Strengthening global hydrological data sharing and capacity for climate science and water services

Global water systems are under increasing pressure from climate change, hydrological extremes, and competing demands on limited freshwater resources. Robust, interoperable data and data sharing infrastructures are essential to advance scientific understanding, support operational forecasting, and inform effective water management and climate adaptation strategies. The Reference Observatory of Basins for INternational hydrological climate change detection (ROBIN) and the Global Hydrological Status and Outlook System (HydroSOS) represent complementary international efforts to unify and leverage hydrological data for science and service delivery. 

ROBIN, coordinated by the UK Centre for Ecology & Hydrology, addresses critical gaps in global streamflow observations by integrating long-term, near-natural catchment data to form a global Reference Hydrometric Network. This open-access dataset, comprising >3000 of quality-controlled streamflow records from near-natural catchments spanning diverse climates and geographies, is shared under common standards and protocols to enable global-scale climate change trend detection, model evaluation, and large-scale hydrological research. The initiative also fosters long-term collaboration among researchers and institutions, promoting shared infrastructure, code libraries, and harmonised metadata to support international scientific agendas. ROBIN is aligning its data-sharing processes with the GRDC, ensuring interoperability and complementarity between datasets, and strengthening the long-term international hydrological data legacy. Through collaboration with the FRIEND-Water and EUROFRIEND networks, ROBIN is increasing its emphasis on social hydrology, enabling analyses that better capture human–water interactions, vulnerability, and adaptation alongside climate-driven hydrological change. 

The World Meteorological Organization’s HydroSOS builds operational capacity for standardised hydrological status assessments and sub-seasonal to seasonal outlooks across spatial scales. HydroSOS enhances national and regional water information systems by linking local observations, forecasts, and global services to produce consistent products for water resources management, disaster risk reduction, and climate resilience. Developed and supported by the UKCEH, the HydroSOS portal provides open access to these standardised “change from normal” assessments, enabling transparent comparison of hydrological conditions across countries and regions. It emphasises the value of consistent and standardised hydrological information among National Meteorological and Hydrological Services, contributing to united global water information frameworks and decision support tools. 

Together, ROBIN and HydroSOS exemplify synergistic efforts to overcome current and historical fragmentation in hydrological data and services. By promoting open data practices, harmonised standards, and shared technical capacity, these initiatives enable a more integrated global hydrological data ecosystem that supports science, policy, and operational services in the face of evolving environmental challenges and a need to improve resilience to extreme hydrological events both now and in the future.