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baking

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Re: Thwaites Glacier Discussion
« Reply #150 on: October 14, 2019, 09:49:23 PM »
baking,
I have to wait for clear pictures from Sentinel to do an evaluation of the things that are going on.

I get all of my images from polarview.org.  I have not had much success with other sources and I find Polar View to be "good enough" for what I'm doing.

baking

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Re: Thwaites Glacier Discussion
« Reply #151 on: October 19, 2019, 05:12:04 AM »
This will be the first in a short series of posts which will attempt to overlay published bathymetry and grounding line data on recent Sentinel-1 satellite images.

I will start with the bathymetry map found in Millan 2017 "Bathymetry of the Amundsen Sea Embayment sector of West Antarctica from Operation IceBridge gravity and other data"
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL072071

The first image below is box (b) "Thwaites/Haynes" from figure 2.

The second is the matching Sentinel-1 "Extra Wide Mode" image from October 16, as processed by Polar View.

The third is the bathymetry overlaid over the satellite image at 50% opacity.  Grounding line positions are red (year 1996), ice front positions (year 2008) are yellow. Bed elevation is color coded from light blue to dark blue (−1400 m), with light contours every 100 m and thick contours every 400 m (300, 700, 1100 m) although the light contour lines are very faint in the overlay.

The next step will be to update the grounding lines from Milillo 2019 "Heterogeneous retreat and ice melt of Thwaites Glacier, West Antarctica"
https://advances.sciencemag.org/content/5/1/eaau3433

For those that are interested, here is the process that I used to generate these images.  Anyone with minor proficiency in GIMP or any similar image processing software (Photoshop, etc.) should be able to duplicate this and verify my results.

Start by downloading this Sentinel-1 image from Polar View (available for 30 days): https://www.polarview.aq/images/105_S1jpgfull/S1B_EW_GRDM_1SSH_20191016T041914_9DC8_S_1.final.jpg

If you wish to use another image, make sure that the full rectangle, 100 to 110 degrees West and 74 to 75 degrees South is visible.  Your scaling numbers may vary slightly from the ones below.

Download Figure 2 from Millan 2017 (link above) using the "Open in Figure Viewer" link then "Save Image as..."

I opened the satellite image in GIMP first and then "Open as Layers..." Figure 2.  (It only works in that order because the satellite image is larger.)

I measured the 100 to 110 degrees West and 74 to 75 degrees South rectangle in both images and estimated that I needed to scale the satellite image down by a factor of 4.46.  (I confess that this calculation was non-trivial, but the results were surprisingly good.)  I scaled the image from 14060x14406 to 3152x3230.

Then I just reduced the opacity of the top layer to 50% and lined up the corners of the rectangle.  It was not off by more than a pixel so I was happy.  Finally I cropped to image to the edges of the black box (b) and saved it.

Let me know if you have any problems duplicating this.

baking

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Re: Thwaites Glacier Discussion
« Reply #152 on: October 19, 2019, 08:09:34 AM »
A quick update.  I was able to fairly easily (details below) add the grounding lines through late November 2017 (2017.91 in decimal years) as a very faint (30% opacity) overlay.  It's a very busy diagram, but I hope at some point to be able to mask out the extraneous details and increase the opacity.

In general, I was quite surprised at the size of the ground line retreat.  Seeing it laid on top of the satellite images I have grown quite familiar with was a bit of a shock.  Also, at first glance, it would appear that there has been some additional grounding line retreat in the last two years.  In particular, the West side of the "Butterfly" looks like it is no longer grounded, although it should probably be compared to older satellite images to see if it is a new feature or not.

Edit: Added an annotated version.

This is Figure 1(B) from Milillo 2019 "Heterogeneous retreat and ice melt of Thwaites Glacier, West Antarctica"
https://advances.sciencemag.org/content/5/1/eaau3433

The only way I found to obtain a high resolution image of the figure was to click on the "View this article with LENS" button, then click on "Figures" and click on Figure 1.  I cropped and masked the figure to just get the bathymetry, then rotated it clockwise 70 degrees and scaled it down 4% (0.96 scaling.)  The 1996 grounding lines then lined up quite nicely, yellow in Milillo and Red in Millan.
« Last Edit: October 19, 2019, 08:32:29 AM by baking »

baking

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Re: Thwaites Glacier Discussion
« Reply #153 on: October 29, 2019, 09:21:04 PM »
This is a follow up to Reply #132 about the underwater peaks under Thwaites Tongue and the effects they have had over the past two weeks.  The concern is that the peaks will cause shearing of the Western side of the Tongue.  Already we can see increased rifting from what had occurred before.

