Seasonal dependence of northern high‐latitude upper thermospheric winds: A quiet time climatological study based on ground‐based and space‐based measurements

摘要: This paper investigates the large-scale seasonal dependence of geomagnetically quiet time, northern high-latitude F region thermospheric winds by combining extensive observations from eight ground-based (optical remote sensing) and three space-based sensing in situ) instruments. To provide a comprehensive picture wind morphology, data are assimilated into empirical vector model as function season, latitude, local time magnetic coordinates. The accurately represents behavior constituent sets. There is good general agreement among various sets, but there some major offsets between GOCE other especially on duskside. patterns exhibit strong large duskside anticyclonic circulation cell, sharp latitudinal gradients auroral zone, antisunward polar cap, weaker tendency toward dawnside cyclonic cell. system shows progressive intensification winter to equinox summer. extent cell does not depend strongly season. Zonal show mainly diurnal variation (two extrema) around middle latitudes semidiurnal (four at latitudes; meridional primarily all high latitudes. strength zonal channeling through zone strongest summer vorticity pattern increases summer, whereas divergence maximum equinox. In seasons, than vorticity.