Shock Evidence Suggests Humans Are Not Responsible for Most of the Increase in Atmospheric CO2. By Chris Morrison

Humans contribute just 4% of the carbon dioxide that enters the Earth's atmosphere each year but the 'settled' science of anthropogenic climate change states that this has caused a 50% rise in the trace gas since pre-industrial times. In fact, this arguable statement can be tested using carbon isotope data and the results are in from a detailed mathematical paper just published by a leading climate scientist (sceptic branch) Dr Willie Soon. His bombshell conclusion is that fossil fuels are not responsible for the recent increase in atmospheric CO₂. This is despite the widespread scientific conclusion to the contrary that has the added advantage of backing the political Net Zero fantasy.

Needless to say, mainstream media and science will try to ignore this sensational finding from Dr Soon and his fellow author Jonathan Cohler. If it is true, or accepted as a reasonable proposition, it will destroy the main scientific basis for Net Zero. Although atmospheric CO₂ remains at denuded levels compared to the past at around 425 parts per million, activists have latched onto the recent healthy rise at a time of a 1°C bounce back in global temperature from a mini ice age to spin politicised poppycock about fireball Earth.

Examining the different isotope signatures of CO₂ derived from fossil fuels and other forms of the gas released naturally into the atmosphere, the authors calculated that hydrocarbons could account for between zero and 26% of the recent increase.

The scientists also introduce a second piece of evidence to back up their finding. Five hundred years of growth layers on a Caribbean marine sponge show the various CO₂ isotope signatures remaining remarkably constant despite an enormous expansion in the use and burning of fossil fuels. From all this, the authors state that virtually all the recent increase in atmospheric CO₂ comes from natural sources, rather than the accumulation of fossil fuel emissions. The paper's central conclusion is that the contribution of fossil fuel use is effectively zero.

In simple terms, this is how they did the maths. Carbon comes in two main forms known as C-12 and C-13. The more abundant form C-12 is lighter and accounts for about 99% of the total. Naturally occurring carbon contains both isotopes, but the proportion of one to the other varies slightly depending on where the carbon came from. Scientists have agreed a standard known as VPDB against which carbon samples can be compared. Carbon from fossil fuels is relatively low in C-13 with a typical signature of minus-28. This means that the ratio of C-13 to C-12 is 2.8% lower than the standard. Naturally released CO₂ from the ocean and other sources are richer in C-13 with a signature of minus-8, or 0.8% lower than VPDB.

Soon and Cohler examined measurements of carbon isotopes from four atmospheric monitoring sites in Hawaii, Alaska, California and the South Pole, and used a mathematical technique known as the Keeling plot to estimate the isotope signature of the net addition of CO₂ to the atmosphere. The results was a value of approximately minus-13.2. The authors note that if fossil fuels were responsible for most of the net increase, the resulting isotopes signatures would be much closer to minus-28. Thus, they argue that fossil fuels cannot be responsible for most of the recent increase.

The Net Zero promoting opinion is that isotope evidence proves that humans are primarily responsible for increased atmospheric levels of CO₂, and by extension the rise has caused most if not all global warming for at least a century. This opinion is central to the 'settled' science of climate change. If the opinion is attacked and proved wrong in any significant way, the entire carefully constructed and curated propaganda around Net Zero collapses like a house of cards.

It is often assumed that the Earth's atmosphere has been in balance in the recent past. But there are huge CO₂ interactions, with both the oceans and the land releasing and capturing the gas. Volcanoes are also a large emitter of CO₂, perhaps more than was first thought since many underwater mountains remain undiscovered. In other words, a period of stable CO₂ atmospheric concentrations in the recent past does not prove that every source and sink was individually balanced. It just shows that the net effect was approximately balanced. And of course, the current levels of CO₂ were rarely found in the past. Levels were much higher in the past with plants benefiting from its nutrients. Over the last 600 million years of life on Earth, the average level of CO₂ in the atmosphere is seven times the near starvation level seen today.

In earlier work published in March last year by Soon and Cohler, it is noted that atmospheric CO₂ molecules are exchanged with natural reservoirs on a timescale of approximately 3.5-4 years. In this paper, which was a critical reassessment of the anthropogenic CO₂-global warming hypothesis, the authors interpret carbon isotope measurements as evidence that natural processes, rather than human emissions, dominate the recent increase in atmospheric CO₂. Due to this continual recycling and short atmospheric residency, the authors suggest that it calls into question how much of the observed recent atmospheric rise in CO₂ is attributable to human emissions.

Of course, questions are not allowed in polite climate politics and science, so the work of inconvenient questioning scientists such as Willie Soon and Jonathan Cohler will remain undebated and largely ignored in these captured Net Zero fantasising circles.

Chris Morrison is the Daily Sceptic's Environment Editor. Follow him on X. His new five-star customer rated book IMPLAUSIBLE: How scientists, activist politicians and journalists invented a climate crisis, weaponised junk computer model findings and claimed a fake consensus to promoter the collectivist Net Zero fantasy is out now on Amazon and only £3.99 for the download and £8.99 for the paperback.

https://dailysceptic.org/2026/11/10/shock-evidence-suggests-humans-are-not-responsible-for-most-of-the-increase-in-atmospheric-co2/