Concurrent Changepoints in Greenland Ice Core δ18O records and the North Atlantic Oscillation over the Past Millennium

Structural changes, or changepoints, coinciding in multiple ice core records over the Greenland Ice Sheet (GrIS) may reflect a widespread response of GrIS to atmospheric forcing. Thus, better understand how circulation regulate sudden changes δ18O precipitation, we seek synchronous changepoints occurring core-derived time series across and North Atlantic Oscillation (NAO) past millennium. By utilizing Bayesian changepoint detection method, four horizons were revealed: at beginning 20th century, late-15th around turn 11th 10th centuries. Although exhibited distinctive spatial arrangements each horizon, all corresponded NAO, indicative consistent influence on surface