An Interview with Nigel Calder On Climate Change

By | July 19, 2007

An Interview with Nigel Calder[i]

Nigel Calder, former editor of The New Scientist and author of innumerable books and articles on science, including The Chilling Stars[ii], in conversation with Pan Pantziarka.

LBR: Do you think that there has been a change in the debate on climate change recently? Is there a greater willingness to entertain alternative views on the causes of climate change?

NC: A local victory for free speech has occurred in the BBC, where an internal report on impartiality (June 2007) picked out climate change as a subject where dissenting voices really should be heard. That verdict is already having some effect, although BBC reporters still tend to assume that the Intergovernmental Panel on Climate Change must be right. More generally there's a contrast between a hardening of attitudes on the part of the scientists, politicians and journalists in the 'man-made global warming' camp, which contrasts with more open scepticism among the general public. One reason for the latter may be horror fatigue, about all the scare stories. Another is a suspicion that politicians are glad of a new excuse to raise taxes. But most importantly there is plain common sense about the weather's variability. If you're told that a warm UK April 2007 is foretaste of hotter times to come, you cannot but ask what a cold and wet June portends. And while some of the media and greenhouse scientists have fiercely attacked The Chilling Stars and Henrik Svensmark's theory, I've not heard a single complaint from friends, or friends of friends. It was the same when I appeared in the Channel 4 documentary 'The Great Global Warming Swindle'.

LBR: Given the controversy over 'The Great Global Warming Swindle?, do you think your decision to take part was a wise one?

NC: Yes. I was in distinguished company with a string of prominent scientists to demonstrate that critics of the man-made warming hypothesis are not just a bunch of crackpots. There's been almost no attempt to rebut what we interviewees said individually and criticisms were focused on some linking narrations and explanatory animations, which some of us might have scripted a bit differently. By the way, Al Gore's movie 'An Inconvenient Truth' is applauded by greenhouse scientists even though they know know it contains misleading statements. To be inaccurate in a politically correct cause seems to be OK in their ethos.

LBR: Do you think that the idea of a scientific 'consensus' on climate change is now so firmly entrenched that it can't be shifted?

NC: The idea of a settled consensus is alien to productive science. In any branch of research that isn't moribund, battles rage between the entrenched bigwigs and their cronies, versus others who challenge their hypotheses. What makes science so valuable for our species is that eventually errors are corrected and ideas shift. But that can be a slow and painful process taking 10-20 years. In the case of climate science, control of public research funding by the 'consensus' makes life difficult for the likes of Henrik Svensmark. Mother Nature may speed the change of heart if, as some of us half-expect, the next few years bring evidence of global cooling. Did you hear that on 9 July Buenos Aires had its first significant snowfall since 1918?

LBR: What kind of empirical evidence do you think would be needed to prove the theory that anthropogenic CO2 emissions cause global warming?

NC: It's likely that CO2 has some warming effect, but real proof of that hypothesis is tricky. You have to confirm by observation exactly how the CO2 changes the situation at different altitudes in the atmosphere and in different regions of the world. For example, CO2 is supposed to warm the upper air faster than the surface, but the measurements don't show that happening. When the CO2 effect is eventually pinned dow, it will probably turn out to be weaker and much less worrisome than predicted by the global warming theorists.

LBR: How do you respond to the paper by Lockwood and Froehlich, which claims to comprehensively 'settle the debate' on the cosmic ray hypothesis you describe in The Chilling Stars?

NC: How often we've heard it before, that the debate has been settled! But this is an interesting case because these scientists accept that the Sun has played a big part in climate change over hundreds and thousands of years, just as we explain in the book. They even allow that it was involved in the warming in much of the 20th Century. And when Lockwood and Froehlich go on to say that the intensification of solar activity seen in the past hundred years has now ended, we don't disagree with that. We part company only when they say that temperatures have gone on shooting up, so that the recent rise can't have anything to do with the Sun, or with cosmic rays modulated by the Sun. In reality global temperatures have stopped rising. Data for both the surface and the lower air show no warming since 1999. That makes no sense by the hypothesis of global warming driven mainly by CO2, because the amount of CO2 in the air has gone on increasing. But the fact that the Sun is beginning to neglect its climatic duty — of batting away the cosmic rays that come from 'the chilling stars' — fits beautifully with this apparent end of global warming.

