Marine biogeochemists, physical oceanographers, and mooring engineers came together in Edinburgh on 20th February 2026 for the first workshop of its kind. The focus was biogeochemical sensors, and specifically whether the mooring arrays that monitor the Atlantic Meridional Overturning Circulation (AMOC) could also carry them. If so, these arrays could track ocean carbon, oxygen, and nutrients alongside their existing physical measurements.
The workshop was convened by Pete Brown (National Oceanography Centre) and Eleanor Frajka-Williams (Universität Hamburg). It drew 48 participants from 22 institutions across Europe and North America. The timing was deliberate: the concurrent Ocean Sciences Meeting 2026 in nearby Glasgow meant the international AMOC community was already in the UK, so the workshop made the most of that opportunity.
AMOC mooring arrays such as RAPID and OSNAP have measured the physics of ocean circulation (temperature, salinity, and velocity) with remarkable precision for over the last two decades. However, these same arrays have measured biogeochemistry far less consistently, even though carbon, oxygen, and nutrient concentrations shape the ocean’s role as both a climate regulator and a driver of marine ecosystems.
Presentations throughout the day built a compelling case. Biogeochemical sensors, participants argued, are no longer simply a nice-to-have addition to transport moorings. Instead, they are becoming a scientific necessity
Findings presented included evidence that carbon transport estimates based on temperature and salinity alone can carry significant biases (building on the work around circulation-driven variability in Atlantic anthropogenic carbon transport), and new results linking sea-ice variability in the Arctic to the efficiency of the ocean’s biological carbon pump, drawing on continuous mooring observations in Fram Strait.
Breakout discussions in the afternoon converged on a striking degree of consensus. Chief among the recommendations: dissolved oxygen sensors, a well-established type of biogeochemical sensor, are now mature, reliable, and affordable enough to be deployed as standard equipment. In other words, they should be as routine on every transport mooring array as temperature and salinity sensors already are.
Hilary Palevsky (Boston College), who moderated one of the workshop’s breakout groups, summed up the shift in thinking:
“We are now at the point where, in the same way you would never deploy a temperature sensor without salinity, we are ready to make a transition, that oxygen is just an expected variable that we would put on our transport mooring arrays.”
Participants also raised a note of caution. Before any existing mooring arrays are reduced further, they argued, biogeochemical observing system simulation experiments (OSSEs) need to properly assess what scientific value would be lost. The workshop’s closing remark was simple: don’t descope until the science tells us what we’d be giving up.
A full proceedings report from the workshop is now available. It documents all presentations and discussions, and can be read via Zenodo: Report on Workshop on ‘Next Generation Ocean Observing: Biogeochemical Sensors on Transport Mooring Arrays’.
The workshop’s outputs will feed directly into EPOC’s ongoing assessment of biogeochemical observing on AMOC transport arrays, carried out under Work Package 5. As a result, this work will help shape the observing system recommendations EPOC delivers to the wider ocean science community.