Our group studies how interactions between the ocean and its boundaries facilitate the chemical composition of the ocean, and uses variability in seawater chemistry to quantify the function of the ocean as a carbon pump.

The ocean’s capacity to mitigate climate change is dependent on biological and geochemical processes. We seek to improve our understanding and ability to quantify variability in seawater chemistry to better assess the marine carbon cycle. We use water chemistry analyses on samples we collect from cruises in different ocean basins to quantify biogeochemical processes, focusing on major elements (calcium, strontium, lithium) and the concentrations of transition metals in seawater as indicators. As different groups of organisms tend to incorporate constituents into their skeletons in characteristic ratios, we are able to quantify their abundance in the ocean from the variability in seawater concentrations of the main elements they use for building their skeletons, and thus assess the impact of climate change on these organisms.

Ocean boundaries (e.g. sediment, river, hydrothermal vents, dust) impact the supply and removal of various elements in the ocean. Along these boundaries, we use sediment analyses to identify and quantify the mechanisms that control the formation of authigenic minerals as feedback mechanisms that restrain changes in the chemical composition of the ocean.