Abstract
Numerical experiments are performed to investigate to what extent the observed features are explained in terms of the dynamical modification of air flow by the realistic Mars topography. The real Mars topography based on radar- and optical observations is incorporated in the fully non-linear shallow water equations with realistic Coriolis parameter. These equations are integrated numerically as an initial and boundary value problem for air flow across mountain.
Comparison of results with the observed data shows the following;
1) In spite of a limitation that the baroclinic effect is ignored, the quasi-stationary troughs and ridges are realized and they are highly in agreement with observed circulation patterns. This result endorses that the observed permanent low or steady flow on Mars appears under the strong influence of orography.
2) The present numerical experiments also suggest that in the northern hemisphere, north winds intensified by orography would be considerably responsible for the courses of “darkening waves”.