Scafetta prediction widget update

By Dr. Nicola Scafetta

It is time to update my widget comparing the global surface temperature, HadCRUT3 (red and blue), the IPC 2007 projection (green) and my empirical model (black thick curve and cyan area) based on a set of detected natural harmonics (period of approximately: 9.1, 10-11, 20 and 60 years) which are based on astronomical cycles, plus a corrected anthropogenic warming projection of about 0.9 oC/century. The yellow curve represents the harmonic model alone without the corrected anthropogenic warming projection and represents an average lower limit.

The proposed astronomically-based empirical model represents an alternative methodology to reconstruct and forecast climate changes (on a global scale, at the moment) which is alternative to the analytical methodology implemented in the IPCC general circulation models. All IPCC models are proven in my paper to fail to reconstruct all decadal and multidecadal cycles observed in the temperature since 1850. See details in my publications below.


As the figure shows, the temperature for Jan/2012 was 0.218 oC, which is a cooling respect to the Dec/2011 temperature, and which is about 0.5 oC below the average IPCC projection value (the central thin curve in the middle of the green area). Note that this is a very significant discrepancy between the data and the IPCC projection.

On the contrary, the data continue to be in reasonable agreement with my empirical model, which I remind, is constructed as a full forecast since Jan/2000.

In fact the amplitudes and the phases of the four cycles are essentially determined on the basis of the data from 1850 to 2000, and the phases are found to be in agreement with appropriate astronomical orbital dates and cycles, while the corrected anthropogenic warming projection is estimated by comparing the harmonic model, the temperature data and the IPCC models during the period 1970-2000. The latter finding implies that the IPCC general circulation models have overestimated the anthropogenic warming component by about 2.6 time on average, within a range between 2 to 4. See original papers and the dedicated blog article for details: see below.

The widget also attracted some criticisms from some readers of WUWT’s blog and from skepticalscience

Anthony asked me to respond to the criticism, and I am happy to do so. I will respond five points.

  1. Criticism from Leif Svalgaard.

As many readers of this blog have noted, Leif Svalgaard continuously criticizes my research and studies. In his opinion nothing that I do is right or worth of consideration.

About my widget, Leif claimed many times that the data already clearly contradict my model: see here 1, 2, 3, etc.

In any case, as I have already responded many times, Leif’s criticism appears to be based on his confusing the time scales and the multiple patterns that the data show. The data show a decadal harmonic trending plus faster fluctuations due to ElNino/LaNina oscillations that have a time scale of a few years. The ENSO induced oscillations are quite large and evident in the data with periods of strong warming followed by periods of strong cooling. For example, in the above widget figure the January/2012 temperature is out of my cyan area. This does not mean, as Leif misinterprets, that my model has failed. In fact, such pattern is just due to the present La Nina cooling event. In a few months the temperature will warm again as the El Nino warming phase returns.

My model is not supposed to reconstruct such fast ENSO induced oscillations, but only the smooth decadal component reconstructed by a 4-year moving average as shown in my original paper figure: see here for the full reconstruction since 1850 where my models (blue and black lines) well reconstruct the 4-year smooth (grey line); the figure also clearly highlights the fast and large ENSO temperature oscillations (red) that my model is not supposed to reconstruct.

As the widget shows, my model predicts for the imminent future a slight warming trending from 2011 to 2016. This modulation is due to the 9.1 year (lunar/solar) and the 10-11 year (solar/planetary) cycles that just entered in their warming phase. This decadal pattern should be distinguished from the fast ENSO oscillations that are expected to produce fast periods of warming and fast period of cooling during these five years as it happened from 2000 to 2012. Thus, the fact that during LaNina cooling phase, as right now, the temperature may actually be cooling, does not constitute a “proof” that my model is “wrong” as Leif claimed.

Of course, in addition to twist numerous facts, Leif has also never acknowledged in his comments the huge discrepancy between the data and the IPCC projection which is evident in the widget. In my published paper [1], I did report in figure 6 the appropriate statistical test comparing my model and the IPCC projection against the temperature. The figure 6 is reported below


The figure reports a kind of chi-squared statistical test between the models and the 4-year smooth temperature component, as time progress. Values close to zero indicate that the model agrees very well with the temperature trending within their error range area; values above 1 indicate a statistically significant divergence from the temperature trending. It is evident from the figure above that my model (blue curve) agrees very well with the temperature 4-year smooth component, while the IPCC projection is always worst, and statistically diverges from the temperature since 2006.

I do not expect that Leif changes his behavior against me and my research any time soon. I just would like to advise the readers of this blog, in particular those with modest scientific knowledge, to take his unfair and unprofessional comments with the proper skepticism.

  1. Criticism about the baseline alignment between the data and the IPCC average projection model.

A reader dana1981 claimed that “I believe Scafetta’s plot is additionally flawed by using the incorrect baseline for HadCRUT3. The IPCC data uses a baseline of 1980-1999, so should HadCRUT.”

This reader also referred to a figure from skepticalscience, shown below for convenience,


that shows a slight lower baseline for the IPCC model projection relative to the temperature record, which give an impression of a better agreement between the data and the IPCC model.

The base line position is irrelevant because the IPCC models have projected a steady warming at a rate of 2.3 oC/century from 2000 to 2020, see IPCC figure SPM.5. See here with my lines and comments added


On the contrary, the temperature trending since 2000 has been almost steady as the figure in the widget clearly shows. Evidently, the changing of the baseline does not change the slope of the decadal trending! So, moving down the baseline of the IPCC projection for giving the illusion of a better agreement with the data is just an illusion trick.

In any case, the baseline used in my widget is the correct one, while the baseline used in the figure on skepticalscience is wrong. In fact, the IPCC models have been carefully calibrated to reconstruct the trending of the temperature from 1900 to 2000. Thus, the correct baseline to be used is the 1900-2000 baseline, that is what I used.

