Hydrogen economy's effects on stratospheric ozone disputed.

• Author: Sawin, Janet L.
• Position: Environmental Intelligence

In July, scientists from NASA, Georgia Tech, the University of Wisconsin, and Hampton University in Virginia announced a notable slowing in the rate of destruction of the ozone layer. While not a reversal of the thinning, the detected change is viewed as a significant turning point in the effort to heal the ozone layer, due to curbs on chlorofluorocarbon (CFC) emissions.

These findings heightened the significance of a study recently released in Science, which found evidence that the leakage of hydrogen gas during production, storage, and distribution could moisten and thus cool Earth's stratosphere, making the ozone hole larger, deeper, and more persistent. The study, conducted by scientists at the California Institute of Technology (CalTech) and the Jet Propulsion Laboratory (JPL), suggested that recovery of the ozone layer could be delayed considerably, depending on how soon a hydrogen economy develops. It also revealed additional potential impacts of increased hydrogen emissions, including their potential to affect lifetimes of various gases in the stratosphere, including some greenhouse gases. If such findings were to prove true, the development of a hydrogen-based economy, purported to be the answer to a host of concerns ranging from energy security to global warming, could in itself pose a serious threat to some of...