"Unlocking the potential of hydrological data in Copernicus: Improving access, interoperability and impact" workshop strengthens RA VI cooperation

A two-day workshop co-organised by the European Environment Agency and WMO concluded today with a clear message that unlocking the full value of hydrological data requires improved access, interoperability and stronger connections between national observations, Copernicus services, Earth observation, research and data standards.

The workshop brought together National Meteorological and Hydrological Services (NMHSs), Copernicus stakeholders, European and international organisations, researchers, data users and data specialists to explore how hydrological information can be more easily accessed, combined and used.

Participants highlighted the complementary value of in-situ and satellite observations. National hydrological services provide authoritative, long-term observations that underpin forecasting and water management, while Earth observation can extend monitoring to areas where in-situ observations are sparse and provide additional information during extreme events.

Presentations from partner agencies and initiatives, including ESA, EU-Hydro, INSIGHT and other Copernicus-related activities, demonstrated the growing range of hydrological data and products available across Europe. At the same time, discussions showed that making these resources work together requires more than data portals, APIs and common formats.

Shared semantics, FAIR vocabularies, metadata, quality information and agreed observing procedures are needed so that data from different sources can be understood consistently. Work on WaterML 2.0 and TimeSeriesML was highlighted as an important contribution to this effort.

Discussions also focused on the readiness of national hydrological data systems to meet evolving requirements for accessibility, quality, interoperability and integration with Copernicus and WMO infrastructures, highlighting both good practices and persistent practical barriers.

The workshop also examined the policy and infrastructure foundations for hydrological data sharing, including the WMO Unified Data Policy, WIS2, WHOS and core hydrological datasets. These frameworks provide important links between national, European and global levels and can help turn improved data availability into more systematic and interoperable data exchange.

The workshop also demonstrated the value of existing WMO regional coordination mechanisms and partnerships in connecting these efforts.

The Global Water and Data Resource (GWDR) Centre, hosted by the Federal Institute of Hydrology (BfG) in Koblenz, Germany, was represented by Stephan Dietrich, who recently took over the chairmanship of the WMO Regional Association VI Coordination Panel on Hydrology. Stephan Dietrich highlighted the potential of the Panel’s Knowledge Hub as a regional forum for sharing good practices and experiences, offering a practical way to connect initiatives and carry lessons from the workshop into the wider RA VI hydrological community.

Sylvain Grellet, a member of the RA VI Coordination Panel on Hydrology, contributed through his presentation on Water4All within the OneWater initiative, including work to improve the alignment of hydrological vocabularies and data across national providers. Mirza Sarac brought an additional regional perspective through activities of the International Sava River Basin Commission (ISRBC).

Together with other experts from RA VI teams and regional partners, their participation illustrated how existing WMO networks can connect operational hydrology, research, innovation and European data initiatives — helping to advance common priorities while building on existing structures and networks.

From discussion to follow-up

The final discussions focused on identifying common challenges, opportunities to improve data access and interoperability, and priorities for stronger collaboration, with the aim of developing shared recommendations and next steps.

The workshop comes at a timely moment for the RA VI hydrological community. Experts who participated in the EEA–WMO workshop are expected to contribute to the HydroSOS Workshop on 28 September and the RA VI-19 (II) with the RA VI Hydrological Assembly on 2 October, including the planned launch of the Regional Water Statement, will provide a further opportunity to bring the workshop’s themes into the broader regional agenda.

For WMO, the workshop reinforced the value of its role in bringing Members and partners together, supporting common approaches and standards, and providing mechanisms through which regional experience can be shared and translated into action.

The discussions concluded with recognition that many of the necessary building blocks already exist. The priority now is to connect them, strengthen implementation and share experience so that hydrological data can better support decisions on water, climate and disaster risk.