For centuries, human efforts to protect cities against natural disasters such as earthquakes, storms, floods, epidemic diseases and other natural extremes has been remarkably successful. However, there is recent evidence to suggest an increased vulnerability of urban populations to natural disasters. In this lecture, Rutgers University geography professor James Mitchell makes the case that urban centers are more at risk to natural disaster than commonly thought. While Mitchell acknowledges the progress of cities in preventing and responding to natural hazards, such as floods, he insists that urban planners must be more conscious of the significant risks to urban populations that are still persistent.

"Geoengineering" - ways of mitigating the effects of greenhouse gas emissions, as opposed to reducing those emissions - was proposed by Gregory Benford as a planetary scale solution. Geoengineering options range from the simple to the complex. Benford also discussed the assets and liabilities of these global scale engineering projects.