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solartim27

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Re: Rift in Larsen C
« Reply #50 on: January 20, 2017, 07:25:39 AM »
The linked article, entitled:"Larsen ice crack continues to open up",
http://www.nbc.com/blindspot/video/nor-i-nigel-aka-leg-in-iron/3446618

I think that should be
http://www.bbc.com/news/science-environment-38686626
Quote
"Although you might expect any extension to hasten the point of calving, it actually remains impossible to predict when it will break because the fracture process is so complex.
"My feeling is that this new development suggests something will happen within weeks to months, but there is an outside chance that further growth will be slow for longer than that.
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Seumas

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Re: Rift in Larsen C
« Reply #51 on: January 20, 2017, 10:41:19 AM »
That's actually another update from the Project Midas team:

http://www.projectmidas.org/blog/larsen-c-rift-continues-to-grow/

They send them out as press releases, so you'll see them in several places. But any time you spot that map with Wales as the size comparison, that's them  :D

EDIT: Though, oddly, there's always more detail in the BBC report than on their own blog. I guess the reporter gets more out of them!

iwantatr8

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Re: Rift in Larsen C
« Reply #52 on: January 20, 2017, 02:07:05 PM »
Now this is an interesting tool for monitoring using Sentinel 2 images.

http://apps.sentinel-hub.com/sentinel-playground/#lat=-67.58776309484115/lng=-61.321563720703125/zoom=10/preset=CUSTOM/layers=B05,B03,B01/maxcc=8/gain=0.4/time=2015-01-01|2017-01-13/cloudCorrection=replace/colCor=SenCor/

magnamentis

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Re: Rift in Larsen C
« Reply #53 on: January 20, 2017, 03:04:43 PM »
countdown to break away is running relentlessly, will take perhaps just one nice westerly storm to push that part into oblivion ( warmer waters after breaking away )

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Re: Rift in Larsen C
« Reply #54 on: January 21, 2017, 03:30:16 AM »
That's actually another update from the Project Midas team:

http://www.projectmidas.org/blog/larsen-c-rift-continues-to-grow/

They send them out as press releases, so you'll see them in several places. But any time you spot that map with Wales as the size comparison, that's them  :D

EDIT: Though, oddly, there's always more detail in the BBC report than on their own blog. I guess the reporter gets more out of them!

That rift width chart is perhaps the more concerning one right now. 500m is very large.

DrTskoul

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Re: Rift in Larsen C
« Reply #55 on: January 21, 2017, 04:58:41 AM »
Cracks in anisotropic materials are some wild unpredictable beasts... I think the scales have tipped over for LC...But I would not be surprised if it takes a rest first...

magnamentis

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Re: Rift in Larsen C
« Reply #56 on: January 21, 2017, 01:35:16 PM »
Cracks in anisotropic materials are some wild unpredictable beasts... I think the scales have tipped over for LC...But I would not be surprised if it takes a rest first...

you put that perfectly well, thanks for finding the right words :-)

solartim27

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Re: Rift in Larsen C
« Reply #57 on: January 23, 2017, 11:48:29 PM »
I'm not sure if this is an advance, or just the change in satellite view, but it's only a couple of days difference.

http://www.polarview.aq/images/105_S1jpgfull/S1A_EW_GRDM_1SSH_20170123T001522_3CA4_S_1.final.jpg (28 MB)

S1A_EW_GRDM_1SSH_20170118T000717_9C56_S_1.final.jpg  (30 MB)
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DrTskoul

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Re: Rift in Larsen C
« Reply #58 on: January 24, 2017, 12:01:09 AM »
I'm not sure if this is an advance, or just the change in satellite view, but it's only a couple of days difference.

http://www.polarview.aq/images/105_S1jpgfull/S1A_EW_GRDM_1SSH_20170123T001522_3CA4_S_1.final.jpg (28 MB)

S1A_EW_GRDM_1SSH_20170118T000717_9C56_S_1.final.jpg  (30 MB)

Seems like an advance....

swoozle

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Re: Rift in Larsen C
« Reply #59 on: January 24, 2017, 02:54:55 AM »
I'm not sure if this is an advance, or just the change in satellite view, but it's only a couple of days difference.

http://www.polarview.aq/images/105_S1jpgfull/S1A_EW_GRDM_1SSH_20170123T001522_3CA4_S_1.final.jpg (28 MB)

S1A_EW_GRDM_1SSH_20170118T000717_9C56_S_1.final.jpg  (30 MB)

But it looks like the earlier image (20170118) has the longer crack. Must be a trick of the lighting.
« Last Edit: January 24, 2017, 03:02:29 AM by swoozle »

LRC1962

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Re: Rift in Larsen C
« Reply #60 on: January 29, 2017, 12:28:49 AM »
http://www.npr.org/sections/thetwo-way/2017/01/16/509565462/an-ice-shelf-is-cracking-in-antarctica-but-not-for-the-reason-you-think
Quote
One puzzling aspect is how it managed to plow through areas of softer ice, called suture zones, that bind the ice from neighboring glaciers into one giant sheet.

"There's something different about that ice that slows it down or causes it to hang up for some period of time," says Dan McGrath, a glaciologist at Colorado State University. But, starting in 2014, that soft ice did very little to slow down this rift.

"We need to get to the bottom of understanding what changed that allowed this rift to progress as it has, and will other rifts follow suit," says McGrath, who spent four field seasons camped out on the Larsen C ice shelf.
"All truth passes through three stages: First, it is ridiculed; Second,  it is violently opposed; and Third, it is accepted as self-evident."
       - Arthur Schopenhauer

magnamentis

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Re: Rift in Larsen C
« Reply #61 on: January 29, 2017, 09:21:53 PM »
http://www.npr.org/sections/thetwo-way/2017/01/16/509565462/an-ice-shelf-is-cracking-in-antarctica-but-not-for-the-reason-you-think
Quote
One puzzling aspect is how it managed to plow through areas of softer ice, called suture zones, that bind the ice from neighboring glaciers into one giant sheet.

"There's something different about that ice that slows it down or causes it to hang up for some period of time," says Dan McGrath, a glaciologist at Colorado State University. But, starting in 2014, that soft ice did very little to slow down this rift.

"We need to get to the bottom of understanding what changed that allowed this rift to progress as it has, and will other rifts follow suit," says McGrath, who spent four field seasons camped out on the Larsen C ice shelf.

best explanation that comes to my mind immediately is the stone that damages a car's front window and one thinks he can live with that small crack, only to find out that the crack will spread with each movement of the car (torsion) after all this is what happens, there is swell action, there is currents action and there is glaciers pushing out to sea action, sufficient sources for movement that will widen each crack until a part of the structures will detach one or the other way.

BTW i still think that, considering topography and prevailing winds, that there must be some kind of "Foehn" winds
heading down from the highs of the peninsula and sooner or later pusch that entire ice sheet out into the southern atlantic or beyond.

DavidR

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Re: Rift in Larsen C
« Reply #62 on: February 01, 2017, 02:28:27 AM »
http://www.npr.org/sections/thetwo-way/2017/01/16/509565462/an-ice-shelf-is-cracking-in-antarctica-but-not-for-the-reason-you-think
Quote
One puzzling aspect is how it managed to plow through areas of softer ice, called suture zones, that bind the ice from neighboring glaciers into one giant sheet.

"There's something different about that ice that slows it down or causes it to hang up for some period of time," says Dan McGrath, a glaciologist at Colorado State University. But, starting in 2014, that soft ice did very little to slow down this rift.

