I think the reality is much more grim. I believe we are now firmly in the territory where it is incontestable. (My opinion was cemented after reading Overshoot: How the World Surrendered to Climate Breakdown by Andreas Malm, Wim Carton)

We will be spending much of our upcoming years trying to get people and capital to accept that fact, before we can even start thinking about what little we can even do. By which point, we may actually just be having to scramble to mitigate the immediate sequelae of the changed climate, rather than focus our efforts to fix the underlying cause.

Sad to say, with AI, crypto mining and now Trump/GOP, it is already too late.

Depending upon timing, if the AOC shuts down, Europe may not be a bad place to live. I am not sure how the AOC will impact NE US and Eastern Canada. But between the 40th parallels could be borderline uninhabitable for humans.

Way things look now, we seem to heading straight to +3C and maybe even +4C.

We burned fossil fuels because they were the cheapest form of energy. We will stop doing that when it becomes too expensive.

We are moving that direction, but a lot of damage will be done before we get there.

People don’t need to coordinate to ignore externalities

This is incorrect. There’s no evidence global CO2 levels and average temperatures have ever increased this fast outside of mass extinctions. On the other hand, there is plenty of evidence we’ve caused the current conditions.

Studies of ratios of carbon isotopes in the atmosphere show that there has been a relative increase in carbon-12 and a relative decrease in carbon-13 and carbon-14 consistent with the burning of fossil fuels, which contains no carbon-14 due to radioactive decay and low levels of carbon-13 because plants preferentially fix carbon-12. Research the Suess effect for more information.

We’ve known since John Tyndall’s research in 1859 that CO2 is a greenhouse gas. Besides countless other studies since, we also have satellite evidence that the Earth is reemitting less infrared radiation at the exact wavelengths that CO2 absorbs. CO2 as the driver of a greenhouse effect is not in doubt either.

There is also plenty of observational evidence that the oceans now trap more heat, that nights are warming faster than days, that winters are warming faster than summers, and these are all consistent with models of anthropogenic climate change.

Tough to tell exactly what you’re referencing, but you might be thinking about the Paleocene–Eocene thermal maximum, which was a natural increase in carbon in the atmosphere that led to higher temperatures. So, in some ways very similar to what we’re seeing now, but if my understanding is correct, even the PETM which was “dramatic” on a geological timescale took thousands of years to ramp up, and played out over 200,000 years. What we’re seeing now is happening much quicker, and is highly correlated with human influence.

> preparing for the outcome

How exactly do you propose to prepare for Europe becoming uninhabitable?

Wheres the research that shows this has happened before at the same timescale?

Citation needed