Trans-Atlantic Equatorial (Active)

The Transatlantic Equatorial Cruise II (TRATLEQ II) was an interdisciplinary cruise focusing on upwelling in the tropical Atlantic. Main topics were the physical forcing of upwelling, its importance for biological production and plankton communities, associated chemical cycles, as well as the current system setting the background conditions for the downward carbon export. TRATLEQ II is the second cruise during which an integral approach of physical, chemical, bio-geochemical and biological measurements was applied, extending over the whole equatorial section from the eastern to the western boundary. A general aim of the of this research is to assess the status of the southeast and equatorial Atlantic marine ecosystem, to identify its physical drivers and the impact of climate variability and change. A central question was which role does circulation and mixing play for the development of phytoplankton and zooplankton communities and specifically how variable (regionally and seasonally) is the export flux of carbon to mesopelagic and bathypelagic depths associated with particle flux and diel vertical zooplankton migration.