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Al Rodger

Something to watch out for next month will be the NSIDC Arctic Ice Extent for October.
The record for the lowest 12 months of Arctic Ice in the NSIDC data was set by May 2006-April 2007 with the 12 months Ice Extent averaging 10.666 million sq km.
The value is now approaching that mark. October 2010-September 2011 stood at 10.671. If as presently looks very likely, the Extent in October is lower than 7.6296 million sq km, then the record will be broken.


Very interesting, Al. Give a shout when this happens.

I'm not really sure if the effects of weather patterns after the melting season are very different from the ones during the melting season, but as Chris Biscan has mentioned here and there, all the forecasts are pointing to a Dipole Anomaly setting up, so that could slow down the SIE/SIA increase considerably.


On the AMSR-E front, Chris Biscan had this to report in another thread:

"Bremen saves the day:

and the tracking winter:


AMSR-E problems; maps not updated since Oct 4
The AMSR-E instrument has not produced data since Oct 4, 2011. Therefore, the sea ice maps cannot be updated. We are switching over to SSMIS data which might take a few days.

THey have already been saving these products for years.

The PSI-SSMI level 2 product contains, for both north and south poles, polar sterographic 12.5 km resolution grids of sea ice concentration from the 85 GHz channel of SSM/I on DMSP, available since 1992. The daily maps are processed from the daily brightness temperature maps from NSIDC. The Artist Sea Ice (ASI) algorithm developped at University of Bremen (Germany) is used to processed daily sea ice concentration maps at 12.5 km resolution. The dataset covers the whole 85 GHz SSM/I mission. We are grateful to NSIDC (Boulder, Colorado) for the SSMI data.

That is the gist of it.

The SSMI is really no worse at this point than AMSRE, except weaker resolution. Since Jaxa was doing 25km grid res converted to 12.5km2 grid res for main products. Bremen having 12.5 grid res maybe converted to 6.25km for the winter with SSMI is great IMO."

I just saw on the IJIS website (probably was there longer):

"Sea-ice data update stops for a while due to the suspension of AMSR-E observation."


The Polar Vortex...
As I understood, that vortex is located near and above the tropopause. It has a cyclonic low pressure, which doesn’t necessarily have to push down to the lower troposphere. On the contrary, it was over strong low level highs during periods of negative AO. The vortex may hold the very cold airmass together there, but that doesn’t have to apply for the 850 MB level, too. As Adelady expressed very well, the rise of the strong vortex had much to do with anomalously high tropospheric bulges earlier that winter. These bulges strengthened the negative AO, leading to cold outbreaks in Europe and the States. Wayne Davidson has explained the high troposphere cooled later in the season, born contradictory out of the late fall warmth. That cooling got down over the Archipelago and Baffin Region, finally creating very cold weather over there. But the Siberian side remained anomalously warm on the low level.

Kevin O'Neill

I grew up on a body of water that rarely freezes over, but always has thousands of square kilometers of ice in winter; Lake Superior. As you get older you sometimes find yourself becoming a caricature - i.e., when I was young the winters were colder, snows were deeper, yadda, yadda, yadda. Yeah, whatever grandpa.

So I always find a little personal solace when I run across information that confirms my anecdotal recollections. Visiting one of our National Parks websites I found this (just 60 miles from where I grew up):

In Bayfield, Wisconsin, between 1857 and 2007, the onset of ice cover occurred an average of 1.6 days later per decade, and break-up of ice cover has occurred an average of 1.7 days earlier per decade due to rising air and water temperatures. Taken together, these changes have resulted in an approximately 3-day per decade (45 days over 150 years) reduction in the ice cover period. The most significant changes influencing this average occurred since 1975, with the ice season beginning an average of 1.7 days later and ending 3.0 days earlier every decade (Howk 2009).

It's GLOBAL warming. It's not limited to the arctic. And the snows *were* deeper and the winters *were* colder when I was young :)

Here's Lake Superior in winter 2008.

Andrew Xnn

Be careful about Global Warming and the impact snowfall.

In many places (including the Great Lakes) warmer temperatures result in more snow.

“Recent increases in the water temperature of the Great Lakes are consistent with global warming,” said Burnett. “Such increases widen the gap between water temperature and air temperature – the ideal condition for snowfall."


In addition, the IPCC has also noted that for the Northern Hemisphere there is a trend towards more snow in November and December; due to Global Warming.

Daniel Bailey

@ Kevin

You might be interested in this, then:

Temporal and spatial variability of Great Lakes ice cover, 1973–2010
Jia Wang, Xuezhi Bai, Haohuo Hu, Anne Clites, Marie Colton, and Brent Lofgren

    "In this study, temporal and spatial variability of ice cover in the Great Lakes are investigated using historical satellite measurements from 1973 to 2010. The seasonal cycle of ice cover was constructed for all the lakes including Lake St. Clair.

    A unique feature found in the seasonal cycle is that the standard deviations (i.e., variability) of ice cover are larger than the climatological means for each lake. This indicates that Great Lakes ice cover experiences large variability in response to predominant natural climate forcing and has poor predictability. Spectral analysis shows that lake ice has both quasi-decadal and interannual periodicities of ~8 years and ~4 years.

    There was a significant downward trend in ice coverage from 1973 to the present for all the lakes, with Lake Ontario having the largest, and Lakes Erie and St. Clair having the smallest. The translated total loss in lake ice over the entire 38-year record varies from 37% in Lake St. Clair (least) to 88% in Lake Ontario (most). The total loss for overall Great Lakes ice coverage is 71%, while Lake Superior places second with a 79% loss.

    An EOF (empirical orthogonal function) analysis indicates that a major response of ice cover to atmospheric forcing is in phase in all six lakes, accounting for 80.8% of the total variance. The second mode shows an out-of-phase spatial variability between the upper lakes and lower lakes, accounting for 10.7% of the total variance.

    The regression of the first EOF-mode time series to sea level pressure, surface air temperature, and surface wind shows that lake ice mainly responds to the combined AO (Arctic Oscillation) and ENSO (El Nino and Southern Oscillation) patterns."

Last nite we went through about 8 years of old family 8mm tapes from the 50's & 60's. It was amazing to see how much more snow there was then in the UP (and ice on Lake Superior) than exists today.

Kevin O'Neill

Daniel - Thanks! One of the articles I read recently mentioned that Lake Superior could be ice-free by 2040. Sound familiar?


Kevin McKinney

Growing up on the shoresof Lake Superior--well, *nearly* on them, Sault Ste. Marie is on shores of the St. Mary's River--we were well aware of the effects of a frozen vs. unfrozen Lake.

Lake effect snow has a pretty direct effect on everyday life, after all. So "Snow Ste. Marie" may live up to its nickname more in the 2040's--though with warmer temps, we won't see the towering drifts I recall from the early 60s, even if amounts of total snowfall increase, compaction and melting will probably more than compensate.

