Uh, oh. New study shows Earth's internal heat drives rapid ice flow and subglacial melting in Greenland

Distant history of the North Atlantic region contributes to the present-day ice loss


From the GFZ German Research Centre for Geosciences

To understand Greenland’s ice of today researchers have to go far back into Earth’s history. The island’s lithosphere has hot depths which originate in its distant geological past and cause Greenland’s ice to rapidly flow and melt from below. An anomaly zone crosses Greenland from west to east where present-day flow of heat from the Earth’s interior is elevated. With this anomaly, an international team of geoscientists led by Irina Rogozhina and Alexey Petrunin from the GFZ German Research Centre for Geosciences could explain observations from radar and ice core drilling data that indicate a widespread melting beneath the ice sheet and increased sliding at the base of the ice that drives the rapid ice flow over a distance of 750 kilometres from the summit area of the Greenland ice sheet to the North Atlantic Ocean.

The North Atlantic Ocean is an area of active plate tectonics. Between 80 and 35 million years ago tectonic processes moved Greenland over an area of abnormally hot mantle material that still today is responsible for the volcanic activity of Iceland. The mantle material heated and thinned Greenland at depth producing a strong geothermal anomaly that spans a quarter of the land area of Greenland. This ancient and long-lived source of heat has created a region where subglacial meltwater is abundant, lubricating the base of the ice and making it flow rapidly. The study indicates that about a half of the ice in north-central Greenland is resting on a thawed bed and that the meltwater is routed to the ocean through a dense hydrological network beneath the ice.

The team of geoscientists has now, for the first time, been able to prove strong coupling between processes deep in the Earth’s interior with the flow dynamics and subglacial hydrology of large ice sheets: “The geothermal anomaly which resulted from the Icelandic mantle-plume tens of millions of years ago is an important motor for today’s hydrology under the ice sheet and for the high flow-rate of the ice” explains Irina Rogozhina. “This, in turn, broadly influences the dynamic behaviour of ice masses and must be included in studies of the future response to climate change.”


These secrets of Greenland’s past have been hidden by the 3 km thick ice sheet covering the landmass and are now revealed by the researchers using an innovative combination of computer models and data sets from seismology, gravity measurements, ice core drilling campaigns, radar sounding, as well as both airborne, satellite and ground-based measurements on the thickness of the ice cover. The location and orientation of the zone of elevated geothermal heat flow shows where Greenland moved over the Iceland mantle plume.

This unexpected link between hotspot history and ice sheet behaviour shows that the influences on ice sheets span a huge range of timescales from the month by month changes of the ice cover to the multi-million year epochs over which the Earth’s mantle and tectonic plates evolve. Besides this, the results of the study provide an independent test for models of the opening of the North Atlantic which after a three-decade-long debate still is not fully understood.


Irina Rogozhina, Alexey G. Petrunin, Alan P. M. Vaughan, Bernhard Steinberger, Jesse V. Johnson, Mikhail K. Kaban, Reinhard Calov, Florian Rickers, Maik Thomas and Ivan Koulakov: “Melting at the base of the Greenland ice sheet explained by Iceland hotspot history”, NATURE GEOSCIENCE, Advance Online Publication, 04 April 2016, DOI: 10.1038/NGEO2689 http://dx.doi.org/10.1038/NGEO2689

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Ben of Houston
April 6, 2016 5:20 am

So, in summary: Lava is hot and hot things melt ice.
Sorry, I just couldn’t resist, but we have to translate it into something our politicians can understand

Reply to  Ben of Houston
April 6, 2016 7:31 am

Can’t you simplify it any more, because I still think they will be hard put to grasp this concept! Adding “subsidies to friends” may help.

Reply to  Andrew Harding
April 6, 2016 11:49 am

Sorry, but no matter how hard you simplify it, you’ll never get down to what they care about: “how can we tax it?”
Actually, that comes after: “how can we get lava to donate to us”?

old construction worker
Reply to  Ben of Houston
April 7, 2016 2:42 am

According to Big AL the earth’s internal heat is several thousand degrees “hot”.

Reply to  old construction worker
April 7, 2016 5:52 am

He said “millions of degrees a few kilometers down..”

D. J. Hawkins
Reply to  old construction worker
April 7, 2016 5:57 am

I believe he said “several million”.

FJ Shepherd
April 6, 2016 5:31 am

So, does this mean that the “health” of the Greenland ice sheet is in danger because of geothermal activity? Does this mean that lava and CO2 are conspiring together to destroy mankind? Is it worse than we thought?

Reply to  FJ Shepherd
April 6, 2016 5:42 am

It’s always worse than we thought!

Reply to  mikerestin
April 6, 2016 7:24 am

Unless we don’t think about it. Then, it’s not too bad.

Reply to  mikerestin
April 6, 2016 11:50 am

It’s always worse than we thought, and much, much later…

Michael D
Reply to  FJ Shepherd
April 6, 2016 11:23 pm

Yes, it’s worse than we thought, but by reducing carbon footprints and buying carbon offsets we can cool that lava and save the Statue of Liberty from flooding. I mean that’s a big reservoir of lava, and we can’t just do nothing.

April 6, 2016 5:41 am

Besides this, the results of the study provide an independent test for models of the opening of the North Atlantic which after a three-decade-long debate still is not fully understood.

