ABC Online Radio National - Counterpoint 11/04/2005 [This is the print version of story http://www.abc.net.au/rn/talks/counterpoint/stories/s1339366.htm]
Climate Change Response
Monday 11 April 2005 Presented by Michael Duffy
Bob Carter, Research Professor of Geology, James Cook University, Townsville, answers your queries arising from our Climate Change show of Monday 4 April.
Michael Duffy: Last week we devoted our entire program to sceptical views of climate change. Our next guest is also a global warming sceptic—Bob Carter is a geologist and environmental scientist, an adjunct research professor at James Cook University, and he specialises in climate change. I’ve asked him on to the program to respond to some of the letters and emails that you, our listeners, sent us after last week’s show. Bob, welcome to Counterpoint.
Bob Carter: Thank you, Michael, it’s a pleasure to be here.
Michael Duffy: A big theme in our listener response was a sense of indignation that we should even be giving time to this viewpoint. Listener Steve Phillips wrote, ‘How is it that a responsible media outlet like the ABC can run a story like this years after the most rigorously peer-reviewed scientific collaboration in history—the Intergovernmental Panel on Climate Change—which concluded categorically that climate change is happening and humans are causing it?’ And we had a lot of other letters on the same lines. Bob, many listeners clearly believe there’s a scientific consensus here. Do you think they’re right?
Bob Carter: Well, coming to the first part of your question, I point out that the people you’ve had on your programs, such as Bill Kininmonth and Aynsley Kellow, are not people whose views you dismiss lightly. Bill used to be director of the National Climate Centre, and Aynsley Kellow’s written a book on the history of the Kyoto Accord and the Intergovernmental Panel on Climate Change’s role in achieving it. Such persons, and myself as you introduced me, are often termed ‘sceptics’ and that’s meant to be a term of denigration, but I’m a scientist…it’s my job to be a sceptic, Michael, and those who are not sceptical towards human-caused global warming or, indeed, towards any other fashionable environmental concern, are acting in unscientific manner…religious, even.
Michael Duffy: So how many people like you are there amongst the ranks of climate experts?Bob Carter: You mentioned the word ‘consensus’, and asked whether there is a consensus on human-caused global warming. It’s an interesting word because it’s a sociological concept, not a scientific one. You don’t, for instance, hear people say that there’s a consensus that the sun will rise tomorrow morning. Rather, clearly understood scientific principles enable us to predict that that will indeed be the case. So when you hear people claim a consensus for some opinion or other…or another example is invoking precautionary principle, either of those statements are of themselves an admission that the science is uncertain and, as Hermann Goering might have said at that point, ‘you should reach for your gun’. Science doesn’t care whether or not there’s a consensus about something. Science only cares whether statements are consistent with known facts and established theories, whether statements are testable and whether they have predictive power. There isn’t yet any general theory of climate, and nor is there likely to be in the near future. So there cannot be a true consensus about predictions for climate change. Is there a social consensus on human caused global warming? Well, yes, on some things. For example, all competent scientists agree that carbon dioxide is a greenhouse gas, but there are huge differences of opinion about the amount of warming that will be caused by increasing the carbon dioxide in the atmosphere; there’s no consensus about that at all. And, in fact, overall the evidence suggests that any warming resulting from that cause will be minor. So if I was to rephrase your question…not say ‘is there a consensus?’ but to ask directly ‘has human-caused global warming been able to be measured yet?’—the answer has to be ‘no’. That’s despite the expenditure of more than $50 billion trying to show that.
Michael Duffy: Perhaps the most common premise that underlies a lot of the emails we’ve received, and also a great deal of what I’ve read about this, is that the climate was pretty stable until the Industrial Revolution. Is that true?
