by Jeff Id
As we approach the Arctic Sea Ice minimum, a lot of eyes are looking and projecting what the minimum will be. In a previous post I calculated the centroid of the sea ice as a method for determining how the weather patterns were affecting the data. About a month ago, it seemed that the weather pattern was going to support a leveling off of the sea ice shrink rate so that’s what I predicted and that’s what happened. The curve cut across the 2008 line and reached over until it touched the 2005 line.
![AMSRE_Sea_Ice_Extent[1]](http://noconsensus.files.wordpress.com/2009/08/amsre_sea_ice_extent11.png?quality=75 "AMSRE_Sea_Ice_Extent[1]")
Unfortunately, from this centroid video, it looks like the winds from the Southeast in the image which created the huge reduction in Sea Ice in 2007 appears the have restarted this year. It’s already starting to accelerate the melting which caused this year’s red line to dip below the 2005 green line.
The shift in weather pattern is most visible in the shadows on the ice which are actually clouds blowing through. The shadows indicate the 29GhZ microwave data is sensitive to clouds which is part of the noise in the long term signal.
Below is an updated 2007 – present video.
Click to play
If you missed the original video which is full record length and shows the unusualness of the current weather patterns in the last 30 years, it’s linked at this post below.
Arctic Ice Weather Patterns
That post explains the arrow vector and the source of the data.
I’m going to update my prediction from this shift in weather. Now I think the ice level will dip quickly downward in relation to 2005 but will still sit above the 2008 minimums. It looks like the ice has been thinned by the recent blasts of weather from the southeast and if this pattern maintains itself the dip will be fairly strong. Of course I’m an engineer and not a meteorologist so we’ll see.
There is only 21 more days of melt left on average. The average minimum is on September 12th (2007 went a few days over this but not by much).
The average melt per day fluctuates quite a bit right now but it declines steadily from about 45,000 km^2 per day right now down to 5,000 km^2 on the 12th.
So take 20,000 times 21 days equals just 420,000 km^2 below todays number from Jaxa and on Sept 12th, the minimum is 5.4M which will be above 2007, 2008, 2002 and 1999.
Hi,
If you take the years listed you will see that it may start to dive in the very short term but historically it will level to that of 2005. Even 2007 at this time or year could not go down that fast. So I will bet it will be 2005.
Frederick Michael (18:55:38) :
This map does NOT confirm the high wind speeds.
http://www.athropolis.com/map2.htm
thanks for the link. Interesting. Maybe it was a transient wind pattern.
The AMSR-E update is out (normally around 11pm eastern time) and the Arctic Sea Ice Extent took a big hit.
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm
Note:
1) The download data button gets you a CSV file, which is useful.
2) The 5,737,344 number for August 23rd will be revised sometime in the next 12 hours or so. It’s usually upwards, especially after a big drop, but that’s not a guarantee. (August 22 was 5,823,281.)
3) The plots has some misleading features. The days are plotted 1-365 with the months just marked off as 1/12 of a year each — so the date can get off a bit. Also, since they don’t compensate in a leap year, they’re showing August 22, 2008 at the same horizontal position as August 23 in non-leap years.
Isn’t it a whole lot easier to just say, “Great!” when the AGW’ers talk about less summer ice in the Arctic? Shouldn’t we make them explain what they are so afraid of? All we have to do is say, “Not as much ice as recent years eh?, Well – what’s the harm in that??”
So to achieve a record “melt” this year we need some fierce winds to blow the ice away!
The ice melts elsewhere. That implies a cooling process. Current exposed polar sea will be radiating out to sunless space. Looks to be a cold winter up in the Arctic this year. 🙂
Yes, Frederick, the Arctic lost 85937 km2 yesterday, which is very much for this time of the year. We’ll see…
One picture says more than 1000 words:
http://www.klimadebat.dk/forum/vedhaeftninger/seaice4years.gif
I will never forget the Independent headlines in June 2008 (and have saved a copy for future reference):
“Exclusive: Scientists warn that there may be no ice at North Pole this summer”
And first sentence:
“It seems unthinkable, but for the first time in human history, ice is on course to disappear entirely from the North Pole this year.”
By ‘Science’ Editor, Steve Connor
http://www.independent.co.uk/environment/climate-change/exclusive-scientists-warn-that-there-may-be-no-ice-at-north-pole-this-summer-855406.html
Steve Connor later sheelpishly aknowledged the inaccuracy (but stood by it) in:
“Steve Connor: Best still on for ice-free North Pole” (though now not a headlines, just ‘Science notebook’.
He says “How could we have got it so wrong? First, I’d like to make it clear that we of course stand by our story.” Going on to conclude:
“It is surely only a matter of time before we will see an ice-free North Pole, and indeed a totally ice-free Arctic Ocean,during summer. My own bet is that we will see the former within the next decade.”
‘Within the next decade’ still seems a bold prediction.
http://www.independent.co.uk/opinion/commentators/steve-connor-bets-still-on-for-icefree-north-pole-949661.html
Bill Illis (19:55:47) :
Have to disagree with you Bill. We have had two consecutive days of around 80,000 in decrease and that is highly unusual this time of year. If it should average 40,000 per day rather than 20,000 (not saying it will), look at where that would put the minimum. I still think we will end up slightly higher than 2008 but the race with 2005 appears to be over. As in all things though, Mother Nature will decide where it ends up definitively, not us humans.
Why not use longitude instead of NSEW?
Michael Jennings (4:25:05)
Yes, a couple of days of 158,000 km^2 in melt total kind of throw my calculations out the window (although there is is still 20 days left of declining melt – each day compared to the average will determine the final number).
