Publication Date:
2006-08-26
Description:
We report atmospheric methane carbon isotope ratios (delta13CH4) from the Western Greenland ice margin spanning the Younger Dryas-to-Preboreal (YD-PB) transition. Over the recorded approximately 800 years, delta13CH4 was around -46 per mil (per thousand); that is, approximately 1 per thousand higher than in the modern atmosphere and approximately 5.5 per thousand higher than would be expected from budgets without 13C-rich anthropogenic emissions. This requires higher natural 13C-rich emissions or stronger sink fractionation than conventionally assumed. Constant delta13CH4 during the rise in methane concentration at the YD-PB transition is consistent with additional emissions from tropical wetlands, or aerobic plant CH4 production, or with a multisource scenario. A marine clathrate source is unlikely.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Schaefer, Hinrich -- Whiticar, Michael J -- Brook, Edward J -- Petrenko, Vasilii V -- Ferretti, Dominic F -- Severinghaus, Jeffrey P -- New York, N.Y. -- Science. 2006 Aug 25;313(5790):1109-12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉School of Earth and Ocean Sciences, University of Victoria, Post Office Box 3055, V8W 3P6, Canada. schaefeh@geo.oregonstate.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16931759" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
*Atmosphere
;
Bacteria/metabolism
;
Carbon Isotopes/analysis
;
*Climate
;
*Ecosystem
;
Environment
;
Greenland
;
Ice/*analysis
;
Methane/*analysis/metabolism
;
Plants/metabolism
;
Time
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
