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Stephan

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Crosson and Dotson Ice Shelves
« on: February 13, 2020, 07:18:19 PM »
PIIS has pulled all attention in the last weeks, but a few 100 km west another ice shelf had a major calving event.
Between Feb 1 and Feb 11 a part of the Dotson Ice Shelf lost a 25*3 km piece of ice. The days in-between were too cloudy for an evaluation in EOSDIS, so a more exact dating is not possible.

See attached image.
« Last Edit: March 25, 2022, 09:38:09 AM by oren »
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grixm

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Re: Dotson Ice Shelf has calved
« Reply #1 on: February 13, 2020, 08:16:52 PM »
Quote
Between Feb 1 and Feb 11 a part of the Dotson Ice Shelf lost a 25*3 km piece of ice. The days in-between were too cloudy for an evaluation in EOSDIS, so a more exact dating is not possible.

To me it looks like it had already calved by the 1st. It had moved considerably by then if you compare it to a week or so before. It just hadn't completely drifted away from the shelf yet.

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Re: Dotson Ice Shelf has calved
« Reply #2 on: February 13, 2020, 08:24:09 PM »
Yes, happened between 21. and 25. according to the radar pics. I would post a GIF but EZGIF doesn't like me today.

But Kudos, Stephan, for finding it!
« Last Edit: February 13, 2020, 08:30:26 PM by blumenkraft »

paolo

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Re: Dotson Ice Shelf has calved
« Reply #3 on: February 13, 2020, 10:18:27 PM »
Stephan,
Good point!  ;)

Couldn't we rename this forum "Crosson and Dotson Ice Shelfs Discussion"?
Intended therefore to host any discussion on these two ice platforms and the glaciers feeding them, which would give us, relative to the Admunsen Sea Embayment, 
"PIG has calved" dedicated to the PIIS and its tributaries, which I'll see renamed "PIG Discussion".
"Thwaites Glacier Discussion"
"Crosson and Dotson Ice Shelfs Discussion"
"Getz Ice Shelf - Iceberg B-47", which I'll see renamed to "Getz Ice Shelf Discussion".
And all that will be left to do is to create the last "Abbot and Cosgrove Ice Shelfs Discussion" when the opportunity arises.

Stephan

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Re: Dotson Ice Shelf has calved
« Reply #4 on: February 13, 2020, 10:30:14 PM »
How can I rename a thread I opened?
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Tor Bejnar

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How to change 'Subject' to "Crosson and Dotson Ice Shelfs Discussion"
« Reply #5 on: February 14, 2020, 12:47:19 AM »
Change the "Subject" in the first post.  If the 'statue of limitations' prevents this, contact Neven.  He's Superman - he can do things no ordinary person can do (on this forum). ;)

(Anybody can change the subject in their own posting, but it doesn't affect any subsequent thread entry.)
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Stephan

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Re: Crosson and Dotson Ice Shelfs Discussion
« Reply #6 on: February 14, 2020, 07:00:48 AM »
Thanks. Done.
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Stephan

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #7 on: January 17, 2022, 07:30:02 PM »
Micro calving at Dotson Ice Shelf.
The orange circled part of the shelf has disappeared.
The picture is from Dec. 01. A clear Sentinel picture from after the calving is not available, but you can see through the clouds that this part is missing. The calving is verified in EOSDIS worldview.
The scale of this calving is around 6*1 km.

See attached picture.
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FredBear

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #8 on: January 18, 2022, 01:31:39 AM »
Micro calving at Dotson Ice Shelf.
The orange circled part of the shelf has disappeared.
The picture is from Dec. 01. A clear Sentinel picture from after the calving is not available, but you can see through the clouds that this part is missing. The calving is verified in EOSDIS worldview.
The scale of this calving is around 6*1 km.

I cannot see much change in the edge - there is a little bit of "breathing in/out" (may be mist/fog/cloud/crumbling ice on the margin?) that I can see on Worldview from 01/12/2021 until 07/01/2022, but then a slight change from convex to concave (c. 600m) by 11/01/2022 (with debris out to sea?), is that what you saw?

