Doomsday Glacier melting in Antarctica means terrible news for global sea level rise

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It is good that Space.com treats reality seriously. Given the reality and seriousness of global warming it is important to understand how Antarctic ice sheet loss can and will contribute to sea level rise, which will increasingly impact people living in low lying places. And progressively impact places that are currently not at risk of inundation.
Treating a profound problem of global scale that will seriously harm our capacity for enduring prosperity in irreversible ways like it is serious isn't "climate porn".
 
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Feb 18, 2023
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You can tell a lot about a theory by how it responds to its predictions being tested.
This seems like an easy one: Glaciersmelts=2foot sea level rise.
Ready… set… test!
 
Feb 19, 2023
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What a lie ... Al Gore propaganda is ridiculousness at it's finest. Climate change is just a ridiculous statement that ignorant people can't grasp. The earth has gone through multiple changes throughout Earth's geological history. Most of which is due to Solar Maximum and Minimum activities. And pole shift events that were way before any industrial pollution supposedly causing all this. It's just plain naturally occuring. Stop trying to fear monger people who probably got C's and D's in science class. Who believe anything their told by supposed experts on the subject. Pick up a book for God's sake, and practice REAL SCIENCE and research. Doomsday glacier sure , but it'll be hundreds of not thousands of years from now.
 
Sep 11, 2022
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It's so easy to signal that you belong to the "right" set of people -- the virtuous, the altruistic, the "follow the science" crowd. Just knock off a couple of lines of pompous blathering while trampling all over the scientific method. It gives meaning to your otherwise pathetic, miserable life bereft of accomplishments.

I wish I could simply ignore you clowns, but unfortunately you just won't leave me alone. So I will keep skewering your bombastic "doomsday" language and I will keep mocking you, for mockery is the best weapon currently available against you. Screw you if you cannot handle it.
 
It is amusing to see people posting about "natural cycles" as a reason to not believe that sea level will rise. The geologic evidence of the high point in those natural cycles 120,000 years ago indicates that sea level rose, with no human causes, to a level 25 feet higher than it is, today. So, no matter what you think the cause is, there is no good reason to expect sea level to not rise a lot in our future. How fast it does so, and when it will stop, are the main questions. Other warm periods in the last few million years have resulted in max sea level rises of as much as 65 feet higher than now. And, back several million years, before the current series of ice ages and warm periods started, sea level was hundreds of feet higher than it is now. If all of the ice caps and glaciers melt, sea level will be about 330 feet higher than it is right now.

So, this article is just looking at some of the melting mechanisms for one glacier at one point in time. And, it doesn't say how fast it is predicted to happen. So, not really much useful info. In fact, it seems to indicate that humans might somehow stop the melting.

Probably not. Much of the melting is due to the cycles of the Earth's orbital precession and axis tilt precession. And the current parts of those cycles are heading towards more warming in the Antarctic and less in the Arctic.

So, in reality, we need to be planning for substantial sea level rise even as we try to cut our human effects on the climate.
 
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In fact, it seems to indicate that humans might somehow stop the melting.
Every low sea level rise projection depends on success at emissions reduction with minimum of delay. Glacier and ices sheet mass loss acquire a momentum that makes stopping them (by reducing human-made climate forcings) progressively more difficult in the early stages and effectively impossible later. The collapse of Thwaites would take us into too late to stop territory. But not too late to make things worse, by confusing too late to stop happening with can't prevent more and worse.

It is amusing to see people posting about "natural cycles" as a reason to not believe that sea level will rise.
Past climate changes provide examples of both how susceptible and how world changing climate change can be. They aren't evidence that current warming is natural or harmless. Climate science deniers are often unmoved by facts or reason and ultimately descend into conspiracy theories - because how else can every science agency that studies climate keep saying it is real and very serious? And get all those satellites that show evidence of a warming world to agree too? Even Intelligence Agencies - that appear to agree the science is sound and the climate problem is serious - are in on it?

Sorry the real conspiracy is to sustain an ongoing absence of inconvenient responsibility or accountability for the biggest human-made waste stream - CO2 - and the problems it causes. Conspiracy theories that seek to blame the messengers - scientists, science agencies and those taking them seriously and calling for appropriate government coordinated national and international responses. Those taken in by it don't amuse me.

Much of the melting is due to the cycles of the Earth's orbital precession and axis tilt precession.
Where did you pull that out of?
 
Much of the melting is due to the cycles of the Earth's orbital precession and axis tilt precession.

Where did you pull that out of?

Ken , the intent of that particular sentence in my post was a response to the previous posts that talked about other natural cycles (e.g., "Solar Maximum and Minimum activities. And pole shift events"), which have little-to-nothing to do with global climate. Yes, there are theories that somegthing like a grand solar minimum might trigger an ice age, but even if true, it would be in relation to the climate being set-up for it by the Milankovitch Cycles in the Earth's orbital and rotational precession patterns.

