Magnetic Disturbances and Region F2 of the Ionosphere

§ 1. Introduction—In a recent publication by Bannon, Higgs, Martyn and Munro [see 1 of “References” at end of paper] it was shown, by statistical methods, that there is a connection between electron‐density in region F2 of the ionosphere, and meteorological conditions at the ground. The maximum density at noon is, on the average, greater on a non‐frontal than on a frontal day. From March 1937 to October 1938, inclusive, for the Commonwealth Solar Observatory, Mount Stromlo, Canberra (latitude 35° 20′ south, longitude 149° 10′ east) this average noon density for the non‐frontal day exceeded that for the frontal day by 11 per cent. The excess at the Liverpool, New South Wales, field‐station (latitude 33° 55′ south, longitude 150° 59′ east) for the same period was six per cent.