The present Covid-19 lockdown provides an ideal opportunity to test one of the fundamental assumptions of the anthropogenic climate change theory by observing its effects on atmospheric CO2 concentration. It is an accidental experiment. If accepted theory of the global carbon cycle is correct, the change in human-caused CO2 emissions shown in the diagram above should be observable in the month by month rate of change of CO2 concentration in the atmosphere.
It is not observable!
Graphs a and b above show no significant variation in monthly differences for the first 5 months of 2020. The negative value in a is the difference between December 2019 and January 2020, i.e. before the lockdown.
Le Quéré, C., Jackson, R.B., Jones, M.W. et al. Temporary reduction in daily global CO2 emissions during the COVID-19 forced confinement. Nat. Clim. Chang. (2020). https://doi.org/10.1038/s41558-020-0797-x