by Nicola Scafetta
My new book is now published:
The Frontier of Climate Science: Solar Variability, Natural Cycles and Model Uncertainty
For more than twenty years, my research has explored the interplay between climate dynamics, solar variability, and complex systems. During this time, I have watched the climate debate become increasingly polarized, often reduced to a narrow narrative that leaves little room for uncertainty or alternative interpretations.
My new book, The Frontier of Climate Science, was written to address this gap. It is not intended as a counter‑dogma, nor as a political statement. It is a scientific journey — one that examines what we know, what we assume, and what remains unresolved about the climate system.
In this article, I share some of the motivations behind the book and highlight a few of its central themes.
Over the years, I have become increasingly convinced that the climate system cannot be fully understood through a single explanatory lens. The prevailing attribution framework is the one currently advocated by the Intergovernmental Panel on Climate Change (IPCC). It assigns nearly all post‑1850 warming to anthropogenic forcings. However, this assessment rests on computer global climate models (GCMs) that, while sophisticated, still struggle with fundamental aspects of natural variability.
Book synopsis
Book Synopsis
How well do we truly understand Earth’s climate? What natural forces remain beyond our grasp? Is Net Zero the only viable path forward?
The Frontier of Climate Science explores climate dynamics through physics, complex systems, and astronomy, synthesizing several decades of peer-reviewed research.
The book critically reviews the scientific foundations of modern climate theory, the evolution of IPCC assessments, and the limits of global climate models (GCMs) when confronted with observations. It investigates natural variability across multiple timescales, including oceanic oscillations, solar variability, and astronomical cycles driving both solar and climate variability, integrating satellite data, paleoclimate reconstructions, and empirical modeling approaches.
From this evidence emerges a balanced view of climate risk, favoring pragmatic adaptation over narrowly defined policy pathways such as Net Zero. Rich in insights and analytical approaches, the book helps readers understand climate variability, assess risks, think critically, and explore key open questions in climate science.
Endorsed by the International Association for Gondwana Research (IAGR) and by the “Centro di Ricerca Previsione, Prevenzione e Controllo dei Rischi Geologici” (CERI), Sapienza University of Rome.
From the Foreword by Prof. M. Santosh:
“This book … offers an excellent window into the deep realms of climatology, complex systems physics, and astronomy in addressing three major aspects: (1) how well do we truly understand Earth’s climate? (2) what natural forces remain beyond our grasp? (3) is Net-Zero the only viable path forward?“
“From an authoritative analysis, the author formulates insightful perspectives that demystify the exclusive attribution of global warming in the last century to human activities, and places more importance on the dynamic interplay of terrestrial and cosmic forces.“
“This work is an excellent window into climatology as a dynamic science, and calls for adaptive strategies grounded in economic sustainability and social equity to address climate change issues.“
From the Foreword by Prof. Alberto Prestininzi:
“In The Frontier of Climate Science, Scafetta constructs a theoretical and didactic journey that guides the reader through the multiple dimensions of the climate system. The book is conceived as a critical dialogue in which the processes that govern Earth’s climate – many of which remain poorly understood or underestimated – are examined in depth.“
“The goal is to distinguish facts from rhetoric, restoring to science its role as a pluralistic, iterative, and non-dogmatic inquiry.“
“Scafetta’s work fits fully within this long trajectory of scientific inquiry, but with a theoretical and systemic perspective… The Frontier of Climate Science is thus a work that invites reflection, verification, and debate.“
From the Foreword by Prof. Judith Curry:
“The seminal contribution of The Frontier of Climate Science is a new scientific paradigm that provides a broader interpretive framework capable of resolving the inconsistencies of the current anthropogenic climate change model.“
“Solar variability and its role in climate change remain among the most profound and unresolved issues in contemporary climate science. Scafetta makes a compelling argument that it is time to bring the Sun back to the center of climate discourse.“
“A healthy scientific culture embraces pluralism, methodological rigor, and open dialogue. Only through this lens can climate science remain credible, adaptive, and truly informative… Scafetta’s framework offers a valuable opportunity for engagement.“
1. Why I wrote this book
My goal was to bring these threads together into a coherent, interdisciplinary perspective — one that reflects not only the breadth of the scientific debate, but also the many dimensions of the problem that I have personally explored in my own scientific publications over the past two decades, from solar variability to climate oscillations, from data biases to empirical modeling.
2. Climate as a multi‑scale, oscillatory system
One of the most striking features of Earth’s climate history is its rhythmic natural structure. Throughout the Holocene, we observe:
- multidecadal oscillations (~60 years),
- centennial fluctuations,
- millennial‑scale cycles such as the Eddy cycle,
- and the Hallstatt–Bray cycle.
These patterns appear in ice cores, marine sediments, tree rings, and historical documents. They also correlate with solar and astronomical proxies. These cycles are not speculative; they are among the most robust features of paleoclimate research.
Yet current GCMs do not reproduce these oscillations with the correct amplitude or timing.
