Publication Date:
2015-09-26
Description:
Antarctic ice-core data reveal that the atmosphere experienced abrupt centennial increases in CO2 concentration during the last deglaciation (~18 thousand to 11 thousand years ago). Establishing the role of ocean circulation in these changes requires high-resolution, accurately dated marine records. Here, we report radiocarbon data from uranium-thorium-dated deep-sea corals in the Equatorial Atlantic and Drake Passage over the past 25,000 years. Two major deglacial radiocarbon shifts occurred in phase with centennial atmospheric CO2 rises at 14.8 thousand and 11.7 thousand years ago. We interpret these radiocarbon-enriched signals to represent two short-lived (less than 500 years) "overshoot" events, with Atlantic meridional overturning stronger than that of the modern era. These results provide compelling evidence for a close coupling of ocean circulation and centennial climate events during the last deglaciation.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Chen, Tianyu -- Robinson, Laura F -- Burke, Andrea -- Southon, John -- Spooner, Peter -- Morris, Paul J -- Ng, Hong Chin -- New York, N.Y. -- Science. 2015 Sep 25;349(6255):1537-41. doi: 10.1126/science.aac6159.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Bristol Isotope Group, School of Earth Sciences, University of Bristol, Bristol, UK. tc14502@bristol.ac.uk. ; Bristol Isotope Group, School of Earth Sciences, University of Bristol, Bristol, UK. ; Department of Earth and Environmental Sciences, University of St Andrews, St. Andrews, UK. ; School of Physical Sciences, University of California, Irvine, Irvine, CA, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26404835" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Anthozoa/*chemistry
;
Atmosphere/*chemistry
;
Climate
;
*Global Warming
;
*Ice Cover
;
Oceans and Seas
;
Radiometric Dating
;
Thorium/analysis
;
Uranium/analysis
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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