Wayne Kernochan

OK, I can't resist :)


Has anyone noted that, according to the 10/5 NSIDC arctic concentration map, the Northwest Passage is now open again, and therefore both that and the Northern Sea Route are once again open?

Also, the Gulf of Bothnia, on about the same latitude as the northern tip of Scotland, is busy icing up, while there's open water all the way well into the 80s in latitude above Norway.

Meanwhile, in the Antarctic, high temp anomalies averaging about 20F seem to be continuing on land, while sea ice area has moved into positive anomaly for a sustained period for the first time this year. This appears to be similar to the pattern last year, and I would expect it to dip into negative anomaly again by December. I think, however, that we have about run out of time for a new global area anomaly record for this year.


Hi Waine...
Ice in the Gulf of Bothnia? For the sake of thoroughness, I checked MODIS. There is none. The NSIDC map should only be taken serious on the Central Pack. There is no ice in Cheskhkaya Gulf, not in Baydaradskaya Bay, nor in the Ob-estuary or Khatanga Bay. I often wondered why the NSIDC responsible would allow the map to be flawed by nonsense ice cover like in the Gulf of Finland?
It doesn’t relate to an American approach, because there is no ice on Coronation Gulf, too.


Taking it to the open thread...
First year ice doesn’t matter… even when it’s formed to it’s max thickness during wintertime, it won’t pass 1,8 m in thickness. As clearly explained in our posts, the briny FIY melts out easily. Once the MYI has virtually vanished, and SST’s have exceeded -1.7 degrees over large parts of the Central Arctic, it can be over in a flash during a supportive summer.
There are other data hinting at this possibility. The area of less than -1.7 degrees SST has shrunk considerably. Less than 10 years ago, the Northern Kara Sea and most of the Beaufort Sea were firmly bound within these low SST’s. They’re not, anymore. This is what’s going to happen to the Central Arctic too, soon. The process is already in motion. On close view, the Central pack is run through with leads filled with rubble. Between them, only 35% consists of integer floes. And they’re not easily found! The Polarstern crew had a hard time finding the right ones for their experiments.
I respect the view of FI Bob Wallace, who IMO holds a truly scientific approach to what can be learned on the state of the Arctic. His, though very isolated, remark on the freeboard of the floes in the East Siberian Sea is undisputed. It could be the remaining floes there made for a higher average thickness than 0,4 m. It is right time to gather all buoy-, airplane-, vessel-data to get the thickness dispute in any comprehensible format.
My suspicious feeling on the climate models is fed by multiple perceptions:
- Most models have biases...the behaviour of evaporation/convection/ clouds is the main difficulty
- The first Cryosat attempt, which was premature...
- Well-informed scientists seeing no evidence for tipping points, like just three months before the 2007 downfall (allright, it’s only noise???)
On a philosophic level: what can be measured? The past, yes, but modelling the future out of there is comfortably conservative... Hamilton’s , Wipneus’ and Frank D's curves give a good sense of urgency.
On politics: there are convincing arguments not to support panic. Let the wise please hold some truth hidden for the unfortunate, to make their spare time as comfortable as possible. In the meantime, a lot of ‘science’ is funded through ‘big oil’.


Actually, as an interested observer I have to comment that the scientific community does not look very wise and authoritative about now. 5 short years ago they were publishing 2070 or so as the probable date of an ice free arctic. They backed this up with all of their sophisticated computer models. The simplest trend analysis shows the loss rate is accelerating and the ice is unlikely to last 20 years even without acceleration. OOPS our model was off by 50 years? And of course there is the scientific noise such as even if all the ice is removed it will fully recover in 2 years. The next IPCC report is due out soon. The question for the scientific community is do they continue with the long time horizon prediction of their models when the ice may very well melt out within a couple of years of the report release or are they going to start saying we were wrong the ice is almost gone right now. We have just started to see the papers saying wow it looks like we don't have even until 2040.
AND this may be much too conservative.

Bob Wallace

" if all the ice is removed it will fully recover in 2 years"

I don't think this is what was said. More accurately I remember the statement to be that even after a complete melt out we could experience one or more cold years which would result in some year round ice. Not a complete 3+ meter recovery.

And that was further softened by saying that a temporary recovery would be, temporary.

Overall, just an argument that there is not necessarily an absolute point of no return. Noise is possible.

Now, as to conservative predictions. It seems to me that climate scientists have been under tremendous pressure aimed largely at suppressing the message/killing the messenger. Given the risk I would suspect that scientists would tend to present the 'least bad' case in order to not have to defend the worst case in a hostile environment.

The IPCC is, I believe, a much more politically influenced report than would be a summary statement coming out of a climate scientist's lab. Look at the statements that Hansen has made, you'll find them a lot less 'diplomatic'.

Bob Wallace

Runin - you might want to read this article (I just did after my previous post)...

On the difference between predicted and observed ice melt...

" This can now be explained by ice thinning, which has accelerated. Sea ice has become thinner and more fragile.

Because it breaks up more easily, its mobility is increased, as is its export from the Arctic Ocean through the Fram Strait between Greenland and the Svalbard archipelago, followed by its melting.

This mechanism may be exacerbating the present decline in Arctic sea ice."


(Thanks, Nevin, for putting interesting links in the upper right of the page.)

Daniel Bailey

Rampal et al 2011 can be found here:


Chris Biscan

the NW passage has never come close to closing yet.

I am not trying to be a jerk about it..but it hasn't.


Anyone else see the Science Daily report on the return of the Polarstern?

Huge surprise! The ice is young and thin instead of old and bulky. Who'da thunk it.


And wow! just wow.

Brilliant animation of the Beaufort gyre from 87 through to the middle of this year. Great commentary too. Hadn't thought of that before - the gyre is now the enemy of the ice rather than the beneficent force that once held it all together.


Adelady, the press release from AWI has another interesting tidbit. My translation:

Scientists found clear discrepancies [between 2011 and 2007] in areas where ice was absent this summer, for example in the Laptev Sea.

„On our expedition in 2007 we already encountered thin, newly frozen ice in the Laptev Sea in September. This year there were no signs of freezing to be found anywhere. The water temperature 10 meters down was 3 degrees C - that's how much the Sun had warmed the ice-free sea surface“, says Prof. Dr. Ursula Schauer.


Hmmm. Rampal et al 2011
"Models underestimate the observed thinning trend by almost a factor 4 on average, i.e. in a way even more spectacular than they do for the sea ice extent decline. This underestimation of the thinning trend cannot be explained entirely by an underestimation of the decline of the perennial, thicker, ice-covered portion of the Arctic." &
"Therefore, this strong underestimation of sea ice thinning and drift acceleration in models would imply that former projections for an ice-free summer in the Arctic by 2100, based only on the comparison of simulated and observed sea ice extent reduction rates [Arzel et al., 2006; J. L. Boe et al., 2009], are too conservative. This is reinforced by the fact that the current thinning trend is more than 40 years ahead of the ensemble mean forecast whereas the fraction of the ocean covered by ice is highly sensitive to ice thickness changes."

