Saturday, December 10, 2011

Yep, it's getting warmer


In a recent issue of Science a trio of scientists who are experts on climate modeling and interpretations of data related to global climate summarize the best available information on variation in Earth’s surface temperature over the past half century or so. Their work addresses a controversial subject that those resisting the idea of global warming love to talk about.
Doubts about the reality of 20th century warming have been fueled by a veritable blizzard of misinformation and outright denial by politicians such as Senator James Inhofe and talk show hosts such as Rush Limbaugh and Glenn Beck. The political winds from the extreme right have been blowing so mightily against the notion of global warming that the front-runners in the race for the Republican nomination in 2012 seem to be obliged to join in the denialist chant. The American people are being deluged with misinformation and outright lies on this topic. It is thus worth thinking about the significance of this recent work by Santer, Wigley and Taylor.
One of the most difficult challenges in the entire business of drawing conclusions about Earth’s surface temperature is that there really is no single literal measurement that gives us the temperature of the planet. I wrote about this in Chapter 9 of my 2003 book, Making Truth: Metaphor in Science. When we want to measure our own body temperature, we insert a measurement device such as a thermometer, or one of the fancier digital probes, under our tongue, in our ear or up our rectum, as the case may be. The temperature we record in this way we take to be representative of our body as a whole. This works because our bodies are designed to maintain, as closely as possible, a single temperature throughout. But planet Earth is not like that. As I write this in Estero Florida the temperature is about 80 degrees Farenheit. At the same time, my daughter living in mid-central Illinois reports that the temperature there is about 11 degrees Farenheit. It is far colder still in Antarctica. No single value represents the surface temperature of the planet . For this reason, when we talk about the surface temperature of the planet we are using metaphorical language and thought. We talk aboutEarth’s surface temperature as though the planet were a small, temperature-controlled thing like a human body or a refrigerator.
To get to something that resembles a single value for the surface temperature, scientists began with simply averaging the temperatures measured at as many places as possible at the same time, and averaging over time as well. Before the modern age of satellite measurements the estimates were pretty crude. Consider that something like 70 percent of Earth’s surface is covered with water. How do we get sufficient measurements of the vast and varied seas to produce reliable numbers? And what about remote places that are not readily accessible, or crowded urban areas where human activity generates a good deal of local heat? With satellite measurements it has become possible to collect data over a short period of time that reflects surface temperatures
over most of earth’s surface. By averaging these in a suitable way, one ends up with a single number that we call the surface temperature of the planet. It’s a metaphorical entity, not a real single temperature, but its value over time can serve as a reliable measure of the change at Earth’s surface. However, the interpretation of satellite data is not entirely straightforward. A group of scientists at the University of Alabama at Huntsville concluded in 2005 from satellite data that the planet’s surface temperature had declined since 1979. This unexpected result was used to cast doubt on the reality of surface warming.
One of the hallmarks of good science is that controversial results are subject to reevaluation and continued exploration. The satellite measurements were a new technology, and many factors needed to be taken into account in interpreting the data. Climate scientists at a California laboratory identified two serious errors made by the Huntsville group in their analyses. These were acknowledged by the Huntsville scientists, who redid their recalculations. The corrected results showed a warming trend over the entire period 1979 to present. The revised estimate, following from critical scrutiny by other scientists, represents another step forward in our ability to measure and understand the evolution of the global climate.
Modeling the terrifically complicated global climate system is difficult. The challenge is to find a model that reproduces the historical record as well as possible, considering all the uncertainties,and then to use that model to forecast the future course of climate change, assuming various scenarios regarding levels of greenhouse warming gases, energy consumption, population growth and so on. The media are filled with confident pronouncements, for the most part self-serving, about climate change from political, ideological and financial interests. When we hear what people like Rush Limbaugh, James Inhofe or Newt Gingrich are saying or are ready to get behind, we need to ask what motivates them and what is their competence to speak on the issue at hand. We should also do that with respect to scientists, whatever the issue might be. Citizens need to go behind the one-liners of politicians and talk show personalities to learn what scientists think and the evidence that supports their views. There is no scientific conspiracy to deceive the public into believing that global warming is real, and that it has the potential to cause a great deal of human suffering. Scientists are just doing their work, trying to learn more about the way the world is.
An incredible amount of research across many scientific disciplines leads to an unambiguous result: the planet is warming, mostly because of increased concentrations of so-called greenhouse gases in the atmosphere. Denying this may be politically or financially expedient, but global warming is underway and it will gain strength with each passing year. How much adverse change occurs over the next 50 years and beyond will depend on whether humanity collectively decides to do something about continued generation of greenhouse gases. There is little hope for significant action in the near future. The 2011 Climate Change Conference in Durban, South Africa, just concluded with essentially no progress in setting mandatory goals for reductions of greenhouse gases. This should not surprise anyone. We humans have evolved to possess a strong consciousness of the future, but we still live very much in the present. Our proclivity to discount the future, particularly one so distant that we will not be there to live in it, prompts us to choose present needs and desires over future consequences of our actions. That seems to be the way it is with respect to climate change. As Kurt Vonnegut was fond of saying, “So it goes…”.

