Objective
The intergyre exchange of intermediate and deep waters in the North Atlantic Ocean between the subpolar and subtropical gyres will be determined in a joint effort of scientists of 5 oceanographic institutions from Russia, Germany, United Kingdom and Spain. Working at a full-depth meridional hydrographic section with a Russian research vessel in the North Atlantic Ocean, data will be collected to describe the thermohaline structure of the subpolar and subtropical gyres before the start of the cooling season, to inspect the spatial variability of the properties of the Deep Boundary Current System and to determine the pathways and the transformation rates of the Labrador Sea Water. The specific objectives of the project are:
to detail the present thermohaline structure of the North Atlantic Ocean;
to determine the rates of exchange for heat, salt and freshwater between the subpolar and subtropical gyres in the North Atlantic Ocean and to evaluate the transport of these properties within (internal circulation) and into the subpolar gyre;
to determine the large-scale thermohaline forced circulation and its interaction with the observed atmospheric forcing fields;
to estimate the long-term changes of the thermohaline structure and circulation of the North Atlantic Ocean.
The data will contribute to the ACCE / WOCE field programme, which is a World Climate Research Programme, called the Atlantic Climate Change Experiment, ACCE, joined with the North Atlantic Intensive Observation Period of the World Ocean Circulation Experiment, WOCE. It will provide the participants of the project with access to the observational database of the ACCE / WOCE experiment. Together with own data sets of the project participants, the afore-mentioned data will ensure a thorough description of the long-term changes of the North Atlantic thermohaline structure and time variability of the Meridional Overturning Circulation and the subpolar-subtropical intergyre exchange. The modelling activity within the project will quantify the relation between the variability of the thermohaline structure, the ocean circulation and the atmosphere forcing on longer time-scales.
This project will provide estimates of the cross-gyre transports of heat and freshwater between the subpolar and subtropical gyre during the ACCE / WOCE experiment and put them into perspective using other earlier data sets. It will also evaluate the phase relationship between the thermohaline forcing of the subpolar gyre and the observed changes in the intermediate and deep parts of the north-western Atlantic Ocean. It will identify areas of high and low spatial variability of the hydrographic fields and will provide estimates of the variability across the boundary current regimes South of Greenland, East of Newfoundland and South of the Grand Banks.
Call for proposal
Data not availableFunding Scheme
Data not availableCoordinator
20305 Hamburg
Germany