Florida-Sized 'Doomsday Glacier' in Antarctica May Slip Into the Ocean More Quickly
Florida-Sized 'Doomsday Glacier' In Antarctica May Slip Into The Ocean More Quickly:
When measured across geological timescales that span eons, it's fair to say the massive Thwaites Glacier in West Antarctica is in the midst of a collapse. Now new data drawn from the seafloor suggests that it could retreat even faster than previously thought, leading to dramatic impacts on global sea levels.
If the entirety of the Florida-sized ice sheet and some surrounding ice were to slide into the ocean, it could raise sea levels by three to ten feet spelling potential devastation for a number of coastal communities worldwide.
For context, we've seen less than a foot of sea level rise over the past three decades, and that's been enough to increase flooding in a number of places. The worst case scenario were we to lose the Thwaites would redraw coastline maps around the world.
'Doomsday Glacier' is Teetering Even Closer to Disaster Than Scientists Thought
Researchers say the icy mass is "holding on by its fingernails":
Underwater robots that peered under Antarctica's Thwaites Glacier, nicknamed the "Doomsday Glacier," saw that its doom may come sooner than expected with an extreme spike in ice loss. A detailed map of the seafloor surrounding the icy behemoth has revealed that the glacier underwent periods of rapid retreat within the last few centuries, which could be triggered again through melt driven by climate change.
[...] The Thwaites Glacier extends well below the ocean's surface and is held in place by jagged points on the seafloor that slow the glacier's slide into the water. Sections of seafloor that grab hold of a glacier's underbelly are known as "grounding points," and play a key role in how quickly a glacier can retreat.
In the new study, an international team of researchers used an underwater robot to map out one of Thwaites' past grounding points: a protruding seafloor ridge known as "the bump," which is around 2,133 feet (650 m) below the surface. The resulting map revealed that at some point during the last two centuries, when the bump was propping up Thwaites Glacier, the glacier's ice mass retreated more than twice as fast as it does now.
Researchers say the new map is like a "crystal ball" showing us what could happen to the glacier in the future if it becomes detached from its current grounding point — which is around 984 feet (300 m) below the surface — and gets anchored to a deeper one like the bump. This scenario could become more likely in the future if increasingly warmer waters melt away the glacier's guts, according to the statement.
[...] The resulting map showed that the bump is covered with around 160 parallel grooved lines that give it a barcode-like appearance. These strange-looking grooves, which are also known as ribs, are between 0.3 and 2.3 feet (0.1 and 0.7 m) deep. The spaces between the ribs range short and wide, between 5.2 and 34.4 feet (1.6 and 10.5 m) apart, but they are most commonly around 23 feet (7 m) apart.
[...] "It's as if you are looking at a tide gauge on the seafloor," study lead researcher Alastair Graham, a geological oceanographer at the University of South Florida, said in the statement. "It really blows my mind how beautiful the data are." However, the eye-catching grooves on the seafloor are also cause for concern, he added.
Based on the spacing of the ribs, the researchers estimated that when the Thwaites glacier was anchored on the bump, the icy mass retreated at a rate of between 1.3 and 1.4 miles (2.1 and 2.3 km) per year. This means that the glacier was retreating almost three times faster than it was between 2011 and 2019, when it was receding at a rate of around 0.5 miles (0.8 km) per year, according to satellite data.
[...] The new findings are worrying because they show that the Thwaites glacier experienced "pulses of very rapid retreat" even before the effects of climate change increased the current rate of ice loss, Graham said. It shows that the glacier has the potential to accelerate much faster if it becomes detached from its current grounding point and anchors to a subsequent bump-like grounding point, he added.
See also:
The International Thwaites Glacier Collaboration
Orange submarine 'Rán' explores the sea floor in front of Antarctica's Thwaites Glacier
Journal Reference:
Alastair G. C. Graham, Anna Wåhlin, Kelly A. Hogan, et al. Rapid retreat of Thwaites Glacier in the pre-satellite era. Nat. Geosci. 15, 706–713 (2022). 10.1038/s41561-022-01019-9
(Score: 0) by Anonymous Coward on Thursday September 15 2022, @09:25AM
It's a good thing glaciers don't trim their nails, huh?
