This fits right in to what I’ve been blogging about for two years. the 2007 record minimum ice extent was wind driven not melt driven. A significant portion of the ice did not melt in place. It was pushed south by the wind where it melted.
Here’s where the wind is a factor in pushing past the ice arches:
NASA Sees Arctic Ocean Circulation Do an About-Face
Arctic Sea ice loss – “it’s the wind” says NASA
Here’s where ice arches help: Update on Arctic sea ice melt – “Ice pockets choking Northern Passage”
Watch how ice flows in the Arctic: Arctic Sea Ice Time Lapse from 1978 to 2009 using NSIDC data
Today’s Press Release From JPL:
Missing ‘Ice Arches’ Contributed to 2007 Arctic Ice Loss
Animation: View animation (GIF 52 Mb) | View animation (GIF 13 Mb)
PASADENA, Calif. – In 2007, the Arctic lost a massive amount of thick, multiyear sea ice, contributing to that year’s record-low extent of Arctic sea ice. A new NASA-led study has found that the record loss that year was due in part to the absence of “ice arches,” naturally-forming, curved ice structures that span the openings between two land points. These arches block sea ice from being pushed by winds or currents through narrow passages and out of the Arctic basin.
Beginning each fall, sea ice spreads across the surface of the Arctic Ocean until it becomes confined by surrounding continents. Only a few passages — including the Fram Strait and Nares Strait — allow sea ice to escape.
“There are a couple of ways to lose Arctic ice: when it flows out and when it melts,” said lead study researcher Ron Kwok of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “We are trying to quantify how much we’re losing by outflow versus melt.”
Kwok and colleagues found that ice arches were missing in 2007 from the Nares Strait, a relatively narrow 30- to 40-kilometer-wide (19- to 25-mile-wide) passage west of Greenland. Without the arches, ice exited freely from the Arctic. The Fram Strait, east of Greenland, is about 400 kilometers (249 miles) wide and is the passage through which most sea ice usually exits the Arctic.
Despite Nares’ narrow width, the team reports that in 2007, ice loss through Nares equaled more than 10 percent of the amount emptied on average each year through the wider Fram Strait.
“Until recently, we didn’t think the small straits were important for ice loss,” Kwok said. The findings were published this month in Geophysical Research Letters.
“One of our most important goals is developing predictive models of Arctic sea ice cover,” said Tom Wagner, cryosphere program manager at NASA Headquarters in Washington. “Such models are important not only to understanding changes in the Arctic, but also changes in global and North American climate. Figuring out how ice is lost through the Fram and Nares straits is critical to developing those models.”
To find out more about the ice motion in Nares Strait, the scientists examined a 13-year record of high-resolution radar images from the Canadian RADARSAT and European Envisat satellites. They found that 2007 was a unique year – the only one on record when arches failed to form, allowing ice to flow unobstructed through winter and spring.
The arches usually form at southern and northern points within Nares Strait when big blocks of sea ice try to flow through the strait’s restricted confines, become stuck and are compressed by other ice. This grinds the flow of sea ice to a halt.
“We don’t completely understand the conditions conducive to the formation of these arches,” Kwok said. “We do know that they are temperature-dependent because they only form in winter. So there’s concern that if climate warms, the arches could stop forming.”
To quantify the impact of ice arches on Arctic Ocean ice cover, the team tracked ice motion evident in the 13-year span of satellite radar images. They calculated the area of ice passing through an imaginary line, or “gate,” at the entrance to Nares Strait. Then they incorporated ice thickness data from NASA’s ICESat to estimate the volume lost through Nares.
They found that in 2007, Nares Strait drained the Arctic Ocean of 88,060 square kilometers (34,000 square miles) of sea ice, or a volume of 60 cubic miles. The amount was more than twice the average amount lost through Nares each year between 1997 and 2009.
The ice lost through Nares Strait was some of the thickest and oldest in the Arctic Ocean.
“If indeed these arches are less likely to form in the future, we have to account for the annual ice loss through this narrow passage. Potentially, this could lead to an even more rapid decline in the summer ice extent of the Arctic Ocean,” Kwok said.
For more information about NASA and agency programs, visit: http://www.nasa.gov .
========================
h/t to Dr. Leif Svalgaard
Here is another graph that does not get any attention on Wattsup when talking about the arctic.
http://upload.wikimedia.org/wikipedia/commons/thumb/5/53/MilankovitchCyclesOrbitandCores.png/600px-MilankovitchCyclesOrbitandCores.png
Milankovitch forcing. The high lattitudes of the nothern hemisphere should be at the coldest part of the past 5000 and probibly 10 000 years. Guess it does not rile the troops in the right direction.
