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Collapse! Surprise! -- NASA Earth Obsveratory
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MrPosti...@kymhorsell.com
Mar 29, 2022, 8:49:07 PM3/29/22
to
So stable. So berry stabil. Bang!
<https://earthobservatory.nasa.gov/images/149640/ice-shelf-collapse-in-east-antarctica/>
Ice Shelf Collapse in East Antarctica
The shelfs disintegration in March 2022 has reshaped a landscape where
coastal glacial ice was once thought to be stable.
Kathryn Hansen
20 March 2022
NASA Earth Observatory
Jan 9, 2022
<https://eoimages.gsfc.nasa.gov/images/imagerecords/149000/149640/iceshelfcollapse_oli_202209_lrg.jpg>
NASA Earth Observatory images by Lauren Dauphin, using Landsat data
from the US Geological Survey and MODIS data from NASA EOSDIS
LANCE and GIBS/Worldview.
March 23, 2022
<https://eoimages.gsfc.nasa.gov/images/imagerecords/149000/149640/iceshelfcollapse_oli_202282_lrg.jpg>
It is relatively common for ice shelves in Antarctica to spawn
icebergs. It is less common for an ice shelf to completely
disintegrate. In March 2022, an ice shelf in East Antarctica did
both. The collapse has reshaped a part of the Antarctic landscape
where coastal glacial ice was once thought to be stable.
The change happened fast. At the start of March 2022, the floating
shelf fed by the Glenzer and Conger glaciers was still intact. By the
middle of the month, it had fallen apart. This image pair (above),
acquired by the Operational Land Imager (OLI) on Landsat 8,
shows the shelf before and after it disintegrated.
"The whole shelf collapsed in just around 2 weeks," said Christopher
Shuman, a University of Maryland, Baltimore County, glaciologist based
at NASA's Goddard Space Flight Center. The icy remnants of both
glacial shelf ice and adjacent sea ice dispersed from the waters
around Bowman Island within weeks. "All of this took less than a
month," Shuman said. "It was quite the blowout."
Feb 22 - March 21, 2022
<https://eoimages.gsfc.nasa.gov/images/imagerecords/149000/149640/iceshelfcollapse_tmo_amo_202280_lrg.jpg>
The progression of the collapse is visible in the image series
above. Images were acquired with the Moderate Resolution Imaging
Spectroradiometer (MODIS) on NASA's Terra and Aqua satellites.
The first image shows the ice shelf floating on the Mawson Sea on
Feb 22, 2022, prior to the collapse. Fast ice--a type of sea ice
that becomes "fastened" to the edges of ice shelves, coastlines, and
icebergs--is also part of the mix. For 2 years prior to this image,
the shelf was already in a state of decline. According to Catherine
Walker of the Woods Hole Oceanographic Institution, the shelf was
losing ice at an average rate of about 1 square kilometer per day
through the natural process of iceberg calving.
But in early March 2022, the shelf in front of the Glenzer Glacier
calved a substantial iceberg. Named C-37, the berg initially measured
about 144 square kilometers (56 square miles). A few pieces broke off,
such that C-37 measured about 81 square kilometers on March 12 when
MODIS acquired the second image in the series. The substantial loss of
ice meant the shelf disconnected from Bowman Island. (Note that some
sea ice remained attached to the island.)
"Without being supported by a land anchor, the ice shelf was
destabilized and primed to collapse," said Jonathan Wille, a
postdoctoral researcher at the Université Grenoble Alpes.
According to Wille, an atmospheric river on March 15 appears to have
triggered the shelf's final collapse. The weather system--which caused
temperatures in eastern Antarctica to soar 40 degrees Celsius above
normal--also enhanced ocean swells and amplified winds near the
vulnerable shelf. This likely caused the ice in front of Conger
Glacier to break apart and quickly disperse.
The third MODIS image above shows the area on March 16 after the final
collapse. The event spawned Iceberg C-38, which at the time measured
about 415 square kilometers (160 square miles). The final image in the
series shows the crumbled shelf ice and fast ice as it dispersed in
the sea on March 21.
The loss of an ice shelf is problematic because it can indirectly
contribute to sea level rise. "Ice shelves are essentially the `safety
band' holding up the rest of the Antarctic Ice Sheet," Walker
said. When they collapse, the ice behind them can more quickly flow
into the ocean. "And that is what raises sea levels."
By Antarctic standards, the ice shelf and glaciers that it held back
are relatively small, so the impacts from the collapse are expected to
be minimal. Scientists are more concerned about the location of the
collapse.
"All of the previous collapses have taken place in West Antarctica,
not East Antarctica, which until recently has been thought of as
relatively stable," Walker said. "This is something like a dress
rehearsal for what we could expect from other, more massive ice
shelves if they continue to melt and destabilize. Then we'll really be
past the turnaround point in terms of slowing sea level rise."
Instruments:
Aqua -- MODIS
Landsat 8 -- OLI
Terra -- MODIS
References & Resources
* Twitter (2022, March 24) Catherine Colello Walker.
Accessed March 28, 2022.
