Numerical methods are developed for producing worldwide, long-term predictions of ionospheric characteristics. The methods are based on analyses of series of coefficients defining numerical maps, which take into account both annual and solar cycle variations of the ionosphere. The end product is a five-dimensional numerical map depending on two geographic coordinates, time of day (universal time), time of year, and solar index. Predicted numerical maps in geographical and universal time coordinates are obtained by specifying the month and a predicted value of solar index. The methods are applied to foF2 monthly medians, using for the analysis a series of 60 numerical maps from January 1954 through December 1958, Predicted and observed values of the characteristics are compared for a large sample of data.

This book describes how to predict and forecast the state of planet Earth’s ionosphere under quiet and disturbed conditions in terms of dynamical processes in the weakly ionized plasma media of the upper atmosphere and their relation to available modern measurements and modelling techniques. It explains the close relationship between the state of the media and the radio wave propagation conditions via this media. The prediction and forecasting algorithms, methods and models are oriented towards providing a practical approach to ionospherically dependent systems design and engineering. Proper understanding of the ionosphere is of fundamental practical importance because it is an essential part of telecommunication and navigation systems that use the ionosphere to function or would function much better in its nonappearance on the Earth and on any planet with an atmosphere.