Grønlands indlandsis i fare for kollaps

21. februar 2010

På Klimatopmødets sidste dag kom grundlæggeren af Environmental Parliament, Pano Kroko, til Klimabundmødet på Vartov for at give en direkte skildring af tingenes tilstand i Bella Centeret. Det stod da klart, at vi ikke ville få den ambitiøse aftale, som alle havde håbet på, og som verden fortjener. Det var alt for let at være fortvivlet, men endda fortalte Kroko, at der var grund til optimisme – måske ikke lige nu, men på sigt. Han havde oplevet delegationsledere fra hele verden indlevet vidende drøfte, om målet måtte være 1½° eller 2°C? Og en målsætning som 350 ppm, som ingen kendte til for blot to år siden, havde nu mere end 100 lande bag sig – omend endnu ikke de 100 mest indflydelsesrige. Så den nødvendige viden er til stede og mangler så at sige blot at befrugte den politiske vilje.

Kroko vendte tilbage til Vartov dagen efter, hvor han under mere uformelle rammer fortalte om en sag, som Environmental Parliament har meget højt opå sit agenda: Den fremadskridende destabilisering af Grønlands indlandsis. I de seneste år har man kunnet iagttage en markant større afsmeltning af den grønlandske indlandsis. På billedet ovenfor til venstre ser man to kajakker på en smeltevandssø ovenpå indlandsisen, til højre styrter smeltevand i en dyb skakt. Dette vand vådrer bunden af ismassivet og løsner permafrostens greb i det underliggende urfjeld. Der er tale om vandmængder så store, at det flere steder langs den grønlandske kyst giver basis for at drive elturbiner.

I Pano Krokos tankevækkende paper nedenfor, som jeg har fået lov at bringe her på bloggen, bliver det klart, at vi står overfor et muligt ‘tipping point’, hvor Grønlands ismassiver ikke blot langsomt silende ender i verdenshavene, men at det kan ske fra dag til dag gennem store udladninger af destabiliserede ismassiver med voldsomme havstigninger til følge.

Stadig sker afsmeltningen kun fra ismassivets randområder, men arealet er stærkt voksende (se det forudgående blog-indlæg: Indlandsisen vådrer), og det kolossale grønlandske ismassiv rummer i sig vandmængder, som fuldt afsmeltet modsvarer en havstigning på omkring 7 m.

indlæg oprettet af Jens Hvass

GREENLAND

Climate forcing sudden ice sheet collapse tipping point mitigation Study.

An Environmental Parliament white paper by Pano Kroko, circa November 2009

The Greenland Ice Cap sudden slide into the Ocean is the issue and we have to use security measures to counter it’s devastating effects. Clearly a Black Swan event waiting to happen – It is a security risk of the greatest magnitude for the United States and for the rest of the world.

The Greenland Ice Cap’s imminent, sudden and cataclysmic collapse is a repeat of PAST EVENTS in the Hudson Bay Ice Cap. Not only it is similar to the Hudson Bay Ice cap sudden collapse that led to the stories of Noah’s Flood and cultural and religious myth throughout all of the earth’s cultures – it is also a verifiable geologically proven rapid scale event. A singularity and a Complex theory examination is needed immediately.

The speed and terrifying cataclysmic sea level rises after the Hudson Bay Ice Cap collapse, are well documented. The sudden slide of the whole Greenland ice cap into the sea will result in 7 to 17 meter sea level rises globally. It can and will happen literally overnight…. This collapse will lead to sea level rising OVERNIGHT and subsequent sea level rises will result in our repeating the cultural and religious histories existent, all across cultures and religions of this earth.

Sadly this is going to be a repeat of the Floods but we aren’t any more prepared than the contemporaries of Noe were.

CHANGE IN HEAT TRANSPORTATION WITHIN THE GREENLAND GLACIER: SEASONAL MOULINS TO ACCUMULATIVE MOULINS

The key problem in Greenland, is the recent switch-over from Seasonal Impact Moulins at the periphery of Greenland’s ice sheet to Accumulative Impact Moulins; that reside at the high altitude, atop Greenland’s sub-glacial interior depression.

