4000 ppm CO2 was found in nature far before pre-industry came along. Does the fact that anything "happened in nature" make it "ideal?" What is the globally "ideal" level of CO2 anyway? Certainly 200ppm is an order of magnitude low when considering the ideal for plants.
4000 ppm CO2 was found in nature far before pre-industry came along. Does the fact that anything "happened in nature" make it "ideal?" What is the globally "ideal" level of CO2 anyway? Certainly 200ppm is an order of magnitude low when considering the ideal for plants.