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Bye Bye Humanity: The Potential AMOC Collapse

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Re: Bye Bye Humanity: The Potential AMOC Collapse

#61

Post by danaris »

roenxi wrote: post #50
PinkMilkshake wrote: post #43

Earlier quoted context omitted.

> humans cope pretty well over a wide variety of temperatures. That's not the problem, though. The problem is almost nothing else can. Livestock, staple crops, pollinating insects, etc.

How big a problem is that over a multi-decade time horizon? There is a pretty big variation in average temperatures by country [0]. Somehow People everywhere from Thailand to Greenland manage to find food. All else failing it is a possibility to trade for calories. Let alone technology improvements that might save the day by accident. I mean, it might make places uninhabitable over the course of a few generations, bu…

Right, and we know that modern human societies are really good at planning for a major disaster on a multi-decade time horizon! Look at how well we've dealt with the climate cri—oh, wait.

This won't end humanity, no. But it is likely to cause absolutely catastrophic levels of upheaval and probably billions (with a b) of deaths—from famine, disease, exposure, and war.

Re: Bye Bye Humanity: The Potential AMOC Collapse

#62

Post by danaris »

lelanthran wrote: post #54
bawolff wrote: post #37

Earlier quoted context omitted.

Being cold doesn't seem that big a problem. I think the bigger concern is what sudden climate shifts might do to agriculture. If some farmland becomes much less viable on a wide basis, that might be much harder to adjust to on the short term. I can't help but think of all the historical societies that collapsed due to even mild pressure on the food supply.

> I can't help but think of all the historical societies that collapsed due to even mild pressure on the food supply. They didn't have the logistical advantages we have today (storage and transport). Okay, when prawns fished from the coast of Mozambique are no longer viable some other spot will, necessarily, become viable. Historical societies did not have the technology to simply farm in another place when their cur…

> some other spot will, necessarily, become viable.

What is your basis for this claim?

It's entirely possible for prawns fished from the coast of Mozambique to simply...go extinct. For areas with good arable land to be plunged into inhospitably cold temperatures, only for other areas with arable land to be made too hot to reliably support their crops.

There's no cosmic balance being kept here.

Re: Bye Bye Humanity: The Potential AMOC Collapse

#63

Post by tasuki »

lelanthran wrote: post #54
bawolff wrote: post #37

Earlier quoted context omitted.

Being cold doesn't seem that big a problem. I think the bigger concern is what sudden climate shifts might do to agriculture. If some farmland becomes much less viable on a wide basis, that might be much harder to adjust to on the short term. I can't help but think of all the historical societies that collapsed due to even mild pressure on the food supply.

> I can't help but think of all the historical societies that collapsed due to even mild pressure on the food supply. They didn't have the logistical advantages we have today (storage and transport). Okay, when prawns fished from the coast of Mozambique are no longer viable some other spot will, necessarily, become viable. Historical societies did not have the technology to simply farm in another place when their cur…

It will become easy to keep things frozen!

Re: Bye Bye Humanity: The Potential AMOC Collapse

#64

Post by roenxi »

SupremumLimit wrote: post #53
roenxi wrote: post #50

Earlier quoted context omitted.

How big a problem is that over a multi-decade time horizon? There is a pretty big variation in average temperatures by country [0]. Somehow People everywhere from Thailand to Greenland manage to find food. All else failing it is a possibility to trade for calories. Let alone technology improvements that might save the day by accident. I mean, it might make places uninhabitable over the course of a few generations, bu…

[flagged]

> Multi-decade time frame can only be thought of as catastrophic when it comes to change of this magnitude.

If someone moves from Singapore to Poland is that a catastrophe? We'd be talking a smaller temperature delta than that and this is still a theoretical risk. That isn't necessarily something that people worry about beyond saying "it is very hot" or "it is very cold". It doesn't have a lot of implications beyond needing to move crops around and changing building standards (which is achievable over long periods of time).

Now just a 10-15 degree swing isn't the end of the story because if the average temperature crosses 0 that might well be a big problem. I dunno. But it sounds solvable, these aren't particularly scary scenarios being put forward. They're more of the expensive and inconvenient variety.

Re: Bye Bye Humanity: The Potential AMOC Collapse

#65

Post by lelanthran »

danaris wrote: post #62
lelanthran wrote: post #54

Earlier quoted context omitted.

