I cannot get to the site, but:

At 3C ? Probably and maybe more, but it is hard to know. But I think we are headed to 4C with the way things are playing out.

But there is one variable, Nuclear War. I expect that will happen as the climate gets worse and worse. That war could drop us into a cold streak. After that ? Everyone gone ?

This book could give us a kind of a preview into what we are headed for. But in your mind replace nitrogen with CO2

https://www.goodreads.com/book/show/1189676.The_Nitrogen_Fix