Figure 3: Algal Ba/Ca versus salinity.

(a) Gridded salinity data (Met Office Hadley Centre observations data set EN 4.2.02) for the rectangular region depicted in Fig. 1b (56.0577–58.0133° N; 57.0905–61.0455° W) show no signficant correlations to algal Ba/Ca. Algal Ba/Ca versus salinity displayed as scatter plots on (b) annual timescales (1900–2009; r=−0.19, P>0.05; Padj=0.29); and (c) Decadal timescales (1900–2009; n=101, r=−0.35, Padj=0.32).