A Comparative Study of Daytime Thermally Induced Upslope Flow on Mars and Earth

Abstract

Several characteristics of thermally induced mesoscale upslope flow on Mars and its comparison with that on Earth were investigated using both analytical and numerical model approaches. The conclusions obtained from the analytical and the numerical evaluations for Mars are generally in agreement. The main conclusions are (i) the intensity of the Martian summer daytime upslope flow, with a moderate slope, reaches nearly 10 m s?1 and its depth is about 5 km; (ii) the longwave radiation flux divergence heating, within the lower boundary layer of Mars, has a nonnegligible contribution to the intensity of the upslope flows; and (iii) on Mars, the values of upslope wind speed are, typically, about 2.5 times larger than on Earth under similar conditions. The depth of the daytime upslope flow and the air temperature increase near the surface are 3 to 4 times larger. The vertical eddy exchange coefficient for heat and momentum is about 10 times larger on Mars.