A Terrifying Sea-Level Prediction Now Looks Far Less Likely
But experts warn that our overall picture of sea-level rise looks far scarier today than it did even five years ago.
ROBINSON MEYER
JAN 4, 2019
One of the scariest scenarios for near-term, disastrous sea-level rise may be off the table for now, according to a new study previewed at a recent scientific conference.
Two years ago, the glaciologists Robert DeConto and David Pollard rocked their field with a paper arguing that several massive glaciers in Antarctica were much more unstable than previously thought. Those key glaciers—which include Thwaites Glacier and Pine Island Glacier, both in the frigid continent’s west—could increase global sea levels by more than three feet by 2100, the paper warned. Such a rise could destroy the homes of more than 150 million people worldwide.
[…]
It is a reassuring constraint placed on one of the most alarming scientific hypotheses advanced this decade. The press had described DeConto and Pollard’s original work as an “ice apocalypse” spawned by a “doomsday glacier.” Now their worst-case skyrocketing sea-level scenario seems extremely unlikely, at least within our own lifetimes.
[…]
Yet their work—and the work of other sea-level-rise scientists—still warns of potential catastrophe for our children and grandchildren. If every country meets its current commitment under the Paris Agreement, the Earth will warm about 2.7 degrees Celsius by the end of the century compared with its pre-industrial average. In their new research, DeConto and his colleagues say that there’s a tipping point, somewhere between 2 and 3 degrees Celsius of temperature rise, after which the West Antarctic Ice Sheet will slip into rapid and shattering collapse.
[…]
The new results inform one of the biggest outstanding questions—and most fervent debates—concerning how climate change will reshape our world: How much will the seas rise, and how fast will that upheaval occur? DeConto and several other American glaciologists—including Richard Alley, a professor at Penn State and a co-author of the new research—represent something like the vanguard of that discussion. They champion an idea called “marine ice-cliff instability,” or MICI, which maintains that West Antarctic glaciers will eventually crumble under their own weight. By the middle of next century, they warn, this mechanism could send ocean levels soaring at a rate of several feet per decade. For reference: Along the U.S. East Coast, the Atlantic Ocean has risen by only about a foot over the last 12 decades.
While “marine ice-cliff instability” might be clunky, the idea is cinematic.
[…]
Other researchers find this possible future somewhat fantastic. “We, as European modelers, are slightly more skeptical of the marine-cliff idea,” Frank Pattyn, a glaciologist at the Free University of Brussels, told me. “It has not been observed, not at such a scale.”
[…]
There is only one place in the world where MICI is definitely happening: Jakobshavn Glacier, on the west coast of Greenland.
[…]
Alley, the Penn State glaciologist, addressed the sapphire-colored elephant in the room immediately after taking the dais. As he sees it, it’s just common sense that Antarctic glaciers will develop problematic ice cliffs.
[…]
In this scenario, he warned, “We will not have analogues … We are going to move outside the instrumental data that we use to calibrate our models.”
Then came the skeptics. Dan Martin, a computational scientist at Lawrence Berkeley National Lab, argued that his and his colleagues’ work showed that ice cliffs might simply be a product of running a computer model of ice physics at a too-low resolution. Eric Larour, a physicist at NASA, presented the possibility that the physics of the Earth itself might slightly counteract some rapid ice-cliff collapse. As the ice sitting on West Antarctica melts, the bedrock below it will bounce back up.
“When ice melts or thins, you can think that the Earth [below it] is going to rebound,” he said. That bedrock will rise, lifting the glacier partly out of the water. Such a mechanism could buy humanity some time, he said, giving us a “23 to 30 year delay” in the total collapse of West Antarctica. This effect might hold off the collapse of West Antarctica until 2250 or 2300, but then the ice sheet would disintegrate as fast as ever.
The meeting arrived at no clear conclusion.
[…]
MICI remains a young idea, first proposed only six years ago. It need not be rejected simply because scientists haven’t arrived at hard conclusions yet, Fricker, the Scripps glaciologist, said.
[…]
“It might not happen,” Fricker said. “But if there’s a chance that it could happen, then shouldn’t you involve that in your planning? If you’re hosting a picnic and it might rain, you don’t necessarily move the whole event, but you probably do make a Plan B. If you’re planning a city … you might as well keep this in the back of your mind.”
We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.
I thought about submitting a letter… But I doubt they would want to hear what I think about this article. Robinson Meyer is a twenty-something year old staff writer for The Atlantic with a 2013 B.A. in music.
I love this bit: “Then came the skeptics.” Why were they even invited? I thought they had all been banished from the AGU. How dare they throw cold water on a perfectly good model-derived catastrophe… /Sarc.
Marine ice cliff instability (MICI) “has not been observed, not at such a scale,” “might simply be a product of running a computer model of ice physics at a too-low resolution,” ignores post glacial rebound, couldn’t occur before ” until 2250 or 2300″… Yet “the idea is cinematic,” “it’s just common sense that Antarctic glaciers will develop problematic ice cliffs” and something we should plan for…
Figure 1. AEUHHH????
How can you plan for something that’s never been observed? May not ever happen? Won’t happen for 200-300 years, if it does happen? What’s the point in even keeping “this in the back of your mind.” No one with this in the back of their mind today will be alive in 2250. Their children won’t be alive. Their grandchildren probably won’t be alive. In 2250, we can just let Star Fleet take care of this.
This comment was most reassuring…
“We will not have analogues … We are going to move outside the instrumental data that we use to calibrate our models.”
–Richard B. Alley, Penn State University
That will certainly be a relief to climate modelers, Their models will no longer have to be constrained by reality… Which won’t be much of a change. RCP8.5 is already unconstrained by reality.
Speaking of RCP8.5 and DeConto & Pollard, that’s how all of this got started…
Polar temperatures over the last several million years have, at times, been slightly warmer than today, yet global mean sea level has been 6–9 metres higher as recently as the Last Interglacial (130,000 to 115,000 years ago) and possibly higher during the Pliocene epoch (about three million years ago). In both cases the Antarctic ice sheet has been implicated as the primary contributor, hinting at its future vulnerability. Here we use a model coupling ice sheet and climate dynamics— including previously underappreciated processes linking atmospheric warming with hydrofracturing of buttressing ice shelves and structural collapse of marine-terminating ice cliffs—that is calibrated against Pliocene and Last Interglacial sea-level estimates and applied to future greenhouse gas emission scenarios. Antarctica has the potential to contribute more than a metre of sea-level rise by 2100 and more than 15 metres by 2500, if emissions continue unabated. In this case atmospheric warming will soon become the dominant driver of ice loss, but prolonged ocean warming will delay its recovery for thousands of years.
The “more than a metre of sea-level rise by 2100 and more than 15 metres by 2500″ is based on bad science fiction (RCP8.5)…
Figure 2. Figure 5 from DeConto & Pollard, 2016. “Large Ensemble model analyses of future Antarctic contributions to GMSL. a, RCP ensembles to 2500. b, RCP ensembles to 2100. Changes in GMSL are shown relative to 2000, although the simulations begin in 1950. Ensemble members use combinations of model parameters (Methods) filtered according to their ability to satisfy two geologic criteria: a Pliocene target of 10–20 m GMSL and a LIG target of 3.6–7.4 m. c and d are the same as a and b, but use a lower Pliocene GMSL target of 5–15 m. Solid lines are ensemble means, and the shaded areas show the standard deviation (1σ) of the ensemble members. The 1σ ranges represent the model’s parametric uncertainty, while the alternate Pliocene targets (a and b versus c and d) illustrate the uncertainty related to poorly constrained Pliocene sea-level targets. Mean values and 1σ uncertainties at 2500 and 2100 are shown.”
DeConto & Pollard essentially asserted that we are headed back to the Pliocene over the next few hundred years.
Not likely.
Figure 3. High Latitude SST (°C) From Benthic Foram δ18O (Zachos, et al., 2001) and HadSST3 ( Hadley Centre / UEA CRU via www.woodfortrees.org) plotted at same scale, tied in at 1950 AD.
We’ve already experienced nearly 1 ºC of warming since pre-industrial time. Another 0.5 to 1.0 ºC between now and the end of the century doesn’t even put us into Eemian climate territory, much less the Pliocene. Beyond that, who knows what will happen? While fossil fuels will dominate the energy mix for much of this century, does anyone really believe that better source of energy won’t be added to the mix between 2100 and 2250?
There is only one place in the world where MICI is definitely happening: Jakobshavn Glacier, on the west coast of Greenland.
Jakobshavn Glacier is not an MICI analogy for Antarctica. It’s not even an analogy for any other glaciers in Greenland.
Jakobshavn Glacier Calving Front Recession from 1850 to 2006
Visualizations by Cindy Starr Released on January 5, 2007
Jakobshavn Isbrae is located on the west coast of Greenland at Latitude 69 N. The ice front, where the glacier calves into the sea, receded more than 40 km between 1850 and 2006. Between 1850 and 1964 the ice front retreated at a steady rate of about 0.3 km/yr, after which it occupied approximately the same location until 2001, when the ice front began to recede again, but far more rapidly at about 3 km/yr. After 2004, the glacier began retreating up its two main tributaries: one to the north, and a more rapid one to the southeast.
These changes are important for many reasons. As more ice moves from glaciers on land into the ocean, it causes a rise in sea level. Jakobshavn Isbrae is Greenland’s largest outlet glacier, draining 6.5 percent of Greenland’s ice sheet area. The ice stream’s speed-up and near-doubling of the ice flow from land into the ocean has increased the rate of sea level rise by about .06 millimeters (about .002 inches) per year, or roughly 4 percent of the 20th century rate of sea level increase.
This image of the Jakobshavn glacier on 07/07/2001 shows the changes in the glacier’s calving front between 1851 and 2006. Historic calving front locations, 1851 through 1964, were compiled by Anker Weidick and Ole Bennike and are shown here in gray. Recent calving front locations, 2001 through 2006, derived from satellite imagery are show in colors. A distance scale is provided.
The calving lines were overlaid on a 2001 Landsat image.
This article was updated in July 2007 with a new image…
Figure 4. “The recession of calving front locations is shown over an image of the Jakobshavn glacier on 08/06/2006. Historic calving front locations from 1851 through 1964, compiled by Anker Weidick and Ole Bennike, are shown here in gray. Recent calving front locations, 2001 through 2006, derived from satellite imagery are show in colors.”
