Monday, December 21, 2009

Doing science in a greenhouse

The recent furor surrounding the hacked e-mails from the Climate Research Unit (CRU) at East Anglia University has died down a good bit, but the effects of it will reverberate for a long time The e-mails reveal a good bit of small-minded belligerence toward some scientists whose views depart from the consensus position, and speak of excluding some of their work. The director of CRU, Phil Jones, has stepped down pending an investigation of the episode. Pennsylvania State University said it would review the work of Michael Mann, a faculty member cited prominently in the e-mail messages, to assure that it meets proper academic standards. Climate change skeptics have seized upon the disclosures as demonstration of what they have been saying all along, that the science behind the claimed anthropogenic changes to climate is dubious at best. Republicans in Congress are calling for investigations into the work of US scientists any way connected, inasmuch as they are likely to be supported by federal funds.

What can this episode teach us about the nature of scientific authority? Clearly the authority of many scientists identified in the e-mails has been substantially weakened, and, by association, that of the climate science community more generally. Analysis of this particular case can help us understand more clearly the boundaries between science and other social sectors, and point to how scientists should behave to sustain science’s proper societal roles (See Steven Shapin’s excellent essay on this subject, and the discussion in Imperfect Oracle).

Michael Gerson wrote in the Washington Post on December 11 about the melding of science and politics. In the interests of advancing the case for urgent responses to the threats represented by climate change, some prominent climate scientists “..appear to exaggerate their public certainty on disputed issues, shade the presentation of information for political effect, tamper with the peer-review process, resist reasonable requests for supporting data ..” He speaks of the insularity of the climate science community: “Climate scientists are clearly accustomed to deference. Theirs is a community coddled by global elites, extensively funded by governments, celebrated by Hollywood and honored with international prizes. But outside the Copenhagen bubble, the field of climate science is deep in a crisis of professional credibility, which many scientists seem too insular to recognize.” Gerson is not a climate change skeptic. His concern is that scientific objectivity seems to have been compromised by a drive for political and economic change: “But without trust in disinterested, scientific judgments on climate, most non-scientists will resist costly, speculative, legislative actions. When the experts become advocates, no one believes the experts or listens to the advocates.” He concludes that the climate scientists involved in the episode have diminished the authority of science more effectively than anyone else could have.

But Gerson’s position borders on saying that scientists’ expert authority is compromised whenever they move beyond the boundaries of their expert, or epistemic, authority to argue for what should be done in a given situation, as opposed to what is simply the case. In fact, there is a hierarchy of positions involved. At the first level the scientist is an expert, and exercises epistemic authority by reporting as objectively as possible on the scientific results. In the present case, climate scientists might offer expert opinions on the potential for climate change based on vast amounts of data accumulated on various aspects of the climate, and with the aid of extensively tested computer modeling of what future climate will look like given particular scenarios of fossil fuel use. If those opinions are a realistic representation of what the science community holds to be the case, we have a straightforward example of the exercise of epistemic authority. Beyond this a scientist can exercise moral authority, by moving beyond offering an expert scientific opinion to advise that a particular course of action be taken; in the present instance, to advise that certain policies should be established to mitigate the harmful effects of climate change. This effort to exercise moral authority presupposes the epistemic authority of the scientist. The scientist’s expertise plays a role, but in the broadest sense of making a moral judgment the scientist is no better positioned than anyone else in arguing for what actions should or should not be taken. A non-scientist acquainted with the results of the scientific studies might argue that, assuming a doubling of the carbon dioxide content of the atmosphere will result in an increase in the Earth’s surface temperature sufficient to cause much human travail, we should stop burning fossil fuels quickly as possible. In advancing the same argument, a climate scientist's view should not count for more than the non-scientist’s, since both are premised on the same scientific considerations. It's not that the scientist’s expert authority has been weakened, it is simply not the driving influence; in making the moral judgment the science is taken as a given, equally available to both scientist and non-scientist. Beyond this, the scientist and non-scientist alike can move to active advocacy in the public domain for the particular actions that were advised in the exercise of moral authority. In moving into this kind of advocacy, the scientist surrenders her credentials as a scientist; those have already been cashed out.