And the point I was trying to make is that, if somebody really is a believer in the effects of the natural cycles playing a role in how the climate is warming, today, then he/she should note that those cycles are currently shifting towards more solar energyt going into Antarctica and less into the Arctic at this time and into the future for quite a while. So, the conclusion should still be that the sea level is going to rise due to melting of Antarctic glaciers. How the specific glaciers behave is just details of the overall process.

So, yes, the article was click-bait in the way it is worded. And the implications of the wording, that we might be able to stop the process, seems unproven and unlikely, at this point. And the timing was not quantitatively predicted in the article. I will note that the latest "best guesses" published elsewhere are showing a higher sea level in the next 30 years than previously estimated. So, there is some concensus building that the rate of sea level rise will be accelerating shortly by noticeable amounts.

I am not arguing that humans aren't contributing to the projected acceleration of the sea level rise rate. I am just arguing that we need to stop publishing articles that imply we can stop the rise if we just do [fill in the blank with your agenda].

Frankly, I think it is probably better communication of the reality and severity of the sea level situation for the governments to be seen to be actively planning for that future, instead of just using it as a scare tactic and implying that the whole thing can be avoided. My own planning is that my present home may become unlivable with greater and greater probability over the next few decades, with the actual transition date depending on when a hurricane with the actual devastating effects hits here instead of somewhere else. It could happen this summer . It probably will happen in the next 30 years.

Anyway, sea level rise is not the only effect we need to worry about happening due to global warming. It is just the easiest one to predict and measure. Looking at atmospheric pattern changes is more complicated because there are many other short-to-medium-term changes adding "noise" to the trend lines. For instance, the Anaszi culture in the U.S. southwest seems to have been extinguished by a centuries-long shift in rainfall in that region, long before the industrial revolution. So, it is difficult to look at the current drought in the southwest as clearly due to global warming caused by humans. Hard to prove it is or is not.
 
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I am not arguing that humans aren't contributing to the projected acceleration of the sea level rise rate. I am just arguing that we need to stop publishing articles that imply we can stop the rise if we just do [fill in the blank with your agenda].

So, without any evidence you want to claim that Milankovitch cycles - that act very slowly over 10's of thousands of years - are responsible for significant changes to Antarctic ice sheets within the last century, that they are a significant factor in the current observable rapid acceleration of ice mass loss. You are arguing without evidence that there is a significant natural component to Antarctic ice mass loss, that therefore attribution to human causes is exaggerated.

The "agenda" is preventing economically and environmentally damaging climate change.

Sure, if you hand the issue over to others who do have other agendas in "you care so much, you fix it" style you can conveniently argue it is their other agendas that prevents you from supporting commitments to mitigate the problem but the science based advice has been the same advice irrespective of political leanings. By choosing to face up to it head on you can promote the means you think best - including your own agendas. No-one is stopping you.

Climate activism only leans green and left because of failure of those who don't lean green or left to participate constructively - and chose instead to oppose and obstruct. That opposing hasn't been to prevent unreasonable left leaning extremism but to prevent legitimate accountability applying to commerce and industry.
When those who lean right come out from behind the Wall of Denial and face up to the climate problem with eyes open, head on, we will begin seeing more constructive climate policies that are much more effective.
 
Ken, I am going to just skip over your mislabeling of me and my position and go to the science where you are missing an important point. You posted
So, without any evidence you want to claim that Milankovitch cycles - that act very slowly over 10's of thousands of years - are responsible for significant changes to Antarctic ice sheets within the last century, that they are a significant factor in the current observable rapid acceleration of ice mass loss. You are arguing without evidence that there is a significant natural component to Antarctic ice mass loss, that therefore attribution to human causes is exaggerated.

What you seem to be missing is that there is strong evidence that that Milankovitch Cycles play a major role in the ice age / warm interglacial periods that dominate the earth's climate over the last few million years. (But I am not claiming that they dominate now, after humans have had substantial impacts.) In particular, the geologic evidence is that there was a huge amount of ice melt, starting about 25,000 years ago, when there were ice sheets (similar to what is now on the Antarctic and Greenland areas) that covered much of North America and northern Europe/Asia. Ice sheets 2 miles thick melted over a period of a maybe 10,000 years, raising the ocean level by about 325 feet. Then, the sea level became more stable, but not perfectly static.

