Steve McIntyre on Climate Audit brings our attention to an interesting sea ice extent forecasting “contest” conducted by the Study of Environmental ARctic CHange (SEARCH). With the end of the Arctic melt season likely just a few days away, it appears that the experts have a lack of forecasting skill for the subject they are experts in.
SEARCH writes:
We received 13 responses for the September Outlook based on July data (Figure 1). Estimates for September sea ice extent are in a narrow range (4.2 to 5.0 million square kilometers), as were the Outlooks based on May and June data. As the submitted uncertainty standard deviations are about 0.4 million square kilometers, most of these Outlook expected value estimates overlap. All sea ice extent estimates for September 2009 are much lower than the past climatological extent of 6.7 million square kilometers.
Here’s the SEARCH graph (Figure1 PDF available here) showing forecasts from several well known Arctic experts and organizations. I’ve added the most recent available data, the September 6th ice extent from IARC-JAXA of 5,345,156 square kilometers in magenta for a current reference.
While we can’t be certain what nature will reveal as the final number, it is likely that the end number will end up somewhere between 5.1 and 5.25 million square kilometers. What is most interesting is that it appears that all of the Arctic experts overestimated the amount of melt back in August, using July data as a forecast basis.
McIntyre made his own prediction two weeks before this report was published saying:
2009 is now slightly behind 2008. My prediction is that 2009 will end up over 500,000 sq km behind 2008.
His wording is a bit confusing, but what he means is that the final number will likely be about 5.15 million square kilometers.
As Steve McIntyre writes:
That prediction didn’t look all that great a couple of weeks later, but right now it looks pretty much right on the money. As of today, 2009 is 470,000 sq km behind 2008 and the chances of 500,000 seem pretty realistic.
That my guess was so close was due more to good luck than acumen, but there were some reasons for it. Canada has some exposure to northern weather and it has been a cool summer here and very cool in northern Ontario. 2008 had not been as big a melt as 2007 and presumably there was presumably a bit more two-year ice in 2009 than in 2008. While 2008 and 2009 were about even at the time, the trajectories looked different and it seemed to me that 2009 might stabilize at a higher level than 2008.
And yet in early/mid August, these factors didn’t seem to be on the minds of the official agencies since, as noted above, EVERY official agency substantially over-estimated the melt.
Back in early March 2009, I asked WUWT readers what they thought the 2009 Arctic sea ice extent would be.
With 67% saying then that the 2009 extent would be greater than 2008, and with McIntyre’s forecast also, it appears that bloggers and laymen just might have have a better handle on sea ice extent than the majority of Arctic experts themselves.
The next few days will be very interesting.
Roger,
What do you think icebreakers do?
And how do you think they supply all the towns in the Arctic?
Of course they ship the goods in in the Summer.
From 1937. nothing new.
“Across the Pole is the Northeast Passage to China along the top of Norway & Russia. Sebastian Cabot initiated its search in 1553. Henry Hudson twice attempted a passage but it was not until 1879 that the route was navigated. Now Russia currently operates 160 freighters on summer schedules in the Northeast Passage’s more open but colder waters.”
http://www.time.com/time/magazine/article/0,9171,770864-2,00.html
I like this figure. It puts the graphic back to with 1979-2000 (including 1996).
Also this graphic: http://nsidc.org/images/arcticseaicenews/20090908_Figure3.png
I shows that 2005, 2007, 2008 and 2009 are the lowest since 1979.
So this is a longer trend.
Looking at the graph, the blue line points to the top of 2009 (highest in the last three years) and top of 2005 (also a high point). Does not seem like overblowing it. In my view, I would have placed the blue line through 2008 because 2009 seems like a peak.
We are back to the usual 10% sea ice lost per decade (8.7%). So summer ice free by 2100 still makes sense.
Would be interesting to see another growth next year. It would be the first time since 1979 that we would have three years of growth.
I want to see the results next year.
With El Nino kicking in, if we can have growth again, it would be extraordinary.
Can anyone see a growing trend in there?
Ron de Haan (12:54:05)
Thanks for the link to the Piers Corbyn interview.
For me very much a “But of course!” moment.
shocking manipulation of data here: go the the publicly available data from the temperature stations at Svalbard, Resolute, Barrow, Eureka and Talkeetna. There is an irrefutable and steep rise in Arctic temperatures recorded at each of them, whether you take five, ten or twenty year timeframes. Denialists have to deal with this.
REPLY: Oh we are, and you should too, such as questioning “what caused it”?
“Valentinus (05:43:56) :
shocking manipulation of data here: go the the publicly available data from the temperature stations at Svalbard, Resolute, Barrow, Eureka and Talkeetna. There is an irrefutable and steep rise in Arctic temperatures recorded at each of them, whether you take five, ten or twenty year timeframes. Denialists have to deal with this.”
Why don’t post a link instead of bloviating, but take a look at the DMI-site first (on the right of this blog).
I have it all figured out; the problem with the disappearing Arctic ice that is.
The US, and Canada, and the Russkies all have a bunch ov vandals running artound up there in steels hips, breaking up the ice sheets so the wind and tides can blow it all out of there.
I think Green piece and the Sierra Club should sue to get these destructive vehicles out of the Arctic ocean.
Here we are complaining about ice sheets in Antarctica breaking up from natural causes, and we have hoodlums busting up the arctic ice willy nilly; shameful !
George
Alexej Buergin (07:26:09) :
Why don’t post a link instead of bloviating, but take a look at the DMI-site first (on the right of this blog).
Which is completely irrelevant to the subject of ‘Arctic warming’, hint: would you measure the temperature of a room by putting the thermometer in an iced drink?
Shawn Whelan (18:48:29) wrote:
“Roger, What do you think icebreakers do?”
I wasn’t denying that they break ice when I said “ridiculous.” I was characterizing your ridiculous claim that people don’t believe that icebreakers break ice. Here’s what you said:
“This what icebreakers do in the Arctic. (break ice)
Some of course will not believe this.”
Name one person who disputes that fact.
While you’re at it, name one commercial ship that is “busting through the Southern route of the NW Passage.“
PS: Of course commercial ships, usually preceded by icebreakers, are and have been delivering goods to towns on the Arctic Ocean. But that isn’t the same thing as the warmists’ prediction that the passages would soon be open in the summer to ordinary shipping as shortcut shipping routes from one side of the globe to the other. That’s what’s ordinarily the “message” when news about arctic shipping is ballyhooed.
Pam:
“Would be interesting to see another growth next year. It would be the first time since 1979 that we would have three years of growth.
I want to see the results next year.”
—
Winter extents: 2007, 2008, and 2009 all were greater than 2006.
Summer melt:
2006 was greater than 2005;
2008 greater than 2007,
2009 greater than 2007 (by 25%) and 2008 (by 14%).
I think you have some things confused.
The 2006 summer melt was less than the 2005 melt, and the 2007 “melt” was by far the greatest since 1979; 2008 was a lot less, and 2009 is going to be less yet.
So where did you get your data; the graphs are up ther on the right hand side, and the JAXA website can give your the actual areas remaining ?
George
Did we finally hit the minimum on 9/13 at 5.25 million square kilometers? That’s slightly under the 5.32 million square kilometers back in 2005.