Carbon Dioxide
Number of papers: 23
Relative Potency of Greenhouse Molecules — Atmospheric and Ocean Physics, 2021; van Wijngaarden and Happer
This paper produced one of the most important graphs in climate science, be sure to read it:
Atmosphere and Greenhouse Gas Primer — Atmospheric and Oceanic Physics, 2023; W. A. van Wijngaarden & W. Happer
This “simple” paper presents the basics of radiative transfer via greenhouse molecules. It is understandable to people with a strong background in calculus, entropy, and matrix math. It explains in detail why the earth’s atmosphere has a lapse rate and gives a brief overview of the Schwarzchild equation. Highly recommended.
Climatic consequences of the process of saturation of radiation absorption in gases — Applications in Engineering Science, 2024; Kubicki et al.
Not well written but well researched. The bottom line: it’s not CO2. The IPCC and others got confused by Henry’s law and should reconsider their fundamental assumptions. Excellent paper.
World Atmospheric CO2, Its 14C Specific Activity, Non-fossil Component, Anthropogenic Fossil Component, and Emissions (1750–2018) — Health Physics, 2022; Skrable et al.
“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.”
Revisiting the greenhouse effect—a hydrological perspective — Hydrological Sciences Journal, 2023; Koutsoyiannis & Vournas
“As the formulae used for the greenhouse effect quantification were introduced 50-90 years ago, we examine whether these are still representative or not, based on eight sets of observations, distributed in time across a century. We conclude that the observed increase of the atmospheric CO2 concentration has not altered, in a discernible manner, the greenhouse effect, which remains dominated by the quantity of water vapour in the atmosphere, and that the original formulae used in hydrological practice remain valid. Hence, there is no need for adaptation due to increased CO2 concentration.”
Net Isotopic Signature of Atmospheric CO2 Sources and Sinks: No Change since the Little Ice Age — Sci, 2024; Demetris Koutsoyiannis
This is a follow-on to the paper above, which received more than 1,000 comments on Judith Curry’s blog. He revisits the calculations and claims that the CO2 in the atmosphere today, and the rise during the last 100 years or so, is natural and there is no “signature” from humans.
Laws of Physics Define the Insignificant Warming of Earth — Journal of Basic and Applied Sciences, 2023; Lightfoot and Ratzer
The authors use real-world data (not models or simulations) to determine that at the tropics, water vapor does virtually all the work of the greenhouse effect, and at the poles, where it is very dry, carbon dioxide plays no measurable role. They show that almost three-quarters of the atmosphere’s water molecules are in the Tropics, which is where the greenhouse effect takes place. They don’t say this, but the CO2 at the poles can’t cause any heating simply because there is no greenhouse effect at the poles. In fact, CO2 at the poles causes cooling.
The Impact of Human CO2 on Atmospheric CO2 — Science of Climate Change, 2021; Edwin Berry
“A basic assumption of climate change made by the United Nations Intergovernmental Panel on Climate Change (IPCC) is natural CO2 stayed constant after 1750 and human CO2 dominated the CO2 increase. IPCC’s basic assumption requires human CO2 to stay in the atmosphere longer than natural CO2. But human CO2 and natural CO2 molecules are identical. So, human CO2 and natural CO2 must flow out of the atmosphere at the same rate …” A new physics model using the IPCC’s assumptions “calculates human carbon has added only 33 [24-48] ppmv to the atmosphere as of 2020, which means natural carbon has added 100 ppmv.
The Relationship between Atmospheric Carbon Dioxide Concentration and Global Temperature for the Last 425 Million Years — Climate, 2017; Davis
“Assessing human impacts on climate and biodiversity requires an understanding of the relationship between the concentration of carbon dioxide (CO2) in the Earth’s atmosphere and global temperature (T). Here I explore this relationship empirically using comprehensive, recently-compiled databases of stable-isotope proxies from the Phanerozoic Eon (~540 to 0 years before the present) and through complementary modeling using the atmospheric absorption/transmittance code MODTRAN. Atmospheric CO2 concentration is correlated weakly but negatively with linearly-detrended T proxies over the last 425 million years. … This study demonstrates that changes in atmospheric CO2 concentration did not cause temperature change in the ancient climate.”