"We need to get to the bottom of understanding what changed that allowed this rift to progress as it has, and will other rifts follow suit," says McGrath, who spent four field seasons camped out on the Larsen C ice shelf.

best explanation that comes to my mind immediately is the stone that damages a car's front window and one thinks he can live with that small crack, only to find out that the crack will spread with each movement of the car (torsion) after all this is what happens, there is swell action, there is currents action and there is glaciers pushing out to sea action, sufficient sources for movement that will widen each crack until a part of the structures will detach one or the other way.

I  would have thought the most obvious solution is the weight of unsupported ice. The ice is melting from the bottom and presumably most at the edges.   As this occurs the ice has to drop or the ratio of the ice above sea level to  below sea level will increase. Somewhere this is going to  cause a crack across the ice and  the creation of the crack will cause extra pressure at the ends of the crack causing the cracking to accelerate.  This rate of cracking would be greater that that caused by swell and currents.  If the crack occurs at a point that  has been thinned by under-ice currents it is easy to imagine that after the first section breaks off the next section is also vulnerable.

The soft ice might prevent the propagation of the crack if it was due to normal tides and currents but would not halt a crack caused by the weight of the ice seaward of the crack.   

Just a novices opinion!
Toto, I've a feeling we're not in Kansas anymore

oren

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Re: Rift in Larsen C
« Reply #63 on: February 01, 2017, 06:55:28 AM »
Just a novices opinion!
Excellent point DavidR (novice to novice...). Basal melt seaward of the crack is a very good explanation. I wonder if there are any papers on this issue.

magnamentis

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Re: Rift in Larsen C
« Reply #64 on: February 01, 2017, 10:10:33 AM »
Just a novices opinion!

a very logical and hence valid point IMO, most probably as usual it's a combo of factors while i would second your opinion to have the greater impact than the factors i mentionend. i'd put this on top of the list.

thanks for that input :-)

Seumas

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Re: Rift in Larsen C
« Reply #65 on: February 07, 2017, 02:01:07 PM »
The MIDAS folk have posted another update: a FAQ on the rift:

http://www.projectmidas.org/blog/rift-faq/

Susan Anderson

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Re: Rift in Larsen C
« Reply #66 on: February 07, 2017, 04:10:54 PM »
The New York Times webpage has an article on the rift, with excellent graphics, front and center today.
https://www.nytimes.com/interactive/2017/02/07/science/earth/antarctic-crack.html

(Everyone can access 10 free per month; their graphics won't copy.)

Tor Bejnar

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Re: Rift in Larsen C
« Reply #67 on: February 07, 2017, 04:49:20 PM »
There are always screenshots!
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Tor Bejnar

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Re: Rift in Larsen C
« Reply #68 on: February 07, 2017, 08:21:02 PM »
I sometimes wonder if what I'm seeing is what others are seeing.  To that end, I've made a screenshot of a PolarView image and put pairs of arrows showing where I see the rift.  The second image is to put it into the wider perspective: the one pair of arrows shows the area where I see the rift ending.  Because these are screenshots, looking at the 'original' may be more informative. (click images to enlarge)
« Last Edit: February 07, 2017, 08:35:05 PM by Tor Bejnar »
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

solartim27

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Re: Rift in Larsen C
« Reply #69 on: February 07, 2017, 08:32:03 PM »
I think the rift goes just to the left of your arrows.  Time will tell.
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Re: Rift in Larsen C
« Reply #70 on: February 09, 2017, 02:31:24 PM »
First cloud free S2A image is in. I marked the end of the rift with GCP1 (Ground Control Point)

Link to Sentinel Playground
http://apps.sentinel-hub.com/sentinel-playground/#lat=-67.38663858288848/lng=-61.14372253417969/zoom=11/preset=1_NATURAL_COLOR/layers=B04,B03,B02/maxcc=22/gain=0.3/time=2015-01-01|2017-02-09/cloudCorrection=none/colCor=/evalscript=
« Last Edit: February 09, 2017, 04:47:44 PM by Tealight »

