Ocean Climate Science | Science Matters

CO2 Facts Net Zero Zealots are Hiding from You

After a recent squabble with a pack of Net Zero zealots, I realized that interested people should have access to a number of CO2 science facts that are hidden from public view, and certainly won’t appear in the AI bots programmed to repeat IPCC slogans. Below is a compendiums of important contemporary findings everyone needs to know, not to be duped by the climatists. The titles are links to published research papers along with brief highlights of their importance and some pertinent graphics. There are many more skeptical findings, but these show the different analyses revealing numerous holes in IPCC swiss cheese “consensus science.”

World Atmospheric CO2, Its ¹⁴C Specific Activity, Non-fossil Component, Anthropogenic Fossil Component, and Emissions (1750–2018)

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. [My snyopsis: On CO2 Sources and Isotopes]

The graph above is produced from Skrable et al. dataset Table 2. World atmospheric CO2, its C‐14 specific activity, anthropogenic‐fossil component, non fossil component, and emissions (1750 ‐ 2018). The purple line shows reported annual concentrations of atmospheric CO2 from Energy Information Administration (EIA) The starting value in 1750 is 276 ppm and the final value in this study is 406 ppm in 2018, a gain of 130 ppm.

The red line is based on EIA estimates of human fossil fuel CO2 emissions starting from zero in 1750 and the sum slowly accumulating over the first 200 years. The estimate of annual CO2 emitted from FF increases from 0.75 ppm in 1950 up to 4.69 ppm in 2018. The sum of all these annual emissions rises from 29.3 ppm in 1950 (from the previous 200 years) up to 204.9 ppm (from 268 years). These are estimates of historical FF CO2 emitted into the atmosphere, not the amount of FF CO2 found in the air.

Atmospheric CO2 is constantly in two-way fluxes between multiple natural sinks/sources, principally the ocean, soil and biosphere. The annual dilution of carbon 14 proportion is used to calculate the fractions of atmospheric FF CO2 and Natural CO2 remaining in a given year. The blue line shows the FF CO2 fraction rising from 4.03 ppm in 1950 to 46.84 ppm in 2018. The cyan line shows Natural CO2 fraction rising from 307.51 in 1950 to 358.56 in 2018.

Residence Time vs. Adjustment Time of Carbon Dioxide in the Atmosphere

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. [My synopsis: CO2 Fluxes Not What IPCC Telling You]

Figure 3. (a) Yearly global CO 2 emissions from fossil fuels. (b) Cumulative emissions (integral of left plot). The yellow curve is the remainder of the anthropogenic CO 2 in the atmosphere if we assume a residence time in the sink much longer than the 5-year residence time in the atmosphere; in this case τs=50τa was used. (Source of data: Our World In Data [8]).

In these years, the amount of CO2 in the atmosphere has risen from 280 ppm (2268 Gt) to 420 ppm (3403 Gt), an increment of 1135 Gt. Of these, 202.3 Gt (17.8%) would be attributable to humans and the rest, 932.7 Gt (82.2%), must be from natural sources.

In view of this, curbing carbon emissions seems rather fruitless; even if we destroy the fossil-fuel-based economy (and human wealth with it), we would only delay the inevitable natural scenario by a couple of years.

The Scientific Case Against Net Zero: Falsifying the Greenhouse Gas Hypothesis

The scientific case against net zero: falsifying the greenhouse gas hypothesis — Journal of Sustainable Development, 2024; Michael Simpson

There is a suggestion (IPCC) that the residence time of CO2 in the atmosphere is different for anthropogenic CO2 and naturally occurring CO2. This breaks a fundamental scientific principle, the Principle of Equivalence. That is: if there is equivalence between two things, they have the same use, function, size, or value (Collins English Dictionary, online). Thus, CO2 is CO2 no matter where it comes from, and each molecule will behave physically and react chemically in the same way.

The results imply that the effect of man-made CO2 emissions does not appear to be sufficiently strong to cause systematic changes in the pattern of the temperature fluctuations. In other words, our analysis indicates that with the current level of knowledge, it seems impossible to determine how much of the temperature increase is due to emissions of CO2. Dagsvik et al. 2024

It is well-known that the residence time of CO2 in the atmosphere is approximately 5 years (Boehmer-Christiansen, 2007: 1124; 1137; Kikuchi, 2010). Skrable et al., (2022), show that accumulated human CO2 is 11% of CO2 in air or ~46.84ppmv based on modelling studies. Berry (2020, 2021) uses the Principle of Equivalence (which the IPCC violates by assuming different timescales for the uptake of natural and human CO2) and agrees with Harde (2017a) that human CO2 adds about 18ppmv to the concentration in air. These are physically extremely small concentrations of CO2 which suggest most CO2 arises from natural sources. It can be concluded that the IPCC models are wrong and human CO2 will have little effect on the temperature. [My synopsis: Straight Talk on Climate Science and Net Zero]

Better calculations of the human contribution to atmospheric CO2 concentrations are available and it is small ~18ppmv (Skrable et al., 2022; Berry, 2020; Harde 2017a & 2017b; Harde, 2019; Harde 2014). The phase relation between temperature and CO2 concentration changes are now clearly understood; temperature increases are followed by increases in CO2 likely from outgassing from the ocean and increased biological activity (Davis , 2017; Hodzic and Kennedy, 2019; Humlum, 2013; Salby, 2012; Koutsoyiannis et al, 2023 & 2024).

Decoupling CO2 from Climate Change

Decoupling CO2 from Climate Change— International Journal of Geosciences, 2024; Nelson & Nelson

Historical data were reviewed from three different time periods spanning 500 million years. It showed that the curves and trends were too dissimilar to establish a connection. Observations from CO2/temp ratios showed that the CO2 and the temperature moved in opposite directions 42% of the time. Many ratios displayed zero or near zero values, reflecting a lack of response. As much as 87% of the ratios revealed negative or near zero values, which strongly negate a correlation.

The fact that the curves were wildly divergent suggests there were major factors in play that were not considered. Excluding water vapor from the analysis may be one reason, as explained in sections 4 and 5. The list of other contributing factors is extensive. For example, changes in the orbital paths of the sun and planets, as suggested by the Milankovitch Cycles, may have had an effect. Changes in the sun’s radiation intensity may play a role. The Earth’s volcanism, nuclear fission at its core, radioactive decay, or changes in the magnetic fields may have an effect over millions of years. These are only a few possibilities not considered in the hypothesis.

Figure 10. This graph is the cloud fraction and is set forth on the left vertical axis. The temperature is on the right vertical axis and the horizontal axis represents the observation year. The information was extrapolated from figures prepared by Hans-Rolf Dubal and Fritz Vahrenholt [37].

Studies have reported that the rise in the CO2 concentration lagged behind temperature increases by 400 to 1000 years [6]. In 2007 the IPCC stated at page 105 [7] “However, it now appears that the initial climatic change preceded the change in CO2 but was enhanced by it (Section 6.4)” But there was no proof provided in section 6.4 supporting the enhancement theory. They stated on page 442 “it may be the result of increased ocean heat transports due to either an enhanced thermohaline circulation” (citations) “or increased flow of surface ocean currents.” A lagging CO2 concentration after the temperature changes contradicts the Greenhouse-CO2 hypothesis, i.e. a rise in CO2 concentration results in warming.

The Relationship between Atmospheric Carbon Dioxide Concentration and Global Temperature for the Last 425 Million Years

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.”

Figure 5. Temperature (T) and atmospheric carbon dioxide (CO2) concentration proxies during the Phanerozoic Eon. Davis (2017)

Reconstruction of Atmospheric CO2 Background Levels since 1826 from Direct Measurements near Ground

Reconstruction of Atmospheric CO2 Background Levels since 1826 from Direct Measurements near Ground Ernst-Georg Beck—Science of Climate Change Ernst-Georg Beck (2022)

The data also suggest higher levels in the first half of the 19th century than reconstructed from commonly used ice cores. Using modern MLO CO2 data, we can calculate a centennial average for the 20th century 1901–2000 of 331.38 ppm and of a MBL [Marine Boundary Level samples]in the 19th century (1826–1900) of 322.67. This is a growth rate of +2.6 % in contrast to about 30 % as derived from ice cores and therefore within measurement variability. Analysing the new series of directly measured CO2 MBL levels from 1926 to 2010 suggests a possible cyclic behaviour. The CO2 MBL levels since 1826 to 2008 show a good correlation to the global SST (Kaplan, KNMI; see Figure 26) with a CO2 lag of 1 year after SST from cross correlation (Figure 26a). Kuo et al. (1990) had derived 5 months lag from MLO data alone.

Stomata data confirm the CO2 MBL reconstruction as well as the raw data showing high CO2-levels in the 1930s and 40s at higher temperatures. This is the pre-condition for the inverse stomata/CO2 relation.

About Historical CO2-Data since 1826: Explanation of the Peak around 1940 Hermann Harde

About Historical CO2-Data since 1826: Explanation of the Peak around 1940–Science of Climate Change Hermann Harde, 2023

An extensive compilation of almost 100.000 historical data about CO2 concentration measurements between 1826 and 1960 has been published as post mortem memorial edition of the late Ernst-Georg Beck (Beck 2022). Different to the widely used interpretation of proxy data, Beck’s compilation contains direct measurements of chemically analysed air samples with much higher accuracy and time resolution than available from ice core or tree ring data.

Beck already found a high correlation of the CO2 level data to the global Sea Surface Temperature (SST) series of the Royal Netherlands Meteorological Institute (Kaplan, KNMI). Supported by different observations of CO2 enriched air at the coast (North Sea, Barents Sea, Northern Atlantic) he suggested that warmer ocean currents over the Northern Atlantic are the sources of the enhanced CO2-levels.

Figure 26. Annual atmospheric CO2 background level 1856–2008 compared to SST (Kaplan, KNMI); red ine: CO2 MBL reconstruction 1826–1959 (Beck), 1960–2008 (MLO); blue line: Annual SST (Kaplan) 1856 –2003; a) cross correlation of SST and CO2 MBL showing correlation of r=0.668 and a lag of 1 year for CO2 after global SST. Beck 2010

In this contribution we compare the temperature sensitivity of oceanic and land emissions and their expected contributions to the atmospheric CO2 mixing ratio. Our simulations with a land-air temperature series (Soon et al. 2015) alone, or in combination with sea surface data (HadSST4, Kennedy et al. 2019) can well reproduce the increased mixing ratio over the 30s to 40s, the consecutive decline over the 50s and the additional rise up to 2010. This stronger variation cannot be explained only by fossil fuel emissions, which show a monotonic increase over the Industrial Era.

Atmospheric CO2: Exploring the Role of Sea Surface Temperatures and the Influence of Anthropogenic CO2 Bernard Robbins

Atmospheric CO2: Exploring the Role of Sea Surface Temperatures and the Influence of Anthropogenic CO2 — Science of Climate Change, 2025; Robbins

“ Using SST and Mauna Loa datasets, three methods of analysis are presented that seek to identify and estimate the anthropogenic and, by default, natural components of recent increases in atmospheric CO2, an assumption being that changes in SSTs coincide with changes in nature’s influence, as a whole, on atmospheric CO2 levels.