Antarctic temperature and CO2: near-synchrony yet variable phasing during the last deglaciation — Climate of the Past, 2019; Beeman et al.
These authors look at a far more accurate ice core from the last 18,000 years in Western Antarctica and conclude: “During the onset of the last deglaciation at 18 ka and the deglaciation end at 11.5 ka, Antarctic temperature most likely led CO2 by several centuries (by 570 years, within a range of 127 to 751 years, 68 % probability, at the T1 onset; and by 532 years, within a range of 337 to 629 years, 68 % probability, at the deglaciation end).” There are regional and some temporal anomalies, but overall they show that during about 10,000 years of warming, temperature leads and CO2 generally follows. Did I mention this was a warming phase?
Earth’s Temperature Versus the Sun, Water Vapor and CO2 — Journal of Basic and Applied Sciences, 2021; Lightfoot
Conclusion: “The increase in temperature over the decades mid-1970s to 2011 was caused by an increase in water vapor and not by an increase in CO2. The question is answered about the cause of the strong correlation between temperature and specific humidity; it is the physical relationship between temperature and specific humidity as in Figure 7. Carbon dioxide and the other non-condensing greenhouse gases (GHGs) as in Figure 3 are small, passive, and have no effect on the Earth’s temperature.”
Emissions and CO2 Concentration — An Evidence Based Approach — Atmosphere, 2023; Dengler & Reid
The authors show that as more CO2 enters the atmosphere, more will be absorbed by the sinks, so that, according to their model, future concentrations of CO2 won’t rise above 475 PPM. They validate their model with a prediction from 20 years ago and find the predicted values. They conclude: “… for the most likely IEA emission scenario of approximately constant, slightly decreasing global emissions, we can expect a maximum CO22 concentration level of approximately 475 ppm in the second half of this century. At this point, the emissions will be fully balanced by the absorptions, which is by definition the “net zero” situation.
Scrutinizing the carbon cycle and CO2 residence time in the atmosphere — Global and Planetary Change, 2017; Harde
“The anthropogenic contribution to the actual CO2 concentration is found to be 4.3%, its fraction to the CO2 increase over the Industrial Era is 15% and the average residence time 4 years.”
The Global Warming Debate: A Review of the State of Science — Pure and Applied Geophysics, 2005; Khandekar et al.
“Our review suggests that the dissenting view offered by the skeptics or opponents of global warming appears substantially more credible than the supporting view put forth by the proponents of global warming. Further, the projections of future climate change over the next fifty to one hundred years is based on insufficiently verified climate models and are therefore not considered reliable at this point in time.”
Stomatal proxy record of CO2 concentrations during the Last Termination demonstrates dynamic climate behaviour and an important role for CO2 — Quaternary Science Reviews, 2013, Steinthorsdottir et al.
Study of ancient pollen may provide a more accurate picture of the past CO2 concentrations than ice cores do. The authors find that CO2 is much more dynamic than previously believed, but it’s still too early to tell which comes first — temperature change or CO2 concentration change.
What Humans Contribute to Atmospheric CO2: Comparison of Carbon Cycle Models with Observations — Earth Sciences, 2019; Harde.
The author challenges the assumption that all CO2 increases for the last 200 years must be 100 percent man-made. He shows that the models have been created with this assumption rather than discovering it. He also shows several ways most of it could be natural, concluding: “For a conservative assessment we find … that the anthropogenic contribution to the observed CO2 increase
over the Industrial Era is significantly less than the natural influence.”
World Atmospheric CO2, Its 14C Specific Activity, Non-fossil Component, Anthropogenic Fossil Component, and Emissions (1750–2018) — Health Physics, 2022; Skrable et al.