<https://twitter.com/CapComCatWalk/status/1507137389432434739?s=20&t=sVyRpZ2zBGzjZHJS6y9aTg>
* US National Ice Center (2022, March 17) Iceberg C-38 Has
Calved as the Conger Ice Shelf Broke Free in the Wilkes Land Region.
Accessed March 28, 2022.
<https://usicecenter.gov/PressRelease/IcebergC38>
* US National Ice Center (2022, March 8) Iceberg C-37 Broke Free
from Bowman Island in the Wilkes Land Region. Accessed March 28, 2022.
<https://usicecenter.gov/PressRelease/IcebergC37>
--
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<https://earthobservatory.nasa.gov/images/149640/ice-shelf-collapse-in-east-antarctica/>
Ice Shelf Collapse in East Antarctica
The shelfs disintegration in March 2022 has reshaped a landscape where
coastal glacial ice was once thought to be stable.
Kathryn Hansen
20 March 2022
NASA Earth Observatory
Jan 9, 2022
<https://eoimages.gsfc.nasa.gov/images/imagerecords/149000/149640/iceshelfcollapse_oli_202209_lrg.jpg>
NASA Earth Observatory images by Lauren Dauphin, using Landsat data
from the US Geological Survey and MODIS data from NASA EOSDIS
LANCE and GIBS/Worldview.
March 23, 2022
<https://eoimages.gsfc.nasa.gov/images/imagerecords/149000/149640/iceshelfcollapse_oli_202282_lrg.jpg>
It is relatively common for ice shelves in Antarctica to spawn
icebergs. It is less common for an ice shelf to completely
disintegrate. In March 2022, an ice shelf in East Antarctica did
both. The collapse has reshaped a part of the Antarctic landscape
where coastal glacial ice was once thought to be stable.
The change happened fast. At the start of March 2022, the floating
shelf fed by the Glenzer and Conger glaciers was still intact. By the
middle of the month, it had fallen apart. This image pair (above),
acquired by the Operational Land Imager (OLI) on Landsat 8,
shows the shelf before and after it disintegrated.
"The whole shelf collapsed in just around 2 weeks," said Christopher
Shuman, a University of Maryland, Baltimore County, glaciologist based
at NASA's Goddard Space Flight Center. The icy remnants of both
glacial shelf ice and adjacent sea ice dispersed from the waters
around Bowman Island within weeks. "All of this took less than a
month," Shuman said. "It was quite the blowout."
Feb 22 - March 21, 2022
<https://eoimages.gsfc.nasa.gov/images/imagerecords/149000/149640/iceshelfcollapse_tmo_amo_202280_lrg.jpg>
The progression of the collapse is visible in the image series
above. Images were acquired with the Moderate Resolution Imaging
Spectroradiometer (MODIS) on NASA's Terra and Aqua satellites.
The first image shows the ice shelf floating on the Mawson Sea on
Feb 22, 2022, prior to the collapse. Fast ice--a type of sea ice
that becomes "fastened" to the edges of ice shelves, coastlines, and
icebergs--is also part of the mix. For 2 years prior to this image,
the shelf was already in a state of decline. According to Catherine
Walker of the Woods Hole Oceanographic Institution, the shelf was
losing ice at an average rate of about 1 square kilometer per day
through the natural process of iceberg calving.
But in early March 2022, the shelf in front of the Glenzer Glacier
calved a substantial iceberg. Named C-37, the berg initially measured
about 144 square kilometers (56 square miles). A few pieces broke off,
such that C-37 measured about 81 square kilometers on March 12 when
MODIS acquired the second image in the series. The substantial loss of
ice meant the shelf disconnected from Bowman Island. (Note that some
sea ice remained attached to the island.)
"Without being supported by a land anchor, the ice shelf was
destabilized and primed to collapse," said Jonathan Wille, a
postdoctoral researcher at the Université Grenoble Alpes.
According to Wille, an atmospheric river on March 15 appears to have
triggered the shelf's final collapse. The weather system--which caused
temperatures in eastern Antarctica to soar 40 degrees Celsius above
normal--also enhanced ocean swells and amplified winds near the
vulnerable shelf. This likely caused the ice in front of Conger
Glacier to break apart and quickly disperse.
The third MODIS image above shows the area on March 16 after the final
collapse. The event spawned Iceberg C-38, which at the time measured
about 415 square kilometers (160 square miles). The final image in the
series shows the crumbled shelf ice and fast ice as it dispersed in
the sea on March 21.
The loss of an ice shelf is problematic because it can indirectly
contribute to sea level rise. "Ice shelves are essentially the `safety
band' holding up the rest of the Antarctic Ice Sheet," Walker
said. When they collapse, the ice behind them can more quickly flow
into the ocean. "And that is what raises sea levels."
By Antarctic standards, the ice shelf and glaciers that it held back
are relatively small, so the impacts from the collapse are expected to
be minimal. Scientists are more concerned about the location of the
collapse.
"All of the previous collapses have taken place in West Antarctica,
not East Antarctica, which until recently has been thought of as
relatively stable," Walker said. "This is something like a dress
rehearsal for what we could expect from other, more massive ice
shelves if they continue to melt and destabilize. Then we'll really be
past the turnaround point in terms of slowing sea level rise."
