Monitoring the integrated deep meridional flow in the tropical North Atlantic
The Atlantic meridional overturning circulation (MOC) is thought to have strong impact on climate.Here results from a pilot project to monitor fluctuations of the MOC in the tropical North Atlantic are presented. The backbone of the experiment design is an end point measurement method. One main aspect of this study comprises a technical performance assessment of the different measurement components (density,bottom pressure,current velocities) of the moored array. For the interpretation of the observed mean and time variable volume transports, comparisons to independent observational data and numerical model output have been carried out and spectral analysis as well as basic theoretical aspects of fluid dynamics have been applied. Rossby waves represent a major source of noise, which may mask the MOC signal. A verification of the experiment design using model simulations attest the transport signal observed to be moderately representative for MOC and meridional heat transport fluctuations. An eastward extension of the array into the eastern trough might lead to a drastic increase in the signal-to-noise ratio.