The glacier had indeed retreated from 2001-2006 after nearly 40 years of little movement. However, all of the retreat has occurred on the “floating ice tongue”…
Figure 5. “The calving front line from 07/07/2001 deliniates the area of floating icebergs from the solid glacial ice. Semi-transparent overlays identify the portion of the glacier which is over water (blue) and over land (tan).”
Jakobshavn Isbrae – Greenland Glacier Has Always Changed With The Climate
By News Staff | July 16th 2011
New research on Jakobshavn Isbrae, a tongue of ice extending out to sea from Greenland’s west coast, shows that large, marine-calving glaciers don’t just shrink rapidly in response to global warming, they also grow at a remarkable pace during periods of global cooling. *Glaciers change.
[…]
Jakobshavn Isbrae has been the focus of intense scientific interest because it is one of the world’s fastest-flowing glaciers, releasing enormous quantities of Greenland’s ice into the ocean. It is believed that changes in the rate at which icebergs calve off from the glacier could influence global sea level rise. The decline of Jakobshavn Isbrae between 1850 and 2010 has been documented, mostly recently through aerial photographs and satellite photographs.
“We know that Jakobshavn Isbrae has retreated at this incredible rate in recent years, and our study suggests that it advanced that fast, also,” said Jason Briner, the associate professor of geology at the University of Buffalo, who led the research. “Our results support growing evidence that calving glaciers are particularly sensitive to climate change.”
Figure 6. Jakobshavn Isbrae. (Wikipedia and Google Earth)
“Our results support growing evidence that calving glaciers are particularly sensitive to climate change.” Greenland’s climate is always changing… Always has and always will change… And the climate changes observed over the last few decades are not unprecedented. The Greenland ice sheet is no more disappearing this year than it was last year and it is physically impossible for the ice sheet to “collapse” into the ocean.
Each and every [fill-in-the-blank]-sized iceberg to calve off Greenland or Antarctica triggers the same alarmist nonsense and glacial junk science journalism. Glaciers are rivers of ice. They flow downhill. Downhill is generally toward the ocean, where they calve icebergs. Increased calving of icebergs is indicative of excess ice accumulation, not melting. Past glacial stages and stadials are associated with an increase in dropstones in marine sediment cores because icebergs calve more frequently when the source of ice is expanding.
From 1850 through 2006, Jakobshavn Isbrae’s floating ice tongue has calved into the ocean. Prior to 1850, glaciers had mostly been advancing since the end of the Holocene Climatic Optimum, a period known as “Neoglaciation.” While the retreat of Jakobshavn Isbrae’s floating ice tongue was punctuated with a prolonged hiatus associated with the mid-20th century cooling period, this process began at the end of Neoglaciation. The end of Neoglaciation was a “good thing”…
Figure 7. The Ice Age Cometh? Science News, March 1, 1975. Had Neoglaciation not ended, the “Ice Age” might just have “cometh,”
References
DeConto, Robert & Pollard, David. (2016). Contribution of Antarctica to past and future sea-level rise. Nature. 531. 591-597. 10.1038/nature17145.
Zachos, J. C., Pagani, M., Sloan, L. C., Thomas, E. & Billups, K. Trends, rhythms, and aberrations in global climate 65 Ma to present. Science 292, 686–-693 (2001).
“We are going to move outside the instrumental data that we use to calibrate our models.”
All climate models are doing that all the time.
since we at the warmest climate EVAH and “in a warming world” all climate model projections are extrapolations outside the calibration data. That is exactly the problem. They are tuned to reproduce the 1960=1990 climate record and project 100y or 200y beyond.
It is totally unscientific and meaingless to do that.
With the “Great Greening^ тм” and higher CO2, water will be conserved. Also, these aquifers can be recharged. The main problem with much of CAGW ‘science’ is the one way street the alarmists are on. The Sahara aquifers were charged during prevoous wetter greener periods. We may be fighting frigid climate and sea level drop by 2100.
This 2004 paper by Sturchio et al in Geophysical Research Letters may suggest otherwise…
I don’t know whether it has been challenged, but it seems clear that million year old Nubian groundwater is “freshwater” rather than saline. No idea whether it is potable, as the paper is silent.
Fortunately, their theatre is pretty empty these days.
John Robertson
January 5, 2019 10:27 am
I wonder if it is not time to get a “sciency paper” submitted to these foolish publishers.
I propose that as the continental plates slide under one another,that ground water will flood to the surface drowning all…for “recent studies” show there is far more water in the mantle than we previously suspected.
And everybody knows that dirt displaces water…
Therefore ;”We are all going to die” TM ( Some conditions apply, normal life expectancy excetera).
I confess to being bored with the constant bloviating of “Unspecified Doom” that passes for modern science.
So to spice things up a bit perhaps some creative myth making is in order.
Maybe we could have a big show every year and pass out Global Warming Edutainment awards?
This Spring, the first annual gala presentation of the Golden W.E.D.G.I.E Awards!
For the uninitiated twit on WUWT (me) It never occurred to me that calving of glaciers was more likely due to excess ice thanks to increased snowfall at the centre of the continent pressing down and expanding the ice sheet rather than warm sea’s melting the ice.
Mind you, I don’t believe for a moment 1.5C warming of the atmosphere, or land for that matter, could affect sea temperatures by any more than a minuscule fraction of a degree, if that.
My understanding is that the volume and density of water far outweighs any warming effect the thin, weedy atmosphere could have on SST’s never mind deep ocean temperatures.
I think I might be getting the hang of this AGW nonsense.
LMAO. Nope we won’t. Even if they rise by say 1 meter we will stay put (we=NL).
We already have dikes and spring tide storm flood protection which was designed to take on much, much, much higher levels of water from the North Sea. As in more than 10 meters (30 feet).
Oh no, it’s the “something might happen in the future and if we don’t prepare for it now we’re all doomed” mantra again. Don’t forget your great, great, great, children and while you’re at it send money to perpetuate research into the not so imminent, but catastrophic, results of your inaction.
“GRIM FORECAST A senior environmental official at the United Nations, Noel Brown, says entire nations could be wiped off the face of the earth by rising sea levels if global warming is not reversed by the year 2000.
San Jose Mercury News (CA) June 30, 1989 – 3F General News”
“Dr. Brown currently serves as President of the Friends of the United Nations”… Any friend of the United Nations is an enemy of individual liberty and prosperity!
Dr. Noel Brown is the former Director of the United Nations Environment Programme, North American Regional office. Dr. Brown holds a B.A. in Political Science and Economics from Seattle University, an M.A. in International Law and Organization from Georgetown University and Ph. D. in International Relations from Yale University. He also holds a diploma in International Law from The Hague Academy of International Law. He is a founding member of the Aspen Global Change Institute, the International Council for Local Environmental Initiatives, and Indigenous Development International.
Dr. Brown currently serves as President of the Friends of the United Nations. He is a fellow of the World Academy of Arts and Sciences, Chairman of the International Institute for Peace through Tourism and Chairman of the Rene Dubos Center for Human Environments. Dr. Brown has been a Visiting Professor at both U.S. and foreign universities, teaching on the subject of International Law and Organization, Government and Politics, and Environmental Management. He was a distinguished lecturer at the University of Victoria, British Columbia and an associate of the Queen Elizabeth Trust for Young Australians. Dr. Brown was the 1996 Leo Bloc Professor at the University of Denver and is currently the Director of training at the International Oceans Institute, Halifax, Nova Scotia, Canada. Dr. Brown serves on the Board of Directors of the Climate Institute, the Earth Communications Office, the Rainforest Alliance, MUSE, Film & Television, the Center for Resource Management, Global Education Associates, Trust for the Americas, the International Leadership Development Institute, Roots of Peace, International Sea-keepers Society, the Timbuktu Heritage Institute and Jamaica National Parks Trust Fund.
Dr. Brown has numerous awards acknowledging his service to the environment, including: the Lions Club Award, the Friends of the United Nations Award, the Gaia Award, and the Global Education Associates Award for Distinguished Service in Care of the Earth. Dr. Brown is a recipient of the 1998 World Academy of Arts and Science Award for Distinguished Public Service.
This is a satellite image taken 21 sept. 2018. Ignore the black “coast-line, it is obsolete. The current ice cliff is visible as the border between the white calved ice and the slightly darker glacier ice (it is darker because at this date someb melting is still going on).
Notice that it has hardly changed at all since 2007 when it reached the coast. It is still just a little “upstream” from the ice free cliffs north and south of the glacier. That is why maps of ice recession never get past 2007.
tty,
It still isn’t working. It takes me to EOSDIS World View (as does the first two lines), but the screen is black. Perhaps something got cut out at the edge.
Forgive me for exhibiting my ignorance but clarification would be appreciated.
According to the observations in this article, I understand that calving intruded into the glacier up to the lines marked as 2005/2006. Is that correct? In other words the estuary (for want of a better expression) was essentially ice free up to that point, perhaps in the summer? (I realise it may have been still packed with ice but it was free floating icebergs rather than connected glacial ice).
From the 2018 satellite observation you post, glacial calving now intrudes into the estuary only as far as calving in 2001 or so?
So in other words, the glacier has been growing for the last 12 to 13 years?
And whilst a crude description, is that close to the observations?
No, the estuary is and has alway always been full of calved ice (dead white in the satellite image). Jakobshavns isbrae drains more than 100 000 km^2 of the icecap so calving is always intense.
And no it hasn’t been growing for the last 12 to 13 years. It has been essentially stationary until 2017-2018 when it did grow slightly:
The fjord wasn’t ice-free… And still really isn’t ice-free. In 1851, the floating ice tongue extended all the way down to the 1851 calving line…
The Landsat photo is from 2001. Note the change at the 2001 calving line. The gray to the right of the calving line was a floating ice tongue. You can see some lineations parallel to the fjord. These are flow lines. Downstream of the 2001 calving line, the fjord is a mottled white color due to lots of floating chunks of ice. In 1851, the ice would have been gray with flow lines all the way down to the 1851 calving line. The calving lines subsequent to 2001 are superimposed on the floating ice tongue. A Landsat photo from 2006 shows that the gray area had moved about as far upstream as it could move…
Jakobshavn’s “iceberg” factory moved from the bottom to the top of the fjord from 1851-2006. Its rate of iceberg production will likely decline unless the ice mass in its drainage area increases faster than it is ablating.
” Its rate of iceberg production will likely decline unless the ice mass in its drainage area increases faster than it is ablating.”
Paradoxically the amount of ice “upstream” may actually increase once the glacier front is on land and no longer calving. It is well documented that glaciers that are melting rather than calving are significantly steeper than calving glaciers. This was noticeable in the NEEM ice-core where the enclosed air bubble suggest that the ice was about as thick or even slightly thicker than now at the center during the Eemian interglacial when the Greenland icecap was significantly smaller and probably mostly did not reach the coast.
