RICHARD B. ALLEY
Professor of Geosciences
Pennsylvania State University

Abrupt Climate Change — A Historical View of Our Future
The history of the Earth's climate is written in ice cores, tree rings, ocean sediments and other archives. Reading that record shows that large, widespread, often very fast climate changes have occurred repeatedly in the past, but have been rare during the short window in which humans developed agriculture and industry. These changes have had many causes, including variations in Earth's orbit, changes in the composition of the atmosphere and reorganizations of ocean circulation. Humans are now affecting the climate in many ways, and run the risk of flipping a switch that may trigger an abrupt change - before we can even learn where the switches are and how they might be controlled.

Richard B. Alley graduated from Ohio State University with a B.S. in geology and later earned a Ph.D. in geology from the University of Wisconsin-Madison. Alley teaches and conducts research on the climatic records, flow behavior and sedimentary deposits of large ice sheets, to aid in prediction of future changes in climate and sea level. His experience includes three field seasons in Antarctica and five in Greenland. He has served on a variety of advisory panels and steering committees for professional societies, the National Science Foundation, the Congressional Antarctic External Review Panel, and the National Academy of Science Polar Research Board. For his efforts, Alley received a Packard Fellowship, a Presidential Young Investigator Award and the Horton Award of the American Geophysical Union. In addition to publishing The Two-Mile Time Machine, his work has been featured on National Public Radio and in Scientific American, and he has served as an advisor former United States Vice President Al Gore.

ROBERT JACKSON
Associate Professor of Environmental Sciences and Biology, Nicholas School for the Environment, Duke University

Global Environmental Change — Back to the Future
Global environmental change presents both a challenge and an opportunity to researchers and to society. The challenge is to develop a predictive framework that is intellectually sound and
relevant to policy makers; the opportunity is to use basic and applied research to address today's pressing societal problems. Jackson will discuss the historical context of environmental change, including greenhouse gases and biodiversity. He will also present research examples from his lab on the global carbon cycle and examples from other researchers, highlighting important progress being made today and the many uncertainties that remain.

Jackson studied chemical engineering at Rice University and worked for the Dow Chemical Company for four years. He later earned M.S. and Ph.D. degrees from Utah State University in statistics and ecology and was a DOE Distinguished Postdoctoral Fellow for Global Change at Stanford University. He is currently a professor of biology and environmental studies at Duke University and head of Duke's ecology program. His new book on the environment, The Earth Remains Forever, was published last fall and his work has been featured on the BBC and National Public Radio and in the Boston Globe, the New York Times and USA Today. In 1999 he was one of 19 scientists honored at the White House with a Presidential Early Career Award in Science and Engineering from the National Science Foundation.

JILL S. BARON
Research Ecologist, United States Geological Survey and Senior Research Ecologist, Natural Resource Ecology Laboratory, Colorado State University

The Tyranny of Small Decisions — How Local and Regional Human Actions Add Up to Global Change
Most natural resource decisions are made locally: forested hillsides are denuded for fuelwood; rivers are dammed for water supply; farmland is sold for housing development. With six billion people on Earth and ever more effective engineering prowess, the collective outcome of many small decisions adds up to global-scale change. Baron will give examples of how land use change can alter regional and global climate; how modification and pollution of waterways worldwide increasingly affect natural ecosystems and our ability to extract goods and services from them and how introduction or displacement of species can lead to extirpation or even extinction. While global change is often equated with greenhouse gases and climate, the stunning human capability for resource manipulation is equally important for altering the global environment on which we and all other species depend.

Baron received her B.S. in botany and geology from Cornell University, a M.S. in land resources from the University of Wisconsin-Madison and a Ph.D. in Ecosystem Ecology from Colorado State University. She is currently an ecosystem ecologist with the United States Geological Survey and a senior research ecologist with the National Resource Ecology Laboratory at Colorado State University. Her scientific training has encouraged her to apply many tools toward understanding ecosystems processes — past, present and future. She serves on numerous advisory boards and review panels and has received achievement awards from the National Park Service, the USGS and the USDA Forest Service. In 2002 Dr. Baron received the Meritorious Service Award from the Department of Interior. Recently she published Rocky Mountain Futures: An Ecological Perspective, a book that examines the past, present and possible future human influences on the Rocky Mountains.