Instruments:
Aqua -- MODIS
Landsat 8 -- OLI
Terra -- MODIS
References & Resources
* Twitter (2022, March 24) Catherine Colello Walker.
Accessed March 28, 2022.
<https://twitter.com/CapComCatWalk/status/1507137389432434739?s=20&t=sVyRpZ2zBGzjZHJS6y9aTg>
* US National Ice Center (2022, March 17) Iceberg C-38 Has
Calved as the Conger Ice Shelf Broke Free in the Wilkes Land Region.
Accessed March 28, 2022.
<https://usicecenter.gov/PressRelease/IcebergC38>
* US National Ice Center (2022, March 8) Iceberg C-37 Broke Free
from Bowman Island in the Wilkes Land Region. Accessed March 28, 2022.
<https://usicecenter.gov/PressRelease/IcebergC37>
--
Upcoming events:
8 Apr, 11am EDT: NOAA's Billion Dollar Disasters Q1 release
Zelenskyy says Russia's offers to 'radically' reduce assaults are positive,
but 'do not drown out the explosions'
ABC News, 29 Mar 2022 21:13Z
Ukraine President Volodymyr Zelenskyy expresses caution about peace talks in
which Russia offers to "reduce military activity in the Kyiv and Chernihiv
directions".
[Phoney:]
Morrison dismisses veteran Liberal senator's scathing character assessment
ABC News, 29 Mar 2022 21:39Z
The Prime Minister dismisses Concetta Fierravanti-Wells's claim he is a
bully with no moral compass, saying the senator is simply "disappointed" her
time in federal parliament might be coming to an end.
Outgoing Liberal senator calls Scott Morrison an 'autocrat and a bully'
ABC News, 29 Mar 2022 13:52Z
Outgoing Liberal senator Concetta Fierravanti-Wells takes aim at
Prime Minister Scott Morrison, describing him as "a bully with no
moral compass" who pretends to be a man of faith.
[After a "long time" in the parliament Fierravanti-Wells was bumped
down to 3rd place in the pre-selection list for the Senate,
effectively ending her political career].
[Tight!]
There are now a record 5 mn more job openings than unemployed people
in the US
CNBC, 29 Mar 2022 19:57Z
[Get! Out!]
Ukraine war: Dozens of Russian diplomats expelled by 4 EU nations
BBC.com, 29 Mar 2022 17:57Z
[Don't Cut The Grass!]
In Wisconsin: Stowing Mowers, Pleasing Bees
The New York Times, 29 Mar 2022 17:57Z
How Scandals Drove Hillsong to Lose its American Churches
The New York Times, 29 Mar 2022 20:58Z
[Sooo Cooold!]
Wild weather: Severe storms, tornadoes target mns across the US.
Here's the timeline.
USA TODAY, 29 Mar 2022 19:52Z
BREAKING (30 Mar): After "hours and hours of torrential rain" Lismore
in N NSW is again facing flooding as waters rise to within 10-20 cms
of the top of the levees. Some residents told reports they spent the
worst night of their lives listening to the rain and thunder and the
sound of pumps trying to stop the rain flooding under their homes.
One local rain gauge reads more than 600mm over the past 48 hrs.
River levels are expected to rise over 10.6m above normal and flood
the centre of the city later today. Down in the central coast region
of NSW rains have been less furious but video on TV shows raging
rivers flowing across coastal roads. Watch out for the drop on the right!
[Manjana!]
The $6 bn spend on flood relief in federal budget doesn't help with
immediate housing needs for displaced families
ABC News, 29 Mar 2022 20:14Z
Last night's federal budget revealed $6 bn will be spent on flood
relief for communities in south-east Queensland and northern New South Wales,
but those affected say they need immediate housing help.
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to leave her husband in Kyiv
ABC News, 29 Mar 2022 20:13Z
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Ukraine's first lady Olena Zelenska is using the power of her platform to
support those fleeing for their lives.
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The Guardian, 28 Mar 2022 21:02Z
[Don't worry. They all look like rats].
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The Guardian, 29 Mar 2022 16:01Z
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Yahoo Finance, 29 Mar 2022 12:59Z
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The Associated Press, 29 Mar 2022 19:19Z
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calls for security guarantee in latest talks
CNB, 29 Mar 2022 19:30Z
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could take a decade to flow
ABC News, 29 Mar 2022 13:53Z
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promised for the Northern Territory in the federal budget, but it could take
many years before much of the money hits the ground.
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students
ABC News, 29 Mar 2022 17:51Z
China's govt made "solemn representations" to the Australian
govt over what it says was a recent case of a Chinese student arriving
in Sydney only to be interrogated, searched and ultimately have their visa
cancelled.
Bret Cahill
Mar 29, 2022, 10:11:32 PM3/29/22
to
> So stable. So berry stabil. Bang!
>
> <https://earthobservatory.nasa.gov/images/149640/ice-shelf-collapse-in-east-antarctica/>
>
> Ice Shelf Collapse in East Antarctica
>
> The shelfs disintegration in March 2022 has reshaped a landscape where
> coastal glacial ice was once thought to be stable.
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