Time-series data are essential in environmental sciences, both for research and for timely monitoring and warnings amid increasing climatic extremes. The seven Helmholtz Centers in the Earth and Environment (E&E) Research Field operate some of the world’s largest environmental measurement infrastructures. Despite past efforts, a unified, community-driven framework for time-series and sensor metadata is still lacking. The STAMPLATE project addresses this gap by developing technical and semantic foundations to establish the SensorThings API as a flexible, interoperable standard for publishing time-series data with standardized metadata. All seven Centers are involved, supported by Fraunhofer IOSB and the Open Geospatial Consortium.