3. Results: Dust-Free Case   a. Diurnal Changes of Horizontal Mean Fields
3.a.i. Turbulent diffusion coefficient Figure 3b: Vertical profiles of horizontal mean turbulent diffusion coefficient below 1 km for the dust-free case. Profiles are from 8:00 to 18:00 LT every 2 hours on day 6. The number on each line denotes local time. Figure 3b shows the diurnal change of the horizontal mean turbulent diffusion coefficient below 1 km. Below 150 m, the horizontal mean turbulent diffusion coefficient decreases toward the ground surface. From 12:00 to 14:00 LT, when thermal convection activity is largest, the horizontal mean turbulent diffusion coefficient is approximately 20 m2 sec-1 except near the surface.
A numerical simulation of thermal convection in the Martian lower atmosphere with a two-dimensional anelastic model