claim: The minute increase of anthropogenic CO2 in the atmosphere ( 0.008% ) was not the cause of the warming—it was a continuation of natural cycles that occurred over the past 500 years.
evidence: Human activities since the beginning of the Industrial Revolution ( around 1750 ) have produced a 45% increase in the atmospheric concentration of carbon dioxide, from 280 ppm in 1750 to 415 ppm in 2019.