A study of daytime convective vortices and turbulence in the martian Planetary Boundary Layer based on half-a-year of InSight atmospheric measurements and Large-Eddy Simulations

Studying the atmospheric Planetary Boundary Layer (PBL) is crucial to understand the climate of a planet. The meteorological measurements by the instruments onboard InSight make a uniquely rich dataset to study the active turbulent dynamics of the daytime PBL on Mars. Here we use the high-sensitivity continuous pressure, wind, temperature measurements in the first 400 sols of InSight operations to analyze convective gusts, cells, and vortices in Mars' daytime PBL. We compare the InSight measurements to turbulence-resolving Large-Eddy Simulations (LES). The daytime PBL turbulence at the InSight landing site is found to be very active, with clearly identified signatures of convective cells and a vast population of almost 10,000 recorded vortex encounters, adequately represented by a power-law with a 3.5 exponent in agreement with LES results. While the daily variability of vortex encounters at the InSight landing site can be explained by the statistical nature of turbulence, the seasonal variability is strongly correlated with ambient wind speed, which is supported by LES. However, wind gustiness is more correlated to surface temperature than ambient wind speed, confirming the radiative control of the daytime martian PBL; and fewer convective vortices are forming in LES when the background wind is doubled. Thus, the long-term seasonal variability of vortex encounters at the InSight landing site is mainly controlled by the advection of convective vortices by the ambient wind speed. Typical tracks followed by vortices forming in the LES show a similar distribution in direction and length as orbital imagery of the InSight region.