Graph of the Week Number 2
See new posts
Conversation
Peter Clack
The red line for plant death on earth is around 150 ppm, implying a critical lower limit for CO₂ concentrations below which life would struggle to survive. The optimum CO₂ level for photosynthetic plants & algae is around 1,000 ppm, which last occurred when the first primates arose. Since then, CO₂ levels have been steadily declining. Yet it is still significantly higher than today's 400 ppm, after recovering from a low point of 180 ppm during the glacial optimum 26,000-20,000 years ago. CO₂ has been trending downwards from 2,750 ppm 160 million years ago, when a coral diversity explosion occurred & when CO₂ levels were significantly higher. This downplays claims that higher CO₂ levels will damage coral reefs.
https://x.com/PeterDClack/status/1967400909484466473