The impact on the ozone layer from NOx produced by terrestrial gamma ray flashes

作者：Cramer E S^*; Briggs M S; Liu N; Mailyan B; Dwyer J R; Rassoul H K

来源：Geophysical Research Letters, 2017, 44(10): 5240-5245.

DOI：10.1002/2017GL073215

The motivation of this work is to understand the effects of terrestrial gamma ray flashes (TGFs) on the ozone layer. One of the main ozone-destroying mechanisms is the production of NOx in the stratospheric region. NOx from lightning has been considered as a possible cause of ozone depletion, but probably little of this NOx is transported from the tropopause to the stratosphere. Since the energetic particles of TGFs travel from approximate to 12 km to space, the resulting ionization can produce NOx directly in the stratosphere. In order to quantify the production of stratospheric NOx from TGFs, we use the Runaway Electron Avalanche Model to simulate a typical setup of the acceleration region inside a thundercloud. The photons are then transported through the Earth's atmosphere, where they deposit some of their energy as ionization in the ozone layer. We then calculate the number of NOx molecules produced by considering the average energy required to produce one electron-ion pair. Finally, the effect of TGF NOx production is estimated using the global annual rate of TGFs. It is estimated that the NOx production of TGFs is completely negligible compared to other sources, and therefore, TGFs have no effect on the ozone layer.
Plain Language Summary This paper addresses radiation emitted from thunderstorms and the impact on the ozone layer. Air pollution in the form of Nitrogen oxides (NOx) can harm the ozone layer which protects the surface of the Earth from harmful radiation. We address the production of NOx from the radiation associated with lightning and evaluate the negative contribution that it has on the ozone layer.

• 出版日期2017-5-28