Diurnally varying structure of stationary waves encircling the summer southern pole of Mars observed by MGS TES

Abstract

The diurnal variation in the vertical structure of the wavenumber-1 stationary planetary wave observed in the summer southern polar region of Mars was investigated by using temperature data on the dayside and nightside taken by Thermal Emission Spectrometer onboard Mars Global Surveyor. It was found that the westward phase tilt with height during this period tends to be obvious on the dayside, while it is much less on the nightside. A possible explanation for the diurnally-varying wave structure is the advection of wave fields by the tidal wind: the wave fields away from the ground surface are carried westward by the tidal wind during the local time from midnight to noon, and the process is reversed from noon to midnight. The slow vertical propagation of the wave with a time constant much longer than a sol will allow the tidal wind to influence the wave structure. Copyright 2007 by the American Geophysical Union.