Derivation of an age scale for the Law Dome core - ice cores taken between 1987 and 1993
Entry ID:
DSS_age_scale
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Summary
Abstract:
Records of methane, and oxygen isotopes (ice and air) for Law Dome DSS (Dome Summit South) core through the last deglaciation (9000-19000 before present). Data are obtained from the entire DSS core, collected between late 1987 and early 1993. Data comprise air composition measurements (d18Oair (per mille) and methane composition (ppbv)) and water isotope data (per mille) from the Law Dome core ... with age scale matched to the GRIP (Greenland) ice core. Default age scale (yr BP, 1950) gives best age scale - LDmin age scale gives a minimum age limiting case that is not the preferred dating.
Supporting information is provided in a pdf document available both in the dataset for download, and the online Science site.
This work was completed as part of ASAC project 757.
The work is also related to the Greenland Ice Core Project (GRIP), and the Greenland Ice Sheet Project Two (GISP2).
The last deglaciation was marked by large, hemispheric, millennial-scale climate variations: the Bølling-Allerød and Younger Dryas periods in the north, and the Antarctic Cold Reversal in the south. A chronology from the high-accumulation Law Dome East Antarctic ice core constrains the relative timing of these two events and provides strong evidence that the cooling at the start of the Antarctic Cold Reversal did not follow the abrupt warming during the northern Bølling transition around 14,500 years ago. This result suggests that southern changes are not a direct response to abrupt changes in North Atlantic thermohaline circulation, as is assumed in the conventional picture of a hemispheric temperature seesaw.
Public Summary from project 757:
Prediction of future climate change requires knowledge of past changes. Polar snow forms an archive of environmental conditions that is accessible by drilling and analysing ice cores. This project uses ice core data to reconstruct and study records, including past temperature and atmospheric composition, to improve understanding of the climate system.
The fields in this dataset are:
(Note: Ages are all BP (1950); the two scenarios only give identical gas-ages at tie-points.)
Sample Mid Depth (metres)
Sample Length (metres)
Delta 18O air (ppt)
Sample Mid Gas Age (Default)
Delta Age (Default) (years)
Sample Mid Gas Age (LDmin)
Delta Age (LDmin) (years)
CH4 (ppbv)
Depth (metres)
Age (Default)
Age (LDmin)
Delta 18 O (ppt) 
Related URL
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Description:
Download point for the data
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Geographic Coverage
(Click for Interactive Map)
Spatial coordinates
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N: -66.77
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S: -66.77
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E: 112.81
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W: 112.81
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Min Altitude:
1370 M
Max Altitude:
1370 M
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Min Depth:
1105.282 M
Max Depth:
1133.622 M
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Parent DIF
This data set description is a member of a collection. The
collection is described in
ASAC_757
Temporal Coverage
Start Date:
1987-12-01
Stop Date:
2002-08-02
Paleo Temporal Coverage
Paleo Start Date:
19000 YBP
Paleo Stop Date:
9000 YBP
Chrono Unit:
Quality
Data have been published, and are considered good. Stop date provided in temporal coverage is the date of publication.
Access Constraints
The dataset is available from the url's given below. The pdf document is available both on an external website, and as part of the download with the data itself.
Data Set Progress
COMPLETE
Distribution
Distribution Media:
HTTP
Distribution Size:
290 kb
Distribution Format:
csv
Fees:
free
Personnel
Role:
INVESTIGATOR
Phone:
+61 3 6226 2954
Fax:
+61 3 6226 2902
Email:
vin.morgan at utas.edu.au
Contact Address:
Grosvenor St
Antarctic CRC, University of Tasmania
City:
Sandy Bay
Province or State:
Tasmania
Postal Code:
7005
Country:
Australia
Role:
DIF AUTHOR
Phone:
+61 3 6232 3244
Fax:
+61 3 6232 3351
Email:
dave.connell at aad.gov.au
Contact Address:
Australian Antarctic Division
203 Channel Highway
City:
Kingston
Province or State:
Tasmania
Postal Code:
7050
Country:
Australia
Role:
INVESTIGATOR
Role:
TECHNICAL CONTACT
Phone:
+61 3 6226 2981
Email:
tas.van.ommen at utas.edu.au
Contact Address:
Antarctic Climate and Ecosystems CRC
University of Tasmania
Grosvenor St
City:
Sandy Bay
Province or State:
Tasmania
Postal Code:
7005
Country:
Australia
Publications/References
Abshire, J., and 8 others. 2005. Geoscience Laser Altimeter System (GLAS) on the ICESat mission: on-orbit measurement performance. Geophysical Research Letters v. 32, L21S02, doi:10.1029/2005GL1024028. Brenner, A., and 11 others. 2003. Derivation of range and range distributions from laser pulse waveform analysis for surface elevations, roughness, slope, and vegetations heights, Algorithm ... Theoretical Basis Document (ATBD) v.4.1, available at http://www.csr.utexas.edu/glas/atbd.html.
DiMarzio, J. P., A. C. Brenner, and H. J. Zwally. 2004. Comparison of Envisat and ERS radar altimetry for ice Âsheet elevation change studies. ESA Envisat Sympsium, Salzburg, Austria, September 9, 2004.
Krabill, W., W. Abdalati, and 7 others. 2002. Aircraft laser altimetry measurement of elevation changes of the Greenland Ice Sheet: technique and accuracy assessment. J. Geodynamics 34, 357-376.
Shuman, C., J. Zwally, B. Schutz, A. Brenner, J. DiMarzio, V. Schuedo, and H. Fricker. 2006. ICESat Antarctic elevation data: preliminary precision and accuracy assessment. Geophysical Research Letters 33, L07501, doi:10.1029/2005GL025227.
Zwally, H. J., A. C. Brenner, J. A. Major, T. V. Martin, and R. A. Bindschadler. 1990. Satellite radar altimetry over ice, Vol. 1. Processing and corrections of Seasat data over Greenland. NASA Reference Publication 1233.
Creation and Review Dates
DIF Creation Date:
2007-06-21
Last DIF Revision Date:
2012-05-14
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