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Author Topic: Fragmentation Event. Will it have impact over the summer melt season?  (Read 139628 times)


crandles

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #101 on: March 26, 2013, 11:58:35 PM »
I could well have been wrong to include 'East Siberian' and 'thick' in my last post. I think it may be that these Ascat images show light grey for MYI because/where surface is uneven. Thus the images may not say much about thickness except by the implication that MYI tends to be thicker. Or maybe I am wrong now. Hopefully someone more knowledgeable about interpreting these images will clarify.


John Batteen

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #102 on: March 27, 2013, 06:15:22 AM »
The cracking has grown dramatically over the last two days.  Anyone else noticing this?

Dromicosuchus

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #103 on: March 27, 2013, 07:02:25 AM »
Honestly, John, it's getting hard for me to keep track of it at this point; the fracturing is becoming so extensive that it's difficult to tell what was there before and what's new.  That said, I have noticed a recent crack that's arced out from New Siberia on the Russian side of the Arctic.  I'm not sure whether that's normal or abnormal for this time of the year, though.

ChrisReynolds

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Juan C. García

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #105 on: March 27, 2013, 10:43:39 PM »
Some polynyas that are showed from AMSR2 (Bremen):

It is too early, isn't it? And at several places of the Arctic...
http://www.iup.uni-bremen.de:8084/amsr2/
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Jim Hunt

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #106 on: March 28, 2013, 02:48:15 AM »
For a close up view of the "Banks Island Polynia" see also:

http://econnexus.org/bigger-cracks-than-ever-in-the-beaufort-sea-ice/

It is too early!
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

crandles

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #107 on: March 28, 2013, 12:20:56 PM »
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2013086.terra.367.4km

Has to be really dark and not just red to be open water. (Or white cloud over really dark area.)

Jim Hunt

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #108 on: March 28, 2013, 02:22:06 PM »
It would seem to pass the "A-Team test", on the 26th at least?



Reality is merely an illusion, albeit a very persistent one - Albert Einstein

ChrisReynolds

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #109 on: March 28, 2013, 06:52:25 PM »
I think that Polynya probably was open water.

However in the true colour MODIS for yesterday, 250m resolution, the open water is ice covered.
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?subset=Arctic_r04c02.2013086.terra.250m

And in yesterday's IR that I posted above there is what looks like a large amount of low warm cloud/fog streaming from the polynya.
https://docs.google.com/file/d/0B3pB-kdzoLU3b3VzTHpNRFNVSDQ/edit?usp=sharing
URL corrected.

The latest IR suggests a reduction of this humidity flux.
http://www.weatheroffice.gc.ca/data/satellite/hrpt_dfo_ir_100.jpg

Regional pressure fields suggest that winds would be from Banks into the Arctic, supporting my interpretation of a moisture plume.
http://www.wetterzentrale.de/topkarten/fsavnnh.html
« Last Edit: March 28, 2013, 07:11:46 PM by ChrisReynolds »

HeisenIceBerg

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #110 on: March 28, 2013, 07:07:44 PM »
Looks like a pretty long crack has opened up over the past two days just east (above in Worldview) of the islands separating the Laptev and Kara Seas.  No crack visible through the clouds on the 26th, first noticeable on the 27th, and wider on the 28th.

Mar 27: http://earthdata.nasa.gov/labs/worldview/?map=486752,-53312,1885536,575424&products=baselayers.MODIS_Terra_CorrectedReflectance_TrueColor~overlays.arctic_coastlines&time=2013-03-27T12:00:00&switch=arctic

Mar 28: http://earthdata.nasa.gov/labs/worldview/?map=486752,-40000,1885536,562112&products=baselayers.MODIS_Terra_CorrectedReflectance_TrueColor~overlays.arctic_coastlines&time=2013-03-28T12:00:00&switch=arctic

Also, correct me if I'm mistaken, but it looks like the ice just west of the islands (below in Worldview) is younger, thinner ice.

One last thing.  Chris, I'm not sure if this is just for me or if others are experiencing this, but I can't access the docs.google.com links that you've posted.  I get the message,

"You need permission to access this item.

You are signed in as [my google account email], but you don't have permission to access this item. You can request access from the owner or choose a different account."
The HeisenIceBerg uncertainty principle of climate science: The less sure climate scientists are about something, the more sure climate deniers are that it means climate change isn't happening or doesn't matter.

