It looks like I'm back just in time to witness the breaking up of the ice plug in Kane Basin. This just in from the Aqua satellite:
It's a bit vague, but it looks as if the lower part of the plug is crumbling. If it is breaking up, how long will it take for ice transport to get going through Nares Strait?
This page will be updated the coming few days. Stay tuned...
Update June 18th
First thing I did today, was look at the MODIS near real-time gallery. Another murky image from the Terra satellite shows that the ice plug is still holding up! It seems that just another large layer has been peeled off the icy onion blocking the south end of Nares Strait:
Hopefully Aqua will give us a better view later today.
Update 2 June 18th
Aargh, I'm really out of shape. What I thought I saw in the real-time image above was just those small floes breaking off near the Greenland coast. But in fact this is the backside of the huge ice plug breaking away!
This can be clearly seen on today's ENVISAT ASAR image (available at DMI):
I also overlooked the big crack that was forming on the 16th (silly me):
Update 3 June 18th
And here it is, definitive confirmation:
Okay, so we're back to my initial question: How long will it take for ice transport to get going through Nares Strait?
Either way, it's animation time...
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!
Posted by: Christoffer Ladstein | June 17, 2011 at 22:41
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?
Posted by: idunno | June 18, 2011 at 03:31
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...
Posted by: idunno | June 18, 2011 at 04:52
Idunno, it's too cloudy to tell for now, but the nose knows it goes (sooner or later).
Posted by: Neven | June 18, 2011 at 08:40
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.
Posted by: idunno | June 18, 2011 at 09:44
It looks like Aqua will give us a reasonably good view later today. Time to prepare for animations. :-)
Posted by: Neven | June 18, 2011 at 14:48
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.
Posted by: Lord Soth | June 18, 2011 at 15:12
Very clear view of the fracturing Nares arch today:
http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r03c02.2011169.terra
Posted by: L. Hamilton | June 18, 2011 at 22:54
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/
Posted by: Leif Ratinger | June 18, 2011 at 23:45
@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...
Posted by: FrankD | June 19, 2011 at 02:08
Thanks for all the info, Leif!
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.
Posted by: Neven | June 19, 2011 at 09:05
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. :-)
Posted by: Neven | June 19, 2011 at 11:07
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
Posted by: Lord Soth | June 21, 2011 at 03:46
The couple with canoes headed for the north pole has turned around due to the ice conditions (to little open water) and slow progress.
Posted by: Oslo | June 22, 2011 at 11:14