Progress in refining the global radiocarbon calibration curve using New Zealand kauri (Agathis australis) tree-ring series from Oxygen Isotope Stage 3

• Buried Agathis australis (kauri) wood exists across the full time-span of 14C.
• Bayesian 14C wiggle-matching of kauri sequences to 3 calibration datasets.
• The new Lake Suigetsu 14C calibration dataset provides the most robust fit.
• Demonstrates the potential of kauri for refining the 14C calibration curve.

Ancient kauri (Agathis australis) buried in bogs across Northland, New Zealand, provide potential for a continuous high-precision radiocarbon calibration curve that extends to the full chronologic range of the dating method. Here we report four new tree-ring series which in addition to previous work represent some 5312 years across Oxygen Isotope Stage 3, a period during which human evolution, migration and extinction took place against a backdrop of extreme and abrupt global climate and environmental change. We compare our radiocarbon-dated series against three different calibration datasets and find considerable differences in the wiggle-matched solutions, demonstrating the difficulty in undertaking high-precision correlation between ice, marine and terrestrial sequences. One way around the apparent impasse is the use of 10Be in the Greenland and Antarctic ice cores to precisely link to kauri 14C from which a decadally/bidecadally-resolved floating ‘calibration’ dataset can be generated.