Modified Methods of Estimating Space-Time Spectra from Polar-orbiting Satellite Data Part II : The Wavenumber Transform Method
نویسنده
چکیده
In order to estimate space-time spectra correctly from uneven twice-daily data sampled by a polar-orbiting satellite, the wavenumber transform method (Hayashi, 1980) is modified by the use of a nonorthogonal Fourier inversion. The space-time spectra are obtained from the time-Fourier coefficients of the space-Fourier transforms of the asynoptic field with respect to its frequency-shifted wavenumber. Since this method requires the spatial interpolation of asynoptic data, it is effective only for ultralong waves. The wavenumberfrequency aliasing characteristics are examined and the computer code is exemplified.
منابع مشابه
Modified Methods of Estimating Space-Time Spectra from Polar-Orbiting Satellite Data
A simplification is made of the nonorthogonal Fourier transform method (Salby, 1982) for estimating space-time spectra from uneven twice-daily data sampled by a polar-orbiting satellite. The modified method transforms frequency only by the use of the Galilean transformation, while Salby's method transforms both frequency and wavenumber. Space-time spectra are obtained from the time-Fourier tran...
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تاریخ انتشار 1983