Travelling planetary scale waves in the ionosphere

From an analysis of variations in the received daytime phase of long distance, cesium-controlled very low frequency data measured over several longitudinal transmission paths, travelling planetary scale waves were shown to exist at about 70 km for the 1970/71 winter. The movement of these waves at 70 km is compared with the travelling planetary-scale waves in the lower stratosphere as detected by the satellite infrared spectrometer instrument on Nimbus 4 weather satellite during the same period. The VLF-phase data are used to study the major mid-winter warming which occurred during the 1970/71 winter. The results of a power spectral and cross-spectral analysis of the data are also presented and discussed.