The ITU Radiocommunication Assembly considering a)that, in the design of fixed- and broadcasting-satellite services, an accurate knowledge of the distributions in time and space of radiowave propagation phenomena in the lower atmosphere, and of their dependence on various factors, is important to the determination of system performance and of interference to and from space stations;b)that radiowave propagation data for the fixed- and broadcasting-satellite services are restricted to certain areas and link parameters (e.g. frequency, polarization, elevation angle) and that further data are needed.