Changes in Thermospheric Neutral and Ionic Species Densities during Global (2018) and Regional (2016) Scale Martian Dust Storms

The effects of Martian dust storms are not only limited to lower atmospheric regime, but the increased dust storm activity could also affect the vertical structure of the constituents in the thermosphere. To this end, this paper investigates the changes in the vertical mixing of neutral and ionic species densities in the thermosphere before and during a regional (2016) and a global (2018) dust storm event; using Neutral Gas and Ion Mass Spectrometer (NGIMS)/ Mars Atmosphere and Volatile Evolution (MAVEN) observations. Care has been taken to keep a restricted solar zenith angle variation (25º) to avoid the effects of changes in solar illumination on the distribution of thermospheric species densities. Contrasting differences in the vertical distribution of neutral (CO 2 , CO, O, N 2 , Ar, He) and ionic (CO 2 + , O + , O 2 + , N 2 + , CO + , Ar + ) atmospheric species before and during the regional and global dust storm events are noticed.