According to the National Academy of Sciences, the surface temperature of the Earth has risen by about a degree in the last 100 years. Many scientists argue that most of the warming over the last 50 years is due to human activity. Others say we don't have enough data to draw that conclusion. This morning on Focus, we're joined by Stanford biologist Stephen Schneider to explore the question of whether climate change is too uncertain for policy.
Many researchers believe that fuel cells will be the power sources of the future. They are more efficient than the internal combustion engine, have no moving parts, and produce almost no pollution. One day they may power our vehicles, our offices, and even our homes. This morning on Focus we're joined by Scott Barnett from Northwestern University to explore the basics of the fuel cell: how it works and some of its potential applications.