on his public policy hat" and spends an average of 3 days a month in Washington, D.C., translating and transmitting the science into its political context.

Explained McRae: "The role of the science is to try to understand what is going on in the atmosphere, and that involves three things: the chemical interactions that take place in the atmosphere, the emissions from mobile and stationary sources, and the meteorology that moves the materials around," The traditional role for atmospheric science has been, "given these inputs, to unravel the science that governs what happens, and to predict what will happen." Very often, however, the political process involves other nonscientific goals that inevitably color the way an atmospheric scientist works, often influencing his or her charge and data-gathering focus. "Atmospheric science is not practiced in isolation. The whole air-quality planning process involves science as well as social issues," according to McRae, who emphasized that scientists not only need to think about doing good science and engineering, but also need to venture a little beyond just the science and think about what that work and the results really mean to society. "With a bit of luck," he added in his presentation to the symposium's scientists, ''we might perhaps convince you that that is an important thing to do.''

McRae is a chemical engineer with what he described as "a fairly simple-minded view of the world, [the need for] what I call getting the sign right." To illustrate, he discussed chlorofluorocarbons (CFCs), engineered to be "extraordinarily good materials" and a very useful industrial product. But because of their particular chemical nature, CFCs turned out to have an unanticipated negative impact on stratospheric ozone. Millions of dollars were spent to create CFCs, but millions more will be spent to eliminate them and to mediate their adverse effect on the atmosphere. Thus there is a need, McRae emphasized, to go beyond concentrating on the physics and chemistry of how to make new materials and to think also about "the impact and pathways of chemicals after they leave the lab." McRae is also sensitive to the possibility that studies to elucidate phenomena in the atmosphere may not be balanced with a search for control strategies to deal with them. The urgency that attends the problems of pollution, he thinks, confers a responsibility on atmospheric scientists to consider issues like cost-effectiveness and adverse impacts whenever their results might be central to a political debate, which—in atmospheric science—is very often.

McRae has developed this awareness of the political arena as his model—begun in graduate school at Caltech—has evolved using a historical database of Los Angeles weather and pollutant data. That



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement