Comment by wyre

Here is the IPPC's glossary so we can actually work with their defined terms: https://www.ipcc.ch/site/assets/uploads/sites/2/2022/06/SR15...

Greenhouse gas refers to any type of gas that makes up our atmosphere. Air pollution are substances entering the atmosphere that degrade air quality and human health.

Therefore air pollution is always going to be a greenhouse gas, but not every greenhouse gas is going to be air pollution.

CO2 is the principle man-made GHG that all the others are compared against. CO2 is what the IPCC refers to as long-lived climate forcer, which are gases that have a warming effect on the scale of decades, fitting the definition of air pollution.

CO2 is a pollutant and has been for as long as humans have been pumping out tons of it into the atmosphere.