  Global characteristics of the small-scale gravity wave (GW) field in the
Martian atmosphere obtained from a high-resolution general circulation model
(GCM) are presented for the first time. The simulated GW-induced temperature
variances are in a good agreement with available radio occultation data in the
lower atmosphere between 10 and 30 km. The model reveals a latitudinal
asymmetry with stronger wave generation in the winter hemisphere, and two
distinctive sources of GWs: mountainous regions and the meandering winter polar
jet. Orographic GWs are filtered while propagating upward, and the mesosphere
is primarily dominated by harmonics with faster horizontal phase velocities.
Wave fluxes are directed mainly against the local wind. GW dissipation in the
upper mesosphere generates body forces of tens of m~s$^{-1}$~sol$^{-1}$, which
tend to close the simulated jets. The results represent a realistic surrogate
for missing observations, which can be used for constraining GW
parameterizations and validating GCM simulations.
