Winds on Mars during the Viking season: Predictions based on a general circulation model with topography

The Arakawa‐Mintz general circulation model of the Earth has been applied to Mars at the season of the nominal Viking Lander mission. Allowance has been made for the effects of the large Martian topography. The calculated wind fields exhibit significant zonally symmetric, topographically forced, and diurnal tidal components. Average wind speeds of 20‐25 m/sec were found at three possible landing sites, with wind speeds occasionally reaching values as much as a factor of 2 larger than these average values. If buffering by CO 2 adsorbed in the regolith can be neglected, a pressure decline of about 0.8 mb is expected over the first 2 months of operation of the first lander.