Sea ice extent update 11: the tables are turning

I'll be regularly writing updates on the current sea ice extent (SIE) as reported by IJIS (a joint effort of the International Arctic Research Center and the Japan Aerospace Exploration Agency) and compare it to the sea ice extents in the period 2006-2009. The JAXA graph is favoured by almost everyone, probably because it looks so nice compared to other graphs (like the one by Arctic ROOS, the University of Bremen and the Danish Meteorological Institute). All the years have a nice colour of their own which makes it easy to eyeball the differences between trends. Most of the betting on minimum SIE is based on the IJIS data. NSIDC has a nice explanation of what sea ice extent is in their FAQ.

July 3rd 2010

2010 had built up a very decent lead over the other years in the past few weeks, but at the moment it has a hard time defending that lead against 2007's incessant barrage of century breaks. Yesterday another lowest melt for the date (July 1st) in the period 2006-2010 was reported (second in a row): a meagre 56,093 square km. Today there has been a slight recovery with a reported melt number of 82,969 square km, but that doesn't really cut it in this phase of the race, does it?

2010 is still leading 2008 and 2009 by a substantial 900K square km, but 2006 and 2007 are about to make the difference less than 400K. On today's date for instance 2007 had a melt of 201,875 square km, the biggest melt ever reported by IJIS. 2010 has to start producing some century breaks if it wants to get to record-breaking territory. This month is the month to do it.

The current difference between 2010 and the other years is as follows:

• 2006: -435K

• 2007: -403K

• 2008: -921K

• 2009: -897K

And here's the IJIS graph:

Whether it's temporary or not, the decreasing melt rate is becoming visible in other graphs as well, such as the Sea Ice Area graph on Cryosphere Today:

If you compare it to the CT sea ice area image I copied less than a week ago for the Arctic Basin Drop blog post you see that the negative anomaly has decreased by more than 0.3 million square km.

But where exactly is the melt stalling? By studying the regional sea ice area graphs on Cryosphere Today I notice that contrary to the past few weeks there's not much action in the Greenland Sea and Laptev Sea:

 

 

But okay, there's not much ice left there anyway so this can't be influencing the overall melt numbers much. In fact the real party poopers are the Canadian Archipelago and the East Siberian Sea, both showing positive anomalies since a few days:

 

 

And what about the biggest and most important region, the Arctic Basin? Like I noted less than a week ago the sea ice area was dropping precipitously, but this drop has also stalled since a couple of days:

 

I'm not sure what is causing this reversal in the trends. Perhaps the temporary reversal of the Beaufort Gyre has brought compaction to a halt and the heavily fractured ice is spreading out and thus covering a larger area. On the Bremen ice concentration maps I notice that all the yellow and orange swathes have disappeared, so perhaps these were caused by extensive melt ponds and these are now accounted for or they have frozen over again (I see on the webcams that the puddling has stalled as well). The temperatures should be pretty toasty in Northern Canada and Siberia at the moment and the AO also looks like it's about to turn positive. I'm not sure what the Arctic Dipole Pattern and meridional winds are doing. I'm going to research that for a blog post in the coming week.

If anyone has an idea what is causing the tables to turn, I'd love to hear it. In the meantime there are more than enough graphs to keep an eye on the coming days.

Comments

[Lord Soth]

I highly suspect that the sudden reversal in cryosphere today results are due to he draining of melt ponds, and the spreading of ice instead of compaction due to wind patterns, and the timing of the breakup of areas of consolidated ice.

The ice is gettng thinner every day, and the timing of the breakup of large areas of consolidated ice, will determine those large drops. At first he breakup of consolidated ice will have a negative impact as it spreads out, but in the end it guarantees the destruction of the once consolidated ice, due to increased surface area subject to melt and the ability for that ice to move into warmer waters.

[Kevin McKinney]

Wow--big upwards revision for the 3rd.

Right now, WRT to predictions, I'm shutting up & watching what happens!

[fredt34]

I can't help remembering this sentence from Prof. Wadhams about Wieslaw Maslowski's models in december 2007 (http://news.bbc.co.uk/2/hi/7139797.stm): "There will be even more opening up, even more absorption and even more melting. In the end, it will just melt away quite suddenly. It might not be as early as 2013 but it will be soon, much earlier than 2040."

BTW, Maslowki is in charge of the PIPS3 model (http://www.oc.nps.edu/~pips3/) - the very one that Goddard uses to desperately try to "prove" arctic ice volume doesn't decline. What an irony!

[Gili1]

Both the Topaz and PIPS2 models claim the only large area with thick ice left is in the East Siberian Sea. This fits well with MODIS images of that area, and is quite different from recent years.

-Gili

[me.yahoo.com/a/Ukc7BaEIw4V8ooR9xfa4huqpMECX7c4DQ_w-]

The Canadian Archipelago seems to be very much a case of the ice breaking up and spreading out over a greater area. The latest MODIS image shows a network of cracks in the ice of the Melville sound and much of the ice elsewhere is highly fragmented.

The condition in the archipelago still appear to be be quite warm (10+ degress C)according to the Uni of Cologne isotherm map, Whereas the condition near the Laptev sea appear to be almost tropical (20+ degrees C).

[andrewt]

More fractures opening up in the Melville Sound ice:
http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r04c02.2010184.terra.1km
Looks like it may breakup in the next few days

[Sepilok]

In the 250 m resolution image the fracture seem to extend thru most of that Sounds sea ice - so I think you are right - as soon as some of these slabs move away - the rest of the cracks will open up.

[Neven]

Another relatively low melt reported.

