The ITU Radiocommunication Assembly considering a)that accurate, quantitative short-term predictions of ionospheric variations a few hours or days in advance would increase the reliability of radiocommunication and aeronautical radionavigation-satellite services including safetyrelated applications; b)that, in addition to the widespread disturbances associated with major geophysical or solar events that affect the total electron content (TEC), the spatial and temporal gradients of TEC and the occurrence of ionospheric scintillations, there are other hour-to-hour and day-to-day ionospheric variations (which may be local in influence).