popping through to the North Pole in the 50’s [they definitely can’t do that now]….your definition of “loss” is at best, a guess.
Natural variability, bud.
Natural variability.
http://www.john-daly.com/polar/arctic.htm
Chris
Norfolk, VA, USA
“Cyclic Bi-Polar Disorder”
LMAO. Good one, Robert!
Chris
Norfolk, VA, USA
Walt Meier says:
September 6, 2010 at 7:35 pm
Latitude, I’m not sure what point you are trying to make.
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Looking at the graphs that Anthony posted, there can be huge differences in Mar and Sept, that still come back together in May and Dec.
That’s all.
phlogiston says:
September 7, 2010 at 3:06 am
An uptick today in the DMI 30% extent. Generally it looks like the DMI 30% extent bottoms out earlier than the 15% extent measurements. It is still possible that the DMI 30% extent wont go below the 2009 minimum.
EFS_Junior says:
September 7, 2010 at 12:38 am
Dont hold your breath.
_____________________________________________________________
Kind of like robbing Peter to pay Paul.
Considering that an ensemble of Bremen, NSIDC, and JAXA (all three using the 15% concentration threshold) over the past dozen days (or so) show a nearly linear trend of -32K/Day (R^2 = 0.89) there is absolutely no reason necessary for holding one’s breath.
If and when all three of the above indicies drop below 10K-30K/Day concurrently for a few sequential days, then and only then will we be able to see the light at the end of the Arctic sea ice extent minimum.
It seems to me that all us sceptics are just going to have to sit back and eat some crow for a year (at least) on the Arctic Sea ice extent. There’s no denying at this point that 2010 will fisinsih below 2009, and given current trends (always subject to change) probably below 2008. The gloaters are pouring forth their sarcasm, and so it goes in these debates.
I still have a couple of questions though. First is why a 30 year trend of ice loss on one half of the globe is considered gospel, and never subject to reversal. If there’s one thing all of us should recognize, climate seems to rarely if ever continue trends indefinitely. Many non anthropogenic factors could act to reverse this trend, and soon. We have to follow the trend for a lot longer than 30 years, which seems to me at least an impossibly tiny amount of time in the context of something as hopelessly complex as earth’s climate.
Secondly, I still would like to know what our AGW believer colleagues propose to do about the trend (if it is primarily anthropogenic). When you answer, beware the law of unintended consequences, my friends.
David Gould says:
September 6, 2010 at 7:54 pm
latitude,
For May, this result supports your hypothesis,
=====================================
David, thanks again, but don’t elevate this to a hypothesis, it’s just an observation of the graphs that Anthony posted.
All I was saying is that you can have trends on the extremes that don’t show up in the middle.
You can have a lot less ice all year, that still comes back to what looks to be statistically insignificant in May and Dec,
and have a lot more ice all year, that still comes back to what looks to be statistically insignificant in May and Dec.
Almost the same levels, at exactly the same time each year..
rbateman says:
September 7, 2010 at 4:29 am
AndyW says:
September 7, 2010 at 2:40 am
And how were those disparate datasets spliced together?
What adjustments were made?
Can those results be duplicated?
Beware spliced data sets.
*****************************************
Espen says:
September 7, 2010 at 3:45 am
Andyw:
Looks like from the 1950′s onwards.
I wonder what the error margin for those pre-satellite measurements is…
___________________________________________________________
Well whatever the error before the satellite age it seems to be fairly consistent up to the 1950’s and then drops. Also the splicing has nothing to do with it, it happens a lot later.
The drop from the 1950’s seems to be big enough to take into account worse accuracy in those days, it is not a small fraction change or small trend.
Andy
Amino Acids in Meteorites says:
September 6, 2010 at 11:31 pm
Michael Schaefer says:
September 6, 2010 at 3:54 am
And in that, the arctic ice extend seems to be quite well on it’s way back to normal
I’d say it always was normal. What happened in 2007 I am certain has happened before.
—
Certain based on what? What do you mean by “well on its way back to normal”? What is normal; the 2008 minimum, the 2009 minimum, the expected 2010 minimum, the 1979-2000 average? The latter? If so, it has a long way to go, about 2 million sq km or so. That’s a lot of ice cubes.
Steve’s departure while not surprising is disappointing. He did what few skeptics are willing to do, put out a testable theory (sea ice is recovering), make a prediction based on the theory (arctic sea ice extent minimum of 5.5 million k^2) and let the chips fall where they may.
This is the core process of building scientific knowledge. Undertaken by brave individuals who are willing to be wrong in the search for knowledge and, if wrong, able to then get up and try again.
So while Steve’s theory was not supported by the data his efforts should not be viewed as wasted. His work has been a refreshing departure from skeptics who mock and ridicule scientists from the sidelines while never putting a stick in the sand themselves for fear of being judged they way they judge others.
Has anyone else made the connection between Daylight Saving Time and Global Warming? There seems to be more manmade global warming since we went to DST. Now THAT would be worth looking into wouldn’t it? Bet someone could get a grant for at least $1M per year for several years on that one. Psst.. DON’T tell Mann!
rbateman says:
September 6, 2010 at 8:15 pm
savethesharks says:
September 6, 2010 at 7:21 pm
2010 Global Sea Ice Area is within 1M km^2 of where it was in 1979 on the Cyrosphere Today chart, when one considers where global sea ice spends most of it’s time between the extremes of ranges.
Actually it isn’t (what a surprise).
On average this year so far has been about 1.5 Mm^2 below 1979 and is currently over 2Mm^2 below the 1979 value for this date.
Even if all the Arctic sea ice was gone Mr bateman would doubtless be telling us that global sea ice area was only 5Mm^2 below the 1979 value!
rbateman says:
September 7, 2010 at 5:10 am
But, 31 years ago, in 1979 (oh what a convenient starting/ending date THAT is), all the rage was the Ozone Hole in the Antarctic with UV burning all life to a cinder, and the Coming Ice Age indelible proof of cyrogenic doom in the Arctic descending upon civilization.
Really, I distinctly recall that Farman et al. discovered the Ozone Hole in 1985!
” jason says:
September 7, 2010 at 1:09 am
Why has the previously prolific sdteve goddard chosen to
Take a step away now?2
He is now even more prolific:
http://stevengoddard.wordpress.com/
” AndyW says:
September 6, 2010 at 10:18 pm
No, because as a percentage of the total amount of ice in those regions the loss in the Arctic is a lot more than the gain in the Antarctic. ”
We are only talking about sea ice here; the amounts are remarkedly similar.