Health Physics published the paper by Kenneth Skrable, George Chabot, and Clayton French on January 8, 2022:
World Atmospheric CO2, Its 14C Specific Activity, Non-fossil Component, Anthropogenic Fossil Component, and Emissions (1750–2018)
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.
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.
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%).
You may discuss Skrable et al. (2022) here after you open the link above and read it.
To help you read their paper, Skrable et al. provided the separate summary below.
Derivation of equations and example calculations of the components of CO2
by Kenneth Skrable, George Chabot, and Clayton French
January 8, 2022
PS: To my knowledge, my book Climate Miracle is the only popular climate book that shows why natural CO2, not human CO2, controls the measured increase in atmospheric CO2.