English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/61190
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Title

Heinrich event 1: an example of dynamical ice-sheet reaction to oceanic changes

AuthorsÁlvarez-Solas, J. ; Montoya, Marisa ; Ritz, Catherine; Ramstein, Gilles; Charbit, Sylvie; Dumas, Christophe; Nisanciogl, Kerim; Dokken, Trond; Ganopolski, Andrey
KeywordsClimatología
Heinrich events
Paleoclimatología
Issue Date29-Nov-2011
PublisherCopernicus Publications
CitationÁLVAREZ-SOLAS ,J., MONTOYA, M., RITZ, C., RAMSTEIN, G., CHARBIT, S., DUMAS, C., NISANCIOGLU, K., DOKKEN, T., GANOPOLSKI, A. (2011). Heinrich event 1: an example of dynamical ice-sheet reaction to oceanic changes. Climate of the Past, 7, 1297-1306.
AbstractHeinrich events, identified as enhanced ice-rafted detritus (IRD) in North Atlantic deep sea sediments (Heinrich, 1988; Hemming, 2004) have classically been attributed to Laurentide ice-sheet (LIS) instabilities (MacAyeal, 1993; Calov et al., 2002; Hulbe et al., 2004) and assumed to lead to important disruptions of the Atlantic meridional overturning circulation (AMOC) and North Atlantic deep water (NADW) formation. However, recent paleoclimate data have revealed that most of these events probably occurred after the AMOC had already slowed down or/and NADW largely collapsed, within about a thousand years (Hall et al., 2006; Hemming, 2004; Jonkers et al., 2010; Roche et al., 2004), implying that the initial AMOC reduction could not have been caused by the Heinrich events themselves. Here we propose an alternative driving mechanism, specifically for Heinrich event 1 (H1; 18 to 15 ka BP), by which North Atlantic ocean circulation changes are found to have strong impacts on LIS dynamics. By combining simulations with a coupled climate model and a three-dimensional ice sheet model, our study illustrates how reduced NADW and AMOC weakening lead to a subsurface warming in the Nordic and Labrador Seas resulting in rapid melting of the Hudson Strait and Labrador ice shelves. Lack of buttressing by the ice shelves implies a substantial ice-stream acceleration, enhanced ice-discharge and sea level rise, with peak values 500–1500 yr after the initial AMOC reduction. Our scenario modifies the previous paradigm of H1 by solving the paradox of its occurrence during a cold surface period, and highlights the importance of taking into account the effects of oceanic circulation on ice-sheets dynamics in order to elucidate the triggering mechanism of Heinrich events.
Publisher version (URL)http://dx.doi.org/10.5194/cp-7-1297-2011
URIhttp://hdl.handle.net/10261/61190
DOI10.5194/cp-7-1297-2011
Appears in Collections:(IGEO) Artículos
Files in This Item:
File Description SizeFormat 
cp-7-1297-2011.pdfPaper2,56 MBAdobe PDFThumbnail
View/Open
Supinfo_he1_CP_def.pdfSuplemento78,15 kBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.