American Geophysical Union Become an AGU Member
Subscribe to AGU Journals		 AGU Home AGU Publications

Read Full Article (file size: 513952 bytes)    Cited by

GEOPHYSICAL RESEARCH LETTERS, VOL. 35, L19502, doi:10.1029/2008GL034470, 2008

A millennial-scale record of Arctic Ocean sea ice variability and the demise of the Ellesmere Island ice shelves

John H. England

Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada


Thomas R. Lakeman

Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada


Donald S. Lemmen

Climate Change Impacts and Adaptation Directorate, Natural Resources Canada, Ottawa, Ontario, Canada


Jan M. Bednarski

Pacific Geoscience Centre, Geological Survey of Canada, Sidney, British Columbia, Canada


Thomas G. Stewart

Malcolm Pirnie, Inc., Sacramento, California, USA


David J. A. Evans

Department of Geography, Durham University, Durham, UK


Abstract

Sea-ice ice shelves, at the apex of North America (>80° N), constitute the oldest sea ice in the Northern Hemisphere. We document the establishment and subsequent stability of the Ward Hunt Ice Shelf, and multiyear landfast sea ice in adjacent fiords, using 69 radiocarbon dates obtained on Holocene driftwood deposited prior to coastal blockage. These dates (47 of which are new) record a hiatus in driftwood deposition beginning ∼5500 cal yr BP, marking the inception of widespread multiyear landfast sea ice across northern Ellesmere Island. This chronology, together with historical observations of ice shelf breakup (∼1950 to present), provides the only millennial-scale record of Arctic Ocean sea ice variability to which the past three decades of satellite surveillance can be compared. Removal of the remaining ice shelves would be unprecedented in the last 5500 years. This highlights the impact of ongoing 20th and 21st century climate warming that continues to break up the remaining ice shelves and soon may cause historically ice-filled fiords nearby to open seasonally.

Received 25 April 2008; accepted 12 August 2008; published 4 October 2008.

Keywords: ice shelves; sea ice; Arctic Ocean.

Index Terms: 0750 Cryosphere: Sea ice (4540); 0728 Cryosphere: Ice shelves; 1605 Global Change: Abrupt/rapid climate change (4901, 8408); 1621 Global Change: Cryospheric change (0776); 9315 Geographic Location: Arctic region (0718, 4207).

Read Full Article (file size: 513952 bytes)    Cited by

Citation: England, J. H., T. R. Lakeman, D. S. Lemmen, J. M. Bednarski, T. G. Stewart, and D. J. A. Evans (2008), A millennial-scale record of Arctic Ocean sea ice variability and the demise of the Ellesmere Island ice shelves, Geophys. Res. Lett., 35, L19502, doi:10.1029/2008GL034470.