Dr. Nicola Scafetta summarizes "why the anthropogenic theory proposed by the IPCC should be questioned"

Dr. Nicola Scafetta has written an extensive summary of the state of climate science today. He’s done some very extensive analysis of the solar contribution that bears examination. Pay particular attention to this graph from page 49:

Top: The figure shows the global surface temperature (black) detrended of its quadratic fit function as done in Figure 1. The data are plotted against the 60 year modulation of the speed of the sun relative to the center of mass of the solar system (red) shown in Appendix T. The 60 year modulation of SCMSS has been time-shifted by +5 years. Bottom: The figure shows the global surface temperature (black) filtered within its two decadal oscillation. The temperature modulation is plotted against the SCMSS (red) shown in Appendix T. No time-shift has been applied. The figures suggest that the 60 and 20 year modulation of the SCMSS can be used for forecasting these global surface temperature oscillations and has been used to reproduce the forecast modulation curves in Figure 13.

WUWT readers may remember him from some previous papers and comments he’s written that have been covered here:

Scafetta: New paper on TSI, surface temperature, and modeling

Scafetta: Benestad and Schmidt’s calculations are “robustly” flawed.

Scafetta-Wilson Paper: Increasing TSI between 1980 and 2000 could have contributed significantly to global warming during the last three decades

He writes to me with this introduction:

On February 26, 2009 I was invited by the Environmental Protection Agency Office of the Science Advisor (OSA) and National Center for Environmental Economics (NCEE) to present a talk about my research on climate change. I thought that the best way to address this issue was to present an overview of all topics involved about the issue and their interconnections.

So, I prepared a kind of holistic presentation with the title  “Climate Change and Its Causes, A Discussion about Some Key Issues”. Then, a colleague from Italy who watched my EPA presentation suggested me to write a paper in Italian and submit it to an Italian science journal which was recently published.

I realized that it could be done more, so I thought that actually writing a short booklet summarizing all major topics and possible future perspectives could be useful for the general public. So, this work I am presenting here and which is supposed to be read by the large interested public came out. It contains a translation into English of my Italian paper plus numerous notes and appendixes covering also the most recent results that have transformed the original paper in a comprehensive booklet.

This booklet covers more or less all topics I believe to be important for understanding the debate on climate change. Herein, I argue why the anthropogenic theory proposed by the IPCC should be questioned.

Finally, a suggestion for those who would like to print it, the best way is to use the “booklet option” of the printers and staple it in the middle.


Download the report here (PDF -warning over 10 MB – long download time on slow connections)

This work covers most topics presented by Scafetta at a seminar at the U.S. Environmental Protection Agency, DC USA, February 26, 2009. A video of the seminar is here:

The Italian version of the original paper can be downloaded (with possible journal restrictions) from here


Here is the table of contents, there’s something in this report for everyone:

Climate Change and Its Causes: A Discussion About Some Key Issues

Introduction … 4

The IPCC’s pro-anthropogenic warming bias … 6

The climate sensitivity uncertainty to CO2 increase … 8

The climatic meaning of Mann’s Hockey Stick temperature graph … 10

The climatic meaning of recent paleoclimatic temperature reconstructions … 12

The phenomenological solar signature since 1600 … 14

The ACRIM vs. PMOD satellite total solar irradiance controversy … 16

Problems with the global surface temperature record … 18

A large 60 year cycle in the temperature record … 19

Astronomical origin of the climate oscillations … 22

Conclusion … 26

Bibliography … 27


A: The IPCC’s anthropogenic global warming theory … 29

B: Chemical vs. Ice-Core CO2 atmospheric concentration estimates … 30

C: Milky Way’s spiral arms, Cosmic Rays and the Phanerozoic temperature cycles … 31

D: The Holocene cooling trend and the millennial-scale temperature cycles … 32

E: The last 1000 years of global temperature, solar and ice cover data … 33

F: The solar dynamics fits 5000 years of human history … 34

G: The Medieval Warm Period and the Little Ice Age – A global phenomenon … 35

H: Compatibility between the AGWT climate models and the Hockey Stick … 36

I: The 11-year solar cycle in the global surface temperature record … 37

J: The climate models underestimate the 11-year solar cycle signature … 38

K: The ACRIM-PMOD total solar irradiance satellite composite controversy … 39

L: Willson and Hoyt’s statements about the ACRIM and Nimbus7 TSI published data .. 40