(N.B. I nearly got caught by Worldview on 13 January - the ice edge "jumped" about 2km in the eastern Ross Sea relative to the marked ice edge, then went back the following day! This variation extends from west of the Getz ice shelf to just past Roosevelt Island but I don't like/know who to comment to officially - Worldview is a wonderful daily resource.)

Stephan

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #9 on: January 18, 2022, 07:29:09 PM »
If you go to EOSDIS and use the comparison mode then you can see that the calving must have taken place between Jan 7 and Jan 11 under cloudy conditions.
To be sure that no fast ice or sea ice has been lost I checked with Sentinel pictures which revealed that the missing part was really a part of the ice shelf. This part was already divided by a large rift on its eastern half on Dec 01, 2021.

https://worldview.earthdata.nasa.gov/?v=-1688001.203307675,-714642.5242104544,-1521089.203307675,-625426.5242104544&p=antarctic&l=Coastlines_15m,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor&lg=false&l1=Coastlines_15m,VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor&lg1=false&ca=true&cv=53&t=2022-01-07-T21%3A05%3A25Z&t1=2022-01-11-T16%3A14%3A38Z
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IceConcerned

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #10 on: January 21, 2022, 11:18:39 AM »
In the meantime, Crosson is moving and evolvilng. On the attached gif, we can see that the ice sheet is fracturing more, while the two icebergs that were stuck in front are moving (first north, but fot the past months rather westwards) and begin to disintegrate. All movements seem to be accelerating.
The gif starts with history going back to the beginning of 2019, and the last frames to show the recent evolution I am talking about.
This is my first ever animated gif, so I am receiving with gusto all advice and comment

IceConcerned

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #11 on: January 21, 2022, 05:07:25 PM »
And further south, the ice sheet is opening, with the icebergs calved from Thwaites westernmost parts and the northern Crosson ice sheet moving north, while the eastern component of Crosson IS (close to Tha=waites) is moving rather NE-wards and detaching.
In the end I suspect this might create an opening for the glacier behind to disgorge more quickly, even without the full ice sheet desintegrating.

oren

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #12 on: January 21, 2022, 08:46:22 PM »
Great animations. The long-term view is very helpful.
Peraonally I would prefer them slowed down a bit, somewhat increasing the delay between frames, and perhaps increasing the pause on the last frame.

Stephan

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #13 on: February 04, 2022, 08:48:37 PM »
For the latest calvings see replies #502 and #509 in the "Antarctic icebergs thread"
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interstitial

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #14 on: February 04, 2022, 11:33:05 PM »
Great animations. The long-term view is very helpful.
Peraonally I would prefer them slowed down a bit, somewhat increasing the delay between frames, and perhaps increasing the pause on the last frame.
Ditto

paolo

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #15 on: February 12, 2022, 06:55:53 PM »
An interesting paper on the Pope, Smith East and West, and Kohler glaciers was published in January in the journal "Nature geoscience":
Milillo et al (2022), "Rapid glacier retreat rates observed in West Antarctica"

"Located on the western flank of the ASE (Amundsen Sea Embayment), the Pope, Smith and Kohler glaciers drain 7% of the ASE into the Crosson and Dotson ice shelves but contribute 24% of the total loss from ASE, with an average 32 Gt yr–1 mass loss during the period 1979–2017."

"A number of changes were noted in previous studies of these glaciers. At the grounding line (where ice detaches from the bed and becomes afloat), the velocity of Pope Glacier increased from 370 m yr–1 in 1989 to 775 m yr–1 in 2016, which doubled its ice discharge from 5.5 ± 0.6 to 9.5 ± 0.7 Gt yr–1. Near the grounding line, grounded ice thinned at 9 m yr–1 between 2003 and 2008 while floating ice melted at 40 m yr–1. The grounding
line retreated at 0.64 km yr–1 from 1996 to 2014. On Smith East and West, the velocity increased by 280% (710 m yr–1) and 370% (800 m yr–1), respectively, in 1992–2015, which tripled their combined ice discharge as the grounding line retreated into thicker. Between 2002 and 2009, Smith West thinned at 7 m yr–1 on grounded ice and melted at 70 m yr–1 on floating ice. From 1992 to 2016, the grounding line of Smith West retreated at 2 km yr–1,
which was the fastest retreat rate in Antarctica, while Smith East retreated at 0.5 km yr–1. By contrast, Kohler exhibited no speed up between 1994 and 2016, and its grounding line migrated back and forth between 1996 and 2014."

