Fig. 6: Comparison of geochemical records with insolation and atmospheric CO2 across the mid-Pliocene M2 glaciation.
From: Major sea level fall during the Pliocene M2 glaciation
a Atmospheric CO2 derived from δ11B of G. ruber at ODP Site 99910. b Summer insolation at 65 °N (June; red line) and 65 °S (December; blue line)11. c Seawater δ18O (δ18OSW) at ODP Sites 982 (red circles) and 1241 (blue diamonds). d Melonis spp. Mg/Ca bottom water temperatures (BWT) at ODP Sites 982 (red circles) and 1241 (blue diamonds). e Sea surface temperature (SST) at ODP Site 982 (red circles)61, 1241 (blue diamonds)62 and ODP Site 999 (orange triangles)7. f Fish debris Nd isotope data (εNd) at IODP Site U1313 (red circles) and ODP Site 1267 (blue diamonds)64. The blue band highlights the decreasing BWT aligned with the cooling of northern hemisphere SST, and the increasing εNd at ODP Site 1267 while the atmospheric CO2 was relatively high; The yellow band highlights the first phase of sea level fall aligned with a northern hemisphere summer insolation minima and decreasing atmospheric CO2; The orange band highlights the second phase of sea level fall aligned with a southern hemisphere summer insolation minima and relatively low atmospheric CO2.
