Ice-loss moves the Earth 250 miles down

May 11, 2014
Earth

At the surface, Antarctica is a motionless and frozen landscape. Yet hundreds of miles down the Earth is moving at a rapid rate, new research has shown.

The study, led by Newcastle University, UK, and published this week in Earth and Planetary Science Letters, explains for the first time why the upward motion of the Earth's crust in the Northern Antarctic Peninsula is currently taking place so quickly.

Previous studies have shown the earth is 'rebounding' due to the overlying ice sheet shrinking in response to climate change. This movement of the land was understood to be due to an instantaneous, elastic response followed by a very slow uplift over thousands of years.

But GPS data collected by the international research team, involving experts from Newcastle University, UK; Durham University; DTU, Denmark; University of Tasmania, Australia; Hamilton College, New York; the University of Colorado and the University of Toulouse, France, has revealed that the land in this region is actually rising at a phenomenal rate of 15mm a year – much greater than can be accounted for by the present-day elastic response alone.

And they have shown for the first time how the mantle below the Earth's crust in the Antarctic Peninsula is flowing much faster than expected, probably due to subtle changes in temperature or chemical composition. This means it can flow more easily and so responds much more quickly to the lightening load hundreds of miles above it, changing the shape of the land.

Lead researcher, PhD student Grace Nield, based in the School of Civil Engineering and Geosciences at Newcastle University, explains: "You would expect this rebound to happen over thousands of years and instead we have been able to measure it in just over a decade. You can almost see it happening which is just incredible.

"Because the mantle is 'runnier' below the Northern Antarctic Peninsula it responds much more quickly to what's happening on the surface. So as the glaciers thin and the load in that localised area reduces, the mantle pushes up the crust.

"At the moment we have only studied the vertical deformation so the next step is to look at horizontal motion caused by the ice unloading to get more of a 3-D picture of how the Earth is deforming, and to use other geophysical data to understand the mechanism of the flow."

Since 1995 several ice shelves in the Northern Antarctic Peninsula have collapsed and triggered ice-mass unloading, causing the solid Earth to 'bounce back'.

"Think of it a bit like a stretched piece of elastic," says Nield, whose project is funded by the Natural Environment Research Council (NERC). "The ice is pressing down on the Earth and as this weight reduces the crust bounces back. But what we found when we compared the ice loss to the uplift was that they didn't tally – something else had to be happening to be pushing the solid Earth up at such a phenomenal rate."

Collating data from seven GPS stations situated across the Northern Peninsula, the team found the rebound was so fast that the upper mantle viscosity - or resistance to flow - had to be at least ten times lower than previously thought for the region and much lower than the rest of Antarctica.

Professor Peter Clarke, Professor of Geophysical Geodesy at Newcastle University and one of the authors of the paper, adds: "Seeing this sort of deformation of the at such a rate is unprecedented in Antarctica. What is particularly interesting here is that we can actually see the impact that glacier thinning is having on the rocks 250 miles down."

Explore further: East Antarctica is sliding sideways: Ice loss on West Antarctica affecting mantle flow below

More information: "Rapid bedrock uplift in the Antarctic Peninsula explained by viscoelastic response to recent ice unloading." Grace A. Nield, Valentina R. Barletta, Andrea Bordoni, Matt A. King, Pippa L. Whitehouse, Peter J. Clarke, Eugene Domack, Ted A. Scambos, Etienne Berthier. Earth and Planetary Science Letters. To be published Vol 397, 1 July, 2014.

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User comments : 35

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Socratic
1.1 / 5 (28) May 11, 2014
You can't see it on the surface, where everything is frozen solid, but ho-boy. Scientific grantwhistlegadgetry sure shows dynamic super hootenanny change a-broilin' down where nobody can tell but us!!!
verkle
1.3 / 5 (19) May 11, 2014
This article left me with a sense that the scientists really don't know what is causing this uplift.
plaasjaapie
1 / 5 (17) May 11, 2014
What a whopper!
Caliban
4.8 / 5 (20) May 11, 2014
Pretty simple, really-- reduced pressure(from ice unloading at the surface) in the contact zone between crust and upper mantle = decreased viscosity/density, and thus, faster infilling/bouyancy of the material, and and uptick in uplift.

