Investigating the Morphologies of Local-Scale Dust Storms in the Northern Hemisphere of Mars

Mars is notable for its frequent and intense dust storms. These storms can be found at nearly every location on the planet, though they vary in frequency and intensity. Dust storms on Mars are seasonal, with most storms occurring during northern fall and winter, from L_s~135^o to L_s~360^o. During this season, increased heating associated with perihelion causes intense westerly jets to form around the north polar ice cap with wind speeds frequently greater than 130 m/s. Recent studies have suggested a possible correlation between the curvature and orientation of storms in this region and whether they formed in an entrance or exit region of a jet streak. To evaluate the validity of these claims, we have developed the Mars Storm Orientation and Curvature Quantifier (MSOCQ), a novel computer program which determines the approximate average curvature of dust storms and their orientations based on satellite imagery from Mars Daily Global Maps (MDGMs) produced by the Mars Reconnaissance Orbiter (MRO) Mars Color Imager (MARCI). Our study focuses on storms that are considered to be “local-scale” (<1.6 x 10⁶ km²) centered above ~45^oN from Mars Year (MY) 28 L_s~160^o to MY 28 L_s~195^o and MY 28 L_s~340^o to MY 28 L_s~360^o. We manually classified storms into one of four categories based on their appearance: “puffy”, “pebbled”, “ruffled”, or “plume-like.” Because each of these storm types has different methods of formation and is associated with different convective environments, we expect to observe significant differences in the importance jet streaks play in their formation.