2025/12/01 by Charissa Campbell, Scott D. Guzewich, J. Michael Battalio +2 · 1 voice
Physics and Astronomy · Agricultural and Biological Sciences · #Planetary Science and Exploration #Biocrusts and Microbial Ecology #Astro and Planetary Science
paper · doi:10.1029/2025je009268
Abstract Dust storms near Mars' South Pole during the perihelion and summer solstice seasons ( L s ∼ 250–290°) are phenomenologically distinct from martian dust storms in other locations and seasons. While they have previously been observed to increase atmospheric dust loading and warm the south polar atmosphere, they have no notable impact on the middle latitudes, tropics, or northern hemisphere. Here, we use a combination of multiple remote sensing instruments, atmosphere reanalyses, and general circulation modeling to study the evolution of dust storms near the Martian South Pole during Mars Year 30 (a prototypical year for such storms). Dust lifting preferentially occurs in the eastern hemisphere (180°–320°E) and follows the retreating seasonal CO 2 polar cap to higher latitudes as the season progresses—implicating the strong cap edge thermal forcing and katabatic flows as well as surface dust availability in driving dust lifting. Dust remains confined to the high southern latitudes during this season with strong diurnal variability in both latitudinal and vertical extents. Dust is entrained in the southern circumpolar jet stream, creating filamentation and longitudinal mixing and controlling the flow of dust back onto the polar cap. The diurnally varying atmospheric circulation limits the mixing of dust to lower latitudes and prevents a global thermal response.