Extratropical cyclones, frontal waves, and Mars dust: Modeling and considerations

Abstract

A Mars GCM is utilized to investigate dust lifting and organization associated with extratropical cyclogenesis and frontal waves. The model is applied at high resolution in simulations related to Mars' dust cycle. A single extratropical synoptic weather event is examined to ascertain lifting, transport and convergence/divergence of dust by large-scale cyclonic/anticyclonic weather systems, and the sub-synoptic frontal waves that ensue. Low- and high-pressure cores develop, travel eastward and remain mostly confined within the seasonal CO 2 polar cap. The bulk of dust lifting occurs in the northern-hemisphere western highlands associated with nocturnal down-slope drainage flows, and lifting infrequently occurs near the frontal convergence zone. Dust becomes organized and transported within circulations associated with the synoptic/sub-synoptic circulations accompanying the frontal waves. Dynamical considerations are invoked regarding frontogenesis revealing correlations with regards to dust lifting, organization and transport. Implications of large-scale extratropical weather systems on the martian dust cycle are discussed. © 2010 by the American Geophysical Union.