TOHOKU UNIVERSITY
A team of researchers understands more about the melting of the Greenland ice sheet. They discovered a flow of hot rocks, known as a mantle plume, rising from the core-mantle boundary beneath central Greenland that melts the ice from below.
The results of their two-part study were published in the Journal of Geophysical Research.
“Knowledge about the Greenland plume will bolster our understanding of volcanic activities in these regions and the problematic issue of global sea-level rising caused by the melting of the Greenland ice sheet,” said Dr. Genti Toyokuni, co-author of the studies.
The North Atlantic region is awash with geothermal activity. Iceland and Jan Mayen contain active volcanoes with their own distinct mantle plumes, whilst Svalbard – a Norwegian archipelago in the Arctic Ocean – is a geothermal area. However, the origin of these activities and their interconnectedness has largely been unexplored.
The research team discovered that the Greenland plume rose from the core-mantle boundary to the mantle transition zone beneath Greenland. The plume also has two branches in the lower mantle that feed into other plumes in the region, supplying heat to active regions in Iceland and Jan Mayen and the geothermal area in Svalbard.
Their findings were based on measurements of the 3-D seismic velocity structure of the crust and whole mantle beneath these regions. To obtain the measurements, they used seismic topography. Numerous seismic wave arrival times were inverted to obtain 3-D images of the underground structure. The method works similarly to a CT scan of the human body.
Toyokuni was able to utilize seismographs he installed on the Greenland ice sheet as part of the Greenland Ice Sheet Monitoring Network. Set up in 2009, the project sees the collaboration of researchers from 11 countries. The US-Japan joint team is primarily responsible for the construction and maintenance of the three seismic stations on the ice sheet.
Looking ahead, Toyokuni hopes to explore the thermal process in more detail. “This study revealed the larger picture, so examining the plumes at a more localized level will reveal more information.”
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It’s settled then?
Like all Science /s
right up to the moment that it isn’t.
Yes. Co2 causes mantle plumes in an as yet undiscovered way but it probably has something to do with feedback mechanisms where the warm exposed rocks reduce albedo which in turn exposes the land mass to increased radiative effects of the atmosphere thereby creating some kind of tipping point. I would not be surprised if excessive fishing from diesel powered boats was involved as well. 🙂
+1
I’m sure Trump’s policies and Brexit are both contributing to the plume’s heat.
Honestly, people, it’s puffin farts that triggered all of this. That’s totally settled science. What is interesting is all the down stream effects.
err, down mantle, I mean.
+1
Interesting! While I haven’t studied this phenomenon, I hadn’t heard that mantle plumes could be branched. It would be interesting to see research on other known hotspots to see if they exhibit similar branching.
Plenty under West Antarctica !
Yellowstone is a good example.
The 3D mapped deep magma chambers look similar to the casts made from large species of ant’s underground nests. People melt large quantities of aluminum and pour it in the surface entrance of the ant nest. It’s amazing to see how much of the molten aluminum goes in. Left for a day they are dug out and hosed of. They result … is an artwork of nature. Lots of videos about them on Youtube.
So what you’re saying, is that we have giant, underground, lava-living ants that are destroying our environment?
I find your theories intriguing and wish to subscribe to your newsletter!
Try this:
http://www.plateclimatology.com
Thanks for the link CB, cool stuff!
So the ice in Greenland melts from warming below, not from warming above.
“So the ice in Greenland melts from warming below”
No. Firstly the mantle configuration they describe has been there for many thousands of years, as has the ice. There is nothing to describe a cause for recent melting.
But anyway, the amount of heat that can diffuse to the surface (through km of ice) is far too low to supply the latent heat for the melting observed.
How it might have an effect, as in W Antarctica, is by softening the bottom of the ice layer, accelerating sliding resulting from surface warming.
Melting began in the period around 10 to 20 thousand years ago.
Nick, before you declare that the melting is coming from surface warming, don’t you need to actually demonstrate that there is surface warming?
