Why Southeast Greenland's glaciers have slown down since 2005

By: Dr. Jeff Masters , 3:57 PM GMT on December 15, 2009

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I'm in San Francisco for the annual meeting of the American Geophysical Union, the world's largest gathering of climate scientists. I saw ten or so great talks yesterday (and five really boring ones!) Here's a summary of the the most interesting talk I heard yesterday:

If you plan on owning ocean front property after the year 2050, you should pay close attention to the glaciers In Greenland. Greenland holds enough ice to raise global sea level by over 20 feet (6.5 meters), should its ice cap completely disintegrate--though such an event would likely take centuries to occur. Still, should the climate warm 2°C or more this century, partial melting of the Greenland Ice Sheet could readily raise global sea level by a meter or more by 2100. That's why scientists reacted with concern during 2003 - 2005, when all of the glaciers in southeastern Greenland accelerated in synchrony to speeds 30% to 210% faster than they had flowed in 1996. As they sped up, the glaciers began dumping huge amounts of ice into the ocean off the coast of southeast Greenland, more than doubling Greenland's contribution to global sea rise, to .57 mm/year. Would the glaciers keep accelerating, bringing about an increasing disintegration of the Greenland Ice Sheet? Nobody knew, since computer models of glacial dynamics were (and still are) in a primitive state.


Figure 1. Helheim Glacier in southeast Greenland, in three images captured in 2004, 2005, and 2006. The glacier accelerated significantly in 2005, and the face of the glacier retreated 5 km inland (middle frame) compared to 2004. However, by the summer of 2006, the acceleration ceased, the the glacier returned back to its 2004 position. Image credit: Ian Howat, University of Washington.

Well, it turned out that 2005 was the peak of the glacial acceleration event. The glaciers in southeast Greenland have returned to where they were eight or nine years ago--still causing a net loss of mass that is raising global sea level, but not as fast as in 2003 - 2005. In a talk titled, "Ocean regulation of glacier dynamics in south-east Greenland and implication for ice sheet mass changes", Tavi Murray and colleagues from the UK's Swansea University presented a plausible theory for why this strange synchronous speed-up and slow-down occurred. Using satellite, aircraft, and surface observations, the researchers found that air temperatures in the region did not vary much over 2003 - 2005 (Figure 2). Thus, a major increase in temperature could be ruled out as the cause of the glacier surge. However, study of the ocean temperatures near the coast revealed strong clues that ocean currents were responsible for the surge.

Figure 2. Ocean currents off the east coast of Greenland feature the cold East Greenland Coastal Current flowing north to south (white arrows) and the warm Irminger Current flowing south to north (red arrows). Image credit: Arctic Climate Impact Assessment.

Ordinarily, the southeast coast of Greenland features a cold water current flowing north to south, called the East Greenland Coastal Current (EGCC). Much of the cold water for this current is supplied by melting of the 14 glaciers in southeast Greenland that empty into the sea (two of these glaciers, Kangerdlugssuaq and Helheim, represent 35% of east Greenland's total glacial discharge). A few hundred kilometers offshore, a warm water current called the Irminger Current flows the opposite direction, bringing warm water from the North Atlantic northward. In 2003, it happened that weather conditions over Greenland brought an unusually low amount of run-off of precipitation. With little new mass pushing the glaciers seaward, the glaciers responded by greatly reducing the amount of ice they dumped into the ocean by the shore. As a result, the East Greenland Coastal Current slowed down and warmed, which allowed the warm Irminger Current to advance towards the coast, warming the coastal waters even more. All that warm water near the coast began melting the glaciers where they reached the sea, causing the glaciers all along the southeast coast of Greenland to accelerate and rapidly thin between 2003 - 2005. By 2006, the thinning glaciers had dumped so much new ice into the ocean near the coast that the waters cooled and the East Greenland Coastal Current re-established itself. This cooled the glaciers at their marine termination points and slowed down the glacial surge, putting the glaciers back where they had been before 2003. This is a classic example of a negative feedback process--a change in weather conditions which generates a response, but the response creates conditions that tend to dampen the response.


Figure 3. Average temperatures for the only station in southeast Greenland with a century-long temperature record, Angmagssalik (called Ammassalik on the map in Figure 2). Temperatures in southeast Greenland during the 1930s and 1940s were similar to today's temperatures, suggesting that glacial surges like we witnessed in 2005 may have also occurred in the 1930s and 1940s, before we had monitoring capability. Image credit: NASA Goddard.