To help the readers of this blog to check the case by themselves, I sent Anthony the original HadCRUT3 data and the IPCC cmip3 multimodel mean reconstruction record from here . They are in the two files below:



As everybody can calculate from the two data records that the 1900-2000 average of the temperature is -0.1402, while the 1900-2000 average of the IPCC model is -0.1341.

This means that to plot the two records on the common 1900-2000 baseline, there is the need to use the following command in gnuplot

plot “HadCRUT3-month-global.dat”, “itas_cmip3_ave_mean_sresa1b_0-360E_-90-90N_na.dat” using 1:($2 – 0.0061)

which in 1850-2040 produces the following graph


The period since 2000 is exactly what is depicted in my widget.

The figure above also highlights the strong divergences between the IPCC model and the temperature, which are explicitly studied in my papers proving that the IPCC model are not able to reconstruct any of the natural oscillations observed at multiple scales. For example, look at the 60-year cycle I extensively discuss in my papers: from 1910 to 1940 a strong warming trending is observed in the data, but the warming trending in the model is far lower; from 1940 to 1970 a cooling is observed in the data while the IPCC model still shows a warming; from 1970 to 2000, the two records present a similar trending (this period is the one originally used to calibrate the sensitivities of the models); the strong divergence observed in 1940-1970, repeats since 2000, with the IPCC model projecting a steady warming at 2.3 oC/century , while the temperature shows a steady harmonically modulated trending highlighted in my widget and reproduced in my model.

As explained in my paper the failure of the IPCC model to reconstruct the 60-year cycle has large consequences for properly interpreting the anthropogenic warming effect on climate. In fact, the IPCC models assume that the 1970-2000 warming is 100% produced by anthropogenic forcing (compare figures 9.5a and 9.5b in the IPCC report) while the 60-year natural cycle (plus the other cycles) contributed at least 2/3 of the 1970-2000 warming, as proven in my papers.

In conclusion, the baseline of my widget is the correct one (baseline 1900-2000). My critics at skepticalscience are simply trying to hide the failure of the IPCC models in reconstructing the 60-year temperature modulation by just plotting the IPCC average simulation just since 2000, and by lowering the baseline apparently to the period 1960-1990, which is not where it should be because the model is supposed to reconstruct the 1900-2000 period by assumption.

It is evident that by lowering the base line a larger divergence would be produced with the temperature data before 1960! So, skepticalscience employed a childish trick of pulling a too small coversheet from a too large bed. In any case, if we use the 1961-1990 baseline the original position of the IPCC model should be shifted down by 0.0282, which is just 0.0221 oC below the position depicted in the figure above, not a big deal.

In any case, the position of the baseline is not the point; the issue is the decadal trend. But my 1900-2000 baseline is in the optimal position.

  1. Criticism about the chosen low-high boundary levels of the IPCC average projection model (my width of the green area in the widget).

Another criticism, in particular by skepticalscience, regards the width of the boundary (green area in the widget) that I used, They have argued that

“Most readers would interpret the green area in Scafetta’s widget to be a region that the IPCC would confidently expect to contain observations, which isn’t really captured by a 1-sigma interval, which would only cover 68.2% of the data (assuming a Gaussian distribution). A 2-sigma envelope would cover about 95% of the observations, and if the observations lay outside that larger region it would be substantial cause for concern. Thus it would be a more appropriate choice for Scafetta’s green envelope.”

There are numerous problems with the above skepticalscience’s comment.

First, the width of my green area (which has a starting range of about +/- 0.1 oC in 2000) coincides exactly with what the IPCC has plotted in his figure figure SPM.5. Below I show a zoom of IPCC’s figure SPM.5


The two red lines added by me show the width at 2000 (black vertical line). The width between the two horizontal red lines in 2000 is about 0.2 oC as used in my green area plotted in the widget. The two other black lines enclosing the IPCC error area represent the green area enclosure reported in the widget. Thus, my green area accurately represents what the IPCC has depicted in its figure, as I explicitly state and show in my paper, by the way.

Second, skepticalscience claims that the correct comparison needed to use a 2-sigma envelope, and they added the following figure to support their case


The argument advanced by skepticalscience is that because the temperature data are within their 2-sigma IPCC model envelope, then the IPCC models are not disproved, as my widget would imply. Note that the green curve is not a faithful reconstruction of my model and it is too low: compare with my widget.

However, it is a trick to fool people with no statistical understanding to claim that by associating a huge error range to a model, the model is validated.

By the way, contrary to the claim of sckepticalscience, in statistics it is 1-sigma envelope width that is used; not 2-sigma or 3-sigma. Moreover, the good model is the one with the smallest error, not the one with the largest error.

In fact, as proven in my paper, my proposed harmonic model has a statistical accuracy of +/- 0.05 oC within which it well reconstructs the decadal and multidecadal modulation of the temperature: see here.

On the contrary, if we use the figure by skepticalscience depicted above we have in 2000 a 1-sigma error of +/- 0.15 oC and a 2-sigma error of +/- 0.30 oC. These robust and fat error envelope widths are between 3 and 6 times larger than what my harmonic model has. Thus, it is evident from the skepticalscience claims themselves that my model is far more accurate than what the IPCC models can guarantee.

Moreover, the claim of skepticalscience that we need to use a 2-sigma error envelope indirectly also proves that the IPCC models cannot be validated according the scientific method and, therefore, do not belong to the realm of science. In fact, to be validated a modeling strategy needs to guarantee a sufficient small error to be capable to test whether the model is able to identify and reconstruct the visible patterns in the data. These patterns are given by the detected decadal and multi-decadal cycles, which have amplitude below +/- 0.15 oC: see here. Thus, the amplitude of the detected cycles is well below the skepticalscience 2-sigma envelope amplitude of +/- 0.30 oC, (they would even be below the skepticalscience 1-sigma envelope amplitude of +/- 0.15 oC).

