Abstract
The dynamics of ionospheric troughs that developed during a great geomagnetic storm on 11–13 April 2001 are studied using measurements of electron density obtained by the CHAMP satellite at an altitude of 410–465 km. Subauroral, mid-latitude and low-latitude troughs were observed at nighttime, sometimes simultaneously. The subauroral trough is usually defined as the main ionospheric trough, whereas the mid-latitude trough is associated with the magnetospheric ring current. It appeared at the beginning of the storm recovery phase around latitudes of 40°–45° GMLat (L = 1.7–2.0) and existed for a long period of time throughout the late recovery phase of the residual ring current at latitudes of 50°–55° GMLat (L ~ 2.4–3.0). For the first time, a low-latitude trough was revealed. It developed at latitudes of 34°–45° GMLat (L = 1.45–2.00) in association with the precipitation of energetic particles from the inner radiation belt.
Highlights
The dynamics of ionospheric troughs that developed during a great geomagnetic storm on 11–13 April 2001 are studied using measurements of electron density obtained by the CHAMP satellite at an altitude of 410–465 km
The ionization trough is usually understood as the main ionospheric trough (MIT); during the storm recovery phase, usually at night, another trough, the so-called ring ionospheric trough (RIT) is formed
As the storm recovery phase develops, the MIT returns to quiet latitudes of > 60° GMLat and the RIT can be observed for long periods of time at the typical latitudes of the residual magnetospheric ring current, i.e. 54°–56°
Summary
The dynamics of ionospheric troughs that developed during a great geomagnetic storm on 11–13 April 2001 are studied using measurements of electron density obtained by the CHAMP satellite at an altitude of 410–465 km. As the storm recovery phase develops, the MIT returns to quiet latitudes of > 60° GMLat and the RIT can be observed for long periods of time at the typical latitudes of the residual magnetospheric ring current, i.e. 54°–56°. The analysis of CHAMP satellite data from strong storms events has shown the existence of a third trough at very low latitudes, i.e. approximately 35°–45°. These latitudes correspond to the inner radiation belt (IRB) L = 1.5–2.0. An analysis of the dynamics of all three troughs, i.e. the MIT, RIT and low-latitude trough (LLT), is presented for the magnetospheric storm on 11–13 April 2001. It was recorded for the last time in the Northern hemisphere on pass 20
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
