Summary
obtained from Davis station in Antarctica (69S, 78E) provide an opportunity to study interhemispheric coupling. Observations and modelling described by Becker and Fritts (Ann. Geophys, 24, 1175-1188, 2006) suggests that wintertime planetary wave activity, and the gravity wave filtering associated with it, affect the global meridional residual circulation that drives the summer mesosphere away from radiative equilibrium. In this context, southern hemisphere stations have the advantage that planetary wave activity in the opposite (NH) hemisphere is of greater magnitude making a response likely. This study uses correlation and superposed epoch analyses, and proposed coupling mechanisms (e.g. Karlsson et al., J. Atmos, Sol-Terr Phys., 71, 518-530,2009] to identify atmospheric regions that are potentially coupled to the polar MLT. Seasonal variations in coupling and the influence on coupling of large-scale circulations, such as the QBO, are discussed.