Multisensor detection of ionospheric phenomena

For the past several years, observations using a large number of geophysical sensors have been conducted at a site near Boulder, Colo. Data are continuously recorded on magnetic tape and have the advantages of a common time base and the availability of an on-line computer which performs data processing and controls the operation of the station. The original purpose of the installation was to study ground-based techniques for detection of high-altitude nuclear explosions. Scientific studies to which the data have been applied include the changes in the ionosphere during sudden ionospheric disturbances, ionospheric effects which appear to be related to severe thunderstorms, and the characteristics of traveling ionospheric disturbances which are believed to be related to magnetic activity. The system has the capability of automatically detecting sudden ionospheric disturbances and of providing real-time indices of ionospheric and magnetic activity.