Fig. 4: Amplitude and phase synchronization changes of climate modes.
From: Global climate mode resonance due to rapidly intensifying El Niño-Southern Oscillation
a–e Ensemble-mean moving 21-year seasonally varying (shading) and monthly (blue curve) standard deviation (SD) changes of each climate mode relative to its monthly SD during 2015–2035 (ratio) for the North Atlantic Oscillation (NAO), Tropical North Atlantic (TNA) mode, Indian Ocean Basin (IOB) mode, Indian Ocean Dipole (IOD), and North Pacific Meridional Mode (NPMM) indices, respectively. f–j Ensemble-mean moving 21-year phase synchronization quantified by the histogram of phase differences (shading) between each climate mode and the Niño3.4 index for NAO, TNA, IOB, IOD, and NPMM, respectively. The blue curves in f–j indicate synchronization strength defined by the SD of the histogram density (PDF) of phase differences. The blue shading in a–j indicates the one SD spread among the four ensemble members.
