From the Potsdam Institute for Climate Impact Research (PIK), home of Schnellenhuber.
Uncorking East Antarctica yields unstoppable sea-level rise
The melting of a rather small ice volume on East Antarctica’s shore could trigger a persistent ice discharge into the ocean, resulting in unstoppable sea-level rise for thousands of years to come. This is shown in a study now published in Nature Climate Change by scientists from the Potsdam Institute for Climate Impact Research (PIK). The findings are based on computer simulations of the Antarctic ice flow using improved data of the ground profile underneath the ice sheet.
“East Antarctica’s Wilkes Basin is like a bottle on a slant,” says lead-author Matthias Mengel, “once uncorked, it empties out.” The basin is the largest region of marine ice on rocky ground in East Antarctica. Currently a rim of ice at the coast holds the ice behind in place: like a cork holding back the content of a bottle. While the air over Antarctica remains cold, warming oceans can cause ice loss on the coast. Ice melting could make this relatively small cork disappear – once lost, this would trigger a long term sea-level rise of 300-400 centimeters. “The full sea-level rise would ultimately be up to 80 times bigger than the initial melting of the ice cork,” says co-author Anders Levermann.
“Until recently, only West Antarctica was considered unstable, but now we know that its ten times bigger counterpart in the East might also be at risk,” says Levermann, who is head of PIK’s research area Global Adaptation Strategies and a lead-author of the sea-level change chapter of the most recent scientific assessment report by the Intergovernmental Panel on Climate Change, IPCC. This report, published in late September, projects Antarctica’s total sea level contribution to be up to 16 centimeters within this century. “If half of that ice loss occurred in the ice-cork region, then the discharge would begin. We have probably overestimated the stability of East Antarctica so far,” says Levermann.
Emitting greenhouse-gases could start uncontrollable ice-melt
Melting would make the grounding line retreat – this is where the ice on the continent meets the sea and starts to float. The rocky ground beneath the ice forms a huge inland sloping valley below sea-level. When the grounding line retreats from its current position on a ridge into the valley, the rim of the ice facing the ocean becomes higher than before. More ice is then pushed into the sea, eventually breaking off and melting. And the warmer it gets, the faster this happens.
Complete ice discharge from the affected region in East Antarctica takes five thousand to ten thousand years in the simulations. However, once started, the discharge would slowly but relentlessly continue until the whole basin is empty, even if climate warming stopped. “This is the underlying issue here”, says Matthias Mengel. “By emitting more and more greenhouse gases we might trigger responses now that we may not be able to stop in the future.” Such extensive sea level rise would change the face of planet Earth – coastal cities such as Mumbai, Tokyo or New York are likely to be at risk.
Article: Mengel, M., Levermann, A. (2014): Ice plug prevents irreversible discharge from East Antarctica. Nature Climate Change (online) [DOI: 10.1038/NCLIMATE2226]
Weblink to the article: http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2226.html
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Meanwhile…back in reality
Antarctic Sea Ice Blows Away Records In April
By Paul Homewood
Antarctic sea ice continues to set new records, with extent in April at the highest since measurements began in 1979.
http://nsidc.org/data/seaice_index/index.html
Ice extent has also been above last year’s already high levels for most of this year.
http://nsidc.org/data/seaice_index/index.html
Meanwhile, both GISS surface and UAH satellite datasets show the Antarctic has been much colder than usual recently.
Full story:
I guess that when the climate change finally dies it’s natural death there will be no shortage of new authors of horror fiction and fairy tales as warmist climate ‘scientists’ seek other employment where their talents for invention and fiction can be redeployed.
Meanwhile…back in reality
please try to understand that we are cooling from the top (latitudes) down
http://oi40.tinypic.com/2ql5zq8.jpg
It has been cooling significantly in Alaska, at a rate of -0.55K per decade since 1998 and -1.05K per decade since 2000 (Average of ten weather stations there).
Lets pretend for a moment that the article was spot on.. pretend that sometime within the future a change will occur on Earth effecting the Antarctic that will take 5000 to 10,000 years to complete. Knowing that Antarctica was not always under ice should we not consider the fact that Antarctica will not always stay under ice? Lets not quibble about cause but point out the stupidity of the thought process that claims the Earth should remain a static unchanging place and that any evolution is dire or disastrous. Adapt or die. If you cannot adapt, you go extinct. I should hope in 10k yrs we will be a smarter race and not accept sky is falling sheeple r us thinking.
Im so sick of the agw movement. They are raping the earth in the name of the greater good, their bottom line and their deep pockets. Every solar farm that completely kills the acreage it occupies, Every wind farm that clear cuts the land and has to employ caretakers to just pick up the corpses. Every child who starves because we put food in our fuel tanks is an affront to people who really wish to be good caretakers of this Earth. ENOUGH!
Or in 5000 years sea levels could be 100 metres lower because of glaciation. Whatever happens I’m sure our descendants 5000 years from now will cope with it just fine.
Where an earth do they get their inspiration?
http://wattsupwiththat.files.wordpress.com/2014/01/mawson_irony.jpg
pkatt says:
May 5, 2014 at 12:29 pm
Every wind farm that clear cuts the land and has to employ caretakers to just pick up the corpses.
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Germany plans to build 60,000 new wind turbines — in forests, in the foothills ……….
60,000 turbines x 45 cement mixer lorries per turbine x 20 tons of cement per lorry.
= 54,000,000 tons of cement in pristine countryside.
every wind farm is a city of concrete.
Very smart concoction, if, if, if it gets colder, you simply run the perpetual alarm model in reverse, appeal for more funds to prevent the unpreventable, Pots – damn genius!! The oceans will recede so far, commerce will fail, The great Barrier reef will become cliff tops, 50,000 polar bears will have to be relocated, the sky might fall, whatever, and the best part I wont be around to be held to account IF it doesn’t happen.
There is a cyclic pattern of climate obsessed people circulating between focal points of climate apocalypse. When focal point of fear “A” becomes thoroughly debunked, the obsessed move on to “B”, and so forth until enough time elapses for obsessive focal point “A” to have dropped out of popular memory, and then the climate obsesed will revisit “A” again, in an apparently endless cycle.
The number one cause of alarmism is publication requirements for retention and promotion. This counts.
(*¿*)
Oh the pain!
The models have taken over peoples brains again.
The rest of this comment will sum up the accuracy of virtually all model output.
They’re desperate. It’s all collapsing.
richard says:
= 54,000,000 tons of cement
= Roughly the same tonnage of planet-anihilating CO2, from production of the cement alone. By my hiroshomometer, that is the equivalent of at least 97.3 million hiroshima bombs going off, which is a travesty.
hunter says: May 5, 2014 at 12:55 pm
Thermophobia has spread so wide that no wonder the leading actors have been awarded with Nobel price and Oscar.
The UN, the World Bank, the Multilateral Development Banks and managers of the Climate Investment Funds need these kinds of doomsday scenarios wrapped up in scientific papers to justify the current and proposed enormous investment in the global ‘green economy’.
In 2012 global investment in ‘climate change’ was USD $359 billion. Of this, $135 billion, 38% was public finance and $224 billion, 62% was private finance. A similar sum was invested in 2011. Yet this is considered too little:
“The International Energy Agency projects that an additional investment of USD 5 trillion is required by 2020 for clean energy alone, to limit warming to two degrees Celsius.
“The World Bank projects we are on a path to four degree Celsius warming…”
http://climatepolicyinitiative.org/press-release/climate-change-investment-totals-usd-359-billion-worldwide/
Col Mosby says on May 5, 2014 at 10:05 am
“Why don’t we just build a REALLY big cork? Hey, I can be just as dumbass. Any day.”
= = = = = = = =
I have put in for the funding as I have a big enough basement to build/construct a “suitable” cork. (Top secret: I’ll be using 4 inch thick ply-wood) – You “wanna” come in at the start of this venture – and thus make $ £ millions? Just send a “fiver” to Santa’s grotto @ur momisugly the North Pole, – Oh, I forgot, that is the opposite end to Antarctica. (But the “people” are stupid so no one will notice)
Or alternately if you want to become very – very rich; then fleece the taxpayers. Just like somebody called Al did. His full name is Ali Baba, of course.
Don Easterbrook says:
May 5, 2014 at 10:53 am
” so the miniscule rise of CO2 from ~300 to 400 ppm is an increase of only 0.010 % ”
..
Don, going from 300 to 400 is an increase of 100 ppm.
100/300 = 33%, not 0.010%
Here is what thyat irresponsible agency known as the IPCC which is prone to gross exaggeration says about Antarctic ice melt:-
“The Antarctic Ice Sheet is projected to remain too cold for widespread surface melting, and to receive increased snowfall, leading to a gain of ice. Loss of ice from the ice sheet could occur through increased ice discharge into the ocean following weakening of ice shelves by melting at the base or on the surface. In current models, the net projected contribution to sea level rise is negative for coming centuries, but it is possible that acceleration of ice discharge could become dominant, causing a net positive contribution. Owing to limited understanding of the relevant ice flow processes, there is presently no consensus on the long-term future of the ice sheet or its contribution to sea level rise.”
