The evolution of nuclear-perturbed CO2 is used to determine the removal time of atmospheric CO2. The exponential decline of anomalous CO2 establishes that absorption of CO2 is determined, not by extraneous reservoirs of carbon, but autonomously by the atmosphere.
Specifically, the rate at which CO2 is absorbed from the atmosphere is directly proportional to the instantaneous abundance of CO2 in the atmosphere. It operates with a single time scale, which reflects the collective absorption by all sinks of CO2 at the Earth’s surface. The long-term decline of anomalous CO2 reveals an effective absorption time of about 10 years.
The accompanying removal of atmospheric CO2 is much faster than has been presumed to interpret observed changes. Jointly with the Conservation Law governing atmospheric CO2, that absorption time is shown to reproduce the observed evolution of CO2, inclusive of its annual cycle. The latter treatment provides an upper bound on the absorption time, independent of but consistent with the value revealed by the decline of anomalous CO2. Together, the two determinations of absorption provide an upper bound on the anthropogenic perturbation of atmospheric CO2.
Continue reading: What Controls the Atmospheric CO2 Level? By Hermann Harde and Murry L. Salby.