Building an operational and consistent oxygen dataset at the Coriolis DAC

Oxygen, measured using optical sensors, was the first biogeochemical parameter recorded by Argo floats.  The Argo program, now renamed OneArgo to take account of the ocean's biogeochemical (BGC) and deep components, now counts over 300,000 dissolved oxygen concentration profiles. This number of profiles makes the OneArgo program a key player in characterizing the biogeochemical state of the ocean.

 

Among the biogeochemical parameters on floats, endorsed by the International Oceanographic Commission (IOC), oxygen can be used to quantify, for example, the Net Community Production and when monitored at large scales, it helps in understanding the extent of the Oxygen Minimum Zone (OMZ) and the deoxygenation of the ocean.   Moreover, it is widely used in the calibration processes of other key parameters (Maurer et al., 2021) measured on floats such as the nitrate concentration and pH. 

 

OneArgo is built around autonomous robots, which implies specific constraints on data processing (Qualification, Validation... ) despite efforts to recover floats, post-deployment calibration to enhance sensor characterization and data quality remains rare. We would like to present the work lead in the European Data Assembly Center (DAC) Coriolis, in order to provide an operationally and consistent dissolved oxygen concentration profiles dataset, addressing Real Time (RT) and Delayed Mode (DM) processing for a wide range of sensors and float technologies.