There are so many things wrong with that statement.
First, there is no such thing as an independent test anymore. Secondly, with a 97% certainty, the opening of the North Atlantic is caused by CO2. An thirdly, with our high powered supercomputers and impeccable models, we fully understand everything… and if you don’t understand, you are going to jail.

April 6, 2016 5:53 am

This for an 11-year old debunking of the Iceland Plume http://www.mantleplumes.org/Iceland1.html
I see the new hotshots are using modelling – which is putting the cart before the horse

Reply to  kenarfblog
April 6, 2016 4:27 pm

Models, in and of themselves, are not the problem any more than adjustments are. The trick is to do them right. CMIP3/5 are very badly off the beam, yes. But how about Lewis, Curry (2015)? Not so bad, that one.
NOAA, Haddy4, and Wicked Uncle GISS maladjust the data, yes. But that doesn’t mean that correct adjustments cannot be made. And raw data, alas, will not do. Homogenization is badly misapplied. But that does not mean that this powerful (but risky) tool cannot be applied correctly.
Adjustments are necessary. Models can be highly useful. All the more reason to get it right, and to be able to easily correct if they turn out wrong. Just because there are bad actors does not mean that the play cannot be redeemed.
We can. We will.

Reply to  kenarfblog
April 6, 2016 4:29 pm

The Iceland plume has not been “debunked;” it is a hypothesis that attempts to explain excess vulcanism- all any “plume” attribution is. If you read the rest of the links that appear on yours, then you find that “mantle plumes” are hypothetical – not proven – entities, and by no means all or even most of them reflect the entire pattern of properties that Foulger complains the Iceland region lacks. Looked at in terms of what we actually know, Foulger’s premises are easily as problematic as he thinks an Ice Land plume hypothesis is. He might well be right, but given how very little we really know about the genesis and evolution of hit spots, he’s probably just as likely to be wrong – along with the folks whose ideas he doesn’t like.

Reply to  Duster
April 6, 2016 4:30 pm

“… hit spots…” -> “hot spots” – arrgh.

Smart Rock
Reply to  Duster
April 7, 2016 2:45 pm

Not he, she. Professor Gillian Foulger.

Smart Rock
Reply to  kenarfblog
April 7, 2016 4:58 pm

Thanks Kenarfblog for posting that link, it reminded me of how sceptical I was about mantle plumes when I first heard about them in 1965. I never thought much about them since then because they don’t impact much on day-to-day practical geology, until – coincidentally last month when I was digging up some info on the Mid-Continent Rift and how it affected the Lake Superior region. A mantle plume was invoked and it turns out that mantle plumes are deemed to be responsible for virtually all major igneous events – even though nobody has ever seen one, and nobody knows what they are really like. It’s quite reminiscent of how “climate change” is invoked for every snowstorm, hurricane, drought, etc.
The one piece of really convincing evidence for something like a mantle plume is the Hawaiian Islands, The only active volcano is on the big island at the southeast end of the chain, and the volcanos get progressively older as you go from island to island in a northwesterly direction. It’s pretty convincing that the Pacific Plate is moving northwest over a stationary hot spot that causes periodic volcanic activity.
The second (presumed) candidate for a mantle plume is Iceland, because it sits on the Mid-Atlantic Ridge, but there’s much more extensive vulcanism there than anywhere else on the ridge. And it’s been going on since the start of the Atlantic opening. There was a lot of volcanic and intrusive magmatic activity in western Scotland and eastern Greenland, which at that time were joined – it’s called the North Atlantic Igneous Province. As Greenland and Scotland drifted away, volcanic activity continued in Iceland. So these authors are absolutely right, there probably is some residual heat in the mantle under central Greenland, and yes, it’s possible that it might assist in melting the basal layer of ice.
But keep it in perspective. Typical heat flow in continental areas is 65 mW/m² and 101 mW/m² in oceanic areas, and of course it’s much more in active volcanic areas. But those number are MILLIWATTS, and they are trivial compared with heat received from the sun. So it will only have a detectable effect where it’s isolated from surface weather for very long periods – e.g. at the base of a continental ice sheet.
What bothered me about the mantle plume hypothesis is that it was so vague. A “stream” of heat was supposed to move up from lower mantle to upper mantle and cause melting with resultant magmatic activity at or near the surface. I objected to this saying – it can’t be heat transported by conduction because that would disperse heat in all directions and form a much larger “hot area” and not a “hot spot”. It couldn’t be convection because it was deemed to be a one-way movement of heat, and of course radiation won’t work in the dark. It turns out that a fourth mode of heat transport was invented for mantle plumes, called “advection”. This seems to mean “hot stuff moves up and cold stuff moves aside to make room for the hot stuff”. Well, that was really quite obvious that if there were mantle plumes
There is an active debate about whether mantle plumes really exist. It’s quite strikingly similar to the climate-change/global warming debate. There is a “consensus” about mantle plumes, with a few strong advocates and a large majority who haven’t really studied the subject, who just go along with it. There’s a smaller group of “sceptics” and Gillian Foulger is one of the leading sceptics. The debate is quite vigorous, but (and here’s the BIG difference) it’s all quite cordial and there are no accusations of sceptics being funded by Koch Industries, or calls for criminal prosecution. Of course, even the strongest proponents of mantle plumology are claiming that it will make the earth uninhabitable and cause mass extinctions, etc. etc.
Here are two quotes from Gillian Foulger at
and you can almost use them, word for word, in the climate “debate” by replacing “hot plume” with “CO2 related warming”

