Chat lines by Doitsujin

Well, in very long term, we're probably doing something beneficial because we're certainly delaying the next ice age. The downside is we're making the planet warmer than it hasn't been for millions of years. And in a rapid, very short amount of time which

Geologists are still discussing wether or not the entire earth actually froze over in that period right up to the equator, or not.

something similar happened "shortly" before the end of the precambrian, during a period that is aptly named "Cryogenian".

Earth's first ice age back in the precambrian probably was caused because the first photosynthetic lifeforms sieved too much carbon dioxide out of the atmosphere, which caused the temperatures to crash.

Well, sometimes things also went awry.