> People are directly responsible for ~1/4th of all carbon dioxide in the atmosphere which is not exactly a minor change. That huge change in CO2 is not a hug

> People are directly responsible for ~1/4th of all carbon dioxide in the atmosphere which is not exactly a minor change. That huge change in CO2 is not a huge change in the atmosphere's ability to retain energy because (a) CO2 concentrations are fairly low and (b) other gasses have a much larger effect. Note that the atmosphere's ability to retain energy is not dependent on where the CO2 comes from.... I mention that because the earth has had much higher CO2 concetrations.