Arctic Sea Ice

Barentsz and Kara

I had grown accustomed to writing Barentsz Sea without the Z, as everyone does. But I've decided to no longer scorn my Dutch roots. The Barentsz Sea has been named after Willem Barentszoon, a Dutch explorer and cartographer who died looking for an open Northeast Passage (now known as the Northern Sea Route) towards the end of the 16th century. At that time family names weren't used universally yet, and many people went through life with just a patronym, just like in Russian classic literature. Hence Willem was known as Barentsz., short for 'Barents zoon', the son of Barent.

The Barentsz Sea and its neighbour the Kara Sea are giving us an exciting prelude this year, as we await the melting season to start in about a month and a half from now. Large swathes of sea water that ought to be frozen by now, are still open or have opened up in the past fortnight.

According to the Norwegian Meteorological Institute this is what an average January (1976-2006) looked like in the region:

And this is how it looks now, one week into February:

SIE 2011 update 21: post mortem

During the melting season I'm 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 2005-2010. NSIDC has a good explanation of what sea ice extent is in their FAQ. I also look at other things like sea ice area, concentration, volume, temperature and weather forecasts, anything that can be of particular interest. Check out the Arctic sea ice graphs webpage for daily updated graphs, maps and live webcam images.

September 24th 2011

This is the last SIE update for this melting season, which ended about two weeks ago (feels like an eternity). I have basically said everything I think needed saying with regards to the minimum, so I won't repeat myself here. Just like last year I've had a very educative experience, and I'd like to thank the 'old' crew and newcomers for all the info and inspiring speculation they've been bringing to this little corner of the Internet. That's what's making this blog worthwhile in my opinion.

As always I'll start with the IJIS sea ice extent graph:

We can see the upswing when the melting season ended abruptly on September 9th. After a few days the increase slowed down and it's now more or less tracking 2008. The interesting thing to do is to try and find out what the mechanism is behind the uptick and the subsequent slowdown in increase.

It has obviously everything to do with the weather at this stage of the transition phase between melting/compacting and spreading/freezing, so I suggest we first have a look at this animation of images from the DMI Centre for Ocean and Ice that I've saved:

Final score: 2011 vs 2007

Now that I've called the minimum, it's time to have a look at the differences between the two years with the lowest minimums in all data sets. This post will be a potpourri of different factors.

If we look at the six most important data sets - which IMHO are IJIS extent, NSIDC extent, Cryosphere Today area, Uni Bremen extent, DMI extent and PIOMAS volume - we see that this year a new record has been reached in three of them:

In the remaining three (NSIDC, IJIS and DMI extent) 2007 still holds the record low, but 2011 brushes past very closely and is firmly in second place:

If we compare the sea ice concentration maps from the University of Bremen we can see how close 2007 and 2011 match, despite differences in final shape:

Some more flash melting?

Update September 6th 2011: Some of the ice that was gone in the preliminary map for September 5th returned in the final version. Below to the right there's a new animation that shows maps for the 4th, the preliminary and the 5th.

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Today's preliminary sea ice concentration map from the University of Bremen holds yet another surprise. A large area of low concentration ice has suddenly disappeared in what I refer to as the Laptev Bite, the place where warm waters from the Laptev Sea have been munching their way into the ice pack.

Of course, just as last time, this doesn't mean the ice has totally disappeared. It just doesn't show up on the image because the concentration has gone below the threshold, for whatever reason. And mind you, this is a preliminary map. The definite version might still show a different picture.

Nevertheless, that's quite a bite!

I'm not sure what the reason could be. This time there was only a smallish cyclone passing by, not like that big one from the last flash melting event.

But maybe that was enough to stir the thin ice up.

Let's wait and see what happens next.

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Update:

Here's an ENVISAT radar image of this area for September 5th from Arctic.io:

2011 End Zone

Last year I wrote a series of five posts called End Zone, comparing different aspects of the final phase of the Arctic melting season in different years, to be able to predict a bit what those last weeks of the 2010 melting season could be holding in store. A lot of that ground work still stands, so I don't have to repeat it this year. In this post I'll be looking at sea ice concentration and sea surface temperatures mainly, as these are most interesting right now. I basically said everything there is to say about atmospheric pressure, air temperature and ice displacement (no more PIPS, sniff) last year.

