IPA scientists observe less nitrogen oxides in tropical thunderstorms than expected
Hans Schlager
Thunderstorms are not only spectacular weather events. They also have a great influence on atmospheric chemistry and climate. In a lightning channel, substantial amounts of nitrogen oxides (NO) are formed from nitrogen and oxygen. However, it was still an open question how much nitrogen oxide is generated. Researchers of the DLR Institute of Atmospheric Physics (IPA) now achieved a surprising result: tropical thunderstorms produce less nitrogen oxides than expected.
In the last years severe tropical thunderstorms have been investigated during numerous missions with research aircraft and lightning detection systems on four continents. These missions resulted in fundamentally new and unexpected findings about the processes in extreme thunderstorm clouds. Although the number of flashes in tropical thunderstorms is very high, the flashes do not produce the expected amount of nitrogen oxides. Detailed investigations revealed that not only the number of lightning flashes is of importance, but also their length: tropical thunderstorms produce especially short flashes. The recently published results of the IPA scientists were meanwhile also confirmed by NASA scientists.