Bjørn Samset of the University of Oslo and his colleagues used four climate models, which cover a range of climate sensitivities, to see what would happen to the global average temperature if the short-lived greenhouse gases (methane, nitrous oxide etc) were kept at their current level, but CO2 emissions ceased once they have reached a level of 420 parts per million (ppm). (This is 15 ppm above the current level of 405 ppm, or just another five years of emissions at the current rate.)

The result was average warming of 1.35°C over the four models, above a late 19th century baseline. (It has been demonstrated that global average temperatures increase while CO2 is increasing, and then remain approximately constant until the end of the millennium despite zero further emissions.)

You know, when I was a kid, I kind of had this thought that maybe nobody was doing anything because there was nothing to be done. I was wrong on that, and it would still be unequivocally better the sooner we do this. But I wasn’t entirely wrong, and here we are. If we stopped yesterday, this shit would last into the next millennium!?

If nothing else, at least it made me very conscious of enjoying everything I had.