Geophysics!
akshayjamwal
1 / 5 (5) May 12, 2014
Interesting article, but the title is quite misleading.
Noodle_Naut
1.5 / 5 (11) May 12, 2014
It just means it is not a slow process, that the buoyancy adjustment is being taken care of by deeper less viscus material...perhaps very deep. Whatever can react faster does...it is just following the path of least resistance. Probably is as much push as pull. As the oceans push down with the extra weight what is displaced goes somewhere...like under the continents.

It might mess up their math for other presumed long reactions in the past, but it is what it is.

Really? Suggesting the rise is not because of the mass unloading? Come on. What are you suggesting? A hotspot is heating up under Antarctica? OK, maybe my list of alternatives is small, what else is there? No plates being shoved under the thing, the Earth is not slowing reducing tropical bulge.

Crazy ideas: more water in the air making more atmospheric weight at the tropics.
Solar activity affects the magnetosphere which affects where the force lines converge.
Coriolis reaction to loss of mass twisting edge vs center.
Lex Talonis
2 / 5 (7) May 12, 2014
Simplifying this a heap.... if ONE meter of ice melts and flows away, from a HUGE ice sheet, then the relief of that pressure will be compensated by a general levelling out of that depression, by the fact that the world is a spinning ball of liquid rock with a crust on it.

Removing ONE metric ton per square meter, means that loss of pressure, will balance out by the up lifting on one metric ton of rock to balance out the surface of the sphere.

T'2 = T2 - (v/c)2T2 whence

T' = T(1 - (v/c)2)1/2 = T/γ, where γ = 1/(1 - (v/c)2)1/2.
alfie_null
5 / 5 (14) May 12, 2014
This article left me with a sense that the scientists really don't know what is causing this uplift.

Rather, you and I know little. Scientists know significantly more, but not all. Through this process, including publishing, they continue to learn. Your post leaves me with a sense that you are trying to spread FUD.
Shootist
1.9 / 5 (12) May 12, 2014
Not news.
TechnoCreed
4.1 / 5 (13) May 12, 2014
What are all those comments of uninterested readers all about? When an article refers to a scientific paper, please take the time to read the it before commenting; doing due diligence is part of the scientific method and it would prevent the posting of ridiculous comments.

I know... the author of this article did not provide a direct link. Are you all so lazy that you find it too hard to do a simple Google search? Here is a link to the paper that this article is referring to: http://www.scienc...14002519
FrankTrades
1 / 5 (10) May 12, 2014
Is data from the ultra-cold winter of 2013-14 included?
no fate
4.5 / 5 (11) May 12, 2014
Is data from the ultra-cold winter of 2013-14 included?


It's the southern Hemisphere. Their winter doesn't straddle the new year and it wasn't ultra cold.
aj7stars
2.7 / 5 (3) May 12, 2014
Has anyone thought of the calculation of Earth Elasticity in comparison to raising water levels due to ice melt? I have a simple belief, that the Earth has gone through these processes in the past and will continue in the future, with human activities speeding up the process, hence wild weather activities.
Osiris1
1 / 5 (5) May 12, 2014
Sheeesh! IN a million years the place will be a plateau of minimum altitude away from the coast of 15,000 feet!?
mooster75
4.5 / 5 (8) May 13, 2014
Is data from the ultra-cold winter of 2013-14 included?


It's the southern Hemisphere. Their winter doesn't straddle the new year and it wasn't ultra cold.

On the other hand, we now know that there is at least some overlap between climate deniers and flat earthers. Any data can be useful...
mooster75
4.3 / 5 (6) May 13, 2014
Interesting article, but the title is quite misleading.

I'm curious as to what you were expecting...
Stevepidge
1 / 5 (6) May 13, 2014
Who cares. I'll be long dead before "climate change" affects the earth in any dramatic fashion. Besides, according to these same scientists the universe is doomed to ultimate heat death and seeing as nothing can escape heat death why the hell should I care about this? I'll will have been annihilated as a sentient being, all my thoughts, loves, fears, dreams and offspring along with the rest of the entire universe will have existed for nothing. Therefore in the meantime, with the time I have left here as a sentient being I could give two shits less what is going on under the ice in Antartica. In other words I'm not buying your science, because your science denies ANY meaning for existence outside of the here and now.
Maggnus
5 / 5 (8) May 13, 2014
Who cares. I'll be long dead before "climate change" affects the earth in any dramatic fashion. Besides, according to these same scientists the universe is doomed to ultimate heat death and seeing as nothing can escape heat death why the hell should I care about this? I'll will have been annihilated as a sentient being, all my thoughts, loves, fears, dreams and offspring along with the rest of the entire universe will have existed for nothing. Therefore in the meantime, with the time I have left here as a sentient being I could give two shits less what is going on under the ice in Antartica. In other words I'm not buying your science, because your science denies ANY meaning for existence outside of the here and now.
This was an interesting back-handed stab at injecting religion into the discussion. The comment "why the hell should I care about this...because your science denies any meaning for existence" is the true underpinning of most of the denialist agenda. God will save us!
TegiriNenashi
1 / 5 (5) May 13, 2014
"...The comment "why the hell should I care about this...because your science denies any meaning for existence" is the true underpinning of most of the denialist agenda..."

