Unavoidable future increase in West Antarctic ice-shelf melting over 21 century(nature.com)
nature.com
Unavoidable future increase in West Antarctic ice-shelf melting over 21 century
https://www.nature.com/articles/s41558-023-01818-x
42 comments
Whenever I think of Geo-Engineering I imagine someone getting into keeping reef aquariums, noticing some fish are looking less than healthy, testing and seeing chemical/physical properties of the tank are off, adjusting by adding/removing some chemical only to see everything die anyway, and then coming to the realization that maybe this hobby is a lot more nuanced then they imagined and isn’t for them.
Perhaps next time we’ll just get a freshwater planet, I hear those are much more forgiving ;)
Perhaps next time we’ll just get a freshwater planet, I hear those are much more forgiving ;)
I don't understand this US mentality that some more tech will save us. It's some some of blind headlong rush to our demise, just to ignore the fundamental problems:
- too many humans
- too much pollution
- too much energy consumption
- too many humans
- too much pollution
- too much energy consumption
I agree. And the solutions to all of those are very simple but entrenched interests in economic growth seem to be in the way. We should be championing the natural decline in birthrates and start planning for a new economy based on the changes that will bring.
Honestly I partially blame advertising in general. We are all constantly reminded that we should want more, that we never have enough, and are offered solutions to problems that we didn't view as problems to begin with putting us in constant competition with one another. I think we will end up happier overall when we stop pursuing consumer growth and start pursuing human connections realizing that the things most of us want are not produced in a factory or presentaed on a screen.
Honestly I partially blame advertising in general. We are all constantly reminded that we should want more, that we never have enough, and are offered solutions to problems that we didn't view as problems to begin with putting us in constant competition with one another. I think we will end up happier overall when we stop pursuing consumer growth and start pursuing human connections realizing that the things most of us want are not produced in a factory or presentaed on a screen.
Fucked is not a binary. The choice now is between majorly fucked and severely fucked.
Severely fucked is human extinction?
We survived the ice age with a lot less than we have now. I can’t foresee the population staying as high as it is but human extinction won’t happen imo.
Ummm... During the ice age, did humanity have any literal lunatics in charge of any weapons of mass destruction, capable of wiping out entire cities at the push of a button? Weapons that could alter the state of natural weather systems? Weapons that could unleash diseases or poisons on global scales? Sure, humans have survived nature in the past, but this is humans with really deadly technology this time around. Even if we survive this, what's the stupidity of warmongers with those sorts of weapons gonna do to the world during the ensuing chaos? Will it be a world worth living in anymore, or will we wish we'd died with the rest?
That's terminally fucked. Severely fucked would (imho) be a complete breakdown of order and anything larger than local infrastructure.
Mass migration, I think. We'll lose and gain livable land mass, and I don't recall if the net is positive or negative.
I find the fear of mass migration a funny one to be championed by the left(who do the heavy lifting for climate change response, at least in the US), considering their, at best, "meh" reaction to the mass migration that is already happening across the US southern border.
There is no contradiction between wanting migrants treated humanely and wanting fewer people forced to become migrants. The more migrants there are, the worse they are treated.
I don't believe the fear/apprehension is specifically about immigration of peoples, but the likelihood that we'll see intergroup conflicts (fuelled by fear mongering rhetoric that usually follows), as well as the fact that these peoples –who are least poised to handle the challenges of global warming– are being displaced in the first place.
The left prefer people don’t have to migrate, but that they can seek asylum when they need to
Tipping points and feedback loops are meaningless to techno-utopians, in their eyes nothing is fundamentally different between climate change and other technical challenges in the past
Additionally, even if we could remove carbon from the system scale, it's not like everything would magically reset to where it was. We are seeing changes (e.g. extinctions) that aren't really undoable.
With that said, I'm sure that some of the damage can potentially be reversed, and the planet has some capacity to self-heal over long periods of time.
Hopefully reducing emissions and even partial decarbonization will lead to a less bad outcome in the medium to long-term.
With that said, I'm sure that some of the damage can potentially be reversed, and the planet has some capacity to self-heal over long periods of time.
Hopefully reducing emissions and even partial decarbonization will lead to a less bad outcome in the medium to long-term.
I got accused of being a Luddite because of my (negative) response to a post about SpaceX launching rockets every 2.5 days. There are reasons, beyond being a Luddite, for being against such enterprises.
Elon promised to switch to a carbon-neutral fuel (methane synthesized from atmospheric carbon). It'd be nice if some agency actually held him to that promise.
Where do they get the energy for the synthesis from?
Nothing but solar makes any sense, environmentally or economically.