Commentary
As I commented in my previous post, Arctic sea ice loss appears to have created a new atmospheric circulation pattern that brings more warm air in the Arctic, creating a positive feedback loop that causes even more sea ice loss. This positive feedback loop was a bad news surprise that our climate models did not predict. Now we have evidence of a good news surprise that no model predicted--a negative feedback loop that acts to keep the southeast portion of Greenland's Ice Sheet from runaway glacial acceleration. We can expect many more surprises--good and bad--over the coming decades, as our climate responds to the huge shove human activities are giving it.

Ricky Rood in Copenhagen
Our Climate Change expert, Dr. Ricky Rood, is in Copenhagen for the COP15 climate change treaty negotiations. His latest post, called Have you no sense of decency, sir, at long last? makes for very interesting reading on how the U.S. is "wasting its intellect and time on disruptions designed to play to people at home".

Next post
I'll have another post from the AGU meeting Thursday or Friday this week.

Jeff Masters

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Quoting AwakeInMaryland:
LAMB CHOP!! Awwwwwww.

Guess it's late enough in the Blog.

My mother had my pre-school report card, well, report, many years ago.
Evidently I told my pre-school teacher I wanted to be a lamb when I grew up.

I'm sure an analyst could have a field day with that; or a theologian.


Member Since: August 25, 2009 Posts: 20 Comments: 6785
On a lighter note, those clips sure bring back the memories!
Member Since: July 25, 2006 Posts: 0 Comments: 570
LAMB CHOP!! Awwwwwww.

Guess it's late enough in the Blog.

My mother had my pre-school report card, well, report, many years ago.
Evidently I told my pre-school teacher I wanted to be a lamb when I grew up.

I'm sure an analyst could have a field day with that; or a theologian.
Member Since: August 19, 2008 Posts: 32 Comments: 1918
RE: 604.


Is that not an example of fear-mongering?
Member Since: July 25, 2006 Posts: 0 Comments: 570
Quoting tornadodude:
So, after doing some math and a little chatting, I have come up with a solution.

4 of my friends and I are going to go in on 5 bottles. It will cost us each $17.50 a bottle. Yes that is expensive, but it is from Norway and they are 1.5 liter bottles :P


Is that for the Urge Intense? Whoo Hoo!!

I'm getting lost in all the math, here.
Plus keeping one eye on Craig Ferguson.
Member Since: August 19, 2008 Posts: 32 Comments: 1918
Quoting AwakeInMaryland:
599. I would never have remembered that if you hadn't posted it! Whoa...does anybody remember Miss Shari (sp?) and Lambchop? I'll look for trailer another blogging day... I'm absolutely too dizzy now...and not from any beverages...prob. lack of!


Member Since: August 25, 2009 Posts: 20 Comments: 6785
Anyone notice in the trailer for "An Inconvienent Truth" there is nuke explosion?

Whats up with that?
Its a legitimate question guys.


JF?
Patrap?
Member Since: July 25, 2006 Posts: 0 Comments: 570
Quoting Grothar:


TD, I am sorry, but I believe they only ship .5 liter bottle out of the country, not 1.5 liter. We have to save some for the poor Norwegians, you know.


aww man, that stinks. :P still might do it tho
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting tornadodude:
So, after doing some math and a little chatting, I have come up with a solution.

4 of my friends and I are going to go in on 5 bottles. It will cost us each $17.50 a bottle. Yes that is expensive, but it is from Norway and they are 1.5 liter bottles :P


TD, I am sorry, but I believe they only ship .5 liter bottle out of the country, not 1.5 liter. We have to save some for the poor Norwegians, you know.
Member Since: July 17, 2009 Posts: 71 Comments: 26477
599. I would never have remembered that if you hadn't posted it! Whoa...does anybody remember Miss Shari (sp?) and Lambchop? I'll look for trailer another blogging day... I'm absolutely too dizzy now...and not from any beverages...prob. lack of!
Member Since: August 19, 2008 Posts: 32 Comments: 1918
So, after doing some math and a little chatting, I have come up with a solution.