The converse is not true.

ChrisReynolds

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #111 on: March 28, 2013, 07:10:46 PM »
Heisenberg,

Fixed now, just in case the URL has changed here it is.
https://docs.google.com/file/d/0B3pB-kdzoLU3b3VzTHpNRFNVSDQ/edit?usp=sharing

frankendoodle

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #112 on: March 30, 2013, 01:05:32 AM »
If nothing else, these fissures illustrate just how thin to non-existent the ice sheet is on the Eurasian side.  It reminds me of all the fissures last summer just before the great arctic hurricane of 2012. (I'm not implying that a storm like that is going to happen now)
http://ice-glaces.ec.gc.ca/prods/MODISCOM-F/20120806000000_MODISCOM-F_0006580948.jpg

I don't think these cracks will have any impact on the summer melt. I think they show just how susceptible the ice sheet is to currents now that it is mostly first year ice.

Apocalypse4Real

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #113 on: March 30, 2013, 05:42:07 AM »
Nasa Earth Observatory has just put up a new report on the Beaufort Sea Ice Collapse. Interesting to see Meier's comments.

http://earthobservatory.nasa.gov/IOTD/view.php?id=80752

sofouuk

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #114 on: March 30, 2013, 09:28:51 AM »
also interesting to see nasa routinely linking to neven!  :P

Sigmetnow

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #115 on: March 31, 2013, 12:27:03 AM »
I’ve been practicing my animations....  Here are views of North East Greenland ice as it fractures and moves south.  Just 5 pics (to keep file size down), between Feb 24 and March 22, 2013.  I’ve set them to run rather slowly.  Note the (temporary) refreeze on the two concave sections.
People who say it cannot be done should not interrupt those who are doing it.

TerryM

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #116 on: March 31, 2013, 07:25:17 PM »
Arctic.io has his Split Zoom feature up and running. This is the most accurate as well as the easiest method of comparing change over time of Arctic ice during the melt season.


I won't get into the details here, but urge everyone to try it out. The learning curve is short to nonexistent & the results are spectacular. It shows two MODIS images side by side that can be zoomed smoothly. Comparing small movements from one date to another is easy since the pointer on each screen is in exactly the same position.


There's nothing on the internet like this & anyone following glacial movements, fracture development or looking for changes in fast ice will find it invaluable.


Terry

ChrisReynolds

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #117 on: March 31, 2013, 10:16:23 PM »
Terry,

Seconded.

frankendoodle

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #118 on: March 31, 2013, 11:18:31 PM »
I was just looking at the cracks in the Beaufort Sea ice sheet while watching a NASA animation posted on arctic.io when it struck me that the Beaufort Sea was the area that melted first and  the fastest last summer. It also reached temperatures exceeding 15 C  near the Canadian coast. I remember relatively minor cracks NW of the Canadian Archipelago last May, but nothing like this year. 

Apocalypse4Real

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #119 on: April 02, 2013, 04:08:57 AM »
I expect further fragmentation and breakup in to smaller floes in the next week, and more fracturing on the Russian and Canadian Arctic areas. Attached is the CICE movement for April 6 2013 as an illustration.

Even if we go to a positive anomaly, I suggest the motion will continue.

Apocalypse4Real

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #120 on: April 02, 2013, 03:03:38 PM »
Furthermore, fracturing continues to redevelop, and breakup the ice into smaller sections.

When melt season finally arrives both the Beaufort and areas north of Ellesmere will be more mobile and vulnerable.

The AVHRR imagery is from April 2, 2013.

Espen

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #121 on: April 04, 2013, 03:19:17 PM »
A-Team and Sigmetnow:

Today April 4:
Pre-Fractures are now clearly seen into the CAA from the north, between Ellesmere ; Ellef Ringnes and Banks Island.

I am sure we will soon need some animators to cover this story
« Last Edit: April 04, 2013, 06:30:57 PM by Espen »
Have a ice day!

