Ion convection and the formation of the mid‐latitude F region ionization trough

摘要: Measurements of total ion concentration and drift velocity from Atmosphere Exlorer C have been used to examine the convective flow plasma in vicinity mid-latitude F region ionization trough. It is found that low-latitude portion premidnight trough a slow eastward drfit while poleward characterized by generally westward flow. The reversal typically occurs on edge where N/sub 1/ observed vary smoothly. We propose flux tubes within corotated into evening local time sector dusk before stagnating flowing at higher latitudes nighttime sector. In absence sources, rather deep troughs can be formed recombination during long required for stagnate reverse. proposed paths result quite naturally combined effects corotation magnetospheric electric fields. Large convection velocities act increase decay rate are not produce but may cause composition changes occasionally themore » trough.« less