Physorg report
"They argue that climate models underestimate the rate of ice thinning, which is actually about four times faster than calculations." &
"When this mechanism was taken into account to correct the discrepancy between simulations and observations, results from the new model suggested that there will be no Arctic sea ice in summer by the end of the century."

Usually you find reporting of papers hyping up what a paper says. It seems to me that Physorg is rather downplaying this paper's implications.

Peter Ellis

Chris B: It depends which Northwest Passage you're talking about. The main deep Parry channel, although it looked ice-free on most of the satellite maps, barely opened at all this summer. Although the ice was at record low levels, there was still a narrow strip of lower concentration ice that posed a hazard to shipping, and the passage was not declared open.

Don't take my word for it, take the NSIDC's.

"Overall, sea ice in the wider and deeper northern route through Parry Channel reached a record low, according to Stephen Howell of Environment Canada, based on Canadian Ice Service analysis. Parry Channel had a narrow strip of ice that blocked a short section of the channel, but it did appear to open briefly in early September."

I posted about this before, in the Bremen/Jaxa/MASIE/NSIDC discussion, with links to the Canadian Ice Service site.

Basically, SSM/I is known to be less effective at picking up thin ice, so the Parry channel appeared open even when it wasn't. AMSR-E is (was) better at detecting this type of ice, so Jaxa correctly showed the channel as closed. For some reason, Bremen's algorithm didn't pick up the blockage, so I suspect they also underestimate thin/low concentration ice. MASIE is not based only on microwave data but also on visual data (and radar? Not sure), and they correctly showed the Parry channel as closed.

The more southerly Amundsen channel did indeed open for a substantial chunk of the season.


>>"if all the ice is removed it will fully recover in 2 years"

>"I don't think this is what was said. More accurately I remember the statement to be that even after a complete melt out we could experience one or more cold years which would result in some year round ice. Not a complete 3+ meter recovery.

And that was further softened by saying that a temporary recovery would be, temporary."

To clarify, see

for discussion of Tietsche et al., and fig 3 explanation in particular:

"Figure 3: Evolution of September sea-ice extent in coupled climate model simulations. The blue curve shows the evolution of the unperturbed sea-ice extent for the A1B scenario, with the gray shading showing the ensemble spread of three model runs. For the red curves, sea ice was artificially removed at the beginning of June in 1980, 2000, 2020, 2040 and 2060 within the climate model simulations. For all these perturbations, sea-ice extent recovered rapidly to the unperturbed extent. A similar result was found for sea-ice volume."

So both extent and volume recover to equilibrium level typically by about 2 years after removal. If extent and volume are fully recovering then thickness has to be fully recovering as well. So it is a full thickness recovery but only to equilibrium level for relevant time & forcings. It isn't full recovery to 1980 thicknesses.

This tells us the typical lag from a major event is 2 years at most. However, it doesn't tell us how quickly the equilibrim level is changing with time.

William Connolley was (3rd?) author on a similar paper which also showed full thickness recovery within 2 year but I think that only worked on past conditions not at several different future dates.

Bob Wallace

From the Science Daily/Polarstern article...

"One-year-old ice, by contrast, is more pervious to light, especially in areas with many melt ponds. The researchers measured the greatest amounts of light under new ice. "From these results we can conclude that the observed change from a several-year-old ice cover to a seasonal Arctic ice cover will lead to an increase in light in the Arctic Ocean, particularly in summer and autumn," "

More light through, that means less albedo from first year ice, more heat forming under the ice, and probably more algae growth.

That's one more accelerating factor.


Robert Grumbine has a good post on consequences of the AMSR-E failure.


Interesting news on the albedo front: our Finnish friends have found a way to estimate albedo numbers using a microwave-based method (I hope they're not dependent on AMSR-E).

When compared against the conventional optical method, the microwave-based method for estimating albedo has the advantage that neither cloudiness nor the low Sun angle in the Arctic region interfere with the measurements. For instance, it is possible to detect whether spring is coming unusually early; this is something that optical instruments do not necessarily reveal at that time of year.

Science Daily


Amazing what’s new without the AMSR-e input.
Reading between the lines of the initial ‘final’ media release from AWI-Polarstern I feel support for the pessimist view on thickness/volume. I’d crave for their data; ‘only in the Canadian Basin and near Severnaya Zemlya we found thick MYI 2-5 m thick ice’.
Now how could one calculate on that? First, I’m surprised they mention Severnaya Zemlya. Just days ago, NSIDC published an age-graphic showing a thin MYI arm from Ellesmere to Zemlya Novaya Sibirskaya (I love the language...). The demise of the ‘Taymir-connection’ was one of the remarkable developments this year. My guess is, their long search for the right floes was sparsely rewarded there... I can imagine they found more around the Canadian Basin. To be specific, in a ‘one million’ square km’s 500 km to the NW of Ellesmere. That’s where the Healy gave the lead to the Canadian icebreaker.
Remember the awesome webcam images? I had a flashback to this great painted image by John Turner: ‘last voyage of the HMS Temeraire’(1831). It had the same sad reminiscence of change that’s going nowhere. We just shouldn’t be there, at least not ‘in der Rote Salon bei Kaffee und Kuchen’ as if you’re in a Munich ‘Kneipe’ while you’re actually passing the North Pole... (one of the photo's on the reports)
The Temeraire... the steam tug is as ugly as our licking, respectless approach to our environment. The sailboat is in all it’s romantic splendidness like human endeavour as it could have remained... without the damned fossil fuel economy.Photobucket
Finally... it’s quite clear where this is going. And while our means to be sure on data fail like dimming candlelight, we can only rely on morality?


Bob Wallace
Some quotes from the paper are in order.
"The model setup we use is a coarse resolution version of the IPCC!AR4 model described by Jungclaus et al. [2006]. This higher resolution model setup has been tested extensively and performs well in simulating Arctic climate [Chapman and Walsh, 2007]."
WAIT A MINUTE? How does the low resolution model they used perform at simulating the artic climate? They do not justify in the paper the performance of the model they use. Another quote from the paper "We find that ice extent recovers typically within two years." So they do basically claim that the ice recovers in 2 years. "Our results suggest that anomalous loss of arctic sea ice during a single summer is reversible, as the ice–albedo feedback is alleviated by large scale recovery mechanisms. Hence, hysteretic threshold behavior (or a “tipping point”) is unlikely to occur during the decline of Arctic summer sea ice cover in the 21st century." To be fair their model predits that the ice extent will decline below 4.5MsqKm sometime after 2020 and then decline to 2MsqKm rapidly over the next 20 years. Then it takes 30 more years to decline to ice free conditions. They assert that even if an entire summer is ice free the extra heat will all radiate away by the end of Nov.
The whole study reads like a set up to me. The outcome was predetermined when they selected which model to use.


