tagged w/ richard muller
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By Richard A. Muller
Published: July 28, 2012
CALL me a converted skeptic. Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: Humans are almost entirely the cause.
My total turnaround, in such a short time, is the result of careful and objective analysis by the Berkeley Earth Surface Temperature project, which I founded with my daughter Elizabeth. Our results show that the average temperature of the earth’s land has risen by two and a half degrees Fahrenheit over the past 250 years, including an increase of one and a half degrees over the most recent 50 years. Moreover, it appears likely that essentially all of this increase results from the human emission of greenhouse gases.
These findings are stronger than those of the Intergovernmental Panel on Climate Change, the United Nations group that defines the scientific and diplomatic consensus on global warming. In its 2007 report, the I.P.C.C. concluded only that most of the warming of the prior 50 years could be attributed to humans. It was possible, according to the I.P.C.C. consensus statement, that the warming before 1956 could be because of changes in solar activity, and that even a substantial part of the more recent warming could be natural.
Our Berkeley Earth approach used sophisticated statistical methods developed largely by our lead scientist, Robert Rohde, which allowed us to determine earth land temperature much further back in time. We carefully studied issues raised by skeptics: biases from urban heating (we duplicated our results using rural data alone), from data selection (prior groups selected fewer than 20 percent of the available temperature stations; we used virtually 100 percent), from poor station quality (we separately analyzed good stations and poor ones) and from human intervention and data adjustment (our work is completely automated and hands-off). In our papers we demonstrate that none of these potentially troublesome effects unduly biased our conclusions.
The historic temperature pattern we observed has abrupt dips that match the emissions of known explosive volcanic eruptions; the particulates from such events reflect sunlight, make for beautiful sunsets and cool the earth’s surface for a few years. There are small, rapid variations attributable to El Niño and other ocean currents such as the Gulf Stream; because of such oscillations, the “flattening” of the recent temperature rise that some people claim is not, in our view, statistically significant. What has caused the gradual but systematic rise of two and a half degrees? We tried fitting the shape to simple math functions (exponentials, polynomials), to solar activity and even to rising functions like world population. By far the best match was to the record of atmospheric carbon dioxide, measured from atmospheric samples and air trapped in polar ice.
Just as important, our record is long enough that we could search for the fingerprint of solar variability, based on the historical record of sunspots. That fingerprint is absent. Although the I.P.C.C. allowed for the possibility that variations in sunlight could have ended the “Little Ice Age,” a period of cooling from the 14th century to about 1850, our data argues strongly that the temperature rise of the past 250 years cannot be attributed to solar changes. This conclusion is, in retrospect, not too surprising; we’ve learned from satellite measurements that solar activity changes the brightness of the sun very little.
How definite is the attribution to humans? The carbon dioxide curve gives a better match than anything else we’ve tried. Its magnitude is consistent with the calculated greenhouse effect — extra warming from trapped heat radiation. These facts don’t prove causality and they shouldn’t end skepticism, but they raise the bar: to be considered seriously, an alternative explanation must match the data at least as well as carbon dioxide does.
Adding methane, a second greenhouse gas, to our analysis doesn’t change the results. Moreover, our analysis does not depend on large, complex global climate models, the huge computer programs that are notorious for their hidden assumptions and adjustable parameters. Our result is based simply on the close agreement between the shape of the observed temperature rise and the known greenhouse gas increase.
It’s a scientist’s duty to be properly skeptical. I still find that much, if not most, of what is attributed to climate change is speculative, exaggerated or just plain wrong. I’ve analyzed some of the most alarmist claims, and my skepticism about them hasn’t changed.
Hurricane Katrina cannot be attributed to global warming. The number of hurricanes hitting the United States has been going down, not up; likewise for intense tornadoes. Polar bears aren’t dying from receding ice, and the Himalayan glaciers aren’t going to melt by 2035. And it’s possible that we are currently no warmer than we were a thousand years ago, during the “Medieval Warm Period” or “Medieval Optimum,” an interval of warm conditions known from historical records and indirect evidence like tree rings. And the recent warm spell in the United States happens to be more than offset by cooling elsewhere in the world, so its link to “global” warming is weaker than tenuous.
The careful analysis by our team is laid out in five scientific papers now online at BerkeleyEarth.org. That site also shows our chart of temperature from 1753 to the present, with its clear fingerprint of volcanoes and carbon dioxide, but containing no component that matches solar activity. Four of our papers have undergone extensive scrutiny by the scientific community, and the newest, a paper with the analysis of the human component, is now posted, along with the data and computer programs used. Such transparency is the heart of the scientific method; if you find our conclusions implausible, tell us of any errors of data or analysis.
What about the future? As carbon dioxide emissions increase, the temperature should continue to rise. I expect the rate of warming to proceed at a steady pace, about one and a half degrees over land in the next 50 years, less if the oceans are included. But if China continues its rapid economic growth (it has averaged 10 percent per year over the last 20 years) and its vast use of coal (it typically adds one new gigawatt per month), then that same warming could take place in less than 20 years.
Science is that narrow realm of knowledge that, in principle, is universally accepted. I embarked on this analysis to answer questions that, to my mind, had not been answered. I hope that the Berkeley Earth analysis will help settle the scientific debate regarding global warming and its human causes. Then comes the difficult part: agreeing across the political and diplomatic spectrum about what can and should be done.
