Animation 8: Kangerdlugssuaq Glacier

Hold on, let me check if I spelled that right. K-A-N-G-E-R-D-L-U-G-S-S-U-A-Q. Okay, all clear.

I received a comment from Werther in the blog post on Jakobshavn Isbræ pointing me towards another Greenland glacier called Kangerdlugssuaq. On the MODIS satellite images he noticed a strange blue swath showing up behind the glacier terminus. Happy as I was to have heard of a new Greenland glacier (and there are so many more), I decided to make a short animation before offering more information on this glacier.

The animation starts with an image of the situation last year, with a round marker to show where the terminus is located. The next images are from the last three days. What can be seen is that there has been a small terminus retreat compared to 2009 and on the last image we see the large blue swath.

 

After having looked attentively at the animation I conclude that the blue swath must be some sort of artefact, if only for the fact that it is physically impossible for a melt pond or glacial lake of that size to form within 24 hours. Besides, it occurs right at the edge where two satellite images have been stitched together and you can see some of the dark patches right through it. Unless it rained very heavily for 20 hours, I think it's either a glitch or the shadow of a cloud.

So, this probably doesn't mean much, but it gives us the opportunity to learn some more about the Kangerdlugssuaq Glacier. Here's a picture of Greenland I found on ScienceDaily that shows the location of the glacier:

 

According to the very short Wikipedia entry Kangerdlugssuaq is the largest glacier on the east coast of the Greenland ice sheet. Another short piece of information on the Not So Green blog tells us that the Kangerdlugssuaq fjord stretches over 40 miles long, and is over six miles wide at its widest point. It is fed by at least 16 different glaciers, and therefore often contains large quantities of ice, as can be seen in this photo by Fluffy Dragon, especially in the high-resolution version.

It had people worried a few years back because of a spectacular increase in flow rate and mass loss. According to this BBC News article from December 8th 2005:

Kangerdlugssuaq Glacier on the east coast of Greenland has been clocked using GPS equipment and satellites to be flowing at a rate of 14km per year. It is also losing mass extremely fast, with its front end retreating 5km back up its fjord this year alone. The glacier "drains" about 4% of the ice sheet, dumping tens of cubic km of fresh water in the North Atlantic.

The same in this IPS news article:

After 40 years of stability, the Kangerdlugssuaq Glacier in southeastern Greenland has become one of the world's fastest-melting glaciers, says glaciologist Gordon Hamilton from the University of Maine. Hamilton took the first-ever direct measurements on the surface of Kangerdlugssuaq Glacier Jul. 18 and discovered it is now moving at an unglacial 38 metres per day, or 14 kilometres per year. That is nearly three times faster than it was in 2002 when a NASA plane flew over to take measurements.

Since 2005, however, the flow rate has slowed down again. This 2007 article from ScienceDaily is very explanatory:

Last week's Science Express article adds details from Greenland's second and third largest glaciers, Kangerdlugssuaq and Helheim, in the southwest part of Greenland. The two are known as "outlet" glaciers because their front edges reach all the way to the sea, unlike other glaciers that are landlocked. Together the two glaciers represent 35 percent of East Greenland's total discharge. The scientists examined the glaciers' speed, geometry and discharge between 2000 and 2006.

At Kangerdlugssuaq, roughly 80 percent of the total increase in discharge occurred in less than one year in 2005, followed by a 25 percent drop the following years, the authors say. At Helheim, discharge increased between 2000 and 2003, and then by an even greater amount between 2004 and 2005. It then dropped in 2006 to its near 2000 value.

The scientists say what they've learned is that the shape of these two glaciers changed as they surged toward the sea, changes that put the brakes on. The glaciers lost ice as their front edges began calving, became lighter and floated off the bottom, which led to more ice breaking off as the ice was buoyed up by water. The fronts stablized once the ice had retreated to shallower parts of the fjords and again rested on the bottom.

They also found the pace toward the sea was faster at the front edge of the glaciers than farther up the mountain. For example Kangerdlugssuaq's front edge increased in speed by 80 in 2005 percent while 19 miles inland the speed increased 20 percent. This caused the glaciers to thin, stretch and weigh less overall, which also slowed them down.

"All this in a matter of a few short years for these two glaciers is not the way glaciologists are used to thinking," Howat says. "We're used to thinking of the ice sheets in terms of millennia or centuries."