> I can't help but think of all the historical societies that collapsed due to even mild pressure on the food supply. They didn't have the logistical advantages we have today (storage and transport). Okay, when prawns fished from the coast of Mozambique are no longer viable some other spot will, necessarily, become viable. Historical societies did not have the technology to simply farm in another place when their cur…

> some other spot will, necessarily, become viable. What is your basis for this claim? It's entirely possible for prawns fished from the coast of Mozambique to simply...go extinct. For areas with good arable land to be plunged into inhospitably cold temperatures, only for other areas with arable land to be made too hot to reliably support their crops. There's no cosmic balance being kept here.

> It's entirely possible for prawns fished from the coast of Mozambique to simply...go extinct.

So? That isn't an irreplaceable staple, is it? Those prawns can be replaced by food that is grown in other places that are viable, whether newly viable or always viable is irrelevant.

> For areas with good arable land to be plunged into inhospitably cold temperatures, only for other areas with arable land to be made too hot to reliably support their crops.

I find it unlikely that all areas become non-arable at the same time. Not even the most extreme warnings about climate change go to this extreme.

What is your reasoning for considering a possibility so small that it exceeds all the most extreme models we have?

Re: Bye Bye Humanity: The Potential AMOC Collapse

#67

Post by metalman »

The sattelite feed links below update every day or more often, and show varios views and visual data of what is happening in the North Atlantic. I have watched for years, and the last few years are markedly different.The SST (sea surface temerature) charts are especialy interesting as these provide a real time visual representation of the amount of heat in the system (earth surface), and watching things like major weather events like hurricanes or polar vortexes exhanging heat with the ocean is also interesting. Depending on conditions things like the gulf stream itself can up in the visible light images from the GOES sattelite and things like sea ice can be corelated in multiple sattelite feeds that show the direct conection between seaice, and ocean currents in real time, superimposed on past conditions. My conclusions are, that there is more heat and less ice, and much more mixing of water bodys, where it looks like heat builds and builds untill some threshold is reached and then hot and cold currents interact suddenly and then reach a new equalibrium. By suddenly I mean in a ridiculously fast movement of bodys of water the size of continents....takes a few days. Most of these feeds have been running in the same format for decades and I suppose I now have more than 1000 hr's observing, every morning with my coffee, my phone working as a 50 billion dollar front seat on the planets reactions to our activities. Very cool, and strange to watch as things start to look serious.

https://weather.ndc.nasa.gov/goes/

https://www.ospo.noaa.gov/products/ocean/sst/contour/

https://nsidc.org/sea-ice-today

https://climatereanalyzer.org/clim/seaice_daily/?nhsh=nh

Re: Bye Bye Humanity: The Potential AMOC Collapse

#68

Post by danaris »

lelanthran wrote: post #65
danaris wrote: post #62

Earlier quoted context omitted.

> some other spot will, necessarily, become viable. What is your basis for this claim? It's entirely possible for prawns fished from the coast of Mozambique to simply...go extinct. For areas with good arable land to be plunged into inhospitably cold temperatures, only for other areas with arable land to be made too hot to reliably support their crops. There's no cosmic balance being kept here.

> It's entirely possible for prawns fished from the coast of Mozambique to simply...go extinct. So? That isn't an irreplaceable staple, is it? Those prawns can be replaced by food that is grown in other places that are viable, whether newly viable or always viable is irrelevant. > For areas with good arable land to be plunged into inhospitably cold temperatures, only for other areas with arable land to be made too ho…

> Those prawns can be replaced by food that is grown in other places that are viable, whether newly viable or always viable is irrelevant.

But those prawns are gone. The people whose livelihood depended on them have lost that. The people for whom they were a staple have lost that, no matter how replaceable they may be.

Sure, given time, we may be able to find replacements for the things we lose to this drastic climatic shift. But that's not a guarantee, and even if we do, there's huge damage and upheaval in the meantime.

> I find it unlikely that all areas become non-arable at the same time.

It's not about "all areas". Nowhere did I say that everywhere on the planet would become non-arable land at the same time. It's about having more land lose viability than gains it within a short span of time.

What you're positing—that as various areas of the planet warm and cool, there will be perfect balance in what arable land we lose and gain—seems much, much less likely than the scenario where land we have farmed for literally thousands of years becomes wasteland, and we do not immediately gain enough new arable land in other areas to replace it. In fact, every projection I have seen has suggested that while we may gain some new arable land, it will be much, much less than what we lose in a scenario like the one described.