As I have also extensively proven in my paper, the envelope of the IPCC model is far larger than the amplitude of the temperature patterns that the models are supposed to reconstruct. Thus, those models cannot be properly validated and are useless for making any useful decadal and multidecadal forecast/projection for practical society purpose because their associated error is far too large by admission of skepticalscience itself.

Unless the IPCC models can guarantee a precision of at least +/- 0.05 oC and reconstruct the decadal patterns, as my model does, they cannot compete with it and are useless, all of them.

  1. Criticism about the upcoming HadCRUT4 record.

Skepticalscience has also claimed that

“Third, Scafetta has used HadCRUT3 data, which has a known cool bias and which will shortly be replaced by HadCRUT4.”

HadCRUT4 record is not available yet. We will see what happens when it will be available. From the figures reported here it does not appear that it will change drastically the issue: the difference with HadCRUT3 since 2000 appears to be just 0.02 oC.

In any case for an optimal matching the amplitudes of the harmonics of my model may need to be slightly recalibrated, but HadCRUT4 already shows a clearer cooling from 1940 to 1970 that further supports the 60-year natural cycle of my model and further contradicts the IPCC models. See also my paper with Mazzarella where the HadSST3 record is already studied.

  1. Criticism about the secular trending.

It has been argued that the important issue is the upward trending that would confirm the IPCC models and their anthropogenic warming theory.

However, as explained in my paper, once that 2/3 of the warming between 1970 and 2000 is associated to a natural cycle with solar/astronomical origin (or even to an internal ocean cycle alone) the anthropogenic warming trending reproduced by the models is found to be spurious and strongly overestimated. This leaves most of the secular warming tending from 1850 to 2012 as due to secular and millennial natural cycles, which are also well known in the literature.

In my published papers, as clearly stated there, the secular and millennial cycles are not formally included in the harmonic model for the simple reason that they need to be accurately identified: they cannot be put everywhere and the global surface temperature is available only since 1850, which is a too short period for accurately locate and identify these longer cycles.

In particular, skepticalscience has argued that the proposed model (by Loehle and Scafetta) based only on the 60-year and 20-year cycles plus a linear trending from 1850 to 1950 and extrapolated up to 2100 at most, must be wrong because when the same model is extrapolated for 2000 years it clearly diverges from reasonable patterns deduced from temperature proxy reconstructions. Their figure is here and reproduced below


Every smart person would understand that this is another skepticalscience’s trick to fool the ignorant.

It is evident that if, as we have clearly stated in our paper, we are ignoring the secular and millennial cycles and we just approximate the natural millennial harmonic trending with a first order linear approximation that we assume can be reasonable extended up to 100 years and no more, it is evident that it is stupid, before than being dishonest, to extrapolate it for 2000 years and claim that our result is contradicted by the data. See here for extended comment by Loehle and Scafetta.

As said above in those models the secular and millennial cycles were excluded for purpose. However, I already published in 2010 a preliminary reconstruction with those longer cycles included here (sorry in Italian), see figure 6 reported below


However, in the above model the cycles are not optimized, which will be done in the future. But this is sufficient to show how ideologically naïve (and false) is the claim from skepticalscience.

In any case, the secular trending and its association to solar modulation is extensively addressed in my previous papers since 2005. The last published paper focusing on this topic is discussed here and more extensively here where the relevant figure is below


The black curves represent empirical reconstruction of the solar signature secular trending since 1600. The curve with the upward trending since 1970 is made using the ACRIM TSI composite (which would be compatible with the 60-year cycle) and the other signature uses the PMOD TSI composite which is made by manipulating some of the satellite records with the excuse that they are wrong.

Thus, until the secular and millennial cycles are accurately identified and properly included in the harmonic models, it is the studies that use the TSI secular proxy reconstructions that need to be used for comparison to understand the secular trending, like my other publications from 2005 to 2010. Their results are in perfect agreement with what can be deduced from the most recent papers focusing on the astronomical harmonics, and would imply that no more that 0.2-0.3 oC of the observed 0.8 oC warming since 1850 can be associated to anthropogenic activity. (Do not let you to be fooled by Benestad and Schmidt 2009 criticism that is filled with embarrassing mathematical errors and whose GISS modelE performance is strongly questioned in my recent papers, together with those of the other IPCC models) .

I thank Anthony for the invitation and I apologize for my English errors, which my above article surely contains.

Relevant references:

[1] Nicola Scafetta, “Testing an astronomically based decadal-scale empirical harmonic climate model versus the IPCC (2007) general circulation climate models.” Journal of Atmospheric and Solar-Terrestrial Physics, (2012). DOI: 10.1016/j.jastp.2011.12.005

[2] Adriano Mazzarella and Nicola Scafetta, “Evidences for a quasi 60-year North Atlantic Oscillation since 1700 and its meaning for global climate change.” Theor. Appl. Climatol. (2011). DOI: 10.1007/s00704-011-0499-4

[3] Craig Loehle and Nicola Scafetta, “Climate Change Attribution Using Empirical Decomposition of Climatic Data.” The Open Atmospheric Science Journal 5, 74-86 (2011). DOI: 10.2174/1874282301105010074

[4] Nicola Scafetta, “A shared frequency set between the historical mid-latitude aurora records and the global surface temperature.” Journal of Atmospheric and Solar-Terrestrial Physics 74, 145-163 (2012). DOI: 10.1016/j.jastp.2011.10.013

[5] Nicola Scafetta, “Empirical evidence for a celestial origin of the climate oscillations and its implications.” Journal of Atmospheric and Solar-Terrestrial Physics 72, 951–970 (2010). DOI: 10.1016/j.jastp.2010.04.015

Additional News and Links of Interest:

Global Warming? No, Natural, Predictable Climate Change, Larry Bell


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Nicola, Thank you for sharing your research with us here. Its because of your sharing, and then the discussions afterwards, that gives people a chance to consider the different arguments involved.