This is not a minor detail. If models cannot capture the natural background variability of the climate system, then attribution regarding the global warming from 1850–1900 to the present becomes inherently uncertain, because any unmodeled natural contribution to the warming (for example due to solar activity increase during the same period) necessarily reduces the fraction of warming that can be confidently assigned to anthropogenic forcings. And if the anthropogenic contribution to past warming is smaller than assumed, then its contribution to future warming — and therefore the associated climate risk — must also be proportionally reduced.
3. Observational datasets: essential but imperfect
Another motivation for writing the book was the growing divergence between different observational datasets.
Surface temperature records are indispensable, but they are also affected by:
- urbanization and land‑use changes,
- station relocations,
- instrumentation shifts,
- homogenization algorithms that may introduce artificial convergence.
Satellite datasets, by contrast, show 20–30% less warming since 1980, particularly over Northern Hemisphere land areas. Rural‑only station reconstructions also reveal weaker secular warming.
These discrepancies do not undermine the reality of global warming, but they do expand the uncertainty range. A mature scientific field should acknowledge this openly.
4. The Sun: a more complex actor than often assumed
My work on solar variability began more than two decades ago, partly through my involvement with NASA–JPL’s ACRIM experiment, which was designed to measure total solar irradiance from space. Over time, it became increasingly clear to me that the Sun’s influence on climate is significant, but that a proper assessment requires addressing the long‑standing controversies surrounding solar variability on timescales longer than the 11‑year solar cycle — controversies that remain central to understanding the natural contribution to modern climate change.
The book reviews:
- the ACRIM–PMOD controversy,
- spectral solar variability,
- magnetic modulation of cosmic rays,
- cloud‑related mechanisms,
- and the possible role of planetary harmonics.
The point is not that “the Sun explains everything.” Rather, it is that current models incorporate an overly simplified representation of solar variability, which may help explain why they attribute essentially zero post‑1850 warming to solar changes.
This assumption deserves reexamination.
Contemporary hypotheses that secular and multimillennial solar activity has changed only minimally inevitably fail to account for the strong correlations observed throughout the Holocene between solar variability and documented climatic shifts. If long‑term solar variability is assumed to be negligible, these empirical relationships become scientifically inexplicable, underscoring the need to revisit the underlying assumptions.
5. The “hot model” problem and climate sensitivity
A recurring theme in recent literature is the tendency of many CMIP6 models to run too hot. They often:
- overestimate warming since 1980,
- fail to reproduce the 2000–2014 pause,
- miss the quasi‑60‑year oscillation,
- and predict a tropical tropospheric hot spot that remains elusive.
These issues directly affect estimates of equilibrium climate sensitivity (ECS).
My empirical analyses suggest:
- ECS ≈ 2.2 ± 0.5 °C,
- or ≈ 1.1 ± 0.4 °C if long‑term solar variability is larger and additional mechanisms are active.
A lower ECS implies more moderate future warming and reduces the need for extreme mitigation pathways.
6. Policy implications: a call for realism, not complacency
The book is not a political treatise. But scientific conclusions inevitably have policy implications.
If natural variability plays a larger role than currently assumed, if observational datasets contain unresolved biases, and if ECS is lower, then the justification for the most aggressive net‑zero strategies becomes less clear. Moderate mitigation combined with adaptive resilience may be more effective and economically sustainable.
This is one of the central messages of the book, where I conclude that the overall body of empirical evidence suggests that implementing the aggressive SSP1 net‑zero mitigation policies may ultimately not be necessary to meet the Paris Agreement target of keeping global temperatures below 2 °C by 2100, since this same target could also be achieved under the more moderate and affordable SSP2 pathway, which emphasizes adaptation combined with moderate mitigation.
This is not a call for inaction. It is a call for evidence‑based realism.
7. Planetary harmonics: a possible origin of the observed climate cycles
A further theme explored in the final part of the book concerns the physical origin of the climatic harmonics observed in both modern and paleoclimate records. Over the years, I have shown that many of these oscillations — including the ~20‑year, ~60‑year, ~115‑year, and longer millennial and multimillennial cycles — closely match the harmonic structure produced by the gravitational and electromagnetic interactions among the planets, particularly Jupiter and Saturn.
This does not imply a simplistic deterministic mechanism. Rather, it suggests that the solar system behaves as a coupled dynamical system in which planetary motions can modulate solar activity and, through it, Earth’s climate. The coherence between planetary harmonics, solar variability, and climatic oscillations across the Holocene is striking, and it is difficult to interpret these correlations as mere coincidences.
In the book’s sixth and final section, I examine these models and mechanisms in detail, reviewing the astronomical foundations, the empirical evidence, and the potential physical pathways — from solar modulation to tidal forcing — that could link planetary dynamics to long‑term climate variability. While this line of research remains open and complex, it offers a promising framework for understanding the origin of the quasi‑periodic structures observed both in solar activity and climate change that current GCMs fail to reproduce.
8. What I hope this book contributes
My intention is not to close the debate, but to broaden it. Climate science is a dynamic field, and its strength lies in its capacity for self‑correction.
I hope the book encourages:
- a more pluralistic scientific dialogue,
- a deeper appreciation of natural variability,
- a renewed focus on empirical evidence,
- and a more cautious interpretation of model projections.