Sunday, September 4, 2011

Attacking the Messenger



The lay public’s trust in the work of scientists generally is eroded when there is evidence of fraud or another form of ethical lapse by any scientist or group of scientists. As I’ve written in Imperfect Oracle: The Epistemic and Moral Authority of Science, science’s capacity to exercise authority in the affairs of society is grounded on the presumption that scientists speak reliably and with good intent. This means that when scientists make claims based on their experimental or theoretical work, their representations of what they have found, and the conclusions based on them, are as full and true as they can make them.

For the most part, scientists share their work via talks and papers presented for the benefit of other scientists, in particular those working in the same or closely related fields. Individual contributions meld with others to form, over time, a more or less consensual understanding of what is going on in a given problem area. For that process to work individual scientist’s accounts must be as accurate and faithful to the findings of the research as possible. Futhermore, those individual accounts and claims must be subject to skeptical scrutiny by other scientists to ensure, insofar as possible, that they are correct. In this way, something that the philosopher and scientist Michael Polanyi called “scientific opinion” is formed. The epistemic authority of science as a voice in society’s affairs depends on a general acceptance of this idea. The process of vetting within the scientific community has the effect of producing stronger scientific accounts, but in addition it goes a long way toward rooting out fraud and unethical behaviors such as plagiarism.

A recent story of fraud within the field of chemistry may help to show how this works in at least one case. A former Columbia University graduate student, Beng├╝ Sezen, working under the tutelage of Professor Dalibor Sames, was found to have fabricated nearly the entirety of her doctoral thesis research. By the time her fraud was exposed, her thesis had been accepted, she had been awarded the Ph.D. degree and was the lead author on three research papers published in the Journal of the American Chemical Society, one of the most prestigious chemical journals in the world. Her thesis project dealt with a hot topic in organic chemistry. She seemed to have made some major breakthroughs in getting difficult reactions to occur in productive ways. She produced evidence in the form of spectra, analyses and so forth in support of her account. Sames, her thesis director, an up-and-coming young faculty member, was delighted with her work.

But there was a problem, uncovered by fellow graduate students in the Sames research group: no one could reproduce her results. Sames did not want to hear that Sezen’s work was suspect, and he was inclined to lay the blame for the failure to reproduce her work on the newer students. But Sezen’s labmates were more aware than Professor Sames that Sezen was committing fraud, and eventually they were able to convince Sames of that fact. A long and protracted investigation, involving a committee assembled by Columbia University, was undertaken. Because the research had been supported by federal research dollars, the Office of Research Integrity of the Department of Health and Human Services was involved, and eventually a notice was published in the Federal Register stating that she had falsified, fabricated and plagiarized research data in three papers and in her doctoral thesis. Her doctoral thesis was in due course revoked by Columbia University. Sames had to withdraw a total of six published research papers because no one could reproduce the work. His reputation has been severely damaged by the affair. For example, see the comments in the blog ChemBark.

Much has been written about this episode, but I wish to focus on what it might have to teach us about the trustworthiness of science. Sezen, a pathological liar, produced huge amounts of scientific garbage, and got away with it – for a time. She was extremely clever in forging data from other spectra, falsifying analytical results and so on. In the end, though, the fact that the work could not be reproduced, even though attempts were made by several graduate students, triggered the kind of closer look into her files, notebooks and other records that made the deceit completely evident. This case is small potatoes in the large scheme of things, but it serves to illustrate that fraud in science will be caught out eventually. Science does not owe its reliability to the fact that all individual scientists are error-proof or free of moral and ethical lapses. Rather, its organizational structure and ways of forming consensual scientific opinion lead to exposure of errors and fraudulent practices.

All of this has some relevance for the ill-considered criticisms of climate science by many who come to the discussion with biases against global warming based on partisan politics, economics or an ultraconservative aversion to anything that might suggest the need for collective, global actions. The likes of Rick Perry, Rush Limbaugh, Glen Beck, Newt Gingrich or Senator James Inhofe, collectively have no expert understanding of climate science. They also do not seem to understand how science actually works. This has not prevented them from declaring that global warming is some kind of scientific hoax. The community of scientists with expertise in one of the major areas of science, such as atmospheric science, oceanography , chemistry or meteorology, that bears in an important way on questions dealing with climate change, is huge, highly diverse and international in scope. Climate change is a very complex, difficult problem to attack. All these scientists working away at the part of the problem that falls within their expertise have to eventually pull together all the results and projections to produce a complete story. That has been done, and it continues to be done through international efforts as more and more evidence accumulates, and as the tools for making projections grow more reliable.

Given the best projections climate scientists can make there is plenty to be said about what we should or should not do. However, we cannot start talking about climate change with a childish pique that we don’t like what we are being told. The people I have mentioned above, and others like them, have nothing constructive to bring to the scientific aspects of the discussion, nor does it seem that they are interested in grown up considerations of climate policy. It’s sad that society’s responses to the challenges of climate change are held hostage to demagoguery, and self-interest. In time nature will deliver its verdict, and our grandkids can pass judgment on what we might have done.