The first image is a radar image from Sentinel-1 taken on October 26, 2019.  It shows the approximate location of the highest two peaks identified previously, and cracks and rifts that have widened significantly since October 14.

The second is a 3 image GIF from October 14, 20, and 26.  The motion is relative to the rest of the Tongue, not absolute, to better see the effect of the rifting.

baking

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Re: Thwaites Glacier Discussion
« Reply #154 on: November 02, 2019, 04:52:49 AM »
Here is an updated GIF through November 1, showing the rifting in the Tongue described in the post above which is showing no sign of slowing down.

Tor Bejnar

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Re: Thwaites Glacier Discussion
« Reply #155 on: November 02, 2019, 02:23:06 PM »
Baking's 2nd image (the GIF) shows the latitude or longitude line moving about.  It appears the one iceberg that moves the most in the GIF moves in sync with with red line, suggesting everything else is 'actually moving' and that one berg is (relatively) standing still.  An alternate interpretation would be the red line is approximate (and therefore is not stationary): if so why include it in the first place?  (I know this is not Baking's doing.)

Other that that, I really appreciate Baking's close look at the relative movements of the mostly glued-together icebergs.
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baking

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Re: Thwaites Glacier Discussion
« Reply #156 on: November 02, 2019, 04:03:29 PM »
Baking's 2nd image (the GIF) shows the latitude or longitude line moving about.  It appears the one iceberg that moves the most in the GIF moves in sync with with red line, suggesting everything else is 'actually moving' and that one berg is (relatively) standing still.  An alternate interpretation would be the red line is approximate (and therefore is not stationary): if so why include it in the first place?  (I know this is not Baking's doing.)

Other that that, I really appreciate Baking's close look at the relative movements of the mostly glued-together icebergs.

Great questions, Tor.  I tried to explain in the post before that these GIFs are relative to the regular movement of the Tongue.  The red line is the 75 South line of latitude, so its movement in the GIF reflects the absolute motion of the Tongue.  The lone iceberg that is moving with the line is in fact grounded and has been for over a year.  It rests on a underwater peak and there is another peak directly above it in the GIF, just below the midline where you can see cracks widening.  This second peak is also responsible for the expansion of the rifts to the right (South or upstream.)

Most of my GIFs show absolute motion, but this is one case where the relative motion is more subtle and easier to see with movement of the main flow removed.  Make sure you follow the discussion at Reply #132 and above and don't hesitate to ask any questions.  I'd be happy to clarify.

The significance of this is best highlighted in this GIF https://twitter.com/StefLhermitte/status/1101870380623511552 which shows how the underwater peaks shear lines of icebergs off the Western side of the Tongue making it ever thinner.

All of my pictures are from PolarView.aq who are responsible for the lines of latitude and longitude for which I am forever grateful.

Tor Bejnar

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Re: Thwaites Glacier Discussion
« Reply #157 on: November 02, 2019, 05:13:16 PM »
Thanks!
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baking

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Re: Thwaites Glacier Discussion
« Reply #158 on: November 09, 2019, 12:46:55 AM »
Here is a quick update on the Western side of Thwaite's Tongue.  I'm only showing two images in this GIF, November 1 and 7, to emphasize that the rifting is still continuing to expand at a rapid rate.  All motion here is relative.

If the underwater peak continues to push against the Tongue, you can see where a row of icebergs, 3-4 across, will be stripped off reducing the Tongue's width by about a third.

baking

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Re: Thwaites Glacier Discussion
« Reply #159 on: November 13, 2019, 09:49:40 PM »
Another 6-day Sentinal-1 radar update on the rift in the Western side of Thwaites Tongue.  This GIF shows the last 3 months.  Motion is relative to the Tongue.  This rifting is being caused by an underwater peak just to the left of the red latitude line

baking

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Re: Thwaites Glacier Discussion
« Reply #160 on: November 18, 2019, 05:15:53 PM »
For those that like the Sentinel-2 MultiSpectral Instrument (MSI) images, here is the Tongue rift between 11/12 and 11/17.  Rendering is Normalized Difference Water Index (NDWI) which I find gives me the best results.  We should have another Sentinel-1 radar image tomorrow for comparison.

