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OffTheGrid

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Newly Discovered Greenland Plume
« on: April 22, 2021, 06:26:51 PM »
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.

https://www.tohoku.ac.jp/en/press/greenland_plume_drive_thermal_activities.html
« Last Edit: April 24, 2021, 10:00:44 AM by oren »

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #1 on: April 22, 2021, 06:41:34 PM »

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JB019837

Abstract

We study the 3‐D P wave velocity (Vp) structure of the crust and upper mantle beneath Greenland and surrounding regions using the latest P wave arrival time data. The Greenland Ice Sheet Monitoring Network (GLISN), initiated in 2009, is an international project for seismic observation in these regions using 34 stations. We use a regional seismic tomography method to simultaneously invert P wave arrival times of local earthquakes and P wave relative traveltime residuals of teleseismic events. These data are extracted from the ISC‐EHB catalog; however, for the teleseismic data, we picked new arrival times from seismograms using a cross‐correlation method. Our tomographic results clearly reveal the Iceland plume, the Jan Mayen plume, and a newly discovered “Svalbard plume,” which merge together in the mantle transition zone. A high‐Vp body exists beneath the Greenland Sea, which might act as an obstacle against the rising Svalbard plume. Furthermore, our results reveal a remarkable low‐Vp anomaly elongated in the NW‐SE direction at depths ≤250 km beneath central Greenland, which is connected with the Iceland and Jan Mayen hotspots. Although previous studies have suggested a similar feature, our result is the first to show the low‐Vp zone existing at all depths in the Greenland lithosphere, and its spatial distribution coincides with a high heat flux region. These characteristics indicate that the low‐Vp zone reflects residual heat from the Iceland plume when the Greenland lithosphere passed over this plume at ~80–20 Ma. Our results also indicate the possible existence of residual heat from the Jan Mayen plume.


Plain language summary

Greenland is a stable land mass that has preserved ~4 Gyr of Earth's history. In its vicinity, there are the Mid‐Atlantic Ridge, the Iceland and Jan Mayen hotspots, and a geothermal area in Svalbard, which indicate the complexity of this region. We apply seismic tomography to analyze the latest data recorded by a new seismograph network, and we obtain detailed 3‐D images of the crust and upper mantle. Our results clearly image the conduit‐like Iceland plume, the Jan Mayen plume, and a newly discovered “Svalbard plume,” which merge together in the mantle transition zone. These new findings will improve our understanding of the tectonic and thermal evolution of this region. We also find a low seismic velocity zone running in the NW‐SE direction beneath central Greenland, which is connected with the Iceland and Jan Mayen hotspots. This zone is located within the Greenlandic plate, and its spatial distribution agrees well with an area of high geothermal heat flux. These results suggest that the low‐velocity zone reflects residual heat from the Iceland plume when the Greenlandic plate passed over the plume at ~80–20 Ma. Our model further suggests a possible heat track left by the Jan Mayen plume.

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #2 on: April 22, 2021, 08:18:36 PM »
A few quick comments to provoke discussion:

-You may notice in the first image, an extra western branch feeding the ex-Hudson bay area, and an eastern root connecting to the currently deglaciated base of the Great Britain-Scandanavian continental massive. Given that Greenland in interstadials such as now, has far more ice overburden on its very large and very fluid (low VP or pressure wave velocity ) underlying magmatic body than in stadial intervals, we might hypothesise with some confidence that a hydraulic see-saw pumps very hot and low viscosity basalt volume at depth to reinvigorate the subcontinental reservoirs after each stadial/interstadial flip-flop.

- The low Vp of the central Greenland reservoir is symptomatic of the combined effects of hyper-corrosive supercritical geofluids and the high temperatures, circa 1400-2000C basalt incorporating remelt of surrounding rocks of far lower melting point into the magma chambers of the supervolcano caldera field that underlies the entire central Greenland Ice Dome. This produces a highly enriched in silicates, carbonates, hydrated minerals, and dissolved gases magma body technically described in the field of vulcanology as a "crystal slush". Depressurising such a magmatic body causes the recombination of light elements that are primarily free radical and ionic species in these conditions, creating the explosive supervolcano events that so violently punctuate stadial/interstadial transitions. I recommend a paper "bipolar SO2 signatures correlation with stadial/interstadial transitions" which investigates the signatures found in both Greenland and Antarctic ice cores and the tight +/- around fifty to 100 year bounding of over 50 such transitions in the last 100 thousand years of you want to delve into this. I have it somewhere in my archives, but with my tendancy to digest some dozen of the relevant papers per day in whatever specialist area I am in a research frenzy of assimilating, and the pdf filenames being usually indecipherable. They can be difficult to locate in the thousands of papers per year I tend to accumulate.

-The high Vp zone "blocking the Svalbard branch" is most likely symptomatic of geofluid flux from the NE ice streamcreating high pressure  below the creating crystal mineral hydrate deposits, or quenched trench erupted basalt dyking from the mid Atlantic spreading zone that passes through Iceland and  has a canyon head just SW of Svalbard, where SST peaked at 22+C a couple of years ago. Before Nullschool had their arms twisted to change their data sourcing to a feed that chucked out such inconvenient and Impossible data outliers in its AUi programming. 🙄 An all too common practice in geology unfortunately. This spreading zone then plunges to become the Gakkel and crosses near the pole to the laptev.

