siehe dazu auch zur Studie des US-Wissenschaftlers Daniel H. Rothman
"Over recent years, concern about a coming hothouse mass extinction set off by human carbon emissions has been on the rise. Studies of Earth’s deep history reveal that at least 4 out of the 5 major mass extinctions occurred during both hothouse periods and during times when atmospheric and oceanic carbon spiked to much higher than normal ranges. Now a new scientific study reveals that we have already emitted 50 percent of the carbon needed to set off such a major global catastrophe."
https://robertscribbler.com/2017/09/22/half-way-to-catastrophe-sixth-global-mass-extinction-to-be-triggered-by-or-before-2100-without-rapid-emissions-cuts/