It is curious that the best defence of plumes, after over 30 years of study, is that they are not understood, cannot be seen, and have unobservable consequences. The lack of evidence for hot plumes is matched only by the lack of doubt that they exist. We are told that the hypothesis yields “quantitative testable predictions”, but what exactly are these? Plumes have been proposed to come from almost any depth, to be stationary or move, to be long- or short-lived, to rise vertically or tilt, to have narrow or broad conduits, to have no plume head, a single head or multiple heads, to produce steady or variable flow, and to have high or low He3/He4. In stark contrast to the plate tectonic model, none of the original predictions of the plume model has been found to be true. What observations could conceivably cause the plume hypothesis to be rejected? If the answer is “none” then it is not a hypothesis, but a data-independent, a priori assumption

and this:

Significant, fundamental advances can be made only if new theories are applied and tested, rather than old ones progressively elaborated to match each new observation.

Sounds familiar, doesn’t it? If only the climate “debate” could be like that and focus on science.
What upsets me about the original article, to go back to it, is that the authors don’t seem to produce any observations showing more melting in the central Greenland ice cap than at the northern and southern ends. They have a model and that’s it. They don’t appear to actually have any heat flow measurements either. It’s just modelling again. Nothing wrong with models if they are related to observations, which doesn’t seem to be the case here. It’s a good idea, worth checking, but surely they could have found some data to support it.

Steve Case
April 6, 2016 5:55 am

Off Topic:
NASA has a new Sea Level web page:

Reply to  Steve Case
April 6, 2016 7:31 am

I noticed a mistake in one of the paragraphs on the NASA sea level web page.
“Today these mathematical chains of computer code provide representations of critical climate processes—the atmosphere, ice and oceans—across timescales, with increasing sophistication and accuracy. Modeling ensembles, such as the Coupled Model Intercomparison Project (CMIP), grow ever closer to the goal of interlinking disparate models to simulate the entire climate system [Flato et al., 2013, Edwards et al., 2010].”
It appears that replacing the word “disparate” with “desperate” in describing the models would have resulted in a more accurate statement.

April 6, 2016 6:23 am

But there just a bunch of geologists. What do they know about climate and ice?
It’s not like geologists were studying these things for decades…. lol

April 6, 2016 6:26 am

You get comments from people sometimes who seem to think that the total mass of ice in Greenland or Antarctica has something to do with climate. This is a strange delusion – it really does not. It is geology and tectonics / volcanism that determine the interaction of the bottom of thick ice sheets with underlying rock. Climate, on the other hand, is what happens on the surface where people live. Duh!

GP Hanner
Reply to  belousov
April 6, 2016 6:32 am

Aaaaand, there is significant vulcanism beneath Antarctica.

Reply to  belousov
April 6, 2016 7:47 am

You get comments from people sometimes who seem to think that the total mass of ice in Greenland or Antarctica has something to do with climate.

They will take anything that seems to prove CAGW.
On the other hand, the ice doesn’t ooze out of the ground. The climate is responsible for the fact that the ice is there in the first place. So, yes, the total mass of ice in Greenland and Antarctica has a lot to do with climate.

Reply to  belousov
April 6, 2016 9:15 am

You are right – I didn’t phrase that very well. What I meant was, for instance in Antarctica, if the air temperatures are staying the same or cooling, if the southern ocean temperatures are cooling, and if sea ice around Antarctica is growing, then the warming story cant be rescued by just saying “Oh but the mass / volume is decreasing so it must be warming”. Likewise for Greenland.
Cold climate is needed for there to be polar ice. But things other than climate can influence the depth and volume of ice sheets – such as volcanos underneath them.
I also have my doubts as to the reliability of the GRACE estimates of ice thickness and volume. If all they have in Antarctica or Greenland is GRACE numbers indicating loss of ice volume, this is a very thin fig leaf for the warmists in the context of cooling in the actual climate as experienced on the surface.

Reply to  belousov
April 6, 2016 9:54 am

GRACE only provides data concerning the earth’s gravitational field.
The data is then placed under a magic hat along with the Glacial Isostatic Adjustment models (invented by the minds of men) and the “estimates of ice thickness” is finally pulled from the hat. Ta-dah…
But, imagine that all we knew about Antartica was that both GRACE and altimeters showed a perfectly static unchanging situation. We could conjure up melting simply by inserting a melting favourable GIA estimate.
i.e with a will to discover melting, then melting can be discovered. Whatever the data says.
Along similar lines:
“Understanding the controversy also leads quickly into complicated problems of glacial isostatic adjustments to gravity surveys (GRACE), as the size of these adjustments turns out to be more or less equivalent to the size of the mass loss itself – hardly a desirable property of the method.”
Recommended reading here:

Reply to  belousov
April 6, 2016 1:51 pm

Thanks – useful insight.

April 6, 2016 6:42 am

and maybe El Nino?

April 6, 2016 6:46 am

I thought there was another study of elevated heat and subsea volcanic activity north of Iceland (?). That would make it more of a triangle shaped lithosphere anomaly involving Greenland.

