Abstract
A space-time spectral analysis of a long time series of observed geopotential heights for each season at several levels and latitudes of the Northern Hemisphere was performed as part of a continuing investigation of large-scale traveling waves. The data set that is analyzed consists of the first six zonal wavenumbers. A discussion emphasizes westward traveling wave 1 with periods near 16 and 5 days which we argue are consistent with external Rossby warm. An additional outstanding feature is an eastward propagating wave 6 which may result from baroclinic instability.
