North Atlantic Circulation:RV Maria S Merian expedition completed

16.07.2009

What is the role of the North Atlantic Ocean in the earth´s climate? What effect does global warming have on oceanic circulation? To what degree is the ocean responsible for climate fluctuations? These and other questions concerned 21 scientists, technicians and students from Germany, England, Finland, France and Russia during a five-week expedition with the ice margin research vessel Maria S Merian in the North Atlantic between Canada, Greenland and Iceland.

Under the scientific leadership of Chief Scientist Professor Detlef Quadfasel from the KlimaCampus of the University of Hamburg, the group of marine researchers investigated the northern branch of the Atlantic overturning circulation, which plays a central role in the dynamics of the earth´s climate system.

During the Expedition MSM12-1 the Merian traveled nearly 5000 nautical miles. Valuable data were obtained on oceanic circulation at more than 200 positions. The three focal points were 1) the overflow of deep water from the nordic ocean through the Denmark Strait into the North Atlantic, 2) the mixing of this overflow with surrounding water masses and 3) the export of the deep water from the Labrador Sea.

Moorings at the ocean bottom, some of which have been maintained for over ten years, gave information about long-term changes in the circulation. Instruments were deployed from the ship in order to study the microstructure of the overflow and its mixing with the surrounding water. For this, a special microstructure probe of the Shirshov Institute for Oceanology in Kaliningrad was employed, which made it possible to obtain the first detailed survey of small-scale turbulence in water depths of more than 2500 m.

The successful research cruise was rounded off with a reception in Reykjavik. Among the guests were the Icelandic Foreign minister, several Ambassadors and colleagues from the Icelandic scientific community.

The scientific work was funded by the BMBF North Atlantic Project and the EU Project THOR (ThermoHaline Overturning – at Risk?) The operating costs of the
Maria S Merian were covered by the German Research Council and the German Federal Ministry of Education and Research.

The RV Maria S Merian, which has been in operation since 2006, is the most modern research vessel in Germany. The scientific, technical, logistical and financial coordination of its cruises is carried out by the "Control station Meteor/Merian" of the University of Hamburg. The ship is managed by Briese Schiffahrts GmbH & Co. KG. from Leer (Germany).

Further information on the science:

www.eu-thor.eu/Scientific-NEWS.609.0.html

Further information on the ship:

www.ifm.zmaw.de/de/leitstelle/reisen-des-fs-maria-s-merian/