Parameters of the ionospheric F 2 layer as a source of information on trends in thermospheric dynamics
Tóm tắt
The problem of determining trends in thermospheric dynamics parameters (horizontal winds) based on analysis of trends in various combinations of ionospheric F
2-layer parameters is formulated. The previous attempts of the authors in this direction are briefly described. It is shown that all studied parameters lead to the same result: after the “boundary date” (approximately 1980) a systematic change in these parameters (a long-term trend) is observed, this fact manifesting changes in the dynamical regime of the thermosphere because of cooling and contraction of the entire middle and upper atmosphere. The results of a search for trends in the hmF2 height for the moment (T(ss) + 2 h) are described. These trends are found higher than the hmF2 trends obtained earlier by various authors analyzing the hmF2 behavior at fixed moments of local time.
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