Propagation directions of acoustic gravity waves above the polar caps of the Earth
|1Fedorenko, AK |
1Space Research Institute of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine, Kyiv, Ukraine
|Kosm. nauka tehnol. 2011, 17 ;(3):34-44|
|Publication Language: Russian|
Propagation directions of middle-scale acoustic gravity waves (AGW) in the polar regions are investigated using the Dynamics Explorer 2 satellite data. It is found that the AGW above the polar caps are systematically propagated opposite to wind at altitudes of 250 to 350 km. The tendency for anti-clockwise rotations of AGW propagation directions is noticeable above the north polar cap and the tendency for clockwise rotations is observed above the south polar cap. The polar waves are gathered in the next main directions: 1) to the magnetic noon that is towards the wind of disturbed polar circulation; 2) to 15-16 hours of magnetic local time that is towards the global ther-mospheric wind blowing from low latitude regions. Under the polar day and polar night conditions the directions of AGW propagations are changed in the both hemisphere according to seasonal reconstruction of polar wind dynamics.
|Keywords: acoustic gravity waves, magnetic noon, ther-mospheric wind|
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