Bridging the traceability gap: an empirical assessment of methodological links between EMODnet data and OBPS practices

Ocean observing produces quantities of data whose scientific and policy value is enhanced when information about collection methods and quality control is available. Links to the methods used to collect and process the data are essential to provide the necessary context. Yet, the linkage between in situ data repositories and formal method documentation remains limited. Starting in 2024, the Ocean Best Practices System (OBPS) and the Physics thematic pillar of the European Marine Observation and Data Network (EMODnet) initiated a collaborative effort to extend the EMODnet Physics metadata model to include such linkages, with OBPS providing access to ocean practice documentation. The goal is to link EMODnet data records to method descriptions using persistent identifiers (DOIs) assigned to methods in OBPS and referenced in EMODnet metadata. This paper assesses the state of these linkages and analyses the progress achieved, remaining gaps, and potential approaches for improvement. The approach was evaluated through engagement with EMODnet Physics data providers and the development of a dataset-linked method compendium. At the time of this assessment (June 2025 – January 2026), the EMODnet Physics database listed 582 unique institutions across 25 platform categories. Engagement with data collectors and managers yielded 134 responses, of which 88 were retained as usable methodological responses after quality screening. Among the 88 usable methodological responses, only 16 (18.2%) included a resolvable OBPS DOI or URL, although nearly all could be mapped to at least one recognizable program, method, or methodological framework. This pattern suggests that the community has embraced programmatic alignment and methodological documentation in many cases but has not yet normalized persistent method citation. From the EMODnet inventory and institutional responses, key methods used across several platform communities were identified, highlighting the need for more systematic documentation and deposition in OBPS. We recommend integrating persistent method identifiers into data-submission workflows, developing machine-readable method documentation standards, and treating methodological documentation as a routine research output within observing communities.