A skeptic lacking skepticism: Fritz Vahrenholt

Fritz Vahrenholt and Sebastian Lüning, both from RWE (1), have published a book "Kalte Sonne - Warum die Klimakatastrophe nicht stattfindet", which claims that greenhouse gases would play only a minor role in changing climate, while solar activities would be dominant. He goes so far to explicitly predict a cooling – of 0.2 to 0.3 C until 2035. “That the sun and its impact on Earth will present us cooler times in the first half of the present hundred years, is … certain.” (my translations; p. 35)


The main author is deeply disappointed by the IPCC. He responds in an interview with WELT online on 7 February 2012 to the question

Welt Online: You have supported the claims oft the IPCC for many years. Now, you are publishing a book, which questions the main stream scientific explanation of climate change. What caused you to change your position?

Fritz Vahrenholt: Yes, I was an active supporter of the CO2-theory. But then I had two key experiences, which caused me to rethink my position.
One took place, when I was invited in February 2010 to act as scientific reviewer of the IPCC report on renewable energies. I found that this work was not really done according to scientific principles. The report was full of errors. In the end, it was a representative of Greenpeace who was allowed to do the editing of the final version. The result was the senseless claim that 80% of the total energy demand could be covered by renewables.
This event surprised me. What happened in this panel, could possibly also take place in other IPCC panels, I thought. Most members of the 34-person UN-secretariat are from the south, such as Cuba, Sudan, Madagascar, Iran or China. These countries are interested in financial transfers. Previously I had thought that scientists would meet and discuss. No, these are delegates of – actually not democratically structured – states. They represent interests and influence emissions of greenhouse gases per capita and year.

Welt Online: And the second key experience?

Vahrenholt: We at RWE Innogy were confronted with a significant reduction of wind and the resulting energy products. I examined this phenomenon scientifically and found that this had nothing to do with CO2 and global warming but that it was due to natural climate processes. The sun plays an important role.

The publication of the present book made a big splash in German media, which is not surprising, as Fritz Vahrenholt was an icon of the German green movement, best known for his co-authorship of publication of the landmark book “Seveso ist überall. Die tödlichen Risiken der Chemie“ from 1980. On the web-page of the present book Klimazwiebel and myself was originally falsely listed as supporters of an explanation by natural variations (2). The daily newspaper taz invited me to join the current “controversy of the week” (Streit der Woche)– about “Is it allowed to listen to climate skeptics?” ("Darf man Klimaskeptikern noch zuhören?"). The background of this issue, I was told, was the debate generated by Vahrenholt. (3)

What Vahrenholt presents is a complete explanation of the climate variations, referring to handful of scientists. This explanation is highly complex, with many challenging details, which can hardly be verified by a single person, scientist or lay-person. The interesting detail is that Fritz Vahrenholt is really certain about this “explanation”. Not a bit skeptical. He is not discussing, which observations would falsify his explanation; he is not examining what a failure of single elements of his full system would mean for the validity of his explanation. There may be valid points in his analysis, but when he comes closer to areas, which I personally have studied, errors emerge, and when I speak to other scientists they say the same for their fields of competence. It seems that Fritz Vahrenholt and his coauthor Sebastian Lüning have simply cherry-picked – what is what they criticize their opponents for.

What we see here is a transformation of an alarmist to a skeptic, who replaces the main message without changing attitudes, methods, claims-making and lack of skepticism against own positions and people, who support the wanted outcome of the analysis. He has not changed in his need to have opponents, or maybe better: enemies. He is a politician, who uses populist methods, and has no idea what science consists of. I consider him and his coauthor as honest people; they really believe what they say, they are seriously and honestly upset about what they see as a conspiracy.

Vahrenholt's demand that alternative explanation systems of the observed climate changes and of expected future changes need to be studied, is entirely legitimate; more resources should go into the scientific inquiry about alternative explanations, but they should be studied with the same scrutiny as the greenhouse-gas based explanation, which has been examined carefully by very many different scientists and disciplines. But to present the solar-explanation system as certain truth, is simply irresponsible. What is needed is skepticism, which should not be used as an excuse of not deciding about policies.

But I was really surprised, and personally disappointed, when Fritz Vahrenholt referred to the reduced harvest of regional wind energy in recent winters as a surprise and an argument against the reality of man-amde climate change. How could he have believed in a steady increase of windiness in Northern Germany in the early decades of the 21st century because of increasing greenhouse gas levels? Obviously, somebody told him so, but who may that have been? We know that windiness is undergoing massive decadal variations, and we know that an increase of windiness in the coming century is not a consistent part of the scenarios  (cf. BACC report 2008, Hamburger Klimabericht 2010, ongoing HGF Klimaatlas)  which would be overlaid by significant decadal variations. Actually, we prepared a diagram for Fritz Vahrenholt showing the variation of annual distributions of wind near Alpha-Ventus in the past 50 years, which demonstrated that there is no systematic change but mere variations. (4)

The appearance of Fritz Vahrenholt as a "skeptic" in the public limelight  is an interesting case for skeptogenesis, why people become skeptics. In  the interview above he spells out one motive - the feeling that he may have been betrayed by dominant scientists, who speak science but mean specific policies.

----
Corrections/modifications per 13. February 2012

(1) I wrote originally, both would be from RWE Innogy, but comment 73 clarified that while FV is from RWE Innogy, but SL from RWE DEA.

(2) The listing of Klimazwiebel was later corrected after we asked SL top do so.

(3) I wrote a comment as requested by taz, but taz decided that my comment would not ally deal with the question posed, see #73.

(4) Originally I had this sentence: "He did not even acknowledge receiving this diagram." - Fritz Vahrenholt has complained that he did acknowledged receiving the document; I can not remember this, but I am not 100% sure about this. Therefore I am withdrawing this sentence.