Mars global atmospheric oscillations - Annually synchronized, transient normal-mode oscillations and the triggering of global dust storms

Abstract

Transient events of an unusual character have been discovered in the daily pressure variations of the Mars atmosphere's pressure at the planetary surface which last only a few Martian days, appear to repeat on an annual basis, cover a large part of the given day's hemisphere, occur in pairs separated by 20-days in some cases, and coincide with the annual pressure minimum. They also consist of spectral components nearly identical in frequency with diurnal and semidiurnal harmonics. It is presently suggested that these events are Kelvin, normal-mode, transient, global oscillations. An almost-diurnal and an almost-semidiurnal high-frequency global oscillation distinct from solar-driven tides may be common on Mars.