M: Cosmic ray flux, solar activity and low cloud cover positive feedback … 41

N: Possible mechanisms linking cosmic ray flux and cloud cover formation … 42

O: A warming bias in the surface temperature records? … 43

P: A underestimated Urban Heat Island effect? … 44

Q: A 60 year cycle in multisecular climate records … 45

R: A 60 year cycle in solar, geological, climate and fishery records … 46

S: The 11-year solar cycle and the V-E-J planet alignment … 47

T: The 60 and 20 year cycles in the wobbling of the Sun around the CMSS … 48

U: The 60 and 20 year cycles in global surface temperature and in the CMSS … 49

V: A 60 year cycle in multisecular solar records … 50

W: The bi-secular solar cycle: Is a 2010-2050 little ice age imminent? … 51

X: Temperature records do not correlate to CO2 records … 52

Y: The CO2 fingerprint: Climate model predictions and observations disagree … 53

Z: The 2007 IPCC climate model projections. Can we trust them? … 54


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Mia Nony

First, they called it “global warming”. Then they noticed there had been no warming for 15 years, and cooling for 9, so they hastily renamed it “climate change”. Then they noticed the climate was changing no more than it ever had, so they tried “energy security”, and even named a Congressional Bill after it. Then they noticed that most Western nations already had bountiful energy security, in the form of vast, untapped domestic supplies of oil, gas, coal, or all three, so they switched to “ocean acidification”.”


((This work covers most topics presented by Scafetta at a seminar at the U.S. Environmental Protection Agency, DC USA, February 26, 2009….))
..And yet our government is bent on listening to no such thing. Immediately after, the EPA listed Carbon Dioxide as a “harmful gas.”

Steve in SC

Very interesting. Downloaded at once.

R Shearer

Wait a minute, how could we possibly influence the center of mass of the solar system?


Blimey – best get my reading specs on!

stan stendera

This post is why WUWT is the cutting edge of truth.

Robert of Ottawa

What is meant by “de-trended”?

Robert of Ottawa

OK the first page of the booklet makes clear the answer to my question :^)

Philip Richens

This is a wonderfully clear and impressive presentation. Very welcome, very recommended. Thank you.


Wait, do I smell a barycentre?
Note the cycle of the PDO is about the same as that 60 year cycle.
Ooops, Leif incoming.


Well now. Maybe the Sun and the Oceans really do have something major to say? Whodathunkit?


Thank you Dr. Scaffeta for putting this work together. I’ve just downloaded it and look forward to a little light reading before bed.

Prof. Horst Malberg , retired director of Berlin Free University’s Institute of Meteorology has just published “La Niña – El Niño and Solar Influence: Climatic Trends 1950 – 2008” and “Solar influence on long-term climate change, globally since 1860, in Central Europe since 1672” — a pair of real game-changers for the climate debate that demolishes AGW and, IMHO, deserve widest-possible dissemination. Can’t fit them in here, so please e-mail me an address.


Interesting. I do not think that anyone has an argument against the TSI effecting things to some extent. But it appears that the effect is rather small and somewhat secondary. D’Aleo found that adding it to his model along with the PDO and AMO did not add much.

R. Gates

Thanks for bringing this to my attention. I actually hadn’t heard of this work before. I shall download and read Dr. Scaffeta’s entire report “Climate Change and Its Causes” with much interest.
From a quick preview, it appears that he believes that we are in for a period of global cooling, bottoming out in 2030 or so, and it’s got nothing to do with GH gases, but is related to solar and astronomical cycles. Is this correct? And if this is what he predicts, then his hypothesis can be put directly up against the AGW hypothesis, which would state that we should see many new record global high temps between now and 2030, along with the disappearance of summer arctic sea ice, etc.
Both theories can’t be correct, and it even looks as though, according to Dr. Scaffeta’s own graphs, that we should already be seeing a downward plunge in temperatures heading to that 2030 low. If we see a new global record warm year in 2010, as the Met Office (and I believe) will likely happen, what problems would that represent for Dr. Scaffeta’s hypothesis?

Long period Lunar declinational influences on the global circulation that may not be much different from the above in essence, although not as well researched yet.
Downloading the PDF file now thanks for the input.

Sara Chan

The author’s first name is Nicola, not Nicolas. Yes, he is a man; see
Reply: Fixed ~ ctm


Very interesting. Thanks for the download information.
The Figure 13 chart is quite telling.

