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Author Topic: Nunatakassap Sermia / North West Greenland  (Read 20767 times)

Espen

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Nunatakassap Sermia / North West Greenland
« on: September 05, 2015, 12:10:08 PM »
Dramatic changes is seen at Nunatakassap Sermia, another grand but almost Google unknown glacier in Greenland, over the last 17 years since 1998 the glacier retreated some 15 km equal to +/- 70 km2 of ice area that is about 80 % the size of Manhattan, and probably + 100% of the volume even if all constructions in Manhattan were the size of One World Trade Center:

Notice the unnamed glacier to the north of Nunatakassap Sermia is trying to follow suit.

Note the 2nd frame in the animation should be August 27 2015 (not 1998)

Please click on the image to start animation
« Last Edit: September 05, 2015, 10:15:37 PM by Espen »
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #1 on: September 05, 2015, 12:21:23 PM »
The retreat is by no means over, this can easily be watched here:
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #2 on: September 05, 2015, 05:45:43 PM »
Size wise (width) Nunatakassap Sermia is very similar to Jakobshavn Isbræ (southern branch):
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #3 on: September 05, 2015, 09:07:38 PM »
The more I study Nunatakassap Sermia, the more impressed I become, this thing really shows muscles:
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oren

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Re: Nunatakassap Sermia / North West Greenland
« Reply #4 on: September 05, 2015, 10:22:42 PM »
Very impressive.
I keep wondering - JH and a few others are well known, this and many others are "under the radar" though the retreat is very significant. Is there somewhere a statistic of the total annual retreat of the whole of Greenland? Some scientific institution should take this up. This could be a very good tracker of the progress of AGW and of potential acceleration in GIS melt.

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Re: Nunatakassap Sermia / North West Greenland
« Reply #5 on: September 05, 2015, 10:31:29 PM »
My (I am not an expert) estimate is we really dont know?

Just the stupid discussion about the JH calving in July was the largest or not, tells it all. At least some of the "experts" dont know what they are talking about!


Very impressive.
I keep wondering - JH and a few others are well known, this and many others are "under the radar" though the retreat is very significant. Is there somewhere a statistic of the total annual retreat of the whole of Greenland? Some scientific institution should take this up. This could be a very good tracker of the progress of AGW and of potential acceleration in GIS melt.
« Last Edit: September 05, 2015, 10:48:20 PM by Espen »
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Re: Nunatakassap Sermia / North West Greenland
« Reply #6 on: September 06, 2015, 12:38:30 PM »
You are an expert, just a different expertise, and that is knowing from seeing the changes.  There are annual changes of GIS margins documented by various groups note Twila Moon-Joughin UW and Howat OSU group.  The annual shifts not that important overall, decadal shifts key and any dramatic irreversible changes of course.  For this glacier most of the change occurred by 2011.

http://blogs.agu.org/fromaglaciersperspective/2012/08/19/alison-gletscher-nw-greenland-rapid-retreat/

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Re: Nunatakassap Sermia / North West Greenland
« Reply #7 on: September 06, 2015, 01:22:54 PM »
Here is a GEUS map from the area:
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #8 on: September 06, 2015, 01:44:51 PM »
For this glacier most of the change occurred by 2011.

http://blogs.agu.org/fromaglaciersperspective/2012/08/19/alison-gletscher-nw-greenland-rapid-retreat/

I have to somehow disagree about the present status, below there is an animation showing Aug. 2012 vs Aug. 2015, the calving front was more or less in the same position in 2011 and 2012, but since then I think we have seen a considerably further retreat of the glacier, and it will probably change direction to the north east, due to not yet seen rock islands:
« Last Edit: September 06, 2015, 01:50:54 PM by Espen »
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oren

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Re: Nunatakassap Sermia / North West Greenland
« Reply #9 on: September 06, 2015, 03:59:37 PM »
Here is a GEUS map from the area:

According to the map there's been a significant retreat in the adjacent glacier (a bit to the north) as well.

Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #10 on: September 06, 2015, 04:51:15 PM »
Here is a GEUS map from the area:

According to the map there's been a significant retreat in the adjacent glacier (a bit to the north) as well.

Yes the map was made in the 90ties. Edit: 1985
« Last Edit: September 06, 2015, 09:18:01 PM by Espen »
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #11 on: September 07, 2015, 06:40:15 PM »
Remember I wrote this glacier was more or less "Google unknown", that is still true.
But there is a bit of confusion about the name of this glacier, some scientific reports claim the glacier is called Alison Gletscher, but according to all the material (Danish) I have trawled, no glacier is called that name in Greenland, how this name (Alison) came up is therefor a ?
However, there is a bay south of  Nunatakassap Sermia and Wandel Land called Alison Bugt so I guess Alison is easier to write/say than Nunatakassap Sermia even for sciencetists ;)

No wonder why folks in Greenland wants to change the place-names into the Greenlandic names.

« Last Edit: September 07, 2015, 06:47:15 PM by Espen »
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #12 on: September 07, 2015, 09:37:02 PM »
Some heavy calving at Nunatakassap Sermia between Sep. 4 and Sep. 7 2015:

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Re: Nunatakassap Sermia / North West Greenland
« Reply #13 on: September 07, 2015, 09:46:26 PM »
Hidden rocks at Nunatakassap Sermia:
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Re: Nunatakassap Sermia / North West Greenland
« Reply #14 on: September 14, 2015, 11:01:03 PM »
More calving seen at Nunatakassap Sermia, and record retreat between Aug. 27 2015 and Sep. 14 2015:

Remember this glacier almost have the same size (width) as the southern branch of Jakobshavn.
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Re: Nunatakassap Sermia / North West Greenland
« Reply #15 on: September 23, 2015, 10:39:11 PM »
Nunatakassap Sermia is preparing for another large calving:
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #16 on: September 23, 2015, 10:58:01 PM »
A High Resolution image from Sep. 23 2015 showing the same crack:
« Last Edit: September 23, 2015, 11:07:29 PM by Espen »
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Re: Nunatakassap Sermia / North West Greenland
« Reply #17 on: October 10, 2015, 10:44:33 AM »
Continuing calving activities at Nunatakassap Sermia:
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Re: Nunatakassap Sermia / North West Greenland
« Reply #18 on: October 10, 2015, 03:14:02 PM »
Quote
some scientific reports claim the glacier is called Alison Gletscher .. there is a bay south of Nunatakassap Sermia and Wandel Land called Alison Bugt  these names are more or less "Google unknown"

Sic transit gloria mundi: these valiant euro-explorers, instead of achieving immortality through place names, have dropped out of human memory already. 

I can confirm the 'google unknown' part -- could not find 'Alison' or 'Wandel' for whom the big nunatak south of Espen's glacier is named. The spelling 'Nunatakassap' itself is questionable: nunataq is Greenlandic, assap is not found in the most extensive dictionary. The native people do not seem to name things after valiant villagers, I suppose because everyone had to be valiant in the old days just to be there.

http://2010.polarhusky.com/media/cms/investigate/StudyResources/EnglishKalaallisutDictionary.pdf

Kiatassuaq Island (aka Holm Ø) probably refers to Gustav Frederik Holm (1849-1940), an explorer of East Greenland. Melville Bay is presumably named after Admiral George Wallace Melville, an Arctic Ocean explorer who did not visit this area.

Overall, I suspect none of the above ever set foot on Nunatakassap Sermia. Natives would be unmotivated to visit as there is no hunting to be had here or farther inland. It's possible that crevasse-free  upper reaches have been crossed by dog sled to bypass Melville Bay. But that too makes little sense. Peary did however make some remarkable treks of this type farther north.