(Score: 2, Insightful) by bradley13 on Thursday September 15 2022, @09:34AM (18 children)
Well, that's true. It's also true that it wasn't even close to that much. Sea level is currently rising at a bit less than 3mm/year, so over 30 years thats 90mm or about 3.5 inches.
So this is something that happens periodically. Interestingly, within "the last few centuries" there was no time when sea levels rose substantially.
So the glacier is now retreating more slowly than before, ok, understood.
tl;dr: As usual, they are really stretching the evidence, to find some reason to panic. Apparently, you cannot get an article published, if you just present objective evidence without editorializing.
Everyone is somebody else's weirdo.
(Score: 5, Informative) by hendrikboom on Thursday September 15 2022, @09:51AM (13 children)
It's not the part of the glacier that's entirely under water that concerns us. When it melts it will shrink by about ten percent, thereby reducing sea level.
And it's not the part of the glacier that's truly floating that's a concern. It's displacing its own weight of water, and when it melts it'll just turn into that same volume of water.
It's the part of the glacier that's above water and supported by land that's the real worry. When it melts it will raise sea levels.
(Ocean salinity and glacier impurities may affect these statements slightly)
-- hendrik
(Score: 4, Insightful) by pkrasimirov on Thursday September 15 2022, @10:21AM
And the albedo [wikipedia.org].
(Score: 3, Interesting) by bradley13 on Thursday September 15 2022, @11:19AM (8 children)
Yes, I do understand that. And they are concerned that water intrusion underneath the glacier melts the part in the water, causing the part on land to move more rapidly. This is all very valid to study. The thing is: the own evidence and discussion in the article does not support the doomsday language. Note also that NASA documents "Since 1979, the total annual Antarctic sea ice extent has increased about 1 percent per decade." This makes doomsday predictions in Antarctica even more ridiculous.
Even in the Arctic, where there is evidence of warming, one gets tired of the crazy predictions. BBC in 2007: "ice-free summers in 5-6 years", US Navy: "ice-free arctic ocean by 2013", NASA: "Arctic ocean nearly ice-free in 2012", University of Cambridge in 2012: "complete collapse of Arctic ice sheet by 2015-16", and on, and on, and on...
It seems that it is currently impossible to just do science. Scientists must produce dramatic predictions, in order to get published. When these predictions fail? Crickets. Instead, we just get the next round: now the Arctic should be ice free in 2030. Sure, whatever they say...
Everyone is somebody else's weirdo.
(Score: 0) by Anonymous Coward on Thursday September 15 2022, @02:17PM (1 child)
I think you need to provide a bit more context before jumping to that conclusion. The Antarctic is a crazy system with the polar vortex that they have seen both ice growth and the most rapid ice melt at the same time. It looks like the global ice coverage is decreasing, and I believe the sea level height doesn't dispute that. The Antarctic pulses and throbs [pnas.org] and does all sorts of stuff. And as for that 1%, I don't know, you can fit a line through the max extent plot [climate.gov] and get a general increase , but you going to ignore that variability and say "even more ridiculous"? That minimum extend doesn't look like it is increasing, but again look at that variability.
(Score: 1, Informative) by Anonymous Coward on Thursday September 15 2022, @09:51PM
Translated into common US English, "We don't know WTF is going on, but that doesn't stop us guessing!"
(Score: 4, Interesting) by bzipitidoo on Thursday September 15 2022, @04:57PM (5 children)
The predictions aren't crazy. If anything, the best ones have been minimized. Ice sheets most certainly can melt. They did so just 11,700 years ago. Raised sea level over 100m. Then of course there was no civilization. Life was able to adjust.
Now we've been pushing the remaining ice sheets hard towards another huge melt. Obviously they most certainly can melt. The question is, will they, and how soon and how quickly? The odds are alarmingly high. This isn't anything so low as the odds of a dinosaur killer sized asteroid strike, this is much much more likely than that. Any rational person should be scared shitless that it can be very soon and very fast. And it seems some are secretly so scared, they prefer to bury their heads in the sand and ignore it.
