EMODnet river node: a near real time hydrological service designed for the coastal community

Rivers significantly influence coastal ecosystems by delivering freshwater, nutrients, and sediments that support biodiversity and help counteract beach erosion. However, they also act as conduits for pollution, transporting harmful chemicals and waste, including marine litter and microplastics, from inland areas to the ocean.Rivers also create complex hydrodynamic interactions with coastal circulation, affecting water movement, stratification, mixing patterns, and the formation of fronts. These dynamics intensify during extreme events like heavy rainfall, floods, and storms, which can increase the volume and speed of river flow, leading to greater impacts on coastal areas. Climate change compounds these effects by increasing the frequency and intensity of extreme weather events.For these reasons, it is crucial that state-of-the-art operational coastal numerical models incorporate near-real-time river data to improve the quality of hydrodynamic forecasts. These forecasts are essential for supporting decision-making in environmental protection and search-and-rescue operations during extreme events.To meet these needs, the EMODnet River Node has been designed to provide a dedicated hydrological service for the coastal community. It offers free access to near-real-time river data in a standardized format, adhering to the FAIR principles, all on a single platform. The system collects data from the hydrologic station nearest to each river's coastal area, excluding stations influenced by tides. The service currently provides river flow data for all stations and, where available, water temperature and water level data. It integrates information from over 1,000 stations, supplied by 40 national and regional water administrations across 22 countries on three continents: Europe, North America, and South America. In the near future, the service aims to continue expanding its coverage and include additional river data, such as biogeochemical information.