Study shows increased summer melting not increasing annual movement of Greenland ice sheet

Nov 19, 2013 by Bob Yirka report
Isua Supracrustal Belt Isua, south-west Greenland. Credit: University of Washington.

(Phys.org) —A team with members from Scotland, the U.K. and Australia has found that despite record melting in the summer of 2012, the Greenland ice sheet is not slipping faster into the sea. The team reports on how they set up poles in the ice and measured their movement throughout the year in their paper published in Proceedings of the National Academy of Sciences.

For several years, climate scientists have been worried about the possibility of causing the Greenland to slide right off the continent into the sea, causing a massive sudden rise in worldwide . The worry came about as temperature increases caused more melting which led to water making its way beneath the ice sheet. That water would then lead to less friction and thus faster movement of the ice sheet.

But, according to the results of the researchers studying the problem, that doesn't appear to happening—instead, the increased water flow below the ice in the summer, appears to put the brakes on sliding on the water as it freezes in place the following winter, resulting in less movement on an annual basis.

The team made this discovery by pounding tall poles into the ice at various locations in the ice sheet and then measuring how far they moved (using GPS ) over the course of a year. In analyzing the data they obtained, the team found that despite record melting in the summer of 2012, which resulted in a dramatic increase in movement (up to twice as fast as normal at times), the ice sheet actually moved 6 percent less than normal over the course of the entire year, as the flow slowed dramatically in the winter due likely to the underneath freezing.

This is good news for the world community, of course, as concerns about a rapid rise in ocean levels rising due to global warming has caused panic in places that would be most impacted—seaside towns and cities and of course those who live on islands. It's important to note that the data suggests that people will have longer to plan for ocean levels rising, not that it won't happen.

Explore further: Coral reveals long-term link between Pacific winds, global climate

More information: Greenland ice sheet motion insensitive to exceptional meltwater forcing, PNAS, Published online before print November 18, 2013, DOI: 10.1073/pnas.1315843110

Abstract
Changes to the dynamics of the Greenland ice sheet can be forced by various mechanisms including surface-melt–induced ice acceleration and oceanic forcing of marine-terminating glaciers. We use observations of ice motion to examine the surface melt–induced dynamic response of a land-terminating outlet glacier in southwest Greenland to the exceptional melting observed in 2012. During summer, meltwater generated on the Greenland ice sheet surface accesses the ice sheet bed, lubricating basal motion and resulting in periods of faster ice flow. However, the net impact of varying meltwater volumes upon seasonal and annual ice flow, and thus sea level rise, remains unclear. We show that two extreme melt events (98.6% of the Greenland ice sheet surface experienced melting on July 12, the most significant melt event since 1889, and 79.2% on July 29) and summer ice sheet runoff ∼3.9σ above the 1958–2011 mean resulted in enhanced summer ice motion relative to the average melt year of 2009. However, despite record summer melting, subsequent reduced winter ice motion resulted in 6% less net annual ice motion in 2012 than in 2009. Our findings suggest that surface melt–induced acceleration of land-terminating regions of the ice sheet will remain insignificant even under extreme melting scenarios.

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NikFromNYC
1.9 / 5 (23) Nov 19, 2013
If a skeptic had ever suggested that melt water would act as glue instead of a Slip 'N Slide, a whole army of activists would have screamed with delight at how crazy and stupid he was, yet:

"...instead, the increased water flow below the ice in the summer, appears to put the brakes on sliding on the water as it freezes in place the following winter, resulting in less movement on an annual basis."

Such mostly unknown *negative* feedbacks suggestions are regularly ridiculed as the supercomputer models that lack them add highly speculatively overall water vapor amplification of the traditional greenhouse effect while the modelers *dishonestly* claim mainstream skeptics are "denying" the basic greenhouse effect.

Did Greenland collapse when Vikings farmed there? Did that WWII plane buried under hundreds of feet of ice magically melt its way down there? CyroSat altimetry suggests only overall loss due ti edge melt while a more humid world affords a growing interior (and Antarctica too).
NikFromNYC
1.8 / 5 (21) Nov 19, 2013
"It's important to note that the data suggests that people will have longer to plan for ocean levels rising, not that it won't happen."

The biggest lie of omission of the now toppling alarmist empire that includes the current US Secretary of The Interior in Orwellian fashion warning that there better not be any skeptics in her alarmist outfit, along with the former Vice President calling for execution worthy charges against those who power your car, is that actual on-the-ground tide gauges going back 150 years, when simply averaged into a global value, show a pencil straight immunity to a now seventy year burst in CO₂. Not a lot of people know that because the media feeds on alarm to retain their profits as the Internet threatens their business model.

