Detection of oceanic Rossby waves in the extratropics by complex networks.

This article focuses on using climate networks, a type of complex network based on Pearson correlation of sea level anomaly (SLA) time series, to detect oceanic Rossby waves in the extratropical regions of the global oceans. By constructing directed graphs where nodes represent regular grid points in four oceanic regions (North Pacific, South Pacific, North Atlantic, and South Atlantic-Indian) and links represent statistically significant cross-correlations of SLA, the study identifies westward propagation patterns consistent with Rossby waves. The analysis reveals spatial variations in network flow and estimates wave speeds that align with theoretical and observational expectations, confirming the latitude dependence of Rossby wave speeds. The study concludes that climate networks effectively detect oceanic Rossby waves and suggests their potential application to other oceanic variables for broader dynamical insights.