Short Cruise Report, RV Maria S. Merian, cruise MSM-38, Cadiz – St. John's, May 07th – Jun 05th 2014

Abstract

Physical oceanographic measurements conducted during cruise MSM-38 were carried out in the framework of the Cluster of Excellence “Marum”, sub-project OC1, funded by the German Science Foundation (DFG). They further contributed to the cooperative research project “RACE”, sub-project 1.2, funded by the Federal Ministry of Education and Research (BMBF), and the DFG-funded project “FLEPVAR”. The primary objectives of cruise MSM-38 were: 1) To install and exchange longterm deep-sea observatories consisting of moorings in the Deep Western Boundary Current (DWBC) east of Flemish Cap at 47°N, in Flemish Pass, and along the western flank of the Mid-Atlantic Ridge (MAR). All moorings serve to measure the velocity structure and temperature and salinity of different components of North Atlantic Deep Water (NADW) as well as of the North Atlantic Current (NAC) and the Labrador Current (LC), respectively. 2) To service echo-sounders equipped with pressure sensors (PIES) installed at the sea bottom and to retrieve recorded data from the deployment period 2013-2014. 3) To analyze the strength and variability in the strength of the exported NADW in relation to the variations in the strength of the NAC in the Newfoundland Basin during 2013-2014. 4) To infer the main pathways of the NADW components and the NAC in the open subpolar North Atlantic and the strength of the subpolar gyre as it crosses the MAR. 5) To estimate the export of deep water towards the subtropics within the boundary current around Flemish Cap and via Flemish Pass, and to identify the water mass characteristics and respective changes on interannual time scales. 6) To assess the importance of the NAC and the deep water pathways for the lateral propagation of heat and freshwater anomalies