Above all, I hope it reminds readers that science advances not through consensus, but through continuous questioning.
9. Acknowledgments: the value of scientific dialogue
I am deeply grateful to the distinguished scholars who contributed the forewords to this book — Prof. M. Santosh, Prof. Alberto Prestininzi, and Prof. Judith Curry. Their perspectives reflect decades of experience across geology, geophysics, and climate science, and their willingness to engage with the themes of the book is both an honor and a testament to the importance of open scientific dialogue.
I also wish to thank the International Association for Gondwana Research (IAGR) and the Centro di Ricerca Previsione, Prevenzione e Controllo dei Rischi Geologici (CERI) at Sapienza University of Rome. Their support and scientific environments have played a meaningful role in fostering the interdisciplinary approach that underpins this work.
10. Closing thoughts
The climate system is complex, fascinating, and still not fully understood. My book is an attempt to explore this complexity with intellectual honesty and scientific curiosity. I look forward to the discussions it may inspire.
The book can be purchased at:
An excerpt of the book with the contents, forewords, and introduction can be downloaded from here:
Congratulations, Nicola!
Your new book is a welcome addition to the climate debate.
Merci pour vos informations !
Drum roll please. Cue in the ad homs from the usual suspects, devoid of any scientific value.
Thank you for the book. I look forward to reading it.
I was cleaning out my bookmarks the other day and noticed a compilation of hundreds of studies on solar from just one year. This wasn’t a list of nutjob authors. Regardless of the IPCC perspective, I think there is too much evidence to dismiss solar so blithely as the consensus seems to have done. To what an extent solar has some influence, who knows. That is for future generations to figure out.
Thanks again.
Setting aside the uncertainities for measurement errors/measure deficiencies, tsi has generally risen since the 1700’s which would indicate the sun is playing a larger factor than acknowledged by those fixated on GHG’s . Worth noting that other studies show a smaller increase in TSI over the same period.
https://www.researchgate.net/figure/Total-Solar-Irradiance-TSI-from-1610-to-2014_fig3_281267447
Thanks for the reference. The graph shows that except for the 11-year solar cycle, solar irradiance has been nearly constant since 1940. Too bad you are not able to see that.
Research indicates that solar output has changed over centuries, with periods of higher and lower activity. But by all means, near-term is all that’s relevant for many.
Are you suggesting the shift to a flat trend in solar activity has an immediate effect? Thus all anthropic warming since 1940? No delayed effect via the oceans storing the heat? Is the solar activity such that the increase in solar activity 1850 to 1940 brought the earths temp with immediate increases or is there a delayed effect that takes 40-70 years to fully emerge. Accepting the above would that not be an attempt to underweight the solar effect?
M Starkely,
If you are referring those questions to me; the only thing I’m ‘suggesting’ is what I wrote. But, I tend to agree with what you seem to be suggesting – we haven’t yet seen the full effects of increasing ocean heat content.
Kid, It is hard for non-scientists to figure out science. Probably good that you have given up on it.
https://scienceinsights.org/how-does-solar-activity-affect-climate-change/
ganon
Like I said, hundreds of studies on solar. Maybe they know more than you apparently think you know. Lack of self awareness seems to be one of your long suits.
That was funny!
Sure, Mr. Manager – I was referring to you. 100s of studies on solar – what was your understanding of what they said with respect to solar forcing change over the last hundred years?
Congratulations on your new book. I agree, harmonics play a central role. All four Jovian planets are involved as part of a resonant solar system.
I’ve known this for some time but have only recently been able to demonstrate a robust link to climate.
A 3560-Year Jovian Solar and Climate Cycle
https://doi.org/10.13140/RG.2.2.27244.01925
The core problem with ECS is water vapor feedback. WVF is clearly negative, not positive. And there are two major blunders (and many more..) why scientists get it wrong.
1. The regional and seasonal proxy hold a large positive lapse rate component. The lapse rate should be a negative feedback in the real world, but in these two proxies it is positive. That means first of all, these proxies do not work. But it also means, just assuming a negative lapse rate component, scientists confuse that as an indication of a strong water vapor feedback.
For instance, the observed slope might be 2W/m2/K, while the Planck Response is assumed to be 3.3W/m2/K, suggesting a negative Feedback of 3.3 – 2 = 1.3W/m2/K. This could be split up into 1.8W/m2/K of water vapor feedback and -0.5W/m2/K in lapse rate feedback, as 1.8 – 0.5 = 1.3. In fact that is the central estimate as with AR6.
With the large positive lapse rate component, say +1W/m2/K, in these proxies, the whole idea falls apart. You would end up with something like 0.3 + 1 = 1.3, that is a minimal water vapor component.