Of course, in addition to twist numerous facts, Leif has also never acknowledged in his comments the huge discrepancy between the data and the IPCC projection which is evident in the widget.
True to form, let me note that IPCC being wrong does not mean that you are right. As far as I can see, your ‘prediction’ has already failed. Of course, as you point out, you do not predict the actual detailed changes. In effect you are saying that you predict no changes at all for a long time to come. Any deviation from that ‘prediction’ is just irrelevant detail.


As a long time reader and some time poster on WUWT I find myself more drawn to those who observe and explain than those who bang away on little tin drums.
Does anyone else see the 4 year frequency of peaks in the UAH data? Looks obvious to me, but I’ve never seen this short cycle discussed.

Scafetta’s estimates are a fraction too high around his peak in 2014 – 2015. More detail asto my reasons will be on my publication at in about 30 hours from now.
REPLY: This is just repackaged “Slaying the Sky Dragon” rubbish. Cotton asked me to carry it and I’ve flat out refused. They created a “journal” to try to legitimze papers published there, which to me speaks of desperation.
Readers might want to revisit this story where Dr. Fred Singer talks about the issue:
“Climate Deniers” Are Giving Us Skeptics a Bad Name


Maybe this sounds mean, but I just can’t take it.
My equally valid geo-gravitational climate model is based on experimental evidence of the elevation change of a marble rolling on the kitchen floor. There are ups and downs due to linoleum texture, but otherwise, I predict essentially flat temperature going forward. You can repeat the experiment any time to get the next prediction. Hey, my results are better than CO2-based models.


I’d certainly quibble with this statement:
“By the way, contrary to the claim of sckepticalscience, in statistics it is 1-sigma envelope width that is used; not 2-sigma or 3-sigma.”
…since it is indeed far more common to work with a 95% confidence interval (or p< 0.05).
However, I don't think the burden of proof is to disprove the IPCC model. The model is not the null hypothesis. The null hypothesis is natural climate change and the CI or p-values should relate to the statistical test comparing the alternate hypothesis (CO2-driven change, solar-driven change) to the null hypothesis.

Dr. Scafetta,
Thanks a ton for sharing your work. Really interesting!

Scafetta’s calculation of the model means is wrong.


It seems quite clear. When the ob data moves outside the cyan area of Nicolas prediction it’s due to inter-annual climate variability due to ENSO which is unpredicted by nis model. These excursions aren’t “irrelevant”, require explanation but aren’t predictable.
maybe you need a second envelope around your cyan area which represents the potential temp change that can be induced by ENSO with a proviso that excursion into this region should be temporary and in phase with the ENSO effect on GST.

Please don’t waste your time at SKS; they can’t be confused by facts. The site applies censorship in an extreme way and it has become another echo chamber as exemplified by Joe Romm’s Climate Progress. The “Moderators” such as “Daniel Bailey” and “dana1981” are religious fanatics, deaf to reasoned arguments.
I am not surprised that your predictions are better than the IPCC’s AR4. The AR4 was published in 2007 so you have almost five years more observations than they had.
Looking ahead, the IPCC’s AR5 will be based on technical (WG1) studies due for completion in September 2013 so the IPCC will have the opportunity to “tweak” their predictions to eliminate at least part of the 6 sigma variance between their most relevant AR4 temperature scenario and current year observations.
So will the AR5 temperature predictions be more plausible than those in AR4? Having studied most of the AR5 WG1 “Zero Order Drafts” and some of the “First Order Drafts” I can assure you that unless there is a U-turn, the predictions will be no better than those in AR4. Some of the GCMs have been “tweaked” in the wrong direction (stronger influence of CO2).
If the AR5 is published in September 2014 based on current WG1 drafts, the temperature variance could easily be 8 sigma unless there is a sharp increase in global temperatures over the next couple of years. Somehow I don’t think that even the IPCC will be blind to the problem so they may be forced to choose between an “Agonizing Reappraisal” or appearing even more ridiculous.


A two to four year smooth on the HadCRUT3 would assist interpretation ….


Nicola, I will say it again: your yellow curve (lower average limit) is to high. Solar cycles 23 and 24 are too long (weak) for the anomaly to stay that warm. HadCRUT3 will be at zero anomaly until 2020.


I have no insight as to whether the presented model is correct or even founded on accurate assumptions about climatic variation but it is substantially more accurate than all the IPCC models and that makes it more interesting and potentially more useful. I’m not sure how much funding Dr. Scafetta has required to develop his model but the failed IPCC models cost at least tens of millions. I imagine the ROI when plotted as dollars spent vs. model variance from measured temp makes Dr. Scafetta’s work seem like a great investment by comparison.
The attempts by the zealots at “Skeptical”Science to minimize the failure of the IPCC models highlights the weakness of their position. The wider they try to make the error bars in an effort to stay in-bounds also makes the IPCC “projections” not very alarming.


Hoser: You raise a good point. If your linoleum floor model out performs a more complex model in terms of its ability to predict future events, then you must accept it as a more valid model. Not the answer you wanted, but testing against reality is really the only valid measure there is.
Climate modeling is a modeling exercise, not a physics problem, contrary to what some may otherwise profess. Many stochastic processes, chaotic interactions, many unknowns, etc… If you want accurate forecasts, treat it like a forecasting problem.

There will not be an anthropogenic 0.9 oC/century rise. The underlying 1,000 year trend shows no such rise and is, in fact reducing from 0.06 C deg/decade early in 20th century to 0.05 C deg/decade at present with no indication of any CO2 sensitivity at all. This rate will continue to decline until a maximum is reached 50 to 200 years from now It is very unlikely that the long term trend will increase more than 0.5 C deg / century between now and then, more likely 0.3 to 0.4 C deg./century as the sinusoidal trend starts to top out.

