Seasonal variability of dust on Mars: Lessons learned from Earth for dust mass estimation

Abstract

<p>The study of dust transport on Mars is crucial to understanding the dust climatic implications. The dust mass loading is one of the main proxies to evaluate indeed the role of dust on the atmospheric dynamics.</p><p>Earth studies on dust can serve to estimate the dust mass concentration from the opacity observations on Mars. Nine years of Mars Global Surveyor (MGS) data on Martian weather patterns are available. In particular, the Thermal Emission Spectrometer (TES) database with Martian dust opacity observations is used in this work to assess the seasonal dust mass variability.</p><p>First, the space-time variability of the Martian dust opacity is yearly studied using averages in bins of 2° latitude x 5° longitude and 5° aerocentric longitude (Ls). This information allows for estimating the potential planetary dust liftings and depositions. Second, extinction-to-mass conversion factors for dust particles, as obtained from different dust desert regions on Earth (Sahara, Arabian Peninsula, Gobi, …), are applied to Mars dust opacity (i.e., dust extinction) retrievals in order to determine the variability of the dust mass loading during the dust transport on Mars. Third, a seasonal study is performed. Results present an overall dust dynamic scenario in terms of the seasonal dust mass variation across the planet.</p>