Even NASA cutsoff Jakobshavn Glacier pictures to 2010.
You can see the slowdown, which is probably reversing now for the last 8 years, an inconvenient fact they are hiding, else they would show it.
Go to Bing Maps and navigate to the site.
Click on aerial view.
Gives a pic from 2018, ice is back to where it was in around 1964 in the center of the fjord.
And the pic is from mid summer…no ice in the water, melt pools on the surface of the glacier visible.
Hmmm…it may be that the views are doctored or masked.
Expanding out shows all of Greenland surrounded by water and the glaciers all have razor sharp cut off lines.
They are definitely masked. Ilulissat fjord is always chock-full of ice in summer. 10% of all Greenland icebergs come from it. Better use EOSDIS Worldview.
David and tty,
Has anyone offered up a coherent explanation for the tongue receding as it did prior to 2001?
More in particular the retreat in the 100 years between 1851 and 1953, when according to the IPCC’s mantra, anthropogenic CO2 did not have the impact it insists it has had since the 1950s?
Seems like a reasonable question to me.
What tty said, plus Neoglaciation ended around 1850. From the Holocene Climatic Optimum (~4-7 ka) glaciers were generally intermitenrly advancing. This interval is known as Neoglaciation.
The coldest part of the Little Ice Age (~1600-1700) was probably the coldest phase of the Holocene.
The Jacobshavn/Illulisat Isbree break-up point may have been advancing between 1965 and 2000, due to colder weather over Greenland. I have the Greenland temperatures up to 2005 here: http://www.ferdinand-engelbeen.be/klimaat/greenland_temp.html
Where the periode 1930-1950 was near as warm as after 2000.
Ferdinand, your photo tour makes me want to go there.
To me, the Bing maps seem to suffer the application of an algorithm that makes all the seawater the same color.
Look at Google Maps for 2019 pictures that show all the ice in the estuary. Note how the west end of the glacier seems to be calving into two streams of ice, one NE and one SE. That is much farther upstream than anyone has talked about.
John, as we like to travel to mountain ranges and cold regions, this indeed was one of the nicest experiences we had. The landscape can be compared to fjord regions all over the world, especially Norway (our favorite for over 10 times), but over an enormous area, even with much less inhabitants. No roads between “towns”, the longest road is between the capital and the airfield: about 7 km, with only one traffic light in the town and all of Greenland… Still they had Internet and smartphone connections in every distant village and music making and recording was – in 2000 – their favorite hobby. Quite expensive country as they have to import near everything with only one export product: fish (mainly halibut to Europe and deep sea shrimp to Japan). Denmark still provides 1/3 of their yearly budget, although they have practical independence. As far as I have seen on TV, there is coming some mining exploration in the mountains, thanks to the retreat of several glaciers.
Daughter Ann made a different tour with more heavy walks (like up to the inland ice) over the same period and did do dog sledging on Disko Island in the same region (Disko bugt/bay) as Ilulussat, all middle summer.
The Ilulissat Isfjord is an incredible view with a lot of noise from colliding icebergs. The speed the glacier/icebergs are traveling is one of the fastest in the world: average around 7 m per day. Camping is forbidden near the coast as icebergs may turn around when the downside melts away and may give a flood of several meters high.
The “feed” to the glacier indeed is much farther inland that the breaking point where the glacier breaks up in (large) pieces. The Landsat shows only the breaking point…
Incidentally “Ice Cliff Collapse” does occur. It happens when a glacier resting on sea-bottom reaches a water depth of about 500 meters. The 10% of the glacier that emerges above the surface then becomes mechanically unstable.
This is the basic reason the Antarctic ice doesn’t change very much between glacials and interglacials. It is basically as large as it can be. It is only when Northern Hemisphere glaciation lowers sea-level that it can extend a little further down the continental slopes.
Well, sometimes it does grow during interglacials too, because more snow falls, but then the central parts become thicker without much change along the periphery
I’m confused about this. It would seem to me that as the water gets deeper, at some point the glacier would start floating. Also, I thought it was above 100 m height that an ice cliff becomes unstable.
It depends on the thickness of the glacier if it is too thick to float it will extend seawards on the bottom until it becomes unstable. If it is relatively thin it will “float off” and form a shelf-ice or a glacier tongue. However this mostly applies to Antarctica. In the Arctic it is rarely cold enough for shelf ice or long glacier tongues to be stable (except occasionally in fiords). Even in the Antarctic shelf ice usually needs islands as “anchoring points” for stability.
The 500 meter figure is based on the maximum depth that icecaps have reached in the past based on studies of bottom morphology. I have occasionally seen “ice cliffs” higher than 50 meters, but they have all either been on land or in very shallow water.
Sara
January 5, 2019 11:44 am
Let me see.
1 – Ice is frozen water.
2 – Glaciers are ice.
3 – If glaciers were liquid, they’d be water.
4 – Gravity pulls on things, and they move down.
5 – Gravity pulls on glaciers, making them move toward a lower level.
6 – Gravity pulls on water making it flow toward a lower level.
7 – Gravity, ice and water are part of the natural world.
8 – The natural world is full of changes.
9 – Changes scare science peeps.
10 – Science peeps want money.
11 – Science peeps write scary stories about changes to get money.
Does anyone besides me see a scam going on here?
When these people make a projection that is anywhere from 50 to 250 years out, and most of them will NOT be around to see anything they predict, do they really believe they can sell this scam to anyone except those who are easily-panicked over everything?
Is there any way at all to stop this scam? This is becoming more and more ridiculous. By 2325, we may be living south of the Mason Dixon line with ice sheets 1.25 miles thick slowly moving southward. The Fertile Crescent may be green again. When the meteorology people can’t make an accurate forecast more than two days out, do these scammers really expect to be taken seriously?
As much as I would like to stop paying taxes it seems I can’t. Our incomes and bank accounts are remotely and automatically monitored by our respective taxation organisations (HMRC in the UK) and if my National Insurance number doesn’t equate to an income from a legitimate source then they will be down on me like a ton of bricks.
Our governments love the concept of cash free transactions, they despise physical money because they can’t track every penny you make and spend. They can, however, do so with ecommerce.
And whilst the ‘alternative’ economy makes up a fraction of most civilised countries economy, our governments will spend vast fortunes, far outweighing what they are combating, to ensure everyone is compliant.
HotScot, I am just about ready to go live in a yurt!
I’m in what you call ”pensioner” status – retired. My income may be modest, but I own my teensy-weensy home and the tax on it is also modest. My utilities charges are also modest. What I have is affordable on my income, and leaves a little room for fun.
What these creatures want to do is destroy that for no reason other than their own confounded greed.
Any time someone asks for a grant or largess from the government, out of tax money that should go for real-world things like repairing roads and bridges and emergency response teams and better weather forecasting – normal things that we need – but instead goes for a baloney program that is built on scare tactics, it is far past time to shut that nonsense down.
Everything I am seeing about so-called climate change “science” appears to be a scam, a fraud foisted on taxpayers for no real purpose beyond lining the pockets of people who contribute nothing of any use. If any of that nonsense improved weather forecasting, I would be less harsh, but it does not. When I look back at my own records and compare them with what Accuweather forecasts, the result is that Accuweather is consistently inaccurate for any forecasting beyond 2 to 3 days out.
Like I said, I’m about ready to move into a yurt.
Clyde Spencer
January 5, 2019 11:51 am
“Fricker said. ‘But if there’s a chance that it could happen, then shouldn’t you involve that in your planning? If you’re hosting a picnic and it might rain, you don’t necessarily move the whole event, but you probably do make a Plan B.”
What Fricker and others of his ilk don’t seem to realize is, that possibilities are not the same as probabilities. If the weather forecast is only 5% probability rain, one makes different picnic plans than if the probability is 95%! It is all these interminable “could, might, possibly, conceivable” that are inherently low probability but of unquantified probability that the alarmists milk. Hell, I MIGHT die tomorrow. That is a true statement. However, it doesn’t change the way I behave just because of the word “might.”
cerescokid
January 5, 2019 12:10 pm
David
Thank you for providing that extra information about Jakobshavn. I had read some background on it but frankly forgot what it was. But, as usual I believed it was reassuring and the hype not reconciling with the facts.
Each time I read about some of these apocalyptic papers and conferences, my first reaction is to ask the question “Aren’t there any adults in the room.”
Really, what happened to the old, calming hands who say let’s take our time and think this through. I guess they’ve been bullied into retirement.
And to pick up on a comment above, there are papers which address the issue of geothermal activity affecting Pine Island and Thwaites. If they want to have a more complete understanding of the dynamics that are at play they should spend more time on that kind of research. But would music majors be interested? Probably not.
Other researchers find this possible future somewhat fantastic. “We, as European modelers, are slightly more skeptical of the marine-cliff idea,” Frank Pattyn, a glaciologist at the Free University of Brussels, told me. “It has not been observed, not at such a scale.”
Then came the skeptics. Dan Martin, a computational scientist at Lawrence Berkeley National Lab, argued that his and his colleagues’ work showed that ice cliffs might simply be a product of running a computer model of ice physics at a too-low resolution. Eric Larour, a physicist at nasa, presented the possibility that the physics of the Earth itself might slightly counteract some rapid ice-cliff collapse. As the ice sitting on West Antarctica melts, the bedrock below it will bounce back up.
“When ice melts or thins, you can think that the Earth [below it] is going to rebound,” he said.
It doesn’t disprove it… But it renders it much less significant.
Martin557
January 5, 2019 12:32 pm
I like it when glaciers recede and somebody goes up there and finds the remains of some 500 year old tree at the new base of the glacier. It’s happened before. Kinda like people digging through perma-frost to see how the Vikings lived in Greenland when there wasn’t perma-frost to dig through.
That is why trees etc revealed by receding glaciers are so seldom mentioned by the climatariat. While incontrovertible proof that the glacier hasn’t been this small for X years (whatever radiocarbon dating says) it is of limited utility due to the inherent lack of unprecedentedness.
An interesting example from Scandinvia where ree remain uncovered by a receding glacier shows that forests grew several hundred meters higher than now during the early Holocene:
Recent glacier/ice patch recession in association with post-Little Ice Age climate recovery of the past 100 years or so has exposed a plethora of previously ice-entombed megafossil tree remains in many parts of the world…
Kullman is an acknowledged authority of climate and vegetation history in Scandinavia, but even so he had to publish this paper in an obscure geography journal. And he must be getting very close to retirement so he can afford to speak his mind.