I included the latest standard Church & White average of tide gauges in a single glance graphic, showing how NASA's web site indeed lies by omission, by literally omitting the last decade of tide gauge data:
http://postimg.or...zt3eei5/
Maggnus
2.7 / 5 (14) Nov 19, 2013
As usual, Nik screams shrilly about anything he perceives as somehow going against global warming. And, also as usual, he doesn't know what he is talking about. No wonder you have to assemble stools for a living. You prove daily you have little scientific background.

He got one thing right, which also helps to highlight his duplicity. The air IS more humid. It is because warmer air holds more moisture. A chemist would understand this basic fact.
NikFromNYC
1.6 / 5 (19) Nov 19, 2013
My graphic included a "really make a battle out of it" rally cry against skeptics by the senator who sponsored Jim Hansen's alarm announcing Senate presentation with crazy hothouse predictions that failed. His online bio reflects that he is enjoying Ted Turner's whopping *billion* dollar donation to the UN:

"Timothy Wirth is the Vice Chair of the United Nations Foundation and the Better World Fund. Both organizations were founded in 1998 through a major financial commitment from Ted Turner to support and strengthen the work of the United Nations."
NikFromNYC
1.6 / 5 (20) Nov 19, 2013
On the Internet, THIS IS SCREAMING, ASSHOLE!!!

...and dude, try not first calling me scientifically illiterate and then reveal that you know perfectly well I am a dual Ivy League trained and *top* student award winning Ph.D. in carbon chemistry.

I assemble stools now, I see. It's great to know that. In face I did modify a few stools with leather padding. Here's one now, with Buster saying hi, guarding my argon plasma gold film sputter coater:
http://postimg.or...w6g34z1/

Air indeed holds more moisture in a warmer world. I can see this sunlight reflecting moisture now, cooling down Riverside Park near Columbia:
http://tinypic.com/r/2ik3b6v/5
NOM
3 / 5 (10) Nov 19, 2013
We all know what you claim Nick

In face I did modify a few stools
I'm sure you have "modified" several stools to write on the walls of your padded room when the nice men in white coats don't let you on the internet.
geokstr
1.4 / 5 (18) Nov 19, 2013
Nik:

I noticed that a typically abusive ad hominem comment from Maggnus was not downvoted even after you replied. Please remember to downvote all comments that are uncivil otherwise they will think they are more popular than they really are (not that megalomania requires such trivial re-enforcement).

The leftlings here consistently downvote all comments from known political opponents even when asking simple, reasonable questions on non-controversial posts, because politics is their religion and they're fanatics about it too. To them you are not just a skeptic, but since you disagree with them, you have become one of their religion's millions of devils, the embodiment of pure evil, and if they could physically destroy you, they would in a heartbeat.

Calling for the mass execution of all those who don't agree with them is a regular comment ending from Vendicar (Decarian, A, B, C, D, E...whatever) and all his sockpuppets.
NOM
2.7 / 5 (7) Nov 19, 2013
Good point geokstr. Do make a point of downvoting my posts too.
I'd hate to find that I was accidentally being civil.
Maggnus
2.5 / 5 (13) Nov 19, 2013
On the Internet, THIS IS SCREAMING, ASSHOLE!!!


Yep, definitely shrill.

...and dude, try not first calling me scientifically illiterate and then reveal that you know perfectly well I am a dual Ivy League trained and *top* student award winning Ph.D. in carbon chemistr


You're a fraud and a liar. You wear your scientific illiteracy as a badge of honor while shrilly claiming conspiracy and spouting denialism. Still following children around in stores fraud?

I frankly doubt you have the ability to assemble even stools.

NikFromNYC
1.5 / 5 (17) Nov 19, 2013
Maggnus is a sockpuppet for truly insane old school Internet troll Vedicar Decarian, who has spent a decade of his adult life ego massaging himself online since real Ph.D.s and real engineers were suddenly appearing online, suffering a hate ("denier!!!") campaign he could attach to, in earnest. That was all before Climategate quickly pulled the actual big money out any further massive PR campaigns, and Al Gore himself cashed out for $500M Arab petrodollars, *much* more than his failing cable TV show was worth on paper, now Al Jezreera America.

