Specific oscillatory mode in the polar thermosphere

1Fedorenko, AK, 1Zakharov, IV
1Space Research Institute of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine, Kyiv, Ukraine
Kosm. nauka tehnol. 2012, 18 ;(2):26–32
Section: Space and Atmospheric Physics
Publication Language: Ukrainian
Some features of behaviour of middle-scale acoustic gravity waves (AGW) in the polar region are investigated using the «Dynamics Explorer 2» satellite data. It is found that the oscillations of vertical component of velocity z V and relative concentration δn/n occur in phase for these AGW. The properties of the AGW are similar above both polar caps and for different seasons at altitudes from 250 to 350 km. The main characteristics of the polar waves, namely, the horizontal phase speed, period, true horizontal wavelength, vertical wavelength, propagation direction relative to the vertical, are determined. Value z k < 0 points to the wave propagation from sources that are below the satellite. The horizontal phase speed is about 700 m/s and the angle between the wave vector and surface is about 20°.
Keywords: acoustic gravity waves, polar region, «Dynamic Explorer 2»
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