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arXiv · 1511.00344

A global view of gravity waves in the Martian atmosphere inferred from a high-resolution general circulation model

Takeshi Kuroda·Alexander S. Medvedev·Erdal Yiğit·Paul Hartogh
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Abstract

Global characteristics of the small-scale gravity wave (GW) field in the Martian atmosphere obtained from a high-resolution general circulation model (GCM) are presented for the first time. The simulated GW-induced temperature variances are in a good agreement with available radio occultation data in the lower atmosphere between 10 and 30 km. The model reveals a latitudinal asymmetry with stronger wave generation in the winter hemisphere, and two distinctive sources of GWs: mountainous regions and the meandering winter polar jet. Orographic GWs are filtered while propagating upward, and the mesosphere is primarily dominated by harmonics with faster horizontal phase velocities. Wave fluxes are directed mainly against the local wind. GW dissipation in the upper mesosphere generates body forces of tens of m~s$^{-1}$~sol$^{-1}$, which tend to close the simulated jets. The results represent a realistic surrogate for missing observations, which can be used for constraining GW parameterizations and validating GCM simulations.

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Takeshi Kuroda, Alexander S. Medvedev, Erdal Yiğit, Paul Hartogh. 2015-11-02. A global view of gravity waves in the Martian atmosphere inferred from a high-resolution general circulation model. https://doi.org/10.1002/2015gl066332

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