Predictability of the mid-latitude Atlantic meridional overturning circulation in a multi-model system

• Published in: Climate Dynamics
• Main Authors: Pohlmann, H., Smith, D. M., Balmaseda, M. A., Keenlyside, N. S., Masina, S., Matei, D., Muller, W. A., Rogel, P.
• Other Authors: Pohlmann, H.; Max-Planck-Institut fu ̈r Meteorologie, Smith, D. M.; Met Office Hadley Centre, Balmaseda, M. A.; ECMWF, Keenlyside, N. S.; Geophysical Institute and Bjerknes Centre, University of Bergen, Masina, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia, Matei, D.; Max-Planck-Institut fu ̈r Meteorologie, Muller, W. A.; Max-Planck-Institut fu ̈r Meteorologie, Rogel, P.; CERFACS, Max-Planck-Institut fu ̈r Meteorologie, Met Office Hadley Centre, ECMWF, Geophysical Institute and Bjerknes Centre, University of Bergen, Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia, CERFACS
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Verlag GMBH Germany 2013
• Subjects: Decadal prediction ???? Atlantic MOC ???? Predictability ???? Multi-model comparison; 01. Atmosphere::01.01. Atmosphere::01.01.02. Climate; 03. Hydrosphere::03.01. General::03.01.03. Global climate models; 03. Hydrosphere::03.03. Physical::03.03.03. Interannual-to-decadal ocean variability; Labrador Sea; North Atlantic; North Atlantic oscillation
• Online Access: http://hdl.handle.net/2122/8588; https://doi.org/10.1007/s00382-013-1663-6

Assessing the skill of the Atlantic meridional overturning circulation (AMOC) in decadal hindcasts (i.e. retrospective predictions) is hampered by a lack of obser- vations for verification. Models are therefore needed to reconstruct the historical AMOC variability. Here we show that ten recent oceanic syntheses provide a common signal of AMOC variability at 45°N, with an increase from the 1960s to the mid-1990s and a decrease thereafter although they disagree on the exact magnitude. This signal corre- lates with observed key processes such as the North Atlantic Oscillation, sub-polar gyre strength, Atlantic sea surface temperature dipole, and Labrador Sea convection that are thought to be related to the AMOC. Furthermore, we find potential predictability of the mid-latitude AMOC for the first 3–6 year means when we validate decadal hindcasts for the past 50 years against the multi-model signal. However, this predictability is not found in models driven only by external radiative changes, demonstrating the need for initialization of decadal climate predictions. Published 775-785 3.7. Dinamica del clima e dell'oceano JCR Journal restricted