Figure 16: Atmospheric CO2 measurements, shown in Blue (chemical measurements to 1960 and Mauna Loa measurements from 1960) and global SSTs (shown in Violet). The error margins and confidence intervals are as supplied with the chemical CO2 and SST datasets.

The findings of the analyses suggest that an anthropogenic component is likely to be around 20 %, or less, of the total increase since the start of the industrial revolution. The inference is that around 80 % or more of those increases are of natural origin, and indeed the findings suggest that nature is continually working to maintain an atmospheric/surface CO2 balance, which is itself dependent on temperature.”

Multivariate Analysis Rejects the Theory of Human-caused Atmospheric Carbon Dioxide Increase: The Sea Surface Temperature Rules

Multivariate Analysis Rejects the Theory of Human-caused Atmospheric Carbon Dioxide Increase: The Sea Surface Temperature Rules–Science of Climate Change Dai Ato 2024

“The main factor governing the annual increase in atmospheric CO2 concentration is the SST [sea surface temperature] rather than human emissions.” – Ato, 2024

Another day, another new scientific paper has been published reporting efforts to curb anthropogenic CO2 emissions are “meaningless.” In this study multiple linear regression analysis was performed comparing SST versus anthropogenic CO2 emissions as explanatory factors and the annual changes in atmospheric CO2 as the objective variable over the period 1959-2022.

The model using the SSTs (NASA, NOAA, UAH) best explained the annual CO2 change (regression coefficient B = 2.406, P = <0.0002), whereas human emissions were not shown to be an explanatory factor at all in annual CO2 changes (regression coefficient B = 0.0027, P = 0.863). Most impressively, the predicted atmospheric CO2 concentration using the regression equation derived from 1960-2022 SSTs had an extremely high correlation coefficient of r = 0.9995.

Thus, not only is the paradigm that says humans drive atmospheric CO2 changes wrong, but “the theory that global warming and climate change are caused by human-emitted CO2 is also wrong.”

“SST has been the determinant of the annual changes in atmospheric CO2 concentrations and […] anthropogenic emissions have been irrelevant in this process, by head-to-head comparison.”

Revisiting the greenhouse effect – a hydrological perspective

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

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.

Figure 1. Typical ranges of isotopic signatures δ13C for each of the pools interacting with atmospheric CO2, and related exchange processes.

The results of the analyses in this paper provide negative answers to the research questions posed in the Introduction. Specifically:

♦ From modern instrumental carbon isotopic data of the last 40 years, no signs of human (fossil fuel) CO2 emissions can be discerned;
♦ Proxy data since the Little Ice Age suggest that the modern period of instrumental data does not differ, in terms of the net isotopic signature of atmospheric CO2 sources and sinks, from earlier centuries.

Comment and Declaration on the SEC’s Proposed Rule “The Enhancement and Standardization of Climate-Related Disclosures for Investors”

Comment and Declaration on the SEC’s Proposed Rule— Happer and LIndzen,

The Logarithmic Forcing from CO2 Means that Its Contributions to Global Warming is Heavily Saturated, Instantaneously Doubling CO2 Concentrations from 400 ppm to 800 ppm, a 100% Increase, Would Only Diminish the Thermal Radiation to Space by About 1.1%, and therefore tiny changes of Earth’s surface temperature, on the order of 1° C (about 2° F). Thus Confirming There is No Reliable Scientific Evidence Supporting the Proposed Rule.

This means that from now on our emissions from burning fossil fuels could have little impact on global warming. There is no climate emergency. No threat at all. We could emit as much CO2 as we like, with little warming effect.

Saturation also explains why temperatures were not catastrophically high over the hundreds of millions of years when CO2 levels were 10-20 times higher than they are today.

Further, saturation also provides another reason why reducing the use of fossil fuels to“net zero” by 2050 would have a trivial impact on climate, contradicting the theory there is a climate related risk from fossil fuel and CO2 emissions.

Laws of Physics Define the Insignificant Warming of Earth by CO2

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.

Calculating the increase in the heat content of the atmosphere caused by increased CO2 is the method for determining the rise in Earth’s temperature. An increase from 311 ppm to 418 ppm causes a maximum rise of 0.006oC from McMurdo to Taoudenni, Mali, in the Sahara Desert. This value indicates the temperature increase is too small to measure, i.e., negligible [15].

This study is a significant step forward in the science of the Earth’s atmosphere. It provides robust quantitative evidence that the overall warming by CO2 is insignificant, and water vapor is the most significant greenhouse gas.

Footnote: Clashing CO2 Paradigms

For insight into the two conflicting viewpoints regarding CO2 and temperatures, see:

CO2 Fluxes Are Not Like Cash Flows

2026 IPCC Global Warming Claims Not Only Wrong, But Impossible

Posted on 16 Days Ago by Ron Clutz

Climate as heat engine. A heat engine produces mechanical energy in the form of work W by absorbing an amount of heat Qin from a hot reservoir (the source) and depositing a smaller amount Qout into a cold reservoir (the sink). (a) An ideal Carnot heat engine does the job with the maximum possible efficiency. (b) Real heat engines are irreversible, and some work is lost via irreversible entropy production TδS. (c) For the climate system, the ultimate source is the Sun, with outer space acting as the sink. The work is performed internally and produces winds and ocean currents. As a result, Qin = Qout.

Update 2026

Kevin Mooney writes at Real Clear Energy Trump Is Right: Science Demands That We Overturn the ‘Endangerment Finding’ Excerpts in italics with my bolds.

Taking on the climate establishment with research that debunks the media narrative.

Science is on the side of the Trump administration’s efforts to unwind the U.S. from costly climate regulations—much to the consternation of major media platforms that peddle unfounded, politically motivated assertions.

That’s why fresh research and updated findings into the impact of carbon dioxide emissions should figure more prominently into an otherwise laudatory and audacious White House strategy to repeal the 2009 endangerment finding. In my new book, Climate Porn: How and Why Anti-Population Zealots Fabricate Science, while Targeting American Capitalism, Freedom, and Independence, I review the science and common sense that reiterates CO2 is a naturally occurring, highly beneficial compound. Indeed, it is critical to life on Earth. And yet, the Obama administration saw fit to declare CO2 a “pollutant” in its endangerment finding, which found that CO2 poses a threat to public health and welfare. This enabled the EPA to unleash a wave of costly climate regulations.

Trump, Zeldin, Wright, and crew should not just rely on legal arguments, but rather double down on the science as they take on the endangerment finding. Posterity will thank them.

Recent Research Discredits Climatists’ Fearful Claims

In light of the above context, I am posting a recent and significant rebuttal of the IPCC “consensus” science that is full of holes like swiss cheese. Ad Huijser recently published a paper explaining why IPCC claims about global warming are contradicted by observations of our Earth thermal system including a number of internal and external subsytems. The title Global Warming and the “impossible” Radiation Imbalance links to the pdf. This post is a synopsis to present the elements of his research findings, based on the rich detail, math and references found in the document. Excerpts in italics with my bolds and added images. H/T Kenneth Richard and No Tricks Zone.

Abstract

Any perturbation in the radiative balance at the top of the atmosphere (TOA) that induces a net energy flux into- or out of Earth’s thermal system will result in a surface temperature response until a new equilibrium is reached. According to the Anthropogenic Global Warming (AGW) hypothesis which attributes global warming solely to rising concentrations of Greenhouse gases (GHGs), the observed increase in Earth’s radiative imbalance is entirely driven by anthropogenic GHG-emissions.

However, a comparison of the observed TOA radiation imbalance with the assumed GHG forcing trend reveals that the latter is insufficient to account for the former. This discrepancy persists even when using the relatively high radiative forcing values for CO2 adopted by the Intergovernmental Panel on Climate Change (IPCC), thereby challenging the validity of attributing recent global warming exclusively to human-caused GHG emissions.

In this paper, Earth’s climate system is analyzed as a subsystem of the broader Earth Thermal System, allowing for the application of a “virtual balance” approach to distinguish between anthropogenic and other, natural contributions to global warming. Satellite-based TOA radiation data from the CERES program (since 2000), in conjunction with Ocean Heat Content (OHC) data from the ARGO float program (since 2004), indicate that natural forcings must also play a significant role. Specifically, the observed warming aligns with the net increase in incoming shortwave solar radiation (SWIN), likely due to changes in cloud cover and surface albedo. Arguments suggesting that the SWIN trend is merely a feedback response to GHG-induced warming are shown to be quantitatively insufficient.

This analysis concludes that approximately two-thirds of the observed global warming must be attributed to natural factors that increase incoming solar radiation, with only one-third attributable to rising GHG-concentrations. Taken together, these findings imply a much lower climate sensitivity than suggested by IPCC-endorsed Global Circulation Models (GCMs).

Introduction

On a global scale and over longer periods of time, the average surface temperature of our climate system reacts similarly to that of a thermal system such as a pot of water on a stove: when the incoming heat is steady and below boiling, the system stabilizes when the heat loss (via radiation and convection) equals the input. Analogously, Earth’s surface-atmosphere interface is the main absorber and emitter of heat. Reducing the “flame” (solar input) leads to cooling, regardless of the total heat already stored in the system. The system’s average temperature will drop as well, as soon as the heating stops. So, no sign of any “warming in the pipeline” for such a simple system.

The two transport mechanisms, air and ocean, operate on different timescales. Air has a low specific heat capacity, but high wind speeds make it a fast medium for heat transfer. Oceans, by contrast, have a high specific heat capacity but move more slowly. The Atlantic Meridional Overturning Circulation (AMOC) with the well-known Gulf Stream carrying warm water from south to north, can reach speeds up to about 3 m/s. But its warm current remains largely confined to surface layers due to limited solar radiation penetration and gravity-induced stratification. With a path-lengths of up to 8,000 km and an average speed of 1.5 m/s, ocean heat takes approximately 2 months to travel from the Gulf of Mexico to the Arctic. This is comparable to the 1 to 2 months delay between solar input and temperature response in the annual cycle, suggesting that oceanic heat transport is part of the climate system’s normal operation. Climate adaptation times from anthropogenic influences are estimated at 3 to 5 years. If “warming in the pipeline” exists, it must be buried in the much colder, deeper ocean layers.

ARGO float data since 2004 show substantial annual increases in Ocean Heat Content (OHC), sometimes expressed in mind-boggling terms such as 10²² joules per year (see Fig.1). While this may sound alarming [1,2], when converted to flux, it represents less than 1 W/m², a mere 0.6% of the average 160 W/m² of absorbed solar energy at the surface. All the rest is via evaporation, convection and ultimately by radiation sent back to space after globally being redistributed by wind and currents.

Fig. 1. Ocean Heat Content (OHC) anomaly from 0–2000 meters over time, shown as 3-month and annual moving averages (CMAA), along with their time derivatives. Notable are the relatively large variations, likely reflecting the influence of El Niño events. The average radiative imbalance at the top of the atmosphere (TOA), estimated at 0.85 W/m², corresponds approximately to the midpoint of the time series (around 2015). Data: https://www.ncei.noaa.gov/access/global-ocean-heat-content/basin_heat_data.html [7].

This raises the question: Why would extra GHGs that have only a limited effect on the 99.4% of the outgoing flux, have affected this 0.6% residue during a couple of decennia in such a way that we should be scared about all that “warming in the pipeline” as Hansen et al. [2] are warning us for? In the following sections, we examine data showing that observed trends in the radiation imbalance and OHC are better explained by the internal dynamics of the Earth’s thermal system and natural forcings such as from increasing solar radiation, rather than solely by GHG emissions.

