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Acta Geophysica

, Volume 58, Issue 3, pp 491–512 | Cite as

DIAS effective sunspot number as an indicator of the ionospheric activity level over Europe

  • Ioanna TsagouriEmail author
  • Bruno Zolesi
  • Ljiljana R. Cander
  • Anna Belehaki
Article

Abstract

DIAS (European Digital Upper Atmosphere Server) effective sunspot number — R12eff was recently introduced as a proxy of the ionospheric conditions over Europe for regional ionospheric mapping purposes. Although a pre-processing step for the real-time update of the Simplified Ionospheric Regional Model (SIRM) to real-time conditions, R12eff is available in real time by DIAS system (http://dias.space.noa.gr) for independent operational use. In this paper we discuss the efficiency of R12eff to specify ionospheric conditions over Europe. For this purpose, the diurnal R12eff’s reference pattern was determined on monthly basis and for different solar cycle phases. The deviation of the real-time R12eff estimates from the reference values, ΔR12eff was found to be highly correlated with the foF2 storm-time disturbances, especially during large scale effects indicating that DIAS-R12eff can provide a reliable estimator of the ionospheric activity level over a substantial part of Europe and a powerful tool for ionospheric specification applications.

Key words

effective sunspot number mid-latitude ionosphere ionospheric disturbances 

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Copyright information

© © Versita Warsaw and Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Ioanna Tsagouri
    • 1
    Email author
  • Bruno Zolesi
    • 2
  • Ljiljana R. Cander
    • 3
  • Anna Belehaki
    • 1
  1. 1.National Observatory of AthensInstitute for Space Applications and Remote SensingAthensGreece
  2. 2.Istituto Nazionale di Geofisica e VulcanologiaRomeItaly
  3. 3.STFC, Rutherford Appleton LaboratoryChiltonUK

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