Knud Jahnke and Rasmus Benestad

After having watched a new documentary called the 'Cloud Mystery' - and especially the bit about the galaxy (approximately 2 - 4 minutes into the linked video clip) - we realised that a very interesting point has been missed in earlier discussions about 'climate, galactic cosmic rays and the evolution of the Milky Way galaxy.

It is claimed in 'The Cloud Mystery', the book 'The Chilling Stars', and related articles that our solar system takes about 250 million years to circle the Milky Way galaxy and that our solar system crosses one of the spiral arms about every ~150 million years (Shaviv 2003).

But is this true? Most likely not. As we will discuss below, this claim is seriously at odds with astrophysical data.
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Does climate sensitivity depend on the cause of the change?
Can a response to a forcing wait and then bounce up after a period of inertness?
Does the existence of an 11-year time-scale prove the existence of solar forcing?
Why does the amplitude of the secular response drop when a long-term trend is added?
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Last week, a Norwegian official-looking - and in my view - climatesceptic website praised Eigil Friis-Christensen from the Danish space center (featuring in the Great Global Warming Swindle) and hailed him for having given the best speech ever in the annual Birkeland seminar organized by Norwegian Academy of Science and Letters (NASL). There were rumours of controversy behind the scene before the seminar, as the NASL is regarded as a prestigious body in Norway.

Furthermore, Svensmark and Friis-Christensen have written a response (title 'Reply to Lockwood and Fröhlich – The persistent role of the Sun in climate forcing'; DNSC Scientific Report Series 3/2007) to a recent paper by Lockwood and Frohlich (LF2007). In this response, they state ’… [LF2007] argue that this historical link between the Sun and climate came to an end about 20 years ago'. Another quote from their response is ‘Here we rebut their argument comprehensively’. So the cosmic ray theory isn’t quite dead after all?

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We are forever being bombarded with apparently incredible correlations of various solar indices and climate. A number of them came up in the excoriable TGGWS mockumentary last month where they were mysteriously 'improved' in a number of underhand ways. But even without those improvements (which variously involved changing the axes, drawing in non-existent data, taking out data that would contradict the point etc.), the as-published correlations were superficially quite impressive. Why then are we not impressed?

To give you an idea, I'm going to go through the motions of constructing a new theory of political change using techniques that have been pioneered by a small subset of solar-climate researchers (references will of course be given). And to make it even more relevant, I'm going to take as my starting point research that Richard Lindzen has highlighted on his office door for many years:
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By William and Gavin

On Thursday March 8th, the UK TV Channel 4 aired a programme titled "The Great Global Warming Swindle". We were hoping for important revelations and final proof that we have all been hornswoggled by the climate Illuminati, but it just repeated the usual specious claims we hear all the time. We feel swindled. Indeed we are not the only ones: Carl Wunsch (who was a surprise addition to the cast) was apparently misled into thinking this was going to be a balanced look at the issues (the producers have a history of doing this), but who found himself put into a very different context indeed [Update: a full letter from Wunsch appears as comment 109 on this post]

So what did they have to say for themselves?
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In a recent issue of the journal Astronomy and Geophysics (A&G), Henrik Svensmark coined a new term: 'cosmoclimatology' . I think 'cosmoclimatology' is a good and refreshing name for anything combining our cosmos with our climate. However, all other aspects of the article I found very disappointing. We have already covered most of these topics before, but the A&G articles provides us with some new aspects to discuss. Furthermore, Svensmark is the Director for Center for Sun-Climate Research, Danish National Space Center, and therefore influential. He is also the co-author of a recent book with Nigel Calder that received some attention. Furthermore, a laboratory experiment of his also managed to make some headlines. It seems that solar forcing is one of the sceptics' last trenches in the debate about climate change. In my view the A&G paper therefore merits a comment as long as the same old and worn arguments resurface without discussing misgivings from the critics.

