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Behavior of foF2 and hmF2 after sunset

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Abstract

The time behavior of the foF2 and hmF2 values at the time moment T(ss + 2 h) 2 h after sunset is considered. It is assumed that at this moment, the horizontal winds in the thermosphere in the strongest way influence hmF2 and, therefore, foF2. It is found that a fairly well pronounced and statistically significant change (trend) is observed for the foF2(ss + 2)/foF2(14) ratio, the sign of the change being different for different stations and even different seasons at the same station. A similar picture is obtained for the value of hmF2(ss + 2). It is shown that a positive correlation between the trends of these two values is observed. This confirms the initial concept of the paper that the foF2 and hmF2 trends are caused by long-term trends in the thermospheric dynamics.

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Authors and Affiliations

  1. Institute of Applied Geophysics, Rostokinskaya ul. 9, Moscow, 129128, Russia

    A. D. Danilov

  2. Institute for Space Research, Russian Academy of Sciences, ul. Profsoyuznaya 84/32, GSP-7, Moscow, 117810, Russia

    L. B. Vanina-Dart

Authors
  1. A. D. Danilov
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  2. L. B. Vanina-Dart
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Original Russian Text © A.D. Danilov, L.B. Vanina-Dart, 2010, published in Geomagnetizm i Aeronomiya, 2010, Vol. 50, No. 6, pp. 825–832.

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Danilov, A.D., Vanina-Dart, L.B. Behavior of foF2 and hmF2 after sunset. Geomagn. Aeron. 50, 796–803 (2010). https://doi.org/10.1134/S0016793210060113

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  • DOI: https://doi.org/10.1134/S0016793210060113

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