Estimating our climate’s thermal capacity CCL

The rather fast responses of our climate indicates that the thermal capacity of our climate must be much less than the capacity of the entire Earth thermal system. This climate heat capacity CCL depends on how sunlight is being absorbed, how that heat is transferred to the atmosphere and which part of it is being stored in either land or ocean.

At continental land-area, sunlight is absorbed only at the very surface where the generated heat is also in direct contact with the atmosphere. Seasonal temperature variations don’t penetrate more than 1 to 2 meters deep in average and as a consequence, storage of heat is relatively small. Sunlight can penetrate pure water to several hundred meters deep, but in practice, penetration in the oceans is limited by scattering and absorption of organic and inorganic material. A good indication is the depth of the euphotic zone where algae and phytoplankton live, which need light to grow. In clear tropical waters where most of the sunlight hits our planet, this zone is 80 to 100 m deep [12].

Another important factor in our climate’s heat capacity is how this ocean layer of absorbed heat is in contact with the atmosphere. Tides, wind, waves and convection continuously mix the top layer of our oceans, by which heat is easily exchanged with the atmosphere. This mixed-layer is typically in the order of 25 – 100 m, dependent on season, latitude and on the definition of “well mixed” [13]. Below this ~100 m thick top-layer, where hardly any light is being absorbed and the mixing process has stopped, ocean temperatures drop quickly with depth. As the oceans’ vertical temperature gradient at that depth doesn’t support conductive nor convective heat flows going upward, climate processes at the surface will thus become isolated from the rest of the Earth’ thermal system.

Figure 4 with the Change in Ocean Heat Content vs. Depth over the period 2004 – 2020 obtained via the ARGO-floats [6,14], offers a good indication for the average climate capacity CCL. It shows the top layer with a high surface temperature change according to the observed global warming rate of about 0.015 K/year, and a steep cut off at about 100 m depth in line with the explanation above. Below the top layer, temperature effects are small and difficult to interpret, probably due to averaging over all kinds of temperature/depth profiles in the various oceans ranging from Tropical- to Polar regions.

In case of a “perfect” equilibrium (N = 0, dTS/dt = 0), all of the absorbed sunlight up to about 100 m deep, has to leave on the ocean-atmosphere interface again. However, deep oceans are still very cold with a stable, negative temperature gradient towards the bottom. This gradient will anyhow push some of the absorbed heat downwards. Therefore, even at a climate equilibrium with dTS/dt= 0, we will observe N > 0. With the large heat capacity of the total ocean volume, that situation will not change easily, as it takes about 500 years with today’s N ≈ +1 W/m2 to raise its average temperature just 1°C.

The Earth’s climate system can thus be regarded as a subset of the total Earth’s thermal system (ETS) responding to different relaxation times. The climate relaxes to a new equilibrium within 3–5 years, while the deeper oceans operate on multidecadal or even longer timescales, related to their respective thermal capacities C for the ETS, and CCL for the climate system.

The (near) “steady state” character of current climate change

Despite the ongoing changes in climate, the current state can be considered a “near” steady-state. The GHG forcing trend has been pretty constant for decades. Other forcings, primarily in the SW channel, are also likely to change slowly and can be approximated as having constant trends over decadal timescales. Similarly, despite yearly fluctuations, the surface temperature trend has remained fairly stable since 2000.

This analysis strengthens the conclusion that the increase in both N(t) and N0(t) are not a direct consequence of greenhouse gas emissions, but rather of enhanced forcing in the SW-channel.

The preceding analysis highlights how the IPCC’s assumptions diverge significantly from observed reality. While the IPCC model components may collectively reproduce the observed warming trend, they fail to individually align with key observational data, in particular the Ocean Heat Content.

Figure 6 also illustrates that changes in cloudiness are more pronounced on the Northern Hemisphere, especially at mid-latitudes and over Western Europe. For example, the Dutch KNMI weather-station at Cabauw (51.87°N, 4.93oE), where all ground-level radiation components are monitored every 10 minutes, recorded an increase in solar radiation of almost +0.5 W/m²/year since 2000 [26]. Applying the 0.43 net-CRE factor (conservative for this latitude), we estimate a local forcing trend dFSW/dt ≈ 0.2 W/m²/year. This is an order of magnitude larger than the GHG forcing (0.019–0.037 W/m²/year). Even with the IPCC values, GHGs can just account for about 16% of the warming at this station. The average temperature trend for this rural station located in a polder largely covered by grassland, is with ~ +0.043 K/year almost 3x the global average. This, nor the other trends mentioned above can be adequately explained by the IPCC’s GHG-only model.

The IPCC places strong emphasis on the role of climate feedbacks in amplifying the warming effect of greenhouse gases (GHGs) [8]. These feedbacks are considered secondary consequences of Anthropogenic Global Warming, driven by the initial temperature increase from GHGs. Among them, Water-Vapor feedback is the most significant. A warmer atmosphere holds more water vapor (approximately +7%/K) and since water vapor is a potent GHG, even a small warming from CO2 can amplify itself through enhanced evaporation.

Other feedbacks recognized by the IPCC include Lapse Rate, Surface Albedo, and Cloud feedbacks [8], all of which are inherently tied to the presence and behavior of water in its various phases. Therefore, these feedbacks are natural responses to temperature changes, regardless of the original cause of warming, be it GHGs, incoming solar variability, or internal effects. They are not additive components to natural climate sensitivity, as treated by the IPCC, but rather integral parts of it [4].

This analysis reinforces a fundamental point: climate feedbacks are not external modifiers of climate sensitivity; rather, they are inherent to the system. Their combined effect is already embedded in the climate response function. The IPCC’s treatment of feedbacks as additive components used to “explain” high sensitivities in GCMs is conceptually flawed. Physically, Earth’s climate is governed by the mass balance of water in all its phases: ice, snow, liquid, vapor, and clouds. The dynamics between these phases are temperature-sensitive, and they constitute the feedback processes. Feedbacks aren’t just add-ons to the climate system, they are our climate.

Ocean Heat Content increase

In the introduction, the “heat in the pipeline” concept: the idea that heat stored in the deep, cold ocean layers could later resurface to significantly influence surface temperatures, was challenged. Without a substantial decrease in surface temperatures to reverse ocean stratification, this seems highly unlikely. Large and rapid temperature fluctuations during the pre-industrial era with rates up to plus, but also minus 0.05 K/year over several decennia as recorded in the Central England Temperature (CET) series [27], more than three times the rate observed today, further undermine the notion of a slow-release heat mechanism dominating surface temperature trends.

Ocean Heat Content must be related to solar energy. It is the prime source of energy heating the Earth thermal system. Almost 1 W/m2 of that 240 W/m2 solar flux that is in average entering the system, is presently remaining in the oceans. This is an order of magnitude larger than the estimated 0.1 W/m2 of geothermal heat upwelling from the Earth inner core [11]. Extra greenhouse gasses don’t add energy to the system, but just obstruct cooling. As shown in Section 5.3, this accounts for a radiation imbalance offset τ dFGHG/dt, or equivalent to a contribution to dOHC/dt of only about 0.08 W/m2.
.
As redistribution of “heat in the pipeline” will not change the total OHC, roughly 3/4 of the observed positive trend in OHC must at least be attributed to rising solar input. The oceans act in this way as our climate system’s thermal buffer. It will mitigate warming during periods of increased solar input and dampen cooling when solar input declines, underscoring its critical role in Earth’s climate stability.

The strong downwards slope in the OHC before 1970 confirms the observation in Section 5.4 and expressed by (12) that around the turning point t = ζ, the forcing trend in the SW-channel had to be negative. Moreover, the rather slowly increasing 700-2000m OHC data in Fig.7 indicate that most of the fluctuations have occurred relatively close to the surface. Heat from e.g. seafloor volcanism as “warming from below”, is expected to show up more pronounced in this 700-2000m OHC-profile. Although we cannot rule out geothermal influences [29], this observation makes them less likely.

ERBE measurements of radiative imbalance.

As the OHC seems to be primarily coupled to SWIN, the most plausible cause would involve rapid changes in SW-forcing. A sudden drop in cloud-cover might explain such changes, but no convincing observations could be found for the 1960-1980 period. Alternatively, changes in the latitudinal distribution of cloud-cover as illustrated by Fig.6, can result in similar radiative impacts due to the stark contrast between a positive radiation imbalance in the Tropics and a very negative imbalance at the Poles. The ENSO-oscillations in the Pacific Ocean around the equator are a typical example for such influences, as also illustrated in Fig.3 [10]. Shifts in cloud distribution are linked to changes in wind patterns and/or ocean currents, reinforcing the idea as indicated in Section 1, that even minor disruptions in horizontal heat transport can trigger major shifts in our climate’s equilibrium [29, 30]. Sharp shifts in Earth’s radiation imbalance like the one around 1970 as inferred from Fig.7, may even represent one of those alleged tipping points. But in this case, certainly not one triggered by GHGs. Ironically, some climate scientists in the early 1970s predicted an impending (Little) Ice Age [31].

While additional data (e.g. radiation measurements) are needed to draw firm conclusions, the available evidence already challenges the prevailing GHG-centric narrative again. GHG emissions, with their near constant forcing rate, cannot account for the timing nor the magnitude of historical OHC trends, as NOAA explicitly suggests [32]. Similarly, claims by KNMI that “accelerations” in radiation imbalance trends are GHG-driven [1], are not supported by data. And finally, the alarms around “heat in the pipeline” must be exaggerated if not totally misplaced. Given the similarities in radiation imbalance and GHG forcing rates around 1970 with today’s situation, we must conclude that this assumed heat manifested itself at that time apparently as “cooling in the pipeline”.

However, warnings for continued warming even if we immediately stop now with emitting GHGs are nevertheless, absolutely justified. Only, it isn’t warming then from that heat in the pipeline due to historical emissions that will boost our temperatures. Warming will continue to go on as long as natural forcings will be acting. These are already today’s dominant drivers behind global temperature trends. And unfortunately, they will not be affected by the illusion of stopping global warming as created by implementing Net-Zero policies.

Summary and conclusions

This analysis demonstrates that a global warming scenario driven solely by greenhouse gases (GHGs) is inconsistent with more than 20 years of observations from space and of Ocean Heat Content. The standard anthropogenic global warming (AGW) hypothesis, which attributes all observed warming to rising GHG concentrations, particularly CO2, cannot explain the observed trends. Instead, natural factors, especially long-term increase in incoming solar radiation, appear to play a significant and likely dominant role in global warming since the mid-1970s.

The observed increase in incoming solar radiation cannot be accounted for by the possible anthropogenic side effects of Albedo- and Cloud-feedback. All evidence points to the conclusion that this “natural” forcing with a trend of about 0.035 W/m2/year is equal to, or even exceeds the greenhouse gas related forcing of about 0.019 W/m2/year. Based on these values, only 1/3rd of the observed temperature trend can be of anthropogenic origin. The remaining 2/3rd must stem from natural changes in our climate system, or more broadly, in our entire Earth’ thermal system.

