Concurrent Changepoints in Greenland Ice Core δ 18 O Records and the North Atlantic Oscillation over the Past Millennium

• Published in: Atmosphere
• Main Authors: István Gábor Hatvani, Dániel Topál, Eric Ruggieri, Zoltán Kern
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2022
• Subjects: Greenland ice cores; Bayesian changepoint detection; ice core δ 18 O; atmospheric circulation; breakpoint; Meteorology. Climatology; QC851-999; Greenland; Greenland ice core; ice core; Ice Sheet; North Atlantic; North Atlantic oscillation
• Online Access: https://doi.org/10.3390/atmos13010093; https://doaj.org/article/1baa502f131f41678abb339faa29ed02

Structural changes, or changepoints, coinciding in multiple ice core records over the Greenland Ice Sheet (GrIS) may reflect a widespread response of the GrIS to atmospheric forcing. Thus, to better understand how atmospheric circulation may regulate sudden changes in δ 18 O of Greenland precipitation, we seek synchronous changepoints occurring in ice core-derived δ 18 O time series across the GrIS and in the North Atlantic Oscillation (NAO) over the past millennium. By utilizing a Bayesian changepoint detection method, four changepoint horizons were revealed: at the beginning of the 20th century, in the late-15th century, and around the turn of the 11th and 10th centuries. Although the changepoints in ice core δ 18 O records exhibited distinctive spatial arrangements in each horizon, all corresponded to changepoints in the NAO, indicative of a consistent atmospheric influence on GrIS surface changes over the past millennium.