Doug Proctor

In 2015 the disconnect between a “moderate” IPCC projection and Scarfetta prediction will be 0.25 to 0.30 C. The global temperature will not have risen for 15 years. For a “settled” science and “certain” outcome, these facts should be terminal: CAGW is moving forward only because it is “fact”, not theory. We need to act, not understand.
If Hansen and Gore have to admit that nature, not man, has dominated the since 2000, without dropping their meme of C02, then their rhetoric must become more shrill. Like the Harold Camping of 2011, they must rise to a bluster that is impossible to misinterpret. We need to encourage them to tear their hair and clutch their chests as the days pass.
Scarfetta suggests that after 2015 the global temperatures will drop. All hail the fall! Not because I wish the temperatures to drop, because dropping temperatures are generally not good, but because there is a size limit to what even the noble gullible can swallow.
And, by the way, a moderate temp drop will only bring us back to 1965. I don’t think that 1965 was a bad time climate-wise. Of course, GISS records might tell me that we had a mini-ice-age in 1965, and I forget because I am stupid.

Robert of Ottawa

This is a model, folks. An interesting exercise in curve fitting, but, until we have a couple of thousand years of data, they are no more than pass-times, like crossword puzzles or darts.

I am not really aware of the theory and mechanisms that Dr. Scafetta is advancing, but after reading the above article, I will read his paper. The above article is very clear and effective on addressing the criticisms against it.
I note in particular that the criticisms that SkepticalScience levels are almost identical to the same accusations against Bob Tisdale’s work. Dr. Scafetta makes short work of those critcisms, and shows them to be as ridiculous as Bob did.
I look forward to reading this paper.

There are number of various pointers to falling temperatures. Extrapolation from the existing CET record, based on reconstruction of three recurring periods
assumes that all major periodic external forcing (solar, planetary etc) is in the 350 year long data record already.

Henri Masson

Thanks to Dr Scafeta for sharing his work and thoughts.
This is indeed, as mentioned in some comments, nothing more than some curve fitting exercise (mathematically a decomposition in Fourier series, obtained by looking at the Power Spectrum of the data). But this can be a very useful and promizing prediction tool. In another field, Kelvin waves have been identified in the same way and are are presently the most accurate and widely used way of predicitng tidal waves. And nobody can claim that the associated complex mechanisms are understood or satisfactory modelled, for the time being.
Predicitng is not necesserly understanding all the details…..but poliitcal decisions are based on predictions, and the last ones are better accurate if one wants to develop and implement sound policies.

Scottish Sceptic

Harmonic component?
Like the bogus Camp Century Cycles which created the global cooling scare?
Like the bogus Camp Century Cycles whose lack of predictive power forced climate searchers to look for an even bigger forcing like exaggerated CO2.
The whole nature of 1/f noise is that it appears to have cycles. Indeed, I would suggest it is better called “fractal noise” as it has the property that sections appear to repeat (almost). That is why the early 20th century warming looks like the late 20th century warming. Add them together and it appears as if we have a 50 year cycle.

Henri Masson

Another more technical point.
Dr Scafetta does not consider longer period sinusoïds (with periods of one century or more), because of some discrepencies and inaccuracies in the time series for the proxies used to reconstruct the climate over a longer period. He is right of course.
But if we add to his curves a longer period sinusoïd, we can simulate the exit from a mini-glaciation age (Maunder and more recently Dalton) as well as the medieval optimum.
In fact there are four levels of periodic phenomena
1- Milankovitch cycles (20 000, 40 000, 100 000 and 400 000 years). The IPCC recognizes this, but states the variations are too slow to be significant at the horizon of one or two generations; they are right on this point.
2- cycles with periods ranging around one or a few centuries (there is some geological evidence for a cycle of roughly 200 years)
3- the multi-decennal set on which Dr Scafetta focuses his work (9.5, 10-12, 22, 60 years)
4- short term quasi periodic phenomena El Nino, or even the moon cycles (which affect the tidal amplitudes), also mentionned by Dr Scafetta but not included in his model.
Consideirng cycles of a century or more (category 2) has an important consequence. It challenges indeed the concept of “a flat temperature, averaged over space and a period of 30 years, from which “anomalies” are deduced, which is curent practise (reference periods are1930-1960; 1960-1990 and the nexrt one will be 1990-2020).
If the true basis line is actually the ascending branch of a sinusoïd, say with a period of 200 years, (as is the case: we still come out of the Dalton mini glaciation period 1800-1830) the fact of “using a flat basis line” induces automatically a “hockey stick effect”.
Another consequence could be (according to the phase of this 200 years sinusoïd) that we reach the maximum of this sinusoïd, which could explain the leveling of temperature since 2000 and even the decline observed during the very recent years. This means that the anthropogenic contribution could well be even less than what has been estimated by Dr Scafetta (already 2.6 smaller than the estimations of IPCC°.

Henri Masson

A third theoretical comment this time.
The climate system is known to be (mathematically) complex and non linear (otherwise oscillations would not exist), even chaotic (dynamical system): the temperature oscillates between a few attractors (glaciation, tempered climate, and even probably one or two intermediate states).
In such systems, rather independent periodic oscillators (resulting each from the parallel setting of a (thermal) resistance and a (thermal) capacity) can get synchronized by a LEGION mechanism (see Wilkipedia): If the loading of the capacitance is slower than its discharge, and if each time the threshold level for discharge is reached by anyone of the oscillators, it sends a signal (a small step increse in charging), after a while the different oscillators will synchronize. This mechanism has been identified as the working principle of information transmission through neurones and it explains also the synchronized luminescence of some insects (light worms). It can be descibed as a kind of “intermittent mutual and exhaustive symetric causal link” between the different oscillators. In simpler words, I compare it to a “spaghetti bowl”: If you pull anyone of the strings, the whole bowl vibrates, without having any fixed causal link between the strings.

Stephen Richards

Greg says:
March 11, 2012 at 9:20 pm
NO Greg. Trenberth tried that one. Sorry it doesn’t work. The null hypothoses is that CO² Controlles the climate.


the extension of your model back for 2000 years is nonsense for the reasons well explained by yourself. But l am wondering whether any other attempts for a back projection of that length were made, in particular were IPCC used for any backprojection?


