Political leaders throughout the world have taken notice of the increasing levels of carbon in the atmosphere and have begun negotiations on how to mitigate “greenhouse” gases through accords such as the Kyoto Protocol. One major problem with the Kyoto Protocol, which the United States rejected, was how to monitor compliance. Currently there is no good way to tell how much carbon is being emitted from – or taken up by – land on a country-sized scale. This makes accords such as the Kyoto Protocol, should they be agreed upon, nearly impossible to enforce. That’s why researchers at Harvard University are developing novel methods to measure greenhouse gases in the atmosphere. The scientists, led by Steven Wofsy, Abbot Lawrence Rotch Professor of Atmospheric and Environmental Science, are using specially equipped airplanes to chase air masses through the atmosphere and measure them. Such measurements are critical to understanding carbon amounts at regional and continental scales. NASA, the Department of Energy, the National Science Foundation, and the National Oceanographic and Atmospheric Administration fund the project.