claim: Human additions of CO2 are in the margin of error of current measurements and the gradual increase in CO2 is mainly from oceans degassing as the planet slowly emerges from the last ice age.
evidence: Human beings are now dramatically changing our planet and altering the environment by modifying the global carbon cycle through anthropogenic carbon dioxide (CO2) emissions from the burning of fossil fuels. The CO2 concentration of air was around 280 ppm in 1750 AD (the beginning of Industrial Revolution), but it has increased over the last two centuries and is currently above 400 ppm. Carbon dioxide is one of the primary greenhouse gases in Earth’s atmosphere, together with water vapor, methane, nitrous oxide, and others. The Intergovernmental Panel on Climate Change (IPCC) intermediate RCP 6.0 scenarios (IPCC 2013b) predicts that the CO2 concentration in air will increase to 720–1000 ppm by 2100 AD and that the global mean temperature will rise by 2.6 °C. Comparison of CO2 concentrations in the atmosphere with fossil-fuel burning data indicates that about 60% of fossil-fuel emissions remain in the air. The remainder is mainly absorbed by the ocean, which may provide some relief from severe warming.