Sea ice concentration

I'm trying out something new here, which I hope you'll like. I'm comparing the years of the new Arctic era with 2011 on August 29th by fading the images:

2011 looks quite a bit like 2007, except that the large protuberance is sticking out in the East Siberian Sea instead of the Laptev Sea. That protuberance blocked the Northern Sea Route right till the end of the 2007 melting season. This year it's been wide open since very early on.

Flash melting

I introduced the term 'flash melting' in a recent SIE update. It was a pun on the term 'flash flooding' where lots of rain falls out of the sky in a short amount of time, causing creeks and rivers to flood very fast. I based the concept on the state of large parts of the ice pack in the Beaufort, Chukchi and East Siberian Seas that looks like slush puppie on the satellite images. It seems so weak that one can't help but wonder if it will all "just melt away quite suddenly", to quote Professor Peter Wadhams from this 2007 BBC interview (as I did in the piece CAPIE hits record low).

In the last two days something weird has happened on the sea ice concentration maps of the University of Bremen, with large swathes of ice suddenly disappearing from the radar (the full animation from August 6th-22nd can be watched here) on the upper left of the image:

Update August 24th: Added yesterday's image. Could be the sensor is picking up ice again.

Update August 25th: Added yesterday's image. No more flash melting (thank God).

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This looks so spectacular that it could just be a fluke, a deceived satellite sensor. Flash melting is a nice term for fast melting, but it can never be as fast as flash flooding. It ought to occur more on a time scale of say one week (which is very fast in the Arctic). Because however weak the slush puppie ice may be, it still takes large amounts of energy to make it disappear completely.

On the other hand IJIS extent took a bit of a nosedive with a reported melt of 98K square km for yesterday's date, and there's a huge cyclone battering the ice as we speak:

2011 Slush Puppie Animation

If last year was characterized by holes in the middle of the ice pack, this year is the year of rotten ice. A term I like even better is Slush Puppie, because it's ice that's not only very fragile, but keeps getting churned around as well. This ice is becoming a more and more dominant factor when it comes to setting records. Can it spread out and hold out long enough until the sun goes down and freezing temperatures end the melting season (like it did last year)? Or will it suddenly just fall apart and disappear?

On the LANCE-MODIS satellite images we can see that large areas at the edge of the ice pack are covered with this weak ice, especially in the East Siberian, Chukchi and Beaufort Seas. But as clouds don't allow me to make a decent animation, I've returned yet again to the University of Bremen's excellent archive of sea ice concentration maps.

Do not be distracted too much by the rapidly changing colours, and instead concentrate on the edges of the ice pack or focus on one point. Also check out how the warm water from the Laptev Sea is eating its way into the pack:

I will try and update this animation on a daily basis. Don't forget: you have easy access to this and all other animations by clicking on Animations in the upper menu bar.

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Update September 8th: Added images from the previous 2 days. Some of the ice in the Laptev Bite has re-appeared, as it is being pushed together again.

Update September 6th: Added images from the previous 3 days (and removed a couple). There was some more flash melting in the Laptev Bite.

Update September 2nd: Added images from the previous 3 days. The ice is still slowly disappearing.

Update August 31st: Added yesterday's image. More ice vanishing.

Update August 30th: Added images from the previous two days. Some of that ice on the Pacific side is disappearing again.

Update August 28th: Deleted a couple of images (up to the 20th) and added a couple of images. Some of the 'melted' ice seems to be flashing back to life.

Update August 23rd: Added yesterday's image. More flash melting in the Beaufort sea. Could be a fluke. See this post.

Update August 22nd: Added yesterday's image. Lot of flash melting in the Beaufort sea, apparently.

Update August 21st: Added yesterday's image.

