Abstract

The use of Mg/Ca in marine carbonates as a paleothermometer has been challenged by observations that implicate salinity as a contributing influence on Mg incorporation into biotic calcite and that dissolution at the sea‐floor alters the original Mg/Ca. Yet, these factors have not yet been incorporated into a single calibration model. We introduce a new Bayesian calibration for Globigerinoides ruber Mg/Ca based on 186 globally distributed core top samples, which explicitly takes into account the effect of temperature, salinity, and dissolution on this proxy. Our reported temperature, salinity, and dissolution (here expressed as deep‐water ) sensitivities are (±2σ) 8.7±0.9%/°C, 3.9±1.2%/psu, and 3.3±1.3%/μmol.kg−1 below a critical threshold of 21 μmol/kg in good agreement with previous culturing and core‐top studies. We then perform a sensitivity experiment on a published record from the western tropical Pacific to …

Date

January 1, 1970

Authors

D Khider, G Huerta, C Jackson, LD Stott, J Emile‐Geay

Journal

Geochemistry, Geophysics, Geosystems

Volume

16

Issue

9

Pages

2916-2932