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Information × Registration Number 0210U001648, 0108U000516 , R & D reports Title Analysis and simulation of ionospheric and magnetic disturbances according to satellite measurements in arctic regions popup.stage_title Head Lizunov Georgiy, Registration Date 15-03-2010 Organization Space Research Institute popup.description2 Global distribution of middle-scale acoustic-gravity waves (AGW) is investigated according to DE2 satellite measurements in polar regions. These waves are systematically observed at altitudes of 250-400 km filling in almost the whole arctic areas inside the auroral ovals. The relative amplitudes of neutral density oscillations exceed a few %, sometimes reaching to 10 % that is by order of magnitude greater then the amplitude of oscillations in middle latitudes. The technique for propagation direction definition is elaborated based on the satellite single-point density measurement. It is determined that in wide time zone range (about 6 hours range) AGW systematically propagate from night to day, thus a source of AGW generation is concentrated in night part of auroral ovals and a source is extensive. AGW propagate inwards the ovals and are not practically observed outside the ovals. In a dayside wave activity is abruptly limited at geomagnetic latitudes 65…75°. The effect of spatial coincidence between the regions of reducing AGW intensity and zonal wind flow was revealed. The wave interaction with this flow is supposed to lead to AGW destruction, while AGW energy and momentum converts to the flow. The wave distribution in neutral atmosphere is accompanied by compatible variations of all main parameters: concentration, temperature, pressure, velocity. The comparison of theoretical polarization relations with the course of experimental parameters allow to determine wave-type and main spectral characteristics of AGW. On this base the true horizontal wavelength was determined. It was shown that sources of AGW generation are located lower than satellite orbit and waves propagate quasi-horizontally. Product Description popup.authors Готинян О.Є. Крючков Є.І. Лізунов Г. В. Скороход Т.В. Федоренко А.К. popup.nrat_date 2020-04-02 Close