Lunar tidal variations in ƒ₀F₂ in the american zone during the years of low solar activity at huancayo, panama and buenos aires-a geomagnetic anomaly effect

Abstract

Chapman’s Phase Rule L = Σ ⁴_n=1C_nsin{n_τ+(n-2)υ+α_n} shown by him to be true for geomagnetic data is shown to be valid for the lunar oscillations in ƒ₀F₂ also at the tropical latitude stations Panama and Buenos Aires. Lunar semi-monthly (M₂) oscillations in ƒ₀F₂ at Panama are significantly larger during the day hours with a maximum amplitude near noon, while at Buenos Aires the tidal amplitudes are significant for all hours of the day and night and the maximum amplitude occurs in the afternoon around 15 hours. Regarding seasonal variation, the amplitude of lunar semi-diurnal or semi-monthly tides is largest during December solstices and least during June solstices.