Quasi-Biennial Oscillation absent in Mars atmospheric reanalysis datasets

Mars’s atmosphere shares many of the same types of oscillations exhibited in Earth’s climate, like the Semiannual Oscillation and Annular Modes, but using two Martian reanalysis datasets derived from Mars Climate Sounder observations, we find that Mars fails to generate a Quasi-Biennial Oscillation (QBO). The lack of a QBO may stem from the absence of a stratosphere on Mars — as the background flow is critical for setting the altitude that vertically propagating waves deposit momentum — or the extreme latitudinal variation of the overturning circulation disrupts waves sources. The lack of a QBO on Mars may enable unique comparisons between Earth’s and Mars’s atmospheres.