Tor Bejnar

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Re: Rift in Larsen C
« Reply #71 on: February 09, 2017, 04:30:20 PM »
First cloud free S2A image is in. I marked the end of the rift with GCP1 (Ground Control Point)
Link to Sentinel Playground
http://apps.sentinel-hub.com/sentinel-playground/#lat=-67.38663858288848/lng=-61.14372253417969/zoom=11/preset=1_NATURAL_COLOR/layers=B04,B03,B02/maxcc=22/gain=0.3/time=2015-01-01|2017-02-09/cloudCorrection=none/colCor=/evalscript=
Using this "Sentinel Playground" image, I see the rift going to the circle in the general location image and the enlargement that has two pairs of arrows pointing to the rift.  (The lineation - rift - extends slightly above the top pair.)  Tealight and I show different orientations, but the end point may be 'the same'.
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

georged

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Re: Rift in Larsen C
« Reply #72 on: February 10, 2017, 05:32:31 AM »
First cloud free S2A image is in. I marked the end of the rift with GCP1 (Ground Control Point)
Link to Sentinel Playground
http://apps.sentinel-hub.com/sentinel-playground/#lat=-67.38663858288848/lng=-61.14372253417969/zoom=11/preset=1_NATURAL_COLOR/layers=B04,B03,B02/maxcc=22/gain=0.3/time=2015-01-01|2017-02-09/cloudCorrection=none/colCor=/evalscript=
Using this "Sentinel Playground" image, I see the rift going to the circle in the general location image and the enlargement that has two pairs of arrows pointing to the rift.  (The lineation - rift - extends slightly above the top pair.)  Tealight and I show different orientations, but the end point may be 'the same'.

Interestingly, at the end the rift appears to 'split' into several separate rifts. I'm not sure whether this is simply an artifact or real.

The rift is currently about 25km from the shelf edge. How would we describe the series of rift-like features approximately 100km north and south of the rift end?

Tony Mcleod

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Re: Rift in Larsen C
« Reply #73 on: February 10, 2017, 07:50:07 AM »
It would be amazing to be near the end of it and to hear it groaning and crackling. :o

BornFromTheVoid

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Re: Rift in Larsen C
« Reply #74 on: February 16, 2017, 02:30:58 PM »
Hey folks, were hosting a Q&A session on reddit.com/r/science today that might be of interest to some here

American Geophysical Union AMA: Hi Reddit, I’m Chris Borstad, and I’m here to talk about the peculiar nature of snow and ice related to avalanches and glaciers. Ask Me Anything!

Hi Reddit! I am Chris Borstad, Associate Professor of Snow and Ice Physics at the University Centre in Svalbard (UNIS). Located at 78 degrees north, UNIS (www.unis.no) is the northernmost institution of higher education and research in the world. I am fascinated by snow and ice, and my research relates to processes that cause ice and snow to fracture. Most recently I have been studying the Larsen C ice shelf in Antarctica, where a massive crack in the ice is about to release an iceberg the size of Delaware! By improving our understanding of what caused this event and what the consequences are for the ice shelf, we hope to make better predictions of how other ice shelves around Antarctica will respond to a changing climate. I also study the physics of snow avalanches, a research interest that originated with a desire not to get caught in an avalanche myself while skiing in the backcountry. The most destructive types of avalanches occur after a large volume of snow is undercut by fractures. I am working to better understand these fascinating natural phenomena so that we can hopefully keep people out of harm’s way.
I will be back to answer your questions at 12 pm ET, Ask me Anything!
Follow me on twitter @RogueChrisB.


https://www.reddit.com/r/science/comments/5uer59/american_geophysical_union_ama_hi_reddit_im_chris/
I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Espen

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Re: Rift in Larsen C
« Reply #75 on: February 18, 2017, 07:01:41 PM »
Larsen C rift expanding further:

Please click to enlarge and animate!
Have a ice day!

DrTskoul

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Re: Rift in Larsen C
« Reply #76 on: February 18, 2017, 08:43:59 PM »
Almost there....

