The Last Time CO2 Was This High, Humans Didn't Exist
Sunday, May 5, 2013 - 13:00
in Earth & Climate
The last time there was this much carbon dioxide (CO2) in the Earth's atmosphere, modern humans didn't exist. Megatoothed sharks prowled the oceans, the world's seas were up to 100 feet higher than they are today, and the global average surface temperature was up to 11°F wa …