"The Pope, Smith East and West, and Kohler glaciers control a drainage area with an ice volume above flotation equivalent of 6 cm global sea-level rise, which is small, so the risks of rapid sea-level rise from this sector of West Antarctica are low. Yet the physical processes driving their retreat are the same that operate on neighbouring Thwaites and Pine Island, which hold a 1.2 m global sea-level rise and may destabilize the rest of West Antarctica. Understanding the physical processes driving the fast retreat of Pope, Smith and Kohler, especially the magnitude of ice melt in the grounding zones, is therefore critical to explain and reproduce the observed rates of retreat. The results will in turn help reduce uncertainties in the upper bounds of maximum contribution to sea-level rise from West Antarctica in decades to come."


Click twice to enlarge completely


steve s

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #16 on: February 12, 2022, 07:42:30 PM »
The Pope, Smith East and West, and Kohler glaciers have headwaters on Mt Takahe. Takahe is an active volcano, so elevated basal warming is likely to be causing the fast melt relative to the Thwaites.

paolo

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #17 on: February 12, 2022, 08:23:29 PM »
Disagree completely: the basal melt is at the level of the ice shelf, it is zero upstream.

The thinning upstream of the grounding line is the dynamic thinning due to the change in speed, hence the formula used by the authors for the grounded part:
    Thinning rate = dynamic thinning + surface mass balance

Melting occurs downstream of the grounding line, hence the formula used by the authors for the floating part:
    Thinning rate = dynamic thinning + surface mass balance + ice shelf melt
and it is massive!

"The highest thinning rates are observed in areas of freshly ungrounded ice and are caused by a combination of dynamic thinning and bottom melt by the ocean waters (surface mass balance is less than 0.5 m yr–1 in this region, hence is not a factor). On land, dynamic thinning equals the rate of ice thinning, which we calculate over grounded ice adjacent to the freshly ungrounded. We assume that the same rate of dynamic thinning applies on ungrounded ice, subtract this rate from the observed rate of ice thinning, assume hydrostatic equilibrium and deduce the resulting bottom melt rate. Ice deviates from flotation by only a few metres due to bending stresses in these regions. Above the 2020 grounding lines, we detect ice thinning at 4 to 7 m yr–1 on Pope, Smith and Kohler glaciers and peak values of 9 m yr–1 on Smith West in 2011–2014. For ice that ungrounded on Pope in 2014–2017, we calculate a bottom melt rate of 86 ± 9 m yr–1. On Smith East, dynamic thinning of 5 m yr–1 in 2011–2019 on grounded ice translates into a melt rate of 22 ± 6 m yr–1 on freshly ungrounded ice. For Smith West, grounded ice thinning at 6 ± 0.4 m yr–1 yields a 65 ± 6 m yr–1 melt rate of ungrounded ice. For Kohler, grounded ice thinning at 3–4m yr–1 yields 19± 7 m yr–1 melting of ungrounded ice."

sidd

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #18 on: February 12, 2022, 10:07:54 PM »
There was a paper by Robel posted in the Ice Apocalypse thread indicating that seawater intrusion inland of the grounding line accentuates basal melt upstream of the grounding line, especially on impermeable beds. So not all thinning upstream may be dynamic. In that paper there is also a reference to the millilo paper discussion of thwaites.

https://tc.copernicus.org/articles/16/451/2022/

sidd

steve s

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #19 on: February 12, 2022, 10:31:21 PM »
Pablo, I agree that we disagree. And for reasons apart from seawater intrusion under the glacier. On the methods employed in the research:

"On land, dynamic thinning equals the rate of ice thinning, which we calculate over grounded ice adjacent to the freshly ungrounded. We assume that the same rate of dynamic thinning applies on ungrounded ice, subtract this rate from the observed rate of ice thinning, assume hydrostatic equilibrium and deduce the resulting bottom melt rate. Ice deviates from flotation by only a few metres due to bending stresses in these regions."