It’s got to be tough on climate-related scientists who don’t toe the line. People like Jan Esper, Anders Moberg, Friederike Wagner-Cremer were shouted down every time they pointed out flaws in the AGW narrative.
The sky is falling, the glaciers are melting, the seas are rising. Please send us grant money so that we can study this in detail and produce the final solution.
Seems to me that the basic problem is the Media. they pick up a projection, ie a wild guess, then printed or talk about it on TV as if it is a fact.
Then our politicians, either stupid , or because they want to scare us , run with it.
Look at a map of South America, there is a line of volcanos running South, they pass under West Antarctica and end up at Mt. Erebus by the South Pole.
So heat warms the water and ice melts.
Even at the worst scenaaro, the sea level rises, so what. The Dutch have faced this situation for hundreds of years and they do not have a problem adopting, so the rest of the world will so adopt.
Hundreds of years ahead is hardly a problem. As usual its all about a Grant of money.
While fossil fuels will dominate the energy mix for much of this century, does anyone really believe that better source of energy won’t be added to the mix between 2100 and 2250?
By 2250? That’s more than 230 years from now. By then, fusion should be just 30 years away, as long as we don’t skimp, and put a couple of quadrillion dollars more research money into it.
… and long before that its luminosity will increase enough to sterilize planet Earth of all life above ground and vaporize the oceans.
u.k.(us)
January 5, 2019 3:58 pm
Terrifying, is when the favorite is closing in on your horse, you’re at 20-1 and the horse is begging for the wire,
the jockey is trying to lose weight and become one with the horse’s momentum….
Tom Abbott
January 5, 2019 3:59 pm
From the article: “If every country meets its current commitment under the Paris Agreement, the Earth will warm about 2.7 degrees Celsius by the end of the century compared with its pre-industrial average.”
Pure speculation. This is what passes for climate science.
The fact is they have no idea if the Earth will warm that much or even at all by the end of the century. Yet they make these declarations as if they are rock-solid.
Alarmist climate science is just one unsubstantiated claim after another. It’s infuriating.
To make it true, they will place the beginning of the industrial age at the coldest point of the Maunder Minimum, and annually adjust that temperature until it is 2.7 degrees colder than 2100. “He who controls the present controls the past; he who controls the pas controls the future.” Is one of the 3 main slogans of the party Ingsoc (Labour/Tories).
Robert Osborn
January 5, 2019 5:25 pm
Cinematic, yep! All they need is a good cast and a good script. Perfect for Al Gore as producer.
EVIDENCE OF STABILITY OF THE WEST ANTARCTIC ICE SHEET
In May, 2015, a New York Times headline stated “Scientists Warn of Rising Oceans from Polar Melt” and goes on to say: “A large section of the mighty West Antarctica ice sheet has begun falling apart and its continued melting now appears to be unstoppable” and “the melting could destabilize neighboring parts of the ice sheet and a rise in sea level of 10 feet or more may be unavoidable in coming centuries.” Virtually every newspaper and TV news show went ballistic with dire predictions of the “unstoppable” catastrophe about to unfold. Two papers on the Pine Island and Thwaites glaciers in West Antarctica triggered this renewed outburst of catastrophic predictions. AWashington Post headline stated “Research casts alarming light on decline of West Antarctic Glaciers” and goes on to say that “a rapidly melting section of the West Antarctic ice sheet appears to be in an irreversible state of decline, with nothing to stop the glaciers in this area from melting into the sea” and “the region’s mile-thick ice sheet could collapse and raise sea levels as much as 11 feet.The consequences of such an amount of sea-level rise for the United Stateseor for any other coastal regiondare staggering to contemplate.12.8 million Americans live on land less than 10 feet above their local high-tide line.$2.4 trillion worth of property is occupying this land, excluding Hawaii and Alaska.The cities that would be most affected include Miami, New Orleans, and New York.Within 100e200 years, one-third of West Antarctica could be gone.The effects of climate change are outpacing scientific predictions, driven in part, scientists say, by soaring levels of greenhouse gases in the atmosphere.” In apaper titled “Widespread,Rapid Grounding Line Retreat ofPine Island, Thwaites, Smith, and Kohlerglaciers, West Antarctica from 1992 to 2011,” Rignot et al. (2014) contend that increased flow velocity of several small outlet glaciers of the West Antarctic Ice Sheet as a result of increased rates of calving into the sea will lead to “unstoppable collapse” of the entire West Antarctic Ice Sheet and raising of sea level by 4 ft, which will displace tens of millions of people from coastal areas around the world. According to Rigot, an electrical engineer, “Warm ocean currents and geographic peculiarities have helped kick offachain reaction at the AmundsenSea-areaglaciers, melting them faster than previously realized and pushing them ‘past the point of no return’.The system [becomes] a chain reaction that is unstoppable, [with] every process of retreat feeding the next one.The glacial retreat there appears unstoppable.” Curiously, Rignot asserts that “heat makes the grounding line retreat inland, leaving a less massive ice shelf above. When ice shelves lose mass, they can’t hold back inland glaciers from flowing toward the sea.” Apparently he believes that the terminal area of the glacier acts like a dam, “holding back” the rest of the glacier, and if it is removed, the glacier will essentially slide into the sea. That’s a false premisedevery glaciologist knows that where a glacier terminates is determined by its mass balance between the amount of accumulation of new ice every year and the amount of ice loss by melting or calving. Thus, an important factor for the Rignot “unstoppable collapse” of the West Antarctic Ice Sheet is based on a false premise. In a paper titled “Marine Ice Sheet Collapse Potentially Underway for the Thwaites Glacier Basin, West Antarctica,” Joughin et al. (2014) also infer that the entire West Antarctic Ice Sheet will soon disappear, resulting in a sea level rise of up to 10 ft. The authors contend that recent retreat of the Pine Island and Thwaites glaciers has occurred because warm ocean water has caused melting of ice on the underside of the glaciers, causing them to thin and calve more rapidly. Because the base of most of the West Antarctic Ice Sheet lies below sea level, the authors contend that ocean water will melt its way up several small embayments under the ice sheet, which is more than 1000 miles across, and cause it to collapse abruptly. They refer to this as “unstoppable” because the glacier base is below sea level and they claim that there is nowhere that the glacier can ground, resulting in total collapse of the ice sheet into the sea. To get a perspective of what is happening now and what might or might not happen in the future requires a look at the overall geologic setting and the scale of the size and thickness of the West Antarctic Ice Sheet relative to the Pine Island and Thwaites outlet glaciers. The West Antarctic Ice Sheet makes up only about 8½ % of Antarctic ice, and the Pine Island glacier makes up about 10% of the West Antarctic Ice Sheet. Most of the West Antarctic Ice Sheet lies SE of the Pine Island glacier and at its SW margin is about 1000 miles from the Pine Island and Thwaites outlet glaciers. Ice in the SE region flows into the Ross Sea, making the Ross Ice Shelf, and has little if anything to do with the part of the ice sheet that flows through the Pine Island and Thwaites outlet glaciers far to the north beyond the ice divide. The Pine Island and Thwaites glaciers are not independent glaciersdthey are ice streams from the NW part of the West Antarctic Ice Sheet flowing through narrow embayments bounded by mountains. Their termini calve into the Amundsen Sea, but the rest of the ice sheet is grounded and all of the southwestern part discharges into the Ross Sea. The entire western and southern margins of the West Antarctic Ice Sheet are separated from the ocean by mountains, so these are virtually the only outlets for the ice. The total width of the Pine Island and Thwaites outlet glaciers makes up only about 60 miles of the 2500 miles of coastline along the western and southern margins of the
IV. POLAR ICE
8. EVIDENCE OF STABILITY OF THE WEST ANTARCTIC ICE SHEET 131
ice sheet. The major ice discharge from the SW margin into the Ross Ice Shelf is not affected by what goes on in the northern part of the ice sheet. Scale is importantdonly when looking a map of the size of the West Antarctic Ice Sheet does it become apparent just how tiny the Pine Island and Thwaites outlet glaciers are relative to the size of the West Antarctic Ice Sheet (Figs. 7.13 and 7.16). The rate of glacial retreat is estimated at 10e23 ft per year. The West Antarctic Ice Sheet is roughly 800e1000 miles across, depending on where you measure it. So melting at 10 ft per year would take 528,000 years and at 23 ft per year would take 229,565 years.
9. CREDIBILITY OF THE “UNSTOPPABLE COLLAPSE OF THE WEST ANTARCTIC ICE SHEET”
The base of most of the West Antarctic Ice Sheet lies below sea level (Figs. 7.17 and 7.18) and it is because of this that the West Antarctic Ice Sheet is predicted to collapse. The deepest parts of the subglacial basin are mostly about 10,000 ft (3300 m) deep and lie beneath the central portion of the ice sheet where the ice is the thickest (Fig. 7.19). More important than just depth below sea level is how thick the ice is relative to the depth below sea level. If the ice is thicker than the depth of its base below sea level, the ice will not float.
9.1 Thickness of the West Antarctic Ice Sheet
Fig. 7.19 shows the thickness of the West Antarctic Ice Sheet. Most of the ice sheet is more than 6000 ft (2000 m) thick and in places, reaches up to 10,000 ft (3000 m) thick. The importance of ice thickness is that virtually all of the ice sheet is considerably thicker than the depth below sea level to bedrock, so the ice is grounded and will not float. Also important is the source area of the outlet glaciers. Fig. 7.20 shows ice divides and ice drainage areas. The Pine Island outlet glacier drains only a relative small portion of the West Antarctic Ice Sheet, so it is difficult to see how events there could result in collapse of the entire Antarctic Ice Sheet.
FIGURE 7.16 Pine Island outlet glacier and the northwestern part of the West Antarctic Ice Sheet.
FIGURE 7.17 Subglacial topography of the West Antarctic Ice Sheet.