Robert (22:32:54) :
“Can someone explain to me why even if all ice is gone in the north pole during summer is catastrophic?”
“A little more on the warming this would cause. I couldn’t find anything calculating the precise positive feedback of the albedo loss from losing the summer ice. I did a very (VERY) rough calculation. (If anyone has the real numbers, please post them):
Arctic ice area (summer, 1979-2000 average): about 7 million sq km (1.4% of the earth’s area)
Sea ice albedo: .7
Open water: .08
Summer radiation: 400 Watt/m^2
Duration: 6m/yr
So . . . over 1.4% of the Earth’s surface (.014), for half the year (.5), you get the difference between .7 (120 W/m^2) and .08 albedo (368 W/m^2) (it’s 248 W/m^2). You get a total forcing of about 1.7 W/m^2.
That’s slightly more than the amount of forcing adding by all the anthropogenic CO2 added to the atmosphere to data, so it’s a potentially large source of positive feedback.”
Interesting calculations Robert, but here is the factor that makes proving AGW so difficult. Clouds!
“Frequent cloud cover, exceeding 80% frequency over much of the Arctic Ocean in July (Serreze and Barry, 2005), reduces the amount of solar radiation that reaches the surface by reflecting much of it before it gets to the surface.”
The world’s most greatest scientific victory in the history of mankind was played out in almost all its entirety in the “Geekosphere”.
Call us what you will, Nerds, Geeks, Poindexters, or whatever. Like Sherlock Holmes or Columbo, we figured out who done it so to speak. We’re not 9/11 truthers or birthers chasing our tails, no, we just concern ourselves with the facts, creating constructs that make sense given all the data.
Do you think we will get any of the credit for exposing the greatest scientific fraud in history?
So it is confirmed that a large unusual event, due to higher than normal winds is the reason for the 2007 low Arctic ice level.
Disappointing, but not surprising that the authors had to add speculation about warming to the end of this generally ‘off message’ report.
History shows that varying and unpredictable nature of the annual Arctic ice melt has little to do with CO2, rather it is a result of the chaotic processes of the polar ‘heat-pump’. Another nail in the CAGW coffin.
Having seen the videos of the 2007 wind blown ice departing the Fram Strait there’s no doubt that this was a key factor in the summer 2007 miniumum. I am surprised that there has been such little study of this subject. Also surprised at the researcher’s claim that summer 2007 was the only year they saw ice being transported down the Nares Strait / Kennedy Channel. I was keeping an informal eye on this in August last year using the NASA TERRA/MODIS images (http://rapidfire.sci.gsfc.nasa.gov/realtime/) when ice was clearly breaking up north of the Kennedy Sound and making its way south in early August. e.g. August 3rd 2009: http://rapidfire.sci.gsfc.nasa.gov/realtime/single.php?T092152205 and after a quick look just found the same thing in 2004 (July 28th): http://rapidfire.sci.gsfc.nasa.gov/realtime/single.php?2004210/crefl1_143.A2004210162001-2004210162500.2km.jpg
I am sure there will be other examples. All this shows is that using the Arctic ice extent data as an indication of melting or temperatures, without also monitoring ice transport, is at best spurious.
RE: Dave Wendt (23:19:51) : “Given that the mass balance relationship between increased melting and increased precipitation in Greenland is so little understood, I’d say it’s even money whether the Greenland ice sheet would grow or shrink with all that open water available to fuel snowfall. Check out the lake effects snow records for Buffalo.”
My personal opinion of total Arctic sea-ice melt is that this event will or will not happen whether we like it or not. Your observation may be correct, depending on the severity of the climate cycle. Hopefully the process, if it were to occur, would be so gradual that we would all be able to adapt to the changes.
If the polar bears were to go extinct, I suspect that similar white-terrain adapted animals would evolve after the next freeze cycle.
Dear moderator
I am an editor of a swedish local daily newspaper, the Ystads Allehanda, and I have followed your blogg for some years now. I’t like to get in touch with mr Watts, but fail to find an email adress here at WUWT. The reason is I am about to go to the US and would like to ask him for an interwiev.
Best Regards
Ola Tedin
Reply: I sent you and Anthony emails. ~ ctm
‘We don’t know’
Then stop speculating?
Why did the arches not form? The temperture was similar to past years and low enough to create sea ice. So that ain’t the reason.
A structural arch normally fails due to inadequate workmanship or excessive forces.
Easy really when it’s thought through?