Richard A. Muller, a professor of physics at the University of California, Berkeley, and a former MacArthur Foundation fellow, is the author, most recently, of “Energy for Future Presidents: The Science Behind the Headlines.”By Richard A. Muller
Published: July 28, 2012
CALL me a converted skeptic. Three... more
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Watch the live webcast of this hearing at link
Dr. Richard Muller, Author of Berkeley Temperature Study, Makes First Appearance on Hill After Releasing Results; Drs. Ben Santer, William Chameides to Present Latest Research on Global Warming
WASHINGTON - Three prominent scientists will present the best case yet for the end of climate skepticism in Washington and the world over the fact that the world is warming at a congressional briefing held by Rep. Ed Markey (D-Mass.) and Henry A. Waxman (D-Calif.).
The briefing will feature the first appearance on Capitol Hill by Dr. Richard Muller since the release of the Berkeley Earth Surface Temperature project results. Dr. Muller was previously skeptical about many aspects of climate science, but the massive two-year study he led has validated the fact that the world is warming. His work also debunked many talking points repeated by climate science deniers that have been repeated by lawmakers on Capitol Hill.
Dr. Ben Santer of the Lawrence Livermore National Laboratory will discuss new research on recent warming. Dr. William Chameides, dean of Duke University's Nicholas School of the Environment and vice-chair of the National Academies' Committee on America's Climate Choices, will discuss the findings of the National Academies' America's Climate Choices reports.
WHAT: Congressional climate science briefing: "Undeniable Data: The Latest Research on Global Temperature and Climate Science"
WHERE: 1324 Longworth House Office Building, Washington, D.C.
WHEN: Monday, November 14, 2011, 2 PM
WHO:
Dr. Richard Muller
Director of the Berkeley Earth Surface Temperature Project
Dr. Ben Santer
Research Scientist at Lawrence Livermore National Laboratory
Dr. William Chameides
Dean of Duke University's Nicholas School of the Environment
Vice Chair of the National Academies' Committee on America's Climate Choices
http://democrats.naturalresources.house.gov/hearings@id=0108.htmlWatch the live webcast of this hearing at link
Dr. Richard Muller, Author of... more
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by Chris Mooney
I’ve been watching with interest the blogosphere uproar over the release of results from the Berkeley Earth Surface Temperature project centered around physicist Richard Muller [pictured left], which now claims to confirm that the world is indeed warming.
As Joe Romm notes, this is mainly newsworthy not for the finding itself—we’ve known this to be true for ages—but because Muller had talked as though he was coming from the other side, the skeptical side, and had received Koch funding. And as Romm notes, the uber-skeptic blogger Anthony Watts had said of Muller’s undertaking, “I’m prepared to accept whatever result they produce, even if it proves my premise wrong.”
Now, however, Watts is blasting the Muller group for releasing results short of peer review, and calling for an open peer review process and “transparency” so no “pals” handle the papers.
In other words, it appears to me as though Watts is building a series of arguments and complaints that will allow him to *not* “accept whatever results they produce, even if it prove my premise wrong.”
This is a classic phenomenon called goalpost shifting. And we have seen it many, many times before, on many, many disparate issues.
Goalpost shifting is what the hard core birthers did when President Obama released his long form birth certificate. It’s what Harold Camping did when the “rapture” didn’t materialize on May 21. It’s what the famous (or infamous) Seekers did when the world didn’t end on the day they predicted in 1954…an event that fed directly into the development of cognitive dissonance theory.
The way the human mind works is that people who are strongly committed to a preexisting point of view that is central to their identities—and especially people who have built up elaborate arguments and rationalizations of that prior point of view—will be unable to let it go, often even in the face of direct factual refutation. This amply describes many climate skeptics and deniers, who claim their views are based on science, but clearly take politicized positions, and attack climate scientists as though they’re berating members of an outgroup.
The emotional tone itself reveals that these attacks on science are motivated attacks—they occur for a reason, because they serve a purpose. And that purpose is rooted in the identities and beliefs of climate skeptics, who have, shall we say, a need to disbelieve.
So whatever “data” come out, hard core “skeptics” are unlikely to change; although more moderate skeptics (and it seems Muller may have been one of these) may prove much more flexible.
What this means is that it is really silly for journalists to be covering the Muller team work in some sort of naïve “will-this-change-the-debate” sort of way. It won’t change the debate. It is just fuel for the fire. No scientific result, of any kind, is going to “end” the global warming debate in the public arena (it ended long ago in the scientific arena).
Muller himself lends credence to this naivete in his Wall Street Journal oped: "Global warming is real. Perhaps our results will help cool this portion of the climate debate."
Yeah, right. You want to cool the global warming debate? There is only one way to do it. It is called find a policy solution to the climate issue. At that point, the scientific debate becomes irrelevant.
The hard core “skeptics” still won’t buy it, of course. But they will have ceased to matter, even politically, and their audiences will move on.
http://www.desmogblog.com/why-hard-core-climate-skeptics-don-t-change-their-mindsby Chris Mooney
I’ve been watching with interest the blogosphere uproar over... more
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