Lightning Creates Surprising Chemicals – Spectrum of Science

If scientists have what it takes to become Hollywood stars, then the pilots at NASA’s DC-8 Earth Science Laboratory have to. In the early summer of 2012, they were targeting thunderstorms over the broad plains of central America—the heavier the storm, the better. On board every flight: chemists and their analysis equipment. They were part of the major American collaborative campaign “Deep Convective Clouds and Chemistry” and investigated how thunderstorms change the chemistry of the atmosphere. The researchers compared the composition of the air entering a thunderstorm with that leaving it. They wanted to understand how strong convection currents and lightning affect the chemical composition of the atmosphere. They expected revealing results that would be important to better understand urban air pollution or the formation of greenhouse gases.

“The pilots were fantastic,” recalls William Brune, an atmospheric chemist at Pennsylvania State University. As one of the scientific directors of the campaign, he sat in the cockpit on many flights and decided which thunderstorm to follow. Monitoring their radar, the pilots circled the center of the storm, flying up to the cloud anvil—the top of the storm clouds. “You can’t fly too close, but you have to get as close as possible to see as much of what’s rising out of the storm,” says Brune. “Flying around these storms and into the cloud anvils was spectacular.”

See also  Dogs: Why small animals are more aggressive - Knowledge

The data collected proved to be just as spectacular. During several flights, the team discovered astoundingly high hydroxyl concentrations near thunderstorms, orders of magnitude higher than any previous atmospheric measurements of the reactive radical. Hydroxyl radicals are the primary oxidant of the earth’s atmosphere. They are crucial to the air’s ability to clean itself. A decade after the last flight of the field campaign, the latest findings by Brune and his colleagues on the high hydroxyl spikes now suggest that lightning affects the chemistry of the atmosphere much more than previously thought…

See more here

Leave a Reply

Your email address will not be published. Required fields are marked *