A global description of the F-region during the ionospheric storm of 17 December 1971

Total electron content data—observed continuously by means of geostationary radio beacons—provide a good means to study the ionosphere during severe ionospheric storms. Data of 20 sites were collected in order to study the ionospheric storm of 17 December 1971. A remarkable increase in the total electron content occurred at midlatitude stations throughout the northern hemisphere. Stations at auroral and equatorial latitudes also showed sharp increases which were both LT and latitude dependent whereas both sites in the southern hemisphere showed substantial depletions in the total electron content.