Bob Carter: It’s absolutely untrue. It’s one of the big misconceptions in this whole debate. There’s abundant geological evidence, and it comes especially from cores beneath the ocean sea bed and cores through the ice sheets of Antarctica and Greenland, that in the past climate has varied on a very wide number of scales. Everyone is familiar, for example, with the 11-year sun spot cycle, during which the sun’s radiated output varies just slightly. Then, at the other extreme, there are 100,000 year long cycles in Earth’s orbit around the sun, and that also affects the climate in the sense of driving us into and out of ice ages. In between 11-year and 100,000 year cycles there’s manifold other cycles, some of which we’re only just beginning to discover. Was climate stable before the Industrial Revolution? Well, the Antarctic ice cores tell us that just 20,000 years ago, which is a blink of an eye in geological time, temperature was about seven degrees colder than today in the peak of the last ice age, whereas if we go back before that to the previous warm periods called interglacials, then the three previous interglacials were, respectively, five degrees, four degrees and six degrees warmer than today. So climate has always changed, it always will, and trying to prevent climate change is quite simply futile. Rather, we need to prepare to cope with changes as they occur, be they warmings or coolings.
Michael Duffy: One of our listeners, Eric Storley, is also a great supporter of the IPCC process, as was our last writer, and he said to us, ‘Some of your guests are scientists and should realise you cannot dismiss a peer review discovery without revealing fatal methodological flaws.’ Thanks Eric. But, Bob, let’s talk about perhaps the most famous study underpinning the IPCC view, the so-called ‘hockey stick’. This is a graph that shows the climate as having been stable for about 1,000 years, and then suddenly shooting up roughly 100 years ago. The graph passed two IPCC peer reviews. What do we know now about the ‘hockey stick’?Bob Carter: Well, we know that it’s broken, funnily, that the ‘hockey stick’ was one of three main props that the IPCC used to argue that human-caused global warming was occurring in their last report, which was in 2001. The other two props, incidentally, were the surface temperature measurements made by thermometers that show a rise of temperature of about half a degree since 1970, and the third prop is that computer models predict temperature increases in the future. Now, all three of these arguments are now discredited, including the ‘hockey stick’, which has been shown to be based on flawed statistics. The surface temperature record, we know that that is biased by the urban heat island effect whereby the towns and cities that we live in generate heat locally, and although the curve that you see reproduced in the newspaper or on television is corrected for that curve, there are many, many scientists who believe that the correction is not adequate. At the same time, it conflicts with independent estimates or measurements that we have of changing temperature made in the atmosphere by satellites and weather balloons. They show very little net change over the last 30 or 40 years. And finally, the third argument of the IPCC that the computer models predict warming in the future…well, of course; they’re designed to. They grossly oversimplify and they often just guess at the workings of a climate system that we do not yet fully understand.
Michael Duffy: What do we know about the general global temperatures in the past 50 years, or can’t we say?
Bob Carter: Well, we can say that temperature’s gone up, as measured by the ground base thermometers, about half a degree since 1970, but that we don’t see that same increase when we measure the atmosphere using more sophisticated modern methods. But even if it has gone up half a degree, so what? This is a very small amount of change in the context of the natural changes to the system that I spoke to you about before, and there’s every reason to expect future changes of the same magnitude, anything up to half to a degree to a degree, either up or down, because that’s the way climate is; it’s never stable, it’s always changing.
Michael Duffy: What about the past thousand years, up to about 1900?
Bob Carter: That’s where the big argument is centred over the ‘hockey stick’ because that purports to summarise accurately the temperatures, particularly for the northern hemisphere, over that time period. And the answer is that there is good evidence that in the Medieval warm period and also prior to that in the Roman warm period before the birth of Christ, temperature was at least as warm as it was today, if not indeed a little bit warmer still. Then, in between those warm periods, of course, we’ve had cold periods such as the famous Little Ice Age experienced in Europe in the 17th, 18th centuries.
Michael Duffy: Another one of our listeners, Richard Evans, wrote, ‘The one fact that does not seem to be in dispute is the progressive rise in the concentration of carbon dioxide in the atmosphere.’ Bob, is this right and, if it is, is the IPCC right in saying that more carbon dioxide will automatically produce warmer temperatures?