-Lastly but not leastly. Treat any dating such as the "Iceland plume passed under Greenland circa ~80-25 milion years ago" with extreme skepticism. Volcanos regularly produce fresh igneous rock that potassium argon dates at 90 million years or older. Remelt and fresh gas inclusion from the depths are factors. And the reference to Greenland passing over the Iceland hotspot is just politeness to crusty old tenured professors. Theory of fixed deep  mantle plumes and plates drifting over them is on very shaky ground these days.  Though you won't see that admitted in "basic books on geology" as provided to students, incase the grocery store runs out of loo paper.🤭

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #3 on: April 24, 2021, 05:22:45 AM »
Deepest apology to our esteemed Japan colleges for personal undisciplined sloppiness in not reading companion paper before above comments.
Great thanks for most enlightening studies of complex systems that lie below all our feet.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020JB019839

P Wave Tomography Beneath Greenland and Surrounding Regions: 2. Lower Mantle
Genti Toyokuni
Takaya Matsuno
Dapeng Zhao
First published: 30 October 2020
https://doi.org/10.1029/2020JB019839
Citations: 3
This article is a companion to Toyokuni et al. (2020), https://doi.org/10.1029/2020JB019837.


Abstract

We study the 3‐D P wave velocity (Vp) structure of the whole mantle beneath Greenland and surrounding regions using the latest P wave arrival time data. We use a new method of global seismic tomography by setting 3‐D grid nodes densely in the study volume to enhance the resolution. We invert ~5.6 million arrival times of P, pP, and PP waves from 16,257 earthquakes extracted from the ISC‐EHB catalog, which were recorded at 12,549 seismic stations in the world. Our results reveal a hot plume rising from the core‐mantle boundary beneath central Greenland, which is called the Greenland plume. This plume has the main conduit and two branches in the lower mantle, and the main conduit rises to the mantle transition zone (MTZ) beneath eastern Greenland, so it is distinguishable from the Iceland plume that appears to rise from a midmantle depth (~1,500 km) beneath Iceland. The Iceland plume itself is a powerful plume, but it may also be fed by hot mantle materials from three joints with other plumes: a branch of the Greenland plume at ~1,500 km depth, a plume beneath Western Europe at ~1,000 km depth, and the main conduit of the Greenland plume at the MTZ, leading to many active volcanoes in Iceland. We deem that the main conduit of the Greenland plume mixes with the Iceland plume incompletely and splits mainly into the Jan Mayen and Svalbard plumes in the upper mantle, which supply magma to the Jan Mayen hotspot and a geothermal area in western Svalbard, respectively.

Plain Language Summary

Greenland and its surrounding regions have many clues for understanding global‐scale tectonics of the Earth. Seismic tomography is a well‐established method for obtaining 3‐D images of the underground structure by inverting a large number of seismic wave arrival times. We obtain detailed tomographic images of the whole mantle beneath Greenland and adjacent regions using the latest dataset. Our high‐resolution results show that the so‐called Iceland plume could be composed of two plumes. One is located directly beneath Iceland but rising from ~1,500 km depth, which we call the Iceland plume. The other is rising from the core‐mantle boundary beneath central Greenland, which we call the Greenland plume. The Greenland plume has the main conduit and two branches in the lower mantle, and the main conduit rises to the mantle transition zone beneath eastern Greenland. Although the Iceland plume itself is a powerful plume, it may also have three joints with other plumes: the main conduit and a branch of the Greenland plume, and a plume beneath Western Europe, resulting in many active volcanoes in Iceland. The main conduit of the Greenland plume may also supply magmas to the Jan Mayen hotspot and a geothermal area in western Svalbard.

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #4 on: April 24, 2021, 07:26:44 AM »
P Wave Tomography Beneath Greenland and Surrounding Regions: 2. Lower Mantle
Genti Toyokuni

Enjoy. 👍

grixm

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Re: Newly Discovered Greenland Plume
« Reply #5 on: April 24, 2021, 08:43:23 AM »
If the heat melts the ice from below, do they know how fast this happens? Is it a significant source of melt, or negligible?

oren

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Re: Newly Discovered Greenland Plume
« Reply #6 on: April 24, 2021, 09:59:49 AM »
And has this changed recently? Which I strongly doubt.

Shared Humanity

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Re: Newly Discovered Greenland Plume
« Reply #7 on: April 24, 2021, 02:28:04 PM »
I would think that as the Greenland ice sheet melts and the crust rebounds, we will see an increase in volcanic activity beneath the ice sheet. The impact will be very slow and easily discounted by the non scientist.

johnm33

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Re: Newly Discovered Greenland Plume
« Reply #8 on: April 24, 2021, 04:14:59 PM »
Last summer there were some oddities that were possibly associated with Gakel ridge. For instance https://classic.nullschool.net/#2020/09/16/2300Z/ocean/primary/waves/overlay=sea_surface_temp/orthographic=-3.48,88.34,633/loc=42.062,85.175

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #9 on: April 24, 2021, 11:02:44 PM »
Yes most certainly the heat melts the ice from below. Published estimates vary from 120W to 900W per square meter under the head of the NE ice stream.  Comparing that with the averaged annual surface energy inputs, you can't avoid the conclusion that it is by far the largest mechanism for ice mass loss. In fact basal outflow minimum in winter has risen to well over peak summer outflows ten years ago.

