Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model
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 circulati...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2007-01-01
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| Series: | Climate of the Past |
| Online Access: | http://www.clim-past.net/3/97/2007/cp-3-97-2007.pdf |
| _version_ | 1818618098019729408 |
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| author | M. Schulz M. Schulz M. Prange M. Prange A. Klocker A. Klocker |
| author_facet | M. Schulz M. Schulz M. Prange M. Prange A. Klocker A. Klocker |
| author_sort | M. Schulz |
| collection | DOAJ |
| description | 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. |
| first_indexed | 2024-12-16T17:16:11Z |
| format | Article |
| id | doaj.art-8a0989ca52a540378621992510bebd30 |
| institution | Directory Open Access Journal |
| issn | 1814-9324 1814-9332 |
| language | English |
| last_indexed | 2024-12-16T17:16:11Z |
| publishDate | 2007-01-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Climate of the Past |
| spelling | doaj.art-8a0989ca52a540378621992510bebd302022-12-21T22:23:17ZengCopernicus PublicationsClimate of the Past1814-93241814-93322007-01-013197107Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate modelM. SchulzM. SchulzM. PrangeM. PrangeA. KlockerA. KlockerUsing 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.http://www.clim-past.net/3/97/2007/cp-3-97-2007.pdf |
| spellingShingle | M. Schulz M. Schulz M. Prange M. Prange A. Klocker A. Klocker Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model Climate of the Past |
| title | Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model |
| title_full | Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model |
| title_fullStr | Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model |
| title_full_unstemmed | Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model |
| title_short | Low-frequency oscillations of the Atlantic Ocean meridional overturning circulation in a coupled climate model |
| title_sort | low frequency oscillations of the atlantic ocean meridional overturning circulation in a coupled climate model |
| url | http://www.clim-past.net/3/97/2007/cp-3-97-2007.pdf |
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