Applications of asynoptic space-time Fourier transform methods to scanning satellite measurements

Abstract

A method has been tested and applied to soundings of brightness temperature taken by polar-orbiting satellites. When applied to measurements from instruments with multiple-scan tracks, a large number of latitudinally closely spaced spectra results, which enables one to average over latitude instead of or in addition to conventional frequency averaging to achieve greater statistical reliability and better signal-to-noise ratio. Some results of applying the method to real data are presented. Several well-known waves are identified, as well as two previously unreported small-amplitude spectral peaks corresponding to waves in the Southern summer stratosphere having wavenumber 7 and a period of 2.09-2.97 d westward, and wavenumber 6 with a period of 4.17-5.90 d eastward. -from Authors