There is a glimmer of hope that the living systems on Earth may be able to mitigate the effects of a changing climate. In this public lecture, Dr. Peter Cox, science director for climate change at the Hadley Center for Climate Prediction and Research, addresses this subject. Cox discusses the complex interactions between the physical and biological elements of the Earth system, and how a brand new type of computer models called "Earth System Models" are being used to more accurately predict future climate change by taking into account these dynamic interactions. 

How can we better understand the future climate by investigating the past? As Ray Bradley explains, proxy records--things like tree rings, ice-cores, and sediment cores--offer an invaluable window into the past climate changes and their causes. Using this historical perspective, scientists can more accurately predict future climate change. In this talk, Bradley presents the careful detective work of paleoclimatologists and the implications of their findings for modern-day climate forecasting. 

Precipitation patterns in the American West are widely varied and lead to both tremendous floods and prolonged droughts, and understanding these variations is a key component in helping residents adapt to life in this region. In this lecture, Kelly Redmond, deputy director of the Desert Research Institute, discusses natural variability in precipitation patterns throughout the West and comments on the additional impact human-driven climate change may have on climate and water resources in the region.

The realization that society's reliance on fossil fuels is resulting in alarming changes to the Earth's climate is forcing people to evaluate a host of issues concerning energy consumption and its effect on the environment. This public event addresses these issues and endeavors to educate concerned citizens about the challenges that lie ahead. In the first half, David Keith, an expert on energy and professor at Carnegie Mellon University, describes the world's current consumption of fossil fuels and suggests future options for energy that will reduce greenhouse gas emissions. Keith presents the surprising idea that fossil fuel consumption can continue without its harmful side effects provided energy companies pursue carbon sequestration technologies, which Keith argues are both possible and practical. In the second half, Stanford University professor Steve Schneider talks about the challenging policy dilemmas presented by climate change in both the developed and developing world. As a possible model for pursuing environment-friendly policies, Schneider offers the case of Bhutan, a developing country that has favored environmental and cultural production over the material benefits of Western-style industrialization. This event is part of the Walter Orr Roberts Public Lecture Series. Recorded on July 25, 2000 in Aspen, Colorado.

Improvements in energy efficiency alone are probably insufficient to stabilize carbon dioxide concentrations and mitigate their global warming potential. In this lecture, Dr. Martin Hoffert, Professor Emeritus at New York University, demonstrates that a global transition to sustainable carbon-free energy systems must be initiated to avoid a "stabilization crunch" and to meet Rio Treaty implementation demands.

One of the most troubling forms of global change is the alteration of natural landscapes, which leads to habitat loss, invasive species, and diminished biodiversity. In this talk, Carla D'Antonio from the University of California, Berkeley provides an overview of how human activity is having a profound affect on natural living systems. Dr. D'Antonio argues that while society does pay attention to impacts that affect agriculture or other economic activities, it must become aware of the widespread changes that are degrading natural habitats and reducing biodiversity.

Dr. Stephen Schneider believes that in addition to the usual array of baffling scientific uncertainties, cultural, psychological and educational obstacles make these already difficult problems virtually unsolvable so long as we continue to deny their existence. In this lecture, Dr. Schneider, a professor from Stanford University and a public spokesman for global change issues, provides an overview of the science behind global change and discusses public resistance to its evidence. Dr. Schneider argues that in order to have a functioning democracy, citizens must start understanding and grappling with these pressing issues in global change.

Climate change gets the lion's share of media attention, but it is not the most certain, not the least reversible, and not the most significant (to date) of human-caused changes to the earth system. This talk , given by Stanford professor Dr. Peter Vitousek, examines the major components of human effects on Earth, with emphasis on the changing composition of the atmosphere, the transformation of Earth's surface by human activity, and the loss of biological diversity.

Computer models are currently relied upon to provide estimates of possible future changes in the Earth's climate. Results from these models were at the center of the global warming debate at the recent Earth Summit in Brazil. There was a great deal of controversy about whether modeling can yield insights into the planet's future. In this talk, Dr. Warren Washington, researcher at the National Center for Atmospheric Research, comments on the climate research community's views and the skeptical response.