IV. POLAR ICE
7. EVIDENCE THAT ANTARCTICA IS COOLING, NOT WARMING132
The authors assert that “we find no major bed obstacle that would prevent the glaciers from further retreat and draw down of the entire basin.” But that is contrary to what is shown in Fig. 7.21, which is a profile of the West Antarctic Ice Sheet from the east coast to the Transantarctic Mountains, showing thickness of the ice sheet, sea level, and the subglacial floor. At its deepest part, the subglacial floor is 2000 m (6500 ft) below sea level, but almost all of the subglacial floor in this profile is less than 1000 m (3300 ft) below sea level. The ice is mostly more than 2500 m (8000 ft) thick, so basic physics tells us it will not float in 1000 m (3300 ft) of water nor will sea water melt its way under the ice. At 200 km (125 miles) up-ice from the terminus, the ice sheet is about 1600 m (5200 ft) thick and the subglacial floor is above sea level. At 300 km from the terminus, the subglacial floor is 1000 m (3300 ft) above sea level. About 700 km from the terminus, the ice is about 1700 m (5500 ft) thick and the subglacial floor is near sea level. About 1050 to 1150 km (650e700 miles) from the terminus, bedrock occurs at sea level. Because the depth of the subglacial floor below sea level is substantially less than the thickness of ice, it will not float and collapse!
Such physical facts do not deter alarmist rhetoric to the uneducated masses. The climate Alarmists depend on stupified Arts majors journalists to spew their propaganda fact-free.
The history of deglaciation of the West Antarctic Ice Sheet (WAIS) gives clues about its future. Southward grounding-line migration was dated past three locations in the Ross Sea Embayment. Results indicate that most recession occurred during the middle to late Holocene in the absence of substantial sea level or climate forcing. Current grounding-line retreat may reflect ongoing ice recession that has been under way since the early Holocene. If so, the WAIS could continue to retreat even in the absence of further external forcing…
H. Conway et al, 1999. Past and Future Grounding-Line Retreat of the West Antarctic Ice Sheet. Science 8 October 1999: Vol. 286 no. 5438 pp. 280-283
The collapse (retreat of the grounding line) began about 20,000 years ago. It is irreversible because “the WAIS could continue to retreat even in the absence of further external forcing” and there are no topographic obstacles to prevent it from flowing downhill into the ocean.
Baiscally, the “collapse” has been ‘irreversible” since the last glacial maximum and will remain “irreversible” until the onset of the next glacial stage.
“Our findings overturn the assumption of progressive retreat of the grounding line during the Holocene in West Antarctica, and corroborate previous suggestions of ice-sheet re-advance”
Yes, I saw that paper. It is quite interesting. It is difficult to explain the presence of detectable quantities of radiocarbon under the WAIS without a readvance of the grounding line.
A I’ve pointed out before it is most unfortunate that the WAIS Divide ice coring project deliberately avoided drilling all the way to bedrock.
“If the ice is thicker than the depth of its base below sea level, the ice will not float.”
Actually “If the ice is thicker than 113% of the the depth of its base below sea level, the ice will not float.” Salt water is appreciably denser than glacier ice.
‘And where are those figures you refer to? Not in Joughin et al. or Rignot et al.
noaaprogrammer
January 5, 2019 7:54 pm
If these climastrologists want to gorge themselves on catastrophes, just go to the Book of Revelation: the sun scorches people with intense heat; the sea turns to blood, hailstones that weigh a hundred pounds, etc., etc.
Johann Wundersamer
January 6, 2019 3:34 am
“MICI, which maintains that West Antarctic glaciers will eventually crumble under their own weight.”
No. Miezi or Miauzi is the pet name for cats.
Kyle in Upstate NY
January 6, 2019 3:37 am
What’s absolutely amazing and astounding is that these idiots actually think they can accurately predict what might happen in hundreds of years, AND how it supposedly would affect humans because apparently they think they can predict a couple of hundred years worth of technological and economic development before it has happened. The next one hundred years alone is going to see far more scientific and technological development than the last one hundred, given how fast such development happens now, and the last one-hundred saw quite a bit. The next one hundred years after that…!?
eternaloptimist
January 6, 2019 5:22 am
For those of you that are truly concerned about your descendants in 300 years,
put 100 bucks into the bank.
if you can get 7% it will be worth $92,089,449,276
“It might not happen,” Fricker said. “But if there’s a chance that it could happen, then shouldn’t you involve that in your planning? If you’re hosting a picnic and it might rain, you don’t necessarily move the whole event, but you probably do make a Plan B.”
Here we go again with the “could”. Note the clever misdirection: “Could”, to a scientist, means that it is not logically impossible. That includes a whole pile of absurdly unlikely events.
But “might”, to a picnic-goer, means some reasonable chance of rain: maybe 10%, maybe 50%, depending on how much you want your picnic dry. It doesn’t mean 0.0001%, which is definitely included in a scientist’s “could”.
Now, the next question to ask is were those coding errors accidental or deliberate.
And the question after that is should we be spending trillions of extra dollars fighting CO2 before we even know the quality of the computer models that claim CO2 is detrimental and huge sums need to be spent to mitigate the problem?
Hocus Locus
January 6, 2019 5:34 pm
How can you plan for something that’s never been observed?
Are we now able to controle the vulcanic thermal output in West Antarctica by reducing CO2 levels ?
Let’s cherry-pick the current history of Akak Karkatau: https://en.wikipedia.org/wiki/Krakatoa#Anak_Krakatau. Sudden change in sea level in a few moments.
There is long time before 2500. Climate models do not predict volcanic events and fate of the plate tectonics.
They can’t seem to do anything without models. Just like real life human models, its pretty on the outside be nothing of value on this inside.
I expect sea levels to drop an inch or so over the next 50 years due to the new Grand Solar Minimum…
Unfortunately, man’s ground water pumping in semi-arid regions will offset much of any ice storage on land by nature.
With the “Great Greening^ тм” and higher CO2, water will be conserved. Also, these aquifers can be recharged. The main problem with much of CAGW ‘science’ is the one way street the alarmists are on. The Sahara aquifers were charged during prevoous wetter greener periods. We may be fighting frigid climate and sea level drop by 2100.
Groundwater becomes salty over geologic periods of time, so none of the freshwater aquifers are truly ancient waters.
This 2004 paper by Sturchio et al in Geophysical Research Letters may suggest otherwise…
I don’t know whether it has been challenged, but it seems clear that million year old Nubian groundwater is “freshwater” rather than saline. No idea whether it is potable, as the paper is silent.
One million year old groundwater in the Sahara revealed by krypton‐81 and chlorine‐36
https://doi.org/10.1029/2003GL019234
Wake me up when Antarctica gets above zero anymuch.
Pure (insert preferred profanity) alarmism. Like shouting Fire! In a crowded theatre.
Fortunately, their theatre is pretty empty these days.
I wonder if it is not time to get a “sciency paper” submitted to these foolish publishers.
I propose that as the continental plates slide under one another,that ground water will flood to the surface drowning all…for “recent studies” show there is far more water in the mantle than we previously suspected.
And everybody knows that dirt displaces water…
Therefore ;”We are all going to die” TM ( Some conditions apply, normal life expectancy excetera).
I confess to being bored with the constant bloviating of “Unspecified Doom” that passes for modern science.
So to spice things up a bit perhaps some creative myth making is in order.
Maybe we could have a big show every year and pass out Global Warming Edutainment awards?
This Spring, the first annual gala presentation of the Golden W.E.D.G.I.E Awards!
Wedgies give for gold is a slim eating plan.
ask
https://www.google.com/search?client=ms-android-samsung&ei=kOExXPjEEouNrwT3zZ_oDw&q=king+turned+everything+to+gold&oq=everything+to+gold+king&gs_l=mobile-gws-wiz-serp.
Thank you again David for a great explanation.
For the uninitiated twit on WUWT (me) It never occurred to me that calving of glaciers was more likely due to excess ice thanks to increased snowfall at the centre of the continent pressing down and expanding the ice sheet rather than warm sea’s melting the ice.
Mind you, I don’t believe for a moment 1.5C warming of the atmosphere, or land for that matter, could affect sea temperatures by any more than a minuscule fraction of a degree, if that.
My understanding is that the volume and density of water far outweighs any warming effect the thin, weedy atmosphere could have on SST’s never mind deep ocean temperatures.
I think I might be getting the hang of this AGW nonsense.
Hot Scott,
The DMI Greenland mass budget page is educational. You may want to check it out if you haven’t already.
https://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/#
This is not terrifying. Wars are terrifying. If sea levels rise then people will relocate.
“If sea levels rise then people will relocate.”
LMAO. Nope we won’t. Even if they rise by say 1 meter we will stay put (we=NL).
We already have dikes and spring tide storm flood protection which was designed to take on much, much, much higher levels of water from the North Sea. As in more than 10 meters (30 feet).
That may seem slightly ridiculous as the highest (known & recent) wave in the North Atlantic was 19 meters (https://www.theguardian.com/world/2016/dec/13/highest-ever-wave-sets-record-iceland-britain-north-atlantic) yet in the North Sea itself with such heights are very unlikely because the sea bottom is rather shallow in many places.
Yet on 1st of January 1995 when waves of 12 meters were measured (near NL and UK) one freak wave occurred of 25.6 meter high (with a peak above water level of 18.5 m) ( https://en.wikipedia.org/wiki/Draupner_wave).
What world do these clowns live in that they can get away with publishing fiction as actual scientific research?
classically defined “Groupthink” is underlying cause of mainstream junk climate science.
science.edu
…. don’t forget science.gov
both paid for with tax dollars to rentseekers.
Science.edu/tainment
Either they’re taking the MICI or they’re headed up a blind Alley!
They better switch to The Rocky Horror Show instead of watching Waterworld in a loop while typing their papers.
But the Rocky Horror Picture Show was the genesis for the support for transvestite, transsexual undocumented aliens. I’d suggest “Ice Age” (2002).
DeConto and Pollard was the direct cause for the Dutch alarmistic sealevel report by Deltares.
https://www.deltares.nl/app/uploads/2017/04/Hackathon-resultaten-rapport.pdf
Oh no, it’s the “something might happen in the future and if we don’t prepare for it now we’re all doomed” mantra again. Don’t forget your great, great, great, children and while you’re at it send money to perpetuate research into the not so imminent, but catastrophic, results of your inaction.
Don’t expect the propaganda to end anytime soon:
“GRIM FORECAST A senior environmental official at the United Nations, Noel Brown, says entire nations could be wiped off the face of the earth by rising sea levels if global warming is not reversed by the year 2000.
San Jose Mercury News (CA) June 30, 1989 – 3F General News”
I gotta find a copy of that newspaper and frame it… LOL!
https://www.apnews.com/bd45c372caf118ec99964ea547880cd0
“Dr. Brown currently serves as President of the Friends of the United Nations”… Any friend of the United Nations is an enemy of individual liberty and prosperity!
https://www.rootsofpeace.org/team/dr-noel-brown/
+42
Notice that those maps of Jakobshavns Isbrae ends in 2007, ten years ago. Why?
The reason can be seen here:
https://worldview.earthdata.nasa.gov/?p=geographic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines&t=2018-09-21-T00%3A00%3A00Z&z=3&v=-50.760841981818906,68.8345362149479,-49.260109559943906,69.5563379727604
This is a satellite image taken 21 sept. 2018. Ignore the black “coast-line, it is obsolete. The current ice cliff is visible as the border between the white calved ice and the slightly darker glacier ice (it is darker because at this date someb melting is still going on).
Notice that it has hardly changed at all since 2007 when it reached the coast. It is still just a little “upstream” from the ice free cliffs north and south of the glacier. That is why maps of ice recession never get past 2007.
tty
The link is not useable. It runs off the right edge of the page.
Unfortunately WordPress does not support long links. The link is actually there but almost invisible.
What you do is copy and paste. Start att https.. and drag to …27604 and paste into browser. At least it works for me with Chrome
tty,
It still isn’t working. It takes me to EOSDIS World View (as does the first two lines), but the screen is black. Perhaps something got cut out at the edge.
As I say it works for me. But here is the complete link in sections, hope this will display correctly:
https://worldview.earthdata.nasa.gov/?p=geographic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),
MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),
Reference_Features(hidden),Coastlines&t=2018-09-21-T00%3A00%3A00Z&z=3&v=-50.760841981818906,68.8345362149479,-49.260109559943906,69.5563379727604
All I get is a blank screen too.
The link is broken, WP creates a break, and when trying to Copy Paste, leaves that break.
So, fixed that.
Here y’all go.
https://tinyurl.com/yb4wsbbw
tty – a useful place that turns long urls into short ones is https://tinyurl.com/
Ha! Should have kept reading, I’m only 8 days behind.
Test
Link
tty
Forgive me for exhibiting my ignorance but clarification would be appreciated.
According to the observations in this article, I understand that calving intruded into the glacier up to the lines marked as 2005/2006. Is that correct? In other words the estuary (for want of a better expression) was essentially ice free up to that point, perhaps in the summer? (I realise it may have been still packed with ice but it was free floating icebergs rather than connected glacial ice).
From the 2018 satellite observation you post, glacial calving now intrudes into the estuary only as far as calving in 2001 or so?
So in other words, the glacier has been growing for the last 12 to 13 years?
And whilst a crude description, is that close to the observations?
No, the estuary is and has alway always been full of calved ice (dead white in the satellite image). Jakobshavns isbrae drains more than 100 000 km^2 of the icecap so calving is always intense.
And no it hasn’t been growing for the last 12 to 13 years. It has been essentially stationary until 2017-2018 when it did grow slightly:
http://polarportal.dk/fileadmin/user_upload/polarportal-saesonrapport-2018-EN.pdf
The fjord wasn’t ice-free… And still really isn’t ice-free. In 1851, the floating ice tongue extended all the way down to the 1851 calving line…
The Landsat photo is from 2001. Note the change at the 2001 calving line. The gray to the right of the calving line was a floating ice tongue. You can see some lineations parallel to the fjord. These are flow lines. Downstream of the 2001 calving line, the fjord is a mottled white color due to lots of floating chunks of ice. In 1851, the ice would have been gray with flow lines all the way down to the 1851 calving line. The calving lines subsequent to 2001 are superimposed on the floating ice tongue. A Landsat photo from 2006 shows that the gray area had moved about as far upstream as it could move…
Jakobshavn’s “iceberg” factory moved from the bottom to the top of the fjord from 1851-2006. Its rate of iceberg production will likely decline unless the ice mass in its drainage area increases faster than it is ablating.
” Its rate of iceberg production will likely decline unless the ice mass in its drainage area increases faster than it is ablating.”
Paradoxically the amount of ice “upstream” may actually increase once the glacier front is on land and no longer calving. It is well documented that glaciers that are melting rather than calving are significantly steeper than calving glaciers. This was noticeable in the NEEM ice-core where the enclosed air bubble suggest that the ice was about as thick or even slightly thicker than now at the center during the Eemian interglacial when the Greenland icecap was significantly smaller and probably mostly did not reach the coast.
Even NASA cutsoff Jakobshavn Glacier pictures to 2010.
You can see the slowdown, which is probably reversing now for the last 8 years, an inconvenient fact they are hiding, else they would show it.
Go to Bing Maps and navigate to the site.
Click on aerial view.
Gives a pic from 2018, ice is back to where it was in around 1964 in the center of the fjord.
And the pic is from mid summer…no ice in the water, melt pools on the surface of the glacier visible.
69.172705, -49.965326
https://www.bing.com/search?q=bing+maps+jaakobshovn+greenland&form=EDGEAR&qs=PF&cvid=75c5b174c3db4bedb61474679364211b&cc=US&setlang=en-US&elv=AY3%21uAY7tbNNZGZ2yiGNjfPJehQQaBhwd7LieV%21FlCavj8PproAoCpGCiUCA5T9nBHsCMZvdBzdVws8VOhOwO2vm1u3XwyWPjr%21hfUH4fEYL&PC=HCTS
Hmmm…it may be that the views are doctored or masked.
Expanding out shows all of Greenland surrounded by water and the glaciers all have razor sharp cut off lines.
They are definitely masked. Ilulissat fjord is always chock-full of ice in summer. 10% of all Greenland icebergs come from it. Better use EOSDIS Worldview.
David and tty,
Has anyone offered up a coherent explanation for the tongue receding as it did prior to 2001?
More in particular the retreat in the 100 years between 1851 and 1953, when according to the IPCC’s mantra, anthropogenic CO2 did not have the impact it insists it has had since the 1950s?
Seems like a reasonable question to me.
Little Ice Age ended about 1850 and glaciers started receding all over the Northern Hemisphere.
What tty said, plus Neoglaciation ended around 1850. From the Holocene Climatic Optimum (~4-7 ka) glaciers were generally intermitenrly advancing. This interval is known as Neoglaciation.
The coldest part of the Little Ice Age (~1600-1700) was probably the coldest phase of the Holocene.
David,
The Jacobshavn/Illulisat Isbree break-up point may have been advancing between 1965 and 2000, due to colder weather over Greenland. I have the Greenland temperatures up to 2005 here:
http://www.ferdinand-engelbeen.be/klimaat/greenland_temp.html
Where the periode 1930-1950 was near as warm as after 2000.
BTW, the icebergs are about 800 m high and are blocked by a underwater morene at the end of the Illulisat fjord. Pushed by the advancing of the glacier behind it and tides, they occasionally float into the oceans. Incredible view from out of the air from our 2000 trip to Greenland ( http://www.ferdinand-engelbeen.be/familie/greenland.html ):
http://www.ferdinand-engelbeen.be/familie/groenland/grl022.jpg
Good find, Ferdinand! +42×1042
Ferdinand, your photo tour makes me want to go there.
To me, the Bing maps seem to suffer the application of an algorithm that makes all the seawater the same color.
Look at Google Maps for 2019 pictures that show all the ice in the estuary. Note how the west end of the glacier seems to be calving into two streams of ice, one NE and one SE. That is much farther upstream than anyone has talked about.
https://www.google.com/maps/place/Ilulissat,+Greenland/@69.1772466,-50.3999507,73465m/data=!3m1!1e3!4m5!3m4!1s0x4ef2ac312385d59d:0xe228279619f90f6a!8m2!3d69.2198118!4d-51.0986031?hl=en
John, as we like to travel to mountain ranges and cold regions, this indeed was one of the nicest experiences we had. The landscape can be compared to fjord regions all over the world, especially Norway (our favorite for over 10 times), but over an enormous area, even with much less inhabitants. No roads between “towns”, the longest road is between the capital and the airfield: about 7 km, with only one traffic light in the town and all of Greenland… Still they had Internet and smartphone connections in every distant village and music making and recording was – in 2000 – their favorite hobby. Quite expensive country as they have to import near everything with only one export product: fish (mainly halibut to Europe and deep sea shrimp to Japan). Denmark still provides 1/3 of their yearly budget, although they have practical independence. As far as I have seen on TV, there is coming some mining exploration in the mountains, thanks to the retreat of several glaciers.
Daughter Ann made a different tour with more heavy walks (like up to the inland ice) over the same period and did do dog sledging on Disko Island in the same region (Disko bugt/bay) as Ilulussat, all middle summer.
The Ilulissat Isfjord is an incredible view with a lot of noise from colliding icebergs. The speed the glacier/icebergs are traveling is one of the fastest in the world: average around 7 m per day. Camping is forbidden near the coast as icebergs may turn around when the downside melts away and may give a flood of several meters high.
The “feed” to the glacier indeed is much farther inland that the breaking point where the glacier breaks up in (large) pieces. The Landsat shows only the breaking point…
This all sounds like more alarmism based on “If anything EVER changes it’s bad and caused by humans”.
Is ‘scariest’ a scientific expression?
Gamecock
It is the scariest scientific expression! 🙂
Is that before or after “unprecedented”??
Incidentally “Ice Cliff Collapse” does occur. It happens when a glacier resting on sea-bottom reaches a water depth of about 500 meters. The 10% of the glacier that emerges above the surface then becomes mechanically unstable.
This is the basic reason the Antarctic ice doesn’t change very much between glacials and interglacials. It is basically as large as it can be. It is only when Northern Hemisphere glaciation lowers sea-level that it can extend a little further down the continental slopes.
Well, sometimes it does grow during interglacials too, because more snow falls, but then the central parts become thicker without much change along the periphery
I’m confused about this. It would seem to me that as the water gets deeper, at some point the glacier would start floating. Also, I thought it was above 100 m height that an ice cliff becomes unstable.
It depends on the thickness of the glacier if it is too thick to float it will extend seawards on the bottom until it becomes unstable. If it is relatively thin it will “float off” and form a shelf-ice or a glacier tongue. However this mostly applies to Antarctica. In the Arctic it is rarely cold enough for shelf ice or long glacier tongues to be stable (except occasionally in fiords). Even in the Antarctic shelf ice usually needs islands as “anchoring points” for stability.
The 500 meter figure is based on the maximum depth that icecaps have reached in the past based on studies of bottom morphology. I have occasionally seen “ice cliffs” higher than 50 meters, but they have all either been on land or in very shallow water.
Let me see.
1 – Ice is frozen water.
2 – Glaciers are ice.
3 – If glaciers were liquid, they’d be water.
4 – Gravity pulls on things, and they move down.
5 – Gravity pulls on glaciers, making them move toward a lower level.
6 – Gravity pulls on water making it flow toward a lower level.
