Arctic Sea Ice

2012/2013 Winter Analysis

The melting season is about to shift one gear higher, and so I thought it'd be useful to have a comprehensive look at this past winter (just like we did last year). As we saw in this recent PIOMAS update, it seems that this year's conditions for ice formation were better over on the Siberian side of the Arctic.

The Beaufort Sea had relatively little multi-year ice flowing in which should make the pack weaker there, as evidenced by the large cracking event of February and March. The image on the top right shows a map of the ice pack, where this year's thickness is compared to last year's (red = thicker, blue = thinner).

I want to look further into this by comparing the 2012/2013 winter with those of previous record years, such as 2006/2007, 2010/2011 and 2011/2012. Click on the images if you want a larger version.

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):

NSIDC Arctic sea ice news September 2012

A couple of days ago the NSIDC released its latest analysis for the month of September.

For the exact numbers with regards to the shattered record I refer you to the article itself. This graph says it all:

The analysis then moves on to some interesting comparisons with 2007. First off, the differences in atmospheric patterns, something I wrote about at the end of July (Arctic atmosphere June-July 2012):

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):

Northwest Passage still chock-full of ice

The season of contrasts continues. The conclusion after the freezing season that the ice on the Atlantic/Siberian side of the Arctic looked vulnerable and the ice on the Pacific/Canadian-Alaskan side of the Arctic should be thicker than usual, is extending itself into the melting season: Whereas the Northern Sea Route could be opening up in record time, the fast ice in the Northwest Passage has still to start breaking up.

We now have four seasons of wonderful satellite images provided to us by the LANCE-MODIS data system, and so we have an animation that allows us to compare this year's situation with that of previous years:

Even though yesterday's image (day 164) is 4-5 days behind the other years, it's as clear as day that this year the NWP is very slow to open up. One partial explanation for the discrepancy with other years so far is air temperature. Take for instance the temperature anomalies for the first three months of the year (source: NOAA daily mean composite page):

2011/2012 Winter Analysis

I'm starting this blog post off with a conclusion that was reached a while back already: sea ice on the Atlantic side of the Arctic looks vulnerable, sea ice on the Pacific side should be thicker.

Right, with that out of the way we can now look at various aspects of the 2011/2012 freezing season, and compare them to previous years, to be precise the previous freezing season of 2010/2011, and the freezing seasons leading up to and following that other record year: 2006/2007 and 2007/2008. Simply put: I'll be comparing 2007, 2008, 2011 and 2012 before their respective start of the melting season.

I'll try not to use too many words, but I'll be using a lot of images. Click on them images if you want a bigger version.

Ice age

I'll start with the AARI ice age maps. These images are for the end of April, and they look upside down, because it's from the perspective of the Russians who produced them:

Another source of info on MYI

Just when you thought you knew it all, someone shows up with something new. That someone is Bob Wallace commenting in the latest post on CT SIA long-term regional graphs. And that something is this website showing the age of Arctic sea ice: Arctic Ice Age.

This website has animations for each month of the past 28 years, based on data provided by James Maslanik and Chuck Fowler, which are also used for the NSIDC March and September analyses of ice age distribution. It's a great tool to compare ice age distributions from year to year, and it even has an animation showing the weekly development of the 'ice year' since the start of the freezing season up to present. The only minor quibble is that this animation is still showing the freezing season starting in 2010.

But I'm definitely not complaining. Just like the CT SIA long-term regional graphs, this is the kind of info that makes it visually crystal clear to even the layest of lay persons what is going on in the Arctic. Thank you for putting this out there.

NSIDC Arctic sea ice news April 2012

Interesting bits from the NSIDC monthly analysis:

Arctic sea ice enters the spring melt season

Arctic sea ice reached its annual maximum extent on March 18, after reaching an initial peak early in the month and declining briefly. Ice extent for the month as a whole was higher than in recent years, but still below average.

As the melt season begins, researchers look at a variety of factors that may contribute to summer ice melt. While the maximum extent occurred slightly later than average, the new ice growth is very thin and likely to melt quickly. Ice age data indicate that despite the higher extent compared to recent years, the winter sea ice continues to be dominated by younger and thinner sea ice.

A first clue

However unpredictable it is, we still like to gather as much information as we can about the coming melting season. Obviously it's important to get an idea of what happened to the Arctic sea ice during the last freezing season. We've just witnessed the spectacular retreat of ice and late freezing in the Barentsz and Kara Seas and know that the Arctic Oscillation was mostly positive this winter, which ought to have caused increased export of sea ice through Fram Strait.

This has now been confirmed through a new NASA study by Josefino Comiso (published in the Journal of Climate):

still image captured by Arcticicelost80 from the video in the NASA news release

The NASA study shows much more, of course, about the long-term decline in MYI, but to be honest I'm primarily interested in what it can tell us about the coming melting season, as everyone here knows about long-term declines. The graph above shows the amount of multi-year ice (MYI) on January 31st since 1980. This year's MYI cover on that date is just a tad higher than that of 2008, which was extremely low due to the preceding record melting season of 2007. I'm expecting James Maslanik's yearly ice age percentage graph to come out soon (probably the next NSIDC monthly summary) and Arctic.io has promised to make a video of ASCAT radar images of the Arctic sea ice pack during winter (like he did last year). That will give us a more detailed look with regards to MYI.