The article deals with an out-of-equilibrium speed up. Since the authors deduced their conclusions for each glacier by expanding on single measurements by using equilibrium assumptions, validating their methods must include demonstrating that each glacier was originally at and has again achieved an idealized plastic flow form. Until that's been demonstrated, geothermal heat is not off the table as a root cause of the higher flow rates.

paolo

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #20 on: February 13, 2022, 02:49:35 AM »
To simplify a little: the authors start with the equation :
     Thinning rate = dynamic thinning + surface mass balance + ice melt,
which they use in the vicinity of the grounding line, and make the following assumptions:
> "surface mass balance is less than 0.5 m yr-1 in this region, hence is not a factor"
> "We assume that dynamic thinning does not change rapidly in space as ice ungrounds over length scales of a few ice thickness. We confirm this by verifying that the grounded ice thinning rate in a box adjacent to the 2020 grounding line is similar to that calculated in a nearby box on ice that becomes ungrounded during the observation period."
> The authors also state that the ice melt upstream of the grounding line is negligible (but this is not explained).
This allows them, by using the equation upstream of the grounding line and downstream (but remaining in the vicinity of the grounding line) and determining the thinning rate from the satellite measurements to calculate the ice shelf melt

Sidd,
Thank you for reminding me of Robel et al (2022), I had seen it and put it aside to be read.
Indeed we could have a melt upstream of the grounding line, but this would mean an even greater melt downstream of the grounding line

Steve
Even if in the past there had been another source of the thinning rate far upstream of the grounding line and now the thinning caused by it had arrived at the grounding line, in the vicinity of the grounding line it would act in the same way upstream and downstream of the grounding line and it would not change the current value of the ice melt downstream of the grounding line, i.e. the only change would be that some of the dynamic thinning would be replaced by the action of this cause and the ice melt would remain the same.
But what bothers me is that you seem to be questioning the increase in the termic energy of the sea by replacing it with other causes...
A possible increase in geothermal flow and/or lava upwelling are always possible, but they will add up and they do not replace the increase in termic energy of the sea!
PS: "Paolo", not Pablo
« Last Edit: February 13, 2022, 02:55:53 AM by paolo »

steve s

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #21 on: February 13, 2022, 11:16:40 AM »
Paolo (with apologies for my earlier error), It seems to me the statement that "..., the Pope, Smith and Kohler glaciers drain 7% of the ASE into the Crosson and Dotson ice shelves but contribute 24% of the total loss from ASE, ..." explained what the goal of the study was. Namely to explain the differential very high loss rates of grounded ice from those glaciers. I find the differences in the loss rates at different locations hard to explain through flowing sea water alone.

You commented earlier, when first disagreeing with me, "the basal melt is at the level of the ice shelf, it is zero upstream." Later, you seemed to soften your stance, noting "The authors also state that the ice melt upstream of the grounding line is negligible (but this is not explained)." The method of analysis used requires that simplifying condition, but that assumption conflicts with the known subglacial melting patterns that form lakes and rivers under the ice. Releases of the lake waters are associated with decreased glacial mass and faster flows. 

I think attributing all the melting observed to heat supplied through seawater intrusion to the grounding line is questionable at best. So I do not accept their That the region is geothermically active should be a consideration whenever explaining differential melting rates.

oren

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #22 on: February 13, 2022, 11:39:03 AM »
Steve, in order for geothermal flux to explain the situation in this region, there needs to have been some change in said geothermal flux. The phenomenon to be explained is not a high flow rate, but a fast receding of the grounding line and very high thinning rates that happened relatively recently. So the existence of the flux by itself is not enough to explain the change - the flux was already factored into the local equilibrium.
OTOH, changes in seawater temperature and flow patterns are much faster, and are certainly a plausible explanation for changes, although I cannot personally verify or calculate if they actually explain the local change or not, way above my pay grade. But warm CDW has been implicated in changes all across the ASE.
At least according to Wikipedia Mt. Takahe is considered dormant, with the last eruption thousands of years ago. No recent change that I could find.
Differences from Thwaites Glacier can be easily explained by other factors, the coast is not uniform, the bathymetry is not uniform and the ice thickness and breaking patterns are not uniform across different glaciers. This is evidenced in the local region itself when examining the major differences between Smith and Kohler, despite sharing the same geothermal environment.