Andrewt, I have updated the McClure Strait animation. With all the heavy cracking going on in the eastern of the ice bridge I perhaps should have called the animation 'Melville Sound'. ;-)

[Sepilok]

The other area showing lots of breaking up in the latest MODIS image is the area around the new Siberian islands

[Sepilok]

It appears that the 20+ degree temps are having an affect http://www.meteo.uni-koeln.de/meteo.php?show=En_We_We

[Neven]

The other area showing lots of breaking up in the latest MODIS image is the area around the new Siberian islands

Sepilok, I've been wanting to make animations of Siberian regions as well, but it has constantly been so cloudy over there.

[Sepilok]

Hi Neven,
Todays and yesterdays image of the area around the Lyakhovsky island are fairly clear. They show how quickly things can change - yesterday a bit chunk of ice, todays a network of cracks. Some of the bays on the coast have lost about 50% of their ice cover in the last 24 hrs
yesterdays: http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r05c05.2010184.terra.500m
todays: http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r05c05.2010185.terra.500m

[Neven]

You're right, Sepilok. Unfortunately those MODIS images are still not good enough for an animation. I also have to admit that I really don't know my way on the Siberian side of the Arctic! But it was the same for the Canadian Archipelago a few weeks ago and things have gotten clearer after much map gazing.

[Neven]

CT sea ice area has gone down again.

And another huge 27K revision by IJIS.

[Nick Barnes]

Looking at the NWP today on Aqua, I predict that MODIS will show open water all the way from Baffin Bay to the Bering Strait, by this time next week (2010-07-11). There will be lots of big floes, but distinct open water between them.

[Neven]

So fast? Is that possible? That should make for some spectacular images...

How long for the ice floes to be transported out or melted?

[Neven]

Ah yes, I see what you mean. Huge cracks showing.

[Nick Barnes]

I think the floes will take several more weeks to be exported or to melt in place. But more than half of the remaining ice bridge is showing really clear cracks, which I expect to widen and spread in the next few days. So all I'm saying is that wide cracks, at least, will extend along the whole of the channel by next Sunday. The more open water there is, the more swell can build up, which I believe drives a lot of melting and breakup.
I see that Resolute Bay is clearing.

[Neven]

Nick, do you know at what point the direct route of the NWP can be declared 'open'? When it's completely or largely ice-free, or when the ice bridge breaks up all the way through like it possibly will the coming week? If there is no more ice attached from one shore to the other, I would guess the NWP direct route is theoretically 'open', that is navigable.

If I have time tomorrow morning I will make a new NWP animation with the 250m MODIS images. A bit more work, but the extra detail will be enough reward, I believe.

[Steve Bloom]

What's interesting about the western archipelago is that the thick ice which is normally present just to its north isn't there this year. That implies a potential for much greater clearing in that region.

Also of note, comparing PIPS 2.0 2010 versus 2007 maps for today, in addition to the already-noted differences, 2007 appears to have on the order of 50% more 2 meter or thinner ice. It seems reasonable to expect that this thinner ice is much more vulnerable to both heat and wind.

In addition, that big area of 3-5 meter thick ice that's keeping the ESS from melting out as 2007 did should go fairly quickly given how far south it is.

[Steve Bloom]

Re the NWP, I think "open" is generally taken to mean open for safe navigation by non-ice-hardened vessels. Given hazards from mobile ice, I think that amounts to mostly ice-free.

[Artful Dodger]

The Cdn Coast Guard considers waters open when Ice Area falls below 50% in the navigable channel (not fast ice). Recall that in 2007 the NWP was not open until late August.

[Artful Dodger]

Nevin said: "I've been wanting to make animations of Siberian regions as well, but it has constantly been so cloudy over there"

Notice that Noiv's YouTube Arctic Sea Ice Melting animations are cloudless:

http://www.youtube.com/user/noiv

I suspect he's using the MODIS Band 367 image as a mask to remove cloud from the TrueColor images.

You may wish to contact him to learn more about the technique he's using. Awesome work on the blog, Nevin.

[Kevin McKinney]

Hoping all the American readers enjoyed the holiday today!

Sizeable decline today on IJIS--if it survives revisions, which hasn't happened often lately. (Nearly 90k.)

[dorlomin]

John Cook has a new ice article up
http://www.skepticalscience.com/Factors-Contributing-to-Decline-in-Arctic-Ice.html

[Neven]

Thanks for the tip, Artful Dodger! I'm not sure if noiv's trick would work as well for more detailed GIF animations, but I'll be sure to ask him if my newest NWP animation becomes too big and I'm forced to make a video. Perhaps I should start making animations of the entire Arctic as well. This has become even more interesting now with the reversal of the Beaufort Gyre and the slowing melt rate,

Thanks for that link, dorlomin. I'll mention it in the next SIE update, later today.

[Nick Barnes]

I would tend to be quite conservative in using the word "open" for the NWP. I'm expecting it to reach a condition, in the next week or so, in which one of the great 19th century expeditions could have found a way through. But that's hardly "open, which suggests "open for shipping": we're some way away from that. There's a great picture somewhere, released by NSIDC I think: a MODIS view from the west along the deepwater channel in late August or early September: no ice in sight. That's "open".

[Nick Barnes]

The Vilkitsky Strait is also clearing out this week.

[Neven]

Thanks, Nick. Like I said, I don't know much about the geography of the Siberian side of the Arctic. Now I know about Vilkitsky Strait and Bolshevik Island, a name that is more appropriate for an island in the Arctic than in the Caribbean.

Vilkitsky Strait would make for a great animation if it wasn't so cloudy! Perhaps I can find a few good images.