Moreover, the observed increase in Earth’s radiation imbalance appears to be largely unrelated to GHGs. Instead, it correlates strongly with natural processes driving increased incoming solar radiation. Claims of “acceleration” in the radiation imbalance due to GHG emissions are not supported by the trend in accurately measured GHG concentrations. If any acceleration in global warming is occurring, it is almost certainly driven by the increasing flux of solar energy—an inherently natural phenomenon not induced by greenhouse gases.

In summary, this analysis challenges the notion that GHGs are the primary drivers of recent climate change. It underscores the importance of accounting for natural variability, especially in solar input, when interpreting warming trends and evaluating climate models.

Note: Dr. Ad Huijser, physicist and former CTO of Philips and director of the Philips Laboratories, describes himself as “amateur climatologist”. However his approach to climate physics is quite professional, I think.

See Also:

Our Atmospheric Heat Engine

Yearend 2025, Cooling Temperatures Reducing CO2 Rise

Posted on January 6 by Ron Clutz

2025 ended with a steadily declining rate of rising CO2 in the atmosphere following a 20 month cooling since April 2024, peak of an unusual and unexplained warming spike. Historical records show that around 1875 was the coldest time in the last 10,000 years. That was the end of the Little Ice Age (LIA), and since then temperatures have warmed at an average rate of about 0.5C per century. The recovery of the biosphere and ocean warming resulted in rising levels of CO2 in the atmosphere.

Syun-Ichi Akasofu, founder of the University of Alaska Fairbanks’ Geophysical Institute reported on this pattern in 2009.

At times, there are warming spikes, in the 1930s and 40s for example, and the rate of rising CO2 goes up. At other times, such as 1950s and 60s, temperatures cool, and rising CO2 slows down. More recently, in 2023 and 24, we saw temperatures spike up before falling back down in 2025. [Note: A study of ocean biochemistry processes confirms that since the end of the LIA rising temperatures have been accompanied by rising CO2 at a rate of ~2 ppm per year. [ See: Slam Dunk: Δtemp Drives Δco2, Ocean Biochemistry at Work ]

Furthermore, going back to previous warmings prior to the satellite record shows that the entire rise of 0.8C since 1947 is due to oceanic, not human activity.

Importantly, the theory of human-caused global warming asserts that increasing CO2 in the atmosphere changes the baseline and causes systemic warming in our climate. On the contrary, all of the warming since 1947 was episodic, coming from three brief events associated with oceanic cycles. And in 2024 we saw an amazing episode with a temperature spike driven by ocean air warming in all regions, along with rising NH land temperatures, now dropping well below its peak.

Previously I have demonstrated that changes in atmospheric CO2 levels follow changes in Global Mean Temperatures (GMT) as shown by satellite measurements from University of Alabama at Huntsville (UAH). A link to that background post is provided later below.

My curiosity was piqued by the remarkable GMT spike starting in January 2023 and rising to a peak in April 2024. GMT has declined steadily, and now 20 months later, the anomaly is 0.30C down from 0.94C. I also became aware that UAH has recalibrated their dataset due to a satellite drift that can no longer be corrected. The values since 2020 have shifted slightly in version 6.1, as shown in my recent report UAH Ocean Stays Cool, SH Land Warms, October 2025, The data here comes from UAH record of temperatures measured in the lower troposphere (TLT).

This post updates the analysis with the complete observations for 2025, testing the premise that temperature changes are predictive of changes in atmospheric CO2 concentrations. The chart at the top shows the two monthly datasets: CO2 levels in blue reported at Mauna Loa, and Global temperature anomalies in purple reported by UAHv6.1, both through December 2025. Would such a sharp increase in temperature be reflected in rising CO2 levels, according to the successful mathematical forecasting model? Would CO2 levels decline as temperatures dropped following the peak?

The answer is yes: that temperature spike resulted
in a corresponding CO2 spike as expected.
And lower CO2 levels followed the temperature decline.

Above are UAH temperature anomalies compared to CO2 monthly changes year over year.

Changes in monthly CO2 synchronize with temperature fluctuations, which for UAH are anomalies referenced to the 1991-2020 period. CO2 differentials are calculated for the present month by subtracting the value for the same month in the previous year (for example December 2025 minus December 2024). Temp anomalies are calculated by comparing the present month with the baseline month. Note the recent CO2 upward spike and drop following the temperature spike and drop.

The table below shows clearly the pattern of observed temperatures declining along with declining rates of rising observed CO2. The CO2 rate peaked at 4.41 ppm, then declined over the next 21 months to 2.09 ppm, nearly the baseline rate since the LIA. There are fluctuations in the CO2 monthly response since the differential is influenced by the previous year as well as current year. By 2025/12, the rate of 2.09 ppm was less than half the peak rate of 4.41 ppm.

Month	temperature anomaly	co2 Diff. from previous year
2024\1	0.79	3.32
2024\2	0.86	4.23
2024\3	0.87	4.41
2024\4	0.94	3.14
2024\5	0.78	2.87
2024\6	0.70	3.25
2024\7	0.74	3.72
2024\8	0.75	3.31
2024\9	0.80	3.53
2024\10	0.73	3.56
2024\11	0.64	3.39
2024\12	0.62	3.54
2025\1	0.46	3.85
2025\2	0.50	2.54
2025\3	0.58	2.77
2025\4	0.61	3.13
2025\5	0.50	3.61
2025\6	0.48	2.70
2025\7	0.36	2.32
2025\8	0.39	2.49
2025\9	0.53	2.34
2025\10	0.53	2.49
2025\11	0.43	2.61
2025\12	0.30	2.09

The final proof that CO2 follows temperature due to stimulation of natural CO2 reservoirs is demonstrated by the ability to calculate CO2 levels since 1979 with a simple mathematical formula:

For each subsequent year, the CO2 level for each month was generated

CO2 _{this month this year} = a + b × Temp _{this month this year} + CO2 _{this month last year}

The values for a and b are constants applied to all monthly temps, and are chosen to scale the forecasted CO2 level for comparison with the observed value. Here is the result of those calculations.

In the chart calculated CO2 levels correlate with observed CO2 levels at 0.9988 out of 1.0000. This mathematical generation of CO2 atmospheric levels is only possible if they are driven by temperature-dependent natural sources, and not by human emissions which are small in comparison, rise steadily and monotonically. For a more detailed look at the recent fluxes, here are the results since 2015, an ENSO neutral year.

For this recent period, the calculated CO2 values match well the annual highs, while some annual generated values of CO2 are slightly higher or lower than observed at other months of the year. Still the correlation for this period is 0.9942.

Key Point

Changes in CO2 follow changes in global temperatures on all time scales, from last month’s observations to ice core datasets spanning millennia. Since CO2 is the lagging variable, it cannot logically be the cause of temperature, the leading variable. It is folly to imagine that by reducing human emissions of CO2, we can change global temperatures, which are obviously driven by other factors.

Background on Analytics and Methodology

Temps Cause CO2 Changes, Not the Reverse. 2024 Update

Slam Dunk: Δtemp Drives Δco2, Ocean Biochemistry at Work

Posted on December 30 by Ron Clutz

Peter Smith explains in his Quadrant article Shunned by Sanctitudinous Science. Excerpts in italics with my bolds and added images. Synopsis of Ivan Kennedy paper follows later.

When coffeeing with a group of conservative friends as I do on Fridays, one of our number, Professor Emeritus Ivan Kennedy, said something to the effect that there were no scientific alternative theories to the IPCC’s explanation of global warming except for his.

I was taken aback. Surely, even within my limited knowledge, William Happer (Princeton) and Richard Lindzen (MIT) hypothesise that the effect of CO2 on warming progressively declines. Nobel Prize winner Dr John Clauser hypothesises that reflective cumulus clouds created by water vapour, engendered by modest warming, act as a thermostat to keep global temperatures down. You can read about it here if you wish. So what is going on?

Let me start by dismissing the canard that global warming is an invention. Sure, maybe the so-called ‘homogenisation’ of past land and sea temperature data has artificially steepened the warming record since the 1940s. But, for all that, the NOAA satellite data since the end of 1979 shows that the temperature in the sub-troposphere has trended up by about 0.7⁰C between December 1979 and December 2024. As this data has been compiled by Roy Spencer and John Christy (sceptical scientists) at the University of Alamba in Huntsville, we can safely assume it is trustworthy.

So the climate has warmed. Now should come the scientific fun.
Competing theories jostling to best explain the data. No such fun.
Blaming exploitative Western man has proved to be a sacrosanct hypothesis.

Sacrosanctity and science don’t mix. Many past theories propounded by scientific giants have eventually failed the test: Ptolemy’s geocentric theory of the solar system; Aristotle’s theory of gravity, even Newton’s. Yet a tenuous theory of the climate concocted by relative mediocrities, which hasn’t come close to accurately predicting global temperatures, is holy writ. Risible, except that political and celebrity buy-in is undoing progress wherever it results in the replacement of reliable with unreliable energy. Think of Australia as a quintessential case study.

Happily, despite powerful and well-funded forces out to cancel dissenters, maverick scientists keep on stirring the pot. Which brings me back to Prof. Kennedy and his collaborators. Their hypothesis can be found here. In lay terms it goes like this:

The increased concentration of CO2 in the atmosphere since the 1960s has been caused by warming not the reverse. Other things equal, emissions by mankind of CO2 are all absorbed by the land (hence the greening) and by the oceans. Thus, on this account, there is no material net increase of CO2 in the atmosphere from fossil fuel emissions. Ergo, such emissions cannot be the cause of warming. It is true that warming has occurred, and that atmospheric CO2 has risen. The underlying chain of events is as follows.

Warming, perhaps through solar activity, promotes the precipitation of calcium carbonate (limestone) in surface sea water, absorbing CO2 from the atmosphere in the process. In turn, the absorbed CO2, magnified by calcium carbonate precipitation, acidifies surface sea water. The acidification then results in the emission of CO2 into the atmosphere in autumn and winter. This emission of CO2 is greater than the absorption, precisely because of the continuing acidification in the warming water.

In the end we see increased atmospheric CO2 and warming.
It is easy to draw the wrong conclusion. Indeed, the IPCC has done so.

I see the point about Kennedy’s hypothesis being singularly different from other alternative hypotheses. Lindzen’s and Happer’s hypothesis, and Clauser’s, embrace the foundational proposition of the received theory, albeit in muted form. Namely, that man-made CO2 is adding to atmospheric CO2, thereby having a greenhouse effect. Kennedy’s hypothesis does not embrace that proposition.

Whether Kennedy is right (or Lindzen and Happer or Clauser) is by the way. Alternative hypotheses are in the skeptical scientific tradition of searching for theories which better explain the facts than does the received theory. That is particularly important in this case. The received theory is upending life as we know it, while being shielded from rival theories by money, politics and pseudo-religiosity.

The paper by Ivan Kennedy et al. is A Thermal Acid Calcification Cause for Seasonal Oscillations in the Increasing Keeling Curve . Synopsis below with excerpts in italics with my bolds and added images.

Abstract:

Why do atmospheric carbon dioxide levels rise and fall seasonally measured on Mauna Loa? This study explores the thermal acid-calcification (TAC) hypothesis, suggesting that seasonal temperature shifts in surface seawater trigger acid pH-driven CO₂ emissions caused by calcification. Using oceanographic data, we modeled how temperature affects dissolved inorganic carbon including CO₂, bicarbonate, and carbonate.

