There he was, gnomically staring out from the cover of the March 29, 2009, New York Times magazine. The accompanying article proclaimed Freeman Dyson as a global warming heretic. Was he actually allying himself with the know-nothing, business-as-usual conservatives who viewed the climate-change scare as a great mistake or, worse, a hoax? The article provoked letters to the editor and a squall of pelting blog entries, some calling Dyson a fool, others extolling him as a heroic defender of scientific freedom.
In the aftermath of the Times piece, Dyson didn’t back down from his public distrust of mainstream attitudes on carbon, but he did admit that he was not an expert. The subject of global warming represented only a small part of his interests, he said. He didn’t want a leading role in the climate debate. That was the job for younger researchers. He would not, however, shy away from stating his views on so important an issue.
What bothered him the most, perhaps, was what he perceived as a growing intolerance among his scientific colleagues for unorthodox opinions. Some scientists who should have maintained a rigorous standard of proof when it came to interpreting data were being led astray by charismatic figures, and then blamed others who refused to join them. Dyson asserted that Al Gore—whose movie An Inconvenient Truth was a cause célèbre—wasn’t just being alarmist but had become the chief propagandist for, or the high priest of, the secular religion of climate change, a belief system in which scientific facts are trumped by politics.
It’s worth pointing out, as the Times article does, that Dyson himself is in many ways a typical, Obama-supporting liberal. He had long sought to reduce and eliminate the United States’ inventory of nuclear weapons. He regularly contributed to the election efforts of Democrats. So how did he end up on the wrong side (as many of his scientific friends would say) of the carbon issue? Not surprisingly, the saga of how Dyson came to hold his climate views is complicated.
First of all, Dyson doesn’t believe that the climate issue is a gigantic hoax. He doesn’t deny that carbon dioxide in the atmosphere is rising and that human activity is largely to blame. He doesn’t deny that climate is changing or that some bad consequences will follow. He does say, however, that some of the changes might be good. Warmer temperatures would, for example, extend the growing season in many places.
His main objection to the consensus scientific view, encapsulated in the reports of the Intergovernmental Panel on Climate Change, is that it rests on poor data and faulty computer models. Dyson suggests that computer simulations of climate—which is another name for long-term weather—do an able job of accounting for carbon dioxide uptake in the sky and in the oceans but not in that other vast terrestrial sheath, the biosphere. He argues that forecasts of dire climate consequences—intensified droughts, floods, sea level rise—are not sufficiently firm to justify the large expenditures needed to slow carbon emissions.
But couldn’t we carry out those mitigation plans anyway, even if the models aren’t quite right? Shouldn’t we be cautious on a matter of such great importance? After all, we take out fire insurance on our homes even though the chance of them burning down is small. His answer to this objection is that undertaking an extensive (and expensive) program of carbon mitigation will distract society from other ills that loom larger: hunger, poor public health, illiteracy, poverty, corruption, and war. Each year millions succumb to these blights.
In the years leading up to the New York Times piece, Dyson published numerous review articles guardedly expressing his climate views. Only when the Times piece appeared did his apostasy become well known. Amid the furor that followed were many assertions that although Dyson might be smart, he wasn’t smart on this topic, and that he should mind his own business.
This turns out to be untrue. As early as 1972 and for several summers thereafter, he worked at Oak Ridge National Laboratory in Tennessee with colleagues such as Jack Gibbons (later President Clinton’s science advisor) on early computer climate modeling. Doubts arose in his mind even then about the efficacy of modeling and the quality of soil data. He felt that the carbon problem (as it was beginning to form in scientific circles, if not yet in the larger social consciousness) had more to do with soil management than with atmospheric mitigation. In short, he believed that the extra carbon injected into the air when we drive cars and make electricity by burning coal could be halted by growing more trees. He differed strongly enough from his Oak Ridge colleagues that he wrote a “manifesto” about agricultural scheme. In a 1977 journal called Energy, he suggested that a hypothetical rise in atmospheric carbon dioxide might be addressed by capturing it with trees or swamp plants bio-engineered to grow larger roots. The roots, he said, would incorporate the carbon dioxide. This carbon would stay put in the form of new topsoil.
Here, from that article published a third of a century ago is Dyson’s skepticism speaking out:
There exists a huge literature attempting to assess or to prognosticate the effect of the increasing atmospheric CO2 on the climate of the earth. Such attempts are useful and necessary, but they run into formidable technical difficulties. Even the mean global temperature rise caused by a given quantity of CO2 is subject to great uncertainty.
