Characteristics and dynamics of spring-time northern cap-edge dust activities simulated by a Mars climate model

Northern cap-edge dust storms during spring are major dust activities in the non-dusty season of Mars. In this study, we apply a parameterization scheme to the Mars climate model MarsWRF to simulate the dust activities in the northern cap-edge region. Consistent with observations, the simulation result shows a period of weak dust activities in the northern mid spring (Ls 30°-60°) and a stronger period just before the northern summer solstice, with a pause of dust activities between these two periods. The results of the sensitivity experiments suggest that the sublimation flow associated with cap recession is important to the occurrence of dust lifting but its effect on dust lifting near the cap edge could be different in different periods. The sublimation flow generally reduces the dust lifting flux in mid spring while enhances dust lifting at the end of spring. Three specific areas that are prone to dust lifting have also been identified. The simulation results suggest that the locations of the preferred dust lifting areas and the pause between the two active periods are possibly related to the topography in northern high latitudes.