2. At least the interannual proxy might work, but there we have an even bigger problem. Scientists consistently use OLS regressions on this proxy (and the others). Given there are errors in the x-values (Ts), that is illicit and gives a far too low slope. Using a more reasonable regression, like TLS, the slope turns out consistently larger than the Planck Response, meaning a negative feedback.
https://greenhousedefect.com/the-holy-grail-of-ecs/regrettable-regressions-a-reanalysis
The natural WV negative feedback to SST change is 7% of the current total of 86.4W/m2 of latent heat loss by radiation to space per deg K. That is 6 W/m2 deg K. This also creates 7% more water vapour and 7% nore precipiatuin (The atmospheric water vapour of earth is turned over every 9 days, it doesn’t hang about, and all that latent heat is lost to space from the Tropopause on condensation by the 2nd law, constantly replaced by the EMR enrgy from the Sun. Maintaining the Earth’s enrgy balance a very dynamic balance on any serious planetary time scale , there is only 2 years of solar energy in the top 200m of the oceans, the static/ instantaneous/average energy balance system has a huge amount of energy constantly passing through its thin tropospheric skin. The majority of it returned to space by water vapour to the Tropopshre, where the latent heat relased as radiative loss to space through radiately transparent atmosphere upper Troposphere – all of it. It can’t go back anywhere. The models simply guess something else happens and WV only changes by 2-3% per degree, because their AGW isn’t enough to create 7% more WV without another natural energy input to change, even with Hansen’s dodgy GHE feedback from the extra WV.
Of course we KNOW natural change didn’t stop happening 2Ka BP in the natural record of proxy temps, archeology and history, and the rest of the energy over and above the IPCC’s 1.6W/m2 of AGW to release the 7% more energy in WV in response to the associated 1.5K change is from other natural causes, TBD but real. But muddlers can’t admit that, the no natural change condition is an IPCC grant funding tenet of the CO2 as dominat cause of change faith – so they invent a scientifically ridiculous “surface energy deficit”.
That says that oceans only release WV at 2-3% more per K in climate science, different from other science. That makes their models balance and makes the temperature sensitivity of their models to radaitive change look about 2.5 times greater as regards the WV feedback effect. “Surface energy deficit” is a sort of dark matter for astrophysicists or phlogiston for chemists. In effect, they add the postive feedback from GHE caused by additional water vapour, and claim the cooling effect of the same water vapour is insignificant.
So climate models are wortheless fairy tales because their major assumptions are wildly wrong, designed to support a narrative, not explain how the Earths strongly fed back energy balance works, using the data we have and can easily apply to determine the strong net negative feedbacks. As I have. It will be published together with a specific critique of the so obviously wrong GCMs, why their models are so bizarrely wrong and their predictions so far out in measured fact. We already have the data we need to quantify the natural negative feedback responses empirically. So we don’t need no models to know how Earth creates its own large stablislising feedbacks to any perturbation. More than able to stabilise the range of perturbations of up to 100W/m2 within a relatively limited range of GMST change (10-15K?) over the last 500Ma. 1.6W/m2 is really noise. Simple physics. The causes of natural change are harder, but their dynamic control a doddle to figure, if you stare at every aspect of it for 12 years until the pieces come together.
Catt, Brian, An Empirical Quantification of the Negative Feedbacks of Earth’s Energy Balance (2025) SSRN: http://dx.doi.org/10.2139/ssrn.5220078
Hi Brian (and E. Schaffer) –
“…we don’t need no models to know how Earth creates its own large stablislising feedbacks to any perturbation…”
In a famous paper published in 1967, Manabe and Wetherald calculated the effects of CO2 and water vapor on the Earth’s energy balance. Apparently their results differ from yours. Where do you suppose they went wrong?
(The 1967 paper has been cited about 2,500 times in subsequent research, and as you probably know, Manabe was recently awarded a prestigious prize for his work on climate modeling.)
And yet current versions of Manabe’s model show the greatest deviations from observations:
https://rclutz.com/wp-content/uploads/2024/04/cmip5-models-and-tropo-temps-observed.png
I would rather ask where I suppose they were right..?
As with their work, and many others, notably Ramathan, they all got lapse rate feedback wrong.
Climate and Weather are interchangeably linked. Weather changes can be measured in the length of a human life span. Climate change is modeled, and the ability to confirm these models are well outside the lifespan of anyone reading this. The majority of co2 in our atmosphere is coming from human induced land degradation, not petroleum. There are numerous measurable projects around the globe, that show when the carbon content of soils and biomes increase, weather patterns stabilize.
Excellent attempt to bring about reasoned thinking (e.g., an acknowledgment of ‘the pause’). It’s never possible to just get along with those who are fundamentally certain the way the rest of us must think and act is “settled truth.”
Congratulations, Nicola! I look forward to a good read.
A welcome change here (and necessary)
A couple of comments on the above if I may:
a) At point 2. ‘millennial‑scale cycles such as the Eddy cycle’. This is very important. I refer back to Javier’s https://judithcurry.com/2018/06/28/nature-unbound-ix-21st-century-climate-change/
specifically fig 122. Since then it became definite that the inflection points of this cycle are times of change. Whether the change is mild or drastic remains to be seen for the future. Evidence shows that for RWP at 173CE – a cycle peak – it was quite mild (except for the earthquakes and tsunamis, but unknown for weather). But for 2346bce, a cycle root, it was cataclysmic.
