HR: 15:45h
AN: OS52L-06    [PDF]
TI: Monitoring The Deep Branch Of The Atlantic Meridional Overturning Circulation At $16^\circ$ N
AU: * Kanzow, T
EM: tkanzow@ifm.uni-kiel.de
AF: Institut fuer Meereskunde Kiel, Duesternbrooker Weg 20, Kiel, 24105 Germany
AU: Send, U
EM: usend@ifm.uni-kiel.de
AF: Institut fuer Meereskunde Kiel, Duesternbrooker Weg 20, Kiel, 24105 Germany
AU: Zenk, W
EM: wzenk@ifm.uni-kiel.de
AF: Institut fuer Meereskunde Kiel, Duesternbrooker Weg 20, Kiel, 24105 Germany
AU: Rhein, M
EM: mrhein@theo.physik.uni-bremen.de
AF: Institut fuer Umweltphysik, Universitaet Bremen Postfach 330 440, Bremen, 28334 Germany
AB: Fluctuations of the meridional overturning circulation (MOC) are thought to have an important impact on the climate system. Such fluctuations are common features in models but until today observational evidence is missing. Here the Feb 2000 to Jun 2003 results from the ongoing Meridional Overturning Variability Experiment (MOVE, observational German CLIVAR project) will be presented. The scientific aim of MOVE is to acquire multi-year time series of variations of the meridional transport and of the hydrographic conditions of the NADW. The experiment strategy makes use of horizontally integrating geostrophic end-point moorings, measuring temperature, salinity and bottom pressure. This allows for basin scale monitoring of transport fluctuations with a very limited number of moorings. The moored MOVE array is located at $16^\circ$ N, monitoring transports through the 1000 km section between the Lesser Antilles and the Mid-Atlantic Ridge.The results include rapidly changing hydrographic conditions at the mooring locations, indications of an interior recirculation of the southward DWBC and a large temporal variability of the meridional NADW transport, at times exceeding 10 Sv on a monthly scale. As a reference, simultaneously acquired moored direct current measurements along the section from the joint MOVE/GAGE (Guyana Abyssal Gyre Experiment, WHOI) effort are used. The observed variability is then interpreted in the context of model results. Finally, to demonstrate its potential as well as to point out deficiencies, the monitoring array is simulated using model data.
DE: 4512 Currents
DE: 4532 General circulation
DE: 4576 Western boundary currents
SC: Ocean Sciences [OS]
MN: 2004 Ocean Sciences Meeting