The Global Runoff Data Centre: A building block in the chain of reproducible hydrology

The Global Runoff Data Centre (GRDC) operates under the auspices of the World Meteorological Organization (WMO) at the German Federal Institute of Hydrology (BfG). It serves an important function for the scientific community as an archive for global runoff data. In 2022, the GRDC was referenced as a data source in over 100 peer-reviewed publications. 
Awareness of the need for reproducibility in hydrologic science has grown considerably in recent years. Thus, data archives also have the responsibility to improve their infrastructure to meet these requirements. Essential measures include making data and programs available in public repositories, containerization of computational environments and the provision of application programming interfaces (APIs).
To achieve these goals, the GRDC uses web portals for data provision, develops APIs for script-based data access, and provides program libraries in R or Python, e.g. for data analysis, as open source on repositories such as Github. We show the implementation status of these measures as well as positive effects that have resulted from the implementation, but also highlight obstacles and challenges in achieving a fully open and unrestricted data world.