Why bother? : because the next peak is not far away
b) re point 7. What is definitely known (at my end) is that the driver is planetary. And that gravity it at the root of the matter. The 2346bce event is now known in detail.
Pingback: Solar Cycles and Natural Rhythms: A New Lens on Climate Dynamics - Climate Cosmos
“The prevailing attribution framework is the one currently advocated by the Intergovernmental Panel on Climate Change (IPCC). It assigns nearly all post‑1850 warming to anthropogenic forcings.”
If the IPCC is correct, then the story of the century has been hiding in plain sight: The former natural variability of climate has been replaced by anthropogenic forcing and nobody is questioning why it has happened or exactly how natural variability can be stopped.
clyde’s comment “….or exactly how natural variability can be stopped.”
fwiw – The assertion that natural variability became static has never been credible.
Quantitation is important. Don’t need to question why the ‘former’ natural variability has been replaced by anthropogenic forcing, because it hasn’t – it is still there, it is just that anthropogenic forcings are currently about an order of magnitude larger than stochastic ‘natural’ variability.
https://fiveable.me/introduction-climate-science/unit-7/natural-anthropogenic-climate-forcings/study-guide/30lCbxGLxnnAt2mZ
And yet, despite time acting like a low-pass filter, reducing the amplitude and slope of historical peaks, what is happening today does not appear unprecedented. What is happening currently is exactly what one would expect based on the behavior of past interglacials.
The evidence for high correlation between CO2 and global average temperature appears to be spurious. During the COVID shutdowns, there is weak support for the claim that CO2 has much impact on temperatures. See the graphs here:
https://wattsupwiththat.com/2022/03/22/anthropogenic-co2-and-the-expected-results-from-eliminating-it/
Clyde said, “What is happening currently is exactly what one would expect based on the behavior of past interglacials.”
Nope, past interglacials never exceeded 300 ppm CO2. That is what I would expect based on past interglacials.
Clyde,
You link to a four-year-old discussion about the source of the atmospheric carbon rise. Have you not yet understood that the undisputed empirical fact that the rate of carbon accumulation in the atmosphere is a bit less than half the rate of anthropogenic carbon emissions means that natural processes for the last century have been removing more carbon from the atmosphere than they have added? Natural reservoirs cannot be net sources when they have been measured to be net sinks.
Here is another way to understand it: There is general agreement that the planet has been “greening”, i.e., there is more carbon in the biosphere than there was a century ago. There is general agreement that the oceans are becoming less basic (“acidifying”) which is another way of saying there is more carbon in the oceans than there was a century ago. Of course there is more carbon in the atmosphere than there was a century ago. Ask yourself where is there LESS carbon now than a century ago. I think you will realize the only place where there is less carbon is in the fossil fuel reserves. Does that tell you anything?
Bushaw: When I suggested an increase during an interglacial, I was referring to temperature. After all, the definition of an interglacial is based on temperature and its effect on continental ice sheets and sea level. The glacial/interglacial stages were identified and named long before agency was assigned to CO2. An open mind would immediately be suspicious of a supposed driver having a higher concentration today than it what it was during the Eemian, when all but Alpine glaciers were gone from Greenland, while the Greenland Ice Sheet is still present today. That is what I was inferring with my suggestion that the apparent correlation between CO2 and temperature is spurious. While both variables are increasing, suggesting correlation, there is a problem with the “quantitation.” Earth should be much warmer and there should be much less ice if the temperature was being driven by CO2.
Andrews: You apparently didn’t notice that I am the author of the 4-year-old article. The age of the article is not germane. Why should I change my opinion when the data haven’t changed? An assumption that I made, and I apologize for not making the assumption explicit, is that IF CO2 is driving the temperature increase, a decrease in the anthro’ flux rate should be manifested in a decrease in the temperature increase rate. Instead, the temperature increased as though CO2 had no effect at all, as demonstrated by the small r-squared values.
You should be concerned about rates, not the integrated sums of a complex dynamic system. That is, under your assumptions, if CO2 is the main driver of temperature, an increase in anthro’ emission rates should result in warming, but a decrease in anthro’ emission rates should result in a decrease in the warming rate, even if the total atmospheric concentration increases.
Spencer, I already answered you.
B A Bushaw | March 11, 2026 at 10:52 am |
I am “one”, and you can’t tell me what I should “exactly expect”. I already told you what I expect, and your suddenly restricting it to temperature only, after the fact, is a apparent CYA attempt. Thanks anyway.
Clyde,
Your deductions from the 2020 Covid drop in human emissions are nonsense. In that year emissions dropped 6% compared to the previous year but recovered in 2021. That means one should expect the RATE Of INCREASE in carbon levels, not the levels themselves, to have temporarily, for one year, dipped 6%. With the seasonal variations, etc, the data is far too noisy to see that. The levels themselves, of course, continued to increase. You are dreaming if you expect to be able to see a change in the rate of temperature increase from this tiny perturbation.