LBR: How can non-scientists make any sense of the competing theories being proposed, when even the observational evidence is being disputed?

NC: Forget the politics, if you can, and remember that, at the cutting edge of discovery, scientists are no more certain about what's really going on than men or women in the street. When a new finding is really surprising it falls outside the scope of existing curricula. There are neither textbooks nor highly trained people around, to be aloof in their specialist expertise. In such cases the discoverers sometimes short-circuit the academic process and take their discoveries to the general public as quickly and as directly as possible. Galileo, Darwin and Einstein all did that. They flattered their readers' intelligence as well as enlightening them, and let them make up their own minds about whether to believe the new stories. It's in that long tradition that Henrik Svensmark and I present in plain language Henrik's astonishing realization that our everyday clouds take their orders from the Sun and the stars. We're entirely happy that our readers, whether scientists or non-scientists, should weigh the arguments and form their own opinions, for or against us.

[i] Original here:

[ii]  Keywords: Climate change, global warming, science, science policy

Title: The Chilling Stars

Author: Henrik Svensmark and Nigel Calder

Publisher: Icon Books/Totem Books

ISBN: 1840468157

Despite the claims of some politicians and scientists, the science of climate change is far from settled. While the mainstream seems to have accepted that global warming is real and that it is caused mainly by man-made carbon dioxide (CO2) emissions, there are many scientists who dispute what is still a speculative theory that depends heavily on mathematical models rather than solid theoretical understanding and empirical evidence. However, the political climate is such that discussion of these issues is difficult, and those who dispute the official position (as exemplified by the IPCC Summary Reports) are likely to be attacked as 'climate change deniers' (note the deliberate allusion to 'holocaust deniers').

For those who accept that global warming is taking place, there are a number of alternative theories as to the causes. One of the leading alternative theories is that proposed by Danish physicists Henrik Svensmark and Eigil Friis-Christensen, which suggests that it is variations in cloud cover that have a large effect on climate, and that clouds are seeded by cosmic rays, which are in turn influenced by the Sun's magnetic field.

In 'The Chilling Stars', science writer Nigel Calder and Henrik Svensmark present the first popular exposition of the theory. In doing so they present not just the bare bones of the theory, but also show how it can explain both past climate events and the present situation. In particular the authors make sure that a whole range of supporting evidence is used to establish historical climate trends (including events such as the Medieval Warm Period and the Little Ice Age) and to tie this in with records of solar activity.

As well as presenting the correlation between the historical climate record and solar activity, there is also an explanation of the physical process by which cosmic rays kick-start cloud formation. The theory is explained clearly, along with details of the experimental evidence used to support it. There is also a clear explanation of how the electromagnetic activity of the sun controls the rate at which cosmic rays reach the earth.

While it's Svensmark's theory that is at the heart of the book, much of the supporting evidence comes from other researchers and scientists. The work of Nir Shaviv, Jan Veizer and others is also mentioned in some detail, illustrating both the cross-disciplinary nature of the theory – which takes in cosmology, particle physics, paleoclimatology and meteorology – and the fact that there is a degree of support for the theory from a range of academics working in different countries and different fields.

Given the controversial nature of the subject, it would have been easy to write this book as a piece of scientific polemic. But on the whole, the emphasis is more on the merits of the theory – which Svensmark calls cosmoclimatology – than on politics and polemics. In some respects more could have been made of this, but it's clear that the authors were more intent on making a case for the theory rather than in explicitly attacking the 'consensus' view.

For those who believe that the argument about the causes of climate change have been settled may find this a difficult book to read. But those who retain an open mind may find this an interesting read, even if it is only to confirm that the science is far from being settled.


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