<Warning, read this with caution as the above numbers are ludicrous and have not been backed up as requested. O>

Unfortunate that the scientific culture doesn't encourage mention of unknown unknowns in published papers, so you won't find anything but a passing mention. Compounding the difficulty of distinguishing between what's dropped down to the basement through moulin and crevasses, is the reality that what is released as jokkulup outbursts from glacial fronts is sporadic, the pressure melting point of the ice is as low as -7C, the decompression cooling from 2km of hydrostatic pressure is ~5C, and the highly variable dissolved minerals, organics, and entrained particulates content make many of these basal outbursts travel on the bottom for many km, even hundreds or thousands. The sudden jump in turbidity and anoxification of the entire Atlantic side of the Lomonosov ridge , at least to 700m that the last couple of years of itp traverses have revealed is an effect I have previously suggested this to be a major contributor to.
We have identified outbursts emitting directly from the canyoned till complex on the edge of the shelf off the 79Nth glaciers, directly across the strait from Svalbard last fall. No-one has a clue how to quantify the volumes of these oceanic bed emissions, however a study published last year admitted that freshwater input to the entire Arctic Basin  has been previously underestimated, with the undersea outputs doubling previously trusted figures. As that was mostly based on the flows from Eurasia and Alaska. It is probably underestimated too.

The resolution of recent magnetic anomaly and seismic studies of the top 100 km of the Greenland basement is appalling, with 120 km hexagonal mesh grids. But has revealed that the central East and NW both have rock above the 550C curie temperature of magnetite "at or above the Moho solid liquid transition zone", at depths of 30km or less.  Quite simply this means large areas of hydrated mineral crystal slush porridge of the most explosive magmatic types.
Bore hole studies of the ice dome quote basement hydrostatic pressures at or within ten percent of the ice overburden mass.
This simple equilibrium reaction might help with understanding of why this scenario is so dangerous.
Supercritical water equation:
2Hydrogen+ 1Oxygen  (at high temp and pressure) <> H2Og + energy
Here, a reduction in pressure or temperature drives the equation to the right, with the MONOTOMIC hydrogen and oxygen radicals recombining to Water gas.
The energy realeased is tenfold compared to the more familiar 2H2 + O2 > 2H2Ogas.
Because you don't need expend energy to break the covalent bonds of the H2 and O2 before recombining them into the slightly lower energy H2O molecule.

Of course it's not just water but all the light elements that are acting as a powerful thermal energy storage battery in these Magmatic bodies, with little or no covalent bonds remaining.

Some might recall the Uniformatarianist plaintive plea that ice sheets cannot melt quickly and abruptly because no mechanism exists to supply the large quantities of energy for the phase change. Well...there you have it. Growing ice sheets store chemical energy in supercritical geofluid drenched magma beneath. Become unstable, Release that energy.
Appalling to see mention in Toyokuni that there was only one seismic station in Greenland until after 2009.
There have been some very large SO2 pulses from the Central Dome, visibly cascading through the basal swamp lake river systems and surfacing at or offshore from the major glacial fronts in the last six months.
Enough for now, busy day to initiate.
All the best.
« Last Edit: April 27, 2021, 03:25:54 AM by oren »

FishOutofWater

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Re: Newly Discovered Greenland Plume
« Reply #10 on: April 25, 2021, 06:23:05 AM »
Don't conclude that the Greenland plume surfaces under Greenland. It once did, and there was a huge outpouring of lava in southern Greenland, but most of that activity is now surfacing at Iceland and the other sites mentioned in the abstract. Decompression melting with the decline of Iceland's glaciers is a real and major concern. Perhaps someone has a report that shows concern about renewed volcanic activity on Greenland but this article isn't it.

Shared Humanity

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Re: Newly Discovered Greenland Plume
« Reply #11 on: April 25, 2021, 01:58:38 PM »
Yes most certainly the heat melts the ice from below. Published estimates vary from 120W to 900W per square meter under the head of the NE ice stream.  Comparing that with the averaged annual surface energy inputs, you can't avoid the conclusion that it is by far the largest mechanism for ice mass loss. In fact basal outflow minimum in winter has risen to well over peak summer outflows ten years ago.
Unfortunate that the scientific culture doesn't encourage mention of unknown unknowns in published papers, so you won't find anything but a passing mention. Compounding the difficulty of distinguishing between what's dropped down to the basement through moulin and crevasses, is the reality that what is released as jokkulup outbursts from glacial fronts is sporadic, the pressure melting point of the ice is as low as -7C, the decompression cooling from 2km of hydrostatic pressure is ~5C, and the highly variable dissolved minerals, organics, and entrained particulates content make many of these basal outbursts travel on the bottom for many km, even hundreds or thousands. The sudden jump in turbidity and anoxification of the entire Atlantic side of the Lomonosov ridge , at least to 700m that the last couple of years of itp traverses have revealed is an effect I have previously suggested this to be a major contributor to.
We have identified outbursts emitting directly from the canyoned till complex on the edge of the shelf off the 79Nth glaciers, directly across the strait from Svalbard last fall. No-one has a clue how to quantify the volumes of these oceanic bed emissions, however a study published last year admitted that freshwater input to the entire Arctic Basin  has been previously underestimated, with the undersea outputs doubling previously trusted figures. As that was mostly based on the flows from Eurasia and Alaska. It is probably underestimated too.