Until recently, virtually all moulins and crevasses formed along the margins of Greenland Ice Sheet where sub-glacial ground inclination is always seaward. Melt-water that falls through moulins or crevasses into ice takes with it the heat in it. At the edge of ice, this melt water (and heat in it) is quickly drained away from beneath ice sheet as the melt-water creeks soon poured out, taking the water and heat back to the sea when melting season comes to its end.

Today, most melt is perhaps located across the sub-glacial water-divide that takes any water falling through the ice ever deeper towards Greenland’s interior bowl. The dentures and crevasses on Greenland’s sub-glacial bedrocks and soils get filled with this water and ice above starts to float on top of these ponds of water that conveniently smooths the trajectory with witch the bottom of Greenland’s Ice Dome moves along the rock surface.

As ice is an extremely good insulator, summer-time heat that falls with melt water stays under the ice here virtually forever (at least for all practical purposes). Therefore, these are Accumulative Impact Moulins and Crevasses as heat builds up summer-after-summer and is the only process where the greenhouse effect reaches 100% heat-retention.

DOD or Army Corp of Engineers can create a project to pump water out from beneath the ice sheet thus accomplishing the multiple benefit of decreasing friction, reducing the spatial reach of the separating layer of water from between ice and rock and rooting the glacier once again. This would not only improve the ice sheet anchorage, or mooring, to the bedrocks, but pumping water out would, in theory, also help remove the ground heat as well.

TRANSFORMATION OF POTENTIAL ENERGY OF MELT WATER TO MECHANICAL ENERGY

As sad as it might be to think melting Greenland ice as destabilising; We must not forget that we have experienced the same processes in the distant geological past.

When moulins and crevasses drain and generate, thin but, high-speed water jets under the ice dome, these water jets then cause the dreaded cavitation process which pulverizes bedrocks, and which has created a lot of the sandy beaches we all play at. And plenty of inert materials for the builders and the construction trade.

On other occasions, large layers of water penetrate suddenly through ice when large melt water lakes drain themselves very suddenly through the entire height of the Greenland ice sheet. The plucking takes place where the rapidly falling water meets the bed rocks at the bottom of ice. Instead of pulverising the bed rocks into fine-grain sands, the massive blasts of highly pressurised water lifts the entire ice sheet up much more than the steady creeks collecting and creating a floating ice cap as they are originating from a moulin with steady water input. The ice rises and a tall temporary cavern allows a thick blanket of the fast-moving water create a blast of rapidly moving flash-floods under the Greenland Glacier. The plucking is a rapid erosion force that quickly creates immensely large rocks that are often seen as post-ice age huge boulder piles or fields. The boulders often get stuck again into the bottom of the ice sheet when the temporary cavern spreads further out and the glacier thins away. These boulders can then be carried away much further than by any stream of water alone could quickly do. These huge boulders created by plucking under ice sheet may become ice-embedded and can be themselves transported hundreds of miles away by the sliding ice sheet.

Sometimes underwater tornado-like currents form under ice that leads to the kolking, which (just like tornado in the air) can lift and remove large chunks of the underlying material. Persistent turbulent currents under the ice sheet create the giant’s cauldrons and potholes (water pouring via moulins over extended periods of time, when drainage out is stable, can create localised plucking and kolking which drill these formations into hard granitic rocks).

Where ice crashes without any pressurised, high-speed water jets, like at the terminus of glaciers (or sides of a glacier), moraine forms from the abrasive mixture of soil and moraine that is slowly pushed forward into piles, or ridges, by the moving glaciers.(1)

IMPORTANCE OF SUB-GLACIAL LAKES OVER SPILLING WITH ICE SHEET FAILURE AS RESULT

So, when Greenland Ice Sheet collapses by the various processes? The accumulation of melt water by the Accumulative Impact Moulins and Crevasses is absolutely vital factor.

