Publication Date:
2015-06-13
Description:
Our current understanding of ocean-atmosphere-cryosphere interactions at ice-age terminations relies largely on assessments of the most recent (last) glacial-interglacial transition, Termination I (T-I). But the extent to which T-I is representative of previous terminations remains unclear. Testing the consistency of termination processes requires comparison of time series of critical climate parameters with detailed absolute and relative age control. However, such age control has been lacking for even the penultimate glacial termination (T-II), which culminated in a sea-level highstand during the last interglacial period that was several metres above present. Here we show that Heinrich Stadial 11 (HS11), a prominent North Atlantic cold episode, occurred between 135 +/- 1 and 130 +/- 2 thousand years ago and was linked with rapid sea-level rise during T-II. Our conclusions are based on new and existing data for T-II and the last interglacial that we collate onto a single, radiometrically constrained chronology. The HS11 cold episode punctuated T-II and coincided directly with a major deglacial meltwater pulse, which predominantly entered the North Atlantic Ocean and accounted for about 70 per cent of the glacial-interglacial sea-level rise. We conclude that, possibly in response to stronger insolation and CO2 forcing earlier in T-II, the relationship between climate and ice-volume changes differed fundamentally from that of T-I. In T-I, the major sea-level rise clearly post-dates Heinrich Stadial 1. We also find that HS11 coincided with sustained Antarctic warming, probably through a bipolar seesaw temperature response, and propose that this heat gain at high southern latitudes promoted Antarctic ice-sheet melting that fuelled the last interglacial sea-level peak.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Marino, G -- Rohling, E J -- Rodriguez-Sanz, L -- Grant, K M -- Heslop, D -- Roberts, A P -- Stanford, J D -- Yu, J -- England -- Nature. 2015 Jun 11;522(7555):197-201. doi: 10.1038/nature14499.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory 2601, Australia. ; 1] Research School of Earth Sciences, The Australian National University, Canberra, Australian Capital Territory 2601, Australia [2] Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton SO14 3ZH, UK. ; Department of Geography, Wallace Building, Swansea University, Singleton Park, Swansea SA2 8PP, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26062511" target="_blank"〉PubMed〈/a〉
Keywords:
Antarctic Regions
;
Aquatic Organisms/metabolism
;
Atlantic Ocean
;
Climate
;
Foraminifera/metabolism
;
History, Ancient
;
*Ice Cover
;
Mediterranean Region
;
Mediterranean Sea
;
Plankton/metabolism
;
Seawater/*analysis
;
Temperature
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
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