Measurement flights on the formation of ozone by thunderstorms
Thunderstorms have a significant effect on the formation of ozone. Nitrogen oxide is produced as a result of lightning; this in turn yields ozone at altitudes of 10 kilometres. Strong updraughts in thunderstorms also transport emissions from the ground into the upper atmosphere. But how significant is this effect – compared to aviation, for example? Researchers of the DLR Institute of Atmospheric Physics, in collaboration with the US National Center for Atmospheric Research (NCAR), NASA and other partners, are studying such questions. To this end, they will be conducting measurement flights in the United States until mid-June. The researchers are looking to increase the existing body of data and gain a better understanding of the processes that take place in thunderstorms.
The measurements are used to increase the existing data pool. Previous measurements lead to the conclusion that global aviation produces about one teragram of nitrogen oxide per year, but thunderstorms are responsible for about five times as much. All nitrogen oxide sources jointly contribute about 50 teragrams of nitrogen oxide to the atmosphere each year, so thunderstorms are responsible for about 10 percent. New model simulations show that thunderstorms exert a great influence on ozone. Three research aircraft are being used for the mission: the DLR Falcon research aircraft will take measurements at an altitude of 10 kilometres, while the American HIAPER research aircraft will take measurements at up to 15 kilometres. A DC-8, a much larger aircraft, will mainly operate at lower altitudes.
Contact:
Dr. Heidi Huntrieser
Institute of Atmospheric Physics
Atmospheric Trace Species
Telephone: +498153-282514
Telefax: +498153-1841
E-mail: Heidi.Huntrieser@dlr.de