A case study based on ground observations of the conjugate ionospheric response to interplanetary shock in polar regions

Fang, He and Zejun, Hu and Hongqiao, Hu and Dehong, Huang and Yao, Yu (2021) A case study based on ground observations of the conjugate ionospheric response to interplanetary shock in polar regions. Advances in Polar Science, 32 (2). pp. 141-160.

PDF Download (6MB)

Abstract

Data acquired by imaging relative ionospheric opacity meters (riometers), ionospheric total electron content (TEC) monitors, and three-wavelength auroral imagers at the conjugate Zhongshan station (ZHS) in Antarctica and Yellow River station (YRS) in the Arctic were analyzed to investigate the response of the polar ionosphere to an interplanetary shock event induced by solar flare activity on July 12, 2012. After the arrival of the interplanetary shock wave at the magnetosphere at approximately 18:10 UT, significantly enhanced auroral activity was observed by the auroral imagers at the ZHS. Additionally, the polar conjugate observation stations in both hemispheres recorded notable evolution in the two-dimensional movement of cosmic noise absorption. Comparison of the ionospheric TEC data acquired by the conjugate pair showed that the TEC at both sites increased considerably after the interplanetary shock wave arrived, although the two stations featured different sunlight conditions (polar night in July in the Antarctic region and polar day in the Arctic region). However, the high-frequency (HF) coherent radar data demonstrated that different sources might be responsible for the electron density enhancement in the ionosphere. During the Arctic polar day period in July, the increased electron density over YRS might have been caused by anti-sunward convection of the plasma irregularity, whereas in Antarctica during the polar night, the increased electron density over ZHS might have been caused by energetic particle precipitation from the magnetotail. These different physical processes might be responsible for the different responses of the ionosphere at the two conjugate stations in response to the same interplanetary shock event.

Item Type:	Article
Related URLs:
Keywords:	polar ionosphere, conjugate, interplanetary shock, response, irregularity
Subjects:	Natural Environment > Atmosphere Natural Environment > Space
Organizations:	Unspecified
Date Deposited:	14 Nov 2023 14:38
URI:	http://library.arcticportal.org/id/eprint/2751

Actions (login required)

View Item