And no, models aren’t proof.
“before you declare that the melting is coming from surface warming”
Surface melting requires heat. A lot of heat. And it can’t come from below. The reason is that it can only be conducted down a temperature gradient. But melting happens at the melting point. It can’t flow there from somewhere warmer through the ice. The ice has to be colder.
It can only come from above – ie the air.
air at negative XºC does not melt ice.
There are streams coming from UNDER the ice sheet.
so NOT from surface melt. !
Greenland Ice area is only a tiny amount down from its peak during the LIA, has been much less in the past 8000 years.
Greenland SMB was less during the 1930s, 40s than now
Because it was warmer
Once again, Nick demonstrates a complete inability to actually read what he responds to.
I said nothing about heat coming from below.
Your comment about it taking a lot of heat to melt ice is absolutely true, too bad I said nothing about how much heat it would take to melt ice.
What I asked for was evidence that Greenland had gotten warmer.
Beyond that it would be nice if you could demonstrate that this warming, if it exists, is caused by CO2.
“Surface melting requires heat. A lot of heat.”
Which Greenland very rarely gets. !
Thanks for pointing that out, Nick 🙂
“What I asked for was evidence that Greenland had gotten warmer.”
IPCC provided that….
oh…… OOPs !
Try again
Ice can also sublime into the air if it is not saturated. Wind doesn’t have to be above freezing point to cause ice ablation.
Yey. I got to out-pedant Nick Stokes.
Hmm. All the replies to you, Nick, seem to contain … facts.
Dreadful. Ain’t facts a b****r?
WOW,
that logic sounds very familiar…
where have I read about “The reason is that it can only be conducted down a temperature gradient…” before.
😉
“There is nothing to describe a cause for recent melting”
Variable magma flow comes to mind. What evidence do you have that the mantle configuration is steady state?
“But anyway, the amount of heat that can diffuse to the surface (through km of ice) is far too low to supply the latent heat for the melting observed.”
Geothermal heat melts ice from the bottom of the ice cap, not the top. There are no km of ice to diffuse through.
“What evidence do you have that the mantle configuration is steady state?”
With regular volcanic eruptions around the Iceland area…
….. we can be pretty darn sure that it most certainly ISN’T stable !!
I make no claims about Greenland or any other particular place but simply point out that mantle plumes, and other volcanoes, are know to have widely varying outputs, some semi-regular (Yellowstone). Something that has been inactive for thousands of years, or more, does become much more active upon occasion, for reasons not understood by humans.
The bottom of the glaciers for much of Greenland are actually below sea level, there is no sliding to the sea resulting from this warming.
Hush, MarkW, never interrupt an expert with inconvenient truths when he is working.
No, the magma chambers existence is not the only factor in convective ground heating capacity, it is the amount, type, and even more so the movement of fresh hot magma into the magma chambers. How do you know what is going on under the Greenland ice sheet, or the Antarctic Ice sheets ? Both have substantial volcanic sources.
And, heat does not diffuse through ice to the surface, the heat melts water first. That water under pressure creates lakes and rivers under the ice.
Surface warming is also called by another name … summer.
“Both have substantial volcanic sources.”
Sender: Both also have sub-marine volcanoes offshore. Iceland itself is solely made up of lava flows. Strange they didn’t mention the action of plate tectonics, a split in the ocean floor from north of Iceland all the way down to the South Atlantic which causes oceanic floor spreading and volcanic activity (Iceland, Azores, etc.).
It is virtually certain that proximal sea floor volcanoes off Greenland to the southeast and West Antarctica are promoted by the weight of the ice sheets themselves which redirects the flow of magma, to some extent to the periphery of the ice areas. Iceland’s formation would have been helped by suppression of lava flows to the north under heavy ice of the glacial maximum.
Volcanic intrusion into the ice below West Antarctica was detected seismically in 2015 (?) by US geophysicists who were taken by surprise by the event. The hype and predictions of disaster from CO2 warming melting ice sheets there quietened down a lot thereafter, although the whole area was known to be active volcanically for a century.
