June 21st, 2012


Professor of Physics, UC Berkeley


Physicist Richard Muller has challenged the science behind years of climate studies. Through his own analyses, he has now come to agree with many of the conclusions about global warming, but he is not ready to state that humans are the cause. He criticizes scientists who are not open and transparent in publishing their results. 

Richard Muller, professor of physics at the University of California, Berkeley, and founder and scientific director of Berkeley Earth Surface Temperature (BEST), started his career in particle physics, moved into astrophysics, got into cosmology, became fascinated with what killed the dinosaurs, and from there began work on other natural disasters. “I think I have somewhat of a reputation of working on one disaster after another,” he said. 

Muller spent some years researching the cycles of the ice ages, and in presenting his results, he found that audiences were interested mainly in global warming. He turned his research in that direction. When the so-called “Climategate” scandal broke, Muller stated, “I was horrified to learn how these plots had been manipulated and changed with the goal of convincing the public that the conclusions they were drawing should be clear and incontrovertible.” 

In the controversy over climatologist Michael Mann’s “hockey stick” plot, showing 1000 years of temperatures, Muller was a referee for the National Research Council paper. “What was compelling about what he [Mann] had done was that he had argued that the signal went back a thousand years—that was shown invalid by the National Academy study—and that it was evident in a wide range of world data. In fact, what had been discovered was that the hockey stick was derived almost entirely from a few tree ring data sets from North America.” 

When looking at climate studies, Muller stated, “I could not convince myself when I carefully scrutinized the data.” He pointed out the complexities involved in choosing from among the 40,000 measurement stations worldwide and analyzing the data from select stations. He said, “I wanted to know whether global warming was real, and whether it’s caused by humans. 

In conducting his own studies, what are his conclusions? “That the global warming of the past 50 years was very close to what the prior groups had claimed it was. On this issue they were right.” Their failing was not in the work they had done, but in their inability to address openly all of the issues in such a way that an unbiased outside observer would be compelled to accept their conclusions. “There’s a difference of being able to come to a conclusion and being able to convince every skeptic that you come to that conclusion.” One of Muller’s goals is to be more transparent and open in his own work. 

Muller went on to talk about “the deniers” on one side of the climate issue and “the exaggerators” on the other, which is where he places Al Gore. “In the middle, there are the skeptics who’ve done a really wonderful job of pointing out the flaws in the science.” 

How big a risk is global warming to civilization? “Now you’re outside my area of expertise,” Muller said. “Speaking as a concerned human, I think it’s a big risk, a big danger.” If one assumes it is caused by humans, the temperature will keep rising. “The carbon dioxide will go up unless we do something really drastic. And we can’t do this on our own. We have to get China involved. If China continues to add one new gigawatt of coal every week, as they have been doing now for the last decade, whatever we do in the US is irrelevant.” The most important thing we can do, he believes, is to share our expertise in new natural gas technologies with the Chinese. 

Muller also believes that energy efficiency doesn’t get enough attention. “In the future, it is the only thing that is order of magnitude the same size as switching China from coal to natural gas. It could have that big of an impact.”