Our findings reveal that warming waters absorb atmospheric CO2 by promoting calcium carbonate formation, acidifying seawater and boosting CO₂ release to the atmosphere in late autumn and winter, when atmospheric CO₂ becomes highest. The model predicts a net annual CO₂ rise of 2 ppmv, driven by calcification rather than land-based processes. Seasonal pH swings of 0.04 units corroborate this mechanism. The TAC hypothesis indicates that continued ocean warming, not just fossil fuels, contribute to rising CO₂ levels, calling for deeper investigation into marine carbon dynamics.

The Keeling Curve for atmospheric pCO2 in parts per million by volume

Fig. 1. The Keeling curve of atmospheric CO2 partial pressure at 3200 m on Mauna Loa, Hawaii. Data from Dr. Pieter Tans, NOAA/ESRL and Dr.Ralph Keeling, Scripps Institution of Oceanography.CC BY-SA

The very stuff of plant life on Earth in photosynthesis as well as in the structural basis of all living creatures, we are told by the United Nations Intergovernmental Panel on Climate Change (IPCC) (2) that the continuing rise of CO2 in the Keeling curve shown in Figure 1 now threatens global catastrophe from global warming. Such a paradoxical contrast for good and bad lacks credibility, given the longevity of life on Earth.

Transfers of CO2 out of the ocean surface in winter versus that entering in summer

We propose that a quasi-equilibrium exists between a falling pH value in surface water, favoring CO2 emisssion. Falling pH values in the surface water of the oceans have been an enigma, invisible to scientific view until recently after the year 2000. Our logic is supported in our articles (3, 4) where we describe the basis for the thermal acid-calcification (TAC) hypothesis, also using data cited from others. Acidic calcification is thermodynamically favored in warming surface seawater, particularly in northern oceans in spring and summer with shallow mixing zones and higher temperature ranges. This raises the fugacity or potential pressure of CO2 in seawater to its peak value in summer when the pCO2 in air is minimal, causing its forceful emission into air in the next autumn reaching a maximum pCO2 in late winter (Fig. 1, seasonal variation insert).

Fig. 2. Thermal acid-calcification model for seasonal and longer-term generation of the Keeling curve. The Thermal model (3), showed calcification is favored by increase in temperature giving decreasing pH values in summer, reversing in cooler conditions to more alkaline pH in winter. Note that precipitation of CaCO3 in spring to summer removes CO32- that is replaced from HCO3 – with more acidity, provided by absorption of CO2 from air up to October. However, as the pH falls the steady state concentration of [CO2} increases favoring photosynthesis.

Acid calcification is essential for phytoplankton

Any process of strong acidification of surface seawater will raise the concentration of carbon dioxide as [CO2] available to phytoplankton for photosynthesis. Bicarbonate cannot be a direct substrate for photosynthesis although the presence of the enzyme carbonic anhydrase speeds up its interconversion with CO2. Our published modeling analysis confirmed that CaCO3 precipitation is strongly favored by warmer temperatures (Table 1). Indeed, all the reaction equilibria in seawater are displaced to the right in Figure 2 acidifying the water, although the equilibrium between CO2 concentration and pCO2 in air favors a lower concentration [CO2} in water in summer, compared to winter, when it is greatest. Our results even confirmed that the formation of CaCO3 as calcite is predicted to increase in summer as water becomes warmer (Table 1b).

Thus, we can expect more limestone formation in summer if the carbonate concentration reaches a sufficient level, favored by added warming. The decline in average pH values in surface seawater to about 8.05 from pH 8.20 could explain the increased pCO2 in the atmosphere of 140 ppmv since 1800 as a matter of dynamic equilibrium. Caused by calcification, this would require a simultaneous equivalent deposition of limestone as sediment, though only an increase of about 10 μmoles per kg of surface seawater, or a net 1 mg per kg each year. This is a key prediction for experimental testing of the TAC hypothesis.

This fully reversible calcification equation moves towards acidification in summer and reverses to alkalinization in winter. The psi factor is a variable function of the range of seasonal changes in temperature. However, the greatest thermodynamic potential to emit CO2 in seawater by acidification of bicarbonate (HCO3-) is when the pH value is lowest, the conversion of bicarbonate to CO2 generating the greatest difference between CO2 fugacity in seawater and that in air in midsummer in northern hemisphere waters. The seasonal variation near Mauna Loa in atmospheric pCO2 is about 6 ppmv whereas the long term increase in the Keeling curve year by year is one third of this, about 2 ppmv suggesting that in spring and summer the CO2 absorbed in about 2 ppmv, less than that emitted in autumn and winter.

Fig. 5. Rates per square meter in global carbon cycling between land water, the atmosphere, and the ocean, illustrating the pH-acidification hypothesis. Emissions and absorptions shown are average moles per square meter of the Earth, for a mixing ratio of 420 ppmv in 2021 shown in the central column bridging land and ocean. The land acidification values are derived elsewhere (11), assuming photosynthesis is equal to respiration. The terrestrial area of Earth is 1.48×1014 m-2 , the ocean’s area is 3.62×1014 m2 , 5.101 x1014 m2 in total., represented as a mean value in the central air column.

Discussion

Limestone as a product of calcification is regarded as a biogeochemical product, given that phytoplankton and other marine organisms enhance its rate of production, if nutrients are available (3). In particular, the extracellular carbonic anhydrase apparently speeds the reversible dehydration of CO2, forming bicarbonate and hydrated hydrogen ions (H+) controlling pH. This article emphasizes that the reversible dehydration of CO2 in surface seawater allowing transfer between aqueous and gaseous phases is most rate limiting of all, that carbonic anhydrase may even assist in autumn and winter, transferring CO2 to the atmosphere.

More significantly for managing climate change, if fossil fuel emissions are being largely absorbed by sequestration into the ocean surface and by ‘greening’ photosynthesis on land and in the ocean (11), the implications of this aspect of the TAC hypothesis for carbon-zero policies and renewable energy are profound.

The thermal acid-calcification hypothesis predicts that global warming
acidifies the ocean surface by increasing calcification causing
pCO2 to increase, independently of fossil emissions.

Furthermore, this represents a striking illustration of the Le Chatelier principle, the carbon cycle on Earth responding intelligently to changing climate. The hope that carbon dioxide removal as sequestration (14), either biologically, chemically or geologically, by burial after capture, will prove futile.

The uncertainty of the current IPCC paradigm regarding climate change and the role of fossil emissions of CO2 in warming is large, lacking scientific evidence. A plausible alternative hypothesis offered here as the true cause of the increasing Keeling curve needs to be investigated urgently. This new model would still give predictively increasing emissions from the ocean in the complete absence of fossil fuel emissions because the acidification from calcification is purely a function of surface warming, from whatever cause.

The Cooling Also Not Our Fault 2025

Posted on November 17 by Ron Clutz

With the lack of global warming and the steep decline of SSTs the last 2 years, climatists are pivoting to the notion invented by the infamous M. Mann, AKA Mr. Hockey Stick (aiming to erase the Medieval warming period). The reasoning is convoluted, as you might expect given the intent to blame cold weather on global warming. The claim is that burning fossil fuels causes the North Atlantic Current to slow down and bring cold temperatures to the Northern Hemisphere. The video below is an excellent PR piece promoting this science fiction as though it were fact.

Science Facts to Counter Science Fiction

Natural variability has dominated Atlantic Meridional Overturning Circulation since 1900
Mojib Latif et al. published April 2022 Nature Climate Change. Excerpts in italics with my bolds.

Abstract

There is debate about slowing of the Atlantic Meridional Overturning Circulation (AMOC), a key component of the global climate system. Some focus is on the sea surface temperature (SST) slightly cooling in parts of the subpolar North Atlantic despite widespread ocean warming. Atlantic SST is influenced by the AMOC, especially on decadal timescales and beyond. The local cooling could thus reflect AMOC slowing and diminishing heat transport, consistent with climate model responses to rising atmospheric greenhouse gas concentrations.

Here we show from Atlantic SST the prevalence of natural AMOC variability since 1900. This is consistent with historical climate model simulations for 1900–2014 predicting on average AMOC slowing of about 1 Sv at 30° N after 1980, which is within the range of internal multidecadal variability derived from the models’ preindustrial control runs. These results highlight the importance of systematic and sustained in-situ monitoring systems that can detect and attribute with high confidence an anthropogenic AMOC signal.

Main

Global surface warming (global warming hereafter) since the beginning of the twentieth century is unequivocal, and humans are the main cause through the emission of vast amounts of greenhouse gases (GHGs), especially carbon dioxide (CO2)1,2,3. The oceans have stored more than 90% of the heat trapped in the climate system caused by the accumulation of GHGs in the atmosphere, thereby contributing to sea-level rise and leading to more frequent and longer lasting marine heat waves4. Moreover, the oceans have taken up about one third of the total anthropogenic CO2 emissions since the start of industrialization, causing ocean acidification5. Both ocean warming and acidification already have adverse consequences for marine ecosystems6. Some of the global warming impacts, however, unfold slowly in the ocean due to its large thermal and dynamical inertia. Examples are sea-level rise and the response of the Atlantic Meridional Overturning Circulation (AMOC), a three-dimensional system of currents in the Atlantic Ocean with global climatic relevance7,8,9,10.

[Comment: The paragraph above is the obligatory statement of fidelity to the Climatist Creed. All the foundational claims are affirmed with references to prove the authors above reproach, and not to be dismissed as denialists. As further evidence of their embrace of IPCC consensus science, consider the diagrams below.

a, The NAWH SST index (°C), defined as the annual SST anomalies averaged over the region 46° N–62° N and 46° W–20° W. Observations for 1900–2019 from ERSSTv.5 (orange) and Kaplan SST v.2 (yellow), and ensemble-mean SST for 1900–2014 (dark blue line) from the historical simulations with the CMIP6 models and the individual historical simulations (thin grey lines) are shown. b, Same as a but for the NA-SST index (°C), defined as the annual SST anomalies averaged over the region 40° N–60° N and 80° W–0° E. c, Same as a but for the AMO/V (°C) index, defined as the 11-year running mean of the annual SST anomalies averaged over the region 0° N–65° N and 80° W–0° E. The SST indices in a–c are calculated as area-weighted means. d, NAO index (dimensionless) for 1900–2019 (red), defined as the difference in the normalized winter (December–March) sea-level pressure between Lisbon (Portugal) and Stykkisholmur/Reykjavik (Iceland). The blue curve indicates the equivalent CO2 radiative forcing (W m−2) for 1900–2019, which is taken from the Representative Concentration Pathway (RCP) SSP5-8.5 after 2014.

Chart d shows the NAO fluxes compared to a CO2 forcing curve based upon the much criticized RCP 8.5 scenario, which is not “business-as-usual” but rather “business-impossible.” Using it shows the authors bending over backwards to give every chance for confirming the alarming slowdown narrative. The next paragraph gives the entire game away]

Climate models predict substantial AMOC slowing if atmospheric GHG concentrations continue to rise unabatedly1,11,12,13,14. Substantial AMOC slowing would drive major climatic impacts such as shifting rainfall patterns on land15, accelerating regional sea-level rise16,17 and reducing oceanic CO2 uptake. However, it is still unclear as to whether sustained AMOC slowing is underway18,19,20,21,22. Direct ocean-circulation observation in the North Atlantic (NA) is limited9,23,24,25,26,27. Inferences drawn about the AMOC’s history from proxy data28 or indices derived from other variables, which may provide information about the circulation’s variability (for example, sea surface temperature (SST)21,29,30, salinity31 or Labrador Sea convection32), are subject to large uncertainties.