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As a prelude to a new book, Nigel Calder (who was the editor of New Scientist for four years in the 1960s) has written an op-ed for the Times (UK) basically recapitulating the hype over the Svensmark cosmic ray/climate experiments we reported on a couple of month ago (see Taking Cosmic Rays for a spin). At the time we pointed out that while the experiments were potentially of interest, they are a long way from actually demonstrating an influence of cosmic rays on the real world climate, and in no way justify the hyperbole that Svensmark and colleagues put into their press releases and more 'popular' pieces. Even if the evidence for solar forcing were legitimate, any bizarre calculus that takes evidence for solar forcing of climate as evidence against greenhouse gases for current climate change is simply wrong. Whether cosmic rays are correlated with climate or not, they have been regularly measured by the neutron monitor at Climax Station (Colorado) since 1953 and show no long term trend. No trend = no explanation for current changes.

Sometimes on Realclimate we discuss important scientific uncertainties, and sometimes we try and clarify some subtle point or context, but at other times, we have a little fun in pointing out some of the absurdities that occasionally pass for serious 'science' on the web and in the media. These pieces look scientific to the layperson (they have equations! references to 19th Century physicists!), but like cuckoo eggs in a nest, they are only designed to look real enough to fool onlookers and crowd out the real science. A cursory glance from anyone knowledgeable is usually enough to see that concepts are being mangled, logic is being thrown to the winds, and completetly unjustified conclusions are being drawn - but the tricks being used are sometimes a little subtle.

Two pieces that have recently drawn some attention fit this mould exactly. One by Christopher Monckton (a viscount, no less, with obviously too much time on his hands) which comes complete with supplematary 'calculations' using his own 'M' model of climate, and one on JunkScience.com ('What Watt is what'). Junk Science is a front end for Steve Milloy, long time tobacco, drug and oil industry lobbyist, and who has been a reliable source for these 'cuckoo science' pieces for years. Curiously enough, both pieces use some of the same sleight-of-hand to fool the unwary (coincidence?).

But never fear, RealClimate is here! (more…)

In 1859, John Tyndall's laboratory experiments showed that water vapour and carbon dioxide absorb infra-red radiation and that they could therefore affect the climate of the Earth. As soon as his paper was published (1861) in the Proceedings of the Royal Society, he put out a press release for the London newspapers explaining that this result implied that all past climate changes were now understood and all future climate changes could be predicted simply from a knowledge of the concentrations of these 'greenhouse' gases…

Fast forward to 2006: Svensmark and colleagues' laboratory experiments show that highly ionizing radiation can create ultra-small aerosol particles. As soon as the paper is published in the Proceedings of the Royal Society, they put out a press release for the world's newspapers explaining that this result implied that all past climate changes were now understood and all future climate changes could be predicted simply from a knowledge of the intensity of these 'cosmic rays'….

History repeating itself? Well, not exactly. Tyndall actually restricted himself to describing his experiments and simply linking it to the work of Fourier a few decades earlier. It took more than another century before the credible quantitative estimates of these effects and their influence on past and possibly future climate were made, along with good enough observations of the gases to know that they have (and continue) to change significantly. However, Svensmark and colleagues, not wanting to wait for the credible quantitative results to come in, instead short circuited all of that tedious follow-up work, scaling up to realistic conditions, theoretical and modelling studies demonstrating that their effect was indeed viable, and simply declared in their press materials that the team had 'discovered that cosmic rays play a big part in the everyday weather' and 'brings to a climax a scientific quest that has lasted two centuries'. Nobel prizes all round then.

Alas! if only it were that simple…. (more…)

In an earlier post, we discussed a review article by Frohlich et al. on solar activity and its relationship with our climate. We thought that paper was quite sound. This September saw a new article in the Geophysical Research Letters with the title «Phenomenological solar signature in 400 years of reconstructed Northern Hemisphere temperature record» by Scafetta & West (henceforth referred to as SW). This article has now been cited by US Senator James Inhofe in a senate hearing that took place on 25 September 2006 . SW find that solar forcing accounts for ~50% of 20C warming, but this conclusion relies on some rather primitive correlations and is sensitive to assumptions (see recent post by Gavin on attribution). We said before that peer review is a necessary but not sufficient condition. So what wrong with it…?

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