Dyson is a mathematical physicist by training, but much of his mature career has been spent preaching on a variety of subjects, including nuclear weapons, science and ethics, and the origin of life. He is not a fiery orator. Instead he tries to persuade his audience quietly, through logic and anecdotes.
One of his favorite topics is the effect of technology on the environment. So, let’s take up the question of the hour: how can climate change brought about by human intervention be good? Dyson has been rehearsing an answer for several decades. For example, in a 1974 speech at an energy meeting in Madrid, he pointed to several examples of past or future environmental modification: a greener England, a wetter Sahara, and a warmer Siberia. First, England: this demi-paradise, the land of Dyson’s birth, with its gardens, farms, and pastures is, he says, utterly unnatural. The forests and swamps of primordial England have been made over into an artificial ecology to suit the needs of its human inhabitants. Dyson doesn’t deny the possible dangers in fooling around with nature, but feels that we shouldn’t ignore the possible benefits of climate or habitat modification. We should weigh the good with the bad. As for a wetter Sahara and a warmer Siberia, Dyson says this could represent a possible doubling of the arable land on Earth.
Plants regard carbon dioxide as food. With the help of sunlight from the sky and water from roots, plants turn carbon dioxide into oxygen and carbohydrates. At a 1990 lecture in Oxford, Dyson provided a vivid picture of the energetics at work. On a sunny day at noon, he said, a stand of growing corn drinks in all the available carbon dioxide within a meter of the ground in about five minutes. (Further carbon dioxide arrives because of general air circulation.) Food yield should go up with any increase in the amount of carbon dioxide in the atmosphere. This has been demonstrated for greenhouse experiments but not yet for crops raised in open fields. Dyson is eager for more data in order to see how much of our carbon excess can be absorbed into growing vegetables or creating new soil.
Global warming, Dyson likes to point out, is not global. Warming is much more pronounced in dry places than in wet, in cold places more than warm ones, in polar areas more than tropical, at night more than during the day, at high elevations more than in lowlands, and in winter more than summer. These disparities make climate change hard to pin down as being one singular thing to be dreaded or corrected at great cost. How can we cure the patient if we haven’t yet diagnosed the illness?
Remaking nature is exactly what the human species has been doing since the advent of agriculture 12,000 years ago, Dyson insists. Animal husbandry, the culling of grain species, the diversion of rivers, the burning of forests, and in-vitro fertilization are just a few of the large-scale human interventions. Many plant and animal species in England now are non-native. Pollution and other technological depredations are still problems in some areas, but major strides have been made in cleaning up cities and rivers, and England is again a pretty good place to live, despite many layers of artificiality. The existence of Green England led, with the help of artificial fertilizer, to the possibility of Green India. Fertilizer in excess does harm, but in moderation it can and does feed millions.
So Dyson suspects that the problem of greenhouse warming is not as grave as many believe. Furthermore, if the atmospheric excess of carbon dioxide is indeed serious then it can probably be addressed by introducing trees and other plants with a much larger carbon uptake—a larger roots-to-shoots ratio—than present species can accommodate. But what if bioengineering or other mitigation schemes aren’t up to handling the great carbon burden? Then we might just have to confront a great social divide—one not mentioned in the Times article.
This is the prospective conflict between naturalists and humanists. These two communities overlap considerably and many adherents would be reluctant to have to decide between these two worthy isms. In Dyson’s view, feeding people comes first.
If people do not have enough to eat, we cannot expect them to put much effort into protecting the biosphere. In the long run, preservation of the biosphere will only be possible if people everywhere have a decent standard of living. The humanist ethic does not regard an increase of carbon dioxide in the atmosphere as evil, if the increase is associated with worldwide economic prosperity, and if the poorer half of humanity gets it fair share of the benefits.
Dyson may talk about the “humanistic ethic,” but this isn’t classic humanism; his humanism doesn’t rest upon the Enlightenment thinking of Voltaire or Burke or Madison. Rather, it rests upon energy flows, crop yields, genetic improvements, and landscape revisions. Also, Dyson’s use of the word “evil” is not theological. He dislikes theology. Instead he means something more like foolishly counter-productive. What he values are good engineering and utility.
But could the solution to warming really be that simple? China burns coal to make electricity, while on the other side of the Pacific, the United States captures carbon dioxide to make dirt? And what of the difference between short-term and long-term utility, one might ask. Isn’t Dyson being short-sided? By feeding those alive now we might be choking those who will be alive a hundred years from now. Dyson’s answer to this objection is often to say that unanticipated technological innovations and new scientific insights will rescue us from seemingly intractable problems.