I do not feel at all sure our current civilization can withstand the shock and disruption. Our preparations thus far have been feeble. All this noise about building a wall on the US-Mexico border, when a sea wall around the entire state of Florida would've at least been a move towards dealing with a real threat rather than an imaginary one. In any case, I understand a Florida sea wall will not work. We don't have a lot of reserve, preferring, it seems, to greedily consume almost all available capacity. This high value we place on human life, even if only as a pretext for instance with the whole anti-abortion movement branding themselves as "pro-life", may well be one of the biggest casualties. The value of life could easily flip to the negative. If we can't produce enough food to feed everyone, there will be no alternative to death. The only choice will be how? Famine, or war?
(Score: 3, Interesting) by bradley13 on Thursday September 15 2022, @06:33PM (4 children)
Everyone is somebody else's weirdo.
(Score: 2) by bzipitidoo on Thursday September 15 2022, @10:33PM (3 children)
We'd all like to think the predictions are sensationalist drama. I have no doubt con artists are exaggerating, the better to sell their notions that will help a very little and somehow cost a whole lot. I put in that category such pitches as upgrading an older home's single pane windows to double or triple pane, and installing solar panels on the roof. That latter may be worthwhile, for under $10k. But when they ask $35k, that's a hard pass.
So which predictions are you taking about? The prediction that I find trustworthy is the one that says that if we go over 1.5 degrees C of warming, we will see all kinds of trouble. 1.5 degrees C may be the maximum the Greenland ice sheet can take without collapsing.
(Score: 3, Interesting) by bradley13 on Friday September 16 2022, @08:30AM (2 children)
My point is that science is about testing theories. Make predictions, and if your theory is correct, those predictions will come true. If the predictions turn out wrong, then the theory was wrong.
In climate science, all but the most trivial predictions seem to turn out wrong - yet there is no adjustment of the theory. The one I first mentioned: The Arctic will be ice-free by 2008, no 2012, no 2015, no 2018, well maybe now 2030. There's never a retraction or a correction - these failed predictions are just ignored, and the next dramatic prediction is made.
Predictions like "1.5C warming and we are so screwed" are not useful, because they are not testable. What non-trivial, testable predictions about the consequences of global warming have been made, that have proven correct?
Everyone is somebody else's weirdo.
(Score: 2) by bzipitidoo on Friday September 16 2022, @03:56PM (1 child)
> In climate science, all but the most trivial predictions seem to turn out wrong
There are good predictions, and sensationalized, distorted, and exaggerated ones, and downplayed and minimized ones for political reasons. This particular subject is absolutely fraught with politics.
Climate science got the Ozone Hole right. Consider that.
The arctic may not be ice free yet, but the ice sure has been declining. So someone guessed the ice could all be gone as early as 2008. The media eats up the drama, exaggerating it even more, and minimizes the uncertainties because uncertainty is not what people want to hear. They also simplify, too much. They sell their clickbait. Then it doesn't happen, and now a whole bunch of people wrongly dismiss the whole thing.
Meanwhile, the politicians and special interests such as Big Oil try to sell us all a load of "don't worry, be happy" propaganda that is patently self-serving, while accusing scientists of doing the same. The notion that scientists could all conspire together to tell a Big Lie about the climate is absurd. In science, lies don't fly, not for long. They get found out. The bigger the fake finding, the sooner other researchers seek to build on it, and find that they can't. The biggest reason Big Lies do not work in science is that science is very egalitarian. Anyone can do science. Can collect data. In the face of that, a conspiracy to cover up and/or misrepresent facts and findings cannot be maintained, unless the whole world gets on board.
(Score: 1) by khallow on Monday September 19 2022, @04:44PM
Where's the evidence for that? The model for human-caused ozone depletion isn't bad, but we only have 60 years of evidence. Ozone holes like the ones seen over that time might have occurred naturally for the past five million years (ever since Antarctica became ice-bound). Observing something for the first time doesn't mean it happened for the first time.
