Figure 4

Vertical mixing term and its constituents during pIOD and nIOD years. Time series of composited (a) vertical mixing term (in °C/month), (b) mixed layer depth (MLD) (in m), (c) difference in temperature between the mixed layer and just below it (in °C), and (d) vertical diffusion coefficient (in \({\text{m}}^{2}\text{/}{\text{s}}\)) anomalies for the pIOD (red), the nIOD (blue), and the sum of pIOD and nIOD events (grey). The closed (open) circles indicate anomalies significant at the 95% (90%) confidence level by a two-tailed t test. The development phase is shaded.