Discussion

Observed SSTs and a large ensemble of historical simulations with state-of-the-art climate models suggest the prevalence of internal AMOC variability since the beginning of the twentieth century. Observations and individual model runs show comparable SST variability in the NAWH region. However, the models’ ensemble-mean signal is much smaller, indicative of the prevalence of internal variability. Further, most of the SST cooling in the subpolar NA, which has been attributed to anthropogenic AMOC slowing21, occurred during 1930–1970, when the radiative forcing did not exhibit a major upward trend. We conclude that the anthropogenic signal in the AMOC cannot be reliably estimated from observed SST. A linear and direct relationship between radiative forcing and AMOC may not exist. Further, the relevant physical processes could be shared across EOF modes, or a mode could represent more than one process.

A relatively stable AMOC and associated northward heat transport during the past decades is also supported by ocean syntheses combining ocean general circulation models and data76,77, hindcasts with ocean general circulation models forced by observed atmospheric boundary conditions78 and instrumental measurements of key AMOC components9,22,79,80,81.

Neither of these datasets suggest major AMOC slowing since 1980, and neither of the AMOC indices from Rahmstorf et al.20 or Caesar et al.21 show an overall AMOC decline since 1980.

Contextual Background

From the Energy MIx Changes in Atlantic Current May Fall Within Natural Variability.

In the February, 2022, edition of the journal Nature Geoscience, researchers at the University of Maryland Center for Environmental Science urged more detailed study of the notoriously complex Atlantic Meridional Overturning Circulation (AMOC). Now, oceanographer Mojib Latif and his team from the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany are repeating that call in a paper just published in the journal Nature Climate Change.

The latest study describes the AMOC as a “three-dimensional system of current in the Atlantic Ocean with global climatic relevance.”

The February study responded to an August 2021 warning from the Potsdam Institute
that the AMOC has become wildly unstable and dangerously weak
due to global warming caused by human activity.

The authors of the latest study affirm that the Earth’s oceans have taken up more than 90% of the accumulated heat and roughly a third of all CO2 emissions since the dawn of the industrial age, leading to clearly measurable and devastating impacts like marine heat waves, sea level rise, and ocean acidification.

But it isn’t easy to confirm that the Atlantic circulation is actually slowing, partly because the ocean possesses such “large thermal and dynamical inertia.”

It is also extremely difficult to directly observe ocean circulation patterns in the North Atlantic, and proxies like sea surface temperature are “subject to large uncertainties,” the scientists say. Based on the available data, the GEOMAR study attributes localized sea surface cooling in the North Atlantic since 1900 to natural AMOC variability—not, as had been hypothesized, to a global heating-induced breakdown in the AMOC’s capacity to transfer heat.

Footnote:

IPCC Global Warming Claims Not Only Wrong, But Impossible

Posted on October 27 by Ron Clutz

Ad Huijser recently published a paper explaining why IPCC claims about global warming are contradicted by observations of our Earth thermal system including a number of internal and external subsytems. The title Global Warming and the “impossible” Radiation Imbalance links to the pdf. This post is a synopsis to present the elements of his research findings, based on the rich detail, math and references found in the document. Excerpts in italics with my bolds and added images. H/T Kenneth Richard and No Tricks Zone.

Abstract

Introduction

Estimating our climate’s thermal capacity CCL

The (near) “steady state” character of current climate change

This analysis strengthens the conclusion that the increase in both N(t) and N0(t) are not a direct consequence of greenhouse gas emissions, but rather of enhanced forcing in the SW-channel.

Ocean Heat Content increase

ERBE measurements of radiative imbalance.

Summary and conclusions

See Also:

Our Atmospheric Heat Engine

About Sea Surface Temperatures

Posted on October 12 by Ron Clutz

Background from NOAA Climate.gov

Q: What’s the temperature of water at the ocean’s surface?
A: Colors on the map show the temperature of water right at the ocean’s surface. The darkest blue shows the coldest water: floating sea ice is usually present in these areas. Lighter shades of blue show temperatures of up to 80°F. White and orange areas show where surface temperatures are higher than 80°F, warm enough to fuel tropical cyclones or hurricanes.

Q: Where do these measurements come from?
A: Satellite instruments measure sea surface temperature—often abbreviated as SST—by checking how much energy comes off the ocean at different wavelengths. Computer programs merge sea surface temperatures from ships and buoys with the satellite data, and incorporate information from maps of sea ice. To produce the daily maps, programs invoke mathematical filters to combine and smooth data from all three sources.

Q: Why do these data matter?
A: While heat energy is stored and mixed throughout the depth of the ocean, the temperature of water right at the sea’s surface—where the ocean is in direct contact with the atmosphere—plays a significant role in weather and short-term climate. Where sea surface temperatures are high, relatively large amounts of heat energy and moisture enter the atmosphere, sometimes producing powerful, drenching storms downwind. Conversely, lower sea surface temperatures mean less evaporation. Global patterns of sea surface temperatures are an important factor for weather forecasts and climate outlooks.

Q: How did you produce these snapshots?
A: Data Snapshots are derivatives of existing data products: to meet the needs of a broad audience, we present the source data in a simplified visual style. NOAA’s Climate Data Records Program produces the Opitimum Interpolated Sea Surface Temperature files. To produce our images, we run a set of scripts that access the source files, re-project them into desired projections at various sizes, and output them with a custom color bar.

With the federal government shutdown, dataset updates are uncertain, but OISST is current and shows how presently the ocean is cooling down from it’s 2024 high temperatures.

Note: Daily SST Ocean Temperature Graphic, 1982-2025

Use the options below to generate graphics of daily sea surface temperatures since 1982 using data from NOAA’s Optimum Interpolation Sea Surface Temperature (OISST) v2.1 dataset. [The chart above defines Global as 60°N to 60°S.] These graphics will update daily, or as data becomes available on the Climate Reanalyzer website. Note the most recent two weeks of data are considered preliminary. Specific information about the data can be found here.

My Comment:

The chart shows how 2025 is tracking ~half a degree F cooler than 2024. That may not seem significant, except that the ocean covers 71% of the Earth’s surface, and any SST warming is reported in numbers of zettajoules. This is explained at the EPA website Climate Change Indicators: Ocean Heat:

The top 700 meters of the ocean contain 63% of the ocean’s heat content. The data shows that ocean layer has warmed about a zettajoule (1×10^22 joules) yearly since 1990.

For reference, an increase of 1 unit on this graph (1 × 10^22 joules) is equal to approximately 17 times the total amount of energy used by all the people on Earth in a year (based on a total global energy supply of 606 exajoules in the year 2019, which equates to 6.06 × 10^20 joules).

It appears that presently we may be about to lose that amount of energy through oceanic cooling. And the sun could be to blame:

Scare du jour Marine Heat Waves

Posted on October 8 by Ron Clutz

If you watch legacy media, you must also be wondering after seeing all the current headlines about Marine Heat Waves raising the ocean to its boiling point.

Ocean heatwaves are breaking Earth’s hidden climate engine, Science Daily

The Pacific Ocean is overheated, making fall feel like summer, CBC

The ‘blob’ is back — except this time it stretches across the entire north Pacific, CNN

Record marine heatwaves may signal a permanent shift in the oceans, New Scientist

Global warming drives a threefold increase in persistence and 1 °C rise in intensity of marine heatwaves, PNAS

Etc., etc. etc.

The last one is the paper driving this recent clamor over Ocean SSTs Marcos et al. 2025 From the abstract:

We determine that global warming is responsible for nearly half of these extreme events and that, on a global average, it has led to a three-fold increase in the number of days per year that the oceans experience extreme surface heat conditions. We also show that global warming is responsible for an increase of 1 °C in the maximum intensity of the events. Our findings highlight the detrimental role that human-induced global warming plays on marine heatwaves. This study supports the need for mitigation and adaptation strategies to address these threats to marine ecosystems.

The coordinated media reports are exposed by all of them containing virtually the same claim:

As climate change causes our planet to warm, marine heatwaves are
becoming more frequent, more intense, and longer lasting.

Animation shows locations of moderate to severe MHWs mid-month 2025 January to October. A marine heatwave is defined as one where the measured temperature is within 10% of the maximum values observed (i.e., above the Threshold (90th quantile) , for at least 5 consecutive days. For this, the intensity is compared to the difference between the climatological mean and the 90th percentile value (threshold). A marine heatwave intensity between 1 and 2 times this difference corresponds to a heatwave of moderate category; between 2 and 3 times, to a strong category; between 3 and 4 times, to a severe category; and a difference greater than 4 times corresponds to an extreme category.

First some background context on the phenomena (in italics with my bolds).

Background from perplexity.ai How Do Warm and Cool Ocean Blobs Circulate?

Warm and cool ocean blobs circulate through distinct oceanic and atmospheric processes, often linked to major currents and atmospheric patterns.

Warm ocean blobs, such as the “warm blob” in the northeast Pacific, form due to atmospheric circulation changes triggered by factors like Arctic warming. This leads to a high-pressure system over the region, weakening westerly winds and reducing ocean heat loss, causing surface waters to warm and creating persistent warm anomalies. The formation of these warm blobs involves a feedback loop between weakened winds, reduced ocean-atmosphere heat exchange, and ocean circulation, which retains heat in the mixed layer of the ocean.

Cool ocean blobs, like the North Atlantic “cold blob,” are influenced by weakening of the Atlantic Meridional Overturning Circulation (AMOC). This circulation moves warm, salty water northward, which cools, sinks, and then the cooler deep water travels southward in a conveyor-belt style flow. The cold blob forms when excess freshwater from ice melt dilutes the salty water, reducing its density and sinking ability, weakening this circulation and causing cooler surface water to persist. This cooling also affects the atmosphere by reducing water vapor, which decreases greenhouse effect locally and amplifies the cold anomaly, creating a coupled ocean-atmosphere feedback loop.

In summary, warm and cool ocean blobs circulate through a combination of ocean current dynamics and atmospheric interactions. Warm blobs form where atmospheric changes reduce ocean heat loss and circulation shifts retain heat, while cool blobs occur where circulation weakens, allowing cooler, less dense waters to persist and affect atmospheric conditions as well.

Then a summary of the issues undermining the alarmists’ claim.

From perplexity.ai What are reasons to doubt climate change is increasing marine heatwaves?

There are several reasons to doubt that climate change is definitively increasing the frequency, intensity, duration, and spatial extent of marine heatwaves, based on some ongoing scientific debates and uncertainties.

Natural Variability and Other Factors

♦ Marine heatwaves are influenced by natural climate variability, such as El Niño, Pacific Decadal Oscillation (PDO), and other oceanic and atmospheric processes. These phenomena can cause fluctuations in sea surface temperatures independent of long-term climate change, leading to periods of warmer ocean conditions that may be mistaken for climate-driven trends.

♦ Some studies emphasize the role of internal ocean variability, which can cause significant short-term temperature anomalies without requiring a direct link to anthropogenic climate change.

