We’re sure some of you will be interested in reading a transcript of the interview we did with Professor Richard Muller on Wednesday. BEST published their new results at the start of the week, accompanied by an op-ed in the New York Times from Professor Richard Muller, the founder of the project, and effectively the figurehead.
The interview went on for about half an hour, and there was too much to put into our (already quite long) write up, which is here. The interview was done over Skype, and there are a few places where the sound cuts out or words were hard to hear. Feel free to repost – please include a link to this post and a credit to Carbon Brief.
Our questions are in italics.
Interview with Richard Muller
What was it about previous temperature data work that moved you to start the BEST project?
(First few seconds of recording are missing. Muller says: Three years ago I felt major issues were raised about previous studies. I was not convinced they came to scientifically solid conclusions.)
They had used only a fraction of the data. We did a study in which we used essentially all of the data.
There were issues about station quality – Anthony Watts had shown that many of the stations had poor quality. We had studied that in great detail. Fortunately, we discovered that station quality did not affect the results. Even poor stations reflect temperature changes accurately.
There were issues of data changes. Some of the prior groups had adjusted the data and lost all record of how they had adjusted it. So we went back to the raw data and used only that – and that was important.
Two more things. The urban heat island effect. That was something we studied I think in a clever and original way. [As opposed to] using all the stations, we could derive the temperature rise based only on rural stations. We got the same answer.
Finally, the existing conclusions were based on extremely complex global climate models. And these, you could never track down how many adjustable parameters they had, you could never track down how many hidden assumptions there were. In our approach, we used a very simple approach.
We’ve been criticised for being simple but there’s a principle in science called Occam’s razor , it says that things that can be derived simply are much more likely to reflect the truth than things that are hidden under huge complexity. We had very few adjustments to make and we find a really good match between the carbon dioxide and the temperature rise, and a very poor match between solar variability and temperature rise. So based on that we reached our conclusions.
I suppose those were the five key things that concerned me back then and it took us two and a half years of very hard effort to address all of them. Most of the work, I have to say, was done by a young scientist called Robert Rohde. I just give him enormous credit for having come up with the best [BEST?] statistical approach – which, we believe, is the one that leads to the smallest uncertainties in determining the record, and that was absolutely key for us to reach our conclusions.
I’m just picking you up on the charge of being oversimplistic…
They have it backwards. There are people who say that, for example, some people say you need something that has 30 parameters in it, and then we can make it fit and conclude that’s right. Well, 30 parameters – you can fit anything.
When you can make it fit with virtually no adjustable parameters, in that simplicity lies the truth. There’s been a lot of knee-jerk reaction to this because we’ve done something in what I consider a more elegant way. I’ve been in physics a long time. I’ve made major discoveries. I’ve worked on everything from particle physics to astrophysics. I’ve worked on two projects that won Nobel prizes for the people I hired to continue them. And in all these cases, it was the simple analysis that led to the great discoveries. When things are true, Feynmann said, the wonderful thing is there’s a simple way to understand it. So the simplicity is not a weakness. I think many people – many of whom I notice have never discovered anything in their life – believe that in complexity lies the truth. But the glory of physics is that things, sometimes hit you in the face. And that’s the case here.
One of the people who’d suggested the study was too simplistic was Judith Curry, who’d declined to be a co-author on the paper. Do you feel like the study lacked a climatologist? Do you wish there had been one on the team?
Am I not a climatologist?
Well, you’re a particle physicist…
How about the papers that I’ve written on climatology that were published in Science, in Nature, in the Journal of Geophysical Research? How about a technical book I wrote on the history of climate? That doesn’t count? I am more famous for other things I’ve done, but I’ve spent 10 years in climatology. I think my credentials are as good as anyone else’s in that field.
