Presentation Information
[PEM18-12]Seasonal dependence of the plasmaspheric density along the 210MM: Observations in the northern and southern hemispheres
Sakiko Onoue2, *Hideaki Kawano1, Teiji Uozumi3, Boris Shevtsov4, Sergey Khomutov4, Igor Poddelskiy4, Richard Marshall5, Akimasa Yoshikawa1, group MAGDAS/CPMN3 (1.Department of Earth and Planetary Sciences, Faculty of Science, Kyushu University, 2.Department of Earth and Planetary Sciences, School of Science, Kyushu University, 3.International Center for Space Weather Science and Education, Kyushu University, 4.IKIR FEB RAS, Russia, 5.Space Weather Services section, Bureau of Meteorology, Australia)
In this paper we have applied the cross-phase method and the amplitude-ratio method to the MAGDAS/CPMN ground-magnetometer pairs MGD-PTK (Magadan and Paratunka, located in the Russian Far East) and CAN-HOB (Canberra and Hobart, located in eastern Australia), both along the 210MM (Magnetic Meridian), and identified FLR (field-line resonance) events.
MGD is located at (53.6, 219.1) magnetic latitude and longitude [deg], and PTK is located at (46.2, 226.2). Their L values are 2.9 and 2.1. CAN is located at (-45.7, 226.6), and HOB is located at (-54.2, 226.5). Their L values are 2.1 and 2.9. We have identified the FLR events by using both visual inspection and an automatic-identification computer code.
Although the MGD and PTK (CAN and HOB) are separated by about seven (nine) degrees in magnetic latitudes, which is larger than the typical separation (about 1-2 degrees) to which the cross-phase and amplitude-ratio methods are efficient, but we could identify more than a hundred FLR events a year from the both station pairs, and the FLR events had a fairly continuous coverage.
In this paper we estimate the plasmaspheric density from thus obtained FLR frequencies, and examine their seasonal dependence. The result suggests a weak, but marginally significant seasonal dependence with maxima in winter and minima in summer for the both hemispheres. More details will be discussed at the presentation.
MGD is located at (53.6, 219.1) magnetic latitude and longitude [deg], and PTK is located at (46.2, 226.2). Their L values are 2.9 and 2.1. CAN is located at (-45.7, 226.6), and HOB is located at (-54.2, 226.5). Their L values are 2.1 and 2.9. We have identified the FLR events by using both visual inspection and an automatic-identification computer code.
Although the MGD and PTK (CAN and HOB) are separated by about seven (nine) degrees in magnetic latitudes, which is larger than the typical separation (about 1-2 degrees) to which the cross-phase and amplitude-ratio methods are efficient, but we could identify more than a hundred FLR events a year from the both station pairs, and the FLR events had a fairly continuous coverage.
In this paper we estimate the plasmaspheric density from thus obtained FLR frequencies, and examine their seasonal dependence. The result suggests a weak, but marginally significant seasonal dependence with maxima in winter and minima in summer for the both hemispheres. More details will be discussed at the presentation.