Global Warming Research Today is a free monthly online journal that collates and summarizes the latest research about Global Warming, including details on causes, effects, impact, facts, myths, information.

Temporal variability of the Atlantic meridional overturning circulation at 26.5 degrees N.

Cunningham SA, Kanzow T, Rayner D, Baringer MO, Johns WE, Marotzke J, Longworth HR, Grant EM, Hirschi JJ, Beal LM, Meinen CS, Bryden HL

National Oceanography Centre, Empress Dock, Southampton SO14 3ZH, UK. scu@noc.soton.ac.uk

The vigor of Atlantic meridional overturning circulation (MOC) is thought to be vulnerable to global warming, but its short-term temporal variability is unknown so changes inferred from sparse observations on the decadal time scale of recent climate change are uncertain. We combine continuous measurements of the MOC (beginning in 2004) using the purposefully designed transatlantic Rapid Climate Change array of moored instruments deployed along 26.5 degrees N, with time series of Gulf Stream transport and surface-layer Ekman transport to quantify its intra-annual variability. The year-long average overturning is 18.7 +/- 5.6 sverdrups (Sv) (range: 4.0 to 34.9 Sv, where 1 Sv = a flow of ocean water of 10(6) cubic meters per second). Interannual changes in the overturning can be monitored with a resolution of 1.5 Sv.

Published 17 August 2007 in Science, 317(5840): 935-8.
Full-text of this article is available online (may require subscription).

© 2004-2008 Global Warming Research Today. All Rights Reserved.