I'm not sure that this is the whole picture, though. There were really high levels of CO2 millions of years ago but the life at that time was adapted to it. Ris

I'm not sure that this is the whole picture, though. There were really high levels of CO2 millions of years ago but the life at that time was adapted to it. Rising CO2 and temperatures will cause ecological damage to life currently unsuitable for it (e.g. corral reefs) and also economic damage from things including rising sea levels.