[P-EM11] Effects of recurrent storms: from the heliosphere to the atmosphere

[PEM11-05] First observation of mesosphere response to the geomagnetic forcing

*Wen Yi^1,4,2、Xianghui Xue^1,4,5、Iain Reid^3,2、Joel Younger^3,2、Andrew Spargo²、Damian Murphy⁶、Tingdi Chen^1,4、Xiankang Dou¹ (1.CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China、2.School of Physical Sciences, University of Adelaide, Adelaide、3.ATRAD Pty Ltd., Thebarton, South Australia, Australia、4.Mengcheng National Geophysical Observatory, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China、5.Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China、6.Australian Antarctic Division, Kingston, Tasmania, Australia)

キーワード：meteor radar, mesospheric density, solar wind, solar wind high speed stream

We present a first observation and analysis of 13.5, 9 and 6.75-day periodic oscillations observed in the neutral mesosphere density in the declining phase of solar cycle 23 and 24. Mesospheric densities near 90 km are derived using data from the Davis meteor radar (68.5°S, 77.9°E), Antarctica. Spectral analysis indicates that the pronounced periodicities of 13.5, 9 and 6.75 days observed in the mesosphere densities are associated with variations in solar wind high-speed streams and recurrent geomagnetic activities. A Morlet wavelet analysis shows that the time evolution of the 13.5, 9- and 6.75-day oscillations in the neutral mesosphere densities are similar to those in the solar wind and in planetary magnetic activity index, Kp. These results demonstrate a direct coupling between the upper atmosphere (corona) of the Sun and the Earth’s mesosphere.