Transient luminous events, such as red sprites, occur in the middle atmosphere in the electric field above thunderstorms. We here address the question whether these processes may be a significant source of odd nitrogen and affect ozone or other important trace species. A well-established coupled ion-neutral chemical model has been extended for this purpose and applied together with estimated rates of ionisation, excitation and dissociation based on spectroscopic ratios from ISUAL on FORMOSAT-2. This approach is used to estimate the NOx and ozone changes for two type cases. The NOx enhancements are at most one order of magnitude in the streamers, which means a production of at most 10 mol per event, or ( given a global rate of occurrence of three events per minute) some 150-1500 kg per day. The present study therefore indicates that sprites are insignificant as a global source of NOx. Local effects on ozone are also negligible, but the local enhancement of NOx may be significant, up to 5 times the minimum background at 70 km in extraordinary cases.
Bibliographical noteThe article and any associated published material is distributed under the Creative Commons Attribution 3.0.
- meteorology and atmospheric dynamics
- atmospheric composition and structure
- composition and chemistry
- atmospheric electricity
- middle atmosphere
Enell, C. F., Arnone, E., Adachi, T., Chanrion, O. A., Verronen, P. T., Seppala, A., Neubert, T., Ulich, T., Turunen, E., Takahashi, Y., & Hsu, R. R. (2008). Parameterisation of the chemical effects of sprites in the middle atmosphere. Annales Geophysicae, 26(1), 13-27. https://doi.org/10.5194/angeo-26-13-2008