But if I really was a fraud (in what?!) and a liar, might a better counterpoint exist in specific debunkings, rather than the usual snide slander and innuendo?

geokstr: I frivolously *up*-vote lots of "Nik Sux" comments to alert filter users to drama, but I'm not really enough of a Netizen to even ever take seriously a star ratings system. My perceived audience is contemporary book writers, who will find my posts anyway, via Google.
Maggnus
3 / 5 (8) Nov 20, 2013
Of course you would say that. Laughably predictable, albeit combined with a puzzling degree of social ineptitude. You really are a fraud and a liar, and I see no need to legitimize your inept musings with any attempt at reasonable discourse. runrig has done (and continues to do) that, all to watch you melt down into a rambling, drunken-sounding and shrill rant about some conspiracy you think, thinks you matter.

News flash moron - you don't.

You may be able to fool some of those who are already incapable of independent, critical thinking, but those of us who can actually follow the disjointed ramblings and duplicitous content that makes up the bulk of your delusional orations are not fooled.
runrig
2.8 / 5 (4) Nov 20, 2013
.. while the modelers *dishonestly* claim mainstream skeptics are "denying" the basic greenhouse effect.

Mainstream skeptics eh Nik?
I thought you considered Steven Goddard "mainstream". You're always quoting him.
Eg
" Speaking of satellites vs. ground data, today shock jock blogger Steven Goddard presents a simple, ….."
Well it seems not….
"There literally exists no empirical evidence for the atmospheric radiative greenhouse effect version anywhere. Tests that have been performed to empirically demonstrate it have always and consistently failed to find it, among both critics of the atmospheric radiative greenhouse effect and its supporters. Real physical greenhouses exist; the idea of a radiative atmospheric greenhouse effect is a fiction which hijacks the name of the real thing in a real greenhouse."
https://stevengod...-failed/

Denying a GHE at work in the atmosphere is NOT mainstream?
djr
4 / 5 (4) Nov 20, 2013
Surely the more important point to glean from yet more research on the climate - is that the ice melt continues to accelerate. "The worry came about as temperature increases caused more melting " We are constantly assaulted by the "no new warming meme", on this site - but every piece of research reinforces the understanding that - yes the system does continue to warm. Nik et al can spam the site all they want (5 out of 12 comments on this one thread) - but reality marches on. I was very interested to see that when real world evidence mounts up against the denial world view - the Niks of the world are much slower to be so cocky. See - http://phys.org/n...tic.html Collapse of the zooplankton is a very immediate, and troubling possibility. We just have to believe that the Niks of the world do not truly have any influence - and things are changing - see - http://empowerthe...ate-risk
The Alchemist
1 / 5 (11) Nov 21, 2013
Gawd, I wish I could just block certain posters.
This article brings up a good, if absurdist point:
If the Greenland ice sheet did slide into the ocean, the world, particularly the Northern Atlantic, would get colder.
The world would get obviuosly COLDER as a result of AGW.

Neat, huh?
VendicarE
2.4 / 5 (5) Nov 21, 2013
"For several years, climate scientists have been worried about the possibility of global warming causing the Greenland ice sheet to slide right off the continent into the sea, causing a massive sudden rise in worldwide ocean levels. " - Article

Sorry.. But no scientist was ever worried about that impossibility.

Author must have been stoned when he/she wrote that tripe.
runrig
3.7 / 5 (6) Nov 21, 2013
Re Greenland:
The arctic is exquisitely sensitive to forcings, whether SST, Solar, pressure pattern/wind (AO/NAO - similar in effect to ENSO trade/ocean coupling).

Note this correlation with BC (black carbon) deposition in Greenland ice giving an effective increase in insolation – against a melting period in the early 20th ct

