SA005-0017
The effect of large meteoroid impacts on the ozone and nitric oxide budget in the Earth’s upper atmosphere
Abstract:
1Department of Cybernetics and Artificial Intelligence, Faculty of Electrical Engineering and Informatics, Technical University of Kosice, Kosice, Slovakia
2Department of Earth Sciences, Western University, London, ON, Canada
3Finnish Geospatial Research Institute (FGI), Masala, Finland
4Department of Physics, Helsinki University, Finland
5Institute of Physics and Technology, Ural Federal University, Ekaterinburg, Russia
6Yale University, Geology and Geophysics, New Haven, CT, 06511, United States
Most optically detectable meteors (0 magnitude or brighter) generate shockwaves during the lower transitional flow regimes in the mesosphere-lower thermosphere (MLT) region of the Earth’s atmosphere. Meteor generated shockwaves can modify the surrounding atmosphere and produce a range of physicochemical effects, including removal of ozone (O3) and production of nitric oxide (NO) (Silber et al. 2017; 2018a). It was previously shown that centimeter-sized meteoroids are capable of producing NO in the MLT region (Menees & Park 1976; Park & Menees 1978); however, as per most recent estimates, the total annual contribution is only about 1000 tons (Silber et al. 2018b). We expand on that work to explore the effect of large meteoroids (the Chelyabinsk class) on the surrounding atmosphere during their descent, and evaluate whether there is a detectable (albeit temporary) contribution to the O3 and NO budget. We also contrast the NO production efficiency of large bolides and cm-sized meteoroids. Moreover, we explore long term effects of meteoric species deposition in the upper atmosphere with the focus on the Chelyabinsk class events.
References:
Menees G.P. & Park C. (1976) Atm. Env. 10, 535-545.
Park C. & Menees G.P. (1978) JGR: Oceans. 83, 4029-4035.
Silber E. A. et al. (2018a) Adv. Sp. Res., 62(3), 489-532.
Silber E.A. et al. (2018b) Atmosphere, 9(202), 1-21.