Bob Wallace
Sorry I addressed my previous post to you when it should have been crandles. His comment that they did not say the ice recovers in 2 years is what sparked me to write the above post. Not your execellent commentary.

Kevin O'Neill

RunInCircles: They didn't say the *ice* recovers. They said *ice extent* recovers. That can be a pretty significant difference.


You can actually read the paper. Look it up on the web. They said the ice recovers not just the extent.

Daniel Bailey

@ RunInCircles

Per Tietsche et al 2011:

    "We find that ice extent recovers typically within two years."
Perhaps a more thorough read of the paper is in order...

Kevin O'Neill

RunInCircles - I've written about the Tietsche paper here and other places. I've read it and reread it. I don't have access to the auxillary materials where they may expound a little more on volume.

What I took away from the paper (stated more eloquently by Chris R over on his blog) is that the extra heat gained by removing the ice is quickly disassociated from the system. Very little memory of it can be found in subsequent years.

That said, it has to be kept in mind that we have not recovered to pre-2007 levels within the specified 2 to 5 years. Again, they predicted extent recovery within 2 to 5 years of removing all summer ice on July 1st; yet we haven't even seen a "recovery" after removing merely a moderately large fraction of it (2007).

Additionally, they were using an IPCC AR4 model; all the AR4 models underestimated ice extent, area, and volume losses. The AR4 models all had a conservative bias.

I think Rampal et al highlight the most obvious reason for understating the ice loss in the IPCC AR4 models: a lack of well-parameterized ice mechanics and kinematics. A thinner, fractured ice-pack reacts differently than a homogenous slab.

There are also issues with the parameterization of the ocean currents beneath the ice (Ron Kwok has several papers in this regard). And there are known problems with the IPCC AR4 cloud parameterizations over newly ice-free seas (Kay et al.

All of these appear to have contributed a bias in one direction - leading to the underestimation of sea ice losses. When these parameters are modeled and initialized correctly we *will* see different results. Now, whether those results are significantly different is anyone's guess, but we *know* the model used was unable to predict the current state of the arctic.

Note: There's no denying the large negative feedbacks highlighted by Tietsche et al associated with large extent or area losses. What appears to be the observational case is that the positive feedbacks outweigh the negative feedbacks.

Rob Dekker

Great discussion guys, especially on the balance between negative and positive feedbacks, and Tietsche et al.

For starters, the "ice recovery in 2 years" result by Tietsche et al relies on a strong negative feedback caused by increased IR emitted during the fall (of ~0 C open ocean versus ice with an atmosphere far below freezing).

Against this negative feedback, there are positive feedbacks. Albedo feedback and polar amplification are the most obvious ones, and all climate models include the physics for these.

However, it seems that every year we find another positive feedback of some sort, and it seems that positive feedbacks of first year ice (such as increase dynamics, increased cracking, lower melting temp, decreased albedo, increase lead/melting pond formation, de-stratification due to increased salt-rejection etc etc).

Model developers have a very hard time keeping up with all these non-linear (and hard to quantify) positive feedback effects, so it should come as no surprise that most models under-estimate positive feedbacks in the Arctic.

So the 'recovery' noted by Tietsche et al may very well be just reflect the deficiency of GCMs to model the complex behavior of (especially thin) sea ice, rather than an accurate reflection of reality.

The decline of ice extent as well as volume is still following a 'quadratic' curve, which suggest that positive feedbacks are still winning and we are still in the first part of the Gompertz curve.

The question is WHEN (in sea ice extent and in timing) will the take-over happen ?

Rob Dekker

To answer my own question, I think that sea ice decline will approximately follow the Gompertz curve projected by the IPCC GCMs
but because positive feedbacks are underestimated in GCMs, this scenario will simply work out much faster than we imagined.

In other words, the Arctic is probably much more sensitive to (global) climate change than we anticipated.

Which makes me wonder which other parts of the Cryosphere may be much more sensitive to climate change than we anticipated...

Artful Dodger

Neven, the Journal article reveals that microwave albedo measurement was based on AMSR-E data. See:

Laine et.al (2011) "Shortwave broadband black‐sky surface albedo estimation for Arctic sea ice using passive microwave radiometer data" in JGR - Atmospheres.

This research analyzed the correspondence between optical albedo (AVHRR) and microwave brightness temperature (AMSR‐E)

So, not quite S.O.L. since there are other microwave sensors in orbit, but the work would have to be redone to calibrate the new sensor to AVHRR.


Al Rodger

With all the comment on ice loss and whether there is a tipping point (ie is the system strongly hysteretical? - RunInCircles, I like that word!)one factor I have not hear mention of directly is Latent Heat.

PIOMAS shows annual ice loss of +500 cu km. GRACE shows a similar value for ice loss in Greenland. That's a lot of ice to melt. Very very roughly then, the Arctic is using 0.4 zetaJoules per annum to melt all that ice. Put in context, Ocean Heat Content is rising at about 3 to 4 zetaJoules per annum.
If models are greatly underestimating ice loss, they must also be underestimating the heat that will remain in the Arctic if that ice loss were to cease.


Rob Decker wrote:
Which makes me wonder which other parts of the Cryosphere may be much more sensitive to climate change than we anticipated...

Now it's almost 2am, and you've given me even more reason to have trouble falling asleep!


From Tietsche et al 2011
"September sea ice volume takes longer to
recover in the late 20th century when the sea ice is still thick, but it has the same time scale of recovery as sea ice extent from 2000 on"
The measure of recovery used is extent but they assert that this is a proxy for complete recovery even volume. I was not sure if your post was scolding me for not recognising that their direct 1st paragragh executive summary statement used the word extent. Do you think they drew a distinction between ice extent recovery and ice recovery?
@ Rob and Kevin thanks for giving me more homework! I trully do not know as much as I would like to. Your pointing out additional sources to go learn from is invaluable to me.
@Al Rodger :Artful Dodger posted a link to a paper which showed strong hysteresis behavior based on ice physics alone. That link was posted within the last month.


Runincircles wrote
"Bob Wallace
Sorry I addressed my previous post to you when it should have been crandles. His comment that they did not say the ice recovers in 2 years is what sparked me to write the above post. Not your execellent commentary."

I think you were right the first time, Bob Wallace did write
"I don't think this is what was said. More accurately I remember the statement to be that even after a complete melt out we could experience one or more cold years which would result in some year round ice. Not a complete 3+ meter recovery.

And that was further softened by saying that a temporary recovery would be, temporary."

I quoted that to indicate that was what sparked me to write my attempted clarification that Tietsche et al do claim volume does fully recover in 2 years but that full recovery is to equilibrium level not back to 1980s' or 3m+ thicknesses.

Bob Wallace

I spent some time last night reading the long comment section on the Real Climate piece linked below.

A couple of things stuck with me and I wonder if anyone has a comment on them.

First, the winds of 2007 were strong but they weren't abnormal. They were within the normal range of what has been happening in the Arctic, it's just that strong-normal wind acted on record thin ice.

Since average thickness in 2011 was roughly 50% of the 2007 level that suggests another year of strong-normal wind could be "interesting". It wouldn't take an abnormal/unique wind year.

Second, while sea ice extent hasn't changed much since 2007 there has been a noticeable loss of land ice. This was seen in the loss of small glaciers.

I would assume the loss of land ice, close to the beach, would be another amplifying force and might contribute to the breaking loose of fast ice. Were the ice along the east coast of Greenland to break free I would think it would soon drift into water where it would rapidly melt and that fast ice would be very unlikely to reform.


Chris Biscan

12Z GFS is terribly ugly for MY ice loss...just about as bad as it can be this time of year. This is the worst time for it...pressures are low enough to create much more powerful winds then seen in summer. And the ice is still very thin..which means it can move faster than it would in dead winter. On top of that the Western Arctic Basin is still open water and the mean flow will be one of compaction drawing warm air in for 10 days at least.



I am not sure how much this will slow down the extent gains...but it will likely put us near 2007 by the 15th-20th if it pans out. However more damaging again is where the MY ice is and how fast it can move.

Models are forecasting 40-50Kt surface winds off the east coast of Greenland by tomorrow afternoon.

Artful Dodger

Hi Bob W,

The 2007 sea ice retreat was made exceptional by warm water inflow from the Pacific to the Arctic. Tethered Buoys in the Bering Strait measured ~4 petajoules of heat entering the Chukchi sea. This is twice the normal heat influx, and equal to total solar insolation for the Chukchi sea over the course of the melt season.

Look at the distribution of sea ice throughout summer 2007. There is a clear focal point to the melt, the source of the heat bloom is the Bering Strait.

This paper provides more details (the AGU introduction is provided 2nd below):

RA Woodgate & T Weingartner (2008) "The 2007 Bering Strait Oceanic Heat Flux and anomalous Arctic Sea-ice Retreat", Geophysical Research Letters

AGU: "Heat from Pacific stoked Arctic melting"

"The causes of the 2007 record-breaking Arctic sea ice loss are not well understood. To investigate the source of the heat that melted so much ice, Woodgate et al. study the role of heat transported to the Arctic from the Pacific Ocean. The authors use observations from in situ moorings and satellite sea surface temperature measurements to quantify the heat flux through the Bering Strait into the Arctic. They find that a substantial amount of heat is transferred through the Bering Strait and that this amount is highly variable from year to year. In 2007, both the amount of water flowing through the strait and the temperatures were at record highs, the authors report. They note that the 2007 heat flux through the Bering Strait was twice the 2001 heat flux and was enough to account for a third of the Arctic sea ice lost in 2007."

What I have not seen yet is any discussion as to the cause of the exceptional heat transport in 2007. I wonder if it was associated with the strong El Nino that year? If so, is this a common pattern for other El Nino years, and should we expect a recurrence during the next El Nino?

Given the weak state of Arctic sea ice in 2011, and the near total loss of MY sea ice, another +4 PW Summer heat influx from the Bering strait could well spell the first ice-free Fall.

Artful Dodger

Pardon, the paper above should be cited properly as:

Woodgate, R. A., T. Weingartner, and R. Lindsay (2010), The 2007 Bering Strait oceanic heat flux and anomalous Arctic sea-ice retreat, Geophys. Res. Lett., 37, L01602, doi:10.1029/2009GL041621.


Bob Wallace

Thanks for that Artful. Hopefully I'll get up to speed on all this stuff before the first melt-out.

(I may need a Crump schedule to get there...:(

Wayne Kernochan

@Artful Dodger: Naive question. I understand from MIT's book "Fate of Greenland" that a deep-sea current starts with Gulf Stream waters diving down near Greenland, flowing south to the Antarctic and then 1/2 way around the world, then flows north and resurfaces near the Bering Strait. Is it possible that the unusual heat influx partially reflects unusually warm Gulf Stream waters from several years previous?

Btw, I think that Hansen is in accord with the "connection with El Nino" idea, as I believe he has been quoted as saying that he expects a significant increase in melt in 2012, because (at the time he said this) 2012 was likely to be an El Nino year.

Artful Dodger

Hi Wayne,

Interesting concept, beyond my knowledge though ;^).

I have a faint memory engram of an experiment on deep ocean circulation conducted with some sort of marker dye. Wait one... oh yes, here it is:

W. Maslowski et.al (2000), Modeling Recent Climate Variability in the Arctic Ocean, Geophysical Research Letters.

I see what Dr. Maslowski has done is to create "virtual dyes" for water of different temp/salinity, so that its source can be traced visually in the model.

However, the authors used a limited-domain coupled Arctic Ocean and sea ice general circulation model. Their Model Description says "The rotated numerical grid covers the Arctic Ocean, the sub-polar seas and the North Atlantic to pproximately 50 N. The Bering Strait is closed."

So this is not quite on the scale that you describe. Still, they found some interesting results:

In 1979, the Beaufort Gyre extends over the entire Canadian Basin and the Transpolar Drift is positioned along the Laptev Sea - Fram Strait axis. In the 1990s the Beaufort Gyre becomes much smaller and it is con fined mostly within the Beaufort Sea. This change is associated with an eastward deflection of the Transpolar Drift, to the northern boundary of the Beaufort Sea.

Maslowski's limited model predicted this over 11 years ago! We have certainly seen these events occur over the last few years. Amazing stuff, that Science!

Chris Biscan

00z GFS has a DPA threw 180 hours..cripes...


MASIE numbers are all over the place right now. 3 days of extend loss followed by over 300,000 increase in 24 hours.

interesting times!


@ Al Rodger

I'd like to make a quick correction to the very first post on this thread. (I've been painting garden furniture for a few days - hence I've only seen this today!)

The all time rolling 12 month low (thus far) was from November 2006 - October 2007, and not May '06 - April '07 as suggested. I had pointed out a few weeks back that October 2007 had had a huge impact upon the yearly averages, and I could not understand how this wouldn't feature in the lowest rolling-12.

As Al rightly points out, the NSIDC figure for October could well produce a new record low - the magic number to look for next month will be 7.5 million sq km. Anything below that, and it's a new rolling-12 month low. That equates to 190,000 sq km less than October 2010, with the September average for this year already 290,000 sq km down on last year.

The JAXA figures (if/when they start again) are less likely to produce a record. They would need to average about 670,000 sq km below last year, but were standing only about 550,000 down when the system went tits-up.

