The primary objective of this project is to establish a High Frequency (HF) operational service for real-time specification (now-casting) and short-term forecasting of the state of the ionosphere over the eastern Mediterranean region. This real-time service will be based on ionosonde measurements from Cyprus and will involve the application of existing modelling techniques and the development of mathematical methods and visualisation tools for the forecasting and regional mapping of ionospheric characteristics and provision of associated warning information to enhance HF communication systems operating in the region. The forecasts generated by this HF operational service will also involve the use of additional space weather data sources that have become available through the space weather community. The forecasts will be linked directly to HF sky-wave prediction programmes so that HF frequency managers and users will benefit from near real-time updates of environmental conditions as they develop. This will enable the users to adapt to periods of adverse propagation conditions.
The incentive for this initiative stems out of the well-known fact that the day-to-day variability of the critical frequencies (foF2) is unpredictable, with significant variability (>20%) about the monthly median and even greater variability (>40%) during ionospheric storms. This directly affects HF communications by altering the Maximum Usable Frequency (MUF). For HF skywave operators’ frequency schedules are very important, and are planned several months in advance.
This ionospheric operational service is expected to complement the operation of a recently deployed HF spectral interference monitoring system in Cyprus and enhance its functionality in the frames of real-time monitoring of regional HF propagation conditions to advise operators on typical interference occupancy levels, and assist in the planning of frequency usage and management. The operation of the proposed forecasting service is considered quite beneficial in the case of Cyprus (especially in the context of defence communication systems) where the so-called near vertical incidence sky-wave (NVIS) mode of propagation is the preferred mode of HF communication networks due to terrain imposed limitations.