The evolution of an ionospheric forecasting service

This paper reviews some the development of the Daily Ionospheric Forecasting Service (DIFS) at the Marconi Research Centre (MRC), Gt. Baddow, UK, since its initial manifestation during the Second World War. It highlights some of the practical aspects of operational forecasting services, such as: physical understanding of the processes involved, ionospheric variability and algorithm development, and the logistics of data collection and forecast distribution. With the gradual emergence of intelligent adaptive systems, with operational automatic link establishment (ALE), the role of long-term predictions and short-term forecasts has changed. The continuing value of forecasts in the management of current HF systems is discussed