Speculating on how much time we really have left - a climate change thread

Great Debates
1

Break out your crystal balls everyone. Let’s do some speculating:

Climate change is accelerating. All of the scientific evidence collected to date confirms this. Estimates vary, but increasingly look like we will surpass 3C of warming above the pre-industrial baseline this century.

Climate change itself is not an on/off switch for societal collapse but rather a risk multiplier. As the earth warms, the negative impacts will increase in both frequency and severity. Absent a collective intervention or miraculous scientific breakthrough, this must exceed the capacity of society to absorb these shocks at some point.

So the question is - when?

Personally, I look at things like the looming disaster in the western US this year (tldr: exceptionally warm winter has set up a water and wildfire crisis for this summer - right as a strong El Niño is forecasted to be ramping up), and I think to myself - this is what we’re experiencing with a mere 1.5C of warming.

So, true to my username… I’m not optimistic we’ll even make it as far as 3C before the wheels start to fall off. I think we should consider ourselves lucky if we make it out of the middle of the century with a functioning society.

2

People have predicted catastrophe from the weather often. Many quotes of “By so and so a year its all over.” All wrong.

3

Except that in this case, we are entering a climate regime that humanity has never experienced. What happened in the past is irrelevant.

For the same reason I can’t really give a prediction because I don’t know what will happen under a climate we can only speculate about.

4

It’s too late to prevent it from being catastrophic, because it’s been catastrophic for decades now. It’s not too late to prevent it from being even worse than it is, because no matter how long it takes, action sooner will be less bad than action later.

5

What do the weather models show? How far ahead can be predicted?

6

“Weather” is not the same as “climate”.

7

We haven’t experienced it, but that doesn’t mean we can’t make educated guesses based on our understanding of the interplay between all of these systems.

E.g. we don’t know exactly how much sea level rise to expect, but we can project out the current rate of SLR over time, and we know roughly how many people and how much infrastructure is at risk for any given level of rise.

8

There have been catastrophes, certainly, based on climate change, but so far not irrecoverable; that is, not beyond the capacity of society to absorb the shocks. That seems to be the OP’s criterion for disaster.

I think that’s the OP’s question, when will it be too late to prevent it from getting worse than it already is at that point? When the engines outside human control will take over and further damage will be inexorable.

9

That is what is so pernicious about this problem. We rely on experience (both personal and cultural) to understand risk.

99.99% of the time your answer is the correct one. But I don’t think it is this time because we are leaving behind the regime that we understood on an experiential level and entering a new one where all of our instincts built on “what’s gone before” simply no longer apply. We’ve sailed clear off the edge of the map into the area marked “here there be dragons”.

That doesn’t make us completely blind though. We still have eyes and can see to the edge of the horizon what it is we’re sailing towards even if what we’re sailing towards was never charted previously.

10

Which is limited. For example, we don’t know if the weather will be stable enough to allow for agriculture anymore, or how destructive things like hurricanes can get when enough energy is put into them, or how non-human factors will affect the rate and extent of climate change.

11

That’s certainly part of it. Everything I understand about climate science says there is a point past which we can no longer hope to rein things back in. And a part of me deep down worries we might have already reached that point.

The other part of the question would be what is our perceived capacity to keep weathering these shocks?

We might phrase it as “how many billions of dollars of damage” can global infrastructure endure before the modern world stops functioning. Similarly, “how many millions of people dead or displaced” before the population strain becomes too much?

The intersection of those two things, increasing disasters and the limits of shock absorption, would essentially be the answer to my question.

12

We can hope.

13

True, but even if we make the (hopefully) reasonable assumption that agriculture will still be possible and hurricanes won’t get that much more powerful - there must exist limits on our ability to deal with natural disasters as we currently understand them. How many acres of wildfire before the cost is too much to bear in California? How much flooding can Spain truly handle? Etc.

An economist might think of it in terms of what percentage of GDP can be devoted to disaster recovery before a country simply becomes financially insolvent and collapses.

14

How do you measure this, though? When do you say “yes, it’s here now”?

If you live in the West, the last decade has already been a visible escalator of natural disasters. If you lost your house in a wildfire, the crisis has already long since arrived. On the other hand, if you’re living in a climate-controlled apartment in a temperate climate, you might not have noticed much different at all.

Climate change even under the worst projections isn’t going to suddenly change the surface of the earth overnight the way that, say, nuclear war might. It will affect different parts of the world differently, not just based on geography but socioeconomics, and richer developed countries with proactive governments able to implement mitigations and who can afford cheap energy (fossil fuels, solar, etc.) are going to be better able to adapt than poorer, smaller, and island-bound countries.

Those who contribute the most to it (China and the US) will probably also see relatively mitigated impacts just because of the amount of money and land those two countries can throw around to deal with it, even though both are dragging their feet. Meanwhile places like the EU are doing a lot of mitigation efforts, both for their own residents and presumably for the inevitable refugees coming out of Asia, Africa, and the Middle East.

There is no one single answer. A few billion dollars isn’t much to any developed economy; that’s like a week in Iran. A few million deaths, as in COVID, is also not much in the grand scheme of things. You’d need to kill a hundred million people to impact the world population by 1%.

It’s not going to happen equally around the world but concentrated in pockets of high-volatility regions (both in terms of climate and geopolitics). I think my underlying point is that there isn’t a singular “we” here. Whether you mean “we” as in a specific country (like the US), the West, or people overall, the impacts will be highly variable from place to place and affecting individual regions and households quite differently. Elon Musk’s experience with climate change is going to be very different from yours or anyone else in the US or South Africa; people living in coastal, tornado, or wildfire prone areas are going to have a very different experience than those outside those belts, etc.

