The characteristics of traveling planetary waves in the troposphere and mesosphere on Mars

Using the temperature provided by the Mars Global Circulation Model (MGCM) reanalysis data from Mars Year 30-32, we investigate the global characteristics of eastward traveling planetary waves (TPWs) with different periods in the Martian atmosphere. Based on the wavenumbers and frequencies, the TPWs in the Martian atmosphere are mainly divided into three modes: quasi-3-sol waves with eastward wavenumber 2, quasi-6.5-sol waves with eastward wavenumber 1, and quasi-20-sol waves with eastward wavenumber 1. The temporal, latitudinal, and altitudinal distributions of TPWs are revealed. The amplitudes of these TPWs are all stronger in the Northern Hemisphere than those in the Southern Hemisphere and are annually enhanced during autumn and winter. Quasi-3-sol waves are strongest in the lower troposphere from 40 degrees N to 70 degrees N. Quasi-6.5-sol waves dominate in the upper troposphere at the latitude from 55 degrees N to 80 degrees N. Quasi-20-sol waves exhibit a double-peak structure in the upper troposphere and the mesosphere from 55 degrees N to 82.5 degrees N in autumn. Additionally, the features of solsticial pause are observed in the quasi-3-sol waves at the surface, in the quasi-6.5-sol waves from the surface to the middle troposphere, and in the quasi-20-sol waves in the lower troposphere. Our analysis suggests that the appearance of the solsticial pause is mainly related to the lack of strong wave sinks or wave sources during the winter solstice.