First, the paper concludes 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.”

The premise of this argument is incorrect and indicates a fundamental misunderstanding of the causal link between anthropogenic emissions and rising atmospheric CO2. The fact that atmospheric CO2 has been rising at only about half the rate of anthropogenic emissions establishes that the natural environment is a net carbon sink and has been actively opposing the rise for at least the last 60 y. Hence, we know that anthropogenic emissions, predominantly from fossil fuel combustion and land use change, involve more than sufficient carbon to entirely explain the post-industrial rise (Canadell et al. 2021). //

Hence, even though individual CO2 molecules coming from fossil fuel emissions will cycle out of the atmosphere on a timescale of a few years, anthropogenic emissions have led to an enhancement in atmospheric CO2 that will have an adjustment timescale of a century or more. As many detailed carbon cycle studies have shown, anthropogenic emissions certainly are the cause of the increase in atmospheric CO2, and there are multiple lines of evidence that support this conclusion1 (Prentice et al. 2001). Also, the adjustment timescale is a century or longer, meaning that this enhancement in atmospheric CO2 will persist for a very long time (Ciais et al. 2013). //

Second, throughout the paper the authors have (1) failed to cite numerous related and relevant earlier publications in this field and (2) demonstrated a lack of fundamental understanding of biogeochemical carbon cycle processes. For example: ///

Thus, what has already been emitted will take centuries to stabilize, therefore it is too late to repair the damage and the best we can do is be prepared to mitigate the effects, notably by securing inexpensive inexhaustible energy sources.