The resolution of recent magnetic anomaly and seismic studies of the top 100 km of the Greenland basement is appalling, with 120 km hexagonal mesh grids. But has revealed that the central East and NW both have rock above the 550C curie temperature of magnetite "at or above the Moho solid liquid transition zone", at depths of 30km or less.  Quite simply this means large areas of hydrated mineral crystal slush porridge of the most explosive magmatic types.
Bore hole studies of the ice dome quote basement hydrostatic pressures at or within ten percent of the ice overburden mass.
This simple equilibrium reaction might help with understanding of why this scenario is so dangerous.
Supercritical water equation:
2Hydrogen+ 1Oxygen  (at high temp and pressure) <> H2Og + energy
Here, a reduction in pressure or temperature drives the equation to the right, with the MONOTOMIC hydrogen and oxygen radicals recombining to Water gas.
The energy realeased is tenfold compared to the more familiar 2H2 + O2 > 2H2Ogas.
Because you don't need expend energy to break the covalent bonds of the H2 and O2 before recombining them into the slightly lower energy H2O molecule.

Of course it's not just water but all the light elements that are acting as a powerful thermal energy storage battery in these Magmatic bodies, with little or no covalent bonds remaining.

Some might recall the Uniformatarianist plaintive plea that ice sheets cannot melt quickly and abruptly because no mechanism exists to supply the large quantities of energy for the phase change. Well...there you have it. Growing ice sheets store chemical energy in supercritical geofluid drenched magma beneath. Become unstable, Release that energy.
Appalling to see mention in Toyokuni that there was only one seismic station in Greenland until after 2009.
There have been some very large SO2 pulses from the Central Dome, visibly cascading through the basal swamp lake river systems and surfacing at or offshore from the major glacial fronts in the last six months.
Enough for now, busy day to initiate.
All the best.

All of this post is interesting. Would really prefer you link to research that I can read.

oren

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Re: Newly Discovered Greenland Plume
« Reply #12 on: April 25, 2021, 02:07:45 PM »
Quote
Yes most certainly the heat melts the ice from below. Published estimates vary from 120W to 900W per square meter under the head of the NE ice stream.  Comparing that with the averaged annual surface energy inputs, you can't avoid the conclusion that it is by far the largest mechanism for ice mass loss.
900W/m2 sounds like a gross exaggeration. You need to post supporting evidence or I will delete a large part of your esaay.

Tor Bejnar

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Re: Newly Discovered Greenland Plume
« Reply #13 on: April 25, 2021, 08:03:51 PM »
If Greenland Ice Shield melting, due to a plume near the surface under any part of interior Greenland, was at all significant, the Greenland mass change maps would show the loss.  I don't see it.

This is not to say there isn't a plume under Greenland currently venting offshore (Iceland, etc.).  I've not read much about the glaciation-volcanism seesaw concept; if relevant, 'watch out!' in 1000 or 2000 years!
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

kassy

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Re: Newly Discovered Greenland Plume
« Reply #14 on: April 25, 2021, 08:06:26 PM »
I bet there is also some water between the localized plume and the ice which delutes that measurement unlike averaged annual surface energy inputs.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Richard Rathbone

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Re: Newly Discovered Greenland Plume
« Reply #15 on: April 26, 2021, 06:59:57 AM »
Quote
Yes most certainly the heat melts the ice from below. Published estimates vary from 120W to 900W per square meter under the head of the NE ice stream.  Comparing that with the averaged annual surface energy inputs, you can't avoid the conclusion that it is by far the largest mechanism for ice mass loss.
900W/m2 sounds like a gross exaggeration. You need to post supporting evidence or I will delete a large part of your esaay.

Rock thermal conductivity 5 W/m/K
Thermal flux 500 W/m2
Temperature gradient 100 K/m

Thats the sort of temperature gradient in the immediate vicinity of an eruption. The molten rock would just be a few metres from the ice. A "milli" went missing?

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #16 on: April 27, 2021, 05:55:56 AM »
I bet there is also some water between the localized plume and the ice which delutes that measurement unlike averaged annual surface energy inputs.