April 6, 2016 6:48 am

We need a magma tax to go with a carbon tax. I’m sure we can find a use for all the cash hoard.

Jim G1
April 6, 2016 6:56 am

Geothermal, the other heat source left out of climate science and the only other source of energy besides the big yellow thing in the sky. But neither one is significant in climate compared to the .04% of our atmosphere composed of CO2. Besides, out of sight out of mind since the oceans cover 70% of the earth’s surface and have such an unkown effect upon climate and weather of all types. Makes perfect sense if you are an idiot.

Reply to  Jim G1
April 6, 2016 9:08 am

Preach brother! Been saying this for years now! Hot sea beds release CO2, warm gases move upward warming water as it goes, escapes the surface and enters the atmosphere. 24/7.
But the same people who agree that we have not mapped the ocean floors and have very little data regarding what happens at depth ASSURE ME that whatever volcanic activity/geothernal venting that occurs down there is insignificant…So small that the “consensus” is that it has no impact on our climate.
Which COULD only make sense to an idiot!

Reply to  Aphan
April 6, 2016 10:21 am

Aphan, what you don’t know can’t hurt you. Better still, what you don’t know can’t be used to prove me wrong!

April 6, 2016 6:58 am

Recently on several articles on WUWT I have brought this very issue up concerning heat from below rather than above.. nice to see someone is bothering to research this in more depth, this is not the only location, the Antarctic is seeing some of this action too, we literally have no idea of the amount of energy that is released from below into the oceans. Some mention 25% of heat in the oceanic crusts is carried away by convection, but it’s a huge guesstimate.
Crust convection contributes significant heat to oceans, it’s about time someone started quantifying it.
Any measurement of ocean temp at significant depth is useless unless the sources can be quantified. As is the climate warm leaning scientists don’t pay the issue it’s due.
Ocean crust convection probably plays more than a little part on ocean alkalinity.

Reply to  Mark
April 6, 2016 7:24 am

Nobody knows what the ocean is doing below 2,000 m which is half of it. The volcanic portion of the global heat balance is dismissed as trivial, but that’s terrestrial volcanism. Nobody knows how much heat and CO2 is produced at the ocean floor.

Reply to  Nicholas Schroeder
April 6, 2016 8:12 am

Exactly Nicholas, and seeing that is not quantifiable as technological and cost things stand, they ignore it, like natural sources of CO2 and any influence from outside of our atmosphere.
The IPCC have created a closed system with an unknown number of inputs missing. All too often theories are made from mathematics, with no physical bearing on reality

Reply to  Nicholas Schroeder
April 6, 2016 9:13 am

I seem to recall that some years ago it was finally conceded that the deep ocean vents provided energy to biota that out weighed all the rest of the photosynthetic dependent life on the planet. That would seem to indicate that there is a great deal about the energy cycles on the planet that we know next to nothing about including the contribution of the fission reactor that we all walk around on everyday.

April 6, 2016 7:02 am

Hobbits driving SUVs.

April 6, 2016 7:02 am

Can’t see how this adds much to the debate.
lts something that’s been going on for a long time and so has been a constant over the climate passed.
lts as if it has just turned up recently. What’s far more important is what is happening to the weather over Greenland over the long term. As l now understand the reason for the large swings in temps across Greenland during the ice age. This was due to the formation of huge Omega blocks forming over the North Atlantic and pushing up into Greenland. Driving warm moist air from the mid Atlantic air into Greenland, While at the same time areas of low pressure over NE America and northern europe were dumping large amounts of snow. Building up the ice sheets. What was going on at the bottom of the Greenland ice sheets matters little if its been a constant over many years..

Reply to  taxed
April 6, 2016 7:26 am

taxed, I agree. This is important for our wider understanding, but does not seem to directly affect the debate about changes to and caused by climate in the recent past.

Reply to  seaice1
April 6, 2016 7:57 am

This weather pattern matters a great deal to the current climate. Because lucky for us it does not turn up too often. But if this weather pattern becomes extreme in its persistence over a long time. Then the ice ages shows what it can do to the climates of North America and northern europe.

Reply to  seaice1
April 6, 2016 8:16 am

Actually if you are going to use any ice sheet as a metric in climate change, then yes this is relevant, it is also relevant to the waters in that region which is also relevant to the subject given almost all of Greenland’s melting is on the coasts.
While it does not relate to scientific discussions of particular research, it certainly matters when the cries of “long term records tell us of doom” are bandied about, by pretty much all media and people like Gore and Obama and every other idiotic scientifically illiterate politician and reporter

Reply to  taxed
April 6, 2016 9:25 am

Logical conclusion #1-If the article is correct, and this phenomenon has not been studied or well understood in the past, then current models and knowledge about this region cannot possibly have incorporated these dynamics prior.
Logical conclusion #2- if this process is just NOW coming to light, there is no rational way to even begin to conclude that it has been a “constant” over climate passed! Anyone with any degree of understanding about geological movements and geothermal/volcanic activity knows that in active areas, it is rarely, if ever, “constant”! Differences in the makeup of the lithosphere, tectonics, changing internal pressures in the convective mantle as different weights of land and ice masses move across volcanic zones etc,
If you think that what happens beneath the ocean surface has no impact on our atmosphere or climate, you are sadly misinformed.