People love simplistic explanations. "He is paid industry shill!" "They are watermellons!" "Those evil Israelis are poisoning water in Cairo!" Stick to the facts and we'll be OK.
Gaby_64
4.3 / 5 (6) May 13, 2014
you should care because earth is a system and changes in one location will affect others, which will cascade down to affecting you and your offspring's.

"Our lives are not our own. We are bound to others, past and present, and by each crime and every kindness, we birth our future."
Caliban
5 / 5 (9) May 13, 2014
Who cares. I'll be long dead before "climate change" affects the earth [...]sentient being I could give two shits less what is going on under the ice in Antartica. In other words I'm not buying your science, because your science denies ANY meaning for existence outside of the here and now.


The Science only explains the how and why of the way things work. If you are looking for meaning, then you'll have to look elswhere --afterall, an auto-owner's manual doesn't tell you to join the Peace Corps, does it?

As you search for meaning in your life, one would hope that it would lead you to an understanding that the rest of Life is just as valuable and meaningful as your own, and just as worthy of protecting and preserving, now and in the future.

For this reason --if for no other-- AGW is of gravest concern.

Or, you can indulge this faux nihilism, obey your fascist masters, and foredoom the living and the yet unborn. Just like a "Good German".

Ever hear of the Holocaust?

thermodynamics
5 / 5 (9) May 13, 2014
Is data from the ultra-cold winter of 2013-14 included?


It's the southern Hemisphere. Their winter doesn't straddle the new year and it wasn't ultra cold.

On the other hand, we now know that there is at least some overlap between climate deniers and flat earthers. Any data can be useful...


I wish I could give you a 10 for that one, but I have to only give you five stars.
Stevepidge
1.7 / 5 (6) May 13, 2014
Some of these comments are claptrap politicized drivel. If all life in the entire universe is doomed to eventual heat death why does it matter that anyone survives? All of your AGW will be ultimately meaningless. All of your science will be gone.... There will be no human race, no Obama, No Hitler, nothing. I don't need a damn manual to live life, I need the freedom to choose how and where I live my life, to be free of the miscreants and parasites that have infected modern society. BTW please explain how the holocaust means ANYTHING if the universe is doomed to heat death and we are biological machines ultimately predictable in our motivations and actions? Please, in all of your infinite collective BS explain why anyone should care if our ultimate fate is annihilation. Why should I care about a species who can't accept their own meaninglessness they purport to be the ultimate fate of all? Answer this question or screw you all.
Stevepidge
1.7 / 5 (6) May 13, 2014
you should care because earth is a system and changes in one location will affect others, which will cascade down to affecting you and your offspring's.

"Our lives are not our own. We are bound to others, past and present, and by each crime and every kindness, we birth our future."


Simplistic crap. Why does it matter? Everything we hope to achieve as a species will be for not. EVERYTHING... This conversation and every other interaction between man will be obliterated by the cold dark deep depths of a dead universe NEVER to see the light of life again.

and your quote, while poignant is from a terrible movie that provides no context to the question posed.
Caliban
5 / 5 (7) May 13, 2014
you should care because earth is a system and changes in one location will affect others, which will cascade down to affecting you and your offspring's.

"Our lives are not our own. We are bound to others, past and present, and by each crime and every kindness, we birth our future."


Simplistic crap. Why does it matter? Everything we hope to achieve as a species will be for not. EVERYTHING... This conversation and every other interaction between man will be obliterated by the cold dark deep depths of a dead universe NEVER to see the light of life again.

and your quote, while poignant is from a terrible movie that provides no context to the question posed.


Well then, just give up your meaningless struggle and cease wasting our time with your meaningless maunderings about the overwhelming meaninglessness of it all.