As more and more warm water pours in and warms ice sheet’s base cumulatively, further melt is ever easier by the Accumulative Impact Moulins pouring water in year-on-year. A situation would eventually arrive where Greenland’s Ice Dome base below sea level would all be turned into water, topped by ice. But the melt water lake cannot indefinitely thicken under the ice sheet without this system becoming rapidly chaotic and unstable.

The melt water lake within Greenland’s interior depression bowl, under the ice dome, need not reach sea table, nor exceed it, for the “ice sheet thrust” to occur: the bottom of Greenland’s ice dome will never sail atop a flat water table. If it were so, we would be safe and have several centuries to await for the instability to occur if all bottom half of ice had to melt to the level of sea table and this flat pool of water was topped by the remaining ice sheet neatly floating on a flat water surfaces as if occurring on open seas or lakes. No.

As the melt water is created from the bottom of ice sheet, the edges of this subglacial melt lake water is pushed very rapidly and firmly up, the surface of this subglacial lake bent along its edges inside Greenland interior bowl, along the interfaces of rock and ice.

Just like the ice bergs float in open water with only the smallest part of approximatelly 1/8 visible above the sea’s surface, the glacial melt process isn’t visible much to us in a reverse phenomenon. Once started, the rise of water table on this sub-glacial melt-water lake (that is squeezed between bed rock and ice) rises extremely rapidly along the ice-rock interface as the layer of water is not thick, but spread out in three dimensions along the interface. Very soon, this melt water lake surface reaches and exceeds the sea level when the final ice sheet slide out occurs.

What once may appear that there is huge amount of depth left in this thin melt water lake under the ice sheet, it is very quickly pushed up to sea level and above on the very limited space of the ice-rock interface before the ice sheet land containment failure finally occurs.

This is not a matter of centuries, not even years, but coud be a season or even a week or a day…
Because once the melt-water warmed Greenland ice sheet starts a rapid melt water accummulation along its very bottom… the tipping point will have been exceeded.
Literally tipping and sliding the largest Ice Cap known to man (above land) into the sea will cause a replay of Noah’s floods in the post Biblical Times.
Could be tonight.
Or even…
Today

PS: The drainage of melt water under the glacier, should help. I have not yet come up with appropriate mechanism of how to pump the water out in large enough quantities…
But this is an engineering problem that can be solved with concerted professional effort.

When I was in Greenland with Jane Lubchenko as spokesmen for the Environmental Parliament in the symposium “Arctic – Mirror of Life” that was convened by H.E. Kofi Annan and H.E. Jose Manuel Barroso, the native Indians and the resident Greenlanders came to tell us, that they felt their ice age is ending. But there are many ways for it to end. But to them it appeared that most of the ways the Greenland Ice Cap will end, seemed to be rather fast and speedy.Based partly on the local Indian cultural histories and partly in science and geological evidence.

There is no more important issue than the ice in Greenland as there is the impending switch-over to post-sea ice conditions taking place in the Arctic Ocean nearby: even the winter sea ice is much reduced (due to the thin ice being as easily compressible into pack ice as a deflating harmonica folds upon itself).

In the past the old multi-year sea ice did not pile-up so easily as this year’s thin sea ice. I remain of the opinion that 2010 might see Arctic sea ice gone by the end of summer due to the ice pile-up, larger waves &, sea winds scattering ice onto open and warmed-up seas.

Perhaps much more important than the melting volume in Greenland is where it occurs:

If the ice melts in Greenland’s periphery, all melt water (and heat in it) drains away quickly when the melt season ends. (These are seasonal-impact moulins and crevasses.) However, now the melting occurs much higher on the ice dome where the sub-glacial ground surface inclination turns inward and where the melt water sinks ever deeper into Greenland’s interior depression, filling the uneven dentures and crevasses by water. This lifts up ice dome as it floats above rough surfaces: mooring to the ground is quickly replaced by sailing on the ground. Mooring of the ice then located at the downstream obstacles only.

