The Global Terrestrial Network for River Discharge (GTN-R) is a component of the Global Terrestrial Network - Hydrology (GTN-H) supported by Global Climate Observing system (GCOS) and the Hydrology and Water Resources Programme of the WMO (HWRP). The basic idea of the GTN-R project is to draw together the already available real-time discharge data provided by the National Hydrological Services (NHS) and to redistribute it in a standardised way. Core component is the GCOS Baseline River Network of gauging stations located near to the mouth of the World's major rivers. In cooperation with the Hydrological Services of the WMO Member States this network is constantly being extended by confirmation of additional stations. The GCOS Baseline River Network is a project in progress with a current status as of December 2014 of 245 gauging stations worldwide.

GRDC contributes to the GTN-H by the collection of river discharge data of these so-called GTN-R stations. As a first step, the data of daily river discharge at the GRDC stations corresponding to the GCOS Baseline River Network are provided to the public via the Geoportal of the German Federal Institute for Hydrology (BfG) using a standard Sensor Observation Service (SOS). The provision via the GEOSS Portal is intended (further details will be communicated in due time):