Reply to  Aphan
April 6, 2016 10:08 am

You are talking about changes that take place over millions of years, not what happens over 10’s or 100’s of years.

Reply to  taxed
April 6, 2016 9:07 pm

taxed – clearly it has been going on for eons however we know very very little about the variability of the heat flux over time. Clearly these things change quite rapidly sometimes, like when an apparently dormant volcano suddenly erupts. we have a poor understanding the the actual heat flow from the interior, in parts of the USA the heat flow from the interior reaches 20Wm-2 and we do not have any idea what the average heat flow is under the oceans nor how it varies with time. A few years ago there it was suggested that changes in cosmic neutrino fluxes could alter the rates of radioactive decay and these changes could happen suddenly so the rate of heat generation internally might vary significantly on short time scales. Just another of the great unknowns that the ‘modellers’ just assume away.

April 6, 2016 7:03 am

“Past” not “Passed” 🙂

April 6, 2016 7:20 am

Why should Climate Scientists™ get all the money? Geologists want to get in on it, too. Every discipline should be creating their Big Scare.

Reply to  Gamecock
April 6, 2016 2:32 pm

The Yosemite caldera doesn’t qualify? Super volcanoes are a better story than CO2 induced AGW/ACC, even if they’re actually real.

Reply to  Gamecock
April 6, 2016 3:02 pm

Apologies, Yellowstone caldera.

Reply to  Gamecock
April 7, 2016 10:20 am

Palaeoclimate history of rock units is a major aspect of terrestrial and marine geology interpretation and mapping. It always has been, and always will be.
The atmosphere and water all came from rock and mantle, not from space, and the resulting climate is the result of the evolving geological processes, and the orbit and the star.
Understanding the interaction of ice, water and rock is critical to the interpretation of much of geological history. Almost all of the pioneering work on glaciers and icesheets was done by geologists, as they were the first people mapping and surveying everywhere the planet in detail, climbing every mountain they could get to, to get samples and map it all. Same for the characterization of global climate through time, it is implicitly a major geological field of research.
It is the reason why glacial to intergalacial cycles and Milankovitch cycles became understood as the major climate drivers, and how ocean and continent arrangements and depth changed climate as well.
It’s not a scam and it’s not new wither, it’s what we’ve been systematically doing for well over a century, and it is at the core of geology as a science, and the very means of how so much human discovery has already taken place.
It’s why there’s even a climate debate occurring right now.
No tell me, if there’s widespread volcanic and hydrothermal activity going on under ice sheets everywhere (and there is, lots of it) who would you have researching that? Someone who has been studying this entire domain of knowledge or earth all their career, or someone who plays with computer models, shuffles papers, and occasionally goes on field-trips with a pith helmet and a website, replete with press release updates and a camera crew sponsored by big-fruit computer corp, and makes a circus out of the pretense of being ‘scientific’ for a week or two, of rank ineptitude, confusion, ignorance, overreaction, incompetence and international melodramas?
Geos just get on with the job like they always have, we’ve been doing that all along, we never stopped at any point, we were doing long before anyone else was doing it, and we’ll still be doing it after their hype-funding spigot runs dry.
It’s also why geologists were sent to the moon, at great expense and danger, to collect samples, as they were the only ones who knew sh*t about any of this stuff, they would notice all the right things, they would ask the valid questions, and identify the key scientific clues and characterize them properly. And if humans go to Mars the first scientists there will be geologists again.
Lump us in with the climate-fraudsters and pseudo-scientists would you?

April 6, 2016 7:21 am

So where will a glacier melt? At the air interface where it’s -20C or the ground interface where it’s 5C? Hmmmm, a real poser.

Reply to  Nicholas Schroeder
April 6, 2016 7:38 am

lt matters little if there is melting at the bottom of the ice sheet if its been more then been replaced by snowfall on top of the ice sheet. This blocking pattern will have been sending warm moist air up over Greenland in large amounts. lt would have warmed Greenland up but it still would have been well below 0c over most of Greenland. But with this warmer moist air there would have been a increase in snowfall over Greenland. Hence the reason why the ice sheets were still able to expand over Greenland. But this is a bit of a side issue. The more important part is the effects this Omega blocking had on the climates of North America and northern europe.

Reply to  taxed
April 6, 2016 8:12 am

Sorry one too many “been” in my first sentence.

Reply to  taxed
April 6, 2016 9:39 am

It matters a h@!# of a lot because that bottom melt is what lubricates that ice sheet and causes it to slide from the summit to the ocean. More snow forming ice at the summit. More ice=more weight. More weight= faster sliding. More sliding=more ice mass called into the oceans.
Mass lost is mass lost. It doesn’t matter whether the mass it’s losing is on top or on bottom, but the mass it loses from beneath is just now beginning to be understood. But this understanding is a major hit to the CO2/CAGW argument because this demonstrates a formerly unknown, unqualified, NATURAL reason that is causing the Greenland ice sheet to be unstable and lose mass that has zero to do with the climate above it.