Yes, exactly.
There is a huge volume of published literature arguing about the heat flux causing the wet bottom and speed of the NE ice stream.
The consensus at this time tends to be that it is similar to the flux at the Yellowstone Caldera.
The Bedmap data has been quoted as showing recent volcanic features in in some of the literature. That would not have survived more than a few thousand years. Unfortunately apart from a few specific area, although interpolated at 50m resolution, they have only an actual data resolution of 500m to 1.5km.
Most of the heat is being pumped away by water through subbasement strata at present. The radar cannot penetrate liquid water.
There was another central blowup a few days ago visible on the Nullschool, chem, surface SO2  maps,  starting under the NE ice stream head. And emerging at and off the coasts, both east and west, within 24 to 48 hrs. I have 16 frames to animate of that one. But internet here is sporadic. Perhaps I will get some clear reception tonight.
Mid event image attached.
These have been regularly occurring since September, mostly at full and new moons when tidal forces are highest, and strongly correlate with Antipodal Ross Archipelago thru transantarctic mountains events. The P waves refocus on the other side of the planet, and the compression-decompression triggers the chemical energy release I explained above.
You can also see PGAS and north Baffin Island SO2 hotspots in this image though the Baffin one may be anthropogenic, the PGAS one is certainly not.
If you want the best understanding in the world of these processes rope in Veli. He can explain all the high pressure chemistry and nuclear processes that are involved near the core mantle boundary at the base of these hotspot systems better than anyone else in the world. For example the high He3 anomaly at Jan Mayen compared to Iceland.
As for Grace, Bedmap is just a snapshot. With fast cyclic changing pressures and magmatic and hydrothermal responses at the base of the ice sheet. We don't know how much basal compressions and uplifts, and changing densities in the magma chambers...   are affecting attempts to quantify the ice sheet volume. And Grace is appallingly low resolution.


I think someone forgot the prefix "milli" on that problem in 1000 to 2000 years comment.

The tide buoy network in NZ for example is now showing a polynomial best fit of three meters of sea level fall by 2050 from the last five years data. They are lucky on that side of the planet. Antarctica is mostly bedded below sealevel on that side of the planet. And perhaps some remember about a decade ago the modelling of earth's centre of mass shifting the axis it spins on by about 150 m towards the Atlantic if just  West Antarctica collapsed?
In the last five years we have learned that East Antarctica on that side is mostly bedded below sealevel too. And thus vunerable too to rapid collapse.


Sorry Oren. This stuff was all resolved globally in and presented in pretty three D images by NASA 15 years ago. The deep fluid basalt conduits connecting continental keels to the Mid oceanic spreading zones, combined with surprise data showing identical chemical makeup of sections of those MOSZ up to 600 km long, and current heat fluxes at the MOSZ'S Similar to subduction zones at the continental shelves. Well..
That killed steady state mantle convection driven plate tectonics models right there and then.
Not up for attempting reproving such done and dusted ancient history geology with the much compromised search engines and paywalled and buried literature access of this "Brave New World".
Good luck.

oren

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Re: Newly Discovered Greenland Plume
« Reply #17 on: April 27, 2021, 06:08:44 AM »
All words and no supporting evidence make Jack a dull boy, is all I can say.

sidd

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Re: Newly Discovered Greenland Plume
« Reply #18 on: April 27, 2021, 09:15:42 AM »
Re: a polynomial best fit of three meters of sea level fall by 2050 from the last five years data

Neat, a 28 year forecast from five years of data, a fine exhibit of numerology.

sidd

nukefix

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Re: Newly Discovered Greenland Plume
« Reply #19 on: April 27, 2021, 02:31:04 PM »
Full crackpot territory.  >:(

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #20 on: April 28, 2021, 01:48:27 AM »
Nope.
A sudden reversal of the trend. The straight line trend is similar.
And no nothing know it alls are the reason most of they with brains and knowledge to contribute have walked from the ASIF in the last few years.

We've seen some improvements since Oren took over moderation. Nevens heavy-handed deletion of anything that didn't fit with his own theory's, and editing others posts to support his claims they said things they did not, another.
I have some empathy for him. Both of us had Yugoslavian fathers who died within a month of each other. Helps me understand his national psyche.
Best way to learn is to keep your eyes open, do your own research, realise that you KNOW nothing, and that published peer reviewed science, and what is taught institutionally is held back by the protection of reputations by those who have been confidently asserting that things are facts proven.
The thermal flux being equal in the currently dormant mid ocean trench and subduction trench and homogeneous chemical composition of the midocean trench basalt over 600 km findings were the south Pacific/south America system.
The seismic study published by NASA showing that seafloor basalt blocks ooze down the bottom of the continents
Become very hot and fluid, due to continents insulating the heat produced by nuclear processes near or in the core, and return to the mid ocean trench via km scale conduits, also showing the low viscosity puddles of hydrate and carbonate rich magma the continents float in... That one myself and AMEG chairman John Nissan spent days of Google searching to try an retrieve in 2013. Unsuccessfully.
Some may know of the stacked Ocean Floor sedimentary sections that the North American Western seaboard is composed of. Drilling down you go through older and older layers then suddenly you find a younger than surface layer, that overlays a progression of older ones. Spaced about 500m to a km, at least five, the youngest at the bottom. Same in South America. You used to be able to see the ~50 to 100 km wide, parallel fractured seafloor blocks extruded from the midocean trenches in active pulses on Google maps. Until about 5 years ago.
I have many friends in the military, special forces engineers etc. The US Navy has maps showing what they expect their continent to look like within the next few decades. An inland sea connecting the gulf of Mexico to the great lakes and Hudson bay etc. Their top brass have all been retiring to high mountain areas far inland from the coast for twenty years.
I have very little capacity for faith in anything. To believe for me extends from I believe there is a small chance this may be true to this is almost certainly true.
My engineering mindset is forward looking, to prepare for the worst that might happen. Unlike the scientific mindset which is restricted to study and analyse the past.
Both have worth.
The younger Dryas event plunged average July temperatures in Europe by 20C in 1 year. 
Perhaps the little ice age/ black death event was due to the collapse of the North Himalayan Plateau ice dome and created the outwash plain we see in this image that came from the Lake Baikal vent.
Perhaps this is what Greenland will look something like after the imminent Final Dryas of this interstadial. And Almost Certainly looked like after the final Dryas of the Eemian.


