Planktic foraminiferal stable oxygen isotopes of Globigerinoides ruber and Mg/Ca sea surface temperature reconstructions of sediment core RAPID-21-12B from Gardar Drift over the last 230 years

• Main Authors: Hall, Ian R, Boessenkool, K P, Barker, Stephen, McCave, I Nick, Elderfield, Henry
• Format: Dataset
• Language: English
• Published: PANGAEA 2019
• Subjects: Age; BC; Box corer; CD159; Charles Darwin; DEPTH; sediment/rock; Gardar Drift; Globigerina bulloides; δ18O; RAPiD-21-12B; Sea surface temperature; Size fraction 250–315 μm; SST from Mg/Ca ratios; Iceland; north atlantic current; North Atlantic; North Atlantic oscillation
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.899434; https://doi.org/10.1594/PANGAEA.899434

The subpolar North Atlantic Ocean (SPNA) is of key importance for modulating the climate of NW Europe because of heat loss to the atmosphere from the North Atlantic Current. Although hydrographic properties of the surface SPNA vary on interannual to multidecadal timescales, hydrographic time series scarcely extend back beyond the 1950s. We present a 230 year long record of SPNA surface conditions reconstructed from a very high accumulation rate core that also registers changes in deep flow speed in the Iceland Basin. A lagged correlation is observed between the records of deep flow speed and stable oxygen isotopic composition of the surface SPNA (δ18Ow), with strongest correlation when the paleoflow speed record leads by 15–20 years. This offset may to some extent reflect size‐selective biological mixing of the sediment. Nonetheless, these records reveal a decadal‐scale coupling between surface and deep ocean variability over the past 230 years, possibly driven by the North Atlantic Oscillation, with implications for North Atlantic circulation and climate.