Complexity of Attribution

♦ The attribution of marine heatwave trends specifically to climate change involves complex modeling and statistical analysis, which can have uncertainties. Certain models suggest that long-term temperature increases are the primary driver, but the contribution of natural variability remains significant and sometimes difficult to separate clearly from climate signals.

♦ Regional differences and localized oceanic processes can obscure the global patterns, leading some scientists to argue that not all observed phenomena are directly attributable to climate change, particularly in areas with strong natural variability.

Limitations of Climate Models

♦ Climate models predicting future marine heatwave conditions depend heavily on assumptions about greenhouse gas emissions and other factors. These models often have limitations in resolution and in capturing small-scale processes, which could lead to overestimations or underestimations of climate change impacts.

Data Gaps and Uncertainties

♦ Although current observations show increasing trends in marine heatwaves, data gaps exist, especially in remote or deep-sea regions, making comprehensive global assessments challenging. These gaps contribute to uncertainty regarding the full extent and causality of observed changes.

♦ The precise long-term ecological impacts and possible adaptation or resilience mechanisms of marine ecosystems also remain uncertain, complicating the understanding of climate change’s role versus natural variability.

Summary

While a considerable body of evidence supports the role of climate change in increasing marine heatwaves, skepticism persists due to the influence of natural variability, model limitations, regional differences, and data gaps. These factors suggest that attribution is complex, and ongoing research continues to refine our understanding of the relative contributions of human influences and natural climate fluctuations.

Finally, a discussion of a specific example revealing flawed methods supposedly connecting CO2 emissions to marine heatwaves.

Much Ado About Marine Heat Waves

The promotion of this scare was published in 2022 at Nature by Barkhordarian et al. Recent marine heatwaves in the North Pacific warming pool can be attributed to rising atmospheric levels of greenhouse gases. This post will unpack the reasons to distrust this paper and its claims. First the Abstract of the subject and their declared findings in italics with my bolds.

Abstract

Over the last decade, the northeast Pacific experienced marine heatwaves that caused devastating marine ecological impacts with socioeconomic implications. Here we use two different attribution methods and show that forcing by elevated greenhouse gases levels has virtually certainly caused the multi-year persistent 2019–2021 marine heatwave. There is less than 1% chance that the 2019–2021 event with ~3 years duration and 1.6 ∘C intensity could have happened in the absence of greenhouse gases forcing. We further discover that the recent marine heatwaves are co-located with a systematically-forced outstanding warming pool, which we attribute to forcing by elevated greenhouse gases levels and the recent industrial aerosol-load decrease. The here-detected Pacific long-term warming pool is associated with a strengthening ridge of high-pressure system, which has recently emerged from the natural variability of climate system, indicating that they will provide favorable conditions over the northeast Pacific for even more severe marine heatwave events in the future.

Background on Ocean Warm Pools

Wang and Enfield study is The Tropical Western Hemisphere Warm Pool Abstract in italics with my bolds.

Abstract

The Western Hemisphere warm pool (WHWP) of water warmer than 28.5°C extends from the eastern North Pacific to the Gulf of Mexico and the Caribbean, and at its peak, overlaps with the tropical North Atlantic. It has a large seasonal cycle and its interannual fluctuations of area and intensity are significant. Surface heat fluxes warm the WHWP through the boreal spring to an annual maximum of SST and areal extent in the late summer/early fall, associated with eastern North Pacific and Atlantic hurricane activities and rainfall from northern South America to the southern tier of the United States. SST and area anomalies occur at high temperatures where small changes can have a large impact on tropical convection. Observations suggest that a positive ocean-atmosphere feedback operating through longwave radiation and associated cloudiness is responsible for the WHWP SST anomalies. Associated with an increase in SST anomalies is a decrease in atmospheric sea level pressure.

Chou and Chou published On the Regulation of the Pacific Warm Pool Temperature:

Abstract

Analyses of data on clouds, winds, and surface heat fluxes show that the transient behavior of basin-wide large-scale circulation has a significant influence on the warm pool sea surface temperature (SST). Trade winds converge to regions of the highest SST in the equatorial western Pacific. The reduced evaporative cooling due to weakened winds exceeds the reduced solar heating due to enhanced cloudiness. The result is a maximum surface heating in the strong convective and high SST regions. The maximum surface heating in strong convective regions is interrupted by transient atmospheric and oceanic circulation. Regions of high SST and low-level convergence follow the Sun. As the Sun moves away from a convective region, the strong trade winds set in, and the evaporative cooling enhances, resulting in a net cooling of the surface. We conclude that the evaporative cooling associated with the seasonal and interannual variations of trade winds is one of the major factors that modulate the SST distribution of the Pacific warm pool.

Comment:

So these are but two examples of oceanographic studies describing natural factors driving the rise and fall of Pacific warm pools. Yet the Nature paper claims rising CO2 from fossil fuels is the causal factor, waving away natural processes. Skeptical responses were already lodged upon the first incidence of the North Pacific marine heat wave, the “Blob” much discussed by west coast US meteorologists. One of the most outspoken against the global warming attributionists has been Cliff Mass of Seattle and University of Washington. Writing in 2014 and 2015, he observed the rise and fall of the warming blob and then posted a critique of attribution attempts at his blog. For example, Media Miscommunication about the Blob. Excerpts in italics with my bolds.

Blob Media Misinformation

One of the most depressing things for scientists is to see the media misinform the public about an important issue.

During the past few days, an unfortunate example occurred regarding the warm water pool that formed over a year ago in the middle of the north Pacific, a.k.a., the blob. Let me show how this communication failure occurred, with various media outlets messed things up in various ways.

The stimulant for the nationwide coverage of the Blob was a very nice paper published by Nick Bond (UW scientist and State Climatologist), Meghan Cronin, Howard Freeland, and Nathan Mantua in Geophysical Research Letters.

This publication described the origin of the Blob, showing that it was the result of persistent ridging (high pressure) over the Pacific. The high pressure, and associated light winds, resulted in less vertical mixing of the upper layer of the ocean; with less mixing of subsurface cold water to the surface. Furthermore, the high pressure reduced horizontal movement of colder water from the north. Straightforward and convincing work.

The inaccurate press release then led to a media frenzy, with the story going viral. And unfortunately, many of the media got it wrong.

There were two failure modes. In one, the headline was wrong, but the internal story was correct. . . In the second failure mode, the story itself was essentially flawed, with most claiming that the Blob off of western North America was the cause of the anomalous circulation (big ridge over West Coast, trough over the eastern U.S.). (The truth: the Blob was the RESULT of the anomalous circulations.) That the Blob CAUSED the California drought or the cold wave in the eastern U.S. These deceptive stories were found in major outlets around the country, including the Washington Post, NBC News, and others.

Blob Returns, Attribution Misinformation

When the Blob returned 2020-2021, Cliff Mass had cause to again lament how the public is misled. This time misdirection instigated by activist scientists using flawed methods. His post Miscommunication in Recent Climate Attribution Studies. Excerpts in italics with my bolds.

This attribution report, and most media stories that covered it, suggested a central role for global warming for the heatwave. As demonstrated in my previous blog, their narrative simply does not hold up to careful examination.

This blog will explain why their basic framing and approach is problematic, leading readers (and most of the media) to incorrect conclusions.

For the heatwave, the attribution folks only examine the statistics of temperatures hitting the record highs (108F in Seattle), but avoid looking at the statistics of temperature exceeding 100F, or even the record highs (like 103F in Seattle). There is a reason they don’t do that. It would tell a dramatically different (and less persuasive) story.

In the attribution studies, the main technology for determining changed odds of extreme weather is to use global climate models. First, they run the models with greenhouse gas forcing (which produces more extreme precipitation and temperature), and then they run the models again without increased greenhouse gases concentrations. By comparing the statistics of the two sets of simulations, they attempt to determine how the odds of extreme precipitation or temperature change.

Unfortunately, there are serious flaws in their approach: climate models fail to produce sufficient natural variability (they underplay the black swans) and their global climate models don’t have enough resolution to correctly simulate critical intense, local precipitation features (from mountain enhancement to thunderstorms). On top of that, they generally use unrealistic greenhouse gas emissions in their models (too much, often using the RCP8.5 extreme emissions scenario) And there is more, but you get the message. ( I am weather/climate modeler, by the way, and know the model deficiencies intimately.)

Vaunted Fingerprinting Attribution Is Statistically Unsound

From Barkhordarian et al.

Unlike previous studies which have focused on linking the SST patterns in the North Pacific to changes in the oceanic circulation and the extratropical/tropical teleconnections2,12,17,18,20,24,26, we here perform two different statistical attribution methodologies in order to identify the human fingerprint in Northeast Pacific SST changes both on multidecadal timescale (changes of mean SST) and on extreme SST events on daily timescale (Marine Heatwaves). Evidence that anthropogenic forcing has altered the base state (long-term changes of mean SST) over the northeast Pacific, which is characterized by strong low-frequency SST fluctuations, would increase confidence in the attribution of MHWs27, since rising mean SST is the dominant driver of increasing MHW frequency and intensity, outweighing changes due to temperature variability1,2.

In this study, we provide a quantitative assessment of whether GHG forcing, the main component of anthropogenic forcings, was necessary for the North Pacific high-impact MHWs (the Blob-like SST anomalies) to occur, and whether it is a sufficient cause for such events to continue to repeatedly occur in the future. With these purposes, we use two high-resolution observed SST datasets, along with harnessing two initial-condition large ensembles of coupled general circulation models (CESM1-LE28,29 with 35 members, and MPI-GE30 with 100 members). These large ensembles can provide better estimates of an individual model’s internal variability and response to external forcing31,32, and facilitate the explicit consideration of stochastic uncertainty in attribution results33. We also use multiple single-forcing experiments from the Detection and Attribution Model Intercomparision Project (DAMIP34) component of Coupled Model Intercomparison Project phase 6 (CMIP635).

From Barkhordarian et al. References

The IPCC’s attribution methodology is fundamentally flawed

The central paper underpinning the attribution analysis was assessed and found unreliable by statistician Ross McKitrick’s published evaluation. Excerpts in italics with my bolds.

One day after the IPCC released the AR6 I published a paper in Climate Dynamics showing that their “Optimal Fingerprinting” methodology on which they have long relied for attributing climate change to greenhouse gases is seriously flawed and its results are unreliable and largely meaningless. Some of the errors would be obvious to anyone trained in regression analysis, and the fact that they went unnoticed for 20 years despite the method being so heavily used does not reflect well on climatology as an empirical discipline.

My paper is a critique of “Checking for model consistency in optimal fingerprinting” by Myles Allen and Simon Tett, which was published in Climate Dynamics in 1999 and to which I refer as AT99. Their attribution methodology was instantly embraced and promoted by the IPCC in the 2001 Third Assessment Report (coincident with their embrace and promotion of the Mann hockey stick). The IPCC promotion continues today: see AR6 Section 3.2.1. It has been used in dozens and possibly hundreds of studies over the years. Wherever you begin in the Optimal Fingerprinting literature (example), all paths lead back to AT99, often via Allen and Stott (2003). So its errors and deficiencies matter acutely.

