North Atlantic Globorotalia inflata coretop Mg/Ca calibrations and temperature reconstructions over Termination I

Abstract

Mg/Ca ratios from planktonic foraminifera are widely used as an independent proxy for ocean temperature. The choice of calibration is vital for reconstructing meaningful temperatures. We present preliminary results based on a new Mg/Ca-temperature calibration (Mg/Ca = 0.92e(0.039T)) for the thermocline-dwelling foraminifera Globorotalia inflata, derived using a suite of North Atlantic coretops. The downcore Mg/Ca record from core SU90-03 (40 degrees N, 32 degrees W) was used to compare how our new and existing calibrations performed for the Holocene and over the large scale change associated with Termination I.