GRDC-Caravan: extending the original dataset with data from the Global Runoff Data Centre

Abstract

Large-sample datasets are essential in hydrological science to support modelling studies and global assessments. The Global Runoff Data Centre (GRDC) is an international data centre operating under the auspices of the World Meteorological Organization (WMO) at the German Federal Institute of Hydrology (BfG). Established in 1988, it holds the most substantive collection of quality assured river discharge data worldwide. Primary providers of river discharge data and associated metadata are the National Meteorological and Hydrological  Services of WMO Member States. As the awareness for open data and reproducibility has increased in recent years, GRDC is working to simplify data provision to its users and to comply with the FAIR (findable, accessible, interoperable, reusable) principles. GRDC data and products are accessible online for non-commercial use (https://grdc.bafg.de). However, there are still hurdles on the way to a completely open and free exchange of data such as restrictive data policies and a lack of data standardisation. Caravan is a community initiative to create a large-sample hydrology dataset of meteorological forcing data, catchment attributes, and discharge data for catchments around the world (Kratzert et al. 2023). Compared to existing large-sample hydrology datasets, the focus on Caravan is to use globally consistent forcing and attribute data to facilitate global studies. Additionally, Caravan provides the code to derive community extension on Earth Engine with as little as catchment boundaries and streamflow data required. The vision of Caravan is to provide the foundation for a truly global open source community resource that will grow over time.       This dataset is the 6th extension to the original Caravan data set. It is based on a subset of hydrological discharge data and station-based watersheds from GRDC, which are covered by an open data policy (Attribution 4.0 International; CC BY 4.0). The dataset covers stations from 5357 catchments and 25 countries, spans 1950 – 2023, and is already publicly available on Zenodo: https://zenodo.org/records/10074416   Reference: Kratzert, F., Nearing, G., Addor, N. et al. Caravan - A global community dataset for large-sample hydrology. Sci Data 10, 61 (2023). https://doi.org/10.1038/s41597-023-01975-w