Jesse Ausubel directs the Program for the Human Environment at Rockefeller University in New York City. Ausubel, with degrees from Harvard and Columbia, has long worked on environmental issues. In 1979, he was one of the main organizers of the first U.N. World Climate Conference in Geneva, and in 1983 the lead author of Changing Climate, the first comprehensive review of the greenhouse effect. Over the past two decades he has been involved in research projects ranging from the health of forests to an ongoing international effort to assess the diversity and abundance of ocean life. In July, he published “Renewable and nuclear heresies,” heretically declaring that “renewable sources of energy are not green and that the nuclear industry should make a product beside electricity.” Ausubel corresponded with Robert Bryce via e-mail in early August.

ET: Your paper “Renewable and nuclear heresies” has been attacked by the left and lauded by the right. The left says you are ignoring the threats of global warming while the right points out that you don’t like renewables. What is your position on the viability of carbon dioxide emission reduction efforts like Kyoto?

JA: I do not think energy policy matters much over the long run. Certainly diplomats do not reduce greenhouse gas emissions. In general, politicians are pulling on disconnected levers. My skepticism about public policy angers left and right about equally. The evolution of the energy system is driven by the increasing spatial density (watts per square meter) of energy consumption at the level of the end-user. The increasing spatial density drives the system towards gas and electricity and the energy sources that enjoy economies of scale in producing them

ET: In reading through your recent publications, you don’t talk about global climate change much. Why not?

JA: I was deeply involved in the late 1970s and early 1980s in the modern formulation of the climate change issue. Continuing and accelerating decarbonization is one of the two great environmental challenges, along with sparing land and sea for nature. But I think climate change has been an intellectually solved problem since 1990 or so. I have little to add, and I find few new ideas, especially in relation to the huge expenditure on research during the past couple of decades.

ET: You have been writing a lot about the decarbonization of the global fuel mix and the trend toward increased natural gas consumption. Why do environmentalists ignore the benefits of methane?

ET: What, if anything, should the government be doing to stimulate progress on the trends that you have described: decarbonization, increasing energy density, smaller electric generation plants, etc.?

ET: You are pro-nuclear. Do you favor building more nuclear reactors of the current design (pressurized water) or do you prefer the new technologies (pebble bed, etc.)?

JA: Both. For the next 30 to 40 years, the main model will be the one people know how to build and service. The present designs work fine. But I look forward to scalable high-temperature gas-cooled reactors that can also produce hydrogen, becoming a common purchase.