No, Judith Curry told us she didn’t want to be in the paper because she felt she hadn’t contributed to it. And then she also disagreed with our findings, I think in part because her approach – she has an alternative theory. Her alternative theory is that climate is random. And I’ve said to her that the unfortunate aspect of her theory is that it’s untestable. Now a theory that’s untestable is not something I consider to be a theory. She can take the point of view that it’s an accident – that the climate just happened to match the carbon dioxide.
I mean there are many things it doesn’t match: we tried many things, we tried an exponential increase, we tried a population increase and it didn’t match any of those. Her response is: “Your match is accidental”. Her theory is no matter what you see, she can match it with a random variation. That’s an untestable theory. We say in physics it’s undeniable – you cannot prove it wrong. That’s not really, in my mind, a valid alternative.
If she came up with something that’s testable I would love to test my hypothesis against hers. But she doesn’t have one.
You were, in a sense, responding to skeptic critiques of surface temperature data…
I was listening to the skeptics, and appreciating that what they were saying had validity.
Do you think ocean warming has been obscured in this argument?
There were many things that have not been included, we didn’t include the ocean, we didn’t include the upper atmosphere, we didn’t include the middle atmosphere. All of these studies…
(Muller takes a phone call.)
What we chose to study is the part of the temperature that is most critical to humans – the land surface. That’s also more sensitive to greenhouse gases than are the oceans, because the oceans absorb a lot of heat. So we began our study by picking the most critical part and the part that should have the biggest effect, which I think was a wise choice.
Some people study the oceans, too. Other people adopt the ocean models of other people when they include it in. Some people include the upper atmosphere and don’t – some people do the oceans, don’t do the upper atmosphere. You have to pick what you’re going to do. You can’t do everything. We don’t have good data on the middle atmosphere, which is obviously important, but we felt that the land data was the optimum thing to choose for this kind of study.
After you came out with the data you were making broader statements about the globe warming when you were looking at part of the data, which is obviously extremely important, but…
No-one can look at all the data though. (Bad skype line for a few seconds.) When people say global warming they’re not including the middle atmosphere. (Bad line.) …which comes from around the world. If we included the oceans, which we can do by simply taking the ocean results of others. This is something that other groups have done – Jim Hansen at NASA, for example, takes the ocean data from NOAA – we can include that in, it doesn’t add information or change any conclusions. It doesn’t’ go back as far as the land record goes and so that’s unfortunate. We don’t have ocean measurements that go back to the 1750s because nobody did them back then. So the land data is really the best choice for the kind of issues that are of importance to the world.
I was wondering… your Op-ed in the New York times, and previous media coverage, talks about you being a ‘sceptic’ who converted. And yet in your book, Physics for Future Presidents, even though you’re counselling against overstating the findings of climate science, you don’t question the fundamentals of climate science, or indeed that humans are contributing to the greenhouse effect…
I’m glad you noticed that. I have considered myself only to be a properly sceptical scientist. Some people have called me a denier – no, that’s completely wrong. If anything, I was agnostic.
But I also just don’t hear you protesting very much against the media storyline that seems to have emerged that you were somehow a ‘sceptic’ beforehand, a sceptic in the way that…
Come on, you know you can’t really counter the media. That would be a full-time job if I were to simply try to respond to everything, you know, write letters to the editor… I just hope that some people like you will read my books and read my papers, and read what I say – and not what people say I say.
My new book, my Energy for Future Presidents book, I think, lays it out also again. That still 90 per cent of what’s said about climate change is nonsense. That when people attribute Hurricane Katrina, or dying Polar bears, to climate change, that’s not based on any science whatsoever. In fact in many cases, it’s wrong. The number of hurricanes has not been going up, it’s been going down slightly. The number of tornadoes has not been going up, it’s been going down slightly. 90 per cent of the information given in the movie Vice President Al Gore’s movie An Inconvenient Truth is misleading, exaggerated or just plain wrong. So there’s plenty of room for skepticism. What we have addressed is the critical issue of temperature change, and we’ve come up with answers that illustrate I think what happens when science is done in a straightforward and transparent way.
