Impacts of Carbon Dioxide Deposition on Martian Near‐Surface Wave Activity

A prominent feature of Mars' winter atmosphere is near‐surface baroclinic wave activity. These waves exert strong control on dust storm variability and contribute to transport of heat, momentum, and dust. Using a suite of Mars general circulation model simulations, we investigate an underexplored connection between near‐surface wave activity and another distinctive feature of Martian atmosphere: deposition of its primary constituent in winter polar regions. We identify a two‐fold impact: deposition of atmospheric onto the surface extends the duration of high wave activity into spring, while latent heat release during deposition suppresses wave activity during winter. Both effects arise from changes in the westerly jet structure. deposition modifies the spatial and temporal structure of the jet, altering the baroclinic instability growth rate, and hence strength and timing of near‐surface waves. Our study highlights the importance of considering deposition in understanding Martian dust storms and atmospheric transport.