Variation with lunar phase of midday critical frequencies and heights of the F2 layer over Ahmedabad and other low latitude stations

The paper contains an analysis of the variation of the midday values of foF₂, h′F₂ and hpF₂ with lunar phase at Ahmedabad during the years 1954 and 1955 and of foF₂ alone at Bombay, Madras and Tiruchirapalli during 1954. It is found that while the semidiurnal lunar tidal variations at Ahmedabad and Bombay agree in phase with those observed at middle latitudes, the phase reverses in direction between Bombay and Madras. The results are compared with those relating to Huancayo and Singapore.