Fig. S2. Temporal change in the first three axes of a principal components analysis (PCA) on five environmental variables: monthly temperature anomalies at three lightstations (sea surface temperature at Pine and McInnes Islands, air temperature at Addenbroke Island) and moshtly surface salinity anomalies at Pine and McInnes Islands. The PCA used only times shared by all datasets (1978-2020), but anomalies are calculated from all available data. Lighter lines show monthly PCA values, while the darker lines are LOESS smoothers. Survey years are noted with magenta tick marks. Note how anomalous conditions continued in the region, even after the 2014-2016 marine heatwave ended elsewhere.