Our main goal on day 2 (9.10.2024) was to learn how OAE minerals can be applied underwater in a way that they don’t immediately drift out of predefined plots. The video below shows olivine dispersal when delivered relatively quickly. Time is crucial because there will be 12 plots in the experiment and dive time is limited. The idea to deliver minerals frozen as slurry into a “tile” was tested as an alternative to just dispersing mineral powder. The frozen tile approach was not successful, however, as the tile melted too quickly and could not be deployed in time. We also tested pore water sampling, which worked really well, and we got first pore water pH and alkalinity measurements. These are important to inform what minerals we can finally use for the field experiment.

Benthic flux chambers will be used to determine alkalinity fluxes under different OAE conditions. Our test with a flux chamber was successful.

The weather was perfect on day 2, which showed us how much work we can get done on a day with little wind swell. Next up is setting up the 12 plots on which the study will be conducted.

Lennart Bach