Here's a picture showing retreat up till 2007. Unfortunately I haven't been able to find more recent images, but I will as soon as I do. 

To top this blog post off I've uploaded a video from the homepage of Jason Box, a climatologist with the Byrd Polar Research Center, showing some amazing views of Kangerdlugssuaq Glacier, with background music by Pink Floyd which should please most of us greenie treehuggers:

According to the Byrd Polar Research Center blog Kangerdlugssuaq Glacier lost 5.2 square km in 2009.

Comments

[Glacierchange.wordpress.com]

The blue swath is not so much an artefact as a simply a differently color-contrast to this image. It is worth noting that all you have do is change the name and the story for the largest glacier draining east and west Greenland (Jakobshavn) are the same 40 years of stability, rapid acceleration and retreat. The Kangerdlugssuaq has been the focus of autosub work which was not entirely successful. The Kangerdlugssuaq does not have an extensive an inland penetration of high velocities noted by Joughin et al., (2010) figure 9as the Jakobshavn.

[Glacierchange.wordpress.com]

Forgot that the most telling point is the higher snowline in 2010 then 2009. This is the same as we see on Petermann and Jakobshavn bottom image, so the higher snowline in mid-summer is wide spread.

[Neven]

The snowline is indeed telling. I hadn't noticed it yet. Thanks, Mauri.

[logicman]

Nicely spotted! I missed this one entirely.

The blue blob is a cloud shadow. You may want to check out this false color mosaic segment which shows the cloud and its shadow:
http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=Arctic_r02c02.2010201.terra.367.250m

Great post!

[Neven]

Thanks, Patrick. Perhaps Werther can enlighten us on how the h*ll he spotted that blue swath. On the other hand, it helps if you know that a big glacier exists there. I know now.

[logicman]

"it helps if you know that a big glacier exists there"

Big glaciers? In Greenland? You're joshing me, right? :-)

btw, watch the two former tributaries for retreat. Previously they were held up by the back-pressure from the main stream. Now that there is no back pressure on the tributaries you effectively have 3 glaciers and 3 calving fronts where there was one. And of course, the main stream is free of the back-pressure of the tributaries. Watch out for some acceleration.

[Bob Smith]

NSIDC has an update

[Peter2010]

The mysterious NOAA Cam 2 temperature variation solved..

As this got myself and couple others curiosity going a couple of days back, so i thought i'd revisit it as my speculative 'its the ice melting off the enclosure' didn't seem right. So i did a little delving and this is what I've discovered..

- Every 6 hours, Cam_2 takes a set of up to 6 images. (speculate that some images drop via comm. loss)
- a 2 to 3 minute separation between each image capture in the set.
- Internal Temp start at ~4.5C and typically ends the last shot at ~12c

The reason for the ~8c temp variation is very likely due to the camera flash, causing an increase of about 2c per shot.
The additional heat is then lost within 6 hours, and starts the next cycle again at 4.5c internal temp.

Shot Cycles taken at (+/- 10 minutes)
01:0X
07:0X
13:0X
19:0X

Why is this of interest? resolve confusion on interpreting internal cam temperature.
The temperature variation may affect the image quality or colour (can anyone confirm this?)

http://www.arctic.noaa.gov/npole/index.php
http://www.arctic.noaa.gov/npole/2010/images/noaa2-2010-0719-070708.jpg
http://www.arctic.noaa.gov/npole/2010/images/noaa2-2010-0719-071708.jpg

[Peter Ellis]

Can a flash really heat the camera by a whole 2 degrees? I'd be more inclined to suspect that there's a heater in there to get rid of condensation, rime etc. - hence also the reason for taking several exposures to make sure at least one comes out.

[Peter2010]

Peter, I did consider a heater, but things start getting complicated, eg a far bit of additional power needed, larger enclosure enclosure, deviating from the KISS model - lots more things that could go wrong. But in a sealed, insulated container (think deep space probe), a cam flash would give off additional heat.

checking NOAAA site again and "The instruments typically continue to transmit data for months after the solar-powered web cams stop"..

solar power heater in frigate NP, its improbably but not impossible.