Sure, climate change is going to increase destabilization everywhere, but the world is already plenty unstable and has been that way for most of our species’s history. At the same time, power and wealth are also getting more and more concentrated in the hands of fewer and fewer people, which means that the average person matters less and less. As long as the elites can run keep running their little empires, frankly, a lot of us little people can suffer and die and not a whole lot will really matter — we’re mostly invisible except at times of revolution and terrorism.

So my answer: From the direct impacts of climate change alone, centuries or millennia or never. Life goes on as it always had, and the earth has had much more volatile climates than what we’re facing now.

But from the indirect impacts of panicked, desperate humans using violence to try to escape their predicaments? Maybe much shorter… two or three decades? But even then, it’s not going to affect the whole world the same. There’ll still be pockets of rich people living just fine while the rest suffer, just like it is now. It doesn’t really take much for society to descend into chaos and anarchy, but then back into ordered authoritarianism soon after that. Even if (or, really, when) countries fall, societies will re-emerge and hierarchies will re-form and life still goes on.

15

I more or less agree.

I don’t think we (i.e. the modern developed society that most of us are accustomed to) will survive to see the true extent of the direct impacts because the pressure on the structures we’ve created, to (mostly) coexist on this planet in (relative) prosperity, will cause a rupture well before then.

I also have thoughts on the likelihood of surviving a large portion of the globe sliding into chaos or the prospects for reordering afterwards, but mostly I’m wondering how long the current status quo can continue.

16

civilization survived far worse things than climate change. The black plague for example.

Take Russia from 1900 to 1950. They survived WW1, a civil war, the spanish flu, a second civil war, Stalins purges, the famines, and WW2. It wasn’t pleasant, but society survived.

It doesn’t take much to keep people alive. Basic food and basic medicine. There are ample parts of the world where staple crops like corn, potatoes, rice, wheat, etc that are high in calories per acre can still be grown. Agriculture will become less productive in central america, but it’ll become more productive in the Northern US and Canada for example. You need roughly 1 million calories per year to keep someone alive. Potatoes, corn, sugar, etc produce 15+ million calories per acre. There are about 12 billion acres of farmland on earth, and in an emergency situation we only need 500 million acres to feed all 8 billion people on earth.

Also keep in mind we know how to make butter out of coal. The nazis did this. In a survival situation we can make coal butter, and probably various other food products out of non-agricultural materials. We can grow vats of algae, fungi or bacteria and eat that.

By the year 2100 water levels are expected to rise about ~2 feet and temps will go up by about 3C. It’ll be tough, but it won’t end civilization. They’ve also had to change predictions about what the year 2100 will look like since renewables are growing faster than expected, so worst case scenarios are less likely.

Also keep in mind we’ve gone from renewables being a pipe dream to renewables being cheaper than coal in 20 years. We’ve downgraded from predictions of 4-5C temp growth by 2100 to ~3C temp growth due to how fast renewables grew.

I think some of you guys just like feeling sad, scared and defeated.

17

Again; we don’t know that, because humanity has never experienced this. Never. We are moving into a climate that has not existed for over 30 million years, and we have no idea what it will really be like. We don’t know what agriculture will be like, or where it will be better or worse, or if the new climate will be too chaotic for it to exist. We don’t know what the ongoing mass extinction will do to our ability to feed ourselves.

And frankly, I think the odds are that at some point we’ll destroy most of our civilization with one or more nuclear wars, so whatever we do we’ll be doing it with much worse in the way of knowledge, technology and resources.

18

Do you have a reference that? First I’ve heard that we’ve downgraded any estimates due to renewables. 2025 saw the most fossil fuel use ever. We’ve altered our energy mix some yes, but we’ve not put a dent in our actual emissions yet - they’re still increasing in line with the “business as usual” scenarios.

I think people that refuse to confront or consider the very real scenarios facing us are the scared ones. They tend to have reflexive reasons why this couldn’t possibly be as bad as it appears to be and anecdotes about how things were so much worse in the past than they could possibly be in the near future. Perhaps related, they rarely seem to understand the actual current state or where we seem to be headed.

For all that though, I still hope they’re right.

19

We’ve long since surpassed the point where any hope for reversal or saving the situation could have been done. From this point on, everything is going to be adaptive. We’ll implement measures to help cope with the bad climate, invent technology to mitigate the damage, but the damage is done.

It’s like living with a physical injury that is permanent. The time to avoid the car collision was before; now that you’ve already been hit by a car, you can only cope the best you can with your new wheelchair life.

20

That isn’t good news nor is it even remotely accurate. There was never a “prediction” of 4 to 5°C temperature rise by 2100 – that range is the worst case of all the modeled climate scenarios, namely RCP 8.5, which has always been considered to be very unlikely. But in order for climate change impacts to be anything close to manageable, we need to keep temperature rise to under 2°C by 2100, and it looks like we will miss that by a significant margin. 3°C is nowhere near good enough. It may not sound like much but regional changes will be far more extreme, including amplification of temperature rise and consequent feedbacks in the polar regions.

Saying that agriculture will become less productive in tropical regions is likely a severe understatement, because most of those regions are both economically and climatologically the most vulnerable to climate change and will face severe stresses on water and food supplies. Northerly migration of desperate refugees may become a serious problem.

And it’s not a given that agriculture will necessarily be more productive in the north. Yes, it will warmer on average, but climate change also brings with it unwanted regional changes like floods, droughts, and wildfires, along with northerly migration of damaging invasive species like is already happening with the pine park beetle. Let’s also not forget loss of land to rising sea levels and the impact of ocean acidification on marine life.