During a magnetic storm, energy can be transferred from high to low latitudes in the thermosphere by two dynamical processes: gravity waves and meridional circulation. This paper evaluates the relative importance of these two mechanisms with the aid of a numerical simulation. The appropriate auroral region conditions to be used as input parameters for such a simulation are a matter of considerable uncertainty, but even when these are chosen so as to be relatively favorable to gravity wave energy transfer, meridional circulation is found to be more important in heating the low-latitude thermosphere. |