Turbulence in the Lower Atmosphere of Mars Enhanced by Transported Dust Particles

A recent article by Wu et al. (2021, https://doi.org/10.1029/2020JE006752) reports unprecedented turbulence-resolving numerical simulations for Mars, in which the radiative impact of suspended dust particles transported in convective circulations is resolved for the first time. Those simulations demonstrate that in certain conditions, a dustier Martian atmosphere may result in stronger turbulence and mixing in Mars' planetary boundary layer, as a result of the inhomogeneity in the distribution of dust particles being reinforced by turbulent convective cells. This effect competes with what was hitherto thought to dominate in a dustier atmosphere, that is, a turbulence weakening related to surface shading by suspended dust particles. Wu et al. (2021 https://doi.org/10.1029/2020JE006752)'s work has many implications for future studies of Mars' meteorology and climatology. Plain Language Summary Near the surface of Mars, the air is strongly turbulent in daytime as a result of the warm surface heated by sunlight. Before Wu et al. (2021, https://doi. org/10.1029/2020JE006752)'s study, more dust in Mars' air was thought to lead to weaker turbulence because the added dust particles shade the surface. On the contrary, using unprecedented computer simulations calculating the turbulent motions of Martian near-surface air and of the dust particles it carries, Wu et al. (2021, https://doi.org/10.1029/2020JE006752) showed that more dust in Mars' air could lead to stronger turbulence because dust particles locally warm the upward turbulent plumes in which they concentrate. This new result changes the way scientists may view Mars' weather and climate in the future.

Automated summary

The recent study by Wu et al. reveals a new mechanism in which more dust in Mars' atmosphere may lead to stronger turbulence and mixing in the planetary boundary layer. This finding changes scientists' understanding of Mars' weather and climate.