Variability in the Fl and F2 region electron density during a geomagnetic activity at mid-latitude

Abstract

This paper investigates the variation in the F1 and F2 region electron density during a geomagnetic activity, at East Asian mid-latitude stations. In this analysis, we have employed D(foF1) and D(foF2) representing deviation of the critical frequency for the F1 and F2 ionospheric regions respectively. The F1 region appears to be much more stable than the F2 layer during the storm event, as there is no significant effect on the F1 layer in most of the ionospheric stations under investigation. It was also observed that independent of the sign of the storm effect on NmF2, the electron density, if any, in the F1 region is always negative. Moreover, no F1 ionospheric response was observed at midnight (0000UT) throughout the storm event in all the stations; but recorded its maximum effects between 0600UT-1800UT during the day. Conclusively, there is a considerable intra-hour variability of F2 electron density NmF2 during ionospheric disturbances.

Keywords: Electron density, geomagnetic storm, critical frequency, ionospheric response.