I hear 1.5 C, 2 C all the time, but not much is happening [1] so I am looking for a best estimate to what should I expect in 2030, 2040 and 2050; not that 1.5 is "technicaly possible" cause it's practically impossible.
[1] https://www.nationalobserver.com/2018/12/12/analysis/co2-vs-...
Today’s models predict 1.5°-2.0° C by 2040, and 4° C by 2100 if no additional climate mitigations (not even promised or pledged) are implemented. The 4° C scenario is generally regarded as unrealistic so most climate models have another prediction which accounts for some additional climate mitigation which most countries have promised and pledged and put the increase at 2°-3° in 2100.
Why? It sounds like you might mean that, by about +2 °C (~double today's avg warming) we start to notice the impacts a little too acutely and take more action, am I reading that right?
That said, I'm under no disillusion that 2° C warming is not a horror scenario and that if governments actually cared about human lives they would limit warming to 1.5° I know they don't and the won't
> It is not unreasonable to assume that governments will follow through with at least some of their promises and pledges
FWIW, it actually looks like we're on a path to 2.5-2.9 °C of warming with current policies, and nearly another 1°C reduction with current pledges which are indeed much less likely to fully materialise. Via https://en.wikipedia.org/wiki/Climate_change#/media/File:Gre... which appears to use 2021 data. The "no climate policies" scenario is shown as having the lower error margin actually above +4°C
This is true, I actually used 2° C as a shorthand for 2° C - 3° C. I shouldn’t have done that. I actually believe we are more likely to be closer to 3° C at the end of this century than 2° C.