[logicman]

From the horse's mouth: "This system used large solar panel arrays, blowers and heaters to keep the lenses clear."
http://www.oceantronics.net/NOAA.htm

Also note that when the sun shines and charges the batteries - they warm up.

hth :-)

[Peter2010]

thanks for that link logicman.. prompted me to delve a bit further into the background on these cam...
i believe the 'heaters and blowers' are to keep the solar panels clear, as for the Cam "NOAA is keeping the device turned off except for just ten minutes every six hours, in order to conserve its solar-charged battery power".
Also, If you look at the CAM specs, there is no need for a heater for it to function well.

# Operating temperature: -40 to +48 deg. C
# Power requirements: 7.2VDC-10VDC, 1A, 9VDC power supply included
# fully isolated relay or photo flash trigger, rated at 28VDC 2A or 125VDC 0.5A
# 5VDC 50mA regulated power supply

http://thing1.linuxdevices.com/articles/AT4739871225.html
http://www.noaanews.noaa.gov/stories/s898.htm

The images will track the North Pole snow cover, weather conditions, and the status of NOAA's Pacific Marine Environmental Laboratory's North Pole instrumentation, according to James Overland, head of NOAA's North Pole Project. Although the webcam is capable of transmitting camera video at the rate of an image per second, NOAA is keeping the device turned off except for just ten minutes every six hours, in order to conserve its solar-charged battery power. Four times a day, the webcam wakes itself up and places a phone call to NOAA so that its data can be collected (the data is transferred by 2400 baud modem, through the Iridium low earth orbit satellite system, using PPP).

The webcam contains a temperature sensor, allowing the temperature of its local environment to be monitored -- note the temperature reading in the lower left-hand corner of the above photo (Click here for an enlarged photo). Various configuration parameters -- including zoom, frequency of photos, and other camera settings -- can be remotely configured via web access.

[Kevin McKinney]

Now, if only we knew what happened to webcam 1. It's now 2 weeks & counting since the picture updated.

The temps from the cam 1 location are weird, too--they suddenly dropped 12C yesterday at 1300, stayed there, more or less, for about 16 hours, then rebounded to a fairly normal
-2.1C. I for one am really curious about this. . .

[Kevin McKinney]

Prelim melt is about 60K today. Back to the mean or thereabouts. . .

[Werther]

Hi Neven… my short lived worry/excitement on the blue swath on K.glacier. It appeared on the mosaic 20/7. The melting season gets me looking for change for the last 4 years (creating more social then actual icesheet-worries). Since I got to MODIS a ‘quick scan’ around Greenland is easier then ever.
Though I like maps since I was a child, I’m still easily tricked. The Terra-version showed me later that it was blueish shadow of an oval cloud over the nunatakker to the southwest. Still a strange feature, but not a meltpond out of a suddenly opened ‘moulin-channel’ (that would really be something).
Why the interest? Discussion 4 years ago at the presentation of KNMI regional climate models/sea level rise. I wonder what a still small rise like 15 cm/10 years would do to fragile coastlines. An amateur calculation shows that mean retreat of some 4 kilometers around the G. icesheet would produce something like that. Of course in steps in a geometrical array, beginning at a melt rate of 250 cubic km going up to 1500/y, some 4000 ckm after 10 years.
This year up to now is the warmest ever, Greenland is surrounded by +2-+5 SST anomalies… NASA SLC is now +3,26 mm/y..is it happening? as Anu wrote ‘Science is interesting, but slowwwwww’. Anyone willing to check the math? You may be interested in: Greenland ice sheet surface temperature, melt and mass loss:
2000–06 / Journal of Glaciology, Vol. 54, No. 184, 2008

[dorlomin]

Would a change in the thickness and strength of the arctic sea ice to the North of Greenland affect the speed of outflow of the glaciers up there? I am thinking a bit like the ice shelfs in the Antarctic.

[Nick Barnes]

:dorlomin: No, not much. Ice shelves in the antarctic are hundreds or thousands of metres thick. The arctic sea ice is only a few metres at most.
There is, of course, an albedo effect: sea not covered by ice will be warmer, which can have an effect on the adjacent land ice. Also weather effects: waves and tides are greater, precipitation patterns change, and so on. All of that can affect land ice.

[Neven]

Werther, thanks for the comment and thanks again for pointing out the blue swath. The same happened to me a while ago when looking at Jakobshavn right after the north side of the glacier retreated. A weird looking shadow made me go haywire thinking that perhaps a huge part of the ice sheet surrounding the glacier had collapsed. I guess it's part of glacier initiation rituals. ;-)