No one needs to be a climate scientist or even to have a college degree to download the CO2 data from the Mauna Loa lab, analyze it, and see for themselves that CO2 from human fossil fuel emissions is not detectable as a trend, an anomaly, or significant deviation in the trend of net atmospheric CO2 concentration observed at Mauna Loa. High school math is all that is needed.
No statistically significant anthropogenic CO2 trend is detected in the net global CO2 concentration trend, despite the input into that ongoing trend of gigatons of CO2 from fossil fuels estimated to have increased 15% per year. Since the fossil fuel contribution is too small to detect in the overall trend, we do not have data that might inform whether the anthropogenic fraction is so small that it is insignificant, lost in the noise of the massive flux of global CO2 emissions and absorptions by nature, or alternatively whether the carbon sinks, sources and balance are adjusting to the injection of gigatons CO2 emissions of fossil fuels, or some combination of these two alternatives.
But, it is obvious that human CO2 and CO2 from fossil fuels are not affecting climate.