Reply to  taxed
April 6, 2016 10:03 am

The Greenland ice sheets can’t be all that unstable, as they have managed to last through out the current warm period. Thanks to the shape of Greenland’s landscape. Also if the more snow that falls on Greenland is matched by the ice loss, then at some point they will be in balance. As l say l don’t think this is a big issue.

Ian W
Reply to  taxed
April 6, 2016 2:46 pm

Taxed, logically it is not a big issue. Nor is the West Antarctic Ice Sheet which has similar geothermal heating causing some break up, nor does the waxing and waning of Arctic ice have any real meaning. But for the scientifically and geologically illiterate politicians they can claim that all those ‘melts’ are caused by anthropogenic CO2 and therefore close down all the ‘fossil fuel’ generating capacity in the first world and tax industries into oblivion and have those in energy poverty freeze to death each winter. Whether you feel it is illogical or not, the politicians are using the claimed ‘recent’ melting of the ice as all due to ‘climate change’ caused by the cancer on the Earth humans and their use of fossil fuels.

Reply to  taxed
April 6, 2016 4:42 pm

“You are talking about changes that take place over millions of years, not what happens over 10’s or 100’s of years.”
Am I? How strange. I thought I was talking about volcanic/geologically active areas and how fast they can “change” certain conditions without notice. You know, since the thread is about subglacial melting due to underground heat sources…
“The Greenland ice sheets can’t be all that unstable, as they have managed to last through out the current warm period. ”
Yes they have, but it’s the warmists that are claiming that they are unstable, not me. But they DO sit on one of the most geologically active regions in the world. And we all know how predictable and dependably stable areas like that are…right?
(from the article) “The movement of the Jacobshavn Glacier in the Jacobshavn Valley is of great interest. NASA’s Study shows that this glacier was flowing very slowly down the valley and at the same time started gaining ice mass until 1998. At that point, it quickly started flowing down the valley while simultaneously losing large amounts of ice mass.”
I don’t know about you, but I read that as sounding like something changed in a drastic manner in 1998, and it didn’t take millions, or hundreds of years, or even 10’s of years to manifest.
More from the article-
“The recent discovery of two Sub-Glacial Freshwater Lakes beneath the Greenland Continental Ice Sheet is highly significant.
Although not interpreted as being related to geothermal heat by the authors, it is clear that geothermal heat is the most likely cause. The two lakes are located in the north central portion of Greenland beneath 1500 feet of ice and 30 miles from the ice-free edge”
I guess maybe your Omega blocks have the ability to crawl under the ice caps and affect long term melting and erosion processes, but what do I know? Seems to me like those Omega blocks of warm air are considered “weather patterns” rather than climate changes, although the jet stream is affected by sea surface temperature changes…maybe even large, sudden…”eruptive” changes? http://www.livescience.com/45415-greenland-warming-partial-natural-cause.html
In 1996, the Grímsvötn caldera erupted, melted 3 cubic kilometers of ice and caused an enormous glacial lake outburst flood. Fast change. Not millennial.

Samuel C Cogar
Reply to  taxed
April 7, 2016 3:50 am

Aphan said: April 6, 2016 at 4:42 pm

More from the article-

“The recent discovery of two Sub-Glacial Freshwater Lakes beneath the Greenland Continental Ice Sheet is highly significant.
Although not interpreted as being related to geothermal heat by the authors, it is clear that geothermal heat is the most likely cause. The two lakes are located in the north central portion of Greenland beneath 1500 feet of ice and 30 miles from the ice-free edge”

I guess maybe your Omega blocks have the ability to crawl under the ice caps and affect long term melting and erosion processes, but what do I know?

Iffen the earth experiences another extreme warming period such as the Holocene Maximum …. and all of the glacial ice on Greenland AGAIN melts off leaving per se “bare” ground, ……… would not those two Sub-Glacial Freshwater Lakes have to be reclassified as being just plain ole freshwater surface lakes?
Me thinks those 2 freshwater surface lakes existed prior to any glacier formation.

Ian H
April 6, 2016 7:43 am

I didn’t think Mantle plumes were quite that big. I always think of plumes in terms of localised hot spots. If there is a plume under Iceland, which is debatable, it would need to be a pretty darned big plume to extend under Greenland.

Reply to  Ian H
April 6, 2016 8:20 am

While the actual hotspots tend to be not that big, the pressure at depth keeps water from boiling and what you have are small vents with large areas of water at temps like 400c – 500c and maybe above as water cannot boil when pressured at depths. They act like large radiators above the ocean floor.

Reply to  Mark
April 6, 2016 9:01 am

Sounds like a great geothermal renewable idea to sell the alarmists. They should love the concept of cheap infinite, (to a human) energy for housing.
Of course, any direct heating from a mantle plume likely contains massive amounts of pressurized CO2, especially if the plume passes through or resides in carbonate sediments.