Dr. Scafetta has recently honoured us participating in a meeting held in Italy on february 27th. In that meeting I asked him the permission to make an on line interview with questions directly from the readers. The discussion (in italian) is ongoing here http://www.climatemonitor.it/?p=8378.


I give up. What’s TSI?
[Total Solar Irradiance. ~dbs]


Found it, buried deep in his PDF. TSI = total solar irradiance.


I’ve read it. And this has been presented to the EPA?
I noticed that you didnt elaborate much on CRU station removal, and not much on GISS versus UHI opposite compensation. But, since you were to present it to the EPA, I can understand it.
A very interesting read. Maybe this can help in trying to turn the IPCC into another direction? Like, changing
The IPCC mission:
“The IPCC reviews and assesses the most recent scientific, technical and socioeconomic information produced worldwide relevant to the understanding of human induced climate change.”
For example;
“The IPCC reviews and assesses the most recent scientific information produced worldwide relevant to the understanding of human induced pollution.”


Is Scafetta going to let RealClimate have the code that he used for his paper?
Or is he going to use the same excuses that Michael Mann, Tamino, & Co have been using?


I have just downloaded it and haven’t yet had a chance to study it but it seems we have needed a compendium of research summaries and how they relate to the AGW debate. Perhaps this can serve that purpose.

Dr. Scaffeta welcome to the club of ‘pseudoscience’, why not peruse, by now now infamous, set graphs and equations which have earned me a rare distinction of a ‘cycloramic in extreme’.


well; that’s going to keep me quite for a while…

Peter Miller

This is all a bit too scientific and factual for our friends at Real Climate, Ed Miliband, Patchi, Jones, Mann et alia.
I expect the silence of their response will be deafening. Perhaps the argument they will use will be that any comments on climate by people with Italian sounding names are irrelevant – makes as much sense as most of their arguments.


For clarification, was Dr. Scafatta “invitation” to present to the EPA mean he was paid by the EPA to produce a research product, paid expenses to present independent research, or prepared this with no contractual relationship with the EPA. (I haven’t been able to complete a download yet, so I apologize if those details are included.)


At long last! An Overview! I can see where all my spare time will be going, for a while.
However I’ll bet a nickel that this only scratches the surface of the countless interactions which make up the entire “system.”
My question to anyone who steps out their door, looks up at the sky, and thinks they have the “system” all figured out is, “Are you sure you aren’t being just a little bit arrogant?”


I clicked Submit, before saying that I found the paper very, very interesting. Thank you very much for posting here on WUWT!
Regards, kwik.

john pattinson

?? The figure shows the global surface temperature (black) detrended of its quadratic fit function as done in Figure 1. ??
?? The 60 year modulation of SCMSS has been time-shifted by +5 years ??
So the detrended temperatures fit the variation in the sun if we shift it by 8% .
So what causes the trend? Now there must be a study there?

Dan (Norway)



Discover Magazine has a very interesting two part interview with Judy Curry and Michael ‘Piltdown’ Mann. Judy seems to have caught on to the importance of the oceanic oscillations to the cooling from the ’40s to the ’70s and the subsequent warming, whereas Mann seems to willfully disregard it. Found through tomnelson.blogspot.com

CRS, Dr.P.H.

Please don’t read any of this, because the science is already settled. I have spoken.
Signed, *Man Behind the Curtain*

John from CA

Thank You Dr. Scaffeta for presenting your work to the general public. I look forward to reading it in depth.
Best Regards,
John from California


R Shearer (11:13:40) :
“Wait a minute, how could we possibly influence the center of mass of the solar system?”
Because the masses (planets) are constantly changing positions and their orbits are slightly elliptical.

John from CA

For heavens sake, I download the pdf and the title page was the first surprise. Many apologies to Dr. Nicola Scafetta NOT “Scaffeta” as it appears in the headline of this article and my last comment.
[Fixed, thanks. ~dbs, mod.]


It has recently been proven that if a report or article has any errors at all, the entire content is rendered meaningless, or perhaps even a hoax.
What then, should we make of the erroneous spelling of Dr. Nicola Scafetta, above? Is this some attempt at covering up previous publications by Dr. Nicola Scafetta? Is there some recent reports of criminal activity circulating on the Internet that a misspelled name would fail to turn up? Has the editorial integrity of WUWT broken down, requiring a total redesign so that this never happens in the future?
The implications of this error are vast – I think we better clear this up before we talk about the contents of the article at all.