paolo

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #23 on: February 13, 2022, 02:55:33 PM »
Steve,
First apology: I should have posted the Abstract, but in the rush I didn't.
So I'm fixing it:

"The Pope, Smith and Kohler glaciers, in the Amundsen Sea Embayment of West Antarctica, have experienced enhanced ocean-induced ice-shelf melt, glacier acceleration, ice thinning and grounding-line retreat in the past 30 years. Here we present observations of the grounding-line retreat of these glaciers since 2014 using a constellation of interferometric radar satellites combined with precision surface elevation data. We find that the grounding lines develop spatially variable, kilometre-scale, tidally induced migration zones. After correction for tidal effects, we detect a sustained pattern of retreat coincident with high melt rates of ungrounded ice, marked by episodes of more rapid retreat. In 2017, Pope Glacier retreated 3.5 km in 3.6 months, or 11.7 km yr–1. In 2016–2018, Smith West retreated at 2 km yr–1 and Kohler at 1.3 km yr–1. While the retreat slowed in 2018–2020, these retreat rates are faster than anticipated by numerical models on yearly timescales. We hypothesize that the rapid retreat is caused by unrepresented, vigorous ice–ocean interactions acting within newly formed cavities at the ice–ocean boundary"

This study therefore concerns the grounding line and its surroundings.

Some of the other elements in my post (such as the statement you mention which was taken from the introduction) were added to recall and clarify the context and were information described in the existing literature.

Second apology: When formatting the copy/paste I removed the numerical references, which without the reminder of the references seemed meaningless to the reader. I was wrong, they would have pointed out that these elements were described and demonstrated elsewhere.

Let's get back to the subject
> The input (satellite) data are :
>> the position of tidal deformations
>> the elevation of the ice shelf/sheet
From these elements the authors deduce :
> the position of the grounding line
> the ice shelf melt rate
I think I understand that you are not questioning this.

With regard to the sentence you mention: "..., the Pope, Smith and Kohler glaciers drain 7% of the ASE into the Crosson and Dotson ice shelves but contribute 24% of the total loss from ASE, ..."
The secret of the difference between the 7% and the 24% is to be found in the staggering increase in speed for these glaciers and the equally staggering retreat of the grounding line (which also implies, in the case of a retrograde bed, an increase in the thickness of the ice and thus an even more sustained increase in the discharge): "On Smith East and West, the velocity increased by 280% (710 m yr–1) and 370% (800 m yr–1), respectively, in 1992–2015, which tripled their combined ice discharge as the grounding line retreated into thicker."

As for the rest, Oren has already answered you.

steve s

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #24 on: February 13, 2022, 10:21:07 PM »
Paolo and Oren, I thank you for the discussion. I still feel that the high local rate of ice mass loss is easier to explain by a geothermal source as opposed to an oceanic source in the absence of heat flow data. If local changes in ocean currents are the cause, an explanation would prove useful.

paolo

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #25 on: February 14, 2022, 08:44:41 PM »
Steve,
The cause and explanation is very simple, it is called "retrograde bed slopes" (see the zoom below on the image already published), many articles talk about it and this forum is full of information about the very deleterious effects that retrograde bed slopes can have on glaciers
That's why studies of retrograde bed slope cases are very important.
Let's not forget that the two giants to the east are approaching it (the PIG probably isn't far away at all!)

The question "But what is the difference between the Smith East & Smith West glaciers ?" was valid, questioning the existing scientific literature using a "magic" argument was not.

Click to enlarge


PS: Smith East & Smith West are the two glaciers involved, Pope and Kohler have an almost "normal" history
« Last Edit: February 14, 2022, 08:53:16 PM by paolo »

steve s

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #26 on: February 15, 2022, 10:53:55 AM »
Paolo,

Perhaps the forum seems to be the wrong place for this discussion; but, if I am confused, others may be as well, so let's continue.

