Cruises LEFE CYBER

Strasse is the first cruise of the international program SPURS of the study of the salinity maximum of the North Atlantic subtropical gyre. It took place on the NO Thalassa from August 161 to September 13 2012, and contributes to SPURS investigations by measuring air-sea fluxes and measuring the upper ocean physical properties, including surface waves. This was done from the ship during CTD stations, scamp profiles, towing the undulating vessel Scanfish or sampling the upper meter of the ocean through the SSP, and by various continuously recording instruments. The cruise also allowed the operation of autonomous vehicles: gliders, instrumented drifters, autonomous profiler ASIP, autonomous ship Vaïmos and trimaran Ocarina. The in situ data will also be used to better understand the data obtained from remote instruments on board the satellites SMOS and Aquarius. The isotopomeric composition of water vapour was also measured as well as solid aerosol deposits. The cruise was also the opportunity to measure sea water optical properties and to investigate some components of the upper ocean bio-geochemical cycles, in particular through chemical measurements, bio-optical measurements and cultures. During the cruise, 94 CTD profiles, 80 valid scamp profiles and over 60 optical package profiles were collected, and more than 200 hours of scanfish tow, 10 days of ASIP profiles, 200 hours of ocarina, 10 hours of SSP as well as three days of good Vaïmos data were acquired. Ari-sea fluxes and sea waves will be estimated almost continuously in different ways. A meso-scale survey was carried to investigate a high salinity tongue extending in the midst of the subtropical gyre, separating an anticyclonic region of strong currents to its southwest from a more quiescent region to its north-east. Four 3-days long sub-meso scale stations/surveys were then done to investigate different dynamical regimes and understand how surface properties evolve: one just to the north-east of the salty tongue, one in the core it, one to its southwestern flank, and one in the quiescent low-salinity region in the north-east.