http://www.ess.uc...ce07.pdf

"Pronounced increases in BC .. in .. Greenland ice cores extrapolate to a marked impact on early summer climate forcing throughout the Arctic during and after industrialization, with changes largely attributed to winter industrial BC emissions. The median in estimated surface forcing in early summer throughout the Arctic was 0.42 W m–2 prior to 1850, 1.13 Wm–2 during the period 1850-1951, and 0.59 W m–2 after 1951. During the 5yr period of max. industrial BC emissions from 1906-1910, est. surface forcing in the Arctic was 3.2 W m–2, about 8x ave early summer forcing prior to industrialization
Ducklet
1 / 5 (10) Nov 23, 2013
Every time there's a hurricane, typhoon, drought, flood, ice storm, unusual rains, unusual snow, unusually warm, unusually cold, any other weather-related mayhem - or even unusually normal - it's due to global warming. When confronted with the fact that warming has temporary leveled off the alarmists retort that the predictions are only valid at no less than 30/50/75/100 years (it varies) and the theory needs at least 30 years to be proven. But if it's unproven, how do they know all this mayhem is due to it? A theory which by definition needs 50 years to prove isn't worth the bits the PDF occupies. It's completely non-actionable. It's not testable. It's not verifiable. It's not even disprovable. Might as well claim Jesus did it.
djr
3.8 / 5 (4) Nov 23, 2013
Hey Ducklet - you wouldn't want to read the article would you - and maybe comment on the information presented in the article (which does not attribute any catastrophes to global warming) would you? Oh that's right - too busy scoring political points.
Ducklet
1 / 5 (10) Nov 23, 2013
Yes, I read the article. Now, go to the second paragraph and click on the "global warming" link to see previous reporting on the subject on this site. Just last week it featured "Ban says Philippines typhoon a 'warning' on climate change".
Ducklet
1 / 5 (10) Nov 23, 2013
Then, on the 19th there was a story, http://phys.org/n...te.html, which says "Developing countries want rich nations to show how they intend keeping a promise made in 2009 to ramp up finance to $100 billion a year by 2020." But what is this $100b be used to mitigate? More rain? Higher sea levels, and if so how much higher? Less rain? Less crops? Different crops? Warmer temperatures? Colder temperatures? Note the commitment of 2020 - that's only 7 years, definitely a tad shorter than any 30-year scope.
djr
3.5 / 5 (6) Nov 23, 2013
Like I say Ducklet - busy scoring political points - rather than addressing the content of the article. As you are obviously not aware - the ice sheets continue to melt, the oceans continue to warm, the ocean levels continue to rise - so it is quite legitimate to remain concerned about what the scientists are telling us - that the system continues to warm.
goracle
1.9 / 5 (9) Nov 23, 2013
On the Internet, THIS IS SCREAMING, ASSHOLE!!!


Yep, definitely shrill.

...and dude, try not first calling me scientifically illiterate and then reveal that you know perfectly well I am a dual Ivy League trained and *top* student award winning Ph.D. in carbon chemistr


You're a fraud and a liar. You wear your scientific illiteracy as a badge of honor while shrilly claiming conspiracy and spouting denialism. Still following children around in stores fraud?

I frankly doubt you have the ability to assemble even stools.


Real scientists don't quote WUWT or phony Lords as sources.
VendicarE
3 / 5 (4) Nov 24, 2013
About NikkieTard's source...

"Monckton claimed that he has developed a cure for Graves' Disease, AIDS, Multiple Schlerosis, the flu, and the common cold. This is no joke–he actually filed an application to patent a "therapeutic treatment" in 2009. Is it homeopathy? Massive doses of vitamin C? The world waits with bated breath."

http://bbickmore....p-sheet/
NikFromNYC
1 / 5 (7) Nov 25, 2013
Monckton indeed has Graves disease, an auto-immune condition, and a drug he ran into that seemed to help also lowered virus count in an AIDs patient he met, and Gorebots seized on this after digging up a rambling interview where Chris bragged about it a bit, but even climate alarmist dominated Wikipedia admits that: "on Australian radio, Monckton refrained from claiming any cures."

But given a YouTube propaganda video, Monckton becomes a riotous crackpot, so misfit Climate Crusaders can sport green halos where before they felt lowly and miserable because the rapidly dynamic world was complicated and confusing instead of utterly crystal clear, like a bullet, a diamond bullet, right through their foreheads, to paraphrase Marlon Brando up the river in Apocalypse Now.

It's not that there's a great conspiracy to disinform, merely people who with passion proudly see an illusion of a black and white world of pure saints (politicians) fighting a doomsday battle against pure demons (deniers).
goracle
2.3 / 5 (3) Dec 06, 2013
Monckton indeed has Graves disease, an auto-immune condition, and a drug he ran into that seemed to help also lowered virus count in an AIDs patient he met, and Gorebots seized on this after digging up a rambling interview where Chris bragged about it a bit, but even climate alarmist dominated Wikipedia admits that: "on Australian radio, Monckton refrained from claiming any cures."

That didn't stop him from claiming to be a member of the House of Lords. You try desperately to defend your use of a known BS artist as a source, but few are buying it.
Monckton claiming to have cured HIV, etc. http://climatecro...-change/

Not a member of the House of Lords: http://www.parlia...onckton/

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