One of the major cycles in the Chinese astrological calendar, which was/is used a lot for determining ‘lucky’ days for planting etc., consists of 60 years. This is made up of the 12 animals, which change every year, and the 5 elements, which change every two years. Each animal/element therefore occurs every 60 years.
The point being that maybe the cycle observed by Dr. Nicola Scaffeta has been observed in the past over an extended period of time.

JP Miller

It’s interesting that one of Scafetta’s main arguments seems to be similar to, dare I say it, a “Landscheidt” approach to explaining climate cycles. If this is right, it would be ironic that the one “scientific” topic banned on this skeptic’s site, which has done so much to challenge AGW, is a discussion of exactly that climate mechanism. Or, am I off base here?
REPLY: Yes I noted that, but I decided that the best approach is to face it head on, if it is junk, it will shake out. – Anthony


Ron (13:19:58) :
R Shearer (11:13:40) :
“Wait a minute, how could we possibly influence the center of mass of the solar system?”
Ron, Shearer was being sarcastic. If we are going to force these uncanny natural cycles to match the IPPC models, how much world-wide taxation would we need?


Landscheidt had talked about this for many years. (Why is it not ok to mention his name on this forum??)
I even wrote a paper on the (slightly less than) twenty year pattern in Iowa tree ring data. I speculated that it was linked to the Saturn/Jupiter lap. It was published back in 1995, I think. We should be susceptible to drought in the midwestern US over the next few years from this cycle. I suspect the AGW alarmists will seize this, if indeed it does occur, as proof of continued global warming.

Here is my take on a natural climate cycle


How could we possibly influence the center of mass of the universe? Maybe jumping up and down all at once, everyone on earth? Hmmm, no, that won’t do it.
I got it! Everyone turn off your lights for an hour. Pick a day and just do it. Maybe sacrifice a few virgins, too.

Jeff B.

If Al Gore and his sycophant team of Hansen, Smith, Jones, Trenberth, et. al. were smart, they would go hide quietly now. Their game is over.

Richard Telford

Quite amazing. Scafetta manages to pack in almost every “sceptical” talking point, paying no attention to their credibility or consistency.
So we have doubts about the instrumental temperature record, but no doubts about Beck’s CO2 compilation despite the internal contraditions of the latter. Scafetta argues that the recent increase in atmospheric CO2 has a considerable natural component due to solar induced warming. Were that the case, it would suggest that feedbacks are huge. Fortunately, the most recent analysis, even covered on WUWT, would suggest otherwise. We even have the lie that Jones said their had been no warming since 1995 (rather than there being no statistically signigicant warming).
And then we have the baryocentric argument, though without naming it as such. As always, it is presented without any consideration of its physical plausibility. Tides on earth have a minor contribution to the climate system, increasing mixing in the ocean. The tides on the sun are going to be orders of magnitude smaller, and have a period orders of magnitude longer. It is difficult to concieve of them having an important effect.

Dr. Scafetta, thank you for your work and for publishing this for free. It is a fascinating article. I sent the link to numerous colleagues.
This will create conversation for many years, I am sure.
Roger E. Sowell, Esq.
Marina del Rey, California

Dr. Scafetta (and his co-authror West) were earlier contributors to the IPCC reports in the late 1990’s and early 2000’s. Remember these were the days before the hockey stick and the outrageous claims of impending doom. In the early to mid 2000’s Scafetta and West started to downgrade the impact of anthropogenic caused warming to around half their earlier estimates based on their more recent studies. This occurred at a time that Mann and the “Team” introduced the hockey stick and began pushing for a more exaggerated portrayal of anthropogenic induced doom. While Scafetta was still recognized as a leading contributor his later work just didn’t fit the narrative. So he was relegated to the “has beens” of climatology with little of his later work being considered for inclusion.
Finally, the political environment in climatology has changed enough so that sound views of rational scientists can once again be heard. Thank you Dr. Scafetta for staying true to your convictions and speaking only where the science compels you to speak.


Why is it that when I read the posts on this web site I get angry?
You may not agree, but I am a true skeptic.
What I keep seeing here is not skepticism but political machinations.
I do not see a desire to find the truth, and to thus come to a logical conclusion.
rather I see blind parroting of “slogans” and outright toadyism.
This is not science. It is anti-science.
sad just sad
The really sad part is 50 years from now, what will your children and grand childrens opinion be of you?


“Anu (13:28:07) :
It has recently been proven that …”
Lots of words for a really lame joke.