<It's not Neven or Oren, it's nonsensical posts getting deleted. Sorry. O>
« Last Edit: April 28, 2021, 02:19:16 AM by oren »

wehappyfew

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Re: Newly Discovered Greenland Plume
« Reply #21 on: April 28, 2021, 02:19:08 AM »
Quote
I have many friends in the military, special forces engineers etc. The US Navy has maps showing what they expect their continent to look like within the next few decades. An inland sea connecting the gulf of Mexico to the great lakes and Hudson bay etc. Their top brass have all been retiring to high mountain areas far inland from the coast for twenty years.

Surely this is enough to pull the plug on this fiasco.

This is not the place to parade one hare-brained conspiracy theory after another.
"If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. It’s simply too painful to acknowledge, even to ourselves, that we’ve been taken" - Carl Sagan

oren

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Re: Newly Discovered Greenland Plume
« Reply #22 on: April 28, 2021, 02:20:06 AM »
Indeed...

Shared Humanity

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Re: Newly Discovered Greenland Plume
« Reply #23 on: April 29, 2021, 12:15:46 AM »
All words and no supporting evidence make Jack a dull boy, is all I can say.

 :)

Shared Humanity

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Re: Newly Discovered Greenland Plume
« Reply #24 on: April 29, 2021, 12:20:44 AM »
Quote
I have many friends in the military, special forces engineers etc. The US Navy has maps showing what they expect their continent to look like within the next few decades. An inland sea connecting the gulf of Mexico to the great lakes and Hudson bay etc. Their top brass have all been retiring to high mountain areas far inland from the coast for twenty years.

Surely this is enough to pull the plug on this fiasco.

This is not the place to parade one hare-brained conspiracy theory after another.

Where did that quote come from? Was that posted here?

Christ on a cracker!

wehappyfew

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Re: Newly Discovered Greenland Plume
« Reply #25 on: April 29, 2021, 02:49:49 AM »
I quoted part of reply #20 from OffTheGrid.

It's still there, but ... diminished. Oren muted it by converting it to font size = 1pt.  ;D

OTG hasn't posted since, so either felt enough opprobrium to refrain from posting, or has been banned. Either way, a big improvement.

"If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. It’s simply too painful to acknowledge, even to ourselves, that we’ve been taken" - Carl Sagan

RoxTheGeologist

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Re: Newly Discovered Greenland Plume
« Reply #26 on: April 29, 2021, 09:39:30 PM »
Nope.
A sudden reversal of the trend. The straight line trend is similar.
And no nothing know it alls are the reason most of they with brains and knowledge to contribute have walked from the ASIF in the last few years.

We've seen some improvements since Oren took over moderation. Nevens heavy-handed deletion of anything that didn't fit with his own theory's, and editing others posts to support his claims they said things they did not, another.
I have some empathy for him. Both of us had Yugoslavian fathers who died within a month of each other. Helps me understand his national psyche.
Best way to learn is to keep your eyes open, do your own research, realise that you KNOW nothing, and that published peer reviewed science, and what is taught institutionally is held back by the protection of reputations by those who have been confidently asserting that things are facts proven.
The thermal flux being equal in the currently dormant mid ocean trench and subduction trench and homogeneous chemical composition of the midocean trench basalt over 600 km findings were the south Pacific/south America system.
The seismic study published by NASA showing that seafloor basalt blocks ooze down the bottom of the continents
Become very hot and fluid, due to continents insulating the heat produced by nuclear processes near or in the core, and return to the mid ocean trench via km scale conduits, also showing the low viscosity puddles of hydrate and carbonate rich magma the continents float in... That one myself and AMEG chairman John Nissan spent days of Google searching to try an retrieve in 2013. Unsuccessfully.
Some may know of the stacked Ocean Floor sedimentary sections that the North American Western seaboard is composed of. Drilling down you go through older and older layers then suddenly you find a younger than surface layer, that overlays a progression of older ones. Spaced about 500m to a km, at least five, the youngest at the bottom. Same in South America. You used to be able to see the ~50 to 100 km wide, parallel fractured seafloor blocks extruded from the midocean trenches in active pulses on Google maps. Until about 5 years ago.
I have many friends in the military, special forces engineers etc. The US Navy has maps showing what they expect their continent to look like within the next few decades. An inland sea connecting the gulf of Mexico to the great lakes and Hudson bay etc. Their top brass have all been retiring to high mountain areas far inland from the coast for twenty years.
I have very little capacity for faith in anything. To believe for me extends from I believe there is a small chance this may be true to this is almost certainly true.
My engineering mindset is forward looking, to prepare for the worst that might happen. Unlike the scientific mindset which is restricted to study and analyse the past.
Both have worth.
The younger Dryas event plunged average July temperatures in Europe by 20C in 1 year. 
Perhaps the little ice age/ black death event was due to the collapse of the North Himalayan Plateau ice dome and created the outwash plain we see in this image that came from the Lake Baikal vent.
Perhaps this is what Greenland will look something like after the imminent Final Dryas of this interstadial. And Almost Certainly looked like after the final Dryas of the Eemian.


