Plattform Platform	Reise-Nr. Cruise-No.	Zeitraum Period	Projekt Project	Arbeitsgebiet Working area
Meteor	M189	16.04.2023 - 13.05.2023	TRIATLAS BANINO	SE Atlantic (Limit 20?W)

Fahrtleiter Chief Scientist	Institut Institute	Auslaufhafen Port of departure	Einlaufhafen Port of return	Stationskarte Station map	Schiffsroute Trackchart
Dengler Marcus	Helmholtz Centre for Ocean Research Kiel (GEOMAR)	Walvis Bay	Walvis Bay

Ziel der Reise / Objectives of Cruise:

The objective of the physical - biogeochemical measurement program on R/V Meteor cruise M189 was to measure the variability of the circulation and the coastal upwelling off Angola and Namibia. We focused on studying processes relevant to coastal upwelling, greenhouse gas production and emission, and biological productivity. Physical processes include oceanic forcing by the wind, the role of tide-generated internal waves and the turbulent mixing they cause, the role of freshwater inputs, and dynamic processes associated with the Angola-Benguela Front. The projects related to the cruise are the BMBF collaborative project "Benguela Ni?os: Physical processes and long-period variability (BANINO)" and the EU collaborative project "Tropical and South Atlantic climate-based marine ecosystem predictions for sustainable management (TRIATLAS)". Within BANINO we want to further extend the ocean observing system off the coast of Southwest Africa to measure and understand the variability of coastal upwelling on time scales from weeks to decades. In TRIATLAS, we are studying the current state of the ecosystem in the Southern and tropical Atlantic to better predict future changes. The work programme included servicing of moorings, hydrographic and velocity sections, an upwelling process studies with high-resolution sampling of hydrography, turbulence, biogeochemical parameters and autonomous measurements by ocean gliders. Additionally, continuous sampling of velocity in the upper water column and trace gas concentrations, temperature and salinity in the surface waters was carried out. Long-term oceanographic moorings measuring the variability of the eastern boundary circulation and hydrography are installed at 11?S and at 23?S in a water depth of 1500m and 100m, respectively. These moorings were serviced and reinstalled at the same position. Hydrographic sections (CTD/O2) and water samples were taken along 5 predominately zonal sections at 6?S, 11?S, 16?S, 20?S and 23?S and along a meridional section curring through a mesoscale cyclonic eddy in the Angola-Benguela frontal region at approximately 10.5?E . Parameters measured by sensors attached to the CTD-rosette include temperature, salinity, pressure, chlorophyll, turbidity, nitrate and particle detection using an underwater vision profiler. All CTD/O2 stations were accompanied by microstructure measurements to sample the strength of ocean turbulence in the upper water column. Water samples were take for the analysis of a variety of parameters including salinity, oxygen, nutrients (NH4+, NO3-, NO2-, PO34-, SiO2), trace gases (N2O), Sulfur (SO3), microbial abundances and single cell activity. A 4-day-long upwelling process study was carried out at 11?S. For this experiment, short-term moorings measuring velocity and hydrography were installed along a section perpendicular to bathymetry and three ocean gliders were deployed sampling hydrography, turbidity, oxygen and chlorophyll. Additionally, the gliders were carrying sensor package to sample nitrate, turbulence or particles using an underwater vision profiler. Repeated high-resolution profiles of turbulence and hydrography across the continental slope and shelf were taken along the section.

Messungen / Measurements

Verankerungen / Moorings