Example: https://terraformindustries.com/
Example: https://terraformindustries.com/
It would be interesting to "store" solar energy as synthesized fuel. The efficency would probably be abysmal, but definitely interesting.
> It'd be nice if some agency actually held him to that promise.
And then what do they do if he does not? SpaceX is a sacred cow.
And then what do they do if he does not? SpaceX is a sacred cow.
People telling me I’m a Luddite is just making me more and more of a Luddite.
It's a terrible, interesting time we are leaving our collective children and grandchildren. There will have to be a mass migration, where possible, since so many people live or work within that zone of sea water rise.
They also need to adjust this map viewer thing to go to 20 feet.
https://coast.noaa.gov/slr/
They also need to adjust this map viewer thing to go to 20 feet.
https://coast.noaa.gov/slr/
The focus on sea level rise is a huge mistake. We need to be focusing on what this is going to do in terms of food production. People will be more alarmed from starvation than having to move away from the coast.
It should be talked about but I do not think it matters since the fact of human influenced climate change happening has been politicized so a large percentage of people have as a matter of their political identity need to deny it and stop any effort to mitigate it, so they won't change their behavior or voting habits even on the point of it directly make them un-housed (this is from listening to interviews with people who got flooded out of their homes from last hurricane to hit Florida) or hungry. It's a long term problem in our short term focused society. So far the only free market reaction is home insurance being set much higher or cut off in Florida for extreme weather risk and California for fire risk. We in the USA probably won't do anything drastic until things get very dire directly for tens of millions of people in the USA or maybe tens of millions of people to die, since we have already shown to be okay with approximately a million excess deaths from COVID-19 so far.
Humanity got our act together on CFC's and the ozone layer hole but fossil fuels has so many vested interests it's a hard nut to crack.
Humanity got our act together on CFC's and the ozone layer hole but fossil fuels has so many vested interests it's a hard nut to crack.
my hometown is so low the contour maps have no contour lines on them. I've recently heard neighbours chatting about not being able to afford flood insurance.
I have friends who still believe climate change is an academic ploy for funding liberal universities - given our barely higher than high tide elevation, I understand the longing in their denial. Jacked premiums are the first event I've encountered that moves acknowledgement/denial of global warming from a lifestyle/personal identity choice into unignorable.
Might need to do a bit of geoengineering on the side. I hear upper atmosphere SO2 does wonders for atmospheric cooling (and yes, Neal Stephenson has written a book about it).
Apologies for the slightly dark take. But either it’s humor or despair and I refuse to choose the latter out of principle.
Apologies for the slightly dark take. But either it’s humor or despair and I refuse to choose the latter out of principle.
How do you know what signs represent post-tipping point and what don't? It would take some heavy duty physics and meteorology to know one way or the other, no?
Living in South Texas it sure feels like something changed this year; I've never seen so many trees die.
If we are unable to determine the point of no return, then perhaps that would be good reason to stop changing the carbon content of the only planet we can occupy, but I have also come to believe that the changes to come are inevitable and likely terrible.
If we are unable to determine the point of no return, then perhaps that would be good reason to stop changing the carbon content of the only planet we can occupy, but I have also come to believe that the changes to come are inevitable and likely terrible.
> Living in South Texas it sure feels like something changed this year; I've never seen so many trees die.
> If we are unable to determine the point of no return, then perhaps that would be good reason to stop changing the carbon content of the only planet we can occupy, but I have also come to believe that the changes to come are inevitable and likely terrible.
Problem is what if are already past point of no return and extinction of human race is inevitable? And all we can do is postpone it? Would releasing such info help anyone or would only hasten fall of our civilization?
We just don't know what big corporations hide in their research, like they hidden similar stuff in the past?
> If we are unable to determine the point of no return, then perhaps that would be good reason to stop changing the carbon content of the only planet we can occupy, but I have also come to believe that the changes to come are inevitable and likely terrible.
Problem is what if are already past point of no return and extinction of human race is inevitable? And all we can do is postpone it? Would releasing such info help anyone or would only hasten fall of our civilization?
We just don't know what big corporations hide in their research, like they hidden similar stuff in the past?
Personally I think people should stop having children and prepare humanity for an orderly winding down, but that seems pretty unlikely on a number of levels. I suppose we all have to live in denial of our inevitable demise because how else would we get out of bed in the morning? It seems collectively we'll just continue to ignore the problems until they consume us.
Doom-mongering--correct or not--doesn't add to the debate.
I'm not familiar with the latest research, but the WAIS has long been recognized as the biggest potential contributor to severe sea-level rise due to the marine ice-sheet instability, which it is uniquely vulnerable to.
