2026/07/01 by Francisco Brasil, Pedro Machado, Gabriella Gilli +7 · 1 voice
Agricultural and Biological Sciences · Physics and Astronomy · #Astro and Planetary Science #Biocrusts and Microbial Ecology #Planetary Science and Exploration
paper · doi:10.1029/2025je009621
openalex publication_date 2026/07/01 · openalex created_date 2026/07/11 · openalex updated_date 2026/07/22
Abstract We present a systematic detection and characterization of mesoscale atmospheric gravity waves in Martian clouds using High Resolution Stereo Camera (HRSC) imagery from Mars Express during Martian Years 34–37. Gravity wave packets were identified in the HRSC Cloud Atlas data set, and their morphology (horizontal wavelength, packet width/length, orientation) was measured on map‐projected products. Cloud top altitudes were derived from blue‐green parallax using HRSC's multi‐channel imaging geometry. For a subset of stereo–temporal “brooming” pairs separated by min, horizontal winds were derived by manual feature tracking, enabling direct estimates of observed and intrinsic phase speeds and implied vertical wavelengths at the packet scale. We cataloged 146 packets, of which 114 were morphologically characterized, measured 100 cloud top heights, and 11 had full dynamical characterization. Horizontal wavelengths span 2–117 km with an average of 29 km. Cloud tops show a dominant concentration between ≈15 and 40 km, and a less frequent extension to 60–100 km, with uncertainty ∼3–10 km, and clear spatial and seasonal variability. For the dynamical subset, observed phase speeds are 2.0–8.6 m/s, intrinsic phase speeds are 0.4–6.2 m/s, and implied vertical wavelengths are 0.2–3.4 km. These results demonstrate that HRSC repeat‐track imaging enables packet‐scale constraints on intrinsic gravity wave drag and mesoscale dynamics in Martian circulation models.