Dynamics of the Mesosphere and Lower Thermosphere Based on Results of Observations on the SURA Facility

Abstract

The results of studies of atmospheric dynamics in the altitude range of 60–130 km are presented based on measurements of the velocity of vertical plasma motion, the temperature and density of the neutral component, and the turbopause height. The measurements were carried via resonant scattering of radio waves by artificial periodic inhomogeneities of the ionospheric plasma. The method is based on ionospheric perturbation by powerful high-frequency radio emission, the creation of periodic inhomogeneities in the field of a standing wave, which forms upon reflection from the ionosphere of a powerful radio wave emitted into the zenith, and the location of inhomogeneities by test radio waves. The parameters of the neutral component, the turbulent velocity, and the height of the turbopause are determined from the relaxation time of the signal scattered by the inhomogeneities after the end of the ionospheric impact. The measurement of the phase of the scattered signal makes it possible to determine the rate of vertical plasma motion. The experiments were carried out on a SURA heating facility (56.15° N; 46.11° E). The paper presents and analyzes the time–altitude dependences of the vertical velocity and temperature, which are largely due to the propagation of atmospheric waves during various natural phenomena. The results of determination of the turbopause height and turbulent velocity are presented.