We reached conclusions that three years ago I would not have guessed that we’d reach.
You mentioned in an interview before you released the first study that you were hoping to bring some peace to the climate debate…
I’m still hoping.
…Has the BEST work so far been received so far in the way that you’d hoped?
Yes, I mean, I don’t expect, of course, the media, forgive me for that phrase, but the media contacts everyone and says what’s your reaction to these five papers that you haven’t read based on the op-ed. And of course they have a quick reaction, well I don’t think… it’s too simplistic.
I don’t think anybody who has responded in the media so far has actually studied our work. We don’t expect immediate agreement on such things. What we expect is that by being transparent, open and clear – by having the data online and the computer programmes so people can see precisely what we did, that – over the coming weeks and maybe months – that gradually the debate will be cooled and people will recognise what it is we really did. And that we will forge a scientific consensus – that we will help with that.
I think that many of the skeptics are, indeed, open-minded. But until they really look at what we did they properly should remain skeptics, and not be convinced by an op-ed piece. They’re not going to say: “Oh, if Muller changed his mind, then I will too.” That’s not the way scientists work and it’s not the way any intelligent humans work.
More specifically, I notice you’ve been in touch with Anthony Watts a fair amount and listened to his concerns. Had you expected him to be more accepting of the results so far? Do you think that his recent paper is a response to your work?
Oh no, he didn’t even know about our work. His paper has nothing to do with our announcement. His new paper was written over the past few months, and it was written based on our analysis of the temperature quality, or the station quality. In fact our station quality paper doesn’t disagree with his previous paper. Now he’s putting a new spin on it, saying that if I make up a new version of station quality, I can show that with this new version there is a difference between the uncorrected stations and the corrected ones.
That’s great. I don’t know whether that reflects his method of choosing the stations or whether it’s truly an unbiased approach. We don’t know yet because he hasn’t released the stations – we don’t know how he did it. Well, we do know how he did it – he listed his criterion, but we don’t know how he came up with those criterion. We have to study his results, but that has no bearing on our just-released results. He didn’t know about them. Our papers were not released until the same day or right after he released his new paper. He hadn’t seen those results – he’s not really addressing our results.
Had you hoped he’d be more accepting of your original… of the work that you released last year?
Well, look, our work on station quality agreed with what he published. Now he’s saying: “If I use a different criterion I find that the uncorrected data can yield a bias”. Well, that sounds reasonable – if a station moves and you don’t take that into account, yeah, you’re likely to get a bias. I don’t see any really strong objection to that. And so what he has done was interesting and it continues to be interesting, but it doesn’t affect our new conclusions.
Do you feel the Urban Heat Island effect still poses problems for estimating global temperatures, or do you think you have settled that issue?
Oh, I think that has been settled. There are some people who continue to raise objections – but the trouble with referee comments is that they’re not refereed themselves, and there have been some very silly things said by referees. I think that the urban heat island has been addressed by the three major groups, and now it’s been addressed by us. The fact is urban heating is seen, but the fraction of the globe that’s urban is so small that it’s very hard to imagine that there would be a major urban heat island effect contribution.
I noticed on Wattsupwith that Ross McKitrick asked for major reviews to be made to the original BEST study?
Yes, we got Ross’s reviews, and the ones that were really valuable were that he gave us references that we needed, and so on. But in fact we wrote back to him for many of the things he said were mistaken and based on a misinterpretation of what we had done. So we wrote back to him and gave him our comments on his reviews and why we thought that many of them were wrong. This is what’s called the peer review process, where we engage in this.
I was wondering how that tallies with Elizabeth Muller (Professor Muller’s daughter and BEST co-founder)’s assertion that none of the paper’s reviewers pointed out mistakes?