By looking at carbon isotopes, the authors find 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.”
Clouds independently appear to have as much or greater effect than man-made CO2 on radiative forcing, World Journal of Advanced Research and Reviews, 2022; Jonas
“The patterns of behaviour of clouds, both for cloud area and cloud optical thickness, are studied over the period of available data, 1983 to 2017. There was a decrease in cloud cover over the study period, while global surface temperatures increased. The patterns of clouds and temperature indicate that the cloud cover decrease could not have been caused by the increased surface temperature. The clear implication is that the decrease in global cloud area must have been caused by some other unspecified factor, and was not caused directly or indirectly by CO2. Evaluation of the changes in clouds and CO2 over the study period indicate that this unspecified factor had as much positive impact as the increase in CO2, with respect to the amount of radiation reaching the surface (radiative forcing), and possibly a much larger positive impact. The climate models, which have zero or negative cloud impact on radiative forcing independently from CO2, need to take this into account in order to avoid over-estimating the influence of CO2.”
Atmospheric CO2 over the last 1000 years: A high-resolution record from the West Antarctic Ice Sheet (WAIS) Divide ice core — Global Biogeochemical Cycles, 2012; Ahn et al.
This is an interesting paper showing that CO2 concentration derived from Antarctic ice cores was relatively flat from 1,000 AD to 1800 AD, then it started going up:
Notice a delayed response to the Medieval Warm Period and the Little Ice Age. The WAIS ice core is most closely correlated to northern hemisphere temperatures. What was going on from 1800 to 1900? It would be reasonable to assume that a large percentage of this rise is simply from CO2 outgassing from the oceans as they warmed. In fact, that could account for most of the rise since 1800, but from 1900 on, it looks like humans have added to the CO2 concentration? How much? The ice doesn’t tell us that.
Radiation Transfer Calculations and Assessment of Global Warming by CO2 — International Journal of Atmospheric Sciences, 2017; Hermann Harde
Another HITRAN line-by-line validation of the logarithmic decay of greenhouse-gas effectiveness and sensitivity to raising temperature.
180 Years of Atmospheric CO2 Gas Analysis by Chemical Methods — Energy & Environment, 2007; Earnst-Georg Beck
“Between 1857 and 1958, the Pettenkofer process was the standard analyticalmethod for determining atmospheric carbon dioxide levels, and usually achieved anaccuracy better than 3%. These determinations were made by several scientists ofNobel Prize level distinction. Following Callendar (1938), modern climatologistshave generally ignored the historic determinations of CO2, despite the techniquesbeing standard text book procedures in several different disciplines. Chemicalmethods were discredited as unreliable choosing only few which fit theassumption of a climate CO2connection.”
What Humans Contribute to Atmospheric CO2: Comparison of Carbon Cycle Models with Observations — Earth Sciences, 2019; Hermann Harde
“… not really human activities are responsible for the observed CO2 increase and the expected temperature rise in the atmosphere, but just opposite the temperature itself dominantly controls the CO2 increase.”
How increasing CO2 leads to an increased negative greenhouse effect in Antarctica — Geophysical Research Letters, 2015; Schmithüsen, et al.
At both poles, more CO2 cools the earth’s atmosphere. This explains how that works. “These findings for central Antarctica are in contrast to the general warming effect of increasing CO2.”
Residence Time vs. Adjustment Time of Carbon Dioxide in the Atmosphere — Entropy, 2023; Peter Stallinga
“We study the concepts of residence time vs. adjustment time time for carbon dioxide in the atmosphere. The system is analyzed with a two-box first-order model. Using this model, we reach three important conclusions: (1) The adjustment time is never larger than the residence time and can, thus, not be longer than about 5 years. (2) The idea of the atmosphere being stable at 280 ppm in pre-industrial times is untenable. (3) Nearly 90% of all anthropogenic carbon dioxide has already been removed from the atmosphere.”
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