Al Rodger

Yes, thanks BilltheillFrog. Absoulutely correct. I managed to trip over my own spreadsheets. It's the year 'centred' on April 2007, not ending April 2007.


@ Al Rodger,

Dammit, you've got me started. Here are some more snippets...

From the 1st January 2000, the Cryosphere Today Arctic Sea Ice Area shows approximately 95.1% of the days with a -ve anomaly.

The last time there was a +ve anomaly with the CT Arctic Area was (if my sums are right) on the 11th December 2004. That single day was the only excursion into +ve territory since 4th April 2003. In other words, one day in the last 8 and a half years.

The year-to-date CT Arctic Area anomaly is 37,000 sq km below the 2007 equivalent as at day 279 - or the 6th Oct. The Area as at that date is about 500,000 sq km above its 2007 equivalent. However, 2007 started to refreeze big time in the second half of this month. It could go either way, but I think 2011 will end up with the second lowest annual average for Arctic Area.

Moving on to CT Global Area, 76.3% of the time since 1st Jan 2000 has been in the negative anomaly zone. Since 1st Jan 2008 the figure rises to nearly 82%, since 2009 it's at 87% and is at 95% since the beginning of 2010.

The record number of consecutive days with a -ve Global Area anomaly is currently 445 days, with the run ending around the 8th December 2007. As at day 278 (5th October) the present run stands at 414 days - easily the second longest run thus far. The anomaly as at this date is -1.666 million sq km, and should this remain in negative territory past the 5th November, that would constitute a new record sequence.

The Global Area anomaly as at this date in 2007 was 7,000 sq km lower than at present, but the year to date figure for 2011 is about 182,000 sq km lower than for 2007. Therefore, as long as the average anomaly for the remaining 87 days is less than +582,000 sq km (a very serious swing away from the present numbers) then 2011 will end up with the lowest annual average for Global Sea Ice Area.

In terms of a rolling 365-day average of the CT Global Area, 2011 has already clocked up the 6 lowest figures on record. These occurred between the 14th to 19th September.

Out of the 100 lowest rolling 365-day averages, 49 were in 2007 with the rest occurring this year. As the first of these 51/100 only happened 51 days ago, and the latest is at position 36, it is highly probable that 2011 will accrue further entries in the top (bottom?) 100.

The distribution across the 100 lowest rolling 365's is also skewed. 2011 has 7 in the lowest 10, while 2007 has 7 in the 91-100 range. Who knows what the split will be by the end of the year?

I'm sure I'm not the only one who finds these numbers rather scary.

Cheers Bill F


The only one who finds these numbers rather scary?

I had a quick look at those Cryosphere numbers a couple of days ago. And decided I really didn't need to look at any more.


Quite a dipole at the moment:

What a shame we lost IJIS SIE! Now we can't see the change, if any.


Hi Neven et al,

Dr Jeff Masters has written a good piece on his wunderblog about the Arctic Ozone hole, reposted at Climate Progress.

The recent Russian impromptu expedition to investigate methane emissions is not due to report properly until the end of October, but there is now a little bit of press, suggesting they are indeed finding large emissions of methane - which one of their number rather bizarrely describes as being caused by entirely natural seismic activity.


things really are happening right now.
one million KM^2 increase in extent on MAISE in the last 10 days and half of that was in the last 24 hours or so.
And MODIS is close to being worthless at the moment. Anyone know why there is a daily 1000km diameter hole in the observations right now.

Al Rodger

I've been reading the paper linked in the Artful Dodger post above (ie RA Woodgate & T Weingartner (2008) "The 2007 Bering Strait Oceanic Heat Flux and anomalous Arctic Sea-ice Retreat", Geophysical Research Letters - http://psc.apl.washington.edu/HLD/Bstrait/Woodgateetal_2007BStraitHeat_GRLrevNov09forweb.pdf
) & while it contains some interesting stuff, its abstract is far from clear (or correct).
The paper is looking at heat transport via the Bering Straits into the Arctic for the years 1991 to 2007. Figure 2e shows totals for years 2000 to 2007 & Figure 3 shows the timing of the flux through some years 2001-7. Water temperatures, timings & variability feature in the discussion but the size of this heating is perhaps the headline readers will take away.

They say the Bering waters supplied roughly 0.3 zJ in 2001 & 0.6 zJ in 2007. (z = zeta = 10^21). While 2007 was the largest figure, fig 2e shows 2001 was a minimum & a gradual rise from then to 2007, so the flux in 2007 was not as exceptional as all that.
As for the significance of the flux, they point out that 0.3 (0.6) zJ could melt 1 (2) million sq km of 1 metre thick ice. They go on to suggest the 2 million sq km would equate to 1/3 of the total reduction of Ice Extent during a melt season but this is wrong - it would be 1/5. Further, in terms of volume, the PIOMAS model gives the volume melted during a season as some 17,000 cu km which would require 5.7 zJ to melt, about ten times the Bering Straits 2007 flux.
Although less that the paper states, these figures show Bering Srait heat is a big factor in the Arctic melt season and as the paper says, this heat may well also cause amplifying ice-albedo feedbacks.


And MODIS is close to being worthless at the moment. Anyone know why there is a daily 1000km diameter hole in the observations right now.

Philiponfire, that's because there's not enough light there for the sensor to pick up. This occurs every year. Or see this post at the beginning of the melting season that shows the white hole getting smaller again.

Andrew Xnn

Found the following time series graph from the Woodgate Paper of heat flux thru the Bering Strait:

Notice, that while 2007 had the largest heat flux, 2004 was about the same while 2001 was exceptionally small.

With respect to El Nino/La Nina, here is a graphical time series of Pacific Equatorial Temperature anomalies:

Can't really see 2004 and 2007 standing out with much warmth.

Kevin O'Neill

philliponfire - the MASIE number for 10/09/2011 is 5.6 km^2. This is right where we should expect it to be. If you look back in the IJIS dataset for 09 Oct

  • 2006 6.5
  • 2007 5.2
  • 2008 6.3
  • 2009 6.1
  • 2010 6.3

Above 2007, but significantly below all other years.


Notice, that while 2007 had the largest heat flux, 2004 was about the same while 2001 was exceptionally small.

Is there any data for post 2007?


Britain to be hit by SNOW in October... forecasters warn an early winter is on its way

In other news articles I saw mention of La Niña, sun spots, PDO. This is the first article where I saw this: "The UK and Ireland have also been forecast to experience extreme cold conditions and snow from the Arctic for prolonged periods."

With those open, warm waters in the Kara and Barents Sea we should expect some ocean snow effect, right?


Nut brings icebreaker to a halt. No, not a tree-hugger or a pseudo-skeptic. :-)

I've pulled a few strands together and posted a new article:
The first commenter accuses me of cherry-picking. Ah, well! When the trolls attack, you know you are having an effect. LOL.


