A New Millennial Global Surface Temperature Reconstruction

By Andy May

Nicola Scafetta has written a new paper (Scafetta, 2021) in Atmosphere on a new millennial surface temperature reconstruction. This is his latest “what if the models are accurate?” analysis. Scafetta’s idea is, let’s assume a model is correct, what are the implications?

Previously, he examined the PMOD solar model, by assuming it was correct and the Sun is invariant long-term, does this make sense? Another example, if we smooth through the urban heat island effect (UHI), do we eliminate it, or just smear it out, so the data looks better, but is just as inaccurate? In the latter post, on UHI, I wrote:

“Relative to 1940 to 1960, the original HadCRUT curve shows 0.59°C of warming and 0.48°C using Scafetta’s corrections. The UAH record shows 0.44°C. The CMIP5 climate models show 0.78°C of warming.

It is possible, according to Scafetta’s correction, that non-climatic biases may have contributed a fifth of the reported HadCRUT global warming since 1940-1960. It is also possible that the CMIP5 climate models may overestimate warming by a third. These are significant problems.”

Computer models have a downside. They can be used by those on the other side of the debate. If they lead to absurd or inconsistent conclusions, they make you look foolish. What if Scafetta assumed that the HadCRUT recent temperature record is correct? Then he further assumes that the CMIP5 (Coupled Model Intercomparison Project Phase 5) ensemble mean is correct, what does this mean for past temperatures? Do we find inconsistencies?

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Climate Model Failed

By Andy May

On January 22, 2021, John Christy presented a new online talk to the Irish Climate Science Forum. The talk was arranged by Jim O’Brien. A summary of the presentation can be read at clintel.org here. In this post we present two interesting graphs from the presentation. These compare observations to the IPCC Coupled Model Intercomparison project 5 climate models (CMIP5, 2013) and CMIP6 (current set of IPCC models) climate model projections.

Figure 1. CMIP5 models versus weather balloon observations in green. The details of why the models fail statistically can be seen in a 2018 paper by McKitrick and Christy here.

The next graph compares the newer CMIP6 models to both the weather balloon data (light green) and the weather reanalysis data (dark green).

Figure 2. CMIP6 models versus weather balloon data in light green and weather reanalysis data in dark green.

The difference between the models and the observations is statistically significant and shows that the models have been invalidated. It is also significant that the CMIP6 spread of model results is worse than the CMIP5 spread. Thus, the newer models show less agreement to one another than the previous set.

Wind or Eagles?

Wind turbines are not only ugly, they are also dangerous for Eagles and other large birds. Takes a look at this video. Those blades can travel at 180 mph at the tips!


Adaptation is more profitable than mitigation

Clintel.org has just issued a nice press release about the idea of preparing to adapt to climate changes, rather than the more controversial idea of destroying the fossil fuel industry in the hope that reducing CO2 emissions will somehow make the climate better.

So far we have been unable to measure the influence of additional CO2 on the climate, although some think the impact is somewhere between 1.5 degrees and 4.5 degrees per doubling of the CO2 concentration. We cannot even be sure of that, because there are credible estimates that are less than one degree.

So, it seems reasonable to spend our hard-earned money adapting to whatever happens. Adaptation works if the changes are natural or man-made. The article is by Guus Berkhour and Marcel Crok of The Netherlands, where they understand adaptation better than most countries. Their dikes have a flooding probability of 1 time in 10,000 years.

Read the press release here.

A New Look at the Urban Heat Island Effect

By Andy May

Nicola Scafetta has just published a new paper in Climate Dynamics examining evidence of the urban heat island (UHI) effect (Scafetta, 2021). The paper is not paywalled and can be downloaded here. In summary, Scafetta shows that part of the recent warming shown in the HadCRUT 4 global temperature record may be due to the UHI effect. He uses an analysis of diurnal maximum (Tmax) and minimum (Tmin) temperatures, climate model output, and a comparison of sea surface temperatures (SST) to land temperatures to estimate the possible influence on the HadCRUT 4 record.

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The Rational Climate e-Book

By Andy May

Patrice Poyet has just published a new 431-page eBook entitled, The Rational Climate e-Book, it is free to download here. Dr. Poyet studied geochemistry, remote sensing, and computer science at Ecole des Mines de Paris / Nice University. He received his doctorate in 1986. As an expert computer modeler, he spends much of the book evaluating climate computer models and uncovers their often-unstated underlying assumptions.

