Documents

DOI

  • Benoit Lecavalier
  • David A. Fischer
  • Glenn Milne
  • Bo M Vinther
  • L. Tarasov
  • Philippe Huybrechts
  • Denis Lacelle
  • Brittany Main
  • James Zheng
  • Jocelyne Bourgeois
  • Arthur S. Dyke
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 retreat of the northern ice margin behind its present position in the mid Holocene and a ∼25% increase in total Greenland ice sheet mass loss (∼1.4 m sea-level equivalent) during the last deglaciation, both of which have implications for interpreting geodetic measurements of land uplift and gravity changes in northern Greenland.
Original languageEnglish
Pages (from-to)5952-5957
JournalProceedings of the National Academy of Sciences of the United States of America
Volume114
Issue number23
DOIs
Publication statusPublished - 2017

    Research areas

  • Ice core, temperature reconstruction, Holocene climate, Greenland ice sheet

ID: 37135874