> The Cretaceous was a thing. The atmosphere had about as much CO2 as it could hold. There were lots of animals. We're headed back to it.
Extinction scale events have been "a thing" in Earth's history for as long as Earth's been around [0], as you note we are very likely in the middle of another one right now [1]
The big difference this time being: Previous ones most certainly had not been man-made, this one has a very high chance of being man-made.
Who's to say humanity is incapable of damaging Earths biosphere beyond a point where it can recover?
If we can manage to fill the oceans with more plastic than fish by 2050, then I'm certain we can manage to do quite a bit of damage to this planet as a whole [2].
A while ago I read a paper reasoning something like that might be the explanation for the Fermi paradox; extraterrestrial civilizations getting so advanced that they destroy the biosphere of their own planet, beyond repair, but not advanced enough to escape said destroyed planet. Sadly I can't find it anymore.
Wasn't that Great Filter even tho it might qualify as a Great Filter, I managed to find the paper [0], it's about applying the "Principle of Mediocrity".
Extinction scale events have been "a thing" in Earth's history for as long as Earth's been around [0], as you note we are very likely in the middle of another one right now [1]
The big difference this time being: Previous ones most certainly had not been man-made, this one has a very high chance of being man-made. Who's to say humanity is incapable of damaging Earths biosphere beyond a point where it can recover? If we can manage to fill the oceans with more plastic than fish by 2050, then I'm certain we can manage to do quite a bit of damage to this planet as a whole [2].
A while ago I read a paper reasoning something like that might be the explanation for the Fermi paradox; extraterrestrial civilizations getting so advanced that they destroy the biosphere of their own planet, beyond repair, but not advanced enough to escape said destroyed planet. Sadly I can't find it anymore.
[0] https://en.wikipedia.org/wiki/Extinction_event#List_of_extin...
[1] http://www.theworldcounts.com/counters/degradation_and_destr...
[2] https://www.washingtonpost.com/news/morning-mix/wp/2016/01/2...