Nonlinear Madden-julian Oscillation Indices Using Kernel Methods
نویسندگان
چکیده
We investigate in this paper the dominant intraseasonal signals in both convection and circulation data using the nonlinear Laplacian spectral analysis (NLSA) method. Three Madden-Julian oscillation (MJO) indices are constructed based on temporal modes extracted from pure cloudiness, lowerand upper-level zonal wind anomalies. All three indices reveal strong intermittency and capture well – through the use of kernel-based similarity methods from machine learning – the inherent nonlinear nature of both convection and circulation in the tropics.
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