  Thermal tides in the Martian atmosphere are analyzed using temperature
profiles retrieved from nadir observations obtained by the TIRVIM
Fourier-spectrometer, part of the Atmospheric Chemistry Suite (ACS) onboard the
ExoMars Trace Gas Orbiter (TGO). The data is selected near the northern summer
solstice at solar longitude (LS) 75{\deg}-105{\deg} of Martian Year (MY) 35.
The observations have a full local time coverage, which enables analyses of
daily temperature anomalies. The observed zonal mean temperature is lower by
4-6K at ~100Pa, but higher towards the summer pole, compared to the LMD Mars
General Circulation Model (GCM). Wave mode decomposition shows dominant diurnal
tide and important semi-diurnal tide and diurnal Kelvin wave, with maximal
amplitudes of 5K, 3K, and 2.5K, respectively, from tens to hundreds of Pa. The
results generally agree well with the LMD Mars GCM, but with noticeable earlier
phases of diurnal (~1h) and semi-diurnal (~3h) tides.
