Martian Atmospheric Tides Revealed From MAVEN/IUVS and MRO/MCS Observations.

Utilizing atmospheric temperature observed from Mars Years 33–36 by the imaging ultraviolet spectrograph (IUVS) onboard the Mars atmosphere and volatile evolution (MAVEN) and Mars climate sounder (MCS) onboard Mars Reconnaissance Orbiter (MRO), we derive the diurnal and semidiurnal thermal tides from 30 to 160 km. Vertical phase velocities of the migrating tides indicate their upward propagation above 100 km during the dust season (solar longitude, Ls 240°–300°). During the non‐dust season (Ls 30°–150°), the diurnal eastward wavenumber 2 (DE2) and wavenumber 3 (DE3) tides can propagate upward from the lower atmosphere to ∼140 km. The seasonal variation of DE2 and DE3 amplitudes in the thermosphere corresponds well to their counterparts in the lower atmosphere, primarily controlled by their Hough (1, 1) modes. The upward propagation of these tides could potentially impact the vertical coupling between the Martian lower and upper atmosphere. Plain Language Summary: Atmospheric thermal tides are perturbations caused by the absorption of solar radiation in the atmosphere, a phenomenon in Earth's and other planetary atmospheres. The vertical propagation of tides plays a crucial role in transporting energy and momentum vertically within the atmosphere. Observing atmospheric temperatures at different local times makes it possible to determine various tidal components' amplitude and propagation characteristics. Based on data from different satellites, this study investigates the characteristics of tidal amplitude and propagation on Mars. The migrating tides, which move westward in sync with the sun's motion, can propagate upward in the region above 100 km during the dust season. During the non‐dust season on Mars, the diurnal eastward propagating wavenumber 2 (DE2) and wavenumber 3 (DE3) tide exhibits apparent upward propagation from the atmosphere below 40 km into the thermosphere. As Mars has weaker gravity and a lower exobase altitude than Earth, the vertical propagation of tides may directly transmit energy from lower atmospheric activities to the upper layers of the Martian atmosphere, influencing the atmospheric escape rate. Key Points: The thermal tides are derived from temperature observations by two satellites with different altitude rangesMigrating tides are strong in the mesosphere and thermosphere and can propagate upward from 100 km during the Martian dust seasonDuring the non‐dusty season, the diurnal eastward wavenumber 2 (DE2) and 3 (DE3) tides propagate from the troposphere to the thermosphere [ABSTRACT FROM AUTHOR]