Spectral Analysis of the Martian Atmospheric Turbulence: InSight Observations. Issue 15 (5th August 2022)

• Record Type: Journal Article
• Authors: Temel, Orkun; Senel, Cem Berk; Spiga, Aymeric; Murdoch, Naomi; Banfield, Don; Karatekin, Ozgur
• Is Part Of: Geophysical research letters. Volume 49:Issue 15(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-05
• Subjects: Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2022GL099388
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: In this study, we perform spectral analysis of Martian near‐surface turbulence using the in‐situ observations by NASA's InSight lander on Mars. A recent study on the daytime Martian boundary layer using the InSight observations showed that the conventional Kolmogorov energy cascade of inertial subrange fails to predict the spectral density of pressure (Banfield et al., 2020, https://doi.org/10.1038/s41561-020-0544-y ). Here we extend this by investigating diurnal and seasonal variations in the spectral density of pressure, as the indicator of the Martian atmospheric turbulence. We show distinct spectral behaviors for the daytime and nighttime conditions. Moreover, we report the important effects of regional dust storms, gravity waves (GWs), bore, and solitary waves on the turbulent energy cascade. Our results show that the presence of a dust storm and GW activity can enhance the turbulence of the nighttime boundary layer of Mars despite the extreme stably stratified conditions compared to the terrestrial case. Plain Language Summary: Turbulent mixing in the first kilometers above the planetary surface, the atmospheric boundary layer, drives the transport of momentum, heat, and volatiles between a planet's surface and its atmosphere. Thus, it requires a detailed investigation by observations to be able to understand better the atmospheric dynamics, and most importantly, the processes controlling them. In this study, we make use of the InSight lander's pressure observations to understand how the Martian atmospheric turbulence differs over a daily cycle and in different seasons. Here we showed that the nocturnal near‐surface environment of Mars can be more turbulent than thought before and it can have important implications for the Martian atmospheric seasonal cycles. We also find that the daytime and nocturnal turbulence exhibits different behaviors, which are affected by the presence of a regional dust storm and gravity wave activity. Key Points: We make use of in‐situ observations to investigate the Martian atmospheric turbulence We find distinct spectral behaviors of turbulence for daytime and nighttime conditions We report important effects of a regional dust storm and gravity wave activity on the turbulence energy cascade