Winds at the Mars 2020 Landing Site. 2. Wind Variability and Turbulence.

Area of Science:

• Planetary Science
• Atmospheric Science
• Mars Exploration

Background:

• Mars 2020 Perseverance rover collected wind data in Jezero crater.
• InSight lander data from Elysium Planitia provide comparative context.
• Jezero crater exhibits intense aeolian activity despite calmer average wind speeds.

Purpose of the Study:

• Characterize wind speed distributions and turbulence in Jezero crater.
• Investigate the drivers of aeolian activity on Mars.
• Understand the impact of wind dynamics on rover instrumentation.

Main Methods:

• Fitting wind speed data to a Weibull distribution.
• Analyzing power spectral density of wind speed fluctuations.
• Correlating wind variations with atmospheric phenomena like convection cells and dust storms.

Main Results:

• Jezero winds are calmer on average than at previous Mars landing sites.
• Turbulence and wave activity significantly influence wind speed variations and extreme wind events.
• Convective vortices and mechanical turbulence contribute to rapid wind fluctuations, peaking at 9.2 times background levels.
• A large dust cloud (0.75-1.5 km) was observed passing over the rover.

Conclusions:

• Transient high wind events, driven by vortex passages and turbulence, are key drivers of aeolian activity at Jezero.
• Observed aeolian activity has led to damage to the rover's wind sensor.
• Understanding Martian wind dynamics is crucial for future missions and instrument design.