Extended Data Fig. 4: Regression analysis between reconstructed SST and abundance of upwelling indicators.

a, \({{\rm{TEX}}}_{86}^{{\rm{H}}}\)-based SST (red diamonds, upper left vertical axis), protoperidinioid abundance (percentage of total dinocyst assemblage; brown dots, right vertical axis) and TOC (percentage of sediment; black dots, lower left vertical axis) records of ODP Site 959. Dashed lines represent a hiatus in Site 959. Age is in GTS2012. b, Regression analysis between SST and percentage of protoperidinioid dinocysts of total dinocyst assemblage, showing a non-significant relationship with a very low fit (brown line, 90% confidence interval shown as brown shading; R² = 0.00, P = 0.75) and a better fit (R² = 0.35) that is significant (P < 0.01) when only the late Eocene (post-MECO) part of the record is considered (blue–grey line; 90% confidence interval is shown as blue–grey shading). c, Regression analysis between SST and percentage of TOC in sediment, showing a significant negative correlation for the whole record (R² = 0.39, P < 0.001; dark-grey line, with the 90% confidence interval shown as dark-grey shading) and the late Eocene subset (R² = 0.37, P < 0.01; blue–grey line, with the 90% confidence interval shown as blue–grey shading).