Bob Carter: Well, Michael, the short answers to that are yes, and yes, and isn’t that great, basically. As I mentioned earlier, all scientists agree that carbon dioxide is a greenhouse gas. That is to say, it has a warming effect. That said, the balance of the evidence also suggests that the amount of warming that will be produced by the famous doubling of carbon dioxide that is always spoken about, that warming will amount to only a few tenths of a degree. Now, that’s at the level of the noise in the climate system, so it’s not something that one should be overly concerned about. Two other points about carbon dioxide; the first is that we have a record of carbon dioxide from the ice cores which preserve as little bubbles samples of the atmosphere in past times. An analysis of those cores shows quite clearly that, in the past, rises in temperature, when they occurred, occurred before the rises in carbon dioxide, and the period is between a few hundred and a few thousand years. Now, if temperature rises before carbon dioxide, then it cannot be the primary cause of that temperature change. I mean, you don’t hear people saying that lung cancer causes smoking, now do you? A second point about carbon dioxide is that increasing it in the atmosphere is actually a benefit to human kind. Why? Well, first because it’s a very powerful aerial fertiliser which increases plant productivity, and it’s one of the reasons the increases in level…why we’ve had a green revolution, and it helps us feed the world. The second is that mild warming, of the sort that’s likely to be produced by an increase in carbon dioxide, is actually a very useful insurance policy because if there’s one thing that all climate scientists agree on, it’s that we’re going to go into another ice age. Now, we don’t know exactly when but, nonetheless, a little bit of warming will go a long way and is not by any means the bad thing that it’s made out to be every day.
Michael Duffy: If your view of this is right and global warming is a horror story that’s not supported by the known facts, then I guess four groups of people who’ve convinced most of us to take it seriously have acted somewhat strangely. I’m thinking of the IPCC, the environmental movement—or some of it, the media, and of course governments. Would you mind just running through those four groups briefly and telling us why you think that each of them are so attracted to this idea?
Bob Carter: Well, I don’t think that they’ve acted strangely. I think they’ve acted more as less exactly as you would expect them to. For example, take the environmentalists; as political groupings they wish to attain political ends, and they therefore use and acknowledge science only when the results of science suit those political ends. When the science results are ambiguous or don’t suit (this is the case for human-caused global warming) the environmentalists invoke the precautionary principle, I guess, and very often resort to personal attacks on people who point out the obvious, which is that we have not yet been able to measure human-caused global warming. The second you mentioned, the IPCC; it’s received advice from many excellent scientists and they’re still involved with the IPCC, but it’s not primarily a scientific body. In the end, it’s a political body with a life of its own and, as such, the advice to policy makers that the IPCC releases no longer gives primacy to scientific reasoning. It actually gives primacy to political advice. Thirdly, and probably the biggest problem of the lot is governments and the bureaucrats who advise them. Why is that? It’s because they’ve decided that research funding should be directed towards activities that they or the tax payer perceive to be ‘useful’. Now, as soon as you do that, it’s quite inevitable that scientists’ efforts become slanted towards problems that they think are of public concern. After all, in essence; no climate change problem, then no climate change research money. And this is much more damaging than just at the level of the individual scientist. For example, as a result of this policy, organisations such as CSIRO now resemble government consultancies rather than genuine science research agencies. In effect, the government no longer does, or even can, receive disinterested advice on science issues of today. And the fourth group, I guess, is the media, and because the media is kindly using me today I have to be careful what I say I guess…
Michael Duffy: No, please, say whatever you like.
Bob Carter: …but the media’s job, surely, is entertainment and making money, and both of these are enhanced by a good scare story, which scientists now produce in abundance. You may think I’m making this up but the latest that I’ve heard are, firstly, that dandruff enhances global warming, and the second one is that an amino acid which is produced by blue-green algae when they bloom in the Baltic Sea in the northern hemisphere, that chemical is known to cause Alzheimer’s disease, and so there’s a claim that Alzheimer’s disease in Nordic countries is going to increase as a result of global warming. It’s not difficult to produce these scare stories and, to be fair, the media finds them very useful to help them sell newspapers.
Michael Duffy: Thanks very much for coming on the program, Bob. We’ll leave it there.
Presenter: Michael Duffy