7 – Gravity, ice and water are part of the natural world.
8 – The natural world is full of changes.
9 – Changes scare science peeps.
10 – Science peeps want money.
11 – Science peeps write scary stories about changes to get money.
Does anyone besides me see a scam going on here?
When these people make a projection that is anywhere from 50 to 250 years out, and most of them will NOT be around to see anything they predict, do they really believe they can sell this scam to anyone except those who are easily-panicked over everything?
Is there any way at all to stop this scam? This is becoming more and more ridiculous. By 2325, we may be living south of the Mason Dixon line with ice sheets 1.25 miles thick slowly moving southward. The Fertile Crescent may be green again. When the meteorology people can’t make an accurate forecast more than two days out, do these scammers really expect to be taken seriously?
Anyone who gives them money – PLEASE STOP NOW!!!!
Sara
“Is there any way at all to stop this scam?
Sadly, I think we all share your frustration.
Anyone who gives them money – PLEASE STOP NOW!!!!
As much as I would like to stop paying taxes it seems I can’t. Our incomes and bank accounts are remotely and automatically monitored by our respective taxation organisations (HMRC in the UK) and if my National Insurance number doesn’t equate to an income from a legitimate source then they will be down on me like a ton of bricks.
Our governments love the concept of cash free transactions, they despise physical money because they can’t track every penny you make and spend. They can, however, do so with ecommerce.
And whilst the ‘alternative’ economy makes up a fraction of most civilised countries economy, our governments will spend vast fortunes, far outweighing what they are combating, to ensure everyone is compliant.
HotScot, I am just about ready to go live in a yurt!
I’m in what you call ”pensioner” status – retired. My income may be modest, but I own my teensy-weensy home and the tax on it is also modest. My utilities charges are also modest. What I have is affordable on my income, and leaves a little room for fun.
What these creatures want to do is destroy that for no reason other than their own confounded greed.
Any time someone asks for a grant or largess from the government, out of tax money that should go for real-world things like repairing roads and bridges and emergency response teams and better weather forecasting – normal things that we need – but instead goes for a baloney program that is built on scare tactics, it is far past time to shut that nonsense down.
Everything I am seeing about so-called climate change “science” appears to be a scam, a fraud foisted on taxpayers for no real purpose beyond lining the pockets of people who contribute nothing of any use. If any of that nonsense improved weather forecasting, I would be less harsh, but it does not. When I look back at my own records and compare them with what Accuweather forecasts, the result is that Accuweather is consistently inaccurate for any forecasting beyond 2 to 3 days out.
Like I said, I’m about ready to move into a yurt.
“Fricker said. ‘But if there’s a chance that it could happen, then shouldn’t you involve that in your planning? If you’re hosting a picnic and it might rain, you don’t necessarily move the whole event, but you probably do make a Plan B.”
What Fricker and others of his ilk don’t seem to realize is, that possibilities are not the same as probabilities. If the weather forecast is only 5% probability rain, one makes different picnic plans than if the probability is 95%! It is all these interminable “could, might, possibly, conceivable” that are inherently low probability but of unquantified probability that the alarmists milk. Hell, I MIGHT die tomorrow. That is a true statement. However, it doesn’t change the way I behave just because of the word “might.”
David
Thank you for providing that extra information about Jakobshavn. I had read some background on it but frankly forgot what it was. But, as usual I believed it was reassuring and the hype not reconciling with the facts.
Each time I read about some of these apocalyptic papers and conferences, my first reaction is to ask the question “Aren’t there any adults in the room.”
Really, what happened to the old, calming hands who say let’s take our time and think this through. I guess they’ve been bullied into retirement.
And to pick up on a comment above, there are papers which address the issue of geothermal activity affecting Pine Island and Thwaites. If they want to have a more complete understanding of the dynamics that are at play they should spend more time on that kind of research. But would music majors be interested? Probably not.
There were “adults in the room”…
https://www.theatlantic.com/science/archive/2019/01/sea-level-rise-may-not-become-catastrophic-until-after-2100/579478/
So most of the melting happened before our (in)significant contribution to the world’s CO2. Doesn’t that disprove their entire hypothesis?
yes
It doesn’t disprove it… But it renders it much less significant.
I like it when glaciers recede and somebody goes up there and finds the remains of some 500 year old tree at the new base of the glacier. It’s happened before. Kinda like people digging through perma-frost to see how the Vikings lived in Greenland when there wasn’t perma-frost to dig through.
Kinda puts the word “unprecedented” into proper context.
That is why trees etc revealed by receding glaciers are so seldom mentioned by the climatariat. While incontrovertible proof that the glacier hasn’t been this small for X years (whatever radiocarbon dating says) it is of limited utility due to the inherent lack of unprecedentedness.
An interesting example from Scandinvia where ree remain uncovered by a receding glacier shows that forests grew several hundred meters higher than now during the early Holocene:
https://www.researchgate.net/publication/324991910_Further_Details_on_Holocene_Treeline_GlacierIce_Patch_and_Climate_History_in_Swedish_Lapland
I love the way this paper starts out…
(7) (PDF) Further Details on Holocene Treeline, Glacier/Ice Patch and Climate History in Swedish Lapland. Available from: https://www.researchgate.net/publication/324991910_Further_Details_on_Holocene_Treeline_GlacierIce_Patch_and_Climate_History_in_Swedish_Lapland [accessed Jan 05 2019].
I’m surprised this phrase passed peer-review… “post-Little Ice Age climate recovery of the past 100 years or so”… LOL!
Kullman is an acknowledged authority of climate and vegetation history in Scandinavia, but even so he had to publish this paper in an obscure geography journal. And he must be getting very close to retirement so he can afford to speak his mind.
It’s got to be tough on climate-related scientists who don’t toe the line. People like Jan Esper, Anders Moberg, Friederike Wagner-Cremer were shouted down every time they pointed out flaws in the AGW narrative.
Little Ice Age?
You speak strangely.
What is this age you speak of?
Surely no such time exists.
I like your link. I like all the references at the end also.
The sky is falling, the glaciers are melting, the seas are rising. Please send us grant money so that we can study this in detail and produce the final solution.
Seems to me that the basic problem is the Media. they pick up a projection, ie a wild guess, then printed or talk about it on TV as if it is a fact.
Then our politicians, either stupid , or because they want to scare us , run with it.
Look at a map of South America, there is a line of volcanos running South, they pass under West Antarctica and end up at Mt. Erebus by the South Pole.
So heat warms the water and ice melts.
Even at the worst scenaaro, the sea level rises, so what. The Dutch have faced this situation for hundreds of years and they do not have a problem adopting, so the rest of the world will so adopt.
Hundreds of years ahead is hardly a problem. As usual its all about a Grant of money.
MJE
I keep thinking of the Twilight Zone episode, “The Old Man in the Cave”.
https://www.youtube.com/watch?v=7uAP6HaHXnc
By 2250? That’s more than 230 years from now. By then, fusion should be just 30 years away, as long as we don’t skimp, and put a couple of quadrillion dollars more research money into it.
In 10B years the sun will burn out. Its just something to keep in the back of your mind.
Before it does that, it will envelope the Earth.
… and long before that its luminosity will increase enough to sterilize planet Earth of all life above ground and vaporize the oceans.
Terrifying, is when the favorite is closing in on your horse, you’re at 20-1 and the horse is begging for the wire,
the jockey is trying to lose weight and become one with the horse’s momentum….
From the article: “If every country meets its current commitment under the Paris Agreement, the Earth will warm about 2.7 degrees Celsius by the end of the century compared with its pre-industrial average.”
Pure speculation. This is what passes for climate science.
The fact is they have no idea if the Earth will warm that much or even at all by the end of the century. Yet they make these declarations as if they are rock-solid.
Alarmist climate science is just one unsubstantiated claim after another. It’s infuriating.
Their use of a decimal point shows they have a sense of humor.
Only when they are predicting doom.
When doom fails to materialize, they are most dour, and thoroughly unamused.
To make it true, they will place the beginning of the industrial age at the coldest point of the Maunder Minimum, and annually adjust that temperature until it is 2.7 degrees colder than 2100. “He who controls the present controls the past; he who controls the pas controls the future.” Is one of the 3 main slogans of the party Ingsoc (Labour/Tories).
Cinematic, yep! All they need is a good cast and a good script. Perfect for Al Gore as producer.
Wait a second, we were already told years ago that the WAIS is collapsing and there is nothing that can stop it.
