The duration of the Bølling-Allerød period (Greenland Interstadial 1) in the GRIP ice core

• Published in: Annals of Glaciology
• Main Authors: Seierstad, Inger K., Johnsen, Sigfús J., Vinther, Bo M., Olsen, Jesper
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2005
• Subjects: Greenland; Annals of Glaciology; GRIP; ice core
• Online Access: https://pure.au.dk/portal/da/publications/the-duration-of-the-boellingalleroed-period-greenland-interstadial-1-in-the-grip-ice-core(0d76ba1d-ab70-4f92-85bf-40b30a75b476).html; https://doi.org/10.3189/172756405781812556; http://www.scopus.com/inward/record.url?scp=33748305601&partnerID=8YFLogxK

A new dating of the Bølling-Allerød period (Greenland Interstadial event 1) in the GRIP ice core is presented. Newly measured profiles of δD and δ 18 O, as well as existing profiles of Ca 2+ , NH 4 + , dust and NO 3 - , have been used for the dating. As seasonal variations can be observed in all six components, it was possible to simultaneously count annual layers in the profiles in order to obtain a multi-parameter dating. The new data presented in this study include a total of 36.85 m of stable-isotope profiles of 1 cm resolution from five sections of the Bølling-Allerød period in the GRIP ice core. The annual-layer counting suggests a duration of the complete Bølling-Allerød period, as revealed in the GRIP ice core, of 1627 ± 52 years. This estimate contrasts with an earlier finding from the same GRIP ice core, where the Bølling-Allerød was found to span 2168 years (Hammer, in press). This estimate was based on layer counting, using dust concentrations only.