« Sea ice extent update 20: spread it! | Main | Sea ice extent update 21: 7 million mark passed »

Comments

Feed You can follow this conversation by subscribing to the comment feed for this post.

Artful Dodger

Hi Neven. The "big grey band" on the Uni-Bremen concentration map represents data for a satellite pass that has not been received yet. These images are built up in real time, so if you visit the site throughout the day you'll see more and more swaths added to the current map.

Aqua's orbital is period 98.4 min, so the new map should be updated within say, an 2 hrs, +/- 30 min.

Neven

Thanks, AD. I'll update it first thing in the morning.

Andrew Xnn

Neven;

Thanks for doing all this work.
2007 and 2010 both appear unique in their own ways.
2007 looked to be more compact, but also more dense.
2010 appears to have much more colored areas of thinner coverage.

I've been researching the Arctic Dipole Anomaly and it's role.
As some realize, the Dipole was present back in June.
However, over the last few years it's actually been a fall phenomium.
That being the case, if it sets up again, we may be in for another round of rapid changes considering how much more mobile the pack appears to be this year compared to the past.

Here's one of the better links I've found about the dipole:

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=1398

and another link/paper (not as good):

http://www.agu.org/journals/ABS/2006/2006GL028112.shtml

siili

Todays preliminary Bremen passive microwave image should be a very good example of the problem with what i assume is high clouds made up of ice? Any metereologists/remote sensing people in the forum?

In the Beaufort sea there is extensive melt going on with very scattered ice as has been seen in the few clear days in visible images and yesterday and the day before that in micro as well.

Yet in todays image, the concentration is close to 100% and the iceedge sharp as a knife, giving a binary open water/ice with nothing inbetween.

In visual images the area is covered with clouds that appear epecially white and in the infrared band pink compared to ordinary clouds which are white and the ice which is red.

So we could be in for a noisepeak in tomorrows area estimate and perhaps a sharp drop in extent?

Anu

Speaking of sea ice concentration, the ice bridge by Severnaya Zemlya (connecting to the Taymyr Peninsula), which is currently the only sea ice blocking the Northern Sea Route (North East Passage) looks close to melting through:
ftp://ftp-projects.zmaw.de/seaice/NEAR_REAL_TIME/NSR_latest_large.png

Once the sea ice concentration turns blue (about 25% or less) that means the top melt and bottom melt are pretty advanced - since it is still July, I bet the ice bridge melts through within the next week. Winds can rearrange the ice, but I think it is just a matter of time before it opens up. There is a narrow backbone of more concentrated sea ice along the ice bridge, but surrounded soon by open water on two sides, it should melt fast.

Neven

Yet in todays image, the concentration is close to 100% and the iceedge sharp as a knife, giving a binary open water/ice with nothing inbetween.

That's exactly what I mean what I said 'blinking flash light'. CT seems to be a bit more consistent.

Anu, that's good news for our Norwegian friends who are heading that way.

Neven

Still cloudy in the Canadian Archipelago, but the ice in those straits and seas that are in contact with the multiyear ice is cracking up nicely.

Artful Dodger

Hi Anu. I was looking at the Severnaya Zemlya ice bridge issue last night. 2010 is now closest to Aug 16, 2008. This year, the strait is clearing mostly from the Atlantic side and should open by about Aug 5.

2008 is the only previous year where there was no landfast ice North of Severnaya Zemlya at the annual minimum. If this recurs this year, the granular 2010 pack ice will move freely with the transpolar drift and prevailing winds.

The Great Circle distance between Severnaya Zemlya and Svalbard is 1435 km. At a drift rate averaging 30 km / day, that is just on 7 weeks (48 days) for an ice floe to transit that distance.

If the Arctic Dipole Anomaly (DA) returns in force as Andrew Xnn suggests above, we could see dramatic sea ice advection through Fram Strait this Fall.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment