World Atmospheric CO2, Its 14C Specific Activity, Non-fossil Component, Anthropogenic Fossil Component, and Emissions (1750-2018)

After 1750 and the onset of the industrial revolution, the anthropogenic fossil component and the non-fossil component in the total atmospheric CO2 concentration, C(t), began to increase. Despite the lack of knowledge of these two components, claims that all or most of the increase in C(t) since 1800 has been due to the anthropogenic fossil component have continued since they began in 1960 with Keeling Curve: Increase in CO2 from burning fossil fuel. Data and plots of annual anthropogenic fossil CO2 emissions and concentrations, C(t), published by the Energy Information Administration, are expanded in this paper. Additions include annual mean values in 1750 through 2018 of the C-14 specific activity, concentrations of the two components, and their changes from values in 1750. The specific activity of C-14 in the atmosphere gets reduced by a dilution effect when fossil CO2, which is devoid of C-14, enters the atmosphere. We have used the results of this effect to quantify the two components. All results covering the period from 1750 through 2018 are listed in a table and plotted in figures.These results negate claims that the increase in C(t) since 1800 has been dominated by the increase of the anthropogenic fossil component. We determined that in 2018, atmospheric anthropogenic fossil CO2 represented 23% of the total emissions since 1750 with the remaining 77% in the exchange reservoirs. Our results show that the percentage of the total CO2 due to the use of fossil fuels from 1750 to 2018 increased from 0% in 1750 to 12% in 2018, much too low to be the cause of global warming.

Automated summary

After the Industrial Revolution, the increase in atmospheric CO2 levels due to fossil fuel burning has been a major concern. However, research shows that the increase in CO2 since 1800 is not solely caused by anthropogenic fossil components, and the role of exchange reservoirs should not be overlooked.