Toward Eddy Covariance CO2 Flux Measurement Capability on an Ocean Buoy

Direct air-sea CO₂ flux measurements using eddy covariance (EC) can be used to evaluate and improve ocean-atmosphere gas exchange parameterizations in global models. While EC CO₂ fluxes from research vessels have improved over the last 20 years, existing data sets are of limited duration, and significant technical challenges remain, such as air flow distortion about ships. An alternative is to use moored platforms such as ocean buoys that could enable longer deployments and are less affected by flow distortion. For CO₂, major hurdles in buoy-based EC flux measurements include sea spray effects on gas analyzer performance, significant power limitations, and sensitivity of commercially available infrared gas analyzers to platform motion. We present preliminary results from a collaborative effort to develop a robust, low-power EC air-sea CO₂ flux system that can be deployed on buoys.