Temperature reconstruction from 10 to 120 kyr b2k from the NGRIP ice coreShow others and affiliations
Responsible organisation
2014 (English)In: Climate of the Past, ISSN 1814-9324, E-ISSN 1814-9332, Vol. 10Article in journal (Refereed) Published
Abstract [en]
In order to reconstruct the temperature of the North Greenland Ice Core Project (NGRIP) site, new measurements of delta N-15 have been performed covering the time period from the beginning of the Holocene to Dansgaard-Oeschger (DO) event 8. Together with previously measured and mostly published delta N-15 data, we present for the first time a NGRIP temperature reconstruction for the whole last glacial period from 10 to 120 kyr b2k (thousand years before 2000 AD) including every DO event based on delta N-15 isotope measurements combined with a firn densification and heat diffusion model. The detected temperature rises at the onset of DO events range from 5 degrees C (DO 25) up to 16.5 degrees C (DO 11) with an uncertainty of +/- 3 degrees C. To bring measured and modelled data into agreement, we had to reduce the accumulation rate given by the NGRIP ss09sea06bm timescale in some periods by 30 to 35 %, especially during the last glacial maximum. A comparison between reconstructed temperature and delta O-18(ice) data confirms that the isotopic composition of the stadial was strongly influenced by seasonality. We evidence an anticorrelation between the variations of the delta O-18(ice) sensitivity to temperature (referred to as alpha) and obliquity in agreement with a simple Rayleigh distillation model. Finally, we suggest that alpha might be influenced by the Northern Hemisphere ice sheet volume.
Place, publisher, year, edition, pages
2014. Vol. 10
Keywords [en]
last glacial period abrupt climate-change younger dryas termination dansgaard-oeschger events air isotopic measurements north-atlantic greenland ice polar ice continuous record heinrich events Geology Meteorology & Atmospheric Sciences
Research subject
SWEDARCTIC 1997, NordGRIP 1997; SWEDARCTIC 1998, NordGRIP 1998; SWEDARCTIC 1999, NordGRIP 1999; SWEDARCTIC 2000, NordGRIP 2000; SWEDARCTIC 2001, NordGRIP 2001; SWEDARCTIC 2002, NordGRIP 2002; SWEDARCTIC 2003, NordGRIP 2003; SWEDARCTIC 2004, NordGRIP 2004
Identifiers
URN: urn:nbn:se:polar:diva-1909DOI: 10.5194/cp-10-887-2014OAI: oai:DiVA.org:polar-1909DiVA, id: diva2:810416
Note
ISI Document Delivery No.: AG4FL Times Cited: 12 Cited Reference Count: 85 Kindler, P. Guillevic, M. Baumgartner, M. Schwander, J. Landais, A. Leuenberger, M. Denmark (SNF); Belgium (FNRS-CFB); France (IPEV); France (INSU/CNRS); France (ANR NEEM); Germany (AWI); Iceland (RannIs); Japan (MEXT); Sweden (SPRS); Switzerland (SNF); USA (NSF); Swiss National Science Foundation [200020-135152] We thank Peter Nyfeler and Hanspeter Moret for their helpful assistance during the measurements in the laboratory. The manuscript gained considerably by in depth comments given by two reviewers. This work is a contribution to the NGRIP ice core project, which is directed and organised by the Ice and Climate Research Group at the Niels Bohr Institute, University of Copenhagen. It is being supported by funding agencies in Denmark (SNF), Belgium (FNRS-CFB), France (IPEV, INSU/CNRS and ANR NEEM), Germany (AWI), Iceland (RannIs), Japan (MEXT), Sweden (SPRS), Switzerland (SNF) and the USA (NSF). This work was supported by the Swiss National Science Foundation contract no. 200020-135152. 12 Copernicus gesellschaft mbh Gottingen Geosciences, Multidisciplinary; Meteorology & Atmospheric Sciences
2015-05-072015-05-062017-12-04Bibliographically approved