Atlantic Equatorial Upwelling Study 2011 - Cruise No. MSM18/3 - June 22 - July 21, 2011 - Mindelo (Cape Verde) - Libreville (Gabon) (English)

MERIAN cruise MSM18/3 to the tropical Atlantic was a joint activity of the Kiel Collaborative Research Centre SFB 754 ("Climate - Biogeochemistry Interactions in the Tropical Ocean") and the collaborative BMBF project SOPRAN II ("Surface Ocean Processes in the Anthropocene"). For the SFB 754, this cruise represented the final Atlantic field campaign of the first funding period 2008- 2011. The main SFB 754 scientific foci of this cruise were: (-) Third occupation of 23°W section which has been defined as standard section for detection of temporal variability scales and trends of the oxygen inventory (sub-project A4); (-) Redox sensitivity of biological N2 fixation (sub-project B3). The regional focus in the Atlantic Ocean of the second funding phase of SOPRAN was placed on the equatorial upwelling. Cruise MSM18/3 represented the central (and only major) Atlantic field activity of SOPRAN II and had the following scientific sub-projects: (-) The contribution of physical processes to the emission of trace gases in upwelling areas of the tropical Atlantic Ocean: A N2O case study (sub-project IG02) (-) Air-sea fluxes of CO2 and O2 in the equatorial and subtropical Atlantic: Observing variability on diel to interannual time scales (sub-project IG05). (-) Atmospheric dust deposition to the ocean: Ecosystem effects of dust deposition on phytoplankton productivity and nitrogen fixation (sub-project IG06); (-) The influence of surface ocean processes on OVOCs and DMS in the atmosphere (sub-project IG07); (-) Sources and sinks of iodinated and brominated compounds in the tropical and equatorial Atlantic (sub-project IG10) (-) Aerosol-Ocean-Interaction: Import of dust into the ocean and export of organic matter from the ocean (sub-project IFT01); (-) Upwelling velocities off Mauritania and at the equatorial Eastern (sub-project UB02); (-) Quantitative studies of marine halogen release (sub-project UHE02).