David Keith on the Australian ABC . . .
http://www.abc.net.au/lateline/content/2012/s3639096.htm
Transcript
TONY JONES, PRESENTER: Earlier today I spoke with geoengineering expert David Keith, Professor of Applied Physics at the Harvard School of Engineering and Applied Sciences. He was in Calgary, Canada.
David Keith, thanks for joining us.
DAVID KEITH, APPLIED PHYSICS AND ENVIRONMENTAL ENGINEERING, HARVARD: Great to be here.
TONY JONES: Now scientists originally calculated that the major impact of global warming would happen towards the end of this century, so geoengineering was considered to be something far off in the distant and really science fiction for most people. Why the urgency now? Why has the debate changed?
DAVID KEITH: I think the debate's changed really because the sort of taboo that we wouldn't talk about it has been broken. So, people have actually known you could do these things for better or for worse for decades, actually since the '60s, but people were sort of afraid to talk about them in polite company for fear that just talking about it would let people off the hook so they wouldn't cut emissions.
TONY JONES: Do you have any sort of idea at all what kind of timescale there might be before governments are forced to seriously consider this? Is it 10, 20, 30, 50 years?
DAVID KEITH: Well, forced is a very fuzzy word, so a popular thing to say in this business is to say that we would do it in the case of a climate emergency. But that's kind of easy to say. In a case of emergency we should do all sorts of wild things, but it's not clear what an emergency is. So I'm a little sticky with the word forced. But I think it could happen any time from a decade from now to many, many decades hence.
The big question right now really is: should we do research in the open atmosphere? Should we go outside of the laboratory and begin to actually tinker with the system and learn more about whether this will work or not. And I'm somebody who advocates that we do do such research.
And one thing that research may show is that this doesn't work as well as we think. And my view is: whether you're somebody who hopes this will work or hopes it doesn't, more knowledge is a good thing.
TONY JONES: So if you were given the go-ahead to do research and the funds to do it, because I imagine it would be very expensive, what would you actually do?
DAVID KEITH: It's not very expensive actually to begin to do little in-situ experiments. So I am working on one and many other people are. So what we would do - the experiment that I'm most involved with would look at a certain aspect of stratospheric chemistry, of the way that the ozone layer is damaged and we'd be looking at whether or not and how much increase of water vapour in the stratosphere, which may happen naturally, and also the increase of sulphate aerosols if we geoengineered might damage the ozone layer.
TONY JONES: Is it clear now or is it becoming clearer that the best strategy if you wanted to go to a global scale would be literally flooding the stratosphere with sulphate particles?
DAVID KEITH: I think the honest answer has to be that we don't know, that you need to do the research in order to have strong opinions about what's the right answer. I would say, you know, if you really put a gun to my head and said, "What's the very most likely thing to work right now?" that's probably it. And the reason is because it mimics what nature has done.
So we have big volcanoes that put sulphur in the stratosphere and we know something about the bad impacts of that and we know something about what it does to cool the planet. And so it seems pretty likely that since we'd be putting in much less than nature puts in, at least for the first half century or more, that we could actually do something and control the risks.
TONY JONES: Yes, is there a fear raised by what you're saying that some country, a superpower, China, for example, has been suggested, could actually do something like this unilaterally and thereby create conflict over the whole idea of geo-engineering?
DAVID KEITH: Yes, it's certainly possible. So, there's no question it's technically possible to do it unilaterally. So, the actual materials you need, the aircraft and engineering you need to do this are something that would be in reach easily of any of the G20 states. It's not hard to do. You could buy the equipment from many aeronautical contractors.
So in that sense it could be done unilaterally. I think that there are scenarios under which it would happen in the real world unilaterally, but I don't think we should - I mean, I think you can exaggerate that possibility.
TONY JONES: And final question, because you probably - if someone decided to do this, even if a group of nations decided to do this, there'd be tremendous scepticism in the public and you would, I imagine, get widespread protests, particularly when people realise that with sulphate particles in the atmosphere you'd actually change the colour of the sky, which has a really big psychological effect on people, you would imagine.
How serious first of all would that change of colour be if you really were able to do it on a global scale and would you expect protests?
DAVID KEITH: I think the change of colour would probably be invisible. I think it wouldn't happen. So people have published papers where they get that, but only where they assume a quite large amount of geoengineering. They assume that geoengineering compensates all of the effect of climate change, which I think is a kind of nonsense policy.