Stevepidge
1 / 5 (5) May 13, 2014

Well then, just give up your meaningless struggle and cease wasting our time with your meaningless maunderings about the overwhelming meaninglessness of it all.



After you quit trying to convince me of the importance of ice floes under the antartic and how I should fork over countless sums of money so the earth can survive a little longer, when in the end it doesn't even matter. Unless, you want to admit we aren't merely deterministic organic machines in an ultimately doomed universe. In which case I recend my pessimism.
Captain Stumpy
5 / 5 (9) May 13, 2014
After you quit trying to convince me of the importance of ice floes under the antartic
@Stevepidge
aint no one here trying to "convince you" of anything bubba. There is fact. there is empirical data. what you want o do with it is your problem. your children etc will live with the consequences (if you have any).
No one forcing you here on the SCIENCE site. no one forcing you to read.

Please feel free to leave at any time.
THE EMPIRICAL DATA and the facts are what scientific people worry about, and there IS a possibility of living after the "heat death" as you describe. at our current level of technology? maybe not. future tech? most likely so.

You want to give it up, fine. don't whine here about it. this site is for proactive thinkers to use empirical data finding solutions to reality's problems and keeping humanity around a little longer, just to learn more. if ya don't like it, LEAVE

PS keep your pessimism. no one cares
Caliban
5 / 5 (6) May 13, 2014

Well then, just give up your meaningless struggle and cease wasting our time with your meaningless maunderings about the overwhelming meaninglessness of it all.



After you quit trying to convince me of the importance of ice floes under the antartic and how I should fork over countless sums of money so the earth can survive a little longer, when in the end it doesn't even matter. Unless, you want to admit we aren't merely deterministic organic machines in an ultimately doomed universe. In which case I recend my pessimism.


The disease you suffer from --and seek to afflict us with-- is not pessimism, but narcissism.

Regardless, you'll find no answer to your ailment here. So STFU with your whining prevarication, already.
no fate
4.3 / 5 (7) May 14, 2014

Well then, just give up your meaningless struggle and cease wasting our time with your meaningless maunderings about the overwhelming meaninglessness of it all.



After you quit trying to convince me of the importance of ice floes under the antartic and how I should fork over countless sums of money so the earth can survive a little longer, when in the end it doesn't even matter. Unless, you want to admit we aren't merely deterministic organic machines in an ultimately doomed universe. In which case I recend my pessimism.


https://www.youtu...IBJ_MKas

Maggnus
5 / 5 (7) May 14, 2014

Well then, just give up your meaningless struggle and cease wasting our time with your meaningless maunderings about the overwhelming meaninglessness of it all.



After you quit trying to convince me of the importance of ice floes under the antartic and how I should fork over countless sums of money so the earth can survive a little longer, when in the end it doesn't even matter. Unless, you want to admit we aren't merely deterministic organic machines in an ultimately doomed universe. In which case I recend my pessimism.


https://www.youtu...IBJ_MKas



Classic no fate, fits here perfectly!!
Jonseer
5 / 5 (2) May 14, 2014
I wonder if they are checking to see if this is resulting in greater volcanic activity. I'm not imagining catastrophic changes, just a much greater frequency either there or in the Andes perhaps or the volcanic Scotia arch.
bluehigh
4 / 5 (4) May 14, 2014
The disease you suffer from --and seek to afflict us with-- is not pessimism, but narcissism.


Its neither in or of itself.

The philosophy is Existential Nihilism.
.
Whydening Gyre
5 / 5 (4) May 14, 2014
The disease you suffer from --and seek to afflict us with-- is not pessimism, but narcissism.


Its neither in or of itself.

The philosophy is Existential Nihilism.
.

Wow... Cloud Atlas makes more and more sense.....
Caliban
5 / 5 (6) May 14, 2014
The disease you suffer from --and seek to afflict us with-- is not pessimism, but narcissism.


Its neither in or of itself.

The philosophy is Existential Nihilism.
.


@blue high-

A closer reading of this troll's posts will make it clear to you that the "Existential Nihilism" is merely a pose.

Just another godder Narcissist trying to force everyone to equate a Meaningful Existence with the Necessity of God.

Clever, huh?
bluehigh
4.3 / 5 (6) May 14, 2014
@Calaban ... Yes, I now see you mentioned the nihilism previously. Sly type of clever.

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