A. V. Tolmacheva

The variations of the atmospheric parameters on measurements using the artificial periodic irregularities of plasma

The experimental data 2007–2010 on the altitudinal-temporal variations of the neutral atmosphere temperature at lower thermosphere heights are presented. The measurements were carried out by means of the artificial periodic irregularities formed under action of the powerful high frequency radio waves. The temperature and vertical velocity altitudinal variations of different character are compared. The cases of the atmosphere instability growth and following generation of the internal gravity waves are considered. The estimations of the gravity wave dissipation owing to the viscosity and the thermal conductivity are done.

Study of the lower ionosphere using artificial periodic irregularities

We report on the studies of the lower ionosphere with improved height resolution using artificial periodic irregularities. This method is useful for studying the irregular structure of the ionosphere.

Atmospheric Turbulence and Internal Gravity Waves Examined by the Method of Artificial Periodic Irregularities

A method for studying the Earth’s ionosphere at altitudes of the mesosphere and lower thermosphere based on creating artificial periodic irregularities in the ionospheric plasma by means of powerful radio waves is breafly described. Methods for determining the temperature and density of the neutral component and the velocity of vertical and turbulent motions by measuring the characteristics of the signal backscattered by the irregularities are described. The results of experiments performed on a SURA heating facility aimed at a comprehensive investigation of the natural processes occurring in the Earth’s lower ionosphere due to the propagation of atmospheric waves and turbulent phenomena are examined. Based on measurements of the amplitude and phase of the signal scattered by periodic irregularities, the most important characteristics of the neutral and plasma components of the Earth’s atmosphere at altitudes of the mesosphere and lower thermosphere are determined. Further research on the subject is discussed.

Vertical Velocities and Temperature of the Neutral Component in the Upper Atmosphere

Results of measurements of the velocity of the vertical plasma motion and the temperature of the neutral component in the upper atmosphere and comparison of variations in these parameters have been described. The measurements have been carried out by the resonance scattering of radio waves by artificial periodic irregularities in the ionospheric plasma. The irregularities arise when the ionosphere is modificated by a powerful high-frequency radio emission from a Sura midlatitude heating facility. Comparison has been conducted using experimental data on altitude- and time-dependent variations in the above parameters obtained in experiments of 2010 and 2014. It has been shown that, above 100 km, wavelike variations in temperature and velocity are commonly observed simultaneously. In the absence of wavelike variations, there is a tendency to an increase in temperature with an increase in the velocity of the vertical plasma motion regardless of direction. This tendency can be attributed to thermal flows directed upward from the turbulent region of the ionosphere.