Tor Bejnar

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Re: Rift in Larsen C
« Reply #77 on: February 18, 2017, 11:30:13 PM »
I find it curious that the crack keeps going "up" (the image) and not "out" (to the coast).  Does anybody have ideas, or knowledge, about the stresses on or weaknesses in the ice shelf that would cause the crack to continue to propagate quasi-parallel to the coast?
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DrTskoul

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Re: Rift in Larsen C
« Reply #78 on: February 19, 2017, 12:39:47 AM »
My experience with cracks in glassy materials is that they do not kink but smoothly change direction. So the crack would curve but not take a right turn unless there is a significant defrct. For the shelf a big hill ?
« Last Edit: February 19, 2017, 01:01:53 AM by DrTskoul »

magnamentis

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Re: Rift in Larsen C
« Reply #79 on: February 19, 2017, 12:43:15 AM »
I find it curious that the crack keeps going "up" (the image) and not "out" (to the coast).  Does anybody have ideas, or knowledge, about the stresses on or weaknesses in the ice shelf that would cause the crack to continue to propagate quasi-parallel to the coast?

has to do with the structure from where the ice originates. glaciers for example use to crack more or less 90 degrees to their flowing direction and i could imagine that this ice is built on or close to land and drifting out, similar like a glacier's ice flows down the valley. there are many experts on glaciology in this forum who can certainly explain it better and/or rectify what's wrong with my assumption.

DrTskoul

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Re: Rift in Larsen C
« Reply #80 on: February 19, 2017, 01:02:58 AM »
Also the stress profile depends on the anchor points of the shelf.

iwantatr8

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Re: Rift in Larsen C
« Reply #81 on: February 19, 2017, 09:53:53 AM »
Nature has an article on the shelf stresses here:

http://www.nature.com/articles/ncomms4707

which contains the helpful image below, looks like a curve to the east can be expected soon.

Mozi

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Re: Rift in Larsen C
« Reply #82 on: February 22, 2017, 06:59:29 PM »
The British Antarctic Service has posted an article with an attached video of the rift - quite striking footage.

http://www.climatecentral.org/news/scientists-larsen-c-crack-21178

"On Tuesday, researchers with the British Antarctic Survey released new aerial footage showing the widening rift that threatens to tear the ice shelf asunder at any moment. The footage makes the immensity of the crack clear, as the yawning chasm stretches off into the horizon."


Bill Fothergill

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Re: Rift in Larsen C
« Reply #83 on: February 23, 2017, 10:48:08 AM »
Here are some new links on the topic (although there is a fair bit of repetition between them)...

https://www.bas.ac.uk/media-post/new-footage-shows-rift-in-larsen-c-ice-shelf/

http://www.bbc.co.uk/news/science-environment-39055524


Regarding the earlier discussions about the crack mechanism(s) and the almost orthogonal relationship between the flow direction and the major stress axis ...

It's been a bloody long time since I've even thought about mechanics (it was covered in second year at University, and then more or less flushed out from what passes for a brain during that summer's vacation) but the bending/cracking idea makes perfect sense to me. (Although that doesn't mean very much!)

The bathymetry around Antarctica has lots of places where, as one moves towards the continent from the off-shore grounding line, the depth actually increases for a while.  That means that glaciers/ ice shelves are prone to serious undercutting. That would put the top surface of the ice into tension, whilst the bottom surface is in compression. This is a classic way to produce a fracture, and, like so many other aspects of climate change, it has a nasty feedback mechanism. As the crack propagates, it leaves less of the ice unfractured, with increasingly more of the bending moment being resisted by an ever-decreasing amount of ice.

Tor Bejnar

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Re: Rift in Larsen C
« Reply #84 on: March 06, 2017, 08:11:05 PM »
I've vaguely outlined in orange the end of the rift in the shelf and outlined in black a lineation that crosses the rift and goes to the coast.

