Modeling Thermal Tides in the Martian Atmosphere with the Mars Planetary Climate Model (PCM)

Modeling thermal tides in the Martian atmosphere has been a long-standing challenge, which is also one of the current bottlenecks in understanding the climate of Mars. Driven by the diurnal solar forcing and influenced by the planetary topography, thermal tides play important roles in the Martian atmosphere and dominate the diurnal variations. Observations obtained by the TIRVIM Fourier-spectrometer, part of the Atmospheric Chemistry Suite (ACS) onboard the ExoMars Trace Gas Orbiter (TGO) and the Emirates Mars InfraRed Spectrometer (EMIRS) onboard the Emirates Mars Mission (EMM) Hope spacecraft show noticeable disagreements with model predictions that the observed diurnal tide usually has earlier phase and semi-diurnal tide has longer vertical wavelength. In this talk, we present a modeling study of thermal tides in the Martian atmosphere using the Mars Planetary Climate Model (PCM), previously known as the Laboratoire de Météorologie Dynamique Mars Global Circulation Model (LMD Mars GCM). A series of scenarios with different dust loading, physical processes of dust transport and cloud formation, non-orographic gravity waves and varying atmospheric heat capacity are tested. Validation of this work provides valuable information on understanding physical processes in the Martian atmosphere on a diurnal scale and inspires further advances of Mars GCMs.