<It's not Neven or Oren, it's nonsensical posts getting deleted. Sorry. O>

Hmm - training in Geophysics suggests that the whole post is dubious. The Greenland plate moved over the hotspot and has left a trail of low velocity asthenospheric elevated temperatures. Hotspot plumes originate deep in the mantle and are seemingly decoupled from plate motion as is beautifully illustrated by the Emperor- Hawaii seamount chain.

When there is a hot spot, you see obvious volcanism in the ocean (Iceland, Hawaii, Tristan) and on land by volcanism and elevated topography (Tibesti, Afar, Yellowstone). Old ocean hotspots (no longer active) are characterised by submersed seamounts, on land by flood basalts (Deccan Traps, Eastern Greenland, Colombia River Basalts, Tasmania Basalts).  The fact that there isn't active volcanism below east Greenland shows that the plate is no longer over the plume.




gerontocrat

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Re: Newly Discovered Greenland Plume
« Reply #27 on: April 29, 2021, 10:01:55 PM »
What is interesting is that otg decided to try his version of Armageddon on this forum.

There is a vast array of sites which welcome with open arms this sort of stuff - especially the conspiracy bit about the US military knowing all and telling us nothing.

I'm almost sorry that the moderators had no choice but to stop it. They could have moved it to the Arctic Humour thread?
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oren

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Re: Newly Discovered Greenland Plume
« Reply #28 on: April 29, 2021, 10:44:37 PM »
OTG is not in moderation, but any new irrelevant ramblings and conspiracies will now be deleted on sight.

VeliAlbertKallio

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Re: Newly Discovered Greenland Plume
« Reply #29 on: May 09, 2021, 10:37:46 AM »
A rather important new paper has been published 9th April 2021 on heat fluctuations in Greenland ice cores which is worthwhile reading: https://www.nbi.ku.dk/english/news/news21/abrupt-ice-age-climate-changes-behaved-like-cascading-dominoes?fbclid=IwAR0QzFJRbTXc_uF8fn3v7yEFhLm717161fn8dSbDqLXmwrtidNA-eti2Ihk

Authors do not mention ice ages' large volcanism events like effusive lava floods i.e. the East Greenland Sea associated with Iceland as a possible cause. However, nucleation of gases occur due to reduced pressure (ice sheet mass balance change). Many very large eruptions coincided the Ice Ages period. The subglacial geology of the rocks are also very little known in Greenland.
https://www.sciencealert.com/ancient-climate-events-reveal-no-clear-trigger-only-hallmarks-of-sudden-catastrophe?fbclid=IwAR27XVE75YUMnoHEIb9U8e6GEEXN70zJPtIdGubUR1btpQmuzdjTo5GTL_0

As per geothermal activity, I am aware of only one active terrestrial hot water spring currently in action in Greenland. In addition there are several more hot springs on Greenland's sea slopes.

I wouldn't completely exclude branching of lava conduits, lava pockets, or potentially new faults forming in bedrocks if ice losses became massive due to slip-slide events or collapses of frozen coastal bedrocks in a very large scale land slip event. However, ALL observed volcanism is currently on Iceland - Jan Mayen ridge. Water penetration from above to salt minerals dissolves them, while olivine group minerals like Peridotite destabilises by water in partial-melting process.

Abrupt events that are unpredictable are a matter of fact, but that does not justify any claims at present that there "are" active volcanic plumes in operation in Greenland at the moment. The hot springs in Greenland are best explicable by generically hot rocks in deep subterranean plumbing network of (undoubtedly) incredibly shattered Greenland hot (but solid) bedrocks.

However, large swings in climate conditions are seen in Greenland's ice cores. Currently, these are assigned to other causes synchronously amplifying each other to produce the observed vast climate swings as seen in Greenland ice cores.

