I haven't been making many animations this year as, unfortunately, there are only 24 hours in a day. Two weeks ago the ice arch at the southern end of Nares Strait collapsed. Even though we have seen how it works last year, the relatively clear images of the area in the past two weeks prompted me to make this animation that shows how all of the fast ice in Nares Strait quickle disintegrates after the collapse of the ice arch.
The animation starts on June 26th (day 178) and ends on July 10th (day 192):
It looks like transport from the Arctic Basin got underway 11 days after collapse of the southern ice arch, three days later than last year.
Ice transport through Nares Strait contributes to ice loss from the Arctic Basin. It it isn't quite as significant as ice transport through Fram Strait (roughly 10% at the most), but the ice that gets transported, is some of the thickest and oldest ice in the Arctic. A NASA-led study by Ron Kwok in 2010 (PDF) showed that transport in 2007 was exceptionally high:
To quantify the impact of ice arches on Arctic Ocean ice cover, the team tracked ice motion evident in the 13-year span of satellite radar images. They calculated the area of ice passing through an imaginary line, or "gate," at the entrance to Nares Strait. Then they incorporated ice thickness data from NASA's ICESat to estimate the volume lost through Nares.
They found that in 2007, Nares Strait drained the Arctic Ocean of 88,060 square kilometers (34,000 square miles) of sea ice, or a volume of 60 cubic miles. The amount was more than twice the average amount lost through Nares each year between 1997 and 2009.
Read the whole article here.
60 cubic miles is 250 cubic kilometres, so if I'm not mistaken the ice that was transported through Nares Strait in 2007 was on average 3 metres thick. No spectacular numbers, but the break-up and subsequent ice transport through Nares Strait remains a spectacular sight nevertheless.
Great animation, Neven!! Right now, the mass of ice blowing out the Fram does dwarf this, but the Nares will indeed drain much of the rest of the thickest ice of the arctic basin.
Off-topic for the Nares strait, but on-topic for melting ice in general is the latest changes in those Siberian fires. Over the past 48 hours, the size of the fires along the Aldan River (top right image of the arctic mosaic) has gone from serious, to absolutely alarming.
Here are two images, about 48 hours apart. For a sense of scale, the rectangular-shaped loop in the river seems to be about 15 km wide, by my estimation. Previously-burning areas are obviously much worse, but off the field are more areas of frightening extent.

It's all been blowing north, towards the Arctic basin. Untold hundreds of tons of soot on an express to the ice...
Posted by: Steve C | July 11, 2012 at 17:27
I suspect fires/soot are a two-staged process.
The reason I suspect that is because yesterday I checked my battery charge (I'm off the grid) and noticed that I was well under what I normally have by that time in the morning.
I went outside to check my panels (see if weeds had grown up overnight, large flock of birds had visited). In spite of it being forecast to be our first hot day of the summer the Sun really didn't feel hot.
Took a look to the east and clearly there was smoke in the air. Checked and we have a fire burning a couple hundred miles from here.
While that smoke is blowing over I would expect solar gain to drop. When the soot settles, then heating is going to get boosted.
Posted by: Bob Wallace | July 11, 2012 at 19:29
Shortly after I wrote my note on July 5 (June post on Nares) when I suggested a large floe (80 km diameter) might keep ice from leaving Kane Basin for a while, the huge floe broke up. The biggest remaining pieces are about 20 x 30 km and 25 x 50 km in size, and they appear to have slowed ice from exiting the Kane Basin. The smaller floe (20 x 30 km) is now fully in Smith Sound, and moved about 20 km in the last three days and another 20 km during the previous 4 days. Smaller pieces from the original large floe (such as one 5 x 10 km in size), however, have moved about 60 km in the past 3 days, and 80 km in the previous 4. The largest remaining piece (25 x 50 km) remains in the Kane Basin and has moved about 5 km in the past 3 days, but not toward Baffin Bay, merely toward the center of the Basin at the edge of Smith Sound. During the previous 4 days, it did move 10 km toward Smith Sound. Once these two large floes get through Smith Sound into Baffin Bay, Kane Basin will have an opportunity to flush (although new ice will always be entering from the other end). If these large floes are also very thick, are they getting snagged on the bottom? Or does the surface water just flow much faster than deep water? Or is wind blowing the “small” floes?
Posted by: Tor Bejnar | July 15, 2012 at 07:12
Yesterday happened to look up Nares/Kane and compare some MODIS images and noticed one floe, middle of it all to be stationary. It was white alright. This morning looked up Google Earth and found there to be 3 islands in the channel. One carried the name "Hans Island" (photo on GE) to get an impression, and from the shade of the others, the one I noticed as the most southern of the 3, are pretty high up.
From the big glazier break off that was initially some 240km2 or so and drifting out, suspect those waters are deep. Here http://www.earth.ox.ac.uk/~helenj/at_sea.html is mentioned the instruments sitting in depth ranges from 30 to 200 meters. 20 meters I'd venture to be deep enough to pass anything but maybe icebergs. Nares has a sill depth of 250 meters and here http://www.tos.org/oceanography/archive/24-3_muenchow.html mentions depths up to 366 meters. Little chance of grounding it seems.
Posted by: Seke Rob | July 15, 2012 at 08:43
I know that the Nares Strait is deep, but any body of water, especially one with islands, might have submerged islands on which floes could get grounded. I just don't know the bathymetry of Kane Basin/Smith Sound.
When I first detected movement of ice in Kane Basin, a day or two before the bridge started serious collapse, I noted that ice in the center of the basin was moving "upstream". Although eddies are expected, I wasn't expecting them so close to the exit, affecting the last large floe in Kane, as it appears to be doing.
Posted by: Tor Bejnar | July 15, 2012 at 16:25
Urgent! Please read: Arcticicelost80 on ASI 2012 update 7: steady as she goes
Posted by: Espen Olsen | July 16, 2012 at 18:28
I had expected lots of ice flowing through Nares Strait once the ice bridge broke. But almost no ice has left Kane Basin in the past week (since the 20x30 km floe exited), even though ice already in Smith Sound is flowing away at about 5 km/day. Within the Basin, the ice is slowly moving in a counter-clockwize gyre. This includes the largest floe near the mouth of Kane Basin that is currently moving eastward (back into the Basin, away from Smith Sound) at 1-2 km/day.
Several days ago I hypothesized that the largest floe might possibly be grounded when it was near the Canadian edge of Kane Basin near Smith Sound, as it wasn't moving toward the "exit" like its neighbor floe did. As of yesterday (lots of clouds today), the floes and ice melange are mostly sticking together (hiding most of the floe edges) - it is all obviously marching to the same drummer (the gyre), and therefore not grounded. Will ice get pushed into Smith Sound only after Kane Basin is filled with ice? (And there is not much ice movement in Nares Strait north of Petermann G., so this might take a while.)
Posted by: Tor Bejnar | July 20, 2012 at 03:34