With the worlds population growing toward 9 billion--coupled with rising incomes, expanding meat consumption, and increased allocation of cropland for biofuels--the goals of meeting basic food needs, reducing global hunger, and preserving the health of the planet will become ever more challenging. In this public talk, Dr. Rosamond Naylor, fellow at Stanford University's Institute for International Studies, examines this challenge in the context of key countries, food-feed-fuel connections, and increased instability in commodity and financial markets.

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.

Temperature observations during the 20th century reveal a warming trend unlike any other in many millennia. As one of the preeminent scientists looking for an explanation of this phenomena, Princeton University professor V. Ramaswamy provides an overview of existing climate models and explains in an accessible manner how various natural and anthropogenic variables potentially bring about climate change. Through his summary of available research, Ramaswamy argues that human-induced variables, particularly greenhouse gas emissions, appear to be primarily responsible for the warming trend of the 20th century.

This public lecture is taken from a scientific meeting on the topic: "Global Change and Natural Hazards." In this talk, Dr. William Hooke, director of the US Weather Research Program Office at the National Oceanic and Atmospheric Administration, explores extreme events, which include geophysical phenomena, ecosystem events, and societal extreme events. He discusses how the research community and government programs approach this "cycle of disaster."

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.

We are now in an unprecedented age where humans have become a force of global importance and where local human behavior has significant global impacts. In light of this new world order, Dr. Richard Rockwell of the University of Michigan addresses the issue of identifying and mitigating the negative impacts of human activity on the environment. These impacts, which Dr. Rockwell describes as large and growing, are and will continue to affect every individual, regardless of whether they directly contribute to the impacts or not.

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.