Nares Strait 2012 Ice Arch Collapsing

It looks like the ice arch in at the southern end of Nares Strait has started to collapse, according to yesterday's satellite image from LANCE-MODIS:

This break-up is occuring 10 days later than last year. Back then it took about two weeks for all of the ice to start moving across the entire strait and transport from the Lincoln Sea to get underway. Looking at the weather forecasts and the fact the ice is blue and breaking up at the other side as well, I don't think it will take much longer. High time too, as Baffin Bay has almost run out of ice.

But if you want to know the real deal about Nares Strait, I urge you to go to the Icy Seas blog. This blog is run by sea-going physical oceanographer Andreas Münchow, who has actually been to Nares Strait and will soon go back there to retrieve all kinds of gadgets full of data on ice thickness, volume flux and what not. He graciously allows me to re-post his latest blog post:

Nares Strait 2012 Ice Arch Collapsing

The collapse of the ice-arch in southern Nares Strait began June-27, 2012 with development of a small hairline fracture along the western side of the strait off Ellesmere Island, Canada. The fracture connects an isolated area of open water off Bache Peninsula, Canada at 79 N latitude. The front between land-fast ice in the north and the open water in the south has moved slightly southward. It has also lost a visible larger piece of ice that before anchored the bridge at its western connection to land. This motion will open the hairline fracture more, accelerating the collapse of the ice-arch. The missing support of the ice-arch on its western side will collapse the entire ice-arch and the previously land-fast ice of Nares Strait will stream rapidly to the south, I predict, before this weekend.

Updates (including an animation) will be posted daily at http://muenchow.cms.udel.edu/Nares2012/Kane/.

Ice-bridge at southern Nares Strait June-26, 2012 23:30 UTC from MODIS-Terra. There are no hairline fractures yet along the Ellesmere Island side near 79 N latitude. Greenland is on the right (east), Canada on left (west).

Ice-Bridge at southern Nares Strait on June-27, 2012 17:40 UTC from MODIS-Terra. Notice the crack and hairline fractures in the ice along the Ellesmere Island coast near 79 N latitude and 75 W longitude.

This collapse happens each year in the summer, though the timing varies from April for weak and July for strong arches. The arch in 2012 lasted longer than the one in 2011. No or only weak ice-arches formed at this site in 2007, 2008, and 2009, e.g., http://muenchow.cms.udel.edu/MODIS/.

Read the whole thing and comments here.

Comments

[Neven]

Speaking of collapses, the fast ice between the Lena Delta and the New Siberian Islands is totally disintegrating, same time as last year.

[www.facebook.com/profile.php?id=687386516]

The ice bridge has collapsed today.

http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=crefl1_143.A2012181005500-2012181010000.500m.jpg

[George Phillies]

I am extremely grateful to you for finding this, but in this 'covers several screens each way' document I am not sure what I am looking at.

For the benefit of those of us who are a bit slower at aerial reconnaissance, could you possibly be persuaded to say roughly where in those beautiful photos the ice arch is? Thank you.

[crandles]

It just about the centre of the image.

North is down and to the left if that helps your orientation.

[crandles]

_

[me.yahoo.com/a/nSjChi4X3vr8X3DRw93GkY1.cerja.8nvWk-]

The piece that's broken away is the white triangular piece suurounded by blue sea, yesterday that gap on the upper right was just a crack.
Phil.

[me.yahoo.com/a/nSjChi4X3vr8X3DRw93GkY1.cerja.8nvWk-]

Here's a detail from this mornings Aqua image, you can see the development from the shot that Neven showed at the opening of this thread.

Phil.

http://i302.photobucket.com/albums/nn107/Sprintstar400/Icearch.jpg

[Neven]

George, there are two ways to check satellite images (three ways actually).

The easy way is by going to the LANCE-MODIS Arctic Mosaic. The Mosaic is divided up in quadrants that you can click on. Once you do that, you can choose what resolution you want (1 km, for instance, means that every pixel is 1 km). By default images from the Terra satellite are shown. You can however also opt for images from the Aqua satellite, which has the images a bit earlier than Terra.

Arctic.io also has a special webpage that allows you to zoom in and out (no quadrants). Make sure you have the date right. Once you have zoomed in to where you want to go, you can actually save a permalink that you can paste anywhere you want to show people something you saw (example: Svalbard today).

