Non-homogeneous structure of neutral winds in the lower thermosphere during the MAC/EPSILON campaign

Abstract

The paper presents the results of an investigation of the height variations of dynamic processes in the 80-110 km height region, carried out in Kazan, U.S.S.R. (56°N, 49°E) by the radiometeor method during the MAC/EPSILON campaign. Experimental results show that the largest values of vertical wind gradients, as well as zonal and meridional temperature gradients can be found at heights of ~ 83 km. At heights of 80 ≤ h ≤ 100 km, we can observe energy absorption of IGW and tides which are the major sources of turbulent energy in the above-mentioned height interval. Using the effects of IGW energy absorption, values of the turbulent eddy diffusion coefficient Kl ranging from 1600 to 4400 m2/s were calculated for October 1987. The energy dissipation rate ε{lunate} was estimated to be from 0.1 to 0.4 W/kg. © 1990.