Investigation of Planetary Scale Atmospheric Dynamics Through Analysis of Data From Mars Global Surveyor

Grant #: NNX08AL24G
Senior Scientist: David Hinson

An investigation through analysis of radio occultation data from Mars Global Surveyor (MGS). This study applies analysis tools developed in previous investigations to characterize the behavior of transient eddies and stationary Rossby wayes in both the northern and southern hemispheres. We examine key aspects of eddy behavior, including the abrupt mode transitions, the near-surface meridional winds, the intensification of eddy activity within longitude bands called "storm zones," and the remarkable influence of northern baroclinic eddies on the dust loading of the Martian atmosphere. We identify seasonal patterns of behavior that repeat from year to year and investigate the character and significance of interannual variations. These steps of data analysis are supplemented with numerical simulations by a Mars General Circulation Model (MGCMI first testing the performance of the MGCM against the data and then using the validated simulation to further interpret the observations. In addition, we analyze occultation measurements of geopotential height to determine whether any resonant enhancement of the diurnal, wave-l Kelvin wave occurs near northern summer solstice, and we will use the results to develop improved MGCM simulations of its seasonal evolution. This investigation will contribute to a more continuous and complete climatological record by bridging the sizable gap between atmospheric observations by the MGS Thermal Emission Spectrometer and the Mars Climate Sounder onboard the Mars Reconnaissance Orbiter. The results of this investigation help reduce the uncertainties faced during aerobraking and aerocapture on future missions to Mars. The investigation contributes to an improved understanding of the current climate, which serves as a baseline for studies of past and future climate.