An article from the BBC about how a decrease in UV radiation might be causing the cold and snowy winters in Europe and North America: Ultraviolet light shone on cold winter conundrum

UV is absorbed in the stratosphere, the upper atmosphere, by ozone. So in the quiet bit of the solar cycle, when there is less UV to absorb, the stratosphere is relatively cooler.

The Hadley Centre model shows that the effects of this percolate down through the atmosphere, changing wind speeds, including the jet stream that circles the globe above Europe, North America and Russia.

The net change is a reduced air flow from west to east, which brings colder air to the UK and northern Europe and re-distributes temperatures across the region.

Dr Scaife emphasises that ultraviolet emissions are not the sole reason why winter temperatures vary.

But understanding the UV link may improve meteorologists' capacity to predict winter weather accurately.

Remko Kampen

Be careful there, Neven. The one recent solar quiet comparable to the recent one is to be found around the year 1905. But the first decennium of the 20th century shows no memorably cold or snowy winters in Europe or North-America.

OTOH the absurdly mild European winter of 2006-2007 happened in de depths of deep solar min and was followed by another very mild winter.

Meantime the trio of somewhat colder than normal European winters 2009-2011 is rather weak compared to 1969-71 to name a lesser known colder trio, and means nothing compared to trio's like 1985-87 or 1940-42, the latter containing two of the biggest winters in the European written weather history (btw also 1939 was fairly cold).

"Dr Scaife emphasises that ultraviolet emissions are not the sole reason why winter temperatures vary." Dare say so!

Chris Biscan

The GFS and Euro both have the DPA going for 10+ days. The euro has been ruthless having it at max intensity for longer.

Both warm the arctic up quite a bit.

Norsex and DMI both show the ice growth stalling right now with both showing flat lines with norsex showing a slight decline from major compaction/flushing.


At the risk of scaring Neven even further, I just had to point out this article that I stumbled across:



Nah, that one didn't scare me, Bill. :-)

Remko, I'm linking to every article that refers to a possible cause for the two recent wild winters on the NH. Suspects are:

1) La Niña
2) Sun (through UV radiation, sun spots or whatever)
4) Open seas due to massive ice pack retreat and warm waters (for instance Barents-Kara, referred to by that paper last year).

As far as I know, what is observed is a combination of the Polar Vortex weakening, allowing cold air to move further southwards. And the snow has to do with moisture in the air (duh). I think 4) could be having to do with the latter, through the ocean snow effect, but I'm not sure at all. I don't have the faintest clue as to what causes the former. Could be a combination of all four suspects.

But maybe if it happens again this year (and some say it will), there will be some more clues.


Look at what a nice Dipole we have (all the isobars nicely leading to Fram Strait):

Remko Kampen

Assessing all information is good Neven :)

There is a suggestion re point 4. It is that perhaps the Polar Vortex is narrowing a bit and centering more over the northern Greenland/Ellesmere region, where the pack has remained most robust and thickest (sea-ice up to a metre thick still percolates some warmth from the sea below).
This configuration could imply more ridging along to a score degrees west of the Greenwich meridian, particularly first half of winter when the rest of the pack is still thin.

As for the others:
1. There is virtually no correlation between EN/SO and winter weather/circulation pattern over almost all of the hemisphere north of the tropic of Cancer, excluding a region around California and the southern USA.

2. There appears to be a slight UV-effect of the sun on the NAO but other drivers like 4 and some apparent unknows blot it almost out of sight. E.g. the present solar situation is comparable to 1900-1910, but the NOA behaves quite differently.
Note: be careful with LIA-analysis centering solely on solar behaviour e.g. Maunder, Dalton Minima. It appears volcanism was the main driver of RWP, MWP and LIA each.

3. PDO/AMO cannot be used to interpret a mere couple of recent winters with, their timescale spanning over half a century. This said given the actual existence of those cycles in the first place!

Russell McKane

Just a point of interest and facination. The voyage of the Healy Research Vessel is clearly tracked on the international Arctic buoy maps.
Obviously they have an active buoy on board and not deployed. It could be useful for lining up the on deck photos with the track path.


Apparently some researchers from the University of Washington have called their supercomputer Kraken Cray XT5

What are those people thinking? How can I trust them if they scare me so much?

Oh BTW, they are using the supercomputer to solve the mysteries of the Antarctic sea ice.

Remko Kampen

Kraken Cray XT5, awesome. Looks like the cause of AGW.

Artful Dodger

lol, in the same way AMSR-E was causing the loss of Arctic sea ice ;^)

Steve Bloom

Link to that methane story, idunno? TIA.

Kevin McKinney

Checking out the Alaska Dispatch article currently at the head of the sidebar--

IPCC 2007 Predictions Too Optimistic--

it contains a link to the actual study abstract, which I hadn't previously read. This passage struck me:

The coupling between the ice state (thickness and concentration) and ice velocity is unexpectedly weak in most models. In particular, sea ice drifts faster during the months when it is thick and packed than when it is thin, contrary to what is observed; also models with larger long-term thinning trends do not show higher drift acceleration.

It seems to say that what we might call the "sea ice drift feedback" has not only been underestimated in most models, but has in fact been of the wrong sign.

And that idea does jibe with one argument I saw--unfortunately I don't have a reference anymore, though I think I might have seen this during the course of a discussion here--that thinning ice should cause less export. (That one didn't--and doesn't--make any sense to me intuitively--but perhaps it was based upon the behavior seen in the models examined in the current study?)


It may be hidden in posts but has there been a discussion as to why Bremen and jaxa seem to have stopped? 3/10 and 5/10. Or is it I'm out in Oman at the moment - but can't see why they would be blocked....

Remko Kampen

Phil - "Sea-ice data update stops for a while due to the suspension of AMSR-E observation."

Instrument malfunction. Cryosphere Today notes "The AMSR-E instrument is currently malfunctioning. If the instrument cannot be revived by Oct. 15, we will switch data sources for our images to the SSMI instrument."

Kevin McKinney, I'm quite surprised. Never heard of this. Counter-intuitive, indeed!!


Thank you Remko


That about thicker ice makes for more drift, is counter-intuitive indeed. One reason could be that thicker is more ridged, because of floes getting shoved on top of each other, and toppling etc. So you have ice protruding high up above the rest of the freeboard, which perhaps could act like a sail?

Daniel Bailey

Neven, I'd made that selfsame point on a discussion thread here some months ago. Others felt differently (and being both busy & not caring sufficiently enough I guess to pursue it) so I let it drop.

I think it makes sense given the consept of even today's thickest ice being structurally weaker (cf the Barber expedition in 2010) than it used to be in "the olde days". In those days of yore, the thickest ice was also structurally the strongest, slabbed into immense floes covering enormous areas.