Reply to  Mark
April 6, 2016 10:01 am

But heat convects and rises. That’s why the geothermal activity from beneath the surface of Greenland can reach the surface to melt the bottom of the glacier. Heat under pressure in the oceans at depth is no different than heat under pressure under a landmass, except that heat can move through liquid much faster. It dissipates into the water column above and around it.
What could heat deep ocean waters more effectively…radiation from the Sun which can only penetrate a few hundred feet on a perfectly cloudless day at max power for a few hours (directly overhead) at nowhere near boiling temperatures while competing with wind, surf, evaporation and conduction and convection of the atmosphere…or heat plumes in the Ring of Fire producing super heated water, crust, magma, black smokers, volcanic eruptions, 24 hours a day every day? Water so hot, land and minerals so hot, and under so much pressure that they can literally grow new landmasses so large that they reach the surface and provide real estate for millions of people live on? AND continue to grow after that?
Nah…..silly little hotspots….nothing to see there folks…

Reply to  Ian H
April 6, 2016 3:49 pm

The plume under Iceland is supposedly 100 miles wide and 370 miles deep according to this video-https://www.youtube.com/watch?v=jZdeavURhk8
Iceland sits the rift between the Eurasian Tectonic Plate and the North American Plate. The Atlantic Mid Ocean Ridge actually rises above sea level and cuts right across the middle of Iceland. Its one of the most geologically active areas on the planet.

April 6, 2016 7:45 am

Money quote: “This, in turn, broadly influences the dynamic behaviour of ice masses and must be included in studies of the future response to climate change.”

Tom Halla
April 6, 2016 8:24 am

OMG! Volcanic activity under Greenland! We must find a virgin to throw in the volcano to appease the Gods! Mother Gaia is upset so we must raise taxes! /sarc

April 6, 2016 8:31 am

It would be interesting to see a melt map for a year and see how much of the melt occurs in the regions overtop the plume.

April 6, 2016 8:51 am

The physics of the earth and melting *requires* that the temperature at the bottom of a glacier is at or below 0° C. The earth’s mantle is hotter than the surface – everywhere. That heat is conducted from the warm mantle to the cooler surface (Newton’s Law of Cooling). When the heat encounters ice at the surface, as at the bottom of a glacier, it keeps on flowing until the ice in contact with the surface is melted (at 0 °C). The melt water then flows downhill, exposing more ice to the geothermal heat. The thin layer of water trapped between the ice and the ground acts as a lubricant, especially under the pressure of the overlying ice, and facilitates the downhill flow of the ice.
I project that if one were to measure the temperature at the ice-ground interface of a glacier, it would fall exactly on the melting point for ice at that pressure. See the phase diagram for water: http://www1.lsbu.ac.uk/water/water_phase_diagram.html

April 6, 2016 9:29 am

Anthony, your blogs scare me to death – I am really worried now – we are doomed – there is no way to escape global warming it seems. Except perhaps if we all move to the moon or to Mars en bloc. That to me is our only hope.

Reply to  AndyE
April 6, 2016 9:41 am

Please don’t. The truth is that there is nothing to fear from global warming. We are looking at mild changes from a slightly warmer planet. There is literally nothing to run away from.
Seriously, what do you think will happen from temperatures 2-4C warming (concentrated at the poles) and with slightly increased rainfall? What will actually happen? The answer is simply, not much. There will be some notable shifts, such as a few rivers not freezing over (we’ve already seen the end of Thames ice parties since the end of the Little Ice Age), and probably a few record highs, but that’s pretty much it. The natural variation is so much larger than the effect that it will be difficult to tell the difference except in the aggregate.

Reply to  AndyE
April 6, 2016 10:37 am

Why must we escape global warming? It’s so much better than global cooling! We can grow more food, live longer, healthier lives, and do pretty much everything we do today BECAUSE the world got warmer, had an interglacial period, during the time of humans. How lucky are we?
The oceans have been much higher than they are today! And could very well be that high again. We’ll manage. We’ll adapt. It’s the nature of things. Of course SOME of us aren’t evolved enough to stop building cities on fault lines, or right up against the oceans and cliffs, or in tornado alleys. But evolution and Mother Nature work together to thin the herd, add Clorox to the gene pool.
The sad part is the stupid humans eagerly buy into the pitch that other humans are smart enough and powerful enough and strong enough to actually control or counteract the forces of nature. Like Earth is just a really big, dumb animal that they can break and rule over. They tell silly believers terrible stories about this beast, her cruel appetites, her temperamental ways, her future attacks, and then, when they have the crowd in a frenzy….they cry “But we can stop her! We are scientists AND superheros! Silence our composers and give us money and we will save you!”
Yawn. They can’t. How can they save us from something THEY don’t even fully KNOW yet? That THEY haven’t fully explored yet? That THEY can’t even begin to mimic or model accurately yet?
It’s like pretending that if we could keep a human’s body temperature at a perfect and constant degree, that it would never experience any sickness, or trauma, or adverse changes of any kind afterwards. It would never vomit, or fall down, or rupture or move violently or abruptly. It would be perfectly safe and stable forever!
Any moron can see how stupid that idea is. And yet, aren’t they pretty much trying to get people to buy a similar notion? That if we could just keep Earth’s temperature from rising, it would prevent world hunger, wars, diseases, refugees, infertility, blindness, insanity, and curtail extreme weather events? That it would literally save the planet and mankind?
And people are buying it! How sad is that?

