Journal cover Journal topic
Annales Geophysicae An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 1.490 IF 1.490
  • IF 5-year value: 1.445 IF 5-year
    1.445
  • CiteScore value: 2.9 CiteScore
    2.9
  • SNIP value: 0.789 SNIP 0.789
  • IPP value: 1.48 IPP 1.48
  • SJR value: 0.74 SJR 0.74
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 88 Scimago H
    index 88
  • h5-index value: 21 h5-index 21
Volume 18, issue 11
Ann. Geophys., 18, 1422–1434, 2000
https://doi.org/10.1007/s00585-000-1422-y
© European Geosciences Union 2000
Ann. Geophys., 18, 1422–1434, 2000
https://doi.org/10.1007/s00585-000-1422-y
© European Geosciences Union 2000

  30 Nov 2000

30 Nov 2000

On the mechanism of the post-midnight winter NmF2 enhancements: dependence on solar activity

A. V. Mikhailov1, M. Förster2, and T. Y. Leschinskaya1 A. V. Mikhailov et al.
  • 1IZMIRAN, Russian Academy of Sciences, Troitsk, Russia
  • 2Max-Planck Institut für extraterrestrische Physik, Garching, Germany

Abstract. The mechanism of the NmF2 peak formation at different levels of solar activity is analyzed using Millstone Hill IS radar observations. The hmF2 nighttime increase due to thermospheric winds and the downward plasmaspheric fluxes are the key processes responsible for the NmF2 peak formation. The electron temperature follows with the opposite sign the electron density variations in this process. This mechanism provides a consistency with the Millstone Hill observations on the set of main parameters. The observed decrease of the nighttime NmF2 peak amplitude with solar activity is due to faster increasing of the recombination efficiency compared to the plasmaspheric flux increase. The E×B plasma drifts are shown to be inefficient for the NmF2 nighttime peak formation at high solar activity.

Key words: Ionosphere (ionosphere-atmosphere interactions; mid-latitude ionosphere; plasma temperature and density)

Publications Copernicus
Download
Citation