Sentinel screenshot from PolarView Acquired: 05-03-2017 19:14:40

Is the "in black" lineation a weakness of some sort?
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DrTskoul

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Re: Rift in Larsen C
« Reply #85 on: March 06, 2017, 08:19:56 PM »
I've vaguely outlined in orange the end of the rift in the shelf and outlined in black a lineation that crosses the rift and goes to the coast.

Sentinel screenshot from PolarView Acquired: 05-03-2017 19:14:40

Is the "in black" lineation a weakness of some sort?

Something big is coming....

bairgon

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Re: Rift in Larsen C
« Reply #86 on: March 06, 2017, 09:22:18 PM »
I noticed what looks like a warm foehn wind forecast for the 10th, blowing off the ice shelf. Maybe that will help things along?

https://earth.nullschool.net/#2017/03/10/1800Z/wind/surface/level/overlay=temp/orthographic=2.76,-66.17,1203/loc=-61.901,-67.389

iwantatr8

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Re: Rift in Larsen C
« Reply #87 on: March 07, 2017, 11:44:48 AM »
Tor,

If you look at the Sentinel 2 image from 15th Feb

http://apps.sentinel-hub.com/sentinel-playground/#lat=-67.70110969585656/lng=-61.219940185546875/zoom=10/preset=CUSTOM/layers=B05,B03,B02/maxcc=100/gain=0.3/gamma=1/time=2015-01-01|2017-02-15/cloudCorrection=replace/atmFilter=/evalscript=/showImage

It clearly shows that the end crack is much further north than the area where you have shown, the cloud cover in the last few weeks makes it difficult to track but it will be quite interesting to see if the summer has enough energy left to create the calving or if we will be waiting for next year.


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Re: Rift in Larsen C
« Reply #88 on: March 07, 2017, 06:29:44 PM »
Apologies if this has been asked before....but is the Larsen C INCLUDED in the "sea ice" numbers....or are the ice shelve's NOT included in the sea ice numbers?

I guess to state another way....there seems to be 3 "types" of ice talked about:  Land ice, ice shelves, and sea ice.  For purposes of the various organizations that measure the "sea ice".....are the ice shelves included or excluded from their calculations?



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DrTskoul

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Re: Rift in Larsen C
« Reply #89 on: March 07, 2017, 07:17:06 PM »
Apologies if this has been asked before....but is the Larsen C INCLUDED in the "sea ice" numbers....or are the ice shelve's NOT included in the sea ice numbers?

I guess to state another way....there seems to be 3 "types" of ice talked about:  Land ice, ice shelves, and sea ice.  For purposes of the various organizations that measure the "sea ice".....are the ice shelves included or excluded from their calculations?

Excluded

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Re: Rift in Larsen C
« Reply #90 on: March 07, 2017, 07:31:44 PM »
Quote
Excluded

Thanks...

So what that means.....if someone is just looking at the "sea ice numbers" to study "albedo" for instance......those numbers are UNDERSTATING the downturn in the albedo effect from sea ice.....because any shelf ice "lost to melting" doesn't impact the sea ice numbers.

Now....I don't FOR A MINUTE believe that the scientists don't know that (I'm sure they do)....and hopefully work THAT into THEIR calculations.....but for a science novice such as me, it is one more piece of the puzzle that "goes the wrong way".

Because not only are we continuing to have less reflective sea ice.....we're losing ice shelves as well.  Just more "bad news" to plug in......unless ice shelves are GROWING somewhere else in the Antarctic.





