Geoengineering Earth's Climate

Google Tech Talks January, 7 2008 Emergency preparedness is generally considered to be a good thing, yet there is no plan regarding what we might do should we be faced with a climate emergency. Such an emergency could take the form of a rapid shift in precipitation patterns, a collapse of the great ice sheets, the imminent triggering of strong climate system feedbacks, or perhaps the loss of valuable ecosystems. Over the past decade, we have used climate models to investigate the potential to reverse some of the effects of greenhouse gases in the atmosphere by deflecting some incoming sunlight back to space. This would probably be most cost-effectively achieved with the placement of small particles in or above the stratosphere. Our model simulations indicate that such geoengineering approaches could potentially bring our climate closer to the state is was in prior to the introduction of greenhouse gases. This talk will present much of what is known about such geoengineering approaches, and raise a range of issues likely to stimulate lively discussion. Speaker: Ken Caldeira Ken Caldeira is a scientist at the Carnegie Institution Department of Global Ecology and a Professor (by courtesy) at the Stanford University Department of Environmental and Earth System Sciences. Previously, he worked for 12 years in the Energy and Environment Directorate at the Lawrence Livermore National Laboratory (Department of Energy). His research interests include the numerical simulation of Earth's climate, carbon, and biogeochemistry; ocean acidification; climate emergency response systems; evaluating approaches to supplying environmentally-friendly energy services; ocean carbon sequestration; long-term evolution of climate and geochemical cycles; and marine biogeochemical cycles. Caldeira has a B.A. in Philosophy from Rutgers College and an M.S. and Ph.D. in Atmospheric Sciences from New York University.