There were no mistakes in that paper. McKitrick had comments and things he thought were mistakes, but we wrote back to him and told him why he was wrong. I’m surprised that he still thinks they were mistakes. We did write back to him and he did have useful things to say. But there was really no change of substance. And I think the conclusion that urban heat islands contribute essentially zero to the warming we see is on very solid ground. He may nitpick over some little things, but nothing important.
You were talking about how three years ago things that you had seen cast doubt on your confidence in some of the warming data. I was wondering how of that was due to Climategate and how you view the episode now. Has your view of what happened – and the way that the scientists involved behaved – evolved?
I think Climategate was inexcusable. I think what they did amounts to scientific misconduct – malpractice, if you will. Scientists, we have to be completely open with our data. We try to do that – we may not be perfect, but we certainly try to put our data online, to give everybody everything.
The UK group purposefully hid the discordant data, and they did it in order to make sure that people drew the same conclusions that they drew, and to me, that’s misconduct. If they had science licences, the licences would be taken away. The people who engaged in that had very bad behaviour, unbecoming of a scientist and I believe they really deserve to be ashamed for that.
They were exonerated, they did nothing illegal. But there’s a lot more beyond what’s legal. When you hide data from other scientists. And it wasn’t using tricks – that was bad – it was hiding the data that I thought was malpractice.
Are you talking about them hiding data from, for example, Steve McKintyre?
From everybody! They mentioned that they had taken away data but they wouldn’t release it. And Steve McKintyre, I think rightly, observed that this should is something that scientists should be allowed to see. And from their emails we learned that the reason they hid it was they were afraid other people would draw a different conclusion from what they had.
So it was really very bad behaviour. By the way, most people in this business believe those emails were not hacked. They were leaked.
I wanted to ask about your future plans for BEST. Could you envisage broadening the range to areas such as attribution studies?
There are a lot of things. We do want to add in the oceans. We have this enormous database, which is worth exploring. We’re deeply interested in the role of ocean currents – we have one paper that has been accepted and it’s just waiting for publication – and how they affect decadal and subdecadal variation, the El Ninos and the Atlantic Gulf Stream. We’re looking at that, and there’s some effects that come from those.
We’re thinking about starting a new section of our study to look at policy, and what can be done about it. So the Berkeley Earth may actually have a separate section now that looks deeply again, in what I like to think is an objective scientific manner, on what could be done. That’s something that Elizabeth [Muller] is particularly interested in. She has a background in that kind of policy issue. So lots of things to do – way too much to do. If you know anyone who wants to give us some money to support this, please put them in contact.
How do you see your position in all of this in the future? Do you want to be the spokesman for BEST on future projects? How do you see your role?
I think I’ve been chosen by the media as the spokesman – you’re welcome to call everybody else on the team. They tend to call me because I was asked to testify before Congress and so on. Elizabeth and I created this project – she had an op-ed in the San Francisco Chronicle on Monday – yesterday – too. I have no care about… Our goal is to focus and concentrate on the science, to do it in an objective way, and hope that by doing this we will set an example for future work in this field. An example not only in being objective, but also in being open and transparent, and putting all the work online in such a way that people will be able to duplicate it and if, in fact, they feel we made a mistake, they can point to what it is.
Some people will say the result is too simplistic. That’s a valid argument from a scientist. My whole experience in science is just the opposite – that discoveries that are made through a simple argument are the ones that turn out to be right in the long run and are the ones that are actually most compelling – they’re the hardest ones to prove wrong. But some scientists disagree. They say no, no – the only thing that really works is if you have large, complex computer programmes. I disagree with that. But that’s a valid scientific objection. In the end it’s our objectivity and transparency that allows such criticisms to be made. We tell everybody what we did and how we did it, and I think that’s the scientific process. What we’re really hoping for is to return this type of transparent science, to strengthen it, in climate science. Let the politicians argue over what can be done about it. I think that science is that small realm of knowledge in which universal agreement can be achieved. Let’s do that with climate science, and then lets leave to the politics and the diplomacy what can be done about it.
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