Brian's analysis is spot on. It reassures me that his other work is well thought out and encourages me to be a paid up member of this site. Rational US citizens are hard to find in the Trumponomic era.
Great article. I was working on the assumption that the Supreme Court Mass v EPA 2007 decision was the impetus and legal framework for Obama and his team to claim the CO2 was one of the greenhouse gases and that under the clean air act they are considered air pollutants and have an effect on human health. Am I off base. Thank you.
Hi Bart - You might be misinterpreting this paper, which was a cover article in Nature, and was well received by the climate science community. This study actually reinforces that fossil fuels cause atmospheric CO₂ increases. It shows rivers release ancient carbon from soils/rocks, meaning plants must absorb more atmospheric CO₂ than previously thought to balance this. The paper doesn't challenge fossil fuel emissions — it reveals nature works harder to combat them.
Note that the study points out that these emissions from natural sources also lack 13C and 14C which is the signature that is claimed be indicative of anthropogenic sourced CO2.
The paper does not say that CO₂ from rivers lacks 13C and 14C. It finds that river CO₂ is a mix of sources: some very old and depleted in 14C (and likely 13C), but a significant portion is from much younger, recent carbon as well. The results actually show a broad range of radiocarbon 14C values in river emissions, with most samples having less 14C than modern atmospheric CO₂, but not zero. Only petrogenic carbon is truly void of 14C, and it represents a small fraction — most river CO₂ comes from millennium-aged soil carbon and decadal carbon, both of which retain 13C and 14C, just less than the modern atmosphere.
(Also note that CO₂ from fossil fuels does contain a small amount of 13C, just no 14C.)
You are correct that "depleted" is the correct terminology here. The study claims to "provide evidence for a previously unrecognized, planetary-scale release of old, pre-industrial-aged carbon" *AND* these emissions match the isotopic signature of anthropogenic CO2. That presents a challenge to the the claim that the recent rise in CO2 is almost entirely anthropogenic. The authors also acknowledge that they don’t know if the increase in old carbon emissions is from natural variability or anthropogenic.
"Regardless, our analysis indicates that river CO2 emissions are responsive to inputs from old carbon sources and could increase under direct anthropogenic disturbance regimes such as landscape drainage, clearance, burning and agricultural soil cultivation, as well as because of anthropogenic climate change."
Brian's analysis is spot on. It reassures me that his other work is well thought out and encourages me to be a paid up member of this site. Rational US citizens are hard to find in the Trumponomic era.
Thank you!
Great article. I was working on the assumption that the Supreme Court Mass v EPA 2007 decision was the impetus and legal framework for Obama and his team to claim the CO2 was one of the greenhouse gases and that under the clean air act they are considered air pollutants and have an effect on human health. Am I off base. Thank you.
This recent study in Nature shows that the isotopic signatures attributed to anthropogenic origins also comes from natural sources:
https://www.nature.com/articles/s41586-025-09023-w
Hi Bart - You might be misinterpreting this paper, which was a cover article in Nature, and was well received by the climate science community. This study actually reinforces that fossil fuels cause atmospheric CO₂ increases. It shows rivers release ancient carbon from soils/rocks, meaning plants must absorb more atmospheric CO₂ than previously thought to balance this. The paper doesn't challenge fossil fuel emissions — it reveals nature works harder to combat them.
Note that the study points out that these emissions from natural sources also lack 13C and 14C which is the signature that is claimed be indicative of anthropogenic sourced CO2.
The paper does not say that CO₂ from rivers lacks 13C and 14C. It finds that river CO₂ is a mix of sources: some very old and depleted in 14C (and likely 13C), but a significant portion is from much younger, recent carbon as well. The results actually show a broad range of radiocarbon 14C values in river emissions, with most samples having less 14C than modern atmospheric CO₂, but not zero. Only petrogenic carbon is truly void of 14C, and it represents a small fraction — most river CO₂ comes from millennium-aged soil carbon and decadal carbon, both of which retain 13C and 14C, just less than the modern atmosphere.
(Also note that CO₂ from fossil fuels does contain a small amount of 13C, just no 14C.)
You are correct that "depleted" is the correct terminology here. The study claims to "provide evidence for a previously unrecognized, planetary-scale release of old, pre-industrial-aged carbon" *AND* these emissions match the isotopic signature of anthropogenic CO2. That presents a challenge to the the claim that the recent rise in CO2 is almost entirely anthropogenic. The authors also acknowledge that they don’t know if the increase in old carbon emissions is from natural variability or anthropogenic.
"Regardless, our analysis indicates that river CO2 emissions are responsive to inputs from old carbon sources and could increase under direct anthropogenic disturbance regimes such as landscape drainage, clearance, burning and agricultural soil cultivation, as well as because of anthropogenic climate change."
Does that mean you can go back to sleep Bart??