Ionospheric disturbances in early July, 1978

Geomagnetic storms caused by the flares of June 20-23, June 27-July 3, and July 5-15 commenced at 2305 UT on July 3, and 0845 UT on July 4, with minor storms both before and after. Three foF2 disturbances were summer-type ionospheric storms with negative phase domination, while fmin disturbances were associated with simple flare activity in the active region of McMath 15403. Observed variations of h'F2, foF2 and fmin, obtained at Wakkanai, Kokubunji, and Okinawa, are presented graphically, as are occurrences of solar flares.