Monday, August 29, 2011

Whose Moral Authority?






After a long hiatus I am back to blogging. I hope to keep up a steady rate of writing, on the order of one a week, perhaps more often. Since I last wrote a blog, a great deal has happened in the world of science and politics. What does not seem to have changed is the rate of clashes between a scientifically oriented view of the physical world and perspectives that see nature through the lenses of religiosity, a political perspective or some other form of anti-intellectual outlook. These alternative takes the physical world sometimes pay lip service to science, but deny science’s capacity to speak with authority on matters that present a challenge to preconceptions.

This seemingly perennial impasse is well illustrated by what Rick Perry, the governor of Texas, an announced candidate for the Republican nomination for US president in the 2012 election, had to say in response to questions from a woman and her son during a recent campaign stop in New Hampshire, as reported in the Huffington Post and elsewhere:
"How old do I think the earth is? You know what, I don't have any idea," said the Texas governor when asked about his position. "I know it's pretty old so it goes back a long long way. I'm not sure anybody actually knows completely and absolutely how long, how old the earth is." He went on to say that he regarded evolution as "a theory that's out there" and one that's "got some gaps in it." He added that in the Lone Star State both creationism and evolution are taught to students in public schools. He explained, "I figure you're smart enough to figure out which one is right."
The Texas Tribune expressed disquiet about Perry’s response to the evolution question, pointing out that the state of Texas has no specific curriculum entry for the teaching of creationism, and that in any case the Supreme Court in 1987 made it illegal to teach creationism in public schools, on the grounds that it would be equivalent to teaching religion. Perry may in fact have correctly stated what is actually taught in Texas schools; classroom practices are, after all, largely in the hands of the teachers. What is more important is what Perry’s responses reveal about his lack of basic scientific knowledge and his disregard for that lack in shaping his public persona. A further illustration of this is contained in remarks he made at a breakfast address before business leaders in New Hampshire, as reported in the Huffington Post and elsewhere. Asked about global warming he indicated that he did not believe in it, and referred to the idea as a scientific theory that has not been proven. He would not spend public funds in further research on the matter, or in mitigation of it: "I don't think from my perspective that I want to be engaged in spending that much money on still a scientific theory that has not been proven and from my perspective is more and more being put into question." He is also quoted as saying, "I think we're seeing almost weekly, or even daily, scientists that are coming forward and questioning the original idea that manmade global warming is what is causing the climate to change." Paul Krugman made several effective rebuttals to Perry’s absurd and false statements in a recent Op-ed. He attributes them to pandering to the no-nothing branch of the Republican party. However, as Richard Cohen wrote in the Washington Post, Perry may be pushing his luck on this topic. While mitigation of climate change through governmental actions may be a losing battle for those who want strong global responses to the threat, the idea that global warming exists is one of those memes that has gone viral, as it were. Outside a narrowing range of public opinion, it is becoming decidedly uncool to maintain that global warming is a myth.

To judge from the public record, Rick Perry’s brain is the domicile of many crazy ideas on a variety of subjects. We could search long and hard to uncover just what sources of authority he draws upon in arriving at his worldview, but there is little point in doing that. More importantly, Perry is not just any ignoramus; he’s a public figure with a strong record of running for elective office, who is now receiving a lot of attention on the national stage. A recent Texan predecessor, George W, spoke in a similar style of mangled syntax and lack of understanding of the history and operation of the physical world, and look where he ended up! What matters for the public good is that Perry’s misstatements about nature and the world of science, fitted to his ultraconservative ideology and the interests of his backers, lead to false claims being presented, for the moment at least, to large audiences . To the extent that Perry is seen as a viable candidate his positions on issues that should be discussed and decided upon with consideration for their scientific basis do matter.

Within a limited sphere there is room for optimism for a more influential role for science in forming public policy and governmental action. The Obama administration has been more progressive than its predecessor in promoting science and technology in both the areas of human resources and industrial R and D. For example, a big bet is being made on development and manufacture of advanced batteries, as reported recently in the New York Times. But at a deeper level, a real shift in the attitudes of ordinary citizens toward a rational scientific outlook, and away from reliance on superstition and demagoguery, eludes us. How could this be brought about? I’m sure that an answer is out there awaiting discovery. It may require capitalizing in some as-yet unrealized way on the ever-increasing presence of social networking and the sources of information that feed it. Whatever their origins and channels of delivery, society needs pervasive and reliable sources of epistemic and moral authority in matters regarding the natural world as effective alternatives to the narrow-minded, ultraconservative rhetoric that seems to dominate contemporary political discourse. In the contests for people’s hearts and minds science is not doing so well.

Paul Krugman ends his Op-ed piece as follows: “ [T]he odds are that one of these years the world’s greatest nation will find itself ruled by a party that is aggressively anti-science, indeed anti-knowledge. And, in a time of severe challenges — environmental, economic, and more — that’s a terrifying prospect.” That may seem a bit overwrought, but for those who strive for a society in which rational thought governs decision-making, it is also a call to greater participation. Whose moral authority will govern?