At an atmospheric concentration of 380ppm and higher the limited long-wave spectral absorption of CO2 is essentially saturated. Consequently, yet more atmospheric CO2 becomes vanishingly less relevant to a greenhouse effect (if at all). And when more atmospheric water vapor is objectively evaluated its net-effect is found to be a negative-feedback rather than a positive one (in direct contradiction to the presumption of the Models). However, enhanced atmospheric CO2 clearly stimulates the proliferation of all forms of life. You might best call it Vitamin C…(O2).
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