Jim Williams

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #122 on: April 04, 2013, 05:34:59 PM »
It there any actual data on Ice thickness this Spring?  (I'll leave it at that and not speculate on Models which have been doing fairly well.)

deep octopus

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #123 on: April 04, 2013, 05:52:59 PM »
Espen, I was beginning to notice that same thing as well. And the wounds north of Ellesmere have been trying to punch through once again, as of yesterday. In a few more hours, we should see if this has significantly changed.
http://earthdata.nasa.gov/labs/worldview/?map=-1189152.9140625,-189523.3046875,-464160.9140625,198060.6953125&products=baselayers.MODIS_Terra_CorrectedReflectance_TrueColor~overlays.arctic_coastlines&time=2013-04-03T12:00:00&switch=arctic

Also, the ice pack north of Ellesmere/CAA in general is clearly moving in the clockwise/westward direction, comparing April 2nd with April 3rd, now that the clouds have moved away for now. This is looking like a very loose tooth, I fear.
« Last Edit: April 04, 2013, 05:59:10 PM by Deep Octopus »

Espen

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #124 on: April 04, 2013, 06:40:36 PM »
Deep Octopus;

Yes the fraction-action is not over yet!
Have a ice day!

Espen

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #125 on: April 04, 2013, 10:35:45 PM »
The pre-fracs into northern CAA are now seen in the Modis too, when scrutinized:

http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?subset=Arctic_r04c02.2013094.aqua.250m
Have a ice day!

Sigmetnow

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #126 on: April 05, 2013, 02:18:02 AM »
Here’s north and northeast of Banks Island, on April 1 and April 2, 2013.  This is from www.arctic.io > Sea Ice > Split Zooms.  (Thanks, Terry!)  Please ignore the red arrow.

Is the wider appearance of the major cracks on April 2 mostly due to clouds from water vapor coming off open water in the cracks?
People who say it cannot be done should not interrupt those who are doing it.

TerryM

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #127 on: April 05, 2013, 07:47:14 AM »
sigmetnow


Save the thanks for Arcticio, he posts here regularly and has put an unbelievable amount of work into his sight. I much prefer his method of moving around in MODIS & as I mentioned, and you now know, there is no better way of checking for small shifts in Arctic ice than his split zoom.


Come melt season I spend hours there checking fjords, fast ice, melt ponds & any other things that have caught my attention. The split zoom feature is quite new (end of last season) and still has problems from time to time - but when it's up it's totally unreal.


Terry

Sigmetnow

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #128 on: April 05, 2013, 02:48:49 PM »
Well then, Terry:  Thanks for the info and link to arctic.io !  It does indeed have a bunch of good stuff to go through.  There goes another chunk of my spare time!
People who say it cannot be done should not interrupt those who are doing it.

Sigmetnow

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #129 on: April 07, 2013, 02:52:09 PM »
This Huffington Post article has an excellent video animation of the Beaufort Sea Ice Fracturing, plus several beautiful glacier and “Climate Change” photos, and a some interesting Arctic Sea Ice news videos.

http://www.huffingtonpost.ca/2013/04/04/beaufort-sea-ice-fracture-video_n_3015085.html
People who say it cannot be done should not interrupt those who are doing it.

Apocalypse4Real

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #130 on: April 14, 2013, 04:56:26 PM »
We have been engaged in a conversation about whether the fragmentation event will impact summer melt season.

One question has been whether the ice would be more mobile, in other words, if additional motion of fractured ice would lead to additional melt.

Another question has been whether the NP would be ice free this year.

HYCOM/CICE may be providing additional weight to "yes" answers to both questions.

What follows are HYCOM/CICE  calculations from Jan 1, Mar 1, April 1, and April 21.

Note the fracturing events and the subsequent ice motion into the Beaufort and away from 90 N.

SCYetti

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #131 on: April 15, 2013, 12:53:50 AM »
In reading this discussion I've had the thought that the Arctic could possibly be ice free this year because of the fragmentation event since February. This is due to the increased speed of the Arctic Drift and the Beaufort Gyre. A-Team's visualisation of movement in the gyre showed 479 km movement in less than 6 weeks. This shows extraordinary thinness and weakness of the ice that not only makes it more susceptible to melt but also to being flushed into the Atlantic.

In order to contribute more than my opinion; I found this article that discusses ice speed and thickness and how lack of consideration these relate to the inadequacies of Arctic Models.

http://web.mit.edu/~rampal/rampal_homepage/Publications_files/Rampal2011_J.%20Geophys.%20Res.pdf

Apocalypse4Real

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #132 on: April 18, 2013, 03:28:58 AM »
NASA has put up a new Youtube video in regard to Arctic Sea Ice maximum and the fracturing.