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solartim27

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Re: Rift in Larsen C
« Reply #91 on: March 07, 2017, 07:47:01 PM »
Well, they get included when they break off, so sea ice will have a big jump soon (I think a year at least).
FNORD

FredBear

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Re: Rift in Larsen C
« Reply #92 on: March 07, 2017, 08:26:00 PM »
But the ice shelf masks stay the same? So the floating iceberg counts as sea ice but the sea ice replacing it counts as ice shelf!

charles_oil

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Re: Rift in Larsen C
« Reply #93 on: March 08, 2017, 12:32:19 AM »

In the sea Ice around Antarctica thread the area is currently (record minimum) around 1,500,000 km2 so 5,000km2 - the size of the potential loss of the shelf is quite small in area % terms - probably lost within normally daily increase / decrease figures though it obviously represents a massive volume compared to thin, surface ice. 
See: Re: Sea Ice Extent around Antarctica                           
« Reply #561 on: March 07, 2017, 01:59:45 PM »


I can't seem to find any measures of arctic sea ice volume so dont know what fraction it would represent (or if it would skew the figures)

prokaryotes

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Re: Rift in Larsen C
« Reply #94 on: April 14, 2017, 05:05:41 PM »
The Making of an Iceberg
April 14, 2017

Quote
In 2014, a crack began opening in the Larsen C Ice Shelf—a huge slab of floating ice along the Antarctic Peninsula. By April 2017, only 16 kilometers (10 miles) of ice separated the tip of that crack from the open sea.
Predicting when the cracking shelf will set loose an iceberg is a challenge because ice fracturing depends on several factors, some of which are poorly understood. The iceberg, which is likely to be the size of Rhode Island, could break off any time from days to years from now, according to scientists from Project MIDAS, a United Kingdom-based group that is monitoring the event.
https://earthobservatory.nasa.gov/IOTD/view.php?id=90021

oren

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Re: Rift in Larsen C
« Reply #95 on: April 14, 2017, 07:42:48 PM »
The Making of an Iceberg
April 14, 2017
Quote
In 2014, a crack began opening in the Larsen C Ice Shelf—a huge slab of floating ice along the Antarctic Peninsula. By April 2017, only 16 kilometers (10 miles) of ice separated the tip of that crack from the open sea.
Predicting when the cracking shelf will set loose an iceberg is a challenge because ice fracturing depends on several factors, some of which are poorly understood. The iceberg, which is likely to be the size of Rhode Island, could break off any time from days to years from now, according to scientists from Project MIDAS, a United Kingdom-based group that is monitoring the event.

I am surprised it's still attached...

prokaryotes

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Re: Rift in Larsen C
« Reply #96 on: April 20, 2017, 08:11:19 PM »
ESA video on Larsen C crack, includes insides into detection with Interferogram (using two radar images)

#interferometry

crandles

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Re: Rift in Larsen C
« Reply #97 on: April 30, 2017, 05:22:15 PM »
Some discussion at

http://www.bbc.co.uk/news/science-environment-39759329

though mainly about foen winds being more prevalent that realised.

Bill Fothergill

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Re: Rift in Larsen C
« Reply #98 on: May 01, 2017, 11:28:08 AM »
I noticed what looks like a warm foehn wind forecast for the 10th, blowing off the ice shelf. Maybe that will help things along?


Depends on how you are using the word "help".  ;)

See this BBC article (or possibly "antarcticle"?) on the Larsen C and the impact of the Foehn effect thereupon...
http://www.bbc.co.uk/news/science-environment-39759329

The BBC probably used this BAS press release as their source...
https://www.bas.ac.uk/media-post/new-insight-into-what-weakens-antarctic-ice-shelves/

Other BAS articles on the Foehn effect can be found...
https://www.bas.ac.uk/?s=Fohn

1rover1

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Re: Rift in Larsen C
« Reply #99 on: May 02, 2017, 05:20:17 PM »

https://www.eurekalert.org/pub_releases/2017-05/su-air050217.php

https://scienceblog.com/493824/larsen-c-antarctic-ice-rift-spreads/

The linked articles note the rift in the Larsen C ice shelf in Antarctica now has a second branch, which is moving in the direction of the ice front.  "While the previous rift tip has not advanced, a new branch of the rift has been initiated. This is approximately 10km behind the previous tip, heading towards the ice-front.  "This is the first significant change to the rift since February of this year. Although the rift length has been static for several months, it has been steadily widening, at rates in excess of a metre per day."