New Study Casts Doubt On The Accuracy And Reliability Of The Modern And Paleo CO2 Record

Reconstructed ice core CO2 values and modern CO2 and CH4 measurements do not support the narrative that human emissions are driving changes in atmospheric greenhouse gas concentrations.

New research extensively reviews the “pitfalls” of believing the conventional wisdom about modern CO2 concentration variations, as well as the “flaws” in reconstructed CO2 values from ice cores.

The record of annual increases (or decreases) in CO2 (ΔCO2) from the NOAA database indicate that prior to 1958 there were years when CO2 increased by 4 or 5 ppm from one year to the next, or even decreased by 3.5 ppm relative to the previous year.

 “[B]efore 1958 there are several years which show an increase of about 5 ppm or a decrease of about 3.5 ppm. … If these reconstructed values are correct, then there have been many years since the Industrial Revolution in which atmospheric CO2 has decreased.”

Problematically for the anthropogenic global warming narrative, it is not possible for human CO2 emissions to have driven either the 4.9 ppm increase from 1872 (286.66 ppm) to 1873 (291.56 ppm), or the 3.5 ppm decrease from 1908 to 1909. Year-to-year changes in human emissions could not have been nearly large enough to produce that much change – in either direction.

“The most impressive value is the of 4.9 ppm in 1873.”

“The year when human emissions exceeded 7.8 gigatons (Gt, equivalent to 1 ppm) was 1913. Before this year, an increase of more than 1 ppm per year is impossible, even when the CO2 increase over the Industrial Era is assumed to be of anthropogenic origin.”

Image Source: Ato, 2025

The NOAA record of year-to-year change in the methane (CH4) concentration reveals a similar problem, but this time in the 1980s-to-present data.

Not only are human CH4 emissions not large enough to account for the annual changes, but the changes show a nearly 40-year declining trend, 1984 to 2013, before rising again in the last decade.

“Since atmospheric methane has actually dropped even in present days, when humans are emitting large amounts of the gas [CH4], it cannot be assumed that about 1000 ppb [parts per billion] would have accumulated and risen in previous periods of low emissions.”

Image Source: Ato, 2025

There are fatal flaws in assuming we can actually derive accurate estimates of past global atmospheric CO2 concentrations from ice bubbles located at one site on Earth, Antarctica.

The author succinctly summarizes the problems with believing air from hundreds of thousands of years ago is fully sealed, uncontaminated, and never-changing in bubbles within the ice, and at no time in any and all excavation processes does the globally-representative CO2 value fail to deliver the precise measurement.

“There is no experimental evidence to prove the basic assumption of this method [that assumes the ‘composition of the gas at the time of capture will remain the same indefinitely’], that the gases in the upper layers will mix together for several years to thousands of years, and once they are sealed off, they will remain constant and no changes will occur.”

Image Source: Ato, 2025