Seasonal Variation of Martian Surface Temperature over Gale Crater and Surroundings

Abstract Temperature plays an inevitable role in molding the Martian surface. Analysis of the seasonal variation of evening temperature over Gale Crater and its surroundings from Martian years MY 12 to MY 35 (equivalent Earth years 1976–2020) was carried out using data from different orbiter missions such as InfraRed Thermal Mapper (IRTM) data from Viking Orbiter Mission, Thermal emission spectrometer (TES), data from Mars Global Surveyor (MGS) and Thermal Emission Imaging System (THEMIS) data from Mars Odyssey Mission. Bands corresponding to 20 µm for IRTM data, 15 µm for TES data and 9 µm for THEMIS data were used for determination of surface temperature and diurnal temperature variation was estimated from 4 to 6 am and 4 to 6 pm images. It was observed that summer season had the highest evening temperature of about 269 K from MY 12 to MY 35. It was further observed that autumn and winter seasons had low temperature varying between 184 to 256 K and 189 to 272 K respectively for these two seasons whereas spring and summer exhibited high temperature ranging between 190 to 282 K and 223 to 283 K respectively for these two seasons. From the analysis of temperature at different Ls during the three different years MY 12, MY 24 and MY 32, it was noted that the temperature graph followed almost similar pattern. In all these 3 years, there was a hike in the temperature after Ls 150°. Due to global dust storm activity in MY 12 and MY 25 during spring equinox, a sudden increase in temperature was observed. Diurnal temperature variation was found out from these pre-dawn and dusk temperatures. Autumn fall and summer season showed the highest diurnal temperature variation. Significant drops in surface temperature too were observed during MY 26 (more than 30 K from MY 25) and MY 32 (more than 45 K from MY 31) on an average considering all the seasons. Correlation of drop in surface temperature with the surface pressure was confirmed from Mars Science Laboratory (MSL) Rover Environmental Monitoring Station (REMS) data. The THEMIS derived surface temperature accurately correlated with REMS derived surface temperature of MAPE (Mean Absolute Percentage Error) about 4.1%.