C’mon Tony! You know the answer already. Why read dusty old reports written by people who have actually been there years past when you can
fakemodel it? They sure as heck don’t wanna go there themselves…might get eaten by one of them vanishing polar bears!George E. Smith (22:46:09) :
“Since salt water of more than 2.47% salinity has a positive temperature coefficient of expansion down to the freezing point, then the sea water must shrink…”
Any change in the density of sea water (as result of the above) has direct influence on the ocean currents. In critical areas such as the Labrador Sea, effect of even a small change in the currents could be far greater then elsewhere.
“Labrador Sea currents tightly govern the strength of the Subpolar gyre’s circulation, which is the engine of the heat transport across the North Atlantic Ocean.”
http://hal.archives-ouvertes.fr/docs/00/41/83/04/PDF/NATA.pdf
It’s a scam, it’s a scam. it’s a scam
Our climate is dominated by natural cycles.
Ah, yes, 2007; the year of the panic over the disappearing Arctic ice.
Every summer since 1934 the USSR (and now Russia) has serviced its northern ports (Archangel, et al) via the North East Passage. Every summer, that is, except one: 2007. In 2007 winds blew ice onto that northern coast of such a thickness that their nuclear-powered icebreakers could not force through.
2007: the year ice closed the North East Passage. Connection, anyone?
So the ice blew out and melted (cooling the rest of the oceans) and exposing more open water to radiate heat away into space.
Looks to me like a net loss of heat to space.
No problem here.
Oh, and I second the notion that “It’s the ice breakers”… you have a large expanse of thin ice (relative to it’s width) barely anchored to land. Then you chop it all up with giant ships. SURPRISE! it can now drift more easily…
And that quote about the ice arches only forming in winter is priceless. Gee, ice only forms when it’s cold. Who Knew /sarcoff>
Sorry for the double posting, WUWT website did not respond in the usual manner (I’ll blame my PC).
u.k.(us) (18:33:29) :
“Why, always the doomsday prediction at the end”
Thats to ensure the grants for next year. No comments including the trick words, no happy smiles from the bean-counters.
Next, thats all a journalist picks up, and it becomes a headline in the news.
Leo G (23:36:10) :
Yes, March 17, 1959 is when the picture was taken according to the US Navy. If you are seeking provenace, check out Time Magazine for 1959.
The Sun would be just below the Horizon and it would be dawn all day long.
The Brits have been playing up there almost as long as we have.
So, between the US Navy and Her Majestys’ Navy, there are a lot of vets sitting around cussing Arctic Melters.
I’m waiting for someone to approach a retired crew member screaming it was all a hoax seconds before receiving a Buzz Aldrin moment.
Antony, where is John Coleman’s latest film?
Have you already seen it?
[funny as that was we have rules against insulting other blog commenters ~ctm]
So to try to pull the bits together:
The North Atlantic ocean circulation patterns have changed resulting in warm subtropical water reaching Greenland where they have been implicated in increased glacier melt.
The ice arches did not form in the two straits alongside Greenland in 2007, resulting in the loss of Arctic ice.
With the extra thermal energy showing up around the Arctic area,
The Arctic Oscillation (AO) went strongly negative.
The snow line went south. The Northern Hemisphere snow extent shot up.
Oh, and the permafrost line went North.
Sort of seems like the extra thermal energy caused the AO pattern to “blow up” and spread diluted cold (less than Arctic normal) southward, as noticed during this NH winter. There are also longer term trends around the Arctic area that have been cited as evidence of global warming, but now look like they could be related to the ocean circulation changes and the subtropical warmth being distributed differently.
Also, hurricanes were way down, indicating the warmth that usually generates them was not there this year. Were the returning currents colder, having lost more heat than usual up North?
A large and complex system full of interesting interactions is slowly being revealed. And we are to accept this has all been accounted for in the CAGW models long ago?
Robert (22:32:54) :
Robert, you are exaggerating again.
Not going to do your math for you but, for one, you forgot your geometry. At pole max ~23.5 deg, you need to integrate over the cap for reflection. See a water refraction / reflection table in ref such as Handbook of Chemistry and Physics. For two, integrate for latitude, it’s not at ~23.5 for half of the year, now integrate that into correction one.
And 400 W/m^2? Maybe at the North Pole at exactly summer solstice and only at noon on a perfectly clear day. North Alaska in July only gets ~208 W/m^2 over a 24 hour period max. What, are you using Wikipedia again?
We don’t want to mislead here on WUWT if we can help it, do we?
And don’t feel alone, your fellow AGWers do it all the time.
http://polar.ncep.noaa.gov/seaice/hires/global.xml
(refreshed daily)
Note the huge rectangular area of sea ice
cut out of the sea ice by Canadian icebreakers
along the Labrador Newfoundland Quebec coasts–
Follow the red dots–they define this area.
