WAST DREDGE

WAST DREDGE: Recovery of two sediment trap systems at station WAST (Western Arabian Sea Trap) in the western Arabian Sea with RV SONNE (SO 302)

The Arabian Sea is a major oceanic nitrogen sink (up to 30%) due to suboxic/anoxic conditions in the oxygen minimum zone (OMZ). Long-term sediment trap investigations and first results of the research cruise M 74/1 suggest that major changes, probably due to the impact from climate change, on the carbon and nitrogen cycle have taken place during the last 25-30 years in the Arabian Sea. Moreover, recent investigations have shown that the pathways of the carbon and nitrogen cycle are more numerous and complex than thought previously. Sediment traps which were deployed at two locations at station WAST (Western Arabian Sea Trap) are intended to be recovered (dredged). Flux data and particle composition from sediment traps will be compared to the unique long-term data set available from the 1980s and 1990s and will provide reliable estimates of the changes in particle fluxes during three decades of global change in climate and material fluxes. Due to the various feedback mechanisms of the carbon and nitrogen cycle, they can both react to climatic and environmental change at short time scales and in turn influence the climate. Thus, the recovered samples also serve as improvement on climate models and predictions.

Project duration: 2023-2026

Information about the project: Dr. Niko Lahajnar, Dr. Birgit Gaye