Emissions and CO2 Concentration: An Evidence Based Approach
Posted on March 24, 2023 by curryja
by Joachim Dengler and John Reid
A new way of looking at the the atmospheric carbon budget.
Climate science is usually concerned about the question “How much CO2 remains in the atmosphere?”, given the anthropogenic emissions and the limited capability of oceans and biosphere to absorb the surplus CO2 concentration. This has led to conclusions of the kind that a certain increasing part of anthropogenic emissions will remain in the atmosphere forever. The frequently used notion of “airborne fraction”, which is the part of anthropogenic emissions remaining in the atmosphere, seems to suggest this.
We change the focus of attention by posing the logically equivalent question “How much CO2 does not remain in the atmosphere?”. Why is this so different? The amount of CO2 that does not remain in the atmosphere can be calculated from direct measurements. We do not have to discuss each absorption mechanism from the atmosphere into oceans or plants. From the known global concentration changes and the known global emissions, we have a good estimate of the sum of actual yearly absorptions. These are related to the CO2 concentration, motivating the guiding hypothesis for a linear model of absorption. It turns out that we do not need to know the actual coefficients of the individual absorption mechanisms—it is sufficient to assume their linear dependence on the current CO2 concentration.
This is a short summary of a recently published paper, where all statements expressed here are derived in detail and backed up with references and a mathematical model.
https://judithcurry.com/2023/03/24/emissions-and-co2-concentration-an-evidence-based-approach/#more-29903