baking

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Re: Thwaites Glacier Discussion
« Reply #161 on: November 20, 2019, 06:45:30 AM »
New Sentinal-1 radar image from November 19 shows the Western Tongue Rift continues to widen over the past 6 days.  A new fracture perpendicular to the main rift at it widest point is now evident, highlighted in the second picture, giving further evidence of breakup.

kassy

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Re: Thwaites Glacier Discussion
« Reply #162 on: November 22, 2019, 02:03:42 PM »
Pathways of ocean heat towards Pine Island and Thwaites grounding lines

...

In this study, we use an unprecedentedly high-resolution (200 m horizontal and 10 m vertical grid spacing) ocean model that resolves shelf-sea and sub-ice-shelf environments in qualitative agreement with existing observations during austral summer conditions. We demonstrate that the waters reaching the Pine Island and Thwaites grounding lines follow specific, topographically-constrained routes, all passing through a relatively small area located around 104°W and 74.3°S. The temporal and spatial variabilities of ice shelf melt rates are dominantly controlled by the sub-ice shelf ocean current. Our findings highlight the importance of accurate and high-resolution ocean bathymetry and subglacial topography for determining mCDW pathways and ice shelf melt rates.

...

https://www.nature.com/articles/s41598-019-53190-6
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baking

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Re: Thwaites Glacier Discussion
« Reply #163 on: November 23, 2019, 03:45:18 PM »
For those that like natural color images, here is a 10-day movement of the Western Tongue Rift between November 12 and 22.

Stephan

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Re: Thwaites Glacier Discussion
« Reply #164 on: November 23, 2019, 07:38:54 PM »
Thank you for that animation.
I wonder once those bergs will be drifting away whether the rest of the ice tongue will remain stable or if the next row of bergs will start to move.
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Tor Bejnar

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Re: Thwaites Glacier Discussion
« Reply #165 on: November 23, 2019, 09:09:17 PM »
Stephan,
Those frozen-together floes that 'don't move' in Baking's posts are actually moving already - he just adjusts the images to emphasize the difference between the accelerating lead floes and the others.  Look up thread at his November 20 GIF that includes a latitude or parallel line.  The line actually isn't moving across the Earth, all the ice is.

This is frequently done to show relative changes in rifts on glaciers.  Glaciers move every day, but most of the ice moves in tandem with its neighboring ice.   By moving a 2nd image so that certain features exactly cover each other, other features are obvious.
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baking

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Re: Thwaites Glacier Discussion
« Reply #166 on: November 23, 2019, 09:15:35 PM »
I wonder once those bergs will be drifting away whether the rest of the ice tongue will remain stable or if the next row of bergs will start to move.

This row is being forced out by an underwater peak near the top crack in the GIF.  It is possible that in time the next row will be forced out by that same peak.  Another possibility is that this narrowing of the Tongue will create so much instability that the entire Tongue will float off in pieces or that the Tongue will lose it's leading end and it won't be long enough to maintain contact with the ridge that has helped to hold it in place.

Stephan

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Re: Thwaites Glacier Discussion
« Reply #167 on: November 23, 2019, 09:49:50 PM »
Stephan,
Those frozen-together floes that 'don't move' in Baking's posts are actually moving already - he just adjusts the images to emphasize the difference between the accelerating lead floes and the others.  Look up thread at his November 20 GIF that includes a latitude or parallel line.  The line actually isn't moving across the Earth, all the ice is.

This is frequently done to show relative changes in rifts on glaciers.  Glaciers move every day, but most of the ice moves in tandem with its neighboring ice.   By moving a 2nd image so that certain features exactly cover each other, other features are obvious.
I of course know that and by adjusting the pictures in such a way as baking did it the "extra" movement (in this case westward) is obvious. This "extra" movement of further bergs in the ice tongue I was asking for - baking has already answered this question (see posting above).
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Tor Bejnar

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Re: Thwaites Glacier Discussion
« Reply #168 on: November 23, 2019, 11:32:07 PM »
I'm glad you knew, Stephan.  I've been sick and didn't have the energy to point to Baking's reply to my earlier surmise clarifying all that.
Cheers (even if subdued!),
Tor
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blumenkraft

