(Supplementary Table 4) Data used to calculate offset values in Figure 7 and 8

1: Sources 1) Al-Rousan et al. 2003 2) Thiagarajan et al., 2011 3) LeGrande and Schmidt, 2006 4) Weber and Woodhead, 1971 5) Swart et al., 2009 6) Wainwright and Fry, 1994 7) World Ocean Atlas, 2009 PO4 (Garcia et al., 2010) and regression in Adkins et al., 2003 8) Adkins et al. 2003.Delta47 offset: Based on the inorganic calibration of Ghosh et al., 2006.delta18O offset: Based on the Grossman and Ku (1986) 'all-data' relationship.delta13C offset: Based on Romanek et al. (1992).