This of course all seems quite reasonable in the abstract, but when the topic is as huge, urgent and plagued with manifold complexities as climate change, distinctions become blurred. The differences between these different stances with respect to an issue of such wide social importance are not sufficiently appreciated, particularly by scientists. There is nothing inherently wrong in scientists getting caught up in political advocacy for causes that grow out of their scientific work. When they do so, however, they must reconcile themselves to the loss of much of their scientific expert and moral authority. When the arguments are flying back and forth as to what should be done, advocacy for particular courses of action is already premised on knowledge that is taken as a given. If the scientific basis for the argument is contested, we are back at the stage of shoring up expert authority. In the case of climate change, Senator James Inhofe, Glenn Beck and their ilk keep wanting to return the argument to that first stage. It has been tempting for climate scientists to depart from norms of objectivity and disinterestedness in the interest of protecting and enhancing their epistemic authority. But doing so has proven embarrassing for some, and damaging for science’s image as a reliable, trustworthy source of knowledge. Disagreements within the climate science community over data interpretations, adequacy of the models and the reality of human effects on climate are being thrashed out in a glass house. A lot of people are watching; science’s epistemic authority is being determined by what non-scientists can see of how science moves toward increasingly reliable knowledge. Climate scientists can help keep the focus where it should be by not providing further unfortunate diversions.

Saturday, December 12, 2009

The costs of fossil energy

We’ve known for a long time that the energy we need to keep society running costs us more than just the market price. There is also the price of repairing damage wreaked upon the environment and collateral impairments to human health. Think, for example of coal, the largest single source of energy for generation of electrical power. Coal mining typically makes a sorry mess of the environment. To get at the coal the terrain is ripped up, so pristine countryside is denuded. The residues left exposed to the weather leach out chemicals that change the acidities of streams and lakes, killing fish, often poisoning wildlife and rendering the water unfit for human consumption. As though that were not damage enough, the coal that is combusted in the power plants is contaminated with trace metals such as mercury. These find their way into the gas plumes from the plants to create health problems for those who live within a large radius. The sulfur in the coal is emitted as sulfur dioxide, which adds to the acidity of the atmosphere and is a health hazard in its own right. But the coal industry is very powerful; it can afford ads that reassure you that we are a safer and more prosperous nation because we can rely on coal as our very own energy source.

We are soothed even more by ads that claim that natural gas is a huge, clean source of energy, one that will serve us well for decades to come. It certainly burns more cleanly than coal, and may add less greenhouse gas to the environment than coal per unit of derived energy. But there seems always to be a dark side to each of these energy types. A recent article in the New York Times reinforces what we have been learning from other sources: that new technologies for freeing up natural gas in shale formations, called hydraulic fracturing, cause disturbances to the underlying strata that end up compromising water supplies vital to those who live in the environs. It can get pretty bad; for example, wells that are sufficiently contaminated with methane that they explode on contact with an igniting source. Furthermore, the water is also polluted with toxic chemicals used in the fracturing process.

Well, then, how about those tar sands up in Alberta, a huge and largely untapped source of fossil fuel energy? To learn more about the costs, environmental and otherwise, of extracting useful energy from the sands, read Elizabeth Kolbert’s 2007 report in the New Yorker magazine. What is being done to the environment in that quest for yet another source of fossil energy can make one ill. I could go on with more stories of our desperate quest for fossil fuels, such as deep drilling on the ocean floor; incredible technologies employed in ever riskier attempts to obtain fossil fuels. Every success, however limited, and at whatever price in terms of human health and environmental damage, helps lull us into thinking that we needn’t make special efforts to develop alternative sources of energy – solar, wind, new battery technologies, and yes, nuclear energy - that hold the promise of releasing us from our dependence on fossil fuels.

All of this is bears on the intense discussions presently being waged over the reality and extent of climate change. As Thomas Friedman recently pointed out, the details of the climate change debate are really not material to the larger issue of making ourselves less dependent on fossil fuels for the health of our economy and the prospects for a more livable world. Humankind has somehow to negotiate a very difficult transition in the decades ahead: creating a world society that is more balanced in terms of living standards, living more efficiently in terms of resource utilization, and bringing the human population to equilibrium at a number that the planet can sustain. Shouldn’t we in the United States be leading the way?

Saturday, December 5, 2009

Science with its pants down

Because the consequences of a human contribution to climate change are huge, scientific research that could shed light on this question is very important, and has risen to high visibility all over the world. Thus it has come to pass that a scandal of sorts in the world of climate science, referred to by some as “climategate”, has drawn a lot of attention.

