This directory contains MATLAB code to compute realtime multivariate Madden-Julian Oscillation (RMM) indices using Koopman spectral analysis as described in the paper:

• Lintner, B. R., D. Giannakis, M. Pike, J. Slawinska (2023). Identification of the Madden–Julian Oscillation with data-driven Koopman spectral analysis. Geophys. Res. Lett., 50, e2023GL102743. doi:/10.1029/2023GL102743.

The main driver script is rmmKoopman.m. This script has options to import RMM data into format appropriate for the NLSA code, compute the associated Koopman RMM index values, and output the results in ASCII format.