text: The Integrated Carbon Observation System (ICOS) is a research infrastructure to quantify the greenhouse gas balance of Europe and adjacent regions. In November 2015 it received the international legal status of ERIC (European Research Infrastructure Consortium) by decision of the European Commission. It is recognized by The European Strategy Forum on Research Infrastructures (ESFRI) as a landmark European research infrastructure. It consists of a harmonized network of almost 150 long-term observation sites for the domains of atmosphere, ecosystems and ocean. The network is coordinated through its Head Office, the central data portal and central facilities including an atmosphere, ecosystem and ocean thematic center, and central analytical laboratories.
  ICOS provides the essential long-term observations required to understand the present state and predict future behavior of the global carbon cycle and greenhouse gas emissions. It monitors and assesses the effectiveness of carbon sequestration and/or greenhouse gases emission reduction activities on global atmospheric composition levels, including attribution of sources and sinks by region and sector.
  The highly standardized network offers improved access to data and enables the development of flux products for research and political application. ICOS is a state-of-the-art facility for the European research community. It contributes to the European share of global greenhouse gas observations under Group on Earth Observations (GEO), World Meteorological Organization GAW and GCOS programs.