Very interesting article.
There has been much written over the past few years with regards to various natural oscillations effecting the climate. Bringing these together has been long overdue.
Vukcevic has produced a lot of very interesting graphics over the past that I always check out.
Scafetta, Vukcevic, and others are showing pieces of a puzzle that should have been shown years ago if proper research had been done with regards to climate issues.
The chase for the ’cause’ of any minor temperature change due to CO2 has hijacked much research that could have been better invested. The 60 year cycles coupled with other longer cycles could have very serious consequences in our current society if cooling is pronounced and rapid.
If Scafetta’s suggestions turn out to be correct and the temp only flattens out over the next decade or two and we stop the renewable madness, society should be OK. If the temps fall considerably and we continue with the current energy policies and green mandates in transportion then colder winters and more snow will have devastating consequences. It could be like getting caught in a blizzard while wearing your bathing suit. Where I live 6 ” of snow shuts everything down. Those of us with a 4wd have to baby sit those without. Electric cars anyone?
I hope Scafetta is correct with the leveling of temps for two reasons. One, maybe it will stop the green madness. Second reason, maybe the temps will not plumment. I fear the latter.

Does anyone else see the 4 year frequency of peaks in the UAH data? Looks obvious to me, but I’ve never seen this short cycle discussed.
It is an imprint of the AMO on the global temperatures (~4-5 year is a second harmonic of the fundamental around ~9.5 years), it is well known, its origins aren’t, but many attribute it to the luni-solar tidal oscillations. Here you can see
clearly all the way through the global temperature records.


Looks like “climate change” is gonna get very very boring, even for the next 2 generations LOL

Espen says:

Does anyone else see the 4 year frequency of peaks in the UAH data? Looks obvious to me, but I’ve never seen this short cycle discussed.

That’s the effect of El Niño/La Niña you’re noticing.

Nikola Milovic

For all the discussants
Strangely enough, in most cases, as evidence for the existence of something, using data from previously published sources, which are often based on unfounded or erroneous model assumptions
How can a body can heat up at all?
Just bringing some energy: either direct heat or other types of energy in various ways can be transformed into heat energy.
For Earth, this second variant of the electro-magnetic energy (magnetic fields) is transformed into heat in a certain way, which should be made.
Earth nothing else can millions of years to heat and cool than this type of energy.
What is the most important thing in all this?
We need to find:
fundamental causes of these phenomena and the mechanism of transformation of the entire system.
Sunspot cycle and the reconnection of magnetic poles of the Sun are the main causes of these phenomena.
How this occurs all-seeing, d is currently unknown to science.
I have no need or possibility of mathematical models of real or unfounded assumptions, on which I set up a claim.
I have some mathematical confirmation regarding the cause of the above phenomena.
There are almost countless cycles and sub-cycles in all time periods (past, present and future).
To do this draft and realise as a program, it needs a lot of work and resources that can provide only a powerful institutions like NASA or the U.S. Government.
Who among you has the ability and interest to assist in this you have my e-mail.


I just can’t make myself believe that this cycle-based prediction has any better predictive skill than IPCC models. My opinion is, neither has any. Both come from assumption that certain properties will continue their trend as it is up to now, they only differ in which properties do they concentrate on. And while 10 year old models are already noticeably diverging from the reality, the cyclic prediction will IMO take another 15-20 years before it will start to significantly diverge as well.
There’s no dispute many natural changes come in cycles. But these real natural cycles undergo changes as well, they may change in amplitude and some may change in frequency as well – for example I bet atlantic oscillation had smaller amplitude and higher frequency way back when America was closer to Africa/Europe than it is today. Of course you can express these changes using cycles as well, the problem is these new cycles are not natural already and they’re indistinguishable from artifacts brought in by the analysis.

Gail Combs

Dr. Scafetta states:
“Another criticism, in particular by skepticalscience, regards the width of the boundary (green area in the widget) that I used, They have argued that
“Most readers would interpret the green area in Scafetta’s widget to be a region that the IPCC would confidently expect to contain observations, which isn’t really captured by a 1-sigma interval, which would only cover 68.2% of the data (assuming a Gaussian distribution). A 2-sigma envelope would cover about 95% of the observations, and if the observations lay outside that larger region it would be substantial cause for concern. Thus it would be a more appropriate choice for Scafetta’s green envelope.”

From my sketchy and ancient statistics it would seem they are trying to use a 2-sigma envelope for individual data points and then apply it to an average. However the distribution of a moving average will always have less variation than the distribution of the individual points.

Congratulations to Nicola for standing up to the insane logic of the IPCC and their followers that include Leif.
Accurate data stands up to rhetoric over the longer term.

Gail Combs

Note added to my above post. You can tell the Warmists are using individual points because every time there is a hot day they scream it is proof of CAGW.

Henri Masson

One more comment on sinusoïds and linear trend lines:
The “least square” linear trend line for a sinusoïd is a perfect horizontal (and does not provide so much information on the amplitude and period of the sinusoïd).
But, when the slow “basis line” sinusoïd exhibits a period close to (but not exactly equal to) the extend of the “measurement window” of the time series, anything can happen with the slope of the “least square” straight line, according to the point “along the phase” of the sinusoïd where you start the measurement window (initial date) and the point where you close the window (final date considered): the “least square” linear trend line can indeed be horizontal or presenting an increasing or a decreasing slope. The IPCC did exactly this on an “increasing portion of the 200 years sinusoïd, leading them to the fallacious conclusion that there is a temperature increase of (a fraction of) a tenth of a degre C per year. Actually they have detected nothing else than a “border effect” of their measurement window.
I would be delighted to hear Dr Scafetta comments on this remark, and also on my previous ones. I hope my comments will reinforce his statements and allow him to make the real breakthrough he deserves for his work.

