I never looked much into the details, but all I heard over and over was we need to keep under 2c rise from pre industrial levels and will go over in like 50 years if we don’t start to change now
I mean I’m not entirely sure why the 50 years part matters, it seems to me that 2 degrees is 2 degrees and it matters regardless of if it is 50 years or more. I’m guessing 2C is just some somewhat arbitrary threshold to have as a target.
2 C is the amount of warming that scientists and economists have somewhat agreed is the “reasonable” amount of heating that will occur if we start changing things right now. Above that and we start getting really bad climate feedback loops that could theoretically push temperatures to +5 C
As far as I know there isn’t much basis to 1) managing to keep it below 2C (which is considered unlikely by now) or 2) that 2C is particularly important anyways. Bad stuff will and does happen below 2C, and there isn’t that much evidence that says “x happens at 2C” afaik. Like, I’m pretty sure they picked it because it’s a round number. The answer to the question “how much should we limit climate change” is always “more than what we are doing” and the answer to “where’s the tipping point and does it exist?” tends to be “who the fuck knows, it’s probably somewhere upwards of now”. I’m not sure I like how some people are taking the tipping point stuff and running with it to argue that it’s pointless to do anything anyways.