While helpful, it does not address all of the issues of this winter's ice behavior.



Donna

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #133 on: April 18, 2013, 04:06:54 AM »
While helpful, it does not address all of the issues of this winter's ice behavior.


 

From the video "...where we might see virtually ice free summers in the arctic in just a few decades." 

I wish I were that optimistic.

ggelsrinc

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #134 on: April 19, 2013, 12:34:20 AM »
Is it possible that a fragmentation event could actually benefit the sea ice and could ice breakers do so early enough in proper weather?

Are there any good studies on sea ice losing it's salinity?

crandles

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #135 on: April 19, 2013, 12:53:45 AM »
Fragmentation is likely causing increased ice ridging elsewhere an increase in ice volume. I doubt we would be likely to have enough ice breakers to have significant effect. It is likely that effect in fall/winter is to increase volume but use in spring and summer decreases albedo and leads to more heat absorption within the pack.

More icebreakers would probably mean more use in spring rather than mainly in fall & winter so probably not beneficial.

Miles travelled would be small compared to all those cracks we have seen.

Was there a link with salinity?

ggelsrinc

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #136 on: April 19, 2013, 01:13:31 AM »
Fragmentation is likely causing increased ice ridging elsewhere an increase in ice volume. I doubt we would be likely to have enough ice breakers to have significant effect. It is likely that effect in fall/winter is to increase volume but use in spring and summer decreases albedo and leads to more heat absorption within the pack.

More icebreakers would probably mean more use in spring rather than mainly in fall & winter so probably not beneficial.

Miles travelled would be small compared to all those cracks we have seen.

Was there a link with salinity?

I figured a fragmentation event would have to be early to strengthen the sea ice, but it could cause the sea ice to resist being melted to ice free conditions and it could be used to make sea ice with ice breakers. I thought the Russians were building them anticipating a new trade route.

The sea ice has to lose it's salinity to strengthen, so I was wondering how fast it can lose salinity. I recall cases where antarctic sea ice was strengthened because too much snow cover caused it to crack and sink and the sea water froze turning snow to ice.

crandles

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #137 on: April 19, 2013, 01:53:44 AM »
I don't imagine fragmentation doing anything but weaken the ice. There is likely somewhere else where ridging is thickening ice. So the extra volume is elsewhere. The new ice forming in cracks is likely formed fast and therefore salty and new.

To lose salinity you really want temperature changes to cause salty parts of the ice to melt and drain then refreeze then melt different salty parts of the ice and keep repeating. Lower latitudes that get bigger differences in sun angle may be more suitable location. Probably lots of references on brine rejection.

Juan C. García

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #138 on: April 19, 2013, 07:06:16 AM »
This area has a crack that has stayed for the whole April. From my point of view is growing, becoming wider than before. I don’t remember seeing something like this in the past. The Arctic sea ice is very weak.



http://www.iup.uni-bremen.de:8084/amsr2/arctic_AMSR2_nic.png
« Last Edit: April 19, 2013, 07:11:53 AM by Juan C. García »
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

wanderer

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #139 on: April 19, 2013, 10:22:13 AM »
It's easy to watch with Worldview:
http://earthdata.nasa.gov/labs/worldview/?map=-2307040,-1098304,2690080,3218880&products=baselayers,MODIS_Terra_CorrectedReflectance_TrueColor~overlays,arctic_coastlines&time=2013-04-19&switch=arctic

Compare it to May 2012 - a similar cracking is visible.
On May 8th (when records started in 2012) we will see how big the difference is.

Jim Hunt

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #140 on: April 19, 2013, 03:42:48 PM »
Juan's crack has been opening/freezing for many weeks, just like those over in the Beaufort, where you can see the "Wrangel end" of it:

http://econnexus.org/beaufort-sea-ice-cracks-once-more/

Also just like those, it's briefly "reopened" recently. Whether any of them "stay open" this early in the year is "the 64 trillion dollar question"!
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Vergent

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #141 on: April 19, 2013, 04:48:48 PM »
It's easy to watch with Worldview:
http://earthdata.nasa.gov/labs/worldview/?map=-2307040,-1098304,2690080,3218880&products=baselayers,MODIS_Terra_CorrectedReflectance_TrueColor~overlays,arctic_coastlines&time=2013-04-19&switch=arctic

Compare it to May 2012 - a similar cracking is visible.
On May 8th (when records started in 2012) we will see how big the difference is.


http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/?mosaic=Arctic.2012109.terra.4km.jpg

Earlier images are available direct from NASA LANCE-MODIS

The 2012109 in the address is the year/julian day. Change it to whatever you want to see.