In terms of sea level rise significance, Nunatakassap Sermia would have to jump out on velocity maps of inland Greenland. These, as well as velocity change maps, are robotically generated and so unbiased, nothing could be overlooked (in theory). My understanding is that a 2015 update for all of Greenland has been completed by Scambos et al but not yet published. So Nunatakassap is something to keep an eye on when that does appear.

In terms of glaciers 'waking up' ahead of schedule, if a schedule even exists it so conservative that surprises are baked in. Just like those trees falling in the forest, if no one is monitoring, surprises go unnoticed for years. Thus surprises aren't really surprising. Are you surprised at this?

On the Antarctic side, despite it being constantly in the news, less than a dozen humans have ever set foot on Thwaites Glacier as of 2015. Remote areas are very expensive to visit and logistically problematic if safety is a consideration.
« Last Edit: October 10, 2015, 03:42:38 PM by A-Team »

Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #19 on: October 10, 2015, 03:51:39 PM »
I can recall a few variations of the name Nunatakassap Sermia, but cant find them at the moment, but that said there can be different spelling due to dialects.
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Re: Nunatakassap Sermia / North West Greenland
« Reply #20 on: October 10, 2015, 06:14:29 PM »
Here is another image showing a large piece of glacier ice ready to be shipped:
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Re: Nunatakassap Sermia / North West Greenland
« Reply #21 on: October 10, 2015, 09:26:00 PM »
We can put this forum into hibernation pretty soon?

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Re: Nunatakassap Sermia / North West Greenland
« Reply #22 on: October 10, 2015, 10:14:07 PM »
Quote
some scientific reports claim the glacier is called Alison Gletscher .. there is a bay south of Nunatakassap Sermia and Wandel Land called Alison Bugt  these names are more or less "Google unknown"


In terms of sea level rise significance, Nunatakassap Sermia would have to jump out on velocity maps of inland Greenland. These, as well as velocity change maps, are robotically generated and so unbiased, nothing could be overlooked (in theory). My understanding is that a 2015 update for all of Greenland has been completed by Scambos et al but not yet published. So Nunatakassap is something to keep an eye on when that does appear.



They then have to rewrite a lot of papers, because Alison is not there?

Who the f... is Alison? (Smokie)
« Last Edit: October 10, 2015, 10:35:39 PM by Espen »
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Re: Nunatakassap Sermia / North West Greenland
« Reply #23 on: October 11, 2015, 10:53:58 AM »
We can put this forum into hibernation pretty soon?
S-1 IW of Greenland-margin is acquired every 12 days throughout the winter, so no need for that.

« Last Edit: October 11, 2015, 11:01:11 AM by nukefix »

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Re: Nunatakassap Sermia / North West Greenland
« Reply #24 on: October 11, 2015, 12:51:54 PM »
As suggested above we have a large calving at Nunatakassap Sermia must have happened between Oct. 9 and Oct. 10 2015:

(A-Team: it is not over until the fat lady sings!)
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Re: Nunatakassap Sermia / North West Greenland
« Reply #25 on: October 11, 2015, 01:02:32 PM »
Here is what Nunatakassap Sermia calved (red line)

Aprox. 4 km2 And a new record retreat position.
« Last Edit: October 11, 2015, 01:08:57 PM by Espen »
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Re: Nunatakassap Sermia / North West Greenland
« Reply #26 on: October 11, 2015, 02:20:18 PM »
Quote
We can put this forum into hibernation pretty soon?
S-1 IW of Greenland-margin is acquired every 12 days throughout the winter, so no need for that.
 large calving at Nunatakassap Sermia must have happened between Oct. 9-10. opera is not over until the fat lady sings
Petermann was -20ºC already in mid-September. Meltwater lubrication? The glacier will keep creeping down the hill all winter at reduced speed but I don't expect the ice shelf to be doing any rifting until mid-May.