Today's thinner, weaker ice is both scabrous and fragile, with the slightest of floe collisions shattering the floes into long splinters. Under these conditions it perhaps makes sense that the floes with the greatest freeboard to catch the wind also are those with the highest "escape velocities" to be then ejected/advected out the Fram.

Anybody else? Bueller?

Kevin McKinney

Just to be clear--for I suspect I wasn't--the models showed less drift with thinner ice; the observations in the present study show more. Much more, in fact.

The authors are proposing that difference as an explanation for the well-known underprediction of sea ice decline (by whichever metric) in most models.

So, the latest word is that it is the thinner ice we have increasingly been seeing in recent years which favors increased export through Fram Strait.

By the way, one of the last figures from the study also appears to support Maslowski's esimate of when we might expect to see a sub-1 million SIE minimum.


Hi Steve Bloom,

There is something on the methane expedition story at:


This appears to be an interim report, and it is anticipated that there will be more at the end of this month.


Hi Steve,

That link I've put up doesn't seem to work. It was to a news story published in "The Voice of Russia", written by one Sergei Ivanov and published on 28 September. I hope this should be enough infor for you to track it down.

Daniel Bailey

No, that worked for me, once it was properly formatted as a URL:


Steve Bloom

That article has an almost Soviet flavor. The oil and gas guy is, well, an oil and gas guy, and I imagine the WWF has to be careful to avoid upsetting the authorities.

Just to note that it's by no means good news if the source is micro-organisms (permafrost decay) rather than hydrates. The important thing is the trend, which they'll hopefully have something on this year.

Andrew Xnn

Here is a plot of average methane levels as measured at Barrow Alaska. There is a slight upward trend.


Kevin O'Neill

Increased sea ice velocity is offset by lower concentrations and thinner ice. Net volume exported remains the same.

It should be remembered that though volume export remains constant, the total volume of ice in the Arctic is constantly decreasing; thus the amount exported each year is growing as a percent of the total ice volume.

Bob Wallace

Looks like Inhofe is going to take another run at Monnett and Gleason over the dead polar bear paper.


Bob Wallace

"thus the amount exported each year is growing as a percent of the total ice volume"

Not only would the percent of total ice volume exported through the Fram be increasing, there would be less left in the basin to be melted by the incoming heat and less ice to reflect light back out.

Heat is growing, finding less ice to melt.

Sounds like acceleration to me....


Another ice web cam is in place at Mount Everest:


Hi Steve,

I agree entirely that the tone of the article is very strange.

It seems to me that current Russian petroligarchy would make life very difficult for any Russian scientist who tried to stand between the oil industry and their new happy hunting grounds.

And thanks to Daniel for reposting the link correctly.


Grab a drink, get comfortable, and watch this 1947 Russian (English language) movie about the Great Northern Sea Route:

I stumbled on it while researching historic data on icebreakers for a recent article on the Yermak:

Kevin McKinney

What fun, Logicman!

So it seems the dream of the USSR bureaucrats to achieve "normal shipping" across the NEP by 1950 only came about 60 years behind schedule--long after the demise of the USSR.

Also amusing: the underscore soundtrack which--shall we say?--owes a lot to Wagner's "Flying Dutchman," and the hardware--an engine-room telegraph, I think?--seen prominently at about 5 minutes in, which is prominently stamped "US Coast Guard!" (A Lend-lease program legacy, perhaps?)

Makes you wonder if the filmmakers had their own (faintly subversive) in-jokes going on, in what was probably seen as a pretty unimportant propaganda potboiler.

Kevin O'Neill

The Arctic May Be Ice Free In Ten Years - from the Norway Post

The melting of the Arctic sea ice is progressing much faster and more dramatically than earlier estimated, according to new research by the Norwegian Polar Institute (NPI).

This means that the Arctic Sea could be free of ice in the summer in ten years time, rather than the 50 to 100 years estimated earlier.

NPI mesurements made by moored sonars show a dramatic reduction in the fraction of ridged sea ice, compared to the 1990s. The vast fields of ridged ice thicker than 5 m, constituting 28 percent of the winter Arctic sea ice cover during the 1990s, is nearly gone.

At the end of winter in 2010, ice thicker than 5 m constituted only 6 percent of the total ice mass observed. The combined effect on late winter mean ice thickness is a reduction from 4.3+-0.4 m during the 1990s to a record low value of 2.0 m in late winter 2010.

NPI researchers speculate that increased ocean heat flux plays an important role in the thinning of the thick ice. With the thickest ice nearly gone and the MY level ice thicknesses close to thicknesses typical for first year sea ice, we are approaching a state where favorable conditions could melt most of the Arctic sea ice cover during one summer.

An abstract of a seminar given on the subject by the NPI can be found here: http://www.npolar.no/en/events/2011/10-19-thickness-of-sea-ice-in-the-arctic-ocean.html

Chris Biscan

Ice has current hit the skids...

the dpa is progged to stay in place for the foreseeable future.


Thanks for those links, Patrick and Kevin.


Quote: Kevin O'Neill;
"The Arctic May Be Ice Free In Ten Years - from the Norway Post
The melting of the Arctic sea ice is progressing much faster and more dramatically than earlier estimated,,,"

Kevin thanks for the Link.

Sounds like other institutions are beginning to lend support to Maslowski ( 2016 +/- 3 yrs )

Artful Dodger

I wonder what quality of area/extent data will come from CryoSat2? Perhaps it's already of sufficient quality to replace AMSR-E data...

Artful Dodger

An interesting new Paper was released Sunday, relevant to a topic of frequent conjecture here @ the 'IceBlog:

Bintanja, Graversen & Hazeleger (2011/10/16) "Arctic winter warming amplified by the thermal inversion and consequent low infrared cooling to space", Nature Geoscience (advance online publication)

Pronounced warming in the Arctic region, coined Arctic amplification, is an important feature of observed and modelled climate change. Arctic amplification is generally attributed to the retreat of sea-ice and snow, and the associated surface-albedo feedback, in conjunction with other processes. In addition, the predominant thermal surface inversion in winter has been suggested to pose a negative feedback to Arctic warming by enhancing infrared radiative cooling.

Here we use the coupled climate model EC-Earth in idealized climate change experiments to quantify the individual contributions of the surface and the atmosphere to infrared radiative cooling. We find that the surface inversion in fact intensifies Arctic amplification, because the ability of the Arctic wintertime clear-sky atmosphere to cool to space decreases with inversion strength. Specifically, we find that the cold layers close to the surface in Arctic winter, where most of the warming takes place, hardly contribute to the infrared radiation that goes out to space. Instead, the additional radiation that is generated by the warming of these layers is directed downwards, and thus amplifies the warming.

We conclude that the predominant Arctic wintertime temperature inversion damps infrared cooling of the system, and thus constitutes a positive warming feedback.

The Supplementary Information for this paper is freely available (400 KB), as are two Figures (with descriptions).

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