Seasonal and solar cycle variations of spread F at the equatorial anomaly crest zone.

Abstract

The spread F data obtained at Taipei (25.00°N; 121.53°E geographic and 14.04°N; 191.47°E geomagnetic) and Chungli (24.95°N; 121.23°E geographic and 13.98°N; 191.19°E geomagnetic) during the period from 1960 to 1982 were used to analyze the seasonal and solar cycle variations of frequency and range type spread F at the equatorial anomaly crest zone. By use of superposed epoch method, the geomagnetic activity effects on the occurrences of frequency and range type spread F were also analyzed.