Asymmetric Impacts on Mars’ Polar Vortices From an Equinoctial Global Dust Storm

Mars possesses dynamical features called polar vortices: regions of cold, isolated air over the poles circumscribed by powerful westerly jets which can act as barriers to transport dust, water, and chemical species. The 2018 Global Dust Storm was observed multiple orbiters offered a valuable opportunity study effects such storm on dynamics. To this end, we assimilate data from Climate Sounder Atmospheric Chemistry Suite into Model. We find that had asymmetrical hemispherical impacts, with northern vortex remaining relatively robust while southern substantially diminished in its intensity. propose asymmetry due both storm’s latitudinal extent, it extended further south than north, equinoctial timing, occurring already decaying. show vortices, particular northern, were reduced ellipticity storm. There well-correlated reduction stationary topographic wave activity at high latitudes hemispheres. demonstrate characteristic elliptical Martian shape is pattern waves, suppressed shifting jet away mechanical forcing (north) or intensity meridional temperature gradient (south). These asymmetric suggest increased (but not northern) region during global dust storms autumn equinox, more longitudinally symmetric around poles.