Yes the bed is retrograde. That does not change the meanings of "upstream" or "basal heating" or "lake" or "river". The grounding line remains lower than the base of the glacier upstream as it retreats, so water flows downstream under the grounded ice and past the grounding line, possibly in bursts as ice dams break and reform. More water under the ice improves the lubrication, so the ice above flows faster. Increased basal flows imply faster surface ice flows, other things equal.

The presence of a retrograde bed does not seem to change the analysis until the grounding line goes retrograde causing the ice dynamics to change.

The underlying question being addressed is how much of the observed increase in the rate of grounded mass loss is due to an increase in water traveling out to sea below the ice and how much is due to an increase in ice flow rates past the grounding line. I do not believe the article addressed this ratio, instead assigning the entire loss to ice movement by assuming no increase in melting of the grounded ice.

paolo

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #27 on: February 15, 2022, 07:32:22 PM »
Steve,
First point: melting of the ice shelf (I think I understand that you are not questioning this point, but I would prefer to clarify)
Notations: T = Thinning rate, D = Dynamic thinning, S = Surface mass balance, M = Ice melt, Suffix g = grounded (upstream of the grounding line) and Suffix u = ungrounded (downstream of the grounding line)
Important point: what follows concerns the surroundings of the grounding line and is therefore not directly concerned by the melting away of the grounded line
Equations: Tg = Dg + Sg + Mg & Tu = Du + Su + Mu (The authors actually use elevation instead of thickness, which gives a slightly different formula in the case of the ice shelf: ungraunded)
Hypothesis: Dg ≈ Du, Sg ≈ Su and Mu ≈ 0, which results in Mu = Tu – Tg
Note from Sidd: in the case that Mg is not equivalent to zero then Mu = Tu - Tg + Mg and so the melt is even greater (the problem is that at the moment there is little knowledge of the term and its application in these cases)
Second point: the ice mass balance
Mass ice balance = Ice discharge (measured on the grounding line) + Surface mass balance + Water discharge (correspond, in our case, to the bed melting)
Note: The catastrophic ice mass balance is determined by the significant change in ice discharge, which is calculated by satellite measurements (elevation, velocity and position of the grounding line) and is not derived by calculation of the other elements!
Note: as the other elements are estimated any significant melting in the mass balance of the ice would have been detected, which was not the case

Third point: But a smaller and therefore non-detectable melt could have produced enough water to lubricate the bed.
The formation of sub-glacial lakes would have been detected (this is an area over which radar aircraft flights are more numerous) which was not the case

Fourth point: the explanation for the accelerated withdrawal of the grounding line
On the one hand, we have a theory that dates back to the 1970s, which was subsequently confirmed by models and verified and proven on many occasions in Antarctica as well as in Greenland.
It is a theory accepted and validated by the community of glaciologists.
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West Antarctica is full of volcanoes and for example there has historically been a sub-glacial eruption in the PIG (and of course it has been detected) and, still under the PIG there is geothermal heat (it is monitored from the presence of certain isotopes released in the melt water), so volcanism is important, but in the sense that "It never rains but it pours" or "that's done it" "we needed, another disgrace".

I advise you to start with Marine Ice Sheet Instability “For Dummies”, David Docquier June 22, 2016 (EGU Blogs) https://blogs.egu.eu/divisions/cr/2016/06/22/marine-ice-sheet-instability-for-dummies-2/

PS: perhaps others have other more useful references at hand and could kindly provide them to you
« Last Edit: February 15, 2022, 10:19:35 PM by oren »

oren

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Re: Crosson and Dotson Ice Shelves Discussion
« Reply #28 on: February 15, 2022, 10:25:36 PM »
Paolo, thanks for the detailed response and explanation (I removed one sentence). I think Steve is genuinely looking for such explanation, and we are getting a good discussion.
Steve, please follow up on Paolo's link, and if any confusion remains it is best to try to formulate it in the terminology given (or in another well defined terminology).