New Study: CO2’s Atmospheric Residence Time 4 Years…Natural Sources Drive CO2 Concentration Changes

New Study: CO2’s Atmospheric Residence Time 4 Years…Natural Sources Drive CO2 Concentration Changes

“Clearly, the atmospheric CO2 observation data are not consistent with the climate narrative. Rather, they contradict it.”  – Koutsoyiannis, 2024

Per a new study, the Intergovernmental Panel on Climate Change (IPCC) utilizes “inappropriate assumption and speculation,” as well as non-real-world models of “imaginary data,” to claim CO2 emissions derived from fossil fuel burning function “weirdly,” far differently in the atmosphere than CO2 molecules derived from natural emissions (e.g., plant respiration, ocean outgassing) do.

“The ambiguity is accompanied by inappropriate assumptions and speculations, the weirdest of which is that the behavior of the CO2 in the atmosphere depends on its origin and that CO2 emitted by anthropogenic fossil fuel combustion has higher residence time than when naturally emitted.”

While the IPCC acknowledges emissions from natural sources have an atmospheric residence time of only 4 years, they have simultaneously constructed model outputs that assert CO2 molecules derived from fossil fuel emissions remain in the atmosphere for hundreds, thousands, tens of thousands, even several one hundred thousands of years.

Per the IPCC:

“15 to 40% of an emitted CO2 pulse [from anthropogenic emissions] will remain in the atmosphere longer than 1000 years, 10 to 25% will remain about ten thousand years, and the rest will be removed over several hundred thousand years.”

“Carbon dioxide (CO2) is an extreme example, its turnover time is only about 4 years because of the rapid exchange between the atmosphere and the ocean.”

Again, a four-year residence time for natural CO2, but hundreds of thousands of years residence time for CO2 molecules elicited from fossil fuel burning. It would seem just about any result can be derived from imaginary data.

Image Source: Koutsoyiannis, 2024

Instead of relying on models built on assumption and speculation, Dr. Koutsoyiannis utilizes a well-established, hydrology-based theoretical framework (refined reservoir routing, or RRR) combined with real-world CO2 observations to robustly conclude the residence time for all CO2 molecules, regardless of origin, is between 3.5 and 4 years.

The applied theoretical results match the empirical results so closely (e.g., an empirical mean of 3.91 years vs. a theoretical mean of 3.94 years at Barrow, and an identical 3.68 years for both empirical and theoretical means at Mauna Loa from 1958-2023) that the theoretical framework can be said to be “close to perfect.” In other words, the consistency of the applied calculation with real-world observations provides robust evidence that CO2 residence time is likely close to this range.

In contrast, the calculated probability for the modeled, imaginary-data-based claim that the residence time for a CO2 molecule persists for over 1000 years is 10⁻⁶⁸, which means the probability value is “no different from an impossibility.”

Image Source: Koutsoyiannis, 2024

A residence time of only 4 years for all CO2 molecules, regardless of origin, is consistent with the conclusion that nature is dominant in driving changes in CO2 concentration. Fossil fuel emissions serve only a minor role.

Since 1750, additions to the atmospheric CO2 concentration derived from natural emission sources associated with biological processes are about 4.5 times larger than the contribution from fossil fuel emissions (e.g., 22.9 ppm per year from nature, 5.2 ppm per year from fossil fuel combustion).

In other words, observed CO2 data contradict the climate narrative that says anthropogenic fossil fuel burning is driving CO2 concentration changes.

Image Source: Koutsoyiannis, 2024

43 responses to “New Study: CO2’s Atmospheric Residence Time 4 Years…Natural Sources Drive CO2 Concentration Changes”

  1. Ferdinand Engelbeen

    While I too would like to see a natural source for the recent increase of CO2 in the atmosphere, as that would destroy the whole “CAGW” meme, what Demetris Koutsoyiannis (and several before him) writes violates the carbon mass balance and several other observations thus can’t be true.

    Demetris largely confuses between residence time, that is the time that a single CO2 molecule (of whatever origin) resides in the atmosphere with the “adjustement” time, that is the time that an excess injection of CO2 (of whatever origin) above some dynamic equilibrium needs to be removed back to equilibrium. Two totally different concepts, but largely used as “residence time” in both cases, even by the IPCC…

    What is the (real) residence time of CO2 in the atmosphere?
    The formula for the residence time is quite simple:

    RT = mass / throughput
    or for 2020 figures:
    RT = 890 PgC / 215 PgC/year = 4.14 years

    Where 1 PgC = 1 GtC = 2.13 ppmv CO2

    The 215 PgC/year is mainly caused by the huge seasonal fluxes between oceans via the atmosphere into vegetation in spring/summer and reverse in fall/winter. At the end of the year, there is zero change of CO2 in the atmosphere, as long as the sum of all ins and outs is equal.
    These processes are temperature/photosynthesis/biological and only partly influenced by the momentary CO2 pressure in the atmosphere.

    Then we have the adjustment time.
    If the removal of some extra constituent of a dynamic process in equilibrium is linear with the disturbance (Le Chatelier’s principle), then the formula to reduce an extra injection of that constituent to 1/e (~37%) of the original disturbance also is quite simple:

    Tau = disturbance / effect
    or again for 2020:
    Tau = 120 ppmv / 2.25 ppmv/year = 53 years

    Quite a difference with the residence time…
    The 2.25 ppmv/year is the real, calculated, net removal rate of CO2 out of the atmosphere: observed increase in the atmosphere (Mauna Loa: ~2.25 ppmv/year) minus human emissions (calculated form fossil fuel sales and burning efficiency: ~5 ppmv/year).
    That means that nature over the past 6 decades was near always a net sink for CO2 of ~2.25 ppmv/year, not a source…

    See further for an in-depth analyses:
    http://www.ferdinand-engelbeen.be/klimaat/co2_origin.html

Share: