Arctic Sea Ice

Crack is bad for you (and sea ice)

The previous pun - cracks of dawn - was wearing off, and the comment section was getting full, so here's a new pun and blog post dedicated to the cracking event that started in the Chukchi and Beaufort Seas a couple of weeks ago, and then moved on to the multi-year ice against the Canadian Archipelago. This is also discussed in the Arctic Sea Ice Forum (ignore the security warning and make an exception as https is actually safer than http).

This image was posted yesterday by Chris Reynolds from the Dosbat blog:

To recapitulate: It is normal for the ice to crack and for leads to occur. However, this is very extensive cracking and there are some very big leads, and all of it seems to come earlier than expected. Given last year's melting mayhem and the low amount of multi-year ice, it makes one wonder whether this early cracking will have any effect in the melting season to come.

There are still several weeks to go before this part of the Arctic is going to start melting, up till then the ice will actually thicken some more, even when the Sun's rays start to reach the ice. But the ice is already getting broken up in smaller pieces, which means that 1) the pack becomes more mobile (like we saw last year), and 2) the thin ice that now grows to fill up the leads, will go first when the melting starts, potentially leading to more open water between floes to absorb solar energy and convert it to heat.

But maybe not. Maybe this will have zero influence. We don't know. That's why we watch.

PS A-Team did some more of his magic and produced this image showing the temperature of the ice and the cracks between floes (click for a larger version):

The cracks of dawn

I was hesitating whether I should write about this (besides my personal combination of busy/lazy) for a couple of days, because the Arctic is such an amazing place that it's easy to get carried away. When you see something for the first time, it's tempting to go: "Oh my Gawd, that haz got to be the first time!" That happens to me a lot, especially during winter. It's only logical as we are seeing a lot of things for the first time, or for the first time since a very long time. But there still remains a very fine line between 'unique' and 'unusual, but not unique'. A line that can sometimes be difficult to tread.

For instance last year at the start of February I wrote about the spectacular lack of ice in the Kara and Barentsz Seas, notably around Novaya Zemlya. I had a hunch that this was pretty much unprecedented during the satellite era and said as much in a guest post for Climate Progress. I was mildly criticized for it by the NSIDC's Walt Meier via Climate Central (and I will never forgive him for it ;-) ). Now the hunch turned out to be reasonably correct - although there had been a similar retreat of ice at a later date in 2011, caused by wind patterns - but I didn't invest the time to make sure it was.

This year things are calm in the Kara and Barentsz Seas. At the surface that is, with not even a breeze towards the coast to show how strong or weak the ice is. But as usual, when it's calm on one side of the Arctic, something is going on on the other side. Some commenters have been keeping a sharp eye on this, and I think it now merits a blog post of its own, if only because of the possible implications this event might have for the ice pack once the melting season gets underway. And it's big time spectacular.

Last week, on February 22nd commenter A-Team - who has really been animating the blog lately, figuratively and literally speaking - made the animation you see on top of the post, showing massive cracking in the Beaufort Sea. In the following days fellow commenter Jim Hunt picked up on that and wrote a blog post on his Econnexus blog called Arctic Sea Ice is Cracking Under the Strain with a spectacular image of the ice pack in the Beaufort Sea on February 27th.

Meanwhile over on the Arctic Sea Ice Forum commenter BornFromTheVoid remarked that a similar thing occured last year in April. A-Team was quick to turn that event into an animation (that I had to edit a bit to cut down on size):

Open Thread February 2013

The previous open thread has gotten full enough, so here's a new one.
We might want to kick off with this animation made by commenter A-Team:

His comment:

Don't miss this -- it's happening right now, by the hour -- so head on over to 80N 150W. A huge fracture has been opening a bit east of Barrow, Alaska the last few days and it's really accelerating. The AVHRR images come up every few hours as the satellite comes over -- but they're not archived so you have to "be there" to catch them. I attached a still of the key region with a few land features labelled and an approximate distance scale as the animations is intended primarily to illustrate pack ice motion.

The imagery motions agree quite well with the Navy HYCOM ice speed and drift animation. That predicts five days out and so gives some indication of what to expect. I just attached a still for today. All the ice is moving the same way, clockwise in the Beaufort Gyre. It is just that the ice southeast of the lead just can't keep up. The ice no longer has the mechanical strength that it once did and so is fracturing under extensional tension.

Thanks for keeping an eye on this, A-Team!

Stronghold

I think we all remember what the conclusion was after the last freezing season (see 2011/2012 Winter analysis):
sea ice on the Atlantic/Siberian side of the Arctic looks vulnerable, sea ice on the Pacific/North American side should be thicker. So far there has been a very clear confirmation of the first half of this conclusion, in that the ice on the Atlantic side of the Arctic, along the Siberian coast, has retreated very fast, perhaps even faster than last year.
This comparison I made a couple of days back (for the Fringe Fries 2 blog post) shows it well. For a more recent comparison I refer you to the Concentration Maps page on the ASI Graphs website.

I now want to take a look at how the ice on the other side has been doing so far. The Pacific/North American side basically consists of three regions: the Canadian Archipelago, the Beaufort Sea and the Chukchi Sea. In last month's blog post concerning the Northwest Passage it became clear that the Canadian Archipelago was mostly filled with first-year ice, but because of a relatively cold freezing season the ice was probably a bit thicker. The ice in the Northwest Passage and the rest of the Archipelago has been holding up pretty well, better than in previous years (as confirmed by the MASIE extent graph), but due to high temperatures and quite a bit of insolation in the last couple of weeks, the NWP now seems to be breaking up from the inside out. As the fast ice in Nares Strait broke up 10 days ago and ice transport from the Arctic Basin is about to start, I don't think the ice in the NWP is going to hold out much longer.

Because the Chukchi and Beaufort Seas are neighbours, I have made this comparison of University of Bremen sea ice concentration maps on July 7th in the 2004-2012 period, showing both regions (click for a larger version):