Abstract Records of meteor drifts obtained during the I.Q.S.Y. with the radio-meteor technique have been used to resolve wind shears in the 80–100-km region of the upper atmosphere. Some theoretical aspects relevant to the technique of observation are being dealt with and comparison is made with wind shear data obtained by different methods. Two main shear generating mechanisms, turbulence and internal gravity waves, are taken into consideration and it is shown that the present results are more in keeping with a regular wave structure of the upper atmosphere.