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Re: Thwaites Glacier Discussion
« Reply #169 on: November 24, 2019, 05:29:58 AM »
Oh man! Get well soon, Tor.
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Andreas T

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Re: Thwaites Glacier Discussion
« Reply #170 on: November 24, 2019, 10:08:31 PM »
B22A has been moving more than it has in the last few years I think. This has of course not much significance since it is just a stranded iceberg but as a start to the season it makes one wonder what effect it may have on the fast ice between it and the coast.
https://go.nasa.gov/2DeQwLr

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Re: Thwaites Glacier Discussion
« Reply #171 on: November 25, 2019, 05:34:05 PM »
Great find, Andreas.

I took every cloud-free(ish) Sentinel shots since September.
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baking

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Re: Thwaites Glacier Discussion
« Reply #172 on: November 25, 2019, 06:26:57 PM »
Here is the latest 3-month GIF of Sentinel-1 radar images of the Western Tongue Rift as of today.

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Re: Thwaites Glacier Discussion
« Reply #173 on: November 25, 2019, 06:32:00 PM »
How would you evaluate the influence of the sea ice? In other words, would the "peeling off" of the icebergs happen faster if there were no sea ice W of Thwaites Ice Tongue?
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baking

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Re: Thwaites Glacier Discussion
« Reply #174 on: November 25, 2019, 06:36:56 PM »
B22A has been moving more than it has in the last few years I think. This has of course not much significance since it is just a stranded iceberg but as a start to the season it makes one wonder what effect it may have on the fast ice between it and the coast.

B22Ahas shifted significantly to the NW in the last week.  As mentioned previously in this thread, moves to the West or Northwest are not very concerning because it is just further grounding.  Moves to the East or Northeast are cause for concern because that would be towards deeper water.  The previous shift to the NW was followed by a smaller move to the East I think.  Probably worth a longer-term analysis to see what has been happening so far this season.

baking

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Re: Thwaites Glacier Discussion
« Reply #175 on: November 25, 2019, 06:52:57 PM »
How would you evaluate the influence of the sea ice? In other words, would the "peeling off" of the icebergs happen faster if there were no sea ice W of Thwaites Ice Tongue?

My Reply #111 from September 26 kind of ties this discussion with the iceberg B22-A thread.

Basically, my conclusion there was that the sea ice was holding back parts of the Tongue from breaking off.  Once we see the sea ice clear as we get into January and February "loose" pieces of the Tongue may just float off.

This rift is being driven by a irresistible force (Thwaites Glaicer) hitting an immovable object (an undersea ridge) so this rift is probably going to continue to widen no matter the condition of the sea ice.  But these pieces that are getting knocked loose will be much more vulnerable when the sea ice goes away.  And the remaining parts of the Tongue might also be less stable.

If you look at the recent history in the link below, large rafts of icebergs of icebergs tend to drift off together, so the Tongue will most likely be much smaller in six months.

https://twitter.com/StefLhermitte/status/1101870380623511552

baking

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Re: Thwaites Glacier Discussion
« Reply #176 on: November 26, 2019, 01:16:44 AM »
I have overlaid a recent bathymetric chart over a Sentinel-1 radar image of B22-A from November 21, that shows the iceberg is probably grounded in two locations.  In the West and a large shallows area and in the East on a smaller peak.  Both are higher than 300 meters below the surface.

When looking at movements of B22-A it should be useful to have these reference points in mind.  I will make another post detailing the recent movements of B22-A, but as a first pass the iceberg seems to be pivoting on the Western shallows and the Eastern end is rotating counter-clockwise to the North.  This means that it is moving over the Eastern Peak, but it far from moving off the peak.

I note that the trough under the middle of B22-A means that is the most likely place for basal melting and the possibility of the iceberg splitting into two pieces has to be considered.

Millan 2017: "Bathymetry of the Amundsen Sea Embayment sector of West Antarctica from Operation IceBridge gravity and other data"
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL072071

baking

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Re: Thwaites Glacier Discussion
« Reply #177 on: November 26, 2019, 08:42:12 AM »
Here is one series of Sentinel-1 radar images of Iceberg B22-A.  This one has huge gaps, and I can probably find a longer series, but I think it makes a good representation.

