Arctic Sea Ice

Our beloved ice pack

People who have kids probably know that feeling when their kid has a fever and they watch him/her for a while at night to see how he/she's doing. That's what I felt when dabize sent me his latest declouding art, a composite image from the LANCE-MODIS satellite images (click for a larger version):

Dabize explains:

This is essentially a photomontage of Days 228-232 for tiles r03c03,r04c04,r03c04,r04c03 (terra, 1km)

I blurred the cloud tops of any area that had simply NO clear weather over the past 5 days.

This had the effect of making some areas of cloud look a bit like ice, but I think the difference is clear in most cases.

Our kid, 2012, looks sick at the edges, but well enough in the centre to carry it through the rest of the melting season and spare some shamelessly goalpost shifting people the embarrasment of having to eat defrosted crow. I don't know about the rest of the family yet. 2012 wil probably infect its sibling years. We'll see as soon as 2013 develops its first fever.

Arctic storm part 3: detachment

Yes, ladies and gentlemen, the Arctic summer storm is still there. After approximately 48 hours (which is long for an Arctic summer storm) it has weakened some compared to yesterday or the day before, but as far as I can see sea level pressure in the centre of the storm is still around 970 mb, which is low.

And so we're still seeing significant changes on the Uni Bremen sea ice concentration maps. Here's the animation from August 3rd to 7th:

That large patch of sea ice in the East Siberian Sea is almost entirely detached from the main ice pack. This is something I for one have never seen before, and I wouldn't be surprised if it's unprecedented in the satellite era. We have speculated a lot about this in previous melting seasons, but now the moment seems to have finally arrived. The fact that the ice pack can get divided like this, is yet another sign that the ice is exceptionally thin, as thin ice gets pushed around more easily and melts quicker, leaving open space between thicker, slower moving ice floes.

I've also updated the animation of DMI sea level pressure maps that shows the development and position of the storm:

Arctic storm part 2: the color purple

A new day with new information. Here's an animation of Uni Bremen sea ice concentration maps from August 3rd-6th:

We see some more flash melting from the 5th to the 6th on the edge of the ice pack in the Beaufort Sea region, although technically I think this is more compaction than real melting. We also see some of the early flash melting flashing back, or 'unflashing', in the East Siberian Sea. It looks like that large swath of ice there has almost detached itself from the main ice pack.

On this animation of DMI sea level pressure maps we can see how the cyclone developed from the 3rd to the 6th. The purple in the centre of the storm shows how low sea level pressure was and still is (lowest I've seen in yesterday's reports was 963 mb):

Arctic storm part 1: in progress

This is what I meant when I said 'flash melting' yesterday:

Now it's there on the Uni Bremen sea ice concentration map, the next day, poof, it's gone. Mind you, not all of it is gone, the sensor is thrown off a bit due to that crazy cyclone downstairs, but it ain't exactly good for the ice if you catch my drift.

Here's the culprit:

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:

Analogies

I'm being a bit tongue in cheek here, but at the same time I'm sure there is something to be learned from this video in relation to the sea ice in the Beaufort, Chukchi and East Siberian Seas:

 

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.