2011 Fram Strait Animation

22nd of July: I'm a bit too early with this, but that's to make up for the things I'm late with. Due to the recent switch in weather patterns it is safe to expect that - at least for a while - we'll see increased advection of ice through Fram Strait. As last year's Race to Fram Strait blog post(s) quite nicely showed the ice transport starting halfway August, I'm starting this animation now.

The images were retrieved from the Uni Bremen sea ice concentration map archive, which I prefer over cloudy MODIS images. This animation will be regularly updated and can also be viewed through the animations page (button in the menu bar).

Now, without further ado:

Update September 8th: Added images from the previous two days. Here too some of the ice reappears, but obviously the winds are tearing into the ice pack.

Update September 6th: Added images from the previous two days. The ice pack seems to expand a bit more towards the Atlantic. Update 2: And some of the ice goes missing on the preliminary map.

Update September 3rd: Added images from the previous five days. Not much happening, I think. Rather than seeing transport, we see the edge of the ice pack receding.

Update August 30th: Added images from the previous three days.

Update August 26th: Added images from the previous two days. The ice is one the move, although the ice pack isn't really expanding towards Fram (due to melting in warm waters?).

Update August 24th: Added images from the previous four days. Transport could be in the works in a day or two.

Update August 21st: Added images from the previous seven days. Still a stalemate.

Update August 14th: Added images from the previous four days. The ice pack is pulling back again.

Update August 11th: Added images from the previous two days, and removed images from July. Transport is steaming full speed ahead.

Update August 8th: Added images from the previous three days. Some serious ice transport going on there. If this keeps up...

Update August 5th: Added images from the previous three days, and removed images of the first ten. As was mentioned by Paul Klemencic transport towards the Atlantic has resumed.

Update August 2nd: Added images from the previous three days. Ice transport might be resuming.

Update Juy 31st: Added images from the previous two days. Due to atmospheric pressures ice transport has been transported towards the Laptev Sea. One of the clear signs is the area of water opening up on the northeast coast of Greenland from July 26th onwards.

Update July 28th: Added today's image. Still no ice transport through Fram, and bound to stay that way for a few days to come.

Update July 27th: Added today's image. Things moving more towards Olga Strait (between Svalbard and Franz Josef Land).

Update July 26th: Added today's image. Things moving more slowly now.

Update July 25th: Added today's image.

Update July 24th: Added today's image. If you look carefully, you see the ice pack has started moving towards the Svalbard archipelago (again) since July 22nd.

Update July 23rd: Added yesterday's and today's image.

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The transport isn't very apparent yet, only if you focus on the area between Svalbard and Franz Josef Land (bonus question: what was the name of that Strait again?). Coincidentally I came across this interesting paper by Ron Kwok (2009) called Outflow of Arctic Ocean Sea Ice into the Greenland and Barents Seas: 1979–2007.

On a final note, I want to add that there seems to be quite a bit more sea ice in the Greenland Sea than usual:

Hudson bye-bye

Apologies for the corny title.

As promised in the previous post on Hudson Bay I have had another look at how this year's melt compares to other years. 2011 is still around 200K behind last year:
Here's how it looks based on sea ice concentration maps from the University of Bremen archive:

Hudson Bay

After having kept a close watch on the Bering Sea (which is now practically empty of sea ice), we turn our attention to the Hudson Bay, by comparing this year's sea ice concentration with that of previous years.For this I have again gratefully made use of the University of Bremen archive of sea ice concentration maps:

If we disregard the colours and just focus on the shape of the ice pack in Hudson Bay, we see that 2006 and 2010 had less area covered than this year. It looks quite similar to 2005 and 2007, although the ice pack in those years seems to be less concentrated than now.

When the melting abruptly stalled last year towards the end of June there was some speculation that this had to do with the rapid melt of the 'easy ice' in Hudson Bay coming to an end. This might have played a role at first, but the slow decrease of sea ice area and extent continued all the way to mid-August due to weather patterns.

This year the rapid melting seems to have taken place elsewhere (Siberia) as 2011 is approximately 200K square km behind 2010 in Hudson Bay, according to Cryosphere Today: