11:00 〜 11:15
[PEM11-02] Ionospheric anomalies during magnetic storms in 2015-2017: features, intensity and dynamics
キーワード：ionosphere , magnetic storms , data analysis
The strong irregular changes are observed in the ionosphere during solar events and magnetic storms and lead to the formation of irregularities and occurrence of positive and negative ionospheric storms [1, 2]. Ionospheric irregularities have a complex space-time distribution and a random nature, many aspects of which have not been sufficiently studied [ex. 1]. The problem of prediction and timely detection of irregularities that have a negative impact on modern technical systems is also a very relevant [1, 2]. In spite of the intensive development of data analysis methods and information technologies, an effective solution of this problem has not been currently found [ex. 2].
In this paper, the ionospheric parameter variations were studied during strong and moderate magnetic storms from 2015 to 2017. The ionospheric data of Paratunka (Russia, Kamchatka), Wakkanai (Japan) and Norfolk (Australia) were analyzed (http://spidr.ionosonde.net/spidr and http://wdc.nict.go.jp). The research is based on the application of new methods for modeling and analysis of ionospheric data, described in the paper [3]. As distinct from the traditional approaches and techniques [4, 5] (median methods, IRI model), these methods allow us to more efficient detect anomalous changes in the ionospheric parameters and estimate their characteristics.
In the course of the investigation, ionospheric disturbances occurring on the eve and during magnetic storms were detected in the analyzed areas (fig. 1). Their features, dynamics and intensity were studied. The study results showed high probability of the occurrence of long-term (from 10-15 hours to one and a half day) increases in the ionospheric parameters (positive ionospheric storms) on the eve of magnetic storms, which agrees with the numerous observations described in the paper [1]. The comparison of the obtained results with the space weather data indicates solar nature of detected anomalous changes in the ionosphere. In this case, these effects can be used as precursors of magnetic storms (as an additional factor), which determines their applied significance. During the main phase of magnetic storms, the ionospheric process dynamics significantly changes and a long-time decrease (from 12 hours to several days) in the electron concentration (negative ionospheric storms) are observed.
The paper was supported by RSF Grant No. 14-11-00194. The authors are grateful to the organizations recording the data which were applied in the paper.
1. Danilov A.D. Ionospheric F-region response to geomagnetic disturbances // Advances in Space Research. 2013. Vol. 52. No. 3. pp. 343–366.
2. Nakamura M., Maruyama T., Shidama Y. Using a neural network to make operational forecasts of ionospheric variations and storms at Kokubunji, Japan // Journal of the National Institute of Information and Communications Technology. 2009. Vol. 56. pp. 391–406.
3. Mandrikova O.V., Fetisova N.V., Polozov Y.A., Solovev I.S., Kupriyanov M.S. Method for modeling of the components of ionospheric parameter time variations and detection of anomalies in the ionosphere coupling of the high and mid latitude ionosphere and its relation to geospace dynamics // Earth, Planets and Space. 2015. Vol. 67. No 1. pp. 131-146. DOI: 10.1186/s40623-015-0301-4
4. Mikhailov et al. A method for foF2 monitoring over Spain using the El Arenosillo digisonde current observations // Annals of Geophysics. 1999. Vol. 42 (4). doi:10.4401/ag-3748.
5. Bilitza, D. International Reference Ionosphere 2007: Improvement sand new parameters / D. Bilitza, B.W. Reinisch // Advances in space research. – 2008. – Vol. 42. – P. 599–609.
In this paper, the ionospheric parameter variations were studied during strong and moderate magnetic storms from 2015 to 2017. The ionospheric data of Paratunka (Russia, Kamchatka), Wakkanai (Japan) and Norfolk (Australia) were analyzed (http://spidr.ionosonde.net/spidr and http://wdc.nict.go.jp). The research is based on the application of new methods for modeling and analysis of ionospheric data, described in the paper [3]. As distinct from the traditional approaches and techniques [4, 5] (median methods, IRI model), these methods allow us to more efficient detect anomalous changes in the ionospheric parameters and estimate their characteristics.
In the course of the investigation, ionospheric disturbances occurring on the eve and during magnetic storms were detected in the analyzed areas (fig. 1). Their features, dynamics and intensity were studied. The study results showed high probability of the occurrence of long-term (from 10-15 hours to one and a half day) increases in the ionospheric parameters (positive ionospheric storms) on the eve of magnetic storms, which agrees with the numerous observations described in the paper [1]. The comparison of the obtained results with the space weather data indicates solar nature of detected anomalous changes in the ionosphere. In this case, these effects can be used as precursors of magnetic storms (as an additional factor), which determines their applied significance. During the main phase of magnetic storms, the ionospheric process dynamics significantly changes and a long-time decrease (from 12 hours to several days) in the electron concentration (negative ionospheric storms) are observed.
The paper was supported by RSF Grant No. 14-11-00194. The authors are grateful to the organizations recording the data which were applied in the paper.
1. Danilov A.D. Ionospheric F-region response to geomagnetic disturbances // Advances in Space Research. 2013. Vol. 52. No. 3. pp. 343–366.
2. Nakamura M., Maruyama T., Shidama Y. Using a neural network to make operational forecasts of ionospheric variations and storms at Kokubunji, Japan // Journal of the National Institute of Information and Communications Technology. 2009. Vol. 56. pp. 391–406.
3. Mandrikova O.V., Fetisova N.V., Polozov Y.A., Solovev I.S., Kupriyanov M.S. Method for modeling of the components of ionospheric parameter time variations and detection of anomalies in the ionosphere coupling of the high and mid latitude ionosphere and its relation to geospace dynamics // Earth, Planets and Space. 2015. Vol. 67. No 1. pp. 131-146. DOI: 10.1186/s40623-015-0301-4
4. Mikhailov et al. A method for foF2 monitoring over Spain using the El Arenosillo digisonde current observations // Annals of Geophysics. 1999. Vol. 42 (4). doi:10.4401/ag-3748.
5. Bilitza, D. International Reference Ionosphere 2007: Improvement sand new parameters / D. Bilitza, B.W. Reinisch // Advances in space research. – 2008. – Vol. 42. – P. 599–609.