And so it will go, a bit delayed, at each lower latitudesas per conventional wisdom. Actualy there has been little by way of observation so I welcome the regularly spaced IWs of cycle 62, especially after the hit-or-miss nature of cloud-free Landsats.

See you guys down at Thwaites?

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Re: Nunatakassap Sermia / North West Greenland
« Reply #27 on: October 11, 2015, 03:48:19 PM »


See you guys down at Thwaites?

I will stay north, and follow you from a "distance".
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Re: Nunatakassap Sermia / North West Greenland
« Reply #28 on: October 18, 2015, 04:36:14 PM »
Another large calving happened between Oct.9 and Oct. 14 2015, meaning Nunatakassap Sermia now reached another record retreat position, one of many this season by the way:
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Re: Nunatakassap Sermia / North West Greenland
« Reply #29 on: October 18, 2015, 05:58:12 PM »
Here is a high resolution animation of the calving between Oct. 9 and Oct. 14 2015:

Click on image to animate!
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Re: Nunatakassap Sermia / North West Greenland
« Reply #30 on: November 01, 2015, 05:48:55 PM »
More "Dark Season" calving seen at Nunatakassap Sermia, the glacier is now heading in a more northerly retreat direction (new record retreat position):
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Re: Nunatakassap Sermia / North West Greenland
« Reply #31 on: December 09, 2015, 09:23:41 PM »
Winter, what winter?
Nunatakassap Sermia is grinding its way into the interior of Greenland
(Notice her cousin in the north is active too):
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Re: Nunatakassap Sermia / North West Greenland
« Reply #32 on: December 09, 2015, 10:27:34 PM »
Amazing.

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Re: Nunatakassap Sermia / North West Greenland
« Reply #33 on: December 12, 2015, 06:42:30 PM »
Quote
this glacier was more or less "Google unknown", that is still true.
There are a fair number of papers on Alison Glacier using Google Scholar. Most of them are part of broader studies of velocity changes of all west-central Greenland glaciers and efforts to characterize ocean water circulation at calving fronts but there's even been seismic event attributions to Alison.

However I couldn't find any indication that anyone has ever set foot on the glacier itself despite the surge in tourism. Thus there has been no steam drilling much less ice cores. This means internal ice temperatures and geothermal flux are just guesswork.

The radar tracks are far and few between and it's hard to imagine anything useful about the bedrock profile emerging from isotropic kriging. However AGU2015 abstracts suggest western Greenland is being re-kriged anisotropically (ie interpolation weighted by direction of flow) and channel bathymetry will finally get done.

You could be on to something with winter calving and imminent acceleration of discharge. Alison Glacier is most commonly compared to Jakobshavn, mostly because of loss of its floating ice shelf and switch to non-tabular calving.

To nail this down, newly determined Sentinel velocities could be compared with those of the past dozen or so years.

http://onlinelibrary.wiley.com/doi/10.1002/jgrf.20088/full
http://onlinelibrary.wiley.com/doi/10.1029/2010JF001757/full
http://onlinelibrary.wiley.com/doi/10.1029/2011JF002132/abstract
http://onlinelibrary.wiley.com/doi/10.1029/2012JF002412/full
http://onlinelibrary.wiley.com/store/10.1002/jgrf.20088/asset/jgrf20088.pdf?v=1&t=ii35n7j1&s=f34bb1c6386395d7fab4df2255b59857fdfc7869
« Last Edit: December 12, 2015, 06:49:31 PM by A-Team »

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Re: Nunatakassap Sermia / North West Greenland
« Reply #34 on: December 12, 2015, 07:02:20 PM »
Here are the interferometric velocities in this area. The original image wasn't copiously annotated and the color scheme has been used many times before; it likely represents a determination from March 2015 Sentinel data. Even with an enlarged image, it is not entirely clear which glacier is Alison but probably the central one with the purple (fast) at the calving front.

If so, this provides a convenient baseline from which future acceleration might be measured (if the underlying numeric data could be located).