You continue to show that you do not understand the carbon conservation argument. Perhaps you should discuss it with Dr. Curry. Following is an excerpt from the 2025 DOE Climate Assessment Report that she, Koonin, and the others signed off on:
“The annual increase in concentration is only about half of the CO2 emitted because land and ocean processes currently absorb “excess” CO2 at a rate approximately 50 percent of the human emissions. Future concentrations, and hence future human influences on the climate, therefore depend upon two components: (1) future rates of global human CO2 emissions, and (2) how fast the land and ocean remove extra CO2 from the atmosphere. We discuss each of these in turn. ”
I suspect they went to the trouble of making this explicit because they were embarrassed that some (you, Ron Clutz, Geoff Sherrington, Ed Berry…) continue to dispute the anthropogenic source of the atmospheric carbon increase, and that discredits other critiques of textbook climate science, and skepticism in general.
Why do we continue to have this “anthropogenic” theme as a cause or even THE cause of global warming?
Here is what happened, reported in 2012 on WUWT. Start quote –
“The scientists’ final draft of the 1995 (IPCC) Report said plainly, on five separate occasions, that no evidence of an anthropogenic influence on global climate was detectable, and that it was not known when such an influence would become evident.
“However, a single scientist, Dr. Ben Santer of Lawrence Livermore National Laboratory, rewrote the draft at the IPCC’s request, deleting all five statements, replacing them with a single statement to the effect that a human influence on global climate was now discernible, and making some 200 consequential amendments.
“These changes were considered by a political contact group, but they were not referred back to the vast majority of the authors whose texts Dr. Santer had tampered with, and whose five-times-stated principal conclusion he had single-handedly and unjustifiably negated.
“We now have the evidence of Prof. “Phil” Jones of the University of East Anglia, in one of the recently-released Climategate emails, that the warming of the past century falls well within the natural variability of the climate – consistent with the conclusion that Dr. Santer had negated.”
It is past time to decide if we want hard science or politicized story-telling to dominate our lives on climate change.
Geoff S
Good thing Santer corrected outdated information, anthropogenic effects were clearly observed by 1995. Callendar made first observations in the late 1930’s.
https://protonsforbreakfast.wordpress.com/2021/02/21/guy-callendar-precis-of-his-foundational-paper-on-global-warming/
Whether Santer was correct or not, or even whether he found a mouse on his doorstep–whether he threatened to beat Pat Michaels or not–making those changes to the report without notification was wrong, sleazy and puts the rest of his work under suspicion. It was something a Trumpian might do.
Thomas, You seem to have missed the point – IPCC asked Santer for the review.
Geoff, “Here is what happened, reported in 2012 on WUWT”. No, that may be what was reported on WUWT (such a reliable source-lol) but you have no idea of what actually happened.
We have this “anthropogenic theme” because it is responsible for roughly 90% (or more) of current climate change.
Also, judging by your post, looks like you went with politicized story-telling over hard science. No surprize there.
Santer claimed proof of human cause of global warming in his paper Nature July 1996 entitled: A search for human influences on the thermal structure of the atmosphere From the abstract:
“The observed spatial patterns of temperature change in the free atmosphere from 1963 to 1987 are similar to those predicted by state-of-the-art climate models incorporating various combinations of changes in carbon dioxide, anthropogenic sulphate aerosol and stratospheric ozone concentrations. The degree of pattern similarity between models and observations increases through this period. It is likely that this trend is partially due to human activities, although many uncertainties remain, particularly relating to estimates of natural variability.”
An article published the same month in World Climate Report was entitled:“Clearest Evidence” For Human “Fingerprint?” Results clouded if more complete data used The WCR essay concluded:
“We are frankly rather amazed that this paper could have emerged into the refereed literature in its present state; that is not to say that the work is bad, but that there are serious questions—similar to ours—that the reviewers should have asked.
The inescapable conclusions:
1. The vast majority of the “fingerprints” of the greenhouse effect are found way up in the atmosphere, especially in the stratosphere.
2. The “detection” models that were used either don’t predict very much future warming or were run with the wrong greenhouse effect and produce absurd results when the right numbers are put in.
3.And finally, down here in the lower atmosphere, the evidence is much more smudged and is based upon a highly selected set of data that, when viewed in toto, shows something dramatically different than what the paper purports.
The period that Santer et al. studied corresponds precisely with a profound warming trend in this region. But when all of the data (1957 to 1995) are included, there’s no trend whatsoever! We don’t know what to call this, but we believe that at least one of the 13 prestigious authors on this paper must have known this to be the case.
https://res.cloudinary.com/dhla0ygix/image/upload/v1562251342/Revised-figure-14_i69o3s.png
Ron, you might want to investigate the difference between “proof” and “evidence”.
I also had trouble finding the “World Climate Report” that you quote. Well, AI (ChatGPT) didn’t:
“The group you’re looking for is World Climate Report (WCR) — a now‑defunct, industry‑funded blog and newsletter run by Patrick Michaels and colleagues at the Greening Earth Society (GES) and Western Fuels Association. It was one of the earliest organized efforts to attack Ben Santer’s 1996 IPCC detection‑and‑attribution work.
