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Artful Dodger

Yes, Peter is quite right. Here are IJIS summaries, sorted by Avg SIE:

Year:	May Avg:	May Decr:
2,006 11,659,975 -1,346,406
2,004 11,744,138 -1,141,250
2,011 11,876,396 -1,581,250
2,007 11,941,527 -1,301,719
2,010 11,995,882 -2,097,500
2,005 12,049,909 -1,388,125
2,008 12,123,690 -1,400,313
2,003 12,182,359 -1,220,157
2,009 12,327,515 -1,672,500

Artful Dodger

Christopher: Temperature is not Heat.

L. Hamilton

Peter, you're right, not sure what I was looking at in the IJIS data, 2004 and 2006 means are both higher. Not so with UB, CT, or (as best I can see) DMI since 2005.

Christoffer Ladstein

Right, Lodger, perhaps that error is to be blamed upon a stay in a Hot sauna too close to the Heater, after a stay in the municipal swimmingpool together with 2 of my kids. The Oslofjord doesn't tempt any such desires yet, ought to move to Arkhangelsk where they're experiencing close to 30 degrees C these days, must bring the Bay of Kola to the "boiling" point. I expect the seatemps around Novaja Zemlja to rise to around 5 C in a day or 2...
Most of Norway had temps slightly above normal in May, the most positive anomaly came "as usual" at Svalbard, +2,5 above normal (+ 4,1 last May...). I might just in the same breath of air mention that the trend up there is much warmer than normal winters, but not so extreme summers. But....2007 compared to the chilly summer of 2010 show that Jun-Aug. was 4,4 C warmer in 2007. This fact have been pointed out earlier, I know, but last years extent fell sharply but landed too early, all due to a not too good summer!?

No matter, summer returned here today, so cheers and happy holiday tomorrow!

Daniel Bailey

Neven, you have a tröllstalker.

Kevin McKinney

"Mac's update late?"

Maybe, Christoffer--or maybe the computers talk slower in Georgia, too.

Lord Soth

We are now in first place for IJIS with a near century loss last night. Currently at 11030625 for June 1.

Currently 21K below 2010, so I give it a 50/50 chance of surviving the update in a few hours.

Gas Glo

Yes, but what is happening with CT area? 3 consecutive rises so now 129k above 3 days ago.

Christoffer Ladstein

What a laugh! The update brought it 625 km2 ABOVE 2010, that's fairly much the same as a small farm in the midwest, or half of New York City area!!! Tomorrow then will bring it below the 11 million mark, 1 day earlier than 2010..... Then we set a new goal, 10 million! June 14'th perhaps?!


I noticed that upswing, too, Gas Glo.

But whatever it is, the most recent prediction from Topaz (published Jun 1)doesn't include it.

I've posted the Topaz data by CT region for both Topaz3 and Topaz4, in case anyone's interested (remember the last 10 days are subject to revision):


(Remember that the Bering Sea is not included. That's why we crossed 11M on 5/30.)


Hi Bfraser,

Really good to see you back here.

Any chance of an update on your TOPAZ by CT area post? I really appreiated the original, and would be very interested in any update...

Lord Soth

I suspect the Cryosphere today is having calibration issue. The biggest change is in the high arctic. Could be a melt pond issue, but probably to early for that.

Whatever it is; its an artifact and is not real.

As far as IJIS, I would call call 2010 and 2011 a statistical tie. Like how may pixels can 625 Km be. If they are using 25 sq km grids, it would be 1 pixel.


@idonno, actually, I have updated some of the graphs from last time with the new information, but I haven't figured out how to post them. Can anyone recommend a site (like snipt, but for pictures)? Or does anyone want to perform some new analysis based on the raw data that I just posted?

@Lord Soth. 625 km2 is 4 pixels. I agree that it is a statistical tie.

Wayne Kernochan

My apologies for being a bit off-topic for this post, but PIOMAS seems to have quieted. Included in http://thinkprogress.org/romm/2011/06/02/234291/royal-society-7f-4c-world/ is a just-published Met-Office projection. It is for the 2090s but also for a more conservative scenario that we are presently on. Joe Romm appears to believe that for our present scenario (A1F1), this graphic applies to the 2060s, not the 2090s. My interpretation is that by the 2060s, temps in the Arctic will have warmed by 17 degrees C.

Gas Glo

Can anyone recommend a site (like snipt, but for pictures)?

I use flikr


Can anyone recommend a site (like snipt, but for pictures)?
Posted by: Bfraser | June 02, 2011 at 17:45

You can use http://imageshack.us/ to post images and graphs that you can link to here, like this:

Or you can make them small enough, and put them directly into your comments:

Artful Dodger

LS: IJIS uses 6.25 km square 'cells' to compute extent. Therefore SIE changes in discrete quanta of 39.0625 km^2 (SIE is always rounded to the nearest whole number).

This was discussed last year. Search this blog for "least common divisor".


michael sweet

On the North Pole web cam picture number two it appears that the ice flow the camera is on has cracked in half only a short distance away from the camera. Some of the instruments are on the other side of the crack. Presumably they used the thickest ice they could find. What does this mean about the stability of the ice at the pole???

Peter Ellis

Is that a crack, or is it a pressure ridge forming? Not sure we can tell until we get a clearer picture.

Kevin McKinney

If I had to guess right now, I'd say pressure ridge.

Daniel Bailey

Agreed, Kevin. Pressure ridge. The left half of the field shows clear uplift along the line. The right half is less distinct.

There's evidence of larger pressure ridges and stacks/slabbing in the background as well. Granularity gets bad when zoomed in too far.