(Climate Change 2007: Working Group I: The Physical Science Basis AR4)
As a bonus I include this question and answer:-
There is no doubt that should the Greenland ice cap melt completely there will be up to approx. 6 meters of sea level rise. What is the time period given by the IPCC in which the Greenland icecap is expected to completely melt?
The period ascribed to this event in AR4 is “millennia”, (Being the plural of “millennium”) which means at least two thousand years. (Climate Change 2007: Synthesis Report)
“Except for remnant glaciers in the mountains, the Greenland Ice Sheet would largely be eliminated, raising sea level by about 7 m, if a sufficiently warm climate were maintained for millennia” (Climate Change 2007: Working Group I: The Physical Science Basis AR4)
In AR5 I see they have quietly changed this to “over a millennium or more “ (AR5 Summary for policy makers P 27)
Interesting that they have almost knocked a thousand years off the melting time with some clever wording although they do not appear to be forecasting any increased rate as a result of any recent “scientific” research.
In fact the whole thing is fallacious BS. If the IPCC had anything to hang melting ice in Antarctica on its pretty obvious they would have used it. The fact they don’t means that the increasing of the Antarctic ice is too irrefutable even for them!
Of course I believe that the whole AGW thing is BS and more and more people are seeing this. But however the seed has been laid for Agenda 21 and while we are running around refuting the IPCC and their exaggerating cronies and “do gooders”, Agenda 21 is infiltrating our education, local government and legislation.
Check my blog and give me your opinion by leaving a message.
Roger
http://www.thedemiseofchristchurch.com
Thanks, PIK, for the warning. /sarc
You find so many catastrophic tipping points that would make our existence so improbable it is impossible. We know we are not in the Garden of Eden, but this escalating horror show is way over the top.
“Meanwhile…back in reality”, I have some extra ice for sale, with delivery from the north or the south, at your convenience.
blueice2hotsea says:
May 5, 2014 at 11:33 am
I can’t can’t find the old reference to those inland rookeries. Worse, I may have mixed-up with GREENLAND. In either case, I apologize,.
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No need to apologize! There were e.g. big sea elephant rookeries during the Holocene Climate optimum on coast regions in Antarctica where today it is much to cold and icy for rookeries. See here:
http://www.abc.net.au/science/articles/2009/08/04/2645375.htm
This means, Antarctica was for thousands of years much warmer than today but nothing dangerous did happen…
So just enjoy this funny and hilarious joke paper from the “Masters of Geo-Fantasy” in Potsdam… 🙂
A bit off topic, but not entirely…..
I was watching an episode of Cosmos: A Space Time Odyssey last night, with Neil Tyson narrating. The Lost Worlds of Planet Earth, Episode 9, I believe. During the show Mr. Tyson was discussing the current Holocene interglacial and stated (to my best recollection) “… and this (Holocene) interglacial has another 50,000 years to run.” That gave me pause…… Did others watch this episode and perhaps note this assertion also?
My understanding is that interglacial warming periods average about 11,000 years in length, with minimum at about 7,000 years and maximum at about 17,000 length, to the best of our current knowledge. Our current Holocene interglacial is estimated to be 11,700 years in duration now, providing an estimated starting date for glaciation onset from ‘any day now’ to ‘somewhere in the next 5300 years’.
Perhaps I mis-heard what Tyson said ( but I don’t think so). Or I am mistaken about the estimated 11,000 year average length of interglacials? Is there any basis for a prediction that the Holocene has another 50,000 years of duration, before we slide back into a 90,000 year long average glaciation period?
Mac
Thanks, Mac the Knife, I thought I might have dozed off for a second and a nightmare replaced the end of the show in my mind. Maybe I just had switched to “The Horror Channel”?
Maybe, in that empty chamber in “The Hall of Extinctions” will be the cultures that believe in the CO2 scare.
The weight of all that ice compresses the landmass. The area around the Great Lakes is still decompressing (rising) thousands of year after the glaciers from the last ice age melted. My question for Antarctica is — Suppose the ice is melting, how much will the land rise and how fast will it rise? Fast enough for the rim to rise above sea level and reduce the danger?
My question is entirely academic, of course, as the doomsday scenario above just ain’t happening.
I saw this earlier, but decided a well-referenced comment would take too much time away from my current research project. In the process of that research over the last few hours, I was re-reading a paper I had already made highlights in. Interestingly enough, it just happened to contain the information I was going to have to dig up for a properly offered comment here. The paper is here:
http://www.researchgate.net/publication/40693968_Probabilistic_assessment_of_sea_level_during_the_last_interglacial_stage/file/e0b4951753e120f4c7.pdf
PROBABILISTIC ASSESSMENT OF SEA LEVEL DURING THE LAST INTERGLACIAL STAGE, Robert E. Kopp, Frederik J. Simons, Jerry X. Mitrovica, Adam C. Maloof & Michael Oppenheimer, Vol 462| 17 December 2009| doi:10.1038/nature08686.