The key point: World Climate Report absolutely did try to refute Santer’s 1996 IPCC Chapter 8 findings, and it did so as part of a coordinated campaign with other fossil‑fuel–aligned groups.
🧭 What “World Climate Report” actually was
– A contrarian climate newsletter/blog active from the mid‑1990s through the 2000s.
– Run by Patrick J. Michaels, Chip Knappenberger, and others associated with the Greening Earth Society (GES) — a front group created by the Western Fuels Association, a coal cooperative.
– Its mission was to undermine mainstream climate science, especially attribution findings.
A 1996 issue of World Climate Report is archived online, confirming the entity’s existence and its role as a GES publication.
🎯 How WCR targeted Santer’s 1996 IPCC work
WCR was part of a broader, coordinated attack on Santer following the 1995–1996 IPCC Second Assessment Report (SAR). The most aggressive component came from the Global Climate Coalition (GCC), but WCR amplified the same claims.
Key elements of the campaign:
– Accusations of “scientific cleansing” — alleging Santer improperly edited Chapter 8 of the IPCC report after review.
This originated in a GCC memo but was echoed by aligned groups, including WCR.
– Claims that Santer manipulated text to exaggerate human influence.
– Media amplification through outlets like The Wall Street Journal, Washington Times, and industry‑funded newsletters such as World Climate Report.
– Direct letters and pressure on the IPCC demanding retraction or republication of Chapter 8.
The scientific community — AMS, IPCC leadership, and many researchers — publicly defended Santer and rejected the allegations as unfounded and politically motivated.
🧩 Why WCR went after Santer
Santer’s 1996 detection‑and‑attribution chapter was the first time the IPCC concluded that:
“The balance of evidence suggests a discernible human influence on global climate.”
This was a watershed moment. Groups like WCR, GCC, and Western Fuels saw it as a direct threat to fossil‑fuel interests and launched a coordinated campaign to discredit both the science and the scientist.
WCR’s role was to provide a pseudo‑scientific veneer for these attacks — publishing articles, newsletters, and op‑eds claiming the IPCC process was corrupt and that Santer’s conclusions were invalid.
🧠 Why this matters historically
The WCR/GCC attacks on Santer are now widely recognized as one of the earliest large‑scale, coordinated disinformation campaigns targeting climate attribution science. They set the template for later efforts to undermine consensus findings.”
Ron,
We could debate all day whether the anthropogenic climate change “fingerprint” in 1996 was convincing or not. Are you arguing that it is still not convincing in 2026? And do you still argue that human emissions are not responsible for the rise in atmospheric carbon? I have not been on your site since you blocked my posts on that topic.
Nicola –
Over the years, I have become increasingly convinced that the climate system cannot be fully understood through a single explanatory lens.
It’s a really bad sign when you frontload your piece with a strawman of that magnitude.
It’s a really good sign that it provokes a Joshua.
Every other warm AMO phase is during each centennial solar minimum, this predicts a long term average AMO cycle frequency of 55 years, which is exactly what millennial scale AMO proxies show. The most recent 60 year and then 70 year long AMO cycles are because the Gleissberg solar minimum began 130 years before the current centennial minimum. While the Dalton minimum began only 80 years before the Gleissberg minimum, so the 1800’s had much shorter AMO cycles averaging around 40 years long.
Correlations of global sea surface temperatures with the solar wind speed:
Conclusions
Responses of sea-surface temperature to solar wind speed on the seasonal timescale have been found, and in the North Atlantic region in winter they resemble the North Atlantic Oscillation. At the locations of the peak (negative) response in the North Atlantic the SST decreases by approximately 1 °C for 100 km s−1 increase in solar wind speed.
https://www.sciencedirect.com/science/article/pii/S1364682616300360
AMO anomalies are coldest around sunspot cycle minimum during cold AMO phases, and never the coldest around sunspot cycle minimum during warm AMO phases. Because the major lows and highs in the solar wind shift relative to sunspot cycles, with major lows in 1969 and 1979-80 at sunspot cycle maximums, from the 1990’s the major lows are just after sunspot cycle minimum.
http://www.woodfortrees.org/graph/esrl-amo/from:1880/mean:13/plot/sidc-ssn/from:1880/normalise
The centennial minimum cycle is a product of the synodic cycles of Venus, Earth, Jupiter, and Uranus, Saturn is not involved. This cycle varies over a longer 863 year cycle, producing a series of longer (grand) centennial solar minima every 863 years (+/- 20yrs). The Eddy cycle is too long, the proposed Bray cycle does not exist in planetary cycles.
https://docs.google.com/document/d/1YOu7hHVEuaWWLuztj6ThEsJd7Z-765Uz-L68lQbRdbQ/edit?tab=t.0
Part quote “– is a product of the synodic cycles of Venus, Earth, Jupiter, and Uranus, Saturn is not involved”. You got that right. To be precise though it is ‘Uranus and Saturn are not involved’. From the Earth’s point of view it is the Gravity/distance factor that matters; at inferior conjunctions.