If one were to venture a guess, I'd say the foreground ridge is about 1 meter, +/- 0.5 meters in places.

I know budgets are tight, but the new HD cameras aren't all THAT expensive...


I don't ordinarily like to disagree with Lodger, but I'm pretty sure that the pixel size is 12.5km (or at least it was at the start of 2011).

Also, here are two updated graphs (one for thickness and one for extent/area/volume).


Artful Dodger

I too am glad you're back, Bill :^)

On August 30, 2010 at 18:30, Phil wrote:

"the data is compiled from the signal using 6.5x6.5 areas ('pixels'), so the greatest common divisor is 156.25 sq km..."

So not quite right yet, as 12.5 x 12.5 is 156.25 km^2



@Michael, Petre, Kevin and Daniel
I think it is a crack :
and I think that the block across the crack as moved left to right

michael sweet

Nice series of pictures. It looks to me like the other side has moved also. The middle picture looks like the far side is undercut, perhaps the two sides rubbed together for a while.

Daniel Bailey

@ Paolo

Nice. I agree with Michael the second of your 3 pix is the most significant, showing what appears to be open water in a lead.

Now that the floe is fractured, it will open and close repeatedly. Each time the rupture edge will either be forced above or below the colliding edge from the far side of the rift.

Eventually the slabbing could endanger the webcams themselves (they must be close to have enough elevation to see open water in the lead).

Ice looks wafer-thin. Quite unlike that of 50-60 years ago...

Patrice Pustavrh

Well, it is both pressure ridge and crack, nice description here:


It change very fast
24 hours between the first image and this one


1) The opening and closing are very fast
2) The other side has moved
3) The opening is not caused by “extreme cold” and not any “freeze again” and “temperatures rises”
No, I don’t see any link between what we see and the description from Wikipedia
(Sorry for my English)


We can see “pressure ridge” with the other webcam:

michael sweet

The cameras cannot survive the melt season when the ice edge is so close at the start of June. Should we guess when they will stop transmitting? Does anyone know how fast the edge of a flow erodes during the melt season? It looks to me like less than 100 meters to the edge now from both cameras.

Peter Ellis

Seems tailor-made for an animation of the images from camera 2 - maybe when our gracious host gets back?

Kevin McKinney

Yes, Peter, that would be a good animation project!

On the pressure ridge/lead question, I don't much care for this particular Wikipedia article (much though I love Wikipedia as a convenient source in general): I'm not a expert, but clearly there are multiple possible causes for pressure ridges to form--not just thermal stress. (In fact, I bet it's not even 'normally' thermal stress.)

But it's equally clear that the ridge *does* also imply cracking, and that divergence can turn a 'ridge' into a lead very, very rapidly. Seems like this sequence of images illustrates that nicely.


I see two crack, the first very near right after a stick (the little dark mark in the centre of the picture), and the other more far.
The ice continues to move (and I think always left to right).
Michael, I think too that this camera not survives the melt season.
I not find analogous in the previous years and the animation project is a very good idea!!


Sorry the second link is bad (06/01!)


Research aircraft Polar 5 returned from spring measurements in the high Arctic
Published: Monday, May 16, 2011

One of the key aspects of the expedition were large-scale sea ice thickness measurements in the inner Arctic, in which researchers of the Alfred Wegener Institute and the University of Alberta cooperated closely. For this purpose they used a four metre long electromagnetic ice thickness sensor, called EM Bird. The Polar 5 towed the sensor on an 80 metre long rope at a height of 15 metres above the ice surface for the surveys. A preliminary evaluation of the measurement results shows that one-year-old sea ice in the Beaufort Sea (north of Canada/Alaska) is about 20-30 centimetres thinner this year than in the two previous years. In 2009 the ice thickness was 1.7 metres on average, in 2010 1.6 metres and in 2011 around 1.4 metres.

The research aircraft Polar 5 of the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association returned to Bremerhaven from a six-week expedition in the high Arctic on May 6. Joint flights with aircraft of the European and American space agencies (ESA and NASA) were a novelty in sea ice research: Simultaneous measurements with a large number of sensors on three planes underneath the CryoSat-2 satellite led to unique data records.

Lord Soth

2011 IJIS is now back in third place, but not by much, two days after is made first place for ice lost.

From June 5, 2010 it took a steep dive with many century drops. Much of this was driven by the rapid ice loss in Hudson Bay.

Envirnonment Canada is predicting that the breakup and clearing events in Hudson Bay is going to be near normal, despite the fact that Hudson Bay froze over much latter, its been warmer this winter, and the ice is much thiner than last year.

When it comes to the Canadian Ice Service, they are a ultra conservative bunch, when it comes to predictions, but I guess they don't want ships plying ice infested waters, so I see where they are coming from.

I think they are wrong, and the 2011 will start taking a nose dive, driven by Hudson Bay ice lost, like in 2010, but it could be delayed by a few days to a week, due to weather related events.



124 000 drop. Pre revision.

Lord Soth

Update in revision.

Its official, first century lost of the season of 104,219 sq km

Christoffer Ladstein

Finally!!! I must say I agree much with your point of wiew upon Hudson Bay, and also the weatherprognosis along the Sibirian and Greenland coast, "just have to" lead henceforth to a lot of century-losses in the next 2 weeks. I am more curious about what Nevens headline for what's taking place at the very North Pole point.... The North Pole Divided, The North Pole "continental shelves" slip apart.....The Russian Submarine Tourist-season started early this year....
We better wait and see, exciting anyway!

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