[P-EM12] Coupling Processes in the Atmosphere-Ionosphere System

[PEM12-P33] Direct Observation of the Space Hurricane Disturbed Polar Thermosphere

Zhi-Feng Xiu¹、*Yu-Zhang Ma¹、Qing-He Zhang¹、Zan-Yang Xing¹、Shun-Rong Zhang²、Yong-Liang Zhang³、Kjellmar Oksavik⁴、Larry Lyons⁵、Michael Lockwood⁶、Yong Wang¹ (1.Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai, China、2.MIT Haystack Observatory, Westford, MA, USA、3.The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA、4.Department of Physics and Technology, University of Bergen, Bergen, Norway、5.Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA, USA、6.Department of Meteorology, University of Reading, Reading, UK)

キーワード：Space Hurricane, Auroral ionosphere, thermosphere-ionosphere coupling

The space hurricane is a three-dimensional magnetic vortex structure with strong flow shears and electron precipitation in the polar cap. This study investigates for the first time how a space hurricane disturbs the polar thermosphere. During the formation and development of the space hurricane, the directional reversal of the horizontal neutral wind and the plasma convection will both be relocated from the poleward auroral oval boundary to the edge of the space hurricane, but the neutral wind responds slower compared to the plasma convection. Strong flow shears in the space hurricane causes enhanced Joule heating in the polar cap, which heats the thermosphere and triggers Atmospheric Gravity Waves (AGWs). Statistical results reveal that significant AGWs mainly are located on the dawnside of the space hurricane, suggesting that the space hurricane plays a significant role in ion-neutral coupling and generation of polar cap AGWs.