However the cycle -or compound cycle – is more variable, and on average it is the Eddy at about 980yrs. The effect of millennial change on humanity is a very good indicator. There are 8 cycles between the 8k2 event (~6150bce) and LIA at 1680CE, giving an average of 978yrs.
However both cycle inflection points are times of change. The missing factor is the moon, whose effect on earth in conjunction with the other two ‘trouble-makers’ is much greater than the rest.
Two Eddy inflection points are well known. The 173CE well recorded in Chinese annals; and the 2346bce that is everywhere in ancient history, and both confirmed in the very recent sediment studies.
Venus-Earth-Jupiter syzygies loosely follow sunspot cycle maximums, but cannot account for the changes in sunspot cycle lengths, or the occurrence of centennial minima and the cycle of variation in their lengths. The addition of Uranus accounts for all of it, purely by angular relationships and their collective synodic periods, without any need for hypothetical beat periods. My approach is to observe long enough until you can see how something functions, and then try to gather what the mechanisms may be, rather than first deciding what the mechanism is.
I arrived at this matter from another end. The periodic effect on humanity via astronomical and geological events. It is/was the mechanism that could not be determined with some certainty. Its effect is described everywhere in ancient texts. It is the gravitational effect of the planets (also clearly indicated in ancient texts), and in there distance matters. Uranus is too far away.
Nicola Scafetta has a paper on planet orbit relationships (the music of the spheres) and may partly explain why Uranus orbit may show up as mathematically linked, but not as a gravity effect on earth.
Having read more of the literature in question than any sentient creature, Grok has a differently opinion of Nicolas endorsers: M. Santosh and Prof. Alberto Prestininzi
China University of Geosciences Professor M. Santosh is a highly prolific and significant contributor to published Earth and environmental sciences with expertise in geochemistry, petrology, tectonics,& metallogeny. His work includes numerous highly cited papers on groundwater contamination (e.g., arsenic and fluoride), microplastics, phosphogypsum impacts, and some intersections with climate-related environmental health (e.g., a 2025 review on climate change, COVID-19, and emerging threats to environmental health).
Metrics indicate he has a strong academic impact in Earth sciences, with over 1,300 publications reported in some profiles and high citation counts in fields like geoscience. However, his primary focus is not core climate science (e.g., atmospheric physics, climate modeling, or IPCC-style attribution studies) but broader geological and environmental geoscience, with occasional extensions to climate-influenced topics like pollution or health risks.
Prof. Alberto Prestininzi (often spelled Prestininzi) is Emeritus Professor of Applied Geology at Sapienza University of Rome, where he headed a research center on geological risk prediction and control (CERI).
His publications appear more limited in mainstream climate literature, focusing instead on geology, engineering geology, landslides, natural risks, and hydrogeological issues. He has contributed pieces questioning anthropogenic climate change emphasis (e.g., a 2011 paper titled “The illusion of climate change and the responsibilities towards new generations for failure to prevent natural risks”) and has been involved in skeptic-oriented declarations (e.g., associated with Clintel/World Climate Declaration signatories).
His work touches on climate in the context of risk prevention but does not indicate a substantial body of peer-reviewed contributions in core climate science fields like atmospheric dynamics, radiative forcing, or global modeling.
Both contributed forewords or endorsements to Nicolas Scafetta’s recent book The Frontier of Climate Science: Solar Variability, Natural Cycles and Model Uncertainty.
Their involvement with Scafetta’s work aligns with perspectives skeptical of dominant IPCC narratives, but this does not equate to broad, central roles in the field’s primary literature on anthropogenic climate change attribution, projections, or impacts.
I am disappointed that Dr. Scafetta has apparently chosen not to respond to comments here, but perhaps he will eventually. I would like to ask him about his 2011 paper “Climate Change Attribution Using Empirical Decomposition of Climatic Data”.
https://web.archive.org/web/20210607052742/https://wattsupwiththat.files.wordpress.com/2011/07/loehlescafetta.pdf
The abstract includes the following:
“A 21st Century forecast suggests that climate may remain approximately steady until 2030-2040, and may at most warm 0.5-1.0°C by 2100 at the estimated 0.66°C/century anthropogenic warming rate, which is about 3.5 times smaller than the average 2.3°C/century anthropogenic warming rate projected by the IPCC up to the first decades of the 21st century. However, additional multisecular natural cycles may cool the climate further.”
As Dr. Scafetta is “Rethinking Climate Change”, perhaps he has revisited the analysis that led to this wrong prediction. Do I have to buy the book to find out?
Pax Christi. Thanks.
A general question: what kind of “science” is so called “climate science” if its model(s) are based on the assumption that the main cause (factor) of so called “global temperature” is the function of ONLY “human-made” (or fossils) that accounts of about 0.000 4% of Earth’s atmosphere (or 0.00004 of the volume of atmosphere or 35 ppm while natural co2 counts 380 ppm(data from David Dilley, 2018, Tom Nelson podcast#216; a similar estimation from other literature, F.Vahrenholt, S.Luning,Die Kalte Sonne.AD 2012 or Neglected Sun,ch.2,p.17(Polish Edition)?
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