The European Centre for Medium-Range Weather Forecasts (ECMWF) celebrates its 50th anniversary in 2025. To mark the occasion, it has issued several publications and organised events, including a review of the first ten years of its involvement in the programme. CopernicusCopernicus is the European Union's flagship in the field of Earth observation, which monitors our planet and its environment for the benefit of all European citizens. The publication, entitled "Ten years of Copernicus at ECMWF", highlights ECMWF's leading role in implementing two key services of the programme: Copernicus Atmosphere Monitoring Service (CAMS) a Copernicus Climate Change Service (C3S)The overview maps the commitment of these services to providing high-quality data under the Copernicus programme and shows how their implementation has led to significant milestones in climate and atmospheric science, while supporting transparency, knowledge exchange and global collaboration.

During the first ten years (2014-2024), CAMS and C3S services leveraged ECMWF's extensive operational infrastructure, global network and numerical modelling expertise. They integrated large volumes of satellite and in situ monitoring networks, including ground-based weather stations, ocean buoys and air quality instruments. The result is state-of-the-art monitoring and forecasting systems for climate and atmospheric composition, providing deep insights into air quality, climate reanalysis, seasonal forecasts, greenhouse gas (GHG) and air pollutant concentrations, solar radiation and other aspects at a global level. This information is made freely available to the public and private sectors, as well as to millions of users worldwide, supporting efforts to better understand environmental issues and helping to inform decisions, policies and emergency responses based on current, real-world data.

CAMS – Advances in Atmospheric Monitoring

Over a decade of operational implementation under ECMWF, CAMS has established itself as a leader in air quality and atmospheric composition monitoring. It develops global and regional modelling systems that include in situ and satellite observations to provide near-real-time forecasts, pollutant and greenhouse gas analyses, emission inventories, solar radiation assessments and climate variables. For example, CAMS monitored the large Canadian fires in the summer of 2024, which were responsible for significant emissions of carbon and air pollutants. CAMS predicted the behaviour of the smoke plume that crossed the Atlantic Ocean and affected particle concentrations in Europe. CAMS data is increasingly used to help assess the effectiveness of air pollution mitigation measures and to support pollution reduction strategies through online policy services and tools such as the Air Quality Toolbox. The service is also a crucial source of information for the revised Air Quality Directive adopted by the European Council in 2024. CAMS data is playing an increasingly important role in air quality monitoring, underpinning smartphone apps and wearable technologies that alert users to elevated pollution levels.

C3S – Key Milestones and Achievements

C3S has achieved significant milestones in providing and analyzing climate data. One of the most significant achievements is ERA5 – fifth generation reanalysis dataset, which has become a cornerstone of the use of global climate data. ERA5 provides details of atmospheric conditions around the world from 1940 to the present. Its reliability has led to widespread acceptance in the scientific community, including extensive citations in reports of the Intergovernmental Panel on Climate Change (IPCC). ERA5 data is also used by the EU to inform and shape its climate policies and support strategies in line with the Paris Agreement. A recent study showed the socio-economic benefits of ERA5, for example in the optimal location of offshore wind farms, which resulted in annual savings in Europe of €30-33 million. These financial gains for the European offshore wind industry cover the production costs of ERA5 and almost the entire programme. ERA5 is also crucial for advances in machine learning and artificial intelligence in weather forecasting, becoming the leading dataset for training AI-driven models in numerical weather prediction.

Shared commitment to data access

Both CAMS and C3S have a common data architecture that ensures users can seamlessly extract, process and analyze Freely available climate data and atmospheric composition data. The Climate Data Store (CDS) provides users with open access to reliable data. Similarly, the CAMS Atmosphere Data Store (ADS) offers a single platform for accessing global and regional datasets on atmospheric composition. This joint effort to simplify data access and usability within the Copernicus programme enables researchers, businesses, decision-makers and millions of users to freely access valuable climate and atmospheric information.

A look into the future

Over the past decade, CAMS and C3S have evolved from research-focused initiatives to fully operational services, becoming trusted sources of atmospheric and climate data. The second phase of ECMWF implementation is underway in 2021-2028, during which the CO₂ Monitoring and Verification Support (CO2MVS) capacity is being developed within CAMS to monitor anthropogenic CO2 and methane emissions based on observations. C3S is developing its capabilities in parallel, including the development of new generation reanalyses ERA6, which will provide even greater accuracy, resolution and coverage. The services will also benefit from the space component of the Copernicus programme, including the launch of a new generation of satellites in 2025-2028. After 2028, deeper integration of artificial intelligence and machine learning is expected, which will further increase the accuracy and usability of the data and strengthen the socio-economic impact of CAMS and C3S in key sectors such as energy, finance, agriculture and disaster management.

As Jean-Noël Thépaut, co-founder and former director of Copernicus services at ECMWF, stated: "It has been an extraordinary development to witness how Copernicus at ECMWF has become a world leader in climate and environmental data."The services are entering a new decade of implementation with the aim of enriching our understanding of the climate and atmosphere in Europe and around the world. Spring