Humboldt Gletscher / Sermersuaq / North West Greenland

[Espen]

The largest known glacier of the Northern Hemisphere, is Humboldt Gletscher, named after the German naturalist Alexander von Humboldt.
Discovered by Elisha K. Kane on his expedition of 1853–55.

Strange enough, there is not much discussed about this "Natural Monster" but there is still something to be discovered, with the help of our Image Wizard etc. "Wipneus", I have noticed many large cracks behind the calving front of the glacier. (See attached image).

Please ! Click on image to enlarge!

[Anne]

I had to Google that.

[Espen]

Another image from Landsat and Wipneus:

Please ! Click on image to enlarge!

[Espen]

I had to Google that.

Compared to "much" smaller glaciers, everything is relative!

[Wipneus]

The glacier image looks distinctly different than others that we have been looking at.

Hope for a day with even clearer weather to image those features.

[Wipneus]

This Peterman image shows also the upper tongue of the Humboldt glacier in much better viewing conditions than the images above.

This 15m hi-res image seems to show that we have a giant iceberg factory here.

(click the picture, then enjoy)

[Espen]

Ban Ki-moon from the UN is as I write this text visiting Jakobshavn, he obviously wants first hand data of the situation.

[Espen]

Those ice cubes would be fine for a GT

[icefest]

Those ice cubes would be fine for a GT

That'll make the Gulf of St lawrence not the only thing getting sloshed about.

[Espen]

A massive calving is underway at Humboldt. This part of Humboldts calving front represents only a  fraction (30 km) of the total +/- 100 km.

Please click on the image to start the animation!

[Espen]

From today's IceBridge flight, the huge calving mentioned in the above animation is seen on the this image, courtesy of NASA:

More info here: https://forum.arctic-sea-ice.net/index.php/topic,779.msg25266.html#msg25266

[Espen]

Calving underway at Humboldt, the "piece" indicated with red arrows is aprox. 5 km x 1 km.

Please click on image to start animation!

[Espen]

Humboldt update:

Please click on image to start animation!

[Espen]

Humboldt update:

Please click on image to start animation!

[mspelto]

This glacier is not the largest in Northern Hemisphere, just has the widest calving face.  It also lacks deep water extending far beneath the glacier.  The crack noted I am not convinced is real-could be an artifact, if it is it appears to be a surficial stream not crevasse or rift. http://glacierchange.wordpress.com/2010/09/04/humboldt-glacier-retreat-greenland/

[Espen]

Calving at Humboldt, the piece we have been following went into several pieces, which is typical of Humboldt:

Please click on image to start animation!

[Espen]

Here is a reminder how much Humboldt Gletscher retreated in exactly 20 years, please note the total width of the image is 30 km and the height is 50 km.

One thing puzzling me analyzing the 2 images, the melt ponds are more or less places at the same spots, although the glacier is moving, how come?

Another important observation is the glacier is retreating more or less over the whole front, although far more in the north.   

Please click on the image to start animation!

[JayW]

Thanks for all your efforts Espen, I have enjoyed your posts for a long time and wanted to voice my appreciation.

The other day I was toggling between 2013 and 2014 and noticed that the melt ponds didn't seem to move, but being just one year apart, I didn't think any more about it, until seeing your wonderful post!.  It's remarkable how consistent they are, 20 years apart. It reminds me of the rivers features when whitewater rafting.  The waves, holes, hydraulics, eddies, etc..., are always in the same spot, and are caused by the shape, and features of the river bed. Just a thought.

I also noticed when toggling between consecutive days, some ponds seem to disappear overnight, often in clusters. Only to reappear again. 

[Espen]

JayW,

Thanks, yes it a bit of a mystery what makes these melt ponds so stationary, but as your observations with rivers, river/water and glacier/ice is very similar in behavior, so these melt ponds must have a relation with the bedrock somehow?

[mspelto]

Supraglacial lakes most often do reflect surface topographic lows that are generated by the topography of the glacier bed, there is a distance lag that depends on thickness and velocity.  So the bedrock feature is not immediately below the surface expression.  In the case of melt ponds they can also be self-reinforcing by accentuating melt, this is the case where surface velocity is quite low.  Most melt lakes do not drain rapidly, though that mechanism gets most of the press. 
 http://www.the-cryosphere.net/8/107/2014/tc-8-107-2014.html is one example that looks at this.

[Espen]

Supraglacial lakes most often do reflect surface topographic lows that are generated by the topography of the glacier bed, there is a distance lag that depends on thickness and velocity.  So the bedrock feature is not immediately below the surface expression.  In the case of melt ponds they can also be self-reinforcing by accentuating melt, this is the case where surface velocity is quite low.  Most melt lakes do not drain rapidly, though that mechanism gets most of the press. 
 http://www.the-cryosphere.net/8/107/2014/tc-8-107-2014.html is one example that looks at this.

Thanks Mauri,

But does that explain why the melt ponds sit at almost the same place during a 20 years period?

[icefest]

I think this was talked about in another  thread.

The link between bedrock disturbances size (wavelength) and the glaciers thickness and the effects on glacial surface topography.

Here it is: http://forum.arctic-sea-ice.net/index.php/topic,314.msg14672.html#msg14672

[Espen]

Another big calving at Humboldt (red encircled):

The width of animation below is 42,12 km.

Please click on image to start animation!

[Espen]

Here is a "spring" update on Humboldt, not much to report but please notice the impressive crevasse-highway between the 2 red lines:

[mspelto]

What I find impressive is the lack of movement of the icebergs between the two, indicating the first was near freezeup.

[Seumas]

Clear skies give a pretty picture on Worldview today:

[Espen]

Signs of retreat at Humboldt Gletscher:

[Espen]

"40 years service" showing steady retreat of the grand Humboldt Gletscher:

Please click to enlarge and animate!

