Semi-annual variation in the true height of the F2-peak in low latitudes (at Puerto Rico)

doi:10.1016/0021-9169(73)90014-7

Journal of Atmospheric and Terrestrial Physics

Volume 35, Issue 6, June 1973, Pages 1181-1186

Journal of Atmospher...

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Abstract

Day-to-day values of true height of the F2-peak, h_mF2, at Puerto Rico have been subjected to a statistical analysis to reveal its semi-annual variation. The effects of solar rotation, solar activity and geomagnetic activity have been subtracted from the values of h_mF2 over one year and the remainders have been subjected to harmonic analysis. The results for the six cases of combination of local times (noon and midnight) and years (1959–1961) show that the semi-annual variation in h_mF2 has an amplitude of the order of 10 km and reaches a maximum between the end of March and the beginning of May, the average date being 25 April. This seems to suggest that the semi-annual variations in h_mF2 and in the peak electron density of the F2-layer are in phase, which is unfavourable to the supposition that the semi-annual variation in the F2-region is brought about by changes in atmospheric composition.

References (5)

H.G Mayr et al.
J. geophys. Res.
(1971)
J.O Thomas
Electron Density Profiles in the Ionosphere and Exosphere

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Semi-annual variation in the true height of the F2-peak in low latitudes (at Puerto Rico)

Abstract

J. geophys. Res.

Electron Density Profiles in the Ionosphere and Exosphere