Nick Stokes, they show a picture and caption it that their solar panels are buried in ~ 1.5 meters of snow in one year. Melting from above? Try another guess.
Recall also the three P-38s that emergency landed on central Greenland during WWII. A group went to find them and maybe fly them home. They found them using geophysics to be buried 200 ft or so in the ice! They excavated one, rebuilt it and flew it at some air shows.
That experiment tells me the ice sheet is going to be around a lot longer than the concensus ‘climate wroughters’ think! Things like this, detecting recent lava intrusions into the base of the W. Antarctic ice sheet, the two decade pause in temperature rise globally must make life tough for climate consensus wives and small pets.
So, when did you get a degree in vocology or become a Volcanologist? Even a basic course in geology informs you that there is little predictability or regularity about volcanos. They are not like “Old Faithful,” which I know is not a volcano and is not as constant as it once was. Meaning Things Change!
Yellowstone is a caldera, which is another word for a really big volcano.
No, a caldera is not a really big volcano. A caldera is a really big depression left when the ceiling of a magma chamber collapses after the chamber empties in a massive eruption.
Instead of a cinder cone, really big volcanoes form calderas.
Oh look, Nick putting his leftist spin to make something relevant, irrelevant.
Magma plumes from below are just a bit warmer than the atmosphere. Physics 101 Nick.
There is no recent melting, huge gain last year!
H/T to Fred250:
http://polarportal.dk/fileadmin/polarportal/surface/SMB_curves_LA_EN_20201207.png
“huge gain last year”
That is not what it shows at all. You’re probaly confusing Surface Mass Balance, which is surface melt vs snowfall, with Total Mass Balance, which includes calving icebergs. However, both the surface and the total lost mass last year.
http://polarportal.dk/en/greenland/mass-and-height-change/
ROFLMAO..
and little loy-dumb goes straight to gravity based data
DUMB !!
Obviously hasn’t read anything.. or is totally lacking any basic comprehension.
Also didn’t see the little words down the bottom
August 2020, relative to APRIL 2002.
An meaningless graph from a meaningless little troll.
So WRONG again, loy…..
There was surface mass gain last year..
Must have been caused by human atmospheric CO2 , hey ! 😉
As for the “mass change” .. even by the gravity based farce.. it looks like this since 1900.
A meaningless small change,
Did you know the actual Greenland Ice area is WELL ABOVE the 8000+ year area.
Only a tiny amount down from the peak area in the LIA .
As for calving.. you do know that is a totally natural thing for rivers of ice do, don’t you !!
Or does your ignorance continue unabated.
I know reading graphs is one of your many incompetences., loy
But ANYONE can see the SMB was around 350 Gt from September to August last year
polarportal.dk/fileadmin/polarportal/surface/SMB_curves_LA_EN_20201207.png
Please keep showing everyone your incompetence at basic graph reading. 🙂
How does surface warming manage to heat the bottom of km of ice layers and accelerate sliding? Does it work only one way?
” There is nothing to describe a cause for recent melting.”
Are you saying the melting is unprecedented? If so, well, really
Proper science.
we will need to fund a project to dig some wells so we can cool down these hot spots
and prevent sea level rise
Does this mean that Climate Change has nothing to do with Greenland actual melting? Just have to blame the volcanic plume. Now to stop the heat from below, lets stuff IPCC faulty paperwork in the hole for all they are worth.
They have known about the geothermal activity under Greenland for ages.
IIRC, the magma plume is actually part of the rather active Icelandic volcanic system.
One of the reason that gravity based ice measurements over Greenland are basically pointless.
Thank you. I had a feeling reading this that it was an article about nothing meant, to justify why Dr.Toyokuni wasted his summer up there.