4 of my friends and I are going to go in on 5 bottles. It will cost us each $17.50 a bottle. Yes that is expensive, but it is from Norway and they are 1.5 liter bottles :P
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting AwakeInMaryland:
Awake in Maryland...That Rudolph trailor is probably from the mid 1960's.

Mid 1960s? MOI?

Na Na Na Na Na Na Na Na Na
Hush, hush
I thought I heard her calling my name now
Hush, hush

Anybody wanna guess?


Hey, do you remember Kukla, Fran and Ollie??

Member Since: August 25, 2009 Posts: 20 Comments: 6785
Awake in Maryland...That Rudolph trailor is probably from the mid 1960's.

Mid 1960s? MOI?

Na Na Na Na Na Na Na Na Na Na Na
Hush, hush
I thought I heard her calling my name now
Hush, hush

Anybody wanna guess?
Member Since: August 19, 2008 Posts: 32 Comments: 1918
Quoting Bordonaro:


I could buy 2 bottles of Patron Tequila and by Vault with the change instead!!


LOL true, hmmm, but it just isnt the same :P
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting tornadodude:
I would pay that for 5 bottles haha I would drink 4 and save the other


I could buy 2 bottles of Patron Tequila and by Vault with the change instead!!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting PensacolaDoug:

Awake in Maryland...That Rudolph trailor is probably from the mid 1960's.

Speaking of trailers.

Anyone notice in the trailer for "An Inconvienent Truth" there is nuke explosion?
Whats up with that?


The General Electric Fantasy Hour 1964!!

Link
Member Since: August 25, 2009 Posts: 20 Comments: 6785
I would pay that for 5 bottles haha I would drink 4 and save the other
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Price List
5 Bottles
USD: Decription:
$67.00 Shipping
$12.50 Bottles
$8.00 Packaging and fees
$87.50 Total
$17.50 Per unit

9 Bottles
USD: Decription:
$89.00 Shipping
$22.50 Bottles
$3.00 Packaging and fees
$114.50 Total
$12.72 Per unit

15 Bottles
USD: Decription:
$89.00 Shipping
$37.50 Bottles
$3.00 Packaging and fees
$129.50 Total
$8.63 Per unit

19 Bottles
USD: Decription:
$131.00 Shipping
$47.50 Bottles
$8.00 Packaging and fees
$186.50 Total
$9.82 Per unit

25 Bottles
USD: Decription:
$163.00 Shipping
$62.50 Bottles
$8.00 Packaging and fees
$233.50 Total
$9.34 Per unit

29 Bottles
USD: Decription:
$179.00 Shipping
$72.50 Bottles
$8.00 Packaging and fees
$259.50 Total
$8.95 Per unit

Member Since: July 17, 2009 Posts: 71 Comments: 26477
Ratz....I killed the blog......again......
Member Since: July 25, 2006 Posts: 0 Comments: 570
Quoting Grothar:


It is only sold in Norway and it means Urge!


Merry Christmas to T-Dude, eh? eh? (:
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Nuclear winter


The "cure" for GW would be worse than the disease!
Member Since: July 25, 2006 Posts: 0 Comments: 570


It is only sold in Norway and it means Urge!
Member Since: July 17, 2009 Posts: 71 Comments: 26477
Quoting Bordonaro:


Look at the shipping price! Are the bottles gold plated??


LOL they are filled with gold!
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting PensacolaDoug:

Awake in Maryland...That Rudolph trailor is probably from the mid 1960's.

Speaking of trailers.

Anyone notice in the trailer for "An Inconvienent Truth" there is nuke explosion?
Whats up with that?


Nuclear winter
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting tornadodude:


I think it will be expensive to get it here from Norway


Look at the shipping price! Are the bottles gold plated??

5 bottles $87.00 bucks! They're NUTS!!

Link
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting Bordonaro:
Tornado Dude! Grothar and you make that soda sound so good, I'm gonna see if I can order some, after the first of year..


Can't get it, never will.
Member Since: July 17, 2009 Posts: 71 Comments: 26477

Awake in Maryland...That Rudolph trailor is probably from the mid 1960's.

Speaking of trailers.

Anyone notice in the trailer for "An Inconvienent Truth" there is nuke explosion?
Whats up with that?
Member Since: July 25, 2006 Posts: 0 Comments: 570
Quoting Grothar:
Must try and get some sleep time. Everyone stay well. For those who wish for snow, may you get as much as you want. Tis the season.

