Observed Transport Variations of the Main Upper AMOC Branch in the North Atlantic

In the western North Atlantic, warm and saline water is brought by the North Atlantic Current (NAC) from the subtropics into the subpolar gyre and thereby forming the the main upper branch of the AMOC. We present geostrophic velocity measurements between 2006 and 2015 from inverted echo sounders at the gateway between western and eastern Atlantic. We further exploit the correlation between the measured transports and the geostrophic velocity from altimeter data and extend the time series of NAC transports back to 1992. We will discuss long-term trends and variability of baroclinic and barotropic components on different time scales. The variability of the NAC at 47°N in the Newfoundland Basin will also be discussed.