“Frank Lansner (04:11:28) :
One picture says more than 1000 words:”
Nice one Frank.
Greenpeace give up…
“09:16 am CDT Aug 20, 2009
(ThePoles.com/TheOceans.net) Eric Phillips who is on a Greenpeace vessel at the coast of Greenland sent an update about their recent activities. …
Here goes Eric’s report:
Peterman glacier
“After 5 weeks in the Petermann and Humboldt glaciers region of Northwest Greenland, we have had to steam south in order to meet our arrival date at Sermilik Fiord on the east coast.”
“The Petermann was expected to break up this season but the freeze has begun and may just hold it in place until next summer. Petermann is the longest floating glacier in the northern hemisphere and an area over 100 sq/km is expected to break away, if not this year, then next.””
http://www.theoceans.net/news.php?id=18605
I add, and probably breaks off regularly. A fed glacier must do this.
Adam from Kan.
Go to:
http://ocean.dmi.dk/arctic/meant80n.uk.php
for Arctic temp information. It would be fun to see if the temp presented at the web site is a leading indicator of future ice area/extent.
Flanagan – While ice area/extent numbers have all those digits, not all are significant. There is about a 10% error area/extent estimation numbers, especially in the summer.
Bill Illis (05:58:25) :
NSIDC’s Arctic sea ice concentration map shows few pixels ready to drop below 15%, so expect things to level off in a week or so. Also, 2005’s mysterious drop in late Sept. means that 2009’s minimum could still be above 2005’s.
We’re getting some negative numbers here.
http://www.athropolis.com/map2.htm
“Flanagan (01:25:25) :
Yes, Frederick, the Arctic lost 85937 km2 yesterday, which is very much for this time of the year. We’ll see…”
Did it really ? Over in Bergen the ice-extend had an UPTICK again:
http://arctic-roos.org/observations/satellite-data/sea-ice/ice-area-and-extent-in-arctic
And, by the way, the correct scientific number for AMSR-E would probably be 86 000 km^2, maybe 90 000 km^2. The other digits are nonsense.
Correction: since 5823281-5740625=82656 I should have said: lost 80 000 km^2
I’m famous again, thanks Anthony.
Let’s see,
Bob Tisdale.
I’m sure it’s possible to do Hovmoller plots, is there something you would like to see in particular on each axis?
The ice did appear to be thicker multi-year ice this season (less gray) until the last few frames where I noticed some thinning at the windward edge.
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Some notes for everyone:
My prediction of ice shrinkage should be taken with a grain of salt because it’s really based on very little information. The clouds just started racing upward from the Bering Strait and the centroid vector really shifted and elongated. There are only 4 (I believe) years in the 30 year record which have shown that sort of off kilter centroid. Two of those years were 07 and 08 which had high melt once the pattern started. We are of course near the end of the melt season. The full 30 year record is at the link to the other air vent post.
DeWitt Payne pointed out on tAV thread that extent has gone down but Area has increased over the last 3 days. This probably indicates a compaction of the ice against the Greenland continent.
Once again, I don’t think the ice is melting, I think it is thickening. IE, ice edges are being pushed together and piled up into psuedo-multiyear ice packs. See the following for great info on current wind patterns. These strong winds say to me that ice is piling up at the center and any “ice extent” or “ice area” data will be an artifact of this process, not melting.
http://squall.sfsu.edu/gif/jetstream_norhem_00.gif
That’s very nice Jeff. I like the slow rate of the video; there are so many nooks and crannies to look at that I need time to see it all. I liked watching Hudson’s Bay fill up; and I agree the wind vector is a useful addition.
If you ever want to add some knobs to the video; a Pause and Resume would be nice so we could compare the picture with the clock to get familiar with what it looks like at any calendar date.
Data is no good in itself, if there isn’t a way to present that data in an infromative way. Your video is an example of efficient data presentation.
Thanks for the effort; it truly is helpful.
George
On that Ian Pilmer link, I sometimes wonder if he knows what he’s talking about. In one paragraph he writes that in the past, carbon dioxide levels were 1,000 times higher than the present.
Utter nonsense!
Thought: Maybe a return to normal extent, area, and thickness of ice is two fold:
Lower Summer melt due to colder temperatures in the air and ocean.
Lower Summer melt due to wind compaction instead of transportation.
Maybe I’m wrong, but it appears that the focus of the NSIDC’s semi-monthly Arctic sea ice report at http://nsidc.org/arcticseaicenews/ has recently changed. Until recently, it seemed that most reports contained an alarmist reference to “global warming.” The current report (dated August 18) does not mention that term at all. Instead, recent changes in Arctic sea ice melt patterns are explained by a very good analysis of how atmospheric circulation patterns push ice around. The following passage is particularly relevant to recent comments in this thread:
Recent research by Stephen Howell at the University of Waterloo in Canada shows that whether the Northwest Passage clears depends less on how much melt occurs, and more on whether multi-year sea ice is pushed into the channels. Counterintuitively, as the ice cover thins, ice may flow more easily into the channels, preventing the Northwest Passage from regularly opening in coming decades.
Frank Lansner (04:11:28) :
“One picture says more than 1000 words:”
http://www.klimadebat.dk/forum/vedhaeftninger/seaice4years.gif
Reply: Thanks for the picture, shows exactly what’s going on up there.
Pamela Gray (10:24:30) :
Lower Summer melt due to colder temperatures in the air and ocean.
Lower Summer melt due to wind compaction instead of transportation.
Reply: I’ll go with that hypothesis – perhaps 2009 will still turn out to be close to the 2005 ice volume. Arctic temp still below freezing and with less of the more penetrating short wavelength UV around the ice should survive better.