I need not rehearse here the saga of the past couple of decades of intense debate over the question of whether humans are causing climate change. The implications for the workings of modern society are enormous. If it were the case that fossil fuel emissions are causing an increase in the temperature of the planet, and if that increase has the potential to cause disruption of society at many levels, a world-wide effort to mitigate that increase would be called for. We have had a succession of reports from the Intergovernmental Panel on Climate Change (IPCC), each presumably updating and improving upon its predecessor, that point to a likely increase in global temperature over the next 50 to 100 years. The predictions point to alarming changes in weather pattern s, and a potentially disastrous rise in sea level, along with a host of other changes that would require great adjustments in human society. So we are coming up to the Copenhagan conference, at which the nations of the world are once again under great moral pressure to respond to this threat. The costs of effective mitigation will run into the trillions of dollars.

On November 20 some files and e-mails originating in the Climate Research Unit of East Anglia University were made available publicly, by whom or by what means I don’t know. For those who have read the files and dug into some of the background, what they reveal is not a pretty story. Meagan McCardle summarized some of her conclusions and reactions in Atlantic magazine on December 1. What emerges from the discussions of this episode is that influential climate scientists at this very prominent voice of expertise on climate change appear to have behaved badly in several respects. They exercised undue power over the peer review process on papers dealing with climate change, and thus were able to stifle work that did not meet their well baked-in ideas of what is happening in the field. Here is a quote from one of the e-mails uncovered:
“I can't see either of these papers being in the next IPCC report. Kevin and I will keep them out somehow - even if we have to redefine what the peer-review literature is !”

An even more serious problem has to do with the quality of much of the historical data on which the modeling studies depend. Climate models are tested in part by their capacity to produce temperature and other trends that match the historical data. It now emerges that the original data sets are nowhere to be found! The problem is that many of the older data have been adjusted for one reason or another over the years, by persons unknown, and for reasons that were not well documented. Much of the original computer code is formatted in computer languages no longer in use, and backing out the original data is maddeningly difficult if not impossible. These data are the source of what eventually becomes an estimate of the global temperature. So we have the situation that the historical record of the planet’s temperature is now in disarray, and may not even exist!

This episode is very distressing to me as it is to all who want to see science respected as a reliable and truthful source of knowledge of the world. I’ve written in Imperfect Oracle of the ingredients that make for science’s epistemic authority. I won’t recite all that here, but clearly truthfulness and a disinterested approach to one’s work are key ingredients. However, aside from what appear to be serious lapses from professional ethical standards, something else about this case strikes me as especially interesting. The reactions to this story would have one imagine that that original historical record of the global temperature is somehow sort of gold-plated scientific data, the true story of the planet’s temperature over the past 150 years. I believe that to be false. At best, much of that record is quite unreliable and subject to uncertainties that are much larger than the variations that are being talked about.

I wrote about the concept of global temperature in a book published in 2003, Making Truth: Metaphor in Science, (see pages 163-165). As I pointed out, there is no physical thing that corresponds to the global surface temperature, or at least there has not been to this point. Measuring the earth’s temperature is not like sticking a thermometer under the tongue and getting a measurement that is satisfactorily representative of the temperature regime throughout the entire body. When the tongue thermometer registers a change of a degree or two from the normal, the fact of that temperature change is evident in the way the person feels: feverish. There is no analog to the under-the-tongue thermometer in measuring the surface temperature of the planet. Until the advent of satellite measurements which only now are becoming well enough standardized to serve as a reliable measure, climatologists relied upon a patchwork of measurements non-uniformly covering the planet’s surface, many of them individually unreliable, which was then somehow put together to give a number we call the global temperature. In truth, it is a sad fact that this idea of a reliable global temperature has been sold by climatologists with scarcely any acknowledgement of how sketchy it really is.

It is important to note that the absence of a reliable historical record of the planet’s surface temperature does not render impotent the idea that the planet is warming. Suppose you had an unreliable thermometer for measuring your body temperature. Even if the device did not give you a reliable measurement, you would know if you had a significant fever, right? In the same way, it is evident from what we see occurring in nature that the planet is growing warmer: disappearing arctic ice, glacial melting, shifts in weather patterns that clearly betoken warming in both hemispheres. The big issue, however, is whether and to what degree this warming is due to human activity. This is where climate modeling comes in. If they are sufficiently complete and self-consistent, the very large, complex computational programs that the climatologists have produced should be able to tell us how much change in surface temperature could be accounted for by greenhouse gases added by human activity. But are the models sufficiently realistic ? One way to test this is to see whether they reproduce historical climate change. Also, though I am unsure about this point, the programs may need the historical data for some aspects of the computations. But if we don’t have a reliable, sufficiently complete historical record…well, climate science has a credibility problem.

This episode has dealt a blow to science’s epistemic authority, and to its moral authority as well.