What's "wrong" about the dismissal? When a field has ongoing Chicken Little problems for decades, that's evidence. Sure the problems may eventually come true, but it's reason to suspect the usual hyperventilation that happens every day in this field.
Propaganda by its nature isn't invisible. So where is this load of propaganda? It's remarkably hard to see.
And consider this phrase in particular:
(For only a few million dollars a year, often dealing with opaque, complex computer models and data adjustments.) It's not like the flat Earthers, who could just conduct a bunch of cheap, easy experiments that would destroy their entire theory in minutes (such as calling people in other parts of the world and finding out where the Sun, Moon, or various stars were located). It takes some serious effort to vet this theory. That's why many of the fallacies in this area (such as arguments from authority/ignorance/obfuscation are so abusive). Not everyone gets considerable government funding to prove the sky is falling.
My take is that the "conspiracy" - such as it is - is unraveling. It's just unraveling for the urgent climate change side. Just look at your above walking back of climate change claims about Arctic ice. My take is that in a few decades we'll have a real idea of how serious a problem climate change is - and I do think there will be some degree of problem. But I think we'll find it's been considerably exaggerated.
They can obfuscate their models and research, but they can't hide the future. That's where we'll fix this.
(Score: 2, Interesting) by khallow on Thursday September 15 2022, @12:03PM (1 child)
Actually, it wouldn't, but facts never stood in the way of a good pants-wetting.
And that's a big part of the problem with these Chicken Little narratives. We're supposed to worry about a potential 10 foot rise in sea level Real Soon Now when we have almost a foot of sea level rise since the beginning of the industrial age?
My take is that humanity can handle an order of magnitude increase in the rate of sea level rise without significant issue. This story claims that Thwaites Glacier can deliver that rate of rise (as well as possibly trigger further sea level rise). We'll see.
(Score: 1, Touché) by Anonymous Coward on Thursday September 15 2022, @01:04PM
Even here with all of 10 commenters the leftists go above and beyond to hide your wrongthink(tm).
Clearly the sky is falling and we must go back to pre-industrial times as a society while only the elites should have fossil fuels and technology. Only the elites can eat meat and you must eat the bugs for the good of planet earth. Unless you live in china or india though, they deserve to experience a high standard of living because of racisms or something like that.
(Score: 2) by JoeMerchant on Thursday September 15 2022, @12:37PM
Time to crank up the snow-blowers! Start freezing that seawater (should be easy on the Antarctic coast!) and blowing it inland to pile up into new "sea level mitigation" glaciers. What could go wrong?!???
Україна досі не є частиною Росії Слава Україні🌻 https://news.stanford.edu/2023/02/17/will-russia-ukraine-war-end
(Score: 3, Interesting) by JoeMerchant on Thursday September 15 2022, @12:36PM
Sea level rise isn't even everywhere. When you get down to a scale of inches, the sea is far from flat and changes in currents, thermal profiles, etc. can vary mean sea level by a foot or more. As the climate changes, sea level is rising almost everywhere, but it's much faster and further in some places than others - on a scale of inches.
Україна досі не є частиною Росії Слава Україні🌻 https://news.stanford.edu/2023/02/17/will-russia-ukraine-war-end
(Score: 2, Troll) by Captival on Thursday September 15 2022, @01:35PM (1 child)
Hey you. Stop having unauthorized opinions other than "AHHHH Everything is terrible give more money to communists!!!". You're lucky this isn't Twitter or Facebook, where it would be quickly flagged for blasphemy.
(Score: 0, Touché) by Anonymous Coward on Thursday September 15 2022, @04:51PM
To which "communists" [wikipedia.org] are you referring?
No government I'm aware of is working this angle. Not even the Chinese.
So please, do tell. Who the hell are you talking about?
(Score: 5, Funny) by Username on Thursday September 15 2022, @01:43PM
Yes, but you should be worried about the possibility that if it breaks free and nazis sail it to Europe and fire giant cannons from it, then wedge it between France and the Uk and launch a full scale penguin invasion. You need to be afraid. So very afraid.