Gravity waves and high-altitude CO$_2$ ice cloud formation in the Martian atmosphere

TL;DR

This study uses advanced climate modeling to demonstrate that gravity waves significantly influence high-altitude CO2 ice cloud formation on Mars, aligning well with observations and predicting clouds at previously unobserved higher altitudes.

Contribution

First general circulation model simulations quantifying gravity wave effects on Martian CO2 cloud formation, including their tidal modulation and higher altitude predictions.

Findings

Gravity waves induce temperature fluctuations conducive to CO2 cloud formation.

Model results align with observed high-altitude CO2 ice clouds.

Predicted clouds at higher altitudes than previously observed.

Abstract

We present the first general circulation model simulations that quantify and reproduce patches of extremely cold air required for CO$_2$ condensation and cloud formation in the Martian mesosphere. They are created by subgrid-scale gravity waves (GWs) accounted for in the model with the interactively implemented spectral parameterization. Distributions of GW-induced temperature fluctuations and occurrences of supersaturation conditions are in a good agreement with observations of high-altitude CO$_2$ ice clouds. Our study confirms the key role of GWs in facilitating CO$_2$ cloud formation, discusses their tidal modulation, and predicts clouds at altitudes higher than have been observed to date.