[georged]

"40 years service" showing steady retreat of the grand Humboldt Gletscher:

Please click to enlarge and animate!

What area would this cumulative loss represent?

[oren]

What area would this cumulative loss represent?

Pixel counting is the best method but with a quick eyeballing the animation, Humboldt's width at its calving front is about 100 km though I think the width shown here (top to bottom of the images) is about 60-80 km, and the lost area is probably some hundreds of km².

[Tor Bejnar]

A week before Christmas I read some entry in a blog (I thought it was in these threads, but I cannot find it, so it must have been somewhere else.) about a biography of Alexander von Humboldt - The Invention of Nature - by Andrea Wulf.  I bought it and just finished reading:  Wow!

As the author writes in the Epilogue,

Humboldt's disciples [including Charles Darwin, Henry David Thoreau, George Perkins Marsh, Ernst Haeckel and John Muir] and their disciples in turn, carried his legacy forward - quietly, subtly and sometimes unintentionally.  Environmentalists, ecologists and nature writers today remain firmly rooted in Humboldt's vision - although many have never heard of him.  Nonetheless, Humboldt is their founding father.

Contemporaries who were influenced by Humboldt (sometimes late in life) include Johann Wolfgang von Goethe, Simón Bolívar, Thomas Jefferson and Edgar Alan Poe.  Humbolt invented the word "cosmos"*, and was approximately the first explorer to describe ecological zones (mountain ecology mimics more northerly plains ecology).  He was a proponent of holistic thinking about science, including, for example, how we feel about a subject (these trees or those rocks or that parasitic plant), not just the object's physical characteristics (as if we were separate from it). 

Although pretty unknown in the modern English-speaking world, more place names around the world are named after him than anybody else, I read.  Today's German and Latin American school children are, however, likely to know who he was, I'm led to understand.
____
*  - 1st 3 of 8 references in Wikipedia for "Cosmos":

[sidd]

Re: Humboldt

I recommend the new English translation (I am incompetent in German) by Mark Person of "Views of Nature" published in 2014 by the University of Chicago Press. I have a translation of  "Essays on the Geography of Plants" awaiting my attention for many months now. Humboldt repays study, even today.

Also, I like saying "Humboldt." It reminds me of elephants somehow.
sidd

[wili]

Alex was cool. But don't forget his brilliant, older, stay-at-home, linguist brother Will!

https://en.wikipedia.org/wiki/Wilhelm_von_Humboldt

[prokaryotes]

Currently Open Access

Paleofluvial and subglacial channel networks beneath Humboldt Glacier, Greenland

We suggest that basal meltwater is actively
being routed down both the paleofluvial and subglacially formed channel networks to the coast.
Inheritance of the preglacial channel network may have influenced the present-day location
and dynamics of Humboldt Glacier and enhanced selective erosion at its down-glacier end.

http://geology.gsapubs.org/content/early/2017/03/27/G38860.1.full.pdf+html

[Espen]

Humboldt Gletscher update: The glaciers northern part is seen retreating:

[Alphabet Hotel]

Humboldt has calved

[Tor Bejnar]

I don't see it.  Attached:  Sentinel images from DMI July 1 and July 25.  Fast ice has clearly broken off.  The blue line once traced the front, but it has calved since then.  One can pretty clearly follow the front on the July 25 image (contrast with remaining fast ice is mostly very obvious) and compare point to point on the July 1 image. 

Was the calving you refer to before July 1?  (Or maybe my eyes are going blind  )
[click to see GIF]

Edit:  I was shown a minor (very minor) calving between the 10th and 25th near the northern end of the front (~79º 47' N).  I can see the fracture on the 10th image.

[Alphabet Hotel]

July 26, looks a small calving and/or melt water release. Some kind of wave is spreading away from the point of release.

[oren]

The gif in the previous post also hinted at massive meltwater release. The whole fast ice was suddenly pushed away.

[Tor Bejnar]

Cross-post:

Calving in Kane basin as we speak.

GIF of Humboldt Glacier calving at link or in the original post.
https://forum.arctic-sea-ice.net/index.php?action=dlattach;topic=176.0;attach=129334

[blumenkraft]

From 01.06 with ~15 days increments. Last frame yesterday.

A rather big file, so click to play.

[DrTskoul]

And iceberg slide...

[gerontocrat]

From 01.06 with ~15 days increments. Last frame yesterday.

A rather big file, so click to play.

Stunning images, but ......

Too damn fast for my tired old eyes! Can't see where the bits are falling off! I make my gifs very slow to start, slow to play, and even slower on the last frame (if it is repeating itself). I am no longer an impatient youth (not that I was really ever into the "hit the ground running" crap).

Your eyes will get old and slow one day.

[blumenkraft]

Your eyes will get old and slow one day.

No doubt about that.

Thanks for the feedback, i will keep that in mind.

[BenB]

I'm not yet (that) old, but I agree with Gero that in general people on ASIF create GIFs that are too fast. You end up having to watch them lots of times, and still don't get as clear an understanding of what's going on as you would if they were slower. Also support having the last frame slow/long, so that if the GIF is looping, it's clear what the final state is, and when the GIF starts/ends.

[blumenkraft]

Moah minor calvings. This is 14th vs. 15th.

Is this GIF playing slow enough for you guys or still too fast?

[oren]

The GIF plays fine but I fail to see the calving this time...

[DrTskoul]

Circles upper side of gif

[oren]

Nice, thanks BL and DrT.

[blumenkraft]

Circles upper side of gif

Yeah, but also below:

Note how that iceberg is pushed into the basin and leaves a trail of crushed ice behind it.

BTW if you see this bright blue crushed ice somewhere, this is a sign for a calving. There is always a lot of debris produced by a calving, not only icebergs.