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	<journal>
		<journal_title>Climate of the Past</journal_title>
		<journal_url>www.clim-past.net</journal_url>
		<issn>1814-9324</issn>
		<eissn>1814-9332</eissn>
		<volume_number>3</volume_number>
		<issue_number>1</issue_number>
		<publication_year>2007</publication_year>
	</journal>
	<doi>10.5194/cp-3-97-2007</doi>
	<article_url>http://www.clim-past.net/3/97/2007/</article_url>
	<abstract_html>http://www.clim-past.net/3/97/2007/cp-3-97-2007.html</abstract_html>
	<fulltext_pdf>http://www.clim-past.net/3/97/2007/cp-3-97-2007.pdf</fulltext_pdf>
	<start_page>97</start_page>
	<end_page>107</end_page>
	<publication_date>2007-02-07</publication_date>
	<article_title content_type="html">Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model</article_title>
	<authors>
		<author numeration="1" affiliations="1,2">
			<name>M. Schulz</name>
			<email>mschulz@uni-bremen.de</email>
		</author>
		<author numeration="2" affiliations="1,2">
			<name>M. Prange</name>
		</author>
		<author numeration="3" affiliations="1,3">
			<name>A. Klocker</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Department of Geosciences, University of Bremen, Germany</affiliation>
		<affiliation numeration="2" content_type="html">DFG Research Center &quot;Ocean Margins&quot;, University of Bremen, Germany</affiliation>
		<affiliation numeration="3" content_type="html">now at: CSIRO Marine and Atmospheric Research, Hobart, Australia</affiliation>
	</affiliations>
	<abstract content_type="html">Using a 3-dimensional climate model of intermediate complexity we show that
the overturning circulation of the Atlantic Ocean can vary at
multicentennial-to-millennial timescales for modern boundary conditions. A
continuous freshwater perturbation in the Labrador Sea pushes the
overturning circulation of the Atlantic Ocean into a bi-stable regime,
characterized by phases of active and inactive deep-water formation in the
Labrador Sea. In contrast, deep-water formation in the Nordic Seas is active
during all phases of the oscillations. The actual timing of the transitions
between the two circulation states occurs randomly. The oscillations
constitute a 3-dimensional phenomenon and have to be distinguished from
low-frequency oscillations seen previously in 2-dimensional models of the
ocean. A conceptual model provides further insight into the essential
dynamics underlying the oscillations of the large-scale ocean circulation.
The model experiments indicate that the coupled climate system can exhibit
unforced climate variability at multicentennial-to-millennial timescales
that may be of relevance for Holocene climate variations.</abstract>
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