Mg/Ca ratios in the planktonic foraminifer Neogloboquadrina pachyderma (sinistral) in the northern North Atlantic/Nordic Seas

Abstract

In core top samples in the Nordic Seas, Mg/Ca ratios of N. pachyderma (sin.) are generally consistent with previous high-latitude calibration data but do not reflect the modern calcification temperature gradient from 2°C in the northwest to 8°C in the southeast. This is because Mg/Ca ratios in foraminiferal shells from the central Nordic Seas are ∼0.4 mmol/mol higher than expected from calibrations of Nurnberg (1995) and Elderfield and Ganssen (2000). The enhanced Mg/Ca ratios are observed in an area with low sedimentation rates (