INAR RI coordinates the Finnish national contributions to ICOS (Integrated Carbon Observation System), ACTRIS (Aerosol, Clouds and Trace Gases Research Infrastructure), eLTER (Integrated European Long-Term Ecosystem, Critical Zone & Socio-Ecological Research Infrastructure) and AnaEE (Infrastructure for Analysis and Experimentation on Ecosystems).INAR RI integrates the nationally operated facilities into a benchmarking RI in atmosphere–ecosystem domain.INAR RI has currently 30 sites (17 co-located), several laboratories and mobile units and two data infrastructures.This project has three main aims supporting the development of the RI: 1) development of long-term high-quality environmental observations for better quantification of land carbon sink and related climate impacts, 2) further integration of the environmental measurements and 3) development of services related to data and access to better respond to user’s needs.The project activities and data produced via INAR RI are relevant to the green transition and support the achievement of national carbon neutrality target.Improved assessment of carbon sink and related climate impacts (1st aim) will enable more accurate carbon footprint calculations, improved verification systems for carbon sequestration and enhancement of strategies and standards in carbon pricing.With the support of the project, novel co-location stations and mobile platforms will be implemented to further integrate INAR RI measurements (2nd aim).The project supports the development of INAR RI data services e.g. the user interface, and implementation of new data services such as GHG flux maps and climate impact verification tool (aligning with the goals of digitalisation), and strengthens physical and remote access to INAR RI (3rd aim).Upgrading and construction of research sites and platforms, further integration of various environmental research infrastructures and development of new services that this project enables bring significant added value to the operations of the RI e.g. via enhancing the attractiveness of the RI to the users.Unique additional value is the science case in atmosphere–ecosystem domain where four ESFRI infrastructures are working together with joint aim on improving the quantification of carbon sinks and the effects of important feedbacks e.g. from aerosols and albedo, shared methodologies, data flows and expertise in addressing a societally relevant question on e.g. land management impacts on climate. ReferenceFI-C[P3C3]-I[I6]Project locations Finland Project websitehttps://www.helsinki.fi/en/...