| Summary: | 41 páginas, 19 figuras.-- Pascale Lherminier . et al.-- Merian Cruise N. 2, Leg. 1, Lisbon (Portugal) - Thorshavn (Faroes), May 21 to June 28, 2006 Cruise MSM02/1 is the third occurrence of the Ovide hydrological section that was performed in 2002 and 2004, as part of the CLIVAR programme under the name of A25. The Ovide Principal Investigator is Herlé Mercier. A Greenland-Portugal section was previously performed in 1997 under the leadership of S. Bacon (NOCS), slightly south of the Ovide path. The Ovide route crosses Reykjanes Ridge 300 miles north of Charlie-Gibbs Fracture Zone and runs through the West European Basin without having to sample on top of the complex Mid-Atlantic Ridge. The objective of this repeated hydrological section is to monitor the variability of water mass properties and main current transports in the basin, complementing the international observation array relevant for climate studies. The western part of the Ovide section is redundant with AR7E (called also A1) which was done on the odd years and will allow a better analysis of the inter annual variability. The hydrological section includes a hundred surface-bottom stations from coast to coast, collecting profiles of temperature, salinity, oxygen and currents. From the 28 bottles closed at various depth at each stations, samples of sea water are used for salinity and oxygen calibration, and for measurements of biogeochemical components, including tracers, isotopes, nutrients and carbon. From the thermal wind equations, geostrophic transports are deduced from temperature and salinity. Then, direct current observations, preferentially those measured by the ship ADCP, are used to constrain the velocity at the chosen reference level. This is particularly important in the Irminger Sea, where bottom currents are very energetic. This way, the contribution in heat and fresh water of the major currents crossed (mostly perpendicularly) by the Ovide line can be estimated. From north to south, the major currents are the East Greenland/Irminger ...
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