The Independence Fjord which sits in downstream from Iceland and Jan Mayen did have open seaside all year round and supported the Independence I Culture in North East Greenland corner. Despite extreme proximity to the North Pole, the people lived in only tiny leather tents in the area which is out of question today. The elevated sandy beaches in this area indicate lack of sea ice and freezing. If heated volcanic tail current from Iceland, it then would also explain some of the wild climate fluctuations seen in Greenland ice cores that are close to Icelandic / East Greenland Sea. 
https://www.nature.com/articles/s41467-021-22241-w?fbclid=IwAR1B5J2hyjN8olRfhUF7vrkGLtn1qWi0aqw0BJwmSE3HVkM7Tynvo6mP7FI

UNESCO and the Bolivian government invited to present based on ancient ethnic recollections that suggest link between violent collapse of ice sheet: the great earthquake of the east (cabracan) and the volcanism storm of the west (zipcana). I speculated that if the ice sheet mass balance changes dramatically from ablation, slip-sliding ice or very large scale glacier debris flows (GDFs) as ice approaches its melting temperature and so weakens to soft or rotten ice (with its underside also increasingly wet and potholes filled with water) that below ice-volcano coupling drama may occur:


Heindrich Ice Berg Calving events followed by Cold Dryases could result from sudden massive loss of ice weight from the ice sheets resulting in instant cooling of ocean and climate as has been observed. Such events could generate enough stresses for new faults and incursion of plutonic rocks from any hot intrusion pocket to become destabilised with its containment integrity compromised and extrusion resulting via new or dormant channel. In extreme case (if it existed and happened) it can lead into a tight feedback loop where overlying ice is melted away by magma incursion at rate where the resulting nucleation of gases in magmatic rocks run at rate high enough to self-sustain the eruption which only fizzles out when all ice gone.

Someone has suggested Pine Island glacier melting pulses in Antarctic being partly caused by the subglacial eruptions eating ice away while the Gamburtsev Range having been created to the middle of Antarctica by the weight of ice sheet's periphery pushing continental edges down to generate deep fault in litosphere leading to eruption as the centre began to bulge upwards as a back action. Collapse of the Ice Sheet or large part of it could also be behind this observed instant cooling of ocean and climate:
« Last Edit: May 09, 2021, 11:07:04 AM by VeliAlbertKallio »
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nukefix

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Re: Newly Discovered Greenland Plume
« Reply #30 on: May 10, 2021, 03:34:36 PM »
I speculated that if the ice sheet mass balance changes dramatically from ablation, slip-sliding ice or very large scale glacier debris flows (GDFs) as ice approaches its melting temperature and so weakens to soft or rotten ice (with its underside also increasingly wet and potholes filled with water)
That indeed sounds like speculation - are you proposing a new ice sheet failure process that is not known to the glaciological community?

OffTheGrid

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Re: Newly Discovered Greenland Plume
« Reply #31 on: May 11, 2021, 12:04:08 AM »
I have been monitoring the surface SO2 levels over the Arctic Ocean.
There are persistent point sources that can only be volcanic or hydrothermal in origin. Reviewing past years, you have to go back to 2016 at this time of year to find them absent.
It is apparent that since 2017 there has been a markedly increased level of Arctic Ocean seafloor activity.
Association is strongest with the Greenland to pole Gakkel/Lomonosov complex, Laptev bite, East Greenland shelf and Fram, between Chuckchi Plateau and Wrangel, and there are persistent deep ocean sources on the Beaufort.
Seafloor Bathometry is not great on the Arctic, however these sources all appear to have marked vent structures, and volcanic geology.
Wikipedia has some interesting background on the midocean Gakkel spreading zone. Which may no longer be dormant:
The ridge is the slowest known spreading ridge on earth, with a rate of less than one centimeter per year. Until 1999, it was believed to be non-volcanic; that year, scientists operating from a nuclear submarine discovered active volcanoes along it. In 2001 two research icebreakers, the German Polarstern and the American Healy, with several groups of scientists, cruised to the Gakkel Ridge to explore it and collect petrological samples. Among other discoveries, this expedition found evidence of hydrothermal vents. In 2007, Woods Hole Oceanographic Institution conducted the "Arctic Gakkel Vents Expedition" (AGAVE), which made some unanticipated discoveries, including the unconsolidated fragmented pyroclastic volcanic deposits that cover the axial valley of the ridge (whose area is greater than 10 km2). These suggest volatile substances in concentrations ten times those in the magmas of normal mid-ocean ridges.[3] Using "free-swimming" robotic submersibles on the Gakkel ridge, the AGAVE expedition also discovered what they called "bizarre 'mats' of microbial communities containing a half dozen or more new species".[4]

The Gakkel ridge is remarkable in that is not offset by any transform faults. The ridge does have segments with variable orientation and varying degrees of volcanism: the Western Volcanic Zone From the Lena trough, 7° W, to 3° E longitude), the Sparsely Magmatic Zone (from 3° E to 29° E longitude), and the Eastern Magmatic Zone (from 29° E to 89°E).[5] The gaps of volcanic activity imply very cold crust and mantle, probably related to the very low spreading rate, but it is not yet known why some parts of the ridge are more magmatic than others.[6] Some earthquakes have been detected from the mantle, below the crust, which is very unusual for a mid-ocean ridge.[7]

oren

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Re: Newly Discovered Greenland Plume
« Reply #32 on: May 11, 2021, 05:12:49 AM »
The above post moved here for lack of a better location, and irrelevance to the melting season. More irrelevant stuff will simply be deleted so make sure to backup your posts if you care about them.

Shared Humanity

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Re: Newly Discovered Greenland Plume
« Reply #33 on: May 11, 2021, 01:33:38 PM »
I have been monitoring the surface SO2 levels over the Arctic Ocean.


It is not difficult to provide links. Your comment appears to draw directly from research. Many here like to dig in to this research.

Please provide links when you are drawing on research.