Gail Combs

Stomata says:
March 12, 2012 at 3:10 am
Looks like “climate change” is gonna get very very boring, even for the next 2 generations LOL
Stomata, shame on you! Especially with that name. To farmers, especially in Canada and Russia that is anything but boring. A consistent drop in temperature can wipe out borderline crops areas. The freezes in Florida destroying the citrus fruit crops is a case in point.
“….Thirty odd years ago, Middle Florida produced practically all of the citrus fruit grown in Florida, over three-quarters of the entire crop being shipped from Ocala, the seat of Marion County. The industry at that time was in a most prosperous condition. Money was being made on every side, and that money was being reinvested in new and larger groves. Then came the great freeze of ’95, and in a single night, as it were, the whole citrus industry of Florida was wiped from the map, nearly every grove being destroyed and over four million boxes of luscious fruit being killed on the tree.
Never in history, perhaps, did any industry receive a severer blow than this, and it was a blow that shook to its foundations the whole industrial fabric of the state, for Florida…”
As several of us keep saying warm and wet is better than cool and dry. More CO2 that makes plants grow faster with less water is better than borderline plant starvation which is what 250 ppm of CO2 actually is.
WHEAT: “…The CO2 concentration at 2 m above the crop was found to be fairly constant during the daylight hours on single days or from day-to-day throughout the growing season ranging from about 310 to 320 p.p.m. Nocturnal values were more variable and were between 10 and 200 p.p.m. higher than the daytime values….”
Note that the plants are dropping the CO2 to 310 + 5 ppm and not down to 250 ppm. The following shows just how fast the plants will gobble up available CO2.
CO2 depletion in a greenhouse
“….Plant photosynthetic activity can reduce the CO2 within the plant canopy to between 200 and 250 ppm… I observed a 50 ppm drop in within a tomato plant canopy just a few minutes after direct sunlight at dawn entered a green house (Harper et al 1979) … photosynthesis can be halted when CO2 concentration aproaches 200 ppm… (Morgan 2003) Carbon dioxide is heavier than air and does not easily mix into the greenhouse atmosphere by diffusion…” Source

Gail Combs

Henri Masson says:
March 12, 2012 at 1:59 am
A third theoretical comment this time.
The climate system is known to be (mathematically) complex and non linear (otherwise oscillations would not exist), even chaotic (dynamical system): the temperature oscillates between a few attractors (glaciation, tempered climate, and even probably one or two intermediate states).
In such systems, rather independent periodic oscillators (resulting each from the parallel setting of a (thermal) resistance and a (thermal) capacity) can get synchronized by a LEGION mechanism (see Wilkipedia): If the loading of the capacitance is slower than its discharge, and if each time the threshold level for discharge is reached by anyone of the oscillators, it sends a signal (a small step increse in charging), after a while the different oscillators will synchronize….
So if the loading capacitance (the Sun) is slower than its discharge mechanism (Ocean oscillations) you could see the changes in the SST that we see as ~ 60 year cycles and also as ENSO.
And we come back again to “Its the Sun Stupid!” The fact that TSI does not have a large variation does not matter.

matt v.

Making forcasts is a difficult process. We know that IPCC’S forecasting record is off.Paul Hudson’s blog reported that the MET Office has been wrong for about 11 years now being high most of the time . This was the case again in 2011. Their forcast for 2012 seems no better as they are again predicting 2012 to be warmer than 2011. Too much emphasis on CO2 impact? Girma Orssengo’s simple mathematical overlay model using the historical Hadcrut3 global mean temperature data seems to be the only one that has got it about right recently. His model predicted the GMTA to be 0.375 C for last year . The actual was about 0.347C . He is predicting a drop again this year and a steady decline to about 2030. Persoanlly I think the actual global temperature anomaly trend as opposed to isolated years [which can vary] will go below your yellow curve and stay below it . Ocean cycles and solar trends seem to support this .I dont think we will have warming to 2015/2016. I dont think that “the climate will likely stay steady until 2030/2040” as your written material states . I think temperatures will drop more than stay steady. I see nothing in the ocean’s cycles or the lagged solar signals or future solar predictions to indicate global warming to 2015 or a steady climate to 2030. Your prediction of a warming 0f 0.3C to 1.2 C by 2100 seems reasonable, but that is too far away to call at this time . Your numbers are a much improvement over IPCC’S figures

Greg says:
March 11, 2012 at 9:20 pm

However, I don’t think the burden of proof is to disprove the IPCC model. …

Indeed, IF the “policy makers” were viewing the IPCC model in a proper, skeptical scientific manner, we probably wouldn’t even be discussing it. However, they are not – they use the “wide-eyed, boy looking in a candy shop window” view followed by “we are all gonna die!”. The more that is done to show that the model does not show what is happening and it is not a good predictor of what will happen, the better.
Dr. Scafetta shows that the IPCC model does not agree with observations while the IPCC model’s supporters attempt to hide the decline (haven’t we heard that before?) of the observed temps as these observed temps diverge from their projection. I know, it is a travesty, But in real skeptical science, life doesn’t imitate the art of deception practiced by the IPCC crowd.
Dr. Scafetta also provides an alternative “projection/prediction” possibility. Whether it is reasonable or not does not change the fact that the IPCC model does not track well with the observed temperatures.

Gail Combs says:
March 12, 2012 at 5:20 am
Note added to my above post. You can tell the Warmists are using individual points because every time there is a hot day they scream it is proof of CAGW.

And, every time there is a cold day they scream it is proof of climate change caused by CAGW by CO2.