From the Discussion (Conclusions) section:
“The results of our analysis support the common hypothesis that LIG (Last InterGlacial) GSL (Global Sea Level) was above the current value, but contrary to previous estimates, we conclude that peak GSL was very likely to have exceeded 6.6m and was likely to have been above 8.0 m, though it is unlikely to have exceeded 9.4 m. The LIG was only slightly warmer than present, with polar temperatures similar to those expected under a low-end ~2C warming scenario. Nonetheless, it appears to have been associated with substantially smaller ice sheets than exist at present. Achieving GSL in excess of 6.6m higher than present is likely to have required major melting of both the Greenland and the West Antarctic ice sheets, an inference supported by our finding that both Northern and Southern hemisphere ice volumes are very likely to have shrunk by at least 2.5 me.s.l. (meters equivalent sea level) relative to today.”
You’d have to be a caveman not to get all of that. Not only were sea levels much higher than present during the Eemian, polar ice volumes would have been much lower, and the WAIS was indeed indicated as an agent provocateur.
It’s happened before. In fact the vast majority of evidence indicates it most recently happened at the end of the last interglacial. Not to mention throughout most of MIS-11 (details here http://wattsupwiththat.com/2012/03/16/the-end-holocene-or-how-to-make-out-like-a-madoff-climate-change-insurer/).
A Dead Heat to the end of the present interglacial. “We” are, in fact, competing with events that have occurred at least two documented times before. “Our” IPCC AR4 “worst case, business as usual” +0.59 M amsl sea level rise by 2099 is only 9% or the low end estimate of +6.6M amslfor the end-Eemian in this paper! Just over 6% if we use the +9.4M amsl, “we” score just over 6%.
That’s a huge anthropogenic “signal” to natural end extreme interglacial climate “noise”!!!
And what about speed of sea level rise. Kopp et al 3009 provide this:
“Our results suggest that during the interval of the LIG when sea level was above 210 m, the rate of sea level rise, averaged over 1 kyr, was very likely to have reached values of at least about 5.6m kyr but was unlikely to have exceeded 9.2m kyr. Our data do not permit us to resolve confidently rates of sea level change over shorter periods of time.”
Nature wins again. That’s +0.56m/century on the low end and +0.92m/century on the high end. And “we” are betting the farm on +0.59m/century.
The only known substitute for intelligence is stupidity.
Consider the following proof:
“Recent research has focused on MIS 11 as a possible analog for the present interglacial [e.g., Loutre and Berger, 2003; EPICA community members, 2004] because both occur during times of low eccentricity. The LR04 age model establishes that MIS 11 spans two precession cycles, with 18O values below 3.6 o/oo for 20 kyr, from 398-418 ka. In comparison, stages 9 and 5 remained below 3.6 o/oo for 13 and 12 kyr, respectively, and the Holocene interglacial has lasted 11 kyr so far. In the LR04 age model, the average LSR of 29 sites is the same from 398-418 ka as from 250-650 ka; consequently, stage 11 is unlikely to be artificially stretched. However, the June 21 insolation minimum at 65N during MIS 11 is only 489 W/m2, much less pronounced than the present minimum of 474 W/m2. In addition, current insolation values are not predicted to return to the high values of late MIS 11 for another 65 kyr. We propose that this effectively precludes a ‘double precession-cycle’ interglacial [e.g., Raymo, 1997] in the Holocene without human influence.”
Lisiecki and Raymo, 2005, A Pliocene-Pleistocene stack of 57 globally distributed benthic D18O records, Paleoceanography, Vol. 20, PA1003, doi:10.1029/2004PA001071. http://www.350.me.uk/TR/Hansen/LisieckiRaymo_preprint.pdf
Without human influence…….. You mean like CO2? As in we would now be in glacial inception were it not for CO2? And you want to remove it, right?
Did you bump your head?
“That’s a huge anthropogenic “signal” to natural end extreme interglacial climate “noise”!!!”
Meant to say “That’s a huge anthropogenic “signal” to natural end extreme interglacial climate “noise”ratio problem!!!
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Of course the myth is that our paltry “trigger pull” now could trigger anything that needs to be stopped. Or that we even could even if we had a time machine. (If we could erase the Industrial Revolution, what do we have other than theories that the weather or climate today would be much different?)