So, without any effect from human industrializatiton, Earth has previously and relatively (geologically) recently experienced rapid melting of large ice sheets. And, in previous warm periods over the last few million years, the sea level reached higher than it is now by several tens of feet, before going back down again as the northern continents began building ice sheets, again. I don't have numbers handy for the peak sea level rate of rise during the last big melt, but if it was averaged over 10,000 years, it would be 0.4 inch per year. So, it is a good bet that the peak rate was in the inches per year range. With some of the huge ice dam breach theories for those melts, it isn't unlikely that there were episodes where sea level may have risen by feet in a year.

Those interglacial sea level records indicate that there was a lot of variablity in the warm periods, so the geologica record really doesn't help us precisely predict what would have happened during the current warm period if humans had not had any effects. And, the last I looked, nobody has made a computerized climate model that can "backcast" the climate to match the geological evidence. So, we are not in a good position to say exactly what the climate would be doing right now if humans were not here, doing what we are doing and have already done.

About the best geologic evidence for the net effects of human impacts comes from comparison of atmospheric CO2 levels over the last 10 million years. Before the ice age cycles that started about 3 million year ago, there was more CO2 in the atmosphere. And there was different circulation in the ocean. In particular, the Central American isthmus had not risen above the sea level then, so the Atlantic and Pacific were connected between South and North America. It is theorized that a combination of CO2 removal by rock weathering and changes in atmospheric and oceanic circulation patterns is what started the ice age cycles (with both having been driven by techtonic activity raising mountains). And, the cold periods had been getting stronger, having started with warm periods roughly every 50,000 years, they started skipping warm periods and went to one roughly every 100,000 years about 900,000 years ago. So, humans arteficially increasing CO2 in the atmosphere is believed to be a major disruption of that cycle process. Because the current CO2 levels are approaching the levels that occurred before the ice age cycles began several thousand years ago, it is reasonable to think that human activity may have ended the ice age cycles.

So, it is reasonable to believe that the average climate will go back to something similar to what existed several million years ago. That would mean sea level hundreds of feet higher than it is right now, maybe as much as 300 feet higher. That will, by itself, wipe out most of our current technological infrastruture. And the climate will change to make Canada and Russia more pleasant and productive, while having negative effects on tropical regions.

But, that will take hundreds to thousands of years. Humans can adapt, and human cultures can adapt. The big question is will we adapt in a constructive or destructive manner. History seems to indicate that we are our own worst enemies, and will tear down each other's civilizations as we compete for resources. That might mean the end of things like space telescopes and the return to a brutal existence for surviving humans.

How humans fare in the changing environment is of course the main topic for human discussions. But, Earth has gone though much more cataclysmic events, and life has persisted and evolved in spite of them, and maybe even because of them. So, I am not agreeing with the people who think we are about to turn Earth's environment into something like what we see on Venus.
 
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I thought the article was nicely written. The video showing how calfing takes place is nicely done as well, which shows the warmer sea water melting the underbelly of the glacier.

What is missing, however, is the cause of the warmer sea water. The greatest concentration of volcanos in the world seems to be along this Antarctic ridge. There are 138 known volcanos in western Antarctica, including some in the thwaites glacier region.

C02 levels may or may not have much to do with this melting. It's just another example where we need better science and discussions that address all the known and other potential variables, and their dependent and independent relationships with one another. There are several known variables that will likely get incorporated in the models in the future, but the science to do this right is still a work in progress.
 
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Helio, I do agree that the article was interesting and informative. But using language like "Doomsday Glacier" is politics, not science. The article itself says:

" The collapse of Thwaites would cause seawater levels to rise by around 2 feet (65 centimeters). This could, in turn, destabilize neighboring glaciers, potentially increasing future sea levels by almost an additional 10 feet (3 meters)."

Considering that the sea level was 25 feet higher than now in the last intergacial period, about 120,000 years ago, even a 10 foot rise does not seem like "dooms day". And, it is not as if there would be a sudden tsunami that drowns people all around the world - it will take a long time for the sea level to rise as Antarctic and Greenland glaciers melt.

If there is any sort of "doom" related to that sea level rise, it probably will come from humans' responses to the shifts in our societies that it will force us to make. If we do our typical thing and fight each other for territory and resources, we may very well create our own doom. The last time the sea level was so high, there were far fewer humans on Earth, and there was no chance for nuclear war as whatever migrations needed to occur took place. But, I expect it still created conflicts that were not recorded in pre-history.
 
Helio - So, without any evidence that volcanic activity around and below Antarctica has increased and with abundant evidence of rapid global warming you want to attribute accelerating ice loss to volcanic activity.

Unclear Engineer - for a lot of people even 2ft of global average sea level rise would be disastrous. If studies show that as possible as a relatively near term impact it is important that policy makers as well as public are aware.

The difference between those past sea level changes and now is that global warming will affect people now living. And appointed and elected policy makers do have duties of care to take the expert advice seriously and consider the impacts to those people.
 
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