Interhemispheric comparison of GPS phase scintillation at high latitudes during the magnetic-cloud-induced geomagnetic storm of 5–7 April 2010

• Published in: Annales Geophysicae
• Main Authors: P. Prikryl, L. Spogli, P. T. Jayachandran, J. Kinrade, C. N. Mitchell, B. Ning, G. Li, P. J. Cilliers, M. Terkildsen, D. W. Danskin, E. Spanswick, E. Donovan, A. T. Weatherwax, W. A. Bristow, L. Alfonsi, G. De Franceschi, V. Romano, C. M. Ngwira, B. D. L. Opperman
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2011
• Subjects: Science; Q; Physics; QC1-999; Geophysics. Cosmic physics; QC801-809; Antarctic; Arctic; Cambridge Bay; Eureka; Longyearbyen; Mario Zucchelli; South Pole; Zhongshan; Antarc*; South pole
• Online Access: https://doi.org/10.5194/angeo-29-2287-2011; https://doaj.org/article/dddea0fa9523431583216e4c3785049c

Arrays of GPS Ionospheric Scintillation and TEC Monitors (GISTMs) are used in a comparative scintillation study focusing on quasi-conjugate pairs of GPS receivers in the Arctic and Antarctic. Intense GPS phase scintillation and rapid variations in ionospheric total electron content (TEC) that can result in cycle slips were observed at high latitudes with dual-frequency GPS receivers during the first significant geomagnetic storm of solar cycle 24 on 5–7 April 2010. The impact of a bipolar magnetic cloud of north-south (NS) type embedded in high speed solar wind from a coronal hole caused a geomagnetic storm with maximum 3-hourly Kp = 8- and hourly ring current Dst = −73 nT. The interhemispheric comparison of phase scintillation reveals similarities but also asymmetries of the ionospheric response in the northern and southern auroral zones, cusps and polar caps. In the nightside auroral oval and in the cusp/cleft sectors the phase scintillation was observed in both hemispheres at about the same times and was correlated with geomagnetic activity. The scintillation level was very similar in approximately conjugate locations in Qiqiktarjuaq (75.4° N; 23.4° E CGM lat. and lon.) and South Pole (74.1° S; 18.9° E), in Longyearbyen (75.3° N; 111.2° E) and Zhongshan (74.7° S; 96.7° E), while it was significantly higher in Cambridge Bay (77.0° N; 310.1° E) than at Mario Zucchelli (80.0° S; 307.7° E). In the polar cap, when the interplanetary magnetic field (IMF) was strongly northward, the ionization due to energetic particle precipitation was a likely cause of scintillation that was stronger at Concordia (88.8° S; 54.4° E) in the dark ionosphere than in the sunlit ionosphere over Eureka (88.1° N; 333.4° E), due to a difference in ionospheric conductivity. When the IMF tilted southward, weak or no significant scintillation was detected in the northern polar cap, while in the southern polar cap rapidly varying TEC and strong phase scintillation persisted for many hours. This interhemispheric asymmetry is explained by the ...