EVIDENCE OF STABILITY OF THE WEST ANTARCTIC ICE SHEET
In May, 2015, a New York Times headline stated “Scientists Warn of Rising Oceans from Polar Melt” and goes on to say: “A large section of the mighty West Antarctica ice sheet has begun falling apart and its continued melting now appears to be unstoppable” and “the melting could destabilize neighboring parts of the ice sheet and a rise in sea level of 10 feet or more may be unavoidable in coming centuries.” Virtually every newspaper and TV news show went ballistic with dire predictions of the “unstoppable” catastrophe about to unfold. Two papers on the Pine Island and Thwaites glaciers in West Antarctica triggered this renewed outburst of catastrophic predictions. AWashington Post headline stated “Research casts alarming light on decline of West Antarctic Glaciers” and goes on to say that “a rapidly melting section of the West Antarctic ice sheet appears to be in an irreversible state of decline, with nothing to stop the glaciers in this area from melting into the sea” and “the region’s mile-thick ice sheet could collapse and raise sea levels as much as 11 feet.The consequences of such an amount of sea-level rise for the United Stateseor for any other coastal regiondare staggering to contemplate.12.8 million Americans live on land less than 10 feet above their local high-tide line.$2.4 trillion worth of property is occupying this land, excluding Hawaii and Alaska.The cities that would be most affected include Miami, New Orleans, and New York.Within 100e200 years, one-third of West Antarctica could be gone.The effects of climate change are outpacing scientific predictions, driven in part, scientists say, by soaring levels of greenhouse gases in the atmosphere.” In apaper titled “Widespread,Rapid Grounding Line Retreat ofPine Island, Thwaites, Smith, and Kohlerglaciers, West Antarctica from 1992 to 2011,” Rignot et al. (2014) contend that increased flow velocity of several small outlet glaciers of the West Antarctic Ice Sheet as a result of increased rates of calving into the sea will lead to “unstoppable collapse” of the entire West Antarctic Ice Sheet and raising of sea level by 4 ft, which will displace tens of millions of people from coastal areas around the world. According to Rigot, an electrical engineer, “Warm ocean currents and geographic peculiarities have helped kick offachain reaction at the AmundsenSea-areaglaciers, melting them faster than previously realized and pushing them ‘past the point of no return’.The system [becomes] a chain reaction that is unstoppable, [with] every process of retreat feeding the next one.The glacial retreat there appears unstoppable.” Curiously, Rignot asserts that “heat makes the grounding line retreat inland, leaving a less massive ice shelf above. When ice shelves lose mass, they can’t hold back inland glaciers from flowing toward the sea.” Apparently he believes that the terminal area of the glacier acts like a dam, “holding back” the rest of the glacier, and if it is removed, the glacier will essentially slide into the sea. That’s a false premisedevery glaciologist knows that where a glacier terminates is determined by its mass balance between the amount of accumulation of new ice every year and the amount of ice loss by melting or calving. Thus, an important factor for the Rignot “unstoppable collapse” of the West Antarctic Ice Sheet is based on a false premise. In a paper titled “Marine Ice Sheet Collapse Potentially Underway for the Thwaites Glacier Basin, West Antarctica,” Joughin et al. (2014) also infer that the entire West Antarctic Ice Sheet will soon disappear, resulting in a sea level rise of up to 10 ft. The authors contend that recent retreat of the Pine Island and Thwaites glaciers has occurred because warm ocean water has caused melting of ice on the underside of the glaciers, causing them to thin and calve more rapidly. Because the base of most of the West Antarctic Ice Sheet lies below sea level, the authors contend that ocean water will melt its way up several small embayments under the ice sheet, which is more than 1000 miles across, and cause it to collapse abruptly. They refer to this as “unstoppable” because the glacier base is below sea level and they claim that there is nowhere that the glacier can ground, resulting in total collapse of the ice sheet into the sea. To get a perspective of what is happening now and what might or might not happen in the future requires a look at the overall geologic setting and the scale of the size and thickness of the West Antarctic Ice Sheet relative to the Pine Island and Thwaites outlet glaciers. The West Antarctic Ice Sheet makes up only about 8½ % of Antarctic ice, and the Pine Island glacier makes up about 10% of the West Antarctic Ice Sheet. Most of the West Antarctic Ice Sheet lies SE of the Pine Island glacier and at its SW margin is about 1000 miles from the Pine Island and Thwaites outlet glaciers. Ice in the SE region flows into the Ross Sea, making the Ross Ice Shelf, and has little if anything to do with the part of the ice sheet that flows through the Pine Island and Thwaites outlet glaciers far to the north beyond the ice divide. The Pine Island and Thwaites glaciers are not independent glaciersdthey are ice streams from the NW part of the West Antarctic Ice Sheet flowing through narrow embayments bounded by mountains. Their termini calve into the Amundsen Sea, but the rest of the ice sheet is grounded and all of the southwestern part discharges into the Ross Sea. The entire western and southern margins of the West Antarctic Ice Sheet are separated from the ocean by mountains, so these are virtually the only outlets for the ice. The total width of the Pine Island and Thwaites outlet glaciers makes up only about 60 miles of the 2500 miles of coastline along the western and southern margins of the
IV. POLAR ICE
8. EVIDENCE OF STABILITY OF THE WEST ANTARCTIC ICE SHEET 131
ice sheet. The major ice discharge from the SW margin into the Ross Ice Shelf is not affected by what goes on in the northern part of the ice sheet. Scale is importantdonly when looking a map of the size of the West Antarctic Ice Sheet does it become apparent just how tiny the Pine Island and Thwaites outlet glaciers are relative to the size of the West Antarctic Ice Sheet (Figs. 7.13 and 7.16). The rate of glacial retreat is estimated at 10e23 ft per year. The West Antarctic Ice Sheet is roughly 800e1000 miles across, depending on where you measure it. So melting at 10 ft per year would take 528,000 years and at 23 ft per year would take 229,565 years.
9. CREDIBILITY OF THE “UNSTOPPABLE COLLAPSE OF THE WEST ANTARCTIC ICE SHEET”
The base of most of the West Antarctic Ice Sheet lies below sea level (Figs. 7.17 and 7.18) and it is because of this that the West Antarctic Ice Sheet is predicted to collapse. The deepest parts of the subglacial basin are mostly about 10,000 ft (3300 m) deep and lie beneath the central portion of the ice sheet where the ice is the thickest (Fig. 7.19). More important than just depth below sea level is how thick the ice is relative to the depth below sea level. If the ice is thicker than the depth of its base below sea level, the ice will not float.
9.1 Thickness of the West Antarctic Ice Sheet
Fig. 7.19 shows the thickness of the West Antarctic Ice Sheet. Most of the ice sheet is more than 6000 ft (2000 m) thick and in places, reaches up to 10,000 ft (3000 m) thick. The importance of ice thickness is that virtually all of the ice sheet is considerably thicker than the depth below sea level to bedrock, so the ice is grounded and will not float. Also important is the source area of the outlet glaciers. Fig. 7.20 shows ice divides and ice drainage areas. The Pine Island outlet glacier drains only a relative small portion of the West Antarctic Ice Sheet, so it is difficult to see how events there could result in collapse of the entire Antarctic Ice Sheet.
FIGURE 7.16 Pine Island outlet glacier and the northwestern part of the West Antarctic Ice Sheet.
FIGURE 7.17 Subglacial topography of the West Antarctic Ice Sheet.
IV. POLAR ICE
7. EVIDENCE THAT ANTARCTICA IS COOLING, NOT WARMING132
The authors assert that “we find no major bed obstacle that would prevent the glaciers from further retreat and draw down of the entire basin.” But that is contrary to what is shown in Fig. 7.21, which is a profile of the West Antarctic Ice Sheet from the east coast to the Transantarctic Mountains, showing thickness of the ice sheet, sea level, and the subglacial floor. At its deepest part, the subglacial floor is 2000 m (6500 ft) below sea level, but almost all of the subglacial floor in this profile is less than 1000 m (3300 ft) below sea level. The ice is mostly more than 2500 m (8000 ft) thick, so basic physics tells us it will not float in 1000 m (3300 ft) of water nor will sea water melt its way under the ice. At 200 km (125 miles) up-ice from the terminus, the ice sheet is about 1600 m (5200 ft) thick and the subglacial floor is above sea level. At 300 km from the terminus, the subglacial floor is 1000 m (3300 ft) above sea level. About 700 km from the terminus, the ice is about 1700 m (5500 ft) thick and the subglacial floor is near sea level. About 1050 to 1150 km (650e700 miles) from the terminus, bedrock occurs at sea level. Because the depth of the subglacial floor below sea level is substantially less than the thickness of ice, it will not float and collapse!
Such physical facts do not deter alarmist rhetoric to the uneducated masses. The climate Alarmists depend on stupified Arts majors journalists to spew their propaganda fact-free.
Here’s a good one…
H. Conway et al, 1999. Past and Future Grounding-Line Retreat of the West Antarctic Ice Sheet. Science 8 October 1999: Vol. 286 no. 5438 pp. 280-283
The collapse (retreat of the grounding line) began about 20,000 years ago. It is irreversible because “the WAIS could continue to retreat even in the absence of further external forcing” and there are no topographic obstacles to prevent it from flowing downhill into the ocean.
Baiscally, the “collapse” has been ‘irreversible” since the last glacial maximum and will remain “irreversible” until the onset of the next glacial stage.
Another one.
“Our findings overturn the assumption of progressive retreat of the grounding line during the Holocene in West Antarctica, and corroborate previous suggestions of ice-sheet re-advance”
https://www.ncbi.nlm.nih.gov/pubmed/29899456
Cherry picked, to continue the fun.
Yes, I saw that paper. It is quite interesting. It is difficult to explain the presence of detectable quantities of radiocarbon under the WAIS without a readvance of the grounding line.
A I’ve pointed out before it is most unfortunate that the WAIS Divide ice coring project deliberately avoided drilling all the way to bedrock.
They also wound up with much lower resolution ice cores than they expected.
“If the ice is thicker than the depth of its base below sea level, the ice will not float.”
Actually “If the ice is thicker than 113% of the the depth of its base below sea level, the ice will not float.” Salt water is appreciably denser than glacier ice.
‘And where are those figures you refer to? Not in Joughin et al. or Rignot et al.
If these climastrologists want to gorge themselves on catastrophes, just go to the Book of Revelation: the sun scorches people with intense heat; the sea turns to blood, hailstones that weigh a hundred pounds, etc., etc.
“MICI, which maintains that West Antarctic glaciers will eventually crumble under their own weight.”
No. Miezi or Miauzi is the pet name for cats.
What’s absolutely amazing and astounding is that these idiots actually think they can accurately predict what might happen in hundreds of years, AND how it supposedly would affect humans because apparently they think they can predict a couple of hundred years worth of technological and economic development before it has happened. The next one hundred years alone is going to see far more scientific and technological development than the last one hundred, given how fast such development happens now, and the last one-hundred saw quite a bit. The next one hundred years after that…!?
For those of you that are truly concerned about your descendants in 300 years,
put 100 bucks into the bank.
if you can get 7% it will be worth $92,089,449,276
“It might not happen,” Fricker said. “But if there’s a chance that it could happen, then shouldn’t you involve that in your planning? If you’re hosting a picnic and it might rain, you don’t necessarily move the whole event, but you probably do make a Plan B.”
Here we go again with the “could”. Note the clever misdirection: “Could”, to a scientist, means that it is not logically impossible. That includes a whole pile of absurdly unlikely events.
But “might”, to a picnic-goer, means some reasonable chance of rain: maybe 10%, maybe 50%, depending on how much you want your picnic dry. It doesn’t mean 0.0001%, which is definitely included in a scientist’s “could”.
Take a look at this:
https://principia-scientific.org/nasa-whistleblower-exposes-huge-climate-model-gaffes/
and you’ll see why the “models” are a joke. This one is the first to admit it:
“We will not have analogues … We are going to move outside the instrumental data that we use to calibrate our models.”
Thanks for the link, Yooper.
Now, the next question to ask is were those coding errors accidental or deliberate.
And the question after that is should we be spending trillions of extra dollars fighting CO2 before we even know the quality of the computer models that claim CO2 is detrimental and huge sums need to be spent to mitigate the problem?
https://slate.com/business/2019/01/chicagos-deep-tunnel-is-it-the-solution-to-urban-flooding-or-a-cautionary-tale.html
[…] Harvey was a once-in-10,000-year storm […]
MICI…marine ice cliff instability ?
All cliffs are unstable whether constructed from marine ice or otherwise.
It’s the nature of cliffs