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The CO2 Kink; Firn to Ice Transition

Guest Post by Renee Hannon


This post examines CO2 data collected in Antarctic firn and its journey as firn transitions to ice where CO2 is eventually trapped in bubbles. Atmospheric gases within the firn and trapped in bubbles are smoothed due to gas mixing processes with depth and time. The bubble trapping zone, also known as the Lock-in-Zone (LIZ), is a mysterious thin interval where CO2 concentrations decrease significantly with depth creating a kink in CO2 concentrations.

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May/Middleton: Rebuttal to Geological Society of London Scientific Statement on Climate Change

Guest essay by David Middleton and Andy May

A pdf version of this post can be downloaded here.

The Geological Society of London recently published a statement on climate change:

Geological Society of London Scientific Statement: what the geological record tells us about our present and future climate

Geologists Andy May and David Middleton have spent the past few days reviewing the Geological Society of London Scientific Statement and have assembled a rebuttal to some of the more questionable items in the paper.

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Michael Mann’s 2008 Reconstruction

By Andy May

In my last post, it was suggested that Michael Mann’s 2008 reconstruction (Mann, et al., 2008) was similar to Moberg’s 2005 (Moberg, Sonechkin, Holmgren, Datsenko, & Karlen, 2005) and Christiansen’s 2011/2012 reconstructions. The claim was made by a commenter who calls himself “nyolci.” He presents a quote, in this comment, from Christiansen’s co-author: Fredrik Charpentier Ljungqvist:

“Our temperature reconstruction agrees well with the reconstructions by Moberg et al. (2005) and Mann et al. (2008) with regard to the amplitude of the variability as well as the timing of warm and cold periods, except for the period c. AD 300–800, despite significant differences in both data coverage and methodology.” (Ljungqvist, 2010).

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Changing Climate Debate History

By Andy May

While researching my next book, I found a bit of interesting deception on the Intelligence Squared web site. This is the organization that hosted the famous March 14, 2007 global warming debate on the motion “Global Warming is not a Crisis.” Debating in favor of the motion were the late Michael Crichton, Professor Richard Lindzen (MIT, now emeritus), and Professor Philip Stott (University of London, emeritus). Against the motion were Dr. Brenda Ekwurzel of the Union of Concerned Scientists, Dr. Gavin Schmidt of NASA, and Professor Richard Somerville of the Scripps Institution of Oceanography.

The debate was held at the Asia Society and Museum in New York City. Their auditorium holds 258 people and, I presume, every seat was filled. The audience was polled on the assertion before the debate and after. According to the verbatim transcript of the debate (one of the tabs on the Intelligence Squared link above), moderator Brian Lehrer, announced the results at 1 hour 37 minutes:

“And now the results of our debate. After our debaters did their best to sway you…you went from, 30% for the motion that global warming is not a crisis, from 30% to 46%. [APPLAUSE]


Against the motion, went from 57% to 42%… [SCATTERED APPLAUSE, MOANS] And “undecided” went from 13% to 12%. The hardcore ambivalent are still among us. [LAUGHTER] So, in terms of opinion change, those in favor of the motion, have carried the day, congratulations to the team for the motion.”

You can hear the debate and the results on an NPR recording as well.

Gavin Schmidt was intensely embarrassed at their clear defeat in the debate. As Anthony Watts wrote in 2018, eleven years after the debate, Schmidt was so demoralized and defeated he still would not appear on stage with skeptical scientists, like Dr. Roy Spencer. Schmidt reportedly said debates are not worthwhile, regardless of the outcome. This is quite shocking to hear, debate is at the heart of scientific research. If you will not debate your points, you are not doing scientific work.

As you can probably imagine, I was nearly knocked to the floor when I clicked on the Intelligence Squared tab for the debate results on 28 December 2020. This was after I had listened to the debate and read the transcript. Under the tab on December 28 and still there January 6th, I read the winner, post-debate, was Against the motion, by 89%! Someone with access to the Intelligence Squared web site had radically changed the results from a win for the climate skeptics to a win for the alarmists. You may still be able to see this when you go to the web site. I wrote to them about this error December 28, and have received no answer.

There is certainly no excuse for lying about the results of this famous debate, but someone did.