Can we count on these future technological innovations? Many scientists, even those who count themselves as Dyson’s friends, say that his optimism might be misplaced, and that he overestimates the ability of bioengineering to produce new plants that store more carbon in their roots. Some critics go further and say that Dyson gets facts wrong and that computer models are much better now than they were during his summers at Oak Ridge. One recent study published in the journal Science, for example, shows that crop yield does not go up for increased levels of carbon dioxide.
As a scientist, Dyson ought to amend his views as new information becomes available. But the heretic is not recanting. No new carbon data or improved climate models have persuaded him to change his mind. We can try to reduce our use of fossil fuels, he says, but if the unwelcome choice lies between people starving or keeping the coal-fired generators running, then keep burning coal.
This argument seems all the more contradictory coming from a man who has several times written and spoken about the differences between what he calls green and gray technology. Physics, factories, plutonium, bureaucracy, he says, are gray. Biology, gardens, manure, and pioneer communities are green. He makes sure to say that gray things are important; gray thinking has facilitated many good things, such as Newton’s laws of motion, modern medicine, fast transport, higher literacy, and more food. But in the long run, he asserts in his 1979 book Disturbing the Universe (in a chapter called “The Greening of the Galaxy), green things hold a higher promise of making the world more livable. A reader gets the feeling that Dyson roots for green over gray.
So, is Dyson a naturalist or humanist? Having set up several dichotomies—green vs. gray and humanist vs. naturalist—Dyson tries to reconcile them, or at least enunciate the nature of their divergence:
Naturalists believe that nature knows best. For them the highest value is to respect the natural order of things. Any gross human disruption of the natural environment is evil. Excessive burning of fossil fuels is evil. Changing nature’s desert, either the Sahara desert or the ocean desert, into a managed ecosystem where giraffes or tuna fish may flourish, is likewise evil. Nature knows best, and anything we do to improve upon Nature will only bring trouble.
The humanist ethic begins with the belief that humans are an essential part of nature. Through human minds the biosphere has acquired the capacity to steer its own evolution, and now we are in charge. Humans have the right and the duty to reconstruct nature so that humans and the biosphere can both survive and prosper. For humanists, the highest value is harmonious coexistence between humans and nature. The greatest evils are poverty, underdevelopment, unemployment, disease, and hunger, all the conditions that deprive people of opportunities and limit their freedoms. The human ethic accepts an increase of carbon dioxide in the atmosphere as a small price to pay if worldwide development can alleviate the miseries of the poorer half of humanity. The humanist ethic accepts the responsibility to guide the evolution of the planet.
We’d like to say this is a false dichotomy. But then wouldn’t we too, like Dyson, be guilty of wishful thinking, hoping or expecting that technological fixes (wonderful alternative energy sources that allow us to cut back on the use of fossil fuel) will rescue us from having to choose between mass starvation and climate catastrophe?
Dyson is almost surely wrong, scientifically, about the good consequences of current climate change outweighing the bad. But he is not wrong to insist that two billion Chinese and Indians should aspire to live as well as Westerners. How to accommodate these aspirations into a working model for global civilization will probably be more difficult than reducing carbon dioxide emissions.
One can compare Dyson’s climate dilemma to another drama. In Henrik Ibsen’s play, An Enemy of the People (1882), set in a small Norwegian town, a moralistic doctor helps to develop a system of therapeutic baths that, so everyone in town hopes, will soon bring wealth to the townspeople in the form of a lucrative tourist trade. Then the doctor discovers that the water system is polluted. He takes this news to his brother, the town’s mayor. The doctor is shocked when the mayor tells him to keep the news to himself. The doctor does not keep it to himself and instead indignantly goes to the public with his (admittedly unwelcome) revelation. Rather than being heralded for his honesty, he is shunned as a troublemaker.
If we were recasting this story as the pursuit or questioning of inconvenient scientific truths about climate, how would we assign the parts of mayor and doctor? What part would we give to Freeman Dyson and which to Al Gore?
Of course this is a silly comparison to make. Both Gore and Dyson seem to be honestly confronting the same set of facts. Neither one of them is an enemy of the people. Many humanists and naturalists alike have respect for the accomplishments and courage of both the former vice president and the professor. But they can’t both be right on the issue of climate change. Or maybe it’s more apt to say that one of them doesn’t necessarily have to be wrong. The uncomfortable reality is that because of the importance of this issue, endless deliberation is not an option. Long before definitive scientific facts can be delivered, legislators, businesses, and citizens will have to decide on a course of action.