Oxygen isotope ratios, elevation changes and temperature record from the Agassiz ice cap and Greenland ice sheet ...

• Main Authors: Lecavalier, Benoit, Fisher, David A, Milne, Glenn A, Vinther, Bo Møllesøe, Tarasov, Lev, Huybrechts, Philippe, Lacelle, Denis, Main, Bill, Zheng, James, Bourgeois, Jocelyne, Dyke, Arthur
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2019
• Subjects: Agassiz ice cap; Canadian Arctic; Greenland ice sheet; Holocene climate; Ice core; temperature reconstruction; Ellesmere Island; Greenland; Ice cap; ice core; Ice Sheet
• Online Access: https://dx.doi.org/10.1594/pangaea.904116; https://doi.pangaea.de/10.1594/PANGAEA.904116

We present a revised and extended high Arctic air temperature reconstruction from a single proxy that spans the past ∼12,000 y (up to 2009 CE). Our reconstruction from the Agassiz ice cap (Ellesmere Island, Canada) indicates an earlier and warmer Holocene thermal maximum with early Holocene temperatures that are 4-5 °C warmer compared with a previous reconstruction, and regularly exceed contemporary values for a period of ∼3,000 y. Our results show that air temperatures in this region are now at their warmest in the past 6,800-7,800 y, and that the recent rate of temperature change is unprecedented over the entire Holocene. The warmer early Holocene inferred from the Agassiz ice core leads to an estimated ∼1 km of ice thinning in northwest Greenland during the early Holocene using the Camp Century ice core. Ice modeling results show that this large thinning is consistent with our air temperature reconstruction. The modeling results also demonstrate the broader significance of the enhanced warming, with a ... : Supplement to: Lecavalier, Benoit; Fisher, David A; Milne, Glenn A; Vinther, Bo Møllesøe; Tarasov, Lev; Huybrechts, Philippe; Lacelle, Denis; Main, Bill; Zheng, James; Bourgeois, Jocelyne; Dyke, Arthur (2017): High Arctic Holocene temperature record from the Agassiz ice cap and Greenland ice sheet evolution. Proceedings of the National Academy of Sciences, 114(23), 5952-5957 ...