From a purely logical perspective, humans can only be the main cause of the ongoing warming if two preconditions are met: CO2 must have a strong climate impact and the large amount of CO2 in the atmosphere must primarily be anthropogenic. However, the fulfillment of both preconditions is scientifically controversial.
Controversy regarding the strength of the climate impact of CO2 stems primarily from this being a quantitative question with many uncertain assumptions that everyone makes differently. This leads to results and consequences ranging from “harmlessly small” to “catastrophically large”. A resolution of this dissent is not in sight.
Controversy regarding the primary origin of CO2 is less about quantitative aspects but more about the fundamental assessment of the behavior of CO2.
In this paper, an assessment of the behavior of CO2 is made, based on elementary physical quantities and principles. Different viewpoints are taken into consideration, but results stay the same: The increase in atmospheric CO2 is most likely predominantly due to increased emissions from natural sources with only a minor contribution from anthropogenic emissions. The popular thesis “It’s all man-made” is challenged and a careful review is urgently required.If the predominantly natural origin of the large amount of CO2 is confirmed, then there are logically only two possibilities left: Either climate is primarily dependent on CO2, then it is primarily dependent on natural CO2. Or, other climate influences predominate, then CO2 only plays a minor role, regardless of its origin. In both cases, nature is stronger than man and it makes no sense to reduce or even stop anthropogenic CO2 emissions for climate protection reasons! We could concentrate on more urgent tasks. That is why the question of the origin of all the CO2 is so important. The intention of this paper is to contribute to an in-depth discussion.
The paper can be read here: Climate: Man, or Nature? A Contribution to the Discussion by Eike Roth.