High-altitude gravity waves in the Martian thermosphere observed by MAVEN/NGIMS and modeled by a gravity wave scheme

TL;DR

This study presents the first high-altitude observations of gravity wave-induced CO₂ density perturbations in the Martian thermosphere, combining MAVEN/NGIMS data with a gravity wave model to understand their propagation and effects.

Contribution

It provides the first observational evidence of gravity waves at high altitudes on Mars and uses an extended gravity wave scheme with the Mars Climate Database for interpretation.

Findings

Observed density perturbations of 20-40% between 180-220 km

Gravity waves can propagate from lower atmosphere to thermosphere

Modeled effects are qualitatively consistent with observations

Abstract

First high-altitude observations of gravity wave (GW)-induced CO$_2$ density perturbations in the Martian thermosphere retrieved from NASA's NGIMS instrument on board the MAVEN satellite are presented and interpreted using the extended GW parameterization of Yi\u{g}it et al. [2008] and the Mars Climate Database as an input. Observed relative density perturbations between 180-220 km of 20-40 % demonstrate appreciable local time, latitude, and altitude variations. Modeling for the spatiotemporal conditions of the MAVEN observations suggests that GWs can directly propagate from the lower atmosphere to the thermosphere, produce appreciable dynamical effects, and likely contribute to the observed fluctuations. Modeled effects are somewhat smaller than the observed but their highly variable nature is in qualitative agreement with observations. Possible reasons for discrepancies between modeling and measurements are discussed.