Health Physics published the paper by Kenneth Skrable, George Chabot, and Clayton French on January 8, 2022.
Titled “Derivation of equations and example calculations of the components of CO2,” their study used 13C and 14C data to find the upper limit of human CO2 in the atmosphere is 11.6%, which (as of 2020) is 48 ppm of the 415-ppm total.
Their maximum amount of 48 ppm is exactly what Berry (2021) predicted using IPCC’s (Intergovernmental Panel on Climate Change) natural carbon cycle data. Using IPCC’s data, Berry predicted the mean human contribution to atmospheric CO2 as of 2020 is 33 ppm (8%) with lower and upper limits of 24 ppm (6%) and 48 ppm (11.6%).
Skrable et al. (2022) is a remarkable, independent confirmation not only of Berry (2021) but also of Harde and Salby (2021), Salby and Harde (2021a), Salby and Harde (2021b) and many of their references, as well as IPCC’s data for its natural carbon cycle.
Skrable et al. (2022) write (with symbols translated to language),
These results negate claims that the CO2 increase since 1750 has been dominated by human CO2 emissions.
It is now clear that nature drives and controls the CO2 increase and there is no scientific basis to believe that human CO2 dominates the CO2 increase as the IPCC and all climate laws assume.