2 satellites have been used to generate an empirical wind model for the upper
thermosphere, analogous to the MSIS model for temperature and density, using a limited set
of vector spherical harmonics. The model is limited to above approximately 220 km where
the data coverage is best and wind variations with height are reduced by viscosity. The data
base is not adequate to detect solar cycle (F10. 7) effects at this time but does include …