Current Development in Theory and Applications of Wavelets
Volume 2, Issue 2, Pages 125 - 136
(August 2008)
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A SPACE-TIME WAVELET SPECTRUM ANALYSIS AND ITS APPLICATION TO TROPICAL ATMOSPHERIC WAVES/OSCILLATIONS
Guojun Gu (USA) and Chidong Zhang (USA)
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Abstract: A space-time wavelet spectrum analysis method is developed to describe local spectral properties (in zonal wavenumber and frequency) of zonally-propagating disturbances. This method combines wavelet transform and conventional space-time spectrum analysis method. For a given variable as a function of longitude and time, this new, hybrid analysis method produces a spectral power function in a 3-dimensional (zonal wavenumber-frequency-longitude) space, in contrast to the conventional spectrum analyses which can only provide 2-dimensional spectra (zonal wavenumber-frequency by the space-time spectrum analysis, frequency-time or zonal wavenumber-longitude by the wavelet analysis). The utility of this 3-dimensional space-time wavelet analysis is demonstrated through examples for planetary and synoptic-scale disturbances in the tropical atmosphere. |
Keywords and phrases: space-time spectrum analysis, wavelet analysis, atmospheric waves. |
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