Evolution of Solar and Geomagnetic Activity Indices, and Their Relationship: 1960 – 2001
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We employ annually averaged solar and geomagnetic activity indices for the period 1960 – 2001 to analyze the relationship between different measures of solar activity as well as the relationship between solar activity and various aspects of geomagnetic activity. In particular, to quantify the solar activity we use the sunspot number R s, group sunspot number R g, cumulative sunspot area Cum, solar radio flux F10.7, and interplanetary magnetic field strength IMF. For the geomagnetic activity we employ global indices Ap, Dst and Dcx, as well as the regional geomagnetic index RES, specifically estimated for the European region. In the paper we present the relative evolution of these indices and quantify the correlations between them. Variations have been found in: i) time lag between the solar and geomagnetic indices; ii) relative amplitude of the geomagnetic and solar activity peaks; iii) dual-peak distribution in some of solar and geomagnetic indices. The behavior of geomagnetic indices is correlated the best with IMF variations. Interestingly, among geomagnetic indices, RES shows the highest degree of correlation with solar indices.
KeywordsCross-correlation Geoeffectiveness Geomagnetic global and regional activity indices Solar activity indices
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- Campbell, W.H.: 2003, Introduction to Geomagnetic Fields, Cambridge University Press, Cambridge, 103 – 173. Google Scholar
- Georgieva, K., Kirov, B., Gavruseva, E.: 2006, Geoeffectiveness of different solar drivers, and long term variations of the correlation between sunspot and geomagnetic activity. Phys. Chem. Earth 31, 81 – 87. Google Scholar
- Georgieva, K., Kirov, B., Gavruseva, E.: 2010, Solar dynamo and geomagnetic activity. ArXiv:1003.2533.
- Guarnieri, F.L., Tsurutani, B.T., Gonzalez, W.D., Gonzalez, A.L.C., Grande, M., Soraas, F., Ech, E.: 2006, ICME and CIR storms with particular emphasis on HILDCAA events. In: Gopalswamy, N., Bhattacharyya, A. (eds.) Solar influence on the Heliosphere and Earth’s Environment: Recent Progress and Prospects, Indian Institute of Geomagnetism, Mumbai, 266 – 300. Google Scholar
- Hargreaves, J.K.: 1992, The Solar-Terrestrial Environment, Cambridge University Press, Cambridge, 390 – 402. Google Scholar
- Hathaway, D.H.: 2010, The solar cycle. Living Rev. Solar Phys. 7(1). Google Scholar
- Jacobs, J.A.: 1987, Geomagnetism, Vol. 1, Academic Press, London, 249 – 512. Google Scholar
- Kivelson, M.G., Russel, C.T.: 1995, Introduction to Space Physics, Cambridge University Press, Cambridge, 289 – 291. Google Scholar
- Mandea, M., Thèbault, E.: 2007, The Changing Faces of the Earth’s Magnetic Field: A Glance at the Magnetic Lithospheric Field, from Local and Regional Scales to a Planetary View, Commission for the Geological Map of the World, 16 – 41. ISBN 978-2-9517181-9-7. Google Scholar
- Schwenn, R.: 2006, Space weather: The solar perspective. Living Rev. Solar Phys. 3(2). Google Scholar
- Svalgaard, L., Cliver, E.W.: 2007, A floor in the solar wind magnetic field. Astron. J. 661, 203 – 206. Google Scholar
- Verbanac, G., Vršnak, B., Živković, S., Hojsak, T., Veronig, A.M., Temmer, M.: 2011b, Solar wind high-speed streams and related geomagnetic activity in declining phase of solar cycle 23. Astron. Astrophys. accepted. Google Scholar
- Webb, D.F.: 2002, CMES and the solar cycle variation in their geoeffectiveness. In: Wilson, A. (ed.) Proceedings of the SOHO 11 Symposium on from Solar Min to Max: Half a Solar Cycle with SOHO SP-508, ESA, Noordwijk, 409 – 419. Google Scholar