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Fact brief - Does manmade CO2 have any detectable fingerprint?
Posted on 14 September 2024 by John Mason, Guest Author
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Does manmade CO2 have any detectable fingerprint?
Atmospheric chemistry shows that humans are driving the recent CO2 increase.
A key piece of evidence involves carbon isotope ratios in the atmosphere. Isotopes are different versions of the same element. Carbon comes in three isotopes of different weights and amounts: carbon-12 (98.9% of all carbon), carbon-13 (1.1%) and carbon-14 (trace amounts only).
Photosynthetic plants prefer the lightest isotope, carbon-12, because it is favored in photosynthesis reactions. That means plant tissues have relatively less carbon-13 than carbon-12. Fossil fuels, made of dead plants, also carry that distinct low carbon-13 isotope ratio, as does the CO2 produced by burning them.
Measurements over recent decades show a shift in the isotope ratio of atmospheric CO2, consistent with our burning of large amounts of ancient plant-derived carbon - in other words, fossil fuels. Natural carbon sources, like volcanoes, cannot explain this “fingerprint”.
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Sources
National Oceanic and Atmospheric Administration Stable Carbon and the Carbon Cycle
Global Biogeochemical Cycles Changes to Carbon Isotopes in Atmospheric CO2 Over the Industrial Era and Into the Future
National Oceanic and Atmospheric Administration How do we know the build-up of carbon dioxide in the atmosphere is caused by humans?
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Please comment on the following paper "World Atmospheric CO2, Its 14C Specific Activity, Non-fossil Component, Anthropogenic Fossil Component, and Emissions (1750–2018)" concluding "We determined that in 2018, atmospheric anthropogenic fossil CO2 represented 23% of the total emissions since 1750 with the remaining 77% in the exchange reservoirs. Our results show 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." Fact or fiction?
Rkcannon @1 :-
you mention a 2022 paper published in "Health Physics" by authors Skrable, Chabot, et al.
I gather that the journal "Health Physics" is primarily concerned with the topic of radioactivity effects on human health.
Presumably the Skrable paper had been rejected by reputable journals that normally published general scientific matters (including the physics of climate science).
Judging by Skrable's Abstract, the authors have made a colossal fundamental error in their understanding of the carbon cycle (involving the movement of CO2 into and out of Earth's atmosphere). And hence their conclusion is grossly erroneous.
The puzzle is : how did the journal Editor fail to see this error.
Rkcannon:
The paper in question, by Skrable et al, was discussed shortly after it appeared, over at AndThenTheresPhysics.
Note that the ATTP blog mentions a total of five rebuttal comments that were submitted to the journal.
Executive summary: the paper is a piece of junk.