April 6, 2016 10:38 am

Climate alarmists have the same script: change everything, pay us money, or else the Planet is DOOMED!!! Geologists have a different way of doing things: explore, take samples, follow the facts, then report their findings. As luck would have it, the real scientists reach the opposite conclusion of the warmists. Are we surprised? *nope*

Reply to  momsaid2
April 6, 2016 11:24 am

It’s almost like climate alarmists want to separate what happens on land (and under the ocean) from the entire “climate system” in every possible way, and act as if the word “climate” only applies to the air and the sky above the surface! They often discredit or ignore the work of geologists and other “land based” scientists, and when push comes to shove they just say “Well he’s not a CLIMATE expert”.
But Earth’s systems are intricately intertwined, affect each other, and are necessary to the entire picture. When you ask a question about marine volcanic influence for example, and mention that today we have not been able to even identify each site, let alone measure or quantify their influence on the ocean, they’ll say “Well the numbers the experts use indicate that they have little to no effect upon….” Excuse me? So you admit that the “experts” haven’t found them all, and thus could not have measured their influence at all, but you are confident in their declarations that their effect is minimal? When did that become science? When did curiosity and investigation and measuring and detail stop being part of KNOWLEDGE?
It’s not just the disgraceful level of scholarship shown by certain “climate experts” that makes people doubt and mock them anymore. It’s the rising amount of serious, credible, and opposing work being done in other fields that they are so hostile against. Why would any real, serious, unbiased, credible scientist SHUN more information, no matter who brings it to the table?

April 6, 2016 1:04 pm

It sounds like there is a super volcano beneath the Greenland icecap – kind of like Yellowstone Park and the surrounding area under the ice. Sure hope it doesn’t BLOW, like Yellowstone has done in the past.

April 6, 2016 5:53 pm

Every now and then a very interesting explanation for phenomena comes along. You just have to recognise it when it arrives. This is one of tem. Thanks go to Irina Rogozhina, Alexey G. Petrunin, Alan P. M. Vaughan, Bernhard Steinberger, Jesse V. Johnson, Mikhail K. Kaban, Reinhard Calov, Florian Rickers, Maik Thomas and Ivan Koulakov

April 6, 2016 6:21 pm

Jules Verne knew all about this in 1864!!!

April 6, 2016 6:24 pm

All you need is a bit of Latin written backwards and we can crack all of Earth’s mysteries.

April 6, 2016 7:30 pm

Sounds like a good opportunity to do some real honest research. Bore a hole through the ice/snow on Greenland to the land/dirt surface. Measure the temperature gradient of the ice. Then bore through the earth surface (same hole) several thousand feet. Check that temperature gradient. Compare with temp gradients elsewhere ( e.g. oil drilling). Useful data could be collected.
At least the temp gradient in the ice/ice hole could offer a more reliable source of data than from water and air which is subject to conditions in constant flux. That could begin to offer some insight as to how much heat is actually transmitted from land and undersea surfaces. This would not even begin to cover open fissures but would be a start. Just stop pissing research $$$ away on CO2.

April 7, 2016 12:10 am

The weight of the ice sheet has also isostatically depressed the crust below, so the crust has thinned from below via crustal extension (moving apart in rifting), and also from above, via isostatic depression of the lower crustal hot rocks, deforming plastically and squishing and flow-deforming horizontally, away from the area under the ice.
Hence the margins of Greenland are relatively uplifted, trapping both the ice sheet, and the warmer water below it, within a deeper central basin’s depression).comment image
And hot shallow thinned rock over an elevated mantle often exhibits extensive hydrothermal systems exhaling super-heated water (black smoker like, or even geyser like, in an extending crustal basin) either from water re-circulation through crust and/or via ‘juvenile’ water from upper mantle melts dehydrating their waters as the melt cools and solidifies, donating it to the surface hydrosphere in the process.
The processes of earth are much more complicated than can justifiably be generalized into pat alleged ‘settled’-science narratives of suited clowns in Capital buildings and their out-houses.

Reply to  Unmentionable
April 7, 2016 12:56 am

Note: the Greenland lake is ~ the same shape & size of Britain inverted.

wayne Job
April 7, 2016 2:35 am

Not so long ago to their amazement the gurus of the standard model of the universe found 95% of it missing.
What is missing is dark energy, the energy that powers the universe and is the creative force, it circulates through the sun and the planets and keeps us warm from the inside. 4.5 billion years and the earth is not a solid dead rock but oozing with heat from the inside, this is our heat, the variations of this give us our warm periods, cold periods and ice ages because of variations in our relative position of our big planets and our place in our galaxy. This is a better explanation than CO2.

April 7, 2016 7:08 am

This shouldn’t come as a surprise. I dimly recall reading something long ago about a team that had rigged up all these cool remote sensing devices. They intended to toss them into a crevasse in the ice and hope to find some later to get readings on Greenland melt water. Their shipment of remote sensors got lost and their opportunity to get something into the melt water was slipping away so someone on the team bought a box full of rubber duckies. They threw them in. Some time later they were actually able to recover some and they had been melted.

Reply to  TomB
April 7, 2016 9:28 am

Did they write a paper about this?

Reply to  Unmentionable
April 7, 2016 11:55 am

Dunno. Perhaps you could google “Greenland rubber ducky” and find out.

James at 48
April 7, 2016 3:34 pm

Meanwhile, gotta love them sea ice bridges they get some winters. Icelanders don’t like it too much, though … Polar Bears take their vacations on the comparatively balmy Icelandic shores! 🙂

April 9, 2016 7:57 am

This is another fascinating study that will unfortunately be ignored by the mainstream media.

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