It would also be worthwhile to animate the band 8 Landsats from the 2015 season to compare with earlier years. I have not yet tried bulk download of cloud-free band 8s from the Amazon AWS server but it would save a lot of time and gigabytes vs EarthExplorer.

More simply, just find a similar August date for 2013, 2014, and 2015 Landsat-8 and set them as a 15 m RGB. This will detect a significant change in velocity if there has been one.

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Re: Nunatakassap Sermia / North West Greenland
« Reply #35 on: December 12, 2015, 08:31:47 PM »
Using the name Alison Glacier, in Science papers, should definitely ring a bell? If I am not wrong!

But I am not a scientist!
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Re: Nunatakassap Sermia / North West Greenland
« Reply #36 on: December 12, 2015, 08:35:14 PM »
Using the name Alison Glacier, in Science papers, should definitely ring a bell? If I am not wrong!

But I am not a scientist, that may explain it(?)!

Much better a researcher?

(and fine without all the paper work)

« Last Edit: December 12, 2015, 10:25:24 PM by Espen »
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Re: Nunatakassap Sermia / North West Greenland
« Reply #37 on: December 12, 2015, 11:13:39 PM »
Quote
i'm a researcher who does fine without all the paper work.
Yes, yes we've heard all that before from Pink Floyd. It is picture work though that is needed in #33-#34, perhaps an honorary D.Sc. in it for you?

E Rignot made some very significant findings last season about the real bathymetry of these West Greenland fjords and calving fronts on marine terminating glaciers using sonar on a volunteered small vessel. Oceans Melting Greenland was supposed to follow up on that over the next four years but now it looks like another group has made inroads on that just using existing data.

It seems to me, given several fjords with both types of data, very substantial improvements in AirGrav data interpretation should be possible over all of Greenland using guidance from the much higher resolution sonar instances, in the sense of supervised classification.

Quote
Resolving bathymetry from airborne gravity along Greenland fjords
A Boghosian et al 02 Dec 2015
http://onlinelibrary.wiley.com/doi/10.1002/2015JB012129/full paywalled
http://tinyurl.com/opk4odn and http://tinyurl.com/o8psrvm free supplemental figures

Recent glacier mass loss in Greenland has been attributed to encroaching warming waters, but knowledge of fjord bathymetry is required to investigate this mechanism. The bathymetry in many Greenland fjords is unmapped and difficult to measure. From 2010 to 2012, National Aeronautics and Space Administration's Operation IceBridge collected a unique set of airborne gravity, magnetic, radar, and lidar data along the major outlet glaciers and fjords in Greenland. We applied a consistent technique using the IceBridge gravity data to create 90 bathymetric profiles along 54 Greenland fjords.
We also used this technique to recover sub-ice topography where warm or crevassed ice prevents the radar system from imaging the bed. We present the new bathymetry data and discuss observations in six major regions of Greenland covered by IceBridge. The gravity models provide a total of 1950 line kilometers of bathymetry, 875 line kilometers of subice topography, and 12 new grounding line depths.
« Last Edit: December 12, 2015, 11:25:47 PM by A-Team »

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Re: Nunatakassap Sermia / North West Greenland
« Reply #38 on: December 13, 2015, 04:26:32 PM »
At Nunatakassap Sermia, we might document surprising calving from overhead satellites and even measure acceleration but to get at an explanation (and predict future behavior) we need improved Melville Bay bathymetry as well as better bedrock mapping under the glacier (which gives ice thickness).

As mentioned, E Rignot made some very significant findings last season about the actual bathymetry of a few West Greenland fjords and calving fronts of marine terminating glaciers using sonar on a volunteered small vessel. OMG (Oceans Melting Greenland) will follow up on that over the next four years but now it appears part of that agenda has been achieved by Boghosian 2015 using existing data.