What it looks like to me is that you are either handwaving the decades (or more!) of turmoil, hardship, and loss of life for people in the areas that will be most affected by this, or you're engaging in seriously magical thinking to posit that every acre of farmland lost will be perfectly balanced by an acre of farmland gained somewhere else, and no one will be seriously negatively affected by the move from one to the other.

Re: Bye Bye Humanity: The Potential AMOC Collapse

#69

Post by lossolo »

roenxi wrote: post #15
shrubby wrote: post #4

This scary, yet almost nothing on the news. We're living in a fake world and pretending everything is fine. Adam Curtis made a movie HyperNormalisation and we're living it also today. Adam Curtis: “HyperNormalisation” is a word that was coined by a brilliant Russian historian who was writing about what it was like to live in the last years of the Soviet Union. What he said, which I thought was absolutely fascinating,…

It isn't actually all that scary; humans cope pretty well over a wide variety of temperatures. If the change caught everyone by surprise it'd be a huge problem but it seems to be fairly well understood and there is lots of time to adjust. Worst case scenario seems to be that people will stop migrating to Europe.

Europe is one of the world's largest agricultural producers and exporters. France alone is one of the top grain exporters globally. The EU exports massive quantities of wheat, barley, dairy, and processed food to North Africa, the Middle East, and Sub-Saharan Africa. Countries like Egypt, Algeria, and Nigeria are heavily dependent on European grain imports. An AMOC collapse would devastate growing seasons, slash yields, and potentially make large parts of Northern Europe unsuitable for current agriculture.

And it's not just food. Europe is a major producer and exporter of fertilizers. If European industrial and agricultural output collapses, the ripple effects hit global food supply chains hard. Countries that depend on those imports will face famine.

Then there's the knock-on, hundreds of millions of people in food-insecure regions losing a key supply source, simultaneous disruption to Atlantic weather patterns affecting rainfall in West Africa and the Amazon, potential shifts in monsoon systems affecting South and East Asia. It's a cascading global food security crisis.

> lots of time to adjust

This assumes a gradual slowdown, but paleoclimate evidence suggests AMOC transitions can happen within a decade or even less. The idea that we'd just smoothly adapt to one of the most dramatic climate shifts in human civilization is not supported by what we know about how these systems behave.

Re: Bye Bye Humanity: The Potential AMOC Collapse

#70

Post by lelanthran »

danaris wrote: post #68
lelanthran wrote: post #65

Earlier quoted context omitted.

> It's entirely possible for prawns fished from the coast of Mozambique to simply...go extinct. So? That isn't an irreplaceable staple, is it? Those prawns can be replaced by food that is grown in other places that are viable, whether newly viable or always viable is irrelevant. > For areas with good arable land to be plunged into inhospitably cold temperatures, only for other areas with arable land to be made too ho…

> Those prawns can be replaced by food that is grown in other places that are viable, whether newly viable or always viable is irrelevant. But those prawns are gone. The people whose livelihood depended on them have lost that. The people for whom they were a staple have lost that, no matter how replaceable they may be. Sure, given time , we may be able to find replacements for the things we lose to this drastic clima…

> What you're positing—that as various areas of the planet warm and cool, there will be perfect balance in what arable land we lose and gain

I am not, and never did propose that. I am arguing that there is no model that I am aware of that predicts a such dramatic NET reduction in arable area that society collapses. If you know of such models, now would be a good time to make me one of the lucky 10k :-) The only ones I am aware of are those predicting specific collapse on specific populations, most of which are tiny, percentage-wise.

> What it looks like to me is that you are either handwaving the decades (or more!) of turmoil, hardship, and loss of life for people in the areas that will be most affected by this,

No, I am not. Respectfully, you appear to be ascribing intentions to my argument that I don't have. I quoted the bit I was responding to specifically!

>>> I can't help but think of all the historical societies that collapsed due to even mild pressure on the food supply.

To which my answer is that this is very unlikely - there will be turmoil, hardship and (some - they aren't going to all die) loss of life in the affected currently-arable areas, but society does not depend on any specific area being viable.

The largest societies live nowhere near their source of food. The impact is not the same as the quoted "historical societies" that collapsed when the arable land did, because our societies don't have the dependency of "living on or near arable land".

Will there be a negative impact on those people living in and around arable land? Sure. Are they a significant percentage of our societies? Nope. Single-digit percentage of the population is nowhere close enough to cause a societal collapse.

All of this to say that, what happened to historical societies happened because those societies were built in, on and around their basic nutrition requirements.

Our societies are not.

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