Basic Features of Global Circulation in the Mesopause Lower Thermosphere Region

D1 and D2 techniques have been used and are being used for observations at stations located in the high, middle, and low latitudes of both hemispheres. The systematical and wind velocity measurements with these techniques make it possible to specify and to refine earlier mesopause-lower thermosphere circulation models. With this in view, an effort was made to obtain global long term average height-latitude sections of the wind field at 70 to 110 km using the analysis of long period D1 and D2 observations. Data from 26 meteor radar and 6 ionospheric stations were taken for analysis.