There is a lot of back-and-forth motion from East to West.  It's almost like the iceberg is caught between the two shallow areas and is just drifting back and forth between them, with currents or the tide.  That movement is minor, roughly a kilometer, but it does seem to imply that B22-A is no longer firmly grounded.

Over time there is also a gradual counter-clockwise rotation to the North.  One could imagine that as B22-A bounces back and forth in a tight space it is also slowly working its way lose, although I still think it was a long way to go if it is going to work free without breaking up.

If it does break in two, the smaller halves might be less constrained and will have more freedom of motion to drift off.

This GIF has one image from March 8, 5 images from September 16 through October 10, and 5 more images from October 28 to November 21.  There is a pause before each gap and at the end.  The things to note are the gradual movement to the North (right to left) and small back-and-forth motions East and West (up and down.)  Also, it tends to pivot counter-clockwise around the Western (bottom) end.

Stephan

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Re: Thwaites Glacier Discussion
« Reply #178 on: November 26, 2019, 08:24:19 PM »
Thanks a lot, baking for the bathymetry map and the gif.
If I understand correctly B-22A must turn clockwise by about 110° to be in line with the trough which would allow it to be exported into deeper seas northward. But this will probably not happen with dominant SE winds and currents.
In the end it will sit there for a longer while moving back and forth a little bit until it melts sufficiently and gets unpinned or until it breaks into smaller more mobile parts.
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Re: Thwaites Glacier Discussion
« Reply #179 on: December 05, 2019, 09:26:56 AM »
New study models impact of calving on retreat of Thwaites Glacier

Link >> https://blogs.agu.org/geospace/2019/12/04/new-study-models-impact-of-calving-on-retreat-of-thwaites-glacier/
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Re: Thwaites Glacier Discussion
« Reply #180 on: December 06, 2019, 08:08:08 AM »
There is a nice paper from the same gang in 2018 that illuminates this paper.

doi:10.5194/tc-12-3861-2018

open access, chekitout.

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baking

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Re: Thwaites Glacier Discussion
« Reply #181 on: December 06, 2019, 03:39:03 PM »
There is a nice paper from the same gang in 2018 that illuminates this paper.
The newer paper isn't on sci-hub yet, but the older paper notes this limitation of their model:

"Another limitation is that the ice shelf front migration is not included in our simulations. We assume that the ice shelf front position of TG remains fixed; i.e., all ice passing the ice shelf front calves immediately. Densely distributed crevasses along the ice shelf of TG, however, make the ice shelf conducive to rapid calving (Yu et al., 2017). Once the ice shelf is removed, the grounding line will retreat into deeper regions, and the probability of calving increases according to the marine ice-cliff instability theory (Pollard et al., 2015; Wise et al., 2017). Crevassing and calving will therefore reduce ice shelf buttressing and accelerate ice speed; i.e., our simulations underestimate the potential mass loss of TG (MacGregor et al., 2012). On PIG, calving has increased in frequency and its ice front is now 35 km farther inland on the eastern side than in the 1940s (Jeong et al., 2016; MacGregor et al., 2012). On TG, the floating ice tongue in the center trunk retreated by 26 km from 1973 to 2009 (MacGregor et al., 2012). The eastern ice shelf has been thinning and retreating, which means that the ice shelf could disintegrate in the coming decades."

Presumably, the newer paper addresses this issue and is "the other shoe" that we've been waiting to drop.

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Re: Thwaites Glacier Discussion
« Reply #182 on: December 07, 2019, 09:14:57 PM »
The actual EOSDIS picture shows a further "peeling-off" of the row of icebergs from the Thwaites Ice Tongue (see postings in this thread above). The change of flow direction (green arrows) is marked by a dotted red line. This line has further widened and open water is visible.
Further east, there is a change in flow speed at the western edge of Thwaites Eastern Ice Tongue (TEIS), marked with a dotted green line.

See attached picture, looking forward to an actual Sentinel picture of that area in the next days...
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baking

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Re: Thwaites Glacier Discussion
« Reply #183 on: December 07, 2019, 11:18:32 PM »
. . . looking forward to an actual Sentinel picture of that area in the next days...

Here is today's Sentinel-1 radar image compared with 12 days ago.  Fairly substantial movement, but nothing "surprising" to anyone who has been following along.

