« Northern Sea Route almost open | Main | Death of a webcam »

Comments

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

Artful Dodger

Olga Strait, a lovely name...

Seke Rob

Looked at Google Earth 3D where the deep trench is apparent as Fram takes off at the North Eastern tip of Greenland. Who knows is that an underlying part of the ''New Polynia'', causing phenomena reoccurring with regularity.

Neven

Ah yeah, Olga Strait. Thanks, Lodger!

Artful Dodger

De nada, Neven. Hat tip to our friend Jack Taylor from Sep 2010 for the original hint!

Alan Wallcraft

ACNFS is predicting increased ice drift through the Fram Strait this weekend.

2011072118_2011072400_arcticicespddrf

It was quite different this time last year 2010072318_2010072400_arcticicespddrf

Seke Rob

As for location, is the current location in this map i.e. is webcam 1 / 2 same as noaa1/2?

http://psc.apl.washington.edu/northpole/DriftTrackMap.html

Neven

I'm quite sure it is, Seke Rob.

Thanks for posting those two images, Alan. I'm in the process of describing the differences between this year and last year for a new SIE update.

Chris Biscan

even with it slowing you can see the edge of the ice fraid.

Paul Klemencic

This year's ice pack movement really teaches us a lot about how the pack spreads and contracts, almost similar to breathing. Your animation of the Fram Strait shows the ice export from July 18 until about July 23. Then the ice moves the other way, and open water appears and grows between the pack and Greenland's east coast. I see you commented on that, and this set of animation really shows it well.

Philiponfire

I have been paying attention to the MODIS pictures of this area for the last two weeks and transport seems very slow to me. how fast or slow does it get can someone give me numbers please.
for example if you look at 1st August and then blink with today 5th august focused on the large area of fast ice about 20 miles east of where the large piece of fast ice has cracked off two days ago you will see a train of three 6-8 mile diameter ice floes. in 4 days one has basically not moved and the caboose has moved about 10-12 miles south east. so is that fast or slow?

An animation would be most interesting.

Bob Wallace

How does one 'see' the directional movement in the animation. Clearly things change. But from frame to frame I can't tell if ice is moving out and melting or if it is sloshing back and forth.

I have to take the transport-out part on faith anchored to the flow charts. Perhaps there's a trick I need to learn?

Wouldn't it be great if we had 'tracking collars' on come individual hunks of ice and could watch their movement (and melt) as time goes along?

--

And another question that's been bugging me. Why does the ice tend to cling to the Greenland coast? Is there a prevailing wind or current? Or is it that any ice which makes it's way further east gets melted?

Neven

Argh, I can't believe I forgot to press the Save button.

The next three days of the animation will be up in a minute, Bob. You'll clearly see the ice pack expand towards Fram Strait.

Bob Wallace

I guess I'm dense. I can see concentrations change and if I assume movement out and melting I can make what I see into movement out and melting.

But shown the animation without context and extra chart information I don't think I would see anything but colors rearranging themselves.

Perhaps if I saw the area above the frame top emptying out/moving in that direction.

I suspect most people would want to see Joe Ice and Jane Ice heading out the door and fading away into melted ice. I have no idea how to display what is happening in a way that would get the message across.

Except, is there a reliable measurement of actual current/flow through the Straight? If so, might that be overlayed in the form of a directional arrow something like the speed/drift charts.

Overall, it's no big thing. I appreciate seeing that things are in flux and not static. I can get the other info elsewhere...

Bob Wallace

Here's something that helps me see it better...

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=08&fd=01&fy=2011&sm=08&sd=06&sy=2011

A CT comparison of 8/1/11 and 8/6/11. The heavy concentration (lavender and purple) ice is moving toward the Straight. If a bunch of that gets pushed through volume is going to get hurt.

Neven

Bob, try to focus on the edge of the ice and ice pack as a whole, don't let yourself get distracted by the changing colours (that's mostly an artifact). From August 1st onwards you see the ice pack starting to move in a southwest direction. You can actually see the edge of the ice pack bumping into Svalbard (the big green archipelago in the middle).

Looking at the ice extending southwards along Greenland's eastern coast is not a good indicator either, because that far South the ice floes will melt out. So focus on the edge of the ice pack further North extending from Franz Josef Land to the north of Greenland.

Here's an animation from last year August 10th-September 2nd showing the transport towards Fram even clearer.

Artful Dodger

Bob: watch the ice edge to detect movement. It's characteristic shape tends to be preserved as the pack moves.

You asked "Why does the ice tend to cling to the Greenland coast?". This is called 'fast-ice', which is short-form for land-fast ice. Fast ice tends to be thicker and grounded on land, so it behave differently during the melt season.

Finally, 'tracking collars' do exist for sea ice. They are called 'drift buoys'. There is a map of drift tracks on Neven's Daily Graphs page (see above).

I hear Neven's next movie will be titled: "Fast and Furious 11: Longyearbyen Drift"

;^)

Bob Wallace

Thanks guys. I'll see if I can train my eyes.

Twemoran

I tend to look for a large, oddly shaped chunk and try to follow it backward in time using lance-modis.

I've found much of the ice near Greenland to be stuck in gyres when the flow is strong and to head east at quieter times (probably due to katabatic winds.

BTW a spring tide is due tomorrow that may release a little more of the fast ice.

Philiponfire

Bob look at the modis images. there are enough identifiable floes to be able to see movement or lack of it.
there has been some movement south in the last ten days and some circling. the fastest floes I have identified are moving at about 10km per day.
assuming a 150km wide front and average thickness of 1.5M and 75% ice cover I get about 1.75cubic kilometres of ice moving south per day

Artful Dodger

that ain't transport, that's a freight train!

Bob Wallace

Easiest (for me) to see if one watches the very large melt pond which starts on the NE tip of Greenland and gets shoved down-island.

Do wish researchers had the resources to drop buoys onto the ice pack as it moves out. Getting there would be the cost, a simple GPS transmitter would be cheap.

Perhaps researchers are doing satellite tracking and we don't get to see that data.

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