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Christoffer Ladstein

I'm rather stunned to see that last winters snow is already gone on the Greenland side....
Must have been less precipitation than normal? If yes, that's bad news for the glaciers!

idunno

Hi Neven,

During your hols, I found a new (to me) source of satellite images at:

http://www.arctic.io/

... which are sometimes useful for cross comparison.

@Christoffer - I'd also been wondering about whether precipitation is below normal, but in other places.

The amount of blue ice has already been discussed, on SIE 7, and elsewhere. On the latest satellite, there are large patches of this blue, translucent ice in the Archipelago, the East Siberian sea and elsewhere. They are showing up on the CT map as very low ice concentration, when the satellite seems to show that the sea is actually about 100% ice-covered.

One possible explanation seems to be that the ice in these regions is entirely bereft of snow-cover?

idunno

Hi Neven,

It looks like there may have been, on 17 June, a fairly spectacular collapse of the land-fast ice on the far side of Greenland, greatly widening the entrance to the Fram Strait between Greenland and Svarlsbard.

If you can find the feature which looks rather like a nose, in profile, on 16 June and before; by the 17th, it looks like the most spectaculat sneeze in history. Or a very bad case of leprosy? The terminal stages of syphilis?

Who nose? Not I...

Neven

Idunno, it's too cloudy to tell for now, but the nose knows it goes (sooner or later).

idunno

Hi Neven,

Yeah, double checking on the infra-red pictures, I think I've been deceived by a cloud formation and tommorow will possibly show the first known instance of nasal reconstructive surgery in the High Arctic.

Neven

It looks like Aqua will give us a reasonably good view later today. Time to prepare for animations. :-)

Lord Soth

There is to much cloud cover but about a week ago when we had the last clear image, there was a large east west crack midway in the Kane Basin, so with the Ice Plug gone, there should be a fairly quick fracture of the rest of the Kane Basin.

On another note, for those following the Pettermann ice island, the Canadian did an update a day ago at:

http://www.ec.gc.ca/glaces-ice/default.asp?lang=En&n=D32C361E-1&wsdoc=B6A3209E-2513-426E-A1AD-08BB8BFA399F

The largest ice island is 58.5 sq km. This will be quite a tourist attraction if it avoids getting stranded on the remaining banks, and make it into down the Newfoundland Coast.

Leif Ratinger

The fractured part is mostly first year ice that formed after the ice bridge had been established.

http://ice-glaces.ec.gc.ca/prods/WIS55CT/20110613180000_WIS55CT_0005856255.gif

Note that the map (from Monday) already shows some mobile ice in SE Kennedy Channel. However, it may take several weeks until all of Nares Strait has fractured.

NAIS forecast from Thursday says: "Near mid-July, some of the fracture events will occur over Pond Inlet, in northern Admiralty Inlet, in western Barrow Strait and in Kane Basin."

http://ice-glaces.ec.gc.ca/prods/FECN16G/20110616000000_FECN16G_0005858072.pdf

The map, valid 2011-07-15, shows mobile ice all along Nares Strait, but just bergy water south of it, meaning no ice transport. The seasonal forecast had complete fracture of Kane Basin around 16-18 July.

http://ice-glaces.ec.gc.ca/prods/ARCTIC001/20110602000000_ARCTIC001_0005834825.pdf

Weather forecast for the next week suggests little clouds, much radiation, rather high temperatures and even moderate winds at some days. But spring was quite cold and ice that has been consolidated for months won't collapse easily.

http://deponie.bplaced.net/arctic/gfs.2011-06-18.12z/

FrankD

@Neven: How long will it take for ice transport to get going through Nares Strait?

Couldn't even guess a number of days, but it seems to me that - not considering "ice jams" forming at choke points - there are probably only two points where the clearing process can be delayed. The recent fracture occurred in a pretty nice arc, creating a new bridge even as the old bridge collapsed. The new bridge is nearly twice as long as the old one, so you wouldn't think it would last long (although its shape distributes the load to the buttressing headlands better than the old, flatter arch). I personally don't think it will last that long, but I'm not a civil engineer so its just IMO.

Behind that there is no decent anchor point in Kane Basin, so the next place a bridge could form would be much higher. There is a fair bit of ice to clear from the Kane Basin so that can't flush out overnight - perhaps a week or two to clear, depending on weather.

Again, just IMO, but I think the next pair of butresses that could support an arch are at the bottom end of Kennedy Channel. But when you look at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r03c03.2011169.terra (Zoom to 250m) this area is already fragmented, so nothing is going to form there.

Franklin Island appears a good spot for a new arch to form - indeed that same MODIS pic shows that a rather assymetrical arch in already in place. That is probably the last point a bridge could form. The area at the mouth of the Petermann Glacier is a good buttress, but is so close to the mobile ice in the Lincoln Sea that I don't think any plug could last long, as it would be subjected to a lot of dynamic stresses.

I'm sure a civil engineer could give you some numbers...

Neven

Thanks for all the info, Leif!

Again, just IMO, but I think the next pair of butresses that could support an arch are at the bottom end of Kennedy Channel. But when you look at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r03c03.2011169.terra (Zoom to 250m) this area is already fragmented, so nothing is going to form there.

Franklin Island appears a good spot for a new arch to form

Indeed, Frank. On today's MODIS (real-time) image it appears that the ice around Franklin Island is already fragmenting big time.

I think everything from Smith Channel (where the ice plug has finally conceded) to Kennedy Channel (where Franklin Island is) is going to fragment rather quickly, perhaps in a week or 10 days. Here's an image with all the names in the Nares Strait.

The rest of the frozen mass between Kennedy Channel and the Lincoln Sea - which looks a bit stronger - will probably follow soon too. I give it two weeks, tops, for things to be on the move in the whole of the strait. I base this on the forecast of a high pressure system in the area, meaning high temperatures and clear skies, combined with a strong current (I don't know if it is).

But there's some thick ice involved and indeed, that second arch looks pretty solid for now. The plug held out much longer than I expected as well, so it might well take longer than 2 weeks. We'll see.

I'm going to turn this into a decent animation today, so we can check progress.

Neven

I think this year's situation can be compared quite well with 2006:

June 30th 2006

7 days later

16 days later

Clouds, clouds, clouds...

27 days later

Two weeks for transport to start from the Lincoln Sea is tight, but possible.

I think. :-)

Lord Soth

The latest shows the Kane Basin fracturing further from the north to the south. It only took a few days and now a good portion of the Kane basin has started to fracture.

http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r03c02.2011171.terra.250m

Oslo

The couple with canoes headed for the north pole has turned around due to the ice conditions (to little open water) and slow progress.

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