Say, Good Night, Gracie!!!!!!


have a good one Grothar!
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting StSimonsIslandGAGuy:
tornadodude, are you suggesting that as an underage fratboy you have access to alcohol?

I can't believe it.

What a preposterous rumor, not worth contradicting :)
Quoting PensacolaDoug:



You saying he'll hafta splurge for some urge?


LOL you guys crack me up
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting tornadodude:


ummmm....

dont you mean a cup of Urge? (:

LOL!

I've been meaning to ask --
Guess it's one for Grothar...what does "Urge" mean in Norwegian? Or does "Urge" still mean "Urge?" I mean...really...do Norwegians get the joke? Is this like bagpipes and kilts? Everyone gets the joke except the Scots?
Member Since: August 19, 2008 Posts: 32 Comments: 1918
Must try and get some sleep time. Everyone stay well. For those who wish for snow, may you get as much as you want. Tis the season.

Say, Good Night, Gracie!!!!!!
Member Since: July 17, 2009 Posts: 71 Comments: 26477
Quoting tornadodude:


I think it will be expensive to get it here from Norway



You saying he'll hafta splurge for some urge?
Member Since: July 25, 2006 Posts: 0 Comments: 570
Awake in Maryland...That Rudolph trailor is probably from the mid 1960's.

SNOOPY SNOW!!

Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting Bordonaro:
Tornado Dude! Grothar and you make that soda sound so good, I'm gonna see if I can order some, after the first of year..


I think it will be expensive to get it here from Norway
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Quoting StSimonsIslandGAGuy:


Cup of Copenhagen spit or Skoal? :P


Urge and Vodka lol
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Member Since: Posts: Comments:
Tornado Dude! Grothar and you make that soda sound so good, I'm gonna see if I can order some, after the first of year..
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting AwakeInMaryland:
Geoff...
"I don't know if there'll be snow,
but have a cup of cheer!"

Say, do you know where/when
"A Christmas Story" is on this year?

Please don't tell me CBS -- sounded like it was "Crummy Butcher Sadists" for Rudolph!


Catch 24 Hours of this holiday classic, starting Christmas Eve at 8/7c! TBS

Member Since: Posts: Comments:
Grothar told me wedlock killed Socrates (j/k).

Did Bordonaro see those students' writings?
Hilarious!
Member Since: August 19, 2008 Posts: 32 Comments: 1918
Quoting AwakeInMaryland:
Geoff...
"I don't know if there'll be snow,
but have a cup of cheer!"


ummmm....

dont you mean a cup of Urge? (:
Member Since: June 28, 2006 Posts: 25 Comments: 8360
Geoff...
"I don't know if there'll be snow,
but have a cup of cheer!"

Say, do you know where/when
"A Christmas Story" is on this year?

Please don't tell me CBS -- sounded like it was "Crummy Butcher Sadists" for Rudolph!
Member Since: August 19, 2008 Posts: 32 Comments: 1918
Quoting Orcasystems:


watch it.. I saved that remark of yours about wanting snow....
Stay up as long as you like, Sir.
Member Since: Posts: Comments:
564. Skyepony (Mod)
Has anyone seen where this will be available to the public? India's version of quikscat launched in Sept..

NASA Signs Agreement With ISRO For Indian Satellite

US space agency NASA has signed an agreement with ISRO to use data from Indian satellite Oceansat-2, for various American agencies for research activities, including weather forecasting.

Launched on September 23, 2009 using the Polar Satellite Launch Vehicle from Sriharikota, Oceansat-2; is designed to provide service continuity for operational users of the Ocean Colour Monitor (OCM) instrument on Oceansat-1.

The agreement with the Indian Space Research Organisation will lead to the use of data from Oceansat-2 for various US agencies for research, education and other activities of public good including weather forecasting.

The Letter of Intent in this regard was signed by Michael H Freilich, Director Earth Science Division, National Aeronautics and Space Administration; Mary E Kicza Assistant Administrator for Satellite and Information Science of the Oceanic and Atmospheric Administration; and R R Navalgund, Director, Space Application Centre, ISRO.
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Quoting PcolaDan:





ohhh I like that one... that would be a good avatar for shep
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About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.