Leif Svalgaard says:
March 11, 2012 at 8:36 pm
“In effect you are saying that you predict no changes at all for a long time to come. Any deviation from that ‘prediction’ is just irrelevant detail.”
Eh? How did you come to that conclusion from this article? I thought we were trying to determine decadal trends, not annual variability. Therefore any annual deviation from the prediction is meaningless unless it is part of something that persists for long enough to drag the trend away from the moving average. What’s wrong with that?
It is perfectly plausible to suggest that the climate is subject to the same kinds of natural oscillations that exist in many other complex systems. Dr Scafetta is suggesting one such characterization, provided reasoning for it, and giving a falsifiable prediction based on it. What’s wrong with congratulating him on his hard work, making some suggestions on things he might have missed, and then checking back in a few years time to see how the prediction is getting on?
If the temps veer wildly to left and give us 4 or 5 years in line with where the IPCC said we should be at, or glaciers appear in Muswell Hill (London) again, we’ll know he was wrong. He has even given you a very low error range you could hold him to.

The yellow curve is the one that will provide the best match. The 0.93/century anthro add-on is an unnecessary fudge.


As far as I can tell, 2-sigma (95%) is a standard confidence and prediction interval in most scientific fields. Soft sciences like psychology may use lower, large-scale sciences like physics may use higher.

Agnostic says:
March 12, 2012 at 6:07 am
“In effect you are saying that you predict no changes at all for a long time to come. Any deviation from that ‘prediction’ is just irrelevant detail.”
Eh? How did you come to that conclusion from this article?

The first point is clear as a straight horizontal line with no trend falls within the cyan error band. The second point is Scafetta’s excuse for deviations.

Agnostic says:
March 12, 2012 at 6:07 am
If the temps veer wildly to left and give us 4 or 5 years in line with where the IPCC said we should be at, or glaciers appear in Muswell Hill (London) again, we’ll know he was wrong.
but if there is no change at all, we cannot conclude that he is right as there could be many reasons for no change. My new and improved phenomenological model [that the climate mirrors the mass of my old shoes] also predicts no change at all.


To Leif Svalgaard
“but if there is no change at all, we cannot conclude that he is right as there could be many reasons for no change. My new and improved phenomenological model [that the climate mirrors the mass of my old shoes] also predicts no change at all.”
This argument would be fine if your basing your argument on the fact you know completely how the climate system works.
If however you admit you don’t fully understand the climate system then any model no matter how outside the normal it may be as long as it predicts correctly is fundamentally the best model to use.
If your old shoe model works then it is still the best model… which says more about the failure of the other models then it says about the “process”/”look” of yours.
If someone reading tea leaves can predict the future out years and be right then the other predictions made out into longer time periods can also be weighted more heavily as being the most likely outcome.
Only when we know how exactly a system works and thus can predict it 100% can one claim that the old shoes model is wrong.

Leif, I have already explained where your argument is wrong. You need to separate the time scales. You are looking at the fast ENSO oscillations (time scale is a few years) while the model is limited to the dacadal and above time scale patterns. If you do not understand this, I do not know what I can do. Try to use a paper and draw some picture with two superimposed oscillations with period let us say 3 yeas and 20 years. You may realize that even when the 20 year cycle is warming, the superposition of the two cycles may actually momentarily cool because the 3-year cycle was momentarily cooling.
Come on, Leif. It is not difficult to understand the point, just focus a little bit, OK?
Perhaps, can some readers help Leif?
Some other readers have addressed the problem of the 0.9 C/century trend that I estimated for the anthropogenic component. You need to read my paper to understand this point well.
The estimate is based on a set of conservative hypotheses, the real anthropogenic trend may be less. That is why I also plotted the other yellow curve, which ignores it.
Essentially, that 0.9 C/century trend comes from the period 1970 to 2000 where this component of the model is calibrated, and it is the left over warming trend after that the warming coming from the cyclical component is detrended from the data. That left over warming trend is conservatively interpreted as “net anthropogenic component”.
However, as I clearly stated in the paper, part of that left over warming trend may be also due to other natural cycles not taken into account in the harmonic model, or to UHI and LUC effects left in the data, to math errors in processing the data etc. in addition to be a combination of anthropogenic GHG (warming) and aerosol (cooling).
So, there might be deviation from this 0.9 C/century warming trending as other cycles are identified as well as better algorithms to clean the data from UHI and LUC (and other things) are implemented. That is the reason why I also added the yellow curve estimate without that trending. So, the temperature may well fall between the black and the yellow limits
Some readers are also insisting about the 2-sigma width. They are missing the point. The issue is that physical models must be scientifically validated to be physically acceptable. To be validated a proposed model needs to have an error bar smaller than the amplitude of the detectable data patterns. A explained above, the error bars associated to the IPCC models as acknowledged by skepticalscience is far too larger that the amplitude of the temperature patterns, so those models cannot be validated according to the scientific method.


Anyone who has seen the temperature graph [1] of from the Vostok station ice core data can plainly see that the climate is always changing. Indeed, on average the climate is so cold that much of the arable land on earth is covered in snow and ice. The essential issue then must be to what extent is human activity perturbing the climate in a way that is harmful in a meaningful way?
To that question I make two observations:
1) The case that humanity is changing the climate for the worse has yet to be made. First, nobody has put forth any data as to what the ideal climate should be. So how can we evaluate the present climate and any human-caused changes?
2) Too many people, both in science and the media are clearly in a rush to impose a cure to solve a problem when we have yet to fully define it. Further, every one of those solutions involve bigger government, less personal freedom and less prosperity. One gets the impression that climate change is merely a horse being ridden to accomplish an ideological goal.
It is on the last point that I am most concerned. Already advocates of climate change have seriously proposed that those who dispute their thesis should be treated as criminals and their ability to object be suppressed by the State, by which they mean, by coercion and the threat of deadly force if necessary. Although polite people will never say it, the raw truth is that whenever someone proposes to use the State to effect their personal policy preference, they are willing to send men with guns to deal with anyone so foolish or resolutely opposed as to refuse to comply.
I have seen this attitude before. It resulted in the deaths of millions in the previous century. It tells me more than I need to know about the real agenda here.

Nicola Scafetta says:
March 12, 2012 at 7:40 am
I do not know what I can do.
That just about sums up the whole argument.