Seasonality of aeolian landforms on Meridiani Planum, Mars

The wind interacts with the surface of Mars, forming aeolian landforms. The orientation of these landforms informs us about the formative wind directions. The observations of the orientation of aeolian landforms on Meridiani Planum between Mars years 26 and 38 indicated that there is a seasonality of formative wind directions in this region. The studied landforms were shaped by a predominant SE wind during summer, while during winter several wind directions played a role in their formation. Throughout the Mars year, the most formative were the NW winds. The presence of dark wind streaks oriented toward the west during winter indicates that E winds occur in this season on Meridiani Planum, as previously predicted by numerical simulations. It was also found that aeolian deflation led to complete erosion of smaller dunes, and that the relatively strong deflation was responsible for the scarcity of fine-grained ripples on Meridiani Planum. In this region, fine-grained ripples were found only in a few locations, and they were mainly small bedforms with wavelengths up to several centimeters. • In situ and orbital data from a period between Mars years 26 and 38 were analyzed. • There is a seasonality of aeolian landforms on Meridiani Planum. • The most formative winds blow from NW, but in summer SE winds dominate. • Numerically predicted modern E winds occur mainly in winter. • Deflation led to complete erosion of three dome dunes in the studied period.