More info here
https://tambonthongchai.com/2020/10/30/the-greenland-iceland-mantle-plume/
There are also significant volcanic tracks across the north Canadian/Greenland region
https://www.bgr.bund.de/EN/Themen/Polarforschung/Projekte/Arktis_abgeschlossen/vulkanismus_en.html?nn=1552422
They used seismic tomography, not topography.
You say tomography, I say topography, let’s call the whole thing off.
Indeed. No idea what seismic topography is. Seismic tomography is a well-known technique for estimating a 3D velocity field from first arrival times.
Chinese whispers from the researchers to the press release to Eurekalert?
These fellows seem more focused on measurements, whereas the 2013 study WUWT:”Surprise: Greenland ice gets a melt assist from Earth’s hot mantle below” is more babbling about models.
The main shift in theory between the German 2013 and this team, appear to be that the 2013 team assumed the lithosphere is extremely thin, whereas the new team assumes the plume has branches in the lower mantle that feed into other plumes in the region
I miss a nice drawing like the one Anthony put on the 2013 thing.
The year to year variability that mantle plums are known to under go make a total hash of any attempts to use gravity to measure the size of the Greenland ice cap.
“The year to year variability that mantle plums are known to under go…”
What are you basing this on?
On real evidence..
You should try it some day !!
Do you REALLY think that magma flows are constant, never-changing entities !
REALLY ! ????
News for loy
Not only do flow rates vary significantly, the chemical content also varies considerable hence so does density and ferric composition ie magnetic fields
These HUGE moving sacks of variable content and density make the gravity quite variable over moving magma sacks.
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2011GC003748
Now, instead of asking inane questions, how about you try to do some basic learning before posting.
Thanks for your link to “Compositional trends of Icelandic basalts”, while interesting its completely irrelevant. No, I’m asking Mark about “year to year variability” of mantle plumes. I doubt he’ll show me what he based his comment on because… now I’m taking a stab in the dark here… but Make-it-up Mark probably just, um well, made it up.
The point is of course that this ‘new’ mantle plume has probably been there longer than Greenland has and hasn’t changed in a million years. And so I wonder why WUWT wants to doubt-monger about mantle plumes, mmm I wonder.
“while interesting its completely irrelevant.”
No its just that you are too lacking in any understanding of anything
Composition effects density. effects gravitational pull
Of course the magma is totally static.. …
… that’s what magma does.. stays still.. right loy-dope !! roflmao !!
Try to keep displaying your total ignorance in EVERY post you make, loy-dope !
Hint, little -nil-educated child
“Magma plumes are areas of hot, upwelling mantle.
Role of mantle plume in plate tectonics: The narrow conduits of deep-mantle material rise through the solid mantle before spreading out laterally in the upper asthenosphere. From there, they cause the lithosphere to swell and shear as the heat from the plume increases the temperature of lower lithosphere.
Do…
you…
under…
stand !!!!!
I see that Loydo not only can’t defend his position, he isn’t even smart enough to bail while behind.
If you half as much as you believe you do, you would know the answer to that already.
I’m guessing that you actually believe that the magma in these pipes and chambers just sits there and doens’t move around.
Interesting that some of the melting of the Greenland ice sheet may be due to heat from below (which is likely a greater effect than any warming from above, since temperatures at the top of the ice sheet are rarely above freezing).
Geothermal heat could eventually melt enough ice to form one or more lakes below the ice sheet, but this would only affect the top of the ice sheet if the lake(s) were deep enough to float the ice sheet off the bedrock below. The ice sheet is also locked in place by the mountains near the coasts of Greenland, preventing most of the ice from sliding into the sea.
The caption to the photo also reveals why it will take an extremely long time for any appreciable melting of the Greenland ice sheet, if it receives 1.5 meters of snow per year. Distributed over 1.71 million km2 of area of the ice sheet, this would result in a volume of about 2,560 km3 of snow per year, or about 0.09% of the total volume the ice sheet, and fresh snow has a higher albedo than ice.
