Scintillation observations of VHF and UHF transmissions from geostationary satellites at Goose Bay have been used to study the average characteristics of the high latitude irregularity region. The paper describes the average time development and mean diurnal pattern of irregularities during 58 magnetic storms in 1971-1976. The diurnal variation at Goose Bay shows two peaks of scintillation activity. One peak occurs during the afternoon hours, while the second occurs during the night. The average diurnal pattern is independent of type of storm. diurnal and seasonal effects appear only in the first day of storm commencement and not in the following days which show a very similar diurnal picture.

Scintillation observations of VHF and UHF transmissions from geostationary satellites at Goose Bay have been used to study the average characteristics of the high latitude irregularity region. The paper describes the average time development and mean diurnal pattern of irregularities during 58 magnetic storms in 1971-1976. The diurnal variation at Goose Bay shows two peaks of scintillation activity. One peak occurs during the afternoon hours, while the second occurs during the night. The average diurnal pattern is independent of type of storm. diurnal and seasonal effects appear only in the first day of storm commencement and not in the following days which show a very similar diurnal picture.

In the past two decades a succession of direct observations by satellites, and of extensive computer simulations, has led to the realization that the polar ionosphere plays a principal role in large-scale magnetospheric processes - a manifestation of the physics linkage involved in solar-terrestrial interactions. Spatial/temporal variations in high-latitude electromagnetic phenomena, such as dynamic aurorae, electric fields and currents, have proved to be extremely complex. Now the challenge is to comprehend the vast amount of complicated measurements made in this magnetosphere-ionosphere sysstem of the Earth. This book addresses the electrical coupling between the hot, but dilute, magnetospheric plasma and the cold, but dense, plasma in the ionosphere. In five major chapters, this book presents: - basic properties of magnetosphere-ionosphere coupling; - morphology of electric fields and currents at high latitudes; - global modeling of magnetosphere-ionosphere coupling; - modeling of ionospheric electrodynamics; - current issues, such as auroral particle acceleration, substorms, penetration of high-latitude fields into low latitudes.

This book is a multi-author treatise on the most outstanding research problems in the field of the aeronomy of the Earth’s atmosphere and ionosphere, encompassing the science covered by Division II of the International Association of Geomagnetism and Aeronomy (IAGA). It contains several review articles and detailed papers by leading scientists in the field. The book is organized in five parts: 1) Mesosphere-Lower Thermosphere Dynamics and Chemistry; 2) Vertical Coupling by Upward Propagating Waves; 3) Ionospheric Electrodynamics and Structuring; 4) Thermosphere- Ionosphere Coupling, Dynamics and Trends and 5) Ionosphere-Thermosphere Disturbances and Modeling. The book consolidates the progress achieved in the field in recent years and it serves as a useful reference for graduate students as well as experienced researchers.

Based on papers from an AGU Chapman Conference on Solar Wind-Magnetosphere Coupling, held at the Jet Propulsion Laboratory of the California Institute of Technology, Pasadena, Calif., Feb. 12-15, 1985.