A Be production-rate calibration for the Arctic

We present a Baffin Bay Be production-rate calibration derived from glacial deposits in western Greenland and Baffin Island, and test our results against published Be calibration datasets to develop an Arctic Be production rate. Our calibration comprises: (i) Be measurements from moraine boulders linked to a Cdated moraine at Jakobshavn Isfjord in western Greenland, (ii) an independent and previously published Be production rate at Jakobshavn Isfjord and (iii) re-measured Be concentrations from a Baffin Island calibration site that is included in the north-eastern North America dataset. Combined, we calculate a sea-level/high-latitude Be production rate for the Baffin Bay region of 3.96 0.07 atoms g 1 a 1 (Lal/Stone scaling model). After testing the Baffin Bay rate against calibration sites in Norway and north-eastern North America, we calculate a more conservative Arctic production rate of 3.96 0.15 atoms g 1 a . The Baffin Bay and Arctic Be production rates are indistinguishable from the north-eastern North America Be production rate (3.91 0.19 atoms g 1 a ) and yield overall uncertainties of <2–3.7% (1s). These production rates reduce systematic uncertainties in Be-based chronologies of ice-margin change and allow Be-based chronologies to be more confidently compared with high-resolution climate records, such as those from Greenland ice cores. Copyright # 2013 John Wiley & Sons, Ltd.