As ice is a very good insulator (Greenlanders, build well insulated snow-houses) the heat that is taken down with the water that pours in through moulins and crevasses takes heat with it for ever. (These are accumulative-impact moulins and crevasses – a greenhouse effect with 100% heat retention as most of this water takes thousands of years to make its way ultimately towards and out of Melville Bay depression in North West Greenland.)

The tipping point in Greenland’s ice mooring has been crossed as each year a new gulp of warm water is added to the base of ice sheet (since the start of accumulative impact moulins and crevasses started to form at higher altitudes in Greenland the last few years).

Because of this loosening of the footing of Greenland’s ice dome by melt water incursion, we monitor the coastal barrier stability at Melville Bay by GPS meters in case the increased pressure destabilises this section and “ice sheet thrust” re-occurs to break ice loose here.

We are also looking at sub-glacier high velocity water jets that cause cavitation, plucking and kolking under the ice shelves that are feeding turbidic mud and rock flows into Melville Bay basin and how these cause fast erosion on the rock barrier holding back the ice sheet.

We either fly in with military helicopters from Thule-Pituffik base in extreme North West, or use civilian aircraft from Ilulissat airport that is south from Melville Bay. We think there are several sections that are already in a macro-scale movement towards the sea and our aim is to capture this movement by GPS. We aim for an amicable settlement with the Danish authorities and co-operation (rather than deploy citizen cover journalists to observe this).

I am almost certain that if we do reach agreement over this matter soon as it is no interest of the Danish government to try to stop our United Nations’-based enquiries even if they think Greenland ice sheet land containment failure by “ice sheet thrust” at Melville Bay is no risk.

We also have a great deal of support internally in Greenland to challenge the idea that the ice melts 15,000 years or 1,000 years, and support from the World Indigenous Nations that the sea floods do occur suddenly as the ice domes loose their footing and slide into the seas.

We do hope the Indians are wrong and the Western idea of the ice sheets melting peacefully in situ over many millennia would be right. But for us Greenland appears as the snow roof of the world and when spring comes, only few drops of water comes out and then the whole snow sheet falls down from roof.

Thus, if the ice age in Greenland ends soon, it is sad to see us so unprepared for this big flood and associated rapid “the Last Dryas” cooling as the United Nations’ General Assembly was warned by the First Nations of the North America under the auspices of World Indigenous Nations Summit as its closing plenary investigation request plea for the UN.

Let’s see if the Danish have guts to delay our geophysical experiments further, although no one wish to see the indigenous people’s idea (or fear) of “ice sheet thrust” occurring to bring the ice age in Greenland to its end: less than 1% melts, more than 99% slides out.

It is an issue that needs to be discussed with the Top levels of DARPA and DOD. They understand the threat and the possible scenarios for Mitigation.

We have been lobbying the Administration, but just with Lubchenco and Holdren and others… who side with the prevailing Victorian era wisdom of the geologists and Earth scientists who think this Greenland Ice Cap melting event will take place at glacial speeds of hundreds of years, and therefore no need to worry right now.

However we also [know that] glaciers can move faster than lightning… and unannounced. And we know that Black Swan events also happen suddenly. And most importantly they always catch us unawares….

However there are defences and mitigation technologies available if we decide to act now. We can document the process and investigate deeply and if found to be warranted – then we can build Dams and defences and river drainages and many more smart and effective glacier movement slow down mechanisms….

However : Who can understand and deal with this? Only the professional security forces, the army, the NOAA and maybe the Royal society. However the Army Corp of Engineers can actually do things. They are the only ones who can do projects of the scale of geoengineering needed urgently. A scale of sophistication and engineering excellence to create underglacier melt water river drainages and re-secure the foundations of the Glacier to slow down the eventual slide out.

Please keep in mind that a 2ºC warming in the temperate zones can translate to up to 15ºC in the Arctic and the Greenland zone.

And then….
The Floods

Regards

Pano Kroko
Environmental Parliament.

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