Global-warming alarmists are fond of pictures of icebergs calving into the sea, but that mostly takes place on south-facing edges of the ice cap, which receive the most direct summer sunlight. Inland areas of the surface of the ice cap (at high altitude) are below freezing year-round, and there are few observers for the winter blizzards which mostly occur during the long, dark polar night.
“Geothermal heat could eventually melt enough ice to form one or more lakes below the ice sheet, “
There are already many such lakes known under the Greenland Ice sheet.
https://www.smithsonianmag.com/smart-news/more-50-lakes-found-under-greenlands-ice-180972509/
The PV system isn’t buried in snow in the photograph: backs of two rack-mounted modules are visible on the left (the dark rectangles are junction boxes for the wiring). What is under snow is likely the battery plus the instrumentation package. Remote power is an application for which PV excels.
I strongly doubt that the Greenland Mantle Plume is caused by mankind’s burning of fossil fuels. What effort will be required to stop the plume from melting ice in Greenland and how much will it cost?
William Haas: Somewhat less than installing a second sun so we can have solar power at night. 😁
Geothermal heat, the only other true source of heat other than solar, is a large unknown and rarely discussed. Good to see it discussed here. And yes, I know it gets covered here now and again but as I said little is really known, data wise and it may be a larger player in climate than we presently know.
I am still intrigued by the correlation between ocean seismic activity, lagged 2 years, and atmospheric temperature.
Ocean seismic activity started to fall about 2-3 years ago.
Will be very interesting to see if temperatures also start to fall.
(They may start to fall anyway due to the AMO and PDO cycles)
….. but still, an interesting correlation.
Greenland is so cold every snowflake that falls outside the melt season sticks. There is no melting on top when the cold sets in.
What matters most on mass gain is the amount of heavy snow events that cross over the island each year. Some years the Greenland high sets up and blocks these lows and some years the lows pass over frequently. As the weather is all interconnected El Niño’s and La Niña’s effect ice gain. Ice melt is one half the equation.
Current Greenland SMB is basically on the average of the warming from the cooler period starting around 1981
polarportal.dk/fileadmin/polarportal/surface/SMB_curves_LA_EN_20201207.png
It’s not new
http://www.geo.uu.nl/Research/Seismology/pdf/ngeo2689.pdf
Nature geoschience 2016
Melting at the base of the Greenland ice sheet explained by Iceland hotspot history
Must be where one of the the maps I posted earlier came from..
Thanks, I’ve been looking for that.
It’s not new
It is to the BBC…
…Scientists say this confirms Greenland ran over a hotspot of upwelling molten rock tens of millions of years ago as it shifted towards the Arctic.
It’s like the underside of the island got a good roasting in the distant past and still has the big scar to prove it.
https://www.bbc.co.uk/news/science-environment-45031592
That was 2 years after your link was published.
It’s how you spin it that counts.
https://www.researchgate.net/publication/322642527_High_geothermal_heat_flux_in_close_proximity_to_the_Northeast_Greenland_Ice_Stream
Seems to be a MEASURED increase in geothermal flux between 2005 and 2010 at this location.
Let’s not forget that the Greenland magma plume is still connected to the Icelandic magma sack….which we know is still highly active.
Quote from link above….
Of course…. geothermal springs must be because of the increased atmospheric CO2.. that’s right, isn’t it ???
This map give an indication of the geothermal hot ponds and their temperatures.
Gees that CO2 is powerful stuff !! 😉
Sheesh. As usual You-reek Alert gets it all wrong. Apparently they haven’t even heard of seismic tomography. And they don’t even provide a link to the actual paper. Here is one:
https://www.essoar.org/pdfjs/10.1002/essoar.10502596.1
And, no, there is no plume or hotspot under Greenland. It is under Iceland. But the plume did pass under Greenland from 80 to 20 million years ago, and there is still residual heat along the old track, which explains the high heat flow under parts of Greenland. This has been understood for some time, but these data are much more detailed. The connection between the geothermic zone in Svalbard and the Jan Mayen plume is new though.