V

ChrisReynolds

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #142 on: April 19, 2013, 09:09:22 PM »
Juan,

That's a coastal flaw lead. It normally follows the coast but at present moves into the pack around a region of thicker compacted land fast ice that was subjected to compression and ridging during the February/March fracturing event.

PIOMAS shows it as being a thick region of ice.
http://farm9.staticflickr.com/8523/8639697147_140715b595_o.png

It can be seen in the following graphic which shows net ice movement between 19 Feb and 5 March.
http://farm9.staticflickr.com/8248/8534579476_7aa84d8919_o.gif

ASCAT shows that while the net movement is rather more complex than in the fracturing event there is a consistent movement away from the Siberian coast, which in this case is the edge of the landfast ice pack. This is the typical winter state, where the transpolar drift draws ice away from Siberia and towards the CAA and Fram outflow, with new ice forming in the leads created by the Siberian divergence.

The area of this lead may represent the region where the melt starts in June, however despite compression and ridging the Siberian landfast ice won't last much into June.

Juan C. García

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #143 on: April 20, 2013, 08:01:58 AM »
Thanks Wanderer, Jim, Vergent and Cris from your answers.
I think that we will have to wait a couple of weeks to see how the crack will develop, but at this moment, I believe that the fragmentation event will be a topic on April/May and it will have an important impact in this melting season.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Yuha

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #144 on: April 21, 2013, 05:49:30 AM »
ASCAT shows that while the net movement is rather more complex than in the fracturing event there is a consistent movement away from the Siberian coast

There has also been consistent movement of MYI towards Beaufort Sea squeezing FYI against the coast. That MYI and compressed FYI might delay the melt there. At least the very early melt that looked likely after the fracturing event is now less likely.

Of course, the winds may turn and change the situation again.

ChrisReynolds

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #145 on: April 21, 2013, 07:52:30 AM »
Yuha,

The MYI has partly moved into Beaufort, but I still think the extent is less than normal. Then we have the leads which will open up in the fractures that opened in Feb/Mar. I still expect rather an aggressive melt in Beaufort.

Neven

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #146 on: April 21, 2013, 11:47:20 AM »
I still expect rather an aggressive melt in Beaufort.

I'm rather certain of it. I believe last year's cracking event had started around this time, so it's just a matter of the right winds to tear things apart.

I believe I'm already seeing some patches of open water north of Barrow on yesterday's satellite image.

But conditions will remain cloudy for some time to come. Maybe that could slow things down.
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Jim Hunt

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #147 on: April 21, 2013, 02:31:07 PM »
Juan's "coastal flaw lead" grows ever wider:

http://econnexus.org/has-the-laptev-sea-started-melting/

Will that trend continue, do you suppose?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Whit

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #148 on: April 21, 2013, 05:07:15 PM »
Comparing this years ice to last years it seems that this years ice in the cracked up areas are of a different quality. I don't think everything can be attributed to thickness alone.

In several areas in for instance The Beaufort and Chuckchi-seas, the cracks last year were more angular and seemed to "fit better" in the pattern left after the cracking events.

This year the cracked areas have several patterns where the floes seem more rounded and the cracks seem messier.

Based on this I would say the ice in the cracked areas generally is softer and more prone to crumbling than it was on May 8th 2012. It's a general impression I get just by comparing images in eos worldview.

Granular uneven cracks and varying floe-sizes (2013) vs. angular even cracks with more uniform floe-sizes (2012), might be one way of expressing what I'm thinking about.

Has anyone else got the same impression?
« Last Edit: April 21, 2013, 05:23:34 PM by Whit »
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Sigmetnow

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Re: Fragmentation Event. Will it have impact over the summer melt season?
« Reply #149 on: April 22, 2013, 12:33:55 AM »
Back in the Beaufort Sea, there have been lots of clouds over the main ice pack, but the Navy HYCOM ice thickness graphics suggest significant fracturing and movement south is occurring.  Here’s April 1 to April 20 (missing April 16).
People who say it cannot be done should not interrupt those who are doing it.