The climate during the Holocene

Over the last 8,000 years, the atmospheric CO₂ concentration has risen steadily, while the average global temperature has declined. This fact contradicts the claim that CO₂ is the main "global warming" control knob.
CO₂ is a greenhouse gas but it's warming capability is almost saturated. Even at much lower concentrations it absorbs almost all energy that is emitted in it's absorption wavelength bands, so adding more CO₂ to the atmosphere has no measurable effect on global temperatures.

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