Yep. Never disputed that. But not everything we emit increases the atmospheric CO2 concentration. Only like 50% of what we emit ends up in the atmosphere.Only problem is that we see a different carbon isotope signature in the atmospheric CO2. We see an increase in 12-C vs 13-C, indicative of burning of vegetal and fossil fuels. Plants fix lighter carbon. Same thing was being seen in terms of 14-C before we started doing atmospheric testing of nukes. So we KNOW where this new carbon is coming from.