The Canadaian icebreakers will be doing this
slicing of large blocks of sea ice repeatedly many times
over the next few months as the sea ice continues
to grow into the Labrador Sea–
I believe they do this to reduce the sea ice area
(to promote Canada’s AGW agenda) and also to enhance
the flushing effects of currents to clear the
northwest passage earlier and more easily and
thereby to continue to trumpet that canard.
Although this sea ice is probably less than 0.5 meter
in thickness, the continuous repetition of
the icebreakers deliberately slicing it will probably result in
the overall removal of at least 500 thousand
square kilometers of ice over the next few months–
thereby skewing ice measurements and
NW passage opening possibilities–
and has done so for at least the past 2 years–
So, to clear Hudson’s Bay and the NW Passage,
Nares Strait and others,
soon you will notice that
they will also be putting the
red dots from ice breakers into
Hudson’s bay over the next few months.
This sliced sea ice area also might
show up on some satellite photos
(but the red dots will not be in the photos).
Over the next few days you can observe this
current slab of sea ice
as it breaks up while being carried over to
the UK on the remnants of the Gulf Stream.
This type of large scale deliberate ice slicing by
Canada-USA icebreakers
has been ongoing for at least the past 2 years.
Save this link as a web page capture before it disappears.
Here we have to say:
http://3.bp.blogspot.com/_lD5nplPLYn4/S36hWwC_YVI/AAAAAAAAAYU/6OCDhIto63Q/s1600-h/image6189948x.jpg
“Robert (22:32:54) :
So . . . over 1.4% of the Earth’s surface (.014), for half the year (.5), you get the difference between .7 (120 W/m^2) and .08 albedo (368 W/m^2) (it’s 248 W/m^2). You get a total forcing of about 1.7 W/m^2.
That’s slightly more than the amount of forcing adding by all the anthropogenic CO2 added to the atmosphere to data, so it’s a potentially large source of positive feedback.”
And what effect does this exposing 7Msq Km of ocean surface have on loss of surface heat through latent heat of evaporation and convection? Which I’m sure would help in local cloud formation. And the increased Boltzmann radiation from the water’s surface vs ice. How much is that?
kadaka (03:49:04)
You’ve picked up on a number of important indicators there but have not sorted them into sequence to reveal the story.
The 2007 Arctic melt might have been stimulated by the failure of those ice arches but that was at the culmination of 30 years of positive PDO which peaked in 1998. It likely took until 2007 for that peak oceanic warmth in the Pacific to feed around the world to the Arctic. Clearly that also affected Greenland and contributed both to general slight warming of the troposphere and the northward movement of the permafrost boundary.
So far so good but the regime from 1975 to 2005 started to fade from the 1998 peak, jet streams had started to move back equatorward by 2000 and have slowly but erratically continued that movement since.
Now we have the strongly negative AO, generally cooling oceans despite the current El Nino and winter snows occurring in lower latitudes in both hemispheres.
Thus the warming of the earlier years does not seem to be the cause of the negative AO otherwise AO would have not been so persistently positive during the 30 year warming period from 1975 to 2005.
We have to look elsewhere for the cause of the negative AO and since the oceans didn’t do it from 1975 to 2005 I suggest we look up and not down.
Favourite candidate for me is a reduction in the rate of energy loss to space resulting in the current slight warming of the stratosphere which is contrary to the cooling stratosphere of the warming period. That warming of the stratosphere increases the power of the temperature inversion at the tropopause and leads to more intense polar high pressure systems which can then migrate equatorward across mid latitudes forcing the jets back equatorward even in the face of poleward pressure from the current El Nino.
That reduced rate of energy loss to space being associated with the contraction of the upper atmosphere caused by the quieter sun.
During the past warming spell the positive AO allowed faster ejection of oceanic warmth to space so that the warmth from those EL Ninos was not redirected downward in a negative AO.
Now that the rate of energy loss to space is less rapid the energy from the current El Nino was not ejected to space so efficiently and some was redirected downward to reinforce the negative AO that was already in place from the quieter sun.
Very recently, I have been comparing the DMI Polar Temperature plots with the slope of the curve on the Sea ice extent plots.
It seems to me that the DMI temperatures that jog above and below the 42 year daily mean plot predict the jogs in the slope slope of the extent curve. This might make sense especially in the winter when wind and currents may have less impact? Do the temperature readings cover enough area to be meaningful?
Am I imagining something or has anyone followed this possible connectivity for a longer period of time.