This introductory text replaces two earlier publications (Davies 1965, 1969). Among the topics: characteristics of waves and plasma, the solar-terrestrial system, the Appleton formula, radio soundings of the ionosphere, morphology of the ionosphere, oblique propagation, importance of amplitude and phase, earth-space propagation. Annotation copyrighted by Book News, Inc., Portland, OR

Especially due to the increasing environmental problems there is a need to collect as many data as possible in the upper atmosphere. This book serves as a general multidisciplinary guide and introduction for a more effective use of the large amount of now available data from the Earth's atmosphere. It also shows the problems of the use of large amounts of time series data - for basic science as well as for environmental monitoring - and the related information systems. The book is aimed for scientists and students interested in the Earth's atmosphere which is vital for the understanding of environmental changes in the global system Earth.

The role of enhanced chemical reaction rates in the formation of the daytime F-region trough is examined. A simple convection model is used to estimate the maximum likely elevation of effective temperature for the ion reaction O+ + N2 yields NO(+)+ N. Under extreme conditions the effective temperature can reach 4000 k resulting in a 30-fold increase in the reaction rate. However, the resulting reduction in F-region electron density is only a factor of 4. Under more usual conditions, the reduction is less than a factor of 2. The actual density reduction factor in the daytime trough is observed to vary between 3 and 10 under normal conditions. Therefore, we conclude that under most circumstances, convection-enhanced chemistry contributes very little to the formation of the daytime trough.