Luni-solar tides in H at stations within the equatorial electrojet

Abstract

The paper describes lunar daily (L) variation at fixed lunar ages and lunar monthly (M) variation at individual solar hours of the horizontal magnetic field, H, at stations close to the magnetic equator for the IGY-IGC period. The Chapman's phase law for the lunar daily variation is shown to be valid for any of the stations. The daily variations of the amplitude of lunar semi-monthly (M₂) tide is very similar to the corresponding S_>q(H) variation. The yearly mean amplitude of L₂ or noon M₂ tide at different stations is directly proportional to the solar diurnal range of H. The phase of M₂ tide for the day-time hours at any of the stations occurs at the same lunar time (Τ) in D-months and at the same lunar age (v) in J-months These results indicate an intimate relation between the lunar tides at the equatorial stations with the electrojet currents in respect to the diurnal as well as longitudinal variations.