Ice sheets are basically big domes of ice that flow outward under their own weight. Little surface melt occurs in Antarctica, while snow continues to fall. To maintain approximate mass balance, most of the mass is lost to the ocean. Most of the WAIS bed is below sea level, but the ice is thick enough that the ice rests on the bed, and seawater is excluded. Where the ice sheet begins to float is where ice shelves or calving happens. Towards this margin, the outlet ice streams are almost but not quite floating. They have little friction at their beds, but they push up sediment in front, forming sediment wedges that push back on the grounded ice behind them. This slows the outward flux of ice, and creates a stable equilibrium as the ice pushes up against the wedge.
Much of WAIS is on a reverse bed, where the bed drops in elevation as you proceed inland (despite the ice getting thicker, and the top of the ice sheet getting higher and higher). Due (largely) to increased submarine melting leading to thinner ice shelves (which themselves push back due to pressing up against islands and such), the ice grounding line can retreat from the wedge. Worse, this enters a feedback: due to the reverse bed, the ice is now thicker in the new retreated grounding line, because flotation occurs in deeper water. This increases ice flux due to the thicker front. Thus retreat accelerates more, and so on until the ice sheet collapses.
Ice sheets are basically big domes of ice that flow outward under their own weight. Little surface melt occurs in Antarctica, while snow continues to fall. To maintain approximate mass balance, most of the mass is lost to the ocean. Most of the WAIS bed is below sea level, but the ice is thick enough that the ice rests on the bed, and seawater is excluded. Where the ice sheet begins to float is where ice shelves or calving happens. Towards this margin, the outlet ice streams are almost but not quite floating. They have little friction at their beds, but they push up sediment in front, forming sediment wedges that push back on the grounded ice behind them. This slows the outward flux of ice, and creates a stable equilibrium as the ice pushes up against the wedge.
Much of WAIS is on a reverse bed, where the bed drops in elevation as you proceed inland (despite the ice getting thicker, and the top of the ice sheet getting higher and higher). Due (largely) to increased submarine melting leading to thinner ice shelves (which themselves push back due to pressing up against islands and such), the ice grounding line can retreat from the wedge. Worse, this enters a feedback: due to the reverse bed, the ice is now thicker in the new retreated grounding line, because flotation occurs in deeper water. This increases ice flux due to the thicker front. Thus retreat accelerates more, and so on until the ice sheet collapses.
An Antarctic ice melt leading to a 5m global sea-level rise would render London's Thames Barrier obsolete. We're talking about a threat that could manifest by 2050 if climate targets aren't met. The engineering challenge to upgrade or replace the barrier is colossal, think at least £10 billion just for the engineering, not factoring in the social costs.
Add land acquisition in London's expensive real estate market, and the relocation of communities, you could easily double or triple that cost. To put it in perspective, this could rival or surpass projects like the Channel Tunnel in terms of financial and logistical complexity.
And yet, there's a startling lack of political and public dialogue on this urgent issue. This isn't just about engineering; it's about national security and public safety. The disconnect is alarming.
Add land acquisition in London's expensive real estate market, and the relocation of communities, you could easily double or triple that cost. To put it in perspective, this could rival or surpass projects like the Channel Tunnel in terms of financial and logistical complexity.
And yet, there's a startling lack of political and public dialogue on this urgent issue. This isn't just about engineering; it's about national security and public safety. The disconnect is alarming.
The conclusion:
policymakers should be prepared for several metres of sea-level rise over the coming centuries. [...] Limiting the societal and economic costs of sea-level rise will require a combination of mitigation, adaptation and luck.
> These results suggest that mitigation of greenhouse gases now has limited power to prevent ocean warming that could lead to the collapse of the West Antarctic Ice Sheet.
What makes these new projections different from those of recent decades?
> It has been hypothesized that Amundsen Sea warming will respond to future climate change and may be amenable to mitigation by reducing greenhouse gas emissions6,9,10. However, this hypothesis has not been adequately tested. Existing future projections of ice-shelf basal melting are generally not reliable in the Amundsen Sea, a region which is frequently biased cold or poorly resolved in the underlying ocean models11,12. Reference 13 produced the first future projections using a regional model of the Amundsen Sea, which simulated an increase in basal melting. However, this study only considered a single forcing scenario, the worst-case scenario of extreme fossil fuel use, and did not account for internal climate variability.
If you were to say "they have just decided to go with the most alarming scenario possible and throw the scientific method to the wind" I think it would fit the description in the abstract.
If you were to say "they have just decided to go with the most alarming scenario possible and throw the scientific method to the wind" I think it would fit the description in the abstract.
measurements
Its growing abundantly clear that the tipping point is well in the past.
Decarbonization must proceed, of course, but if we can't feasibly remove carbon from the system at scale, we're well and truly fucked.