EMIRS observations of temperature and dust aerosols: Seasonal and diurnal variability

Recently, Emirates Mars Mission (EMM) arrived at Mars on 9 February 2021. It carried three instruments: (1) Emirates eXploration Imager (EXI), (2) Emirates Mars Infrared Spectrometer (EMIRS), and (3) Emirates Mars Ultraviolet Spectrometer (EMUS). In this paper we have used EMIRS data. The EMIRS instrument is measuring atmospheric temperature (at 0.5 mbar) and the column abundance of dust aerosols (referenced to 9 μm), water ice clouds (referenced to 12 μm), and water vapour (pr-μm). These observations were taken between 24 May, 2021 (MY 36, Ls= ~ 50^o) and 24 February, 2022 (MY36, Ls = 180^o). There is a gap in these data between Ls = 100^o and 120^o due to the solar conjunction and the spacecraft entering into safe mode. We have studied the seasonal and diurnal variability of surface temperature and dust aerosols in the Martian atmosphere. These observations are reported at Ls= 5^o interval and 2^o interval in latitude. The data are averaged over longitude. Our results show that Mars was relatively cool with little dust. The growth and decay of regional dust storms were observed by EMIRS instrument. Based on our analysis we conclude that EMIRS instrument is well suited for the study of temporal and seasonal variability of atmospheric temperature and column integrated quantities of dust. Detailed analysis of these observations will improve our understanding of the underlying physical processes. It will also help to validate and tune GCM models. The EMIRS observations are always providing an exciting new information as we enter the dust perihelion season.