The final option is the most interesting if you want satellite images hot off the press. This is where that link in the second comment leads to: the MODIS near real time (orbit swath) images. You see everything first here, but it takes a bit of practice to get the hang of it.

Patrick Lockerby wrote a tutorial about this two years ago: MODIS Rapidfire for citizen scientists. The best way to learn how it works with these satellite images is to just play around.

These images are one of the greatest gifts from the Internet. Who would have thought 10 or 20 years ago that mere mortals would be able to look at the Earth in near real time?

[Espen Olsen]

Neven:

I appreciate you mentioning our mentor Patrick Lockerby, who by the way was the first to tell the world about the big Petermann calving a few years ago,although someone else grasped the honors, I wonder what Patrick is up to, but I for sure wish him all well. Regards espen

[Neven]

Well said, Espen.

[crandles]

A fourth option for images around Greenland is to go to
http://ocean.dmi.dk/arctic/kane.uk.php
to get a choice of about 6 images per day.

[George Phillies]

I am profoundly grateful to all of you for all the advice. For those of you looking at the big picture, is is on the left side of the screen, about half way down, and the breakaway is I gather moving from left to right.

On Phil's gorgeous morning shot, note also the fine additional line behind the breakup. It starts at the bottom of the screen, a bit to the right of center, and heads off in the two o'clock direction.

[George Phillies]

Indeed, Crandles has another superb link, for example the

http://ocean.dmi.dk/arctic/Ittoqqortoormiit.uk.php

Ittoqqortoormiit
MODIS/AQUA
2012-06-28

shot, where the ice on east Greenland has pulled away entirely from the coast, and if you look at the upper left corner of the shot you can see what appear to be cracks forming at the inland end of the fjord (or whatever it actually is).

It's incredibly neat, but I lack the time.

[Account Deleted]

continuation
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c02.2012182.aqua

[Neven]

That's a nice and clear image!

[Greg Wellman]

With the arch broken, looks like Kane Basin won't take too long.
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r03c02.2012183.terra.1km

[Yazzur]

Today, Modis has a very good image of the ice in Nares Strait coming apart:

http://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=crefl1_143.A2012184012500-2012184013000.250m.jpg

[Tor Bejnar]

Today, MODIS shows that Nares Strait ice is breaking in front of (even up "stream" of) Pettermann Glacier. The Kane Basin, per DMI's Greenland Images site, is full of floes working their way southward. The one huge floe might stop traffic for a while!

[Christoffer Ladstein]

The Narwhales on the other hand will like this, thus being able to travel further north:-).

[Shortfatape]

Anyone else really curious about what happens with that big crack on the Petermann this summer?

[Seke Rob]

hrmmm http://ocean.dmi.dk/arctic/kane.uk.php

Push Kane and Kennedy cadres to see traffic flowing, but Lincoln is still stuck at the tail end from what I can see for the 5th.

[I Ballantinegray1]

Is it me or is there an awful lot of open water compared to the amount of 'space' the final collapse of the southern arch provided?

I'm sure we have all been monitoring the collapse and so know that it's been slow and painful on it's arrival meanwhile the ice between the 'Peterman arch' and the southern arch has just vapourised?

I only mention this as I'm tending toward using 'Nares' as a guide to the breakup of the NW Passage and from what I think I'm seeing here we can expect a lot of the ice in the passage to also melt out and not be dependant on being 'shipped out' to clear the channel?

Broadening this further I have to wonder at the state of the F.Y. ice in the basin as a whole. how close must we now be to it's complete melt out in situ?

[Christoffer Ladstein]

The weather in the Canadien Acrchipelago lately have been just insanely hot, watching through the eyes of MODIS, the contrast between the barren snowless (soon also iceless if this continues...)land and the still mostly icecovered straits, just is baffling!

So I tend to agree with you, Ballantinegray1, much of the ice will just melt down in situ.

Still, albedo and weatherregime in Nunavut & Northwest Territories are not comparative to the conditions closer to the pole...but alas, the ice is thin and "winds of change" and currents may prove me wrong;-).

[me.yahoo.com/a/nSjChi4X3vr8X3DRw93GkY1.cerja.8nvWk-]

Not only has the ice in the Nares strait broken up and is starting to flow south but today the ice at the mouth of the Petermann glacier has started to breakup.

Phil.