ICOS (Integrated Carbon Observation System) RI is a pan-European Research Infrastructure within the international carbon research community with expertize within atmosphere, ecosystem and ocean science. ICOS RI provides harmonizes and high precision scientific data on carbon cycle and greenhouse gas budget and perturbations.

The marine elements of the ICOS RI provides the long-term oceanic observations from the surface and interior ocean required to understand the present state and predict future behaviour of the global carbon cycle and climate-relevant gas emissions. The marine monitoring network consist of four categories of stations; surface ocean measurements from Voluntary Observing Ships, measurements within the water column at fixed positions, measurements within the water column along sections which are repeated regularly, and measurements from flux towers close to the sea. At present, more than 15 partners from 8 countries contribute to the marine data collection within ICOS, and the stations collect data from the south and north Atlantic, the Nordic Seas, the Mediterranean Sea, the Baltic Sea, and the Barents Sea. Even more partners will be involved in the future.

ICOS data is openly available at the Carbon Portal, and the marine part consist of data from both the surface and the entire water column.

OTC (Ocean Thematic Centre) coordinate and support the European network of Monitoring Stations Assembly (MSA), which consist of the marine station representatives. The OTC support is provided through labelling of stations, training, and data quality control.