Autonomous measurements of the marine carbon cycle in the North Sea

The North Sea helps to mitigate the impact of human CO₂ emissions on Earth’s climate by naturally absorbing CO₂ from the air and transporting it into the adjacent deep Atlantic Ocean. This CO₂ uptake is driven by a complex web of processes including seasonal growth and decay of plankton – which also sustains important fisheries – river water inputs, and chemical exchange between the water column and seafloor sediments.

The newly funded project will support development of RoboDock. RoboDock is an offshore platform that will serve as a recharge station and base from which an uncrewed surface vehicle (USV, pictured) and other drones can operate and communicate with a land-based control team. “After rigorous testing and validation in the laboratory, we will deploy a suite of autonomous biogeochemical sensors on the USV based at RoboDock,” said Dr Matthew Humphreys, scientist in the Department of Ocean Systems at NIOZ. “These sensors will measure key properties of the seawater CO₂ system wherever the USV travels, including waters within and around offshore wind farms. With the data, we will investigate what drives small-scale variability in marine carbon and nutrient cycles and how this may be influenced by human activities. This work will improve our understanding of the likely consequences of ongoing offshore infrastructure development and global environmental change.”

"To understand how the role of the North Sea may be influenced by stressors both global (e.g. warming, increasing CO₂) and local (e.g. construction, trawling), we must conduct high-quality measurements of the changing seawater system. The measurements must be high-resolution, because the critical processes operate over short length- and time-scales. The measurements must be sustained, in order to capture the full range of conditions experienced by this highly variable system. These requirements cannot be easily met by traditional research expeditions due to staff, time and cost constraints, but the autonomous sensor technology planned for the RoboDock project is now stepping up to fill this capability gap."

NIOZ’s contribution to RoboDock will be led by Dr Matthew Humphreys and Prof Dr Gert-Jan Reichart of the Department of Ocean Systems.