Darvince

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Re: Thwaites Glacier Discussion
« Reply #184 on: December 08, 2019, 09:44:15 AM »
Is that a slight rotation of the main body of the tongue I see?

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Re: Thwaites Glacier Discussion
« Reply #185 on: December 08, 2019, 12:13:13 PM »
I would be careful with such an interpretation. Baking has adjusted the pictures in that gif to the movement of the ice tongue (visible in the shift of the red latitude line). Depending on which floe he chose to make that adjustment it may be that others' flows slightly differs - therefore a kind of rotation appears, although it objectively doesn't happen.
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Darvince

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Re: Thwaites Glacier Discussion
« Reply #186 on: December 08, 2019, 01:17:57 PM »
Taking a closer look at their previous posts makes me think that you are correct and that it is indeed nothing; baking's previous GIFs seem to show a similar amount of noise.

Actually, after a second and even closer look, the main body of the tongue does appear to have begun rotating in the last month or so of their last GIF, after the relative motion of the soon-to-break-away armada picks up again. Could this also be from the same underwater feature as what's causing the breakaway?

baking

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Re: Thwaites Glacier Discussion
« Reply #187 on: December 08, 2019, 03:59:20 PM »
Nice catch, Darvince.  Yes, these images are overlaid to show relative motion, but I only do an X-Y move, I don't correct for any rotation.  So any rotation you are seeing is real, or at least the result of a curved trajectory.

The main explanation seems to be that the "Melange" caught between the Thwaites Eastern Ice Shelf (TEIS) and the Tongue is pushing against the Tounge from the East (top) and causing the Tongue to turn slightly to the West.

Specifically, the Tongue is driving a wedge into a large mass of ice caught behind a 10 km long "cork" and part of that ice is being forced against the Eastern side of the Tongue.  See the image below.

This has been going on for at least a year, but a few months ago the cork started moving and the rotation was lessened.  However in the last two weeks the cork has become hung up again on some different pieces of ice and the rotation has returned.  One caveat is that there seems to some visual effect (artifact) in the radar images of the "shadows" between the icebergs in the latest image that may be misleading about small motions.

But yes, there is a rotation and it has been there for a while.  It may continue if the cork becomes stuck again.  It doesn't seem to have anything to do with the underwater peaks, except that the rotation may be forcing the Tongue on to the peaks and causing the premature break-up.  The Tongue is fragile enough that it will break before it bends.

baking

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Re: Thwaites Glacier Discussion
« Reply #188 on: December 08, 2019, 04:34:11 PM »
I should add that I have been very concerned about a potential weakness in the Tongue in the area circled in the detailed image below.  I do note that it is between the peak and the point where the melange is forcing against the Tongue (arrow.)  Basically, the fear is that it could cause major East-West rifting in the Tongue and effectively cut its length in half.

So, if the "cork" gets stuck again this might be a major risk.  Of course if the cork doesn't get caught and floats off free the melange might also float off and then who knows what will happen to the stability of the Tongue and the Eastern Ice Shelf.

baking

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Re: Thwaites Glacier Discussion
« Reply #189 on: December 08, 2019, 05:06:45 PM »
I thought I would show a long-term GIF to demonstrate what I've been talking about.  It shows the "wedge" being driven into the ice mass and the pressure point is causes on the Tongue.  All motion is relative to the Tongue, so things you see moving left to right are moving slower than the Tongue.

There are three phases to the GIF: 1) February-August The wedge is being driven into the ice mass, 2) September The ice mass pushes "down" on the Tongue, and 3) October-November The "cork" comes free (not shown) and everything moves along with the Tongue so there is little relative motion.

It may not be a coincidence that the "cork" pops free just as the melange starts to push hard against the Tongue.  It could be that the Tongue pushing back put enough pressure on the cork.

EDIT: See my Reply #142 from October 13 for a GIF of the "cork" coming loose.
« Last Edit: December 08, 2019, 05:17:12 PM by baking »

blumenkraft

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Re: Thwaites Glacier Discussion
« Reply #190 on: December 08, 2019, 05:53:20 PM »
Amazing!

Thank you, Baking!
Refugees welcome

baking

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Re: Thwaites Glacier Discussion
« Reply #191 on: December 11, 2019, 05:23:40 PM »
We finally have boots on the ice for the 2019/2020 research season!

https://twitter.com/Alpinesciences/status/1204548226466156546

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