This year, ICOS celebrates its 10-year anniversary as an ERIC. In the decade that has passed, the ICOS network of greenhouse gas measurement stations has expanded from eight countries to sixteen. In 2015, the ICOS network consisted of 90 stations in Belgium, Germany, Finland, Italy, Netherlands, Norway, Sweden and Switzerland, while in 2025, the network had close to 180 stations in 16 member countries.
The geographical expansion of the ICOS measurement network is important for scientific reasons. To gain a representative picture of the greenhouse gas balance in Europe, including emissions, sinks and transport, ICOS seeks to have a sufficient coverage of stations across Europe and adjacent regions.
ICOS member countries actively develop their national networks of measurement stations. At the same time, there is work being done to invite new member countries to ICOS. Joining ICOS is possible for any EU country. Associated and third countries are eligible to join ICOS as member or observer countries, provided they meet certain legal requirements.
Having several countries in ICOS helps to make the scientific community more diverse, improves cooperation between scientific organisations in Europe and progresses the standardisation of greenhouse gas measurements. For the member country, being part of ICOS offers access to a Europe-wide scientific community, training and events, and strong links to European and global networks. It also promotes data standardisation and supports members in securing funding for multidisciplinary projects.
Here's a short look back into how ICOS grew from a network of eight member countries in 2015 to 16 member countries in 2025. The text excerpts below are from the news archive, and the link to the original news item can be found below each text excerpt.
The 2010’s - United Kingdom, Czech Republic and Denmark join ICOS
The United Kingdom (2016)
“At the beginning of July, United Kingdom has joined ICOS ERIC as the twelfth member of the ICOS RI pan-European network for greenhouse gas observations. The UK has a strong GHG science community across marine, atmospheric and ecosystem sectors and ICOS ERIC is looking forward to the ICOS UK future contributions to the network, including co-hosting of the ICOS Ocean Thematic Centre with Norway.
- Read the full story: ICOS ERIC welcomes UK as a new member (26 August 2016) https://www.icos-cp.eu/event/441
- Watch a video of Richard Sanders, now the Director of the ICOS Ocean Thematic Centre, explaining the UK's role in ICOS ERIC and global greenhouse gas observations (from 2016).
Czech Republic and Denmark (2016)
"At the 2nd ICOS ERIC General Assembly meeting, that took place in Lund, Sweden on Friday 15th April 2016, members of the GA unanimously adopted applications from two new countries – Czech Republic and Denmark."
- Read the full story: ICOS RI have two new member countries (27 October 2016): https://www.icos-cp.eu/event/448
The 2020’s – ICOS expands to Spain, Greece, Ireland and Hungary
Spain (2021)
"The Kingdom of Spain joins the Integrated Carbon Observation System, ICOS (--) The new stations will extend the standardised ICOS measurement network to the Spanish mainland, to the Canary Islands and to the Mediterranean Sea: areas that are strategically important and increase the geographical spread of the network.
“We are very pleased to welcome Spain to ICOS. With the extended network of stations, ICOS data will cover areas from Canary Islands to Scandinavia and even Svalbard in the north. This allows us to see how carbon emissions move along with the winds, and how sinks are distributed at land and in the oceans. Based on our high-quality data, scientists can better inform societies on the effects of climate change”, says Dr Werner Kutsch, Director General of ICOS."
- Read the full story: PRESS RELEASE: Spain invests in climate change research and joins ICOS (19 November 2020) https://www.icos-cp.eu/event/1010
Hungary (2022)
“Hungary is committed to climate protection. It is a small but relevant step in our efforts that Hungarian measurement stations will be integrated into this important European network. ICOS verification for Hungarian measurements provides us with a widely accepted standard. Moreover, Hungary can be supported by the science and the knowledge generated by ICOS on greenhouse gases when making decisions aiming to decrease carbon emissions,” said György Urkuti, the Ambassador of Hungary to Finland.
- Read the full story: Hungary invests in climate research, joining ICOS, the European greenhouse gas observation network (21 June 2021) https://www.icos-cp.eu/event/1069
Greece and Ireland (2023)
"ICOS has welcomed Greece and Ireland to the network starting January 1, 2023. The two new member countries brought 14 new stations to the network, which now has more than 170 stations measuring greenhouse gases in Europe and the adjacent oceans. (--) The accession of Greece provides scientists with the possibility to compare data from an area reaching all the way from the Atlantic Ocean to the Eastern Mediterranean Sea, and from the Canary Islands to Finnish Lapland. This allows ICOS to quantify carbon emissions as they move along with the winds, and to see how sinks are distributed on land and in the oceans. (--)
“It is essential that climate observations carried out in Ireland are of high quality and are comparable with data from observations being carried out across Europe and globally. Membership of ICOS will enable this, as well as promoting the sharing of scientific understanding and expertise which is vital to develop our knowledge and deepen our understanding of greenhouse gas emissions and removals”, said Eamon Ryan, the Minister for the Environment and Climate of Ireland."
- Read the full story: Greece and Ireland have joined ICOS (13 March 2023) https://www.icos-cp.eu/event/1281
Switzerland joins as Member country (2023)
“After 10 years as an Observer, Switzerland has now become a full Member of ICOS. The membership required a particular decision by the Swiss parliament to allow membership in an EU organisation such as ICOS. Only five other ERICs were given the same status. The Swiss application was accepted at the ICOS General Assembly in May 2023. With full membership, ICOS Switzerland will get voting rights in the General Assembly, the highest decision-making body of ICOS. (--)
”Given the current, rather complex situation of Switzerland within the European research arena, becoming a member of ICOS is a great success for the whole ICOS Switzerland consortium. We see this as an appreciation for the large efforts we have done in the past, as part of the ICOS community, from its preparatory phase in 2008, the labeling of Jungfraujoch and Davos in 2018 and 2019, to our continuing commitment to maintain the high standards of our ICOS stations in Switzerland,”, says Nina Buchmann, Focal Point of ICOS Switzerland."
- Read the full story: Switzerland strengthens climate research by becoming a Member of ICOS https://www.icos-cp.eu/event/1315
- Watch the video from the Davos ICOS station below. Film by Artan Hajrullahu and Sophie Graf (ETH Zurich), with footage taken in summer by Matthias Paintner.