Abstract

Allen and Tett (1999, herein AT99) introduced a Generalized Least Squares (GLS) regression methodology for decomposing patterns of climate change for attribution purposes and proposed the “Residual Consistency Test” (RCT) to check the GLS specification. Their methodology has been widely used and highly influential ever since, in part because subsequent authors have relied upon their claim that their GLS model satisfies the conditions of the Gauss-Markov (GM) Theorem, thereby yielding unbiased and efficient estimators.

But AT99:

stated the GM Theorem incorrectly, omitting a critical condition altogether,
their GLS method cannot satisfy the GM conditions, and
their variance estimator is inconsistent by construction.
Additionally, they did not formally state the null hypothesis of the RCT nor
identify which of the GM conditions it tests, nor
did they prove its distribution and critical values, rendering it uninformative as a specification test.

The continuing influence of AT99 two decades later means these issues should be corrected. I identify 6 conditions needing to be shown for the AT99 method to be valid.”

In Conclusion, McKitrick:

One point I make is that the assumption that an estimator of C provides a valid estimate of the error covariances means the AT99 method cannot be used to test a null hypothesis that greenhouse gases have no effect on the climate. Why not? Because an elementary principle of hypothesis testing is that the distribution of a test statistic under the assumption that the null hypothesis is true cannot be conditional on the null hypothesis being false. The use of a climate model to generate the homoscedasticity weights requires the researcher to assume the weights are a true representation of climate processes and dynamics.

The climate model embeds the assumption that
greenhouse gases have a significant climate impact.

Or, equivalently, that natural processes alone cannot generate a large class of observed events in the climate, whereas greenhouse gases can. It is therefore not possible to use the climate model-generated weights to construct a test of the assumption that natural processes alone could generate the class of observed events in the climate.

More Evidence Temperatures Drive CO2 Levels, Not the Reverse

Posted on August 30 by Ron Clutz

Robbins, 2025 Figure 2: Global tropic SSTs overlaid onto monthly atmospheric CO2 increases (Mauna Loa)

Kenneth Richard posted a No Tricks Zone article: Another New Study Suggests Most – 80% – Of The Modern CO2 Increase Has Been Natural. Excerpts in italics with my bolds and added images.

CO2 concentration increases are not the cause of rising temperature,
but an effect of rising temperature.

The 2025 paper by Bernard Robbins is Atmospheric CO2: Exploring the Role of Sea Surface Temperatures and the Influence of Anthropogenic CO2. Excerpts in italics with my bolds and added images.

Abstract

Close examination of the small perturbations within the atmospheric CO2 trend, as measured at Mauna Loa, reveals a strong correlation with variations in sea surface temperatures (SSTs), most notably with those in the tropics. The temperature-dependent process of CO2 degassing and absorption via sea surfaces is well-documented, and changes in SSTs will also coincide with changes in terrestrial temperatures, and temperature-dependent changes in the marine and terrestrial biospheres with their associated carbon cycles.

Using SST and Mauna Loa datasets, three methods of analysis are presented that seek to identify and estimate the anthropogenic and, by default, natural components of recent increases in atmospheric CO2, an assumption being that changes in SSTs coincide with changes in nature’s influence, as a whole, on atmospheric CO2 levels. The findings of the analyses suggest that an anthropogenic component is likely to be around 20 %, or less, of the total increase since the start of the industrial revolution.

The inference is that around 80 % or more of those increases are of natural origin, and indeed the findings suggest that nature is continually working to maintain an atmospheric/surface CO2 balance, which is itself dependent on temperature. A further pointer to this balance may come from chemical measurements that indicate a brief peak in atmospheric CO2 levels centred around the 1940s, and that coincided with a peak in global SSTs.

Source: The phase relation between atmospheric carbon dioxide and global temperature OleHumlum, KjellStordahl, Jan-ErikSolheim.

Introduction

Research into the influence SSTs have on changes in atmospheric CO2 includes the work by Humlum et al. (2013). When examining phase relationships, they found a maximum correlation for changes in atmospheric CO2 lagging 11-12 months behind those of global SSTs [1]. A paper by the late Fred Goldberg (2008) noted their correlation by examining El Niño events [2]. He also considered Henry’s law [3] in relation to SSTs, i.e. a temperature-dependent equilibrium between atmospheric CO2 and its solubility in seawater. Spencer (2008) also noted similarities between surface temperature variations with changes in atmospheric CO2 [4].

For the oceans specifically, areas of surface CO2 absorption and degassing are shown in maps provided by NOAA [5] and ESA [6] for example. These maps show that colder sea surfaces towards the poles are net absorbers of CO2 whilst the warmer surface waters of the tropics are net emitters. An analogy often cited is the greater ability of carbonated drinks to retain CO2 at cooler temperatures; this ability drops as the drinks get warmer.

Figure 1: Deseasonalised atmospheric CO2 data (Mauna Loa).

A strong correlation between changes in atmospheric CO2 and SSTs can be readily discerned from the relevant datasets. To illustrate, the upper graph in Fig. 1 plots atmospheric CO2 in parts per million (ppm) as measured at Mauna Loa, Hawaii, since 1982. The data [7] has been ‘deseason-alised’ by NOAA to remove natural annual CO2 cycles.

The similarity between the two traces is striking: short-term fluctuations in CO2 readings at Mauna Loa appear particularly sensitive to tropic conditions (if tropic SSTs are substituted for global SSTs in Fig. 2, the correlation is less strong). Warm tropical seas, with surface temperatures typically around 25-30 oC, cover almost one third of the earth’s surface. The most prominent peaks in the figure coincide with strong El Niño events. Taken at face value, and ignoring any influence from anthropogenic emissions, Fig. 2 suggests that if the tropic SST anomaly dropped to around -1 oC (with related drops globally) then the concentration of CO2 in the atmosphere, as measured at Mauna Loa, would level off.

Robbins, 2025 Figure 2: Global tropic SSTs overlaid onto monthly atmospheric CO2 increases (Mauna Loa)

An important point is that changes in SSTs will coincide with those of terrestrial temperatures, temperature-dependent changes to both terrestrial and marine carbon cycles and, taking into consideration the research by Humlum et al. (2013) who found that changes in atmospheric CO2 followed changes in SSTs, an assumption in the work presented here is that nature’s influence on atmospheric CO2 levels, as a whole, follows on from changes in SSTs.

Discussion

The techniques used in Analyses 1 and 2, aimed at discerning and estimating the human contribution to recent increases in atmospheric CO2, are based on processing of monthly data from both SST and atmospheric CO2 datasets. Using the technique described in Analysis 1, no contribution from human emissions to the measured increases in atmospheric CO2, since 1995, was discerned. Given an approximate 60 % increase in annual human emissions since 1995 this suggests, by itself, that any human contribution to the measured increases is likely to be relatively small compared to nature’s contribution.

For the technique described in Analysis 2, a figure of ~27 ppm was estimated for a possible human contribution out of a total increase of 143 ppm since 1850, equating to around 19 % of the total increase in atmospheric CO2 since the start of the industrial revolution. Thus the results of these two analyses, taken together, suggest that nature appears to account for around 80 % or more of increases in atmospheric CO2 since 1995.

The technique described in Analysis 3 examines the relationship between longer-term trends in SST datasets and atmospheric CO2 measurements. This data analysis goes as far back as the late 1950s, when the ongoing acquisition of atmospheric CO2 measurements began at Mauna Loa. The resulting three graphs show an apparent almost-linear long-term relationship between SSTs and atmospheric CO2. Linear trend lines fitted to these graphs produce gradients of between ~120 and ~145 ppm/ 0C for the three SST datasets examined.

Figure 15: Atmospheric CO2 as a function of global SST trend since 1958

As for anthropogenic CO2, published figures (e.g. GCB data) suggest a roughly linear relationship between cumulative anthropogenic emissions as a function of time, and atmospheric CO2 measurements from Mauna Loa. If it’s reasoned that this mostly accounts for the linear trends as calculated in Analysis 3, this reasoning would not fit with the findings of the first two analysis methods that suggest 80 % or more of recent atmospheric CO2 increases are of natural origin.

Conclusions

Analyses of SST and atmospheric CO2 data, acquired since 1995, produce an estimated atmospheric CO2 increase, possibly attributed to human emissions, of around 20 %, or less, of the total increase since the industrial revolution, thus inferring that around 80 % or more of the increase is of natural origin.

Further data examination points to an almost linear longer-term relationship between SSTs and atmospheric CO2 since at least the late 1950s, and is suggestive of nature working to maintain a temperature-dependent atmosphere/surface CO2 balance. Recent historical evidence of such a balance may come from chemical measurements that indicate a brief peak in atmospheric CO2 levels centred around the 1940s, and that coincided with a peak in global SSTs.

Human emissions of CO2 are about 1/20-th of the natural turnover, and the findings of the analyses presented here suggest that this relatively-small human contribution is being readily incorporated into nature’s carbon cycles as they continually adjust to our constantly-changing climate.

As for surface temperatures, the research by Humlum et al. concluded that changes in atmospheric temperature are an ‘effect’ of changes in SSTs and not a ‘cause’ as some might advocate. And Humlum’s ‘take home’ message from a recent presentation was:

‘What controls the ocean surface temperature, controls the global climate’ [33]. He suggests the sun would be a good candidate, modulated with the cloud cover.

Wind And Solar Power Both Capricious and Costly

Posted on May 2 by Ron Clutz

Bill Ponton reminds us that in addition to being fickle, renewables are also costly, in his American Thinker article What are the merits of renewables? Excerpts in italics with my bolds and added images.

The Spanish blackout made us all aware of how unstable the grid can get when renewables are in the driver’s seat, but one should also not forget that they don’t come cheaply. The idea of getting free energy from wind and solar is inaccurate. Man must build machines to extract energy from nature and those machines, windmills and solar panels, are expensive.

Usually, proponents of renewables point to the fact that once the windmills and solar panels are installed, there is no added cost for fuel. That’s true, but there is more to the story. The capital cost of capacity for onshore wind, solar, and natural gas is $1.7 /MW, $1.3/MW, and $1.2/MW, respectively, a difference, but maybe not what one would call significant.

However, there is a gross disparity between capacity factors for each with 31% for wind, 20% for solar, and 60% for natural gas, as evidenced by the figures from Texas grid operator, ERCOT, in 2023. The capacity factor is a measure of how effectively a power plant or energy-producing system is operating compared to its maximum potential output over a specific period (Capacity Factor = Actual Output / Maximum Possible Output).

It should be said that a capacity factor of 60% for natural gas is what one would expect if the operator were only dependent upon natural gas. The current situation where natural gas generation is used to backup solar and wind generation drives the capacity factor for natural gas generation down to 36%.

With these lower capacity factors, one gets a cost multiple
of over 1.5 times greater to operate a mixed energy system
versus a system with just natural gas.

My calculations are here for all to examine. Another way to look at it is that the price of natural gas would have to go up by a factor of five (x5) to make the combined system with wind, solar, and natural gas cost competitive against a system with natural gas alone. Although Texas has a lot to brag about, its use of multiple energy sources to power its grid is not one of them. Why would one expect any other result from a scheme that requires massive subsidies, mandates, and tax breaks to even exist?

So, if renewables are unreliable and expensive, who finds them appealing? The answer is folks that are so guilt-ridden about their role in a supposed climate catastrophe that they will grab on to any scheme that offers them absolution, whether it has merit or not.

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