The primary interest in better bathymetry is not improved nautical charts but rather the accessibility of deeper (here warmer) ocean waters to the calving front. Because of poor vertical mixing, deeper waters of greater density can't get pass obstructing sills. These barriers might be old underwater terminal moraines at the far end of previous glacier over-deepenings or just less erosive bedrock.

On the other hand, a larger glacier during the last ice age might have gouged unobstructed channels that provide a direct connection of the calving front to waters circulating in Baffin Bay.

That's what it's all about: distinguishing channels from sills and potholes. It's far safer and faster to get the necessary data from an airplane than a small boat dodging icebergs calving from an active front. In fact, the data has already been gathered over the years by Operation IceBridge. However it's not as precise as a half-million dollar sonar hanging off the side of an on-site ship.

Realistically, western Greenland has far too many glaciers with short melange-free seasonal windows to comprehensibly map bathymetry with sonar. However the ones that have been mapped just north of Jakobshavn show that previous depth maps were wholly unsatisfactory for modeling future calving rates, indeed downright misleading to the extent the current paradigm -- control of glacier advance by frontal turbulence at basal meltwater exits -- is valid.

Given several fjords with both types of data, very substantial improvements in AirGrav data interpretation might be possible over all of coastal Greenland using guidance from the much higher resolution sonar instances, in the sense of learning where and why AirGrav goes astray and how best to interpolate from its initial limited resolution.

Data is only collected along a sparse grid of intersecting flight lines; 'ordinary kriging' is used to fill in the blanks. This method is isotropic: all compass directions are on the same footing. We've seen before at Petermann that's untrue: basal ice upheavals follow contemporary surface flowlines and multiple paleo bedrock channels drain ancient gradients. Indeed all Greenland's ice flows away from the central ridge with implications for physics-based interpolation.

Here we have a natural symmetry-breaking vector supplied by the direction of glacier travel (and thus maximal erosion). Thinking now of classical U-shaped glacial valleys, this polarization vector also provides a twofold axis of transect symmetry to the channel going to the sea.

Incorporating the dominant physical process into interpolation cannot help but improve outcomes. Here we have something simple and specific sitting within the larger topic of 'anisotropic kriging' which could involve tensorial (simultaneous multi-linear directional) influences.

While applying this to Nunatakassap (aka Alison Glacier) is certainly within the collective technical competency of this forum, it's better to first take a detour to Store Glacier and its neighbors as these were studied by both Rignot and Boghosian groups. This can provides insights into improvements in AirGrav inversion and a validation area for resolution interpolation proposals.

Indeed ImageJ --> Plugins --> Integral Image Filters --> Normalize Local Contrast provides a low-budget variable anisotropic interpolation for geolocated grayscale data, which here is conveniently aligned east-west to begin with.

We've long needed a separate forum for the Uummannaq region. The Store glacier there is being intensively studied in the SAFIRE project -- four instrumented holes being drilled to bedrock to get at mechanical and hydrological conditions at the base. Store Gletscher (big glacier in Danish) drains 35,000 km2 at 20 m per day by the calving front -- it's similar to but more favorable experimentally than Jakobshavn.

http://www.spri.cam.ac.uk/research/projects/safire/
« Last Edit: December 13, 2015, 04:41:39 PM by A-Team »

Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #39 on: December 18, 2015, 10:12:04 PM »
Nunatakassap Sermia, still action to be seen, though in a present gaining mode:

Click on image to animate:
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Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #40 on: December 19, 2015, 08:59:49 PM »
Here is the animation from above in a smaller version:
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Tor Bejnar

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Re: Nunatakassap Sermia / North West Greenland
« Reply #41 on: December 19, 2015, 09:11:06 PM »
Thanks, Espen!
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Re: Nunatakassap Sermia / North West Greenland
« Reply #42 on: December 19, 2015, 11:28:15 PM »
Right, #39 only has one frame so it plays real slow.

The more ambitious question, and hopefully one Espen can resolve this over next ten days or so while the rest of us are on solstice holidays, is whether the surprising activity at Nunatakassap Sermia is anomalous or part of a broader simultaneous Melville Bay debacle (as everything there might be affected by the warm currents accentuated along this part of the coast).

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Re: Nunatakassap Sermia / North West Greenland
« Reply #43 on: December 20, 2015, 02:30:43 PM »
While the glacier is advancing, there is some fairly significant calving on the southern portion of the calving face.

Espen

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Re: Nunatakassap Sermia / North West Greenland
« Reply #44 on: December 22, 2015, 10:30:28 PM »
Right, #39 only has one frame so it plays real slow.

The more ambitious question, and hopefully one Espen can resolve this over next ten days or so while the rest of us are on solstice holidays, is whether the surprising activity at Nunatakassap Sermia is anomalous or part of a broader simultaneous Melville Bay debacle (as everything there might be affected by the warm currents accentuated along this part of the coast).

My preliminary findings are: I dont think it is sea related, although the sea got an impact, but I think something inside the island of Greenland "tipped the boat" so to speak, what that is I am still unsure about, but if it was sea related we would not see glaciers all around the "island" being being pushed into the sea (calvings/retreats), we have Upernavik, Giesecke, Nunatakassap Sermia, Kjer Gletscher, Steenstrup, Sverdrup, Petermann, Steensby, Ostenfeldt, Hagen, Zachariae, Helheim. Midtgård and the one near the airport : Jakobshavn.
But still I think sea ice is just the fuse, the bomb is inside Greenland!
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Re: Nunatakassap Sermia / North West Greenland
« Reply #45 on: December 23, 2015, 05:21:04 AM »
I venture that decreasing surface mass balance is a clue, but i do not see clearly how.

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Re: Nunatakassap Sermia / North West Greenland
« Reply #46 on: December 23, 2015, 03:21:33 PM »
Right, #39 only has one frame so it plays real slow.

The more ambitious question, and hopefully one Espen can resolve this over next ten days or so while the rest of us are on solstice holidays, is whether the surprising activity at Nunatakassap Sermia is anomalous or part of a broader simultaneous Melville Bay debacle (as everything there might be affected by the warm currents accentuated along this part of the coast).

My preliminary findings are: I dont think it is sea related, although the sea got an impact, but I think something inside the island of Greenland "tipped the boat" so to speak, what that is I am still unsure about, but if it was sea related we would not see glaciers all around the "island" being being pushed into the sea (calvings/retreats), we have Upernavik, Giesecke, Nunatakassap Sermia, Kjer Gletscher, Steenstrup, Sverdrup, Petermann, Steensby, Ostenfeldt, Hagen, Zachariae, Helheim. Midtgård and the one near the airport : Jakobshavn.
But still I think sea ice is just the fuse, the bomb is inside Greenland!

I think it is increased surface melt...that water is diving into the core of the ice sheet. Some of it makes its way to the sea but most of it is causing a fundamental shift in the physics of the ice sheet.

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Re: Nunatakassap Sermia / North West Greenland
« Reply #47 on: July 26, 2019, 10:07:00 PM »
Big calving between the 24th and the 25th. Lots of liquid.
Click to animate.

Tor Bejnar

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Re: Nunatakassap Sermia / North West Greenland
« Reply #48 on: July 27, 2019, 07:00:43 PM »
Some of us just don't know Greenland geography like a local ...
Espen posted a GUES map of the glacier environment up-thread.  "But where in 'North West Greenland' is it?  Well the larger named island that looks like "Klalaussaq" is actually "Kiataussaq". Here is a screen print from the linked Wikipedia page.  (The map shows jurisdictional boundaries.)
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Re: Nunatakassap Sermia / North West Greenland
« Reply #49 on: August 17, 2019, 08:31:26 PM »
boom! (click to animate)

I believe this happened between the 15th and 16th of August. It's really impressive how far those icebergs out in the open water moved.