Credit: Aerophile - Hervé Thouroude
In a world of increasing weather and climate extremes, it is more important than ever for organisations to work together globally, to help make societies safer, better prepared, and more resilient.
On World Meteorological Day (23 March), run by the World Meteorological Organization (WMO), ECMWF is joining forces with Météo-France and the Ballon Generali de Paris to highlight the essential role of weather prediction in protecting lives and strengthening climate resilience.
With the theme of this year’s World Meteorological Day being ‘Observing today, protecting tomorrow’, the organisations are uniting to demonstrate how international scientific excellence and national operational expertise benefit society.
The collaboration builds on an invitation extended to the EU's Copernicus Climate Change Service (C3S) and the Copernicus Atmosphere Monitoring Service (CAMS), both implemented by ECMWF, to join the Ballon Generali de Paris as scientific collaborators last spring.
Ballon Generali de Paris (L-R): Matthieu Gobbi (CEO of Aerophile), Jérôme Giacomoni (President of Aerophile), Simon Blaquiere (Director of the Generali Climate Lab), Virginie Schwarz (President and CEO of Météo-France), Matthieu Chevalier (Head of Forecasts Evaluation at ECMWF). Credit: Aerophile - Hervé Thouroude
Global observations
ECMWF receives 800 million observations daily, with 60 million quality-controlled observations available for use in its models and products every day. These observations – drawn from satellite measurements to sea-surface temperature monitoring – are used to create initial conditions for modelling and to simulate how those conditions may play out in a range of scenarios.
Using both traditional physics-based modelling and artificial intelligence (AI)-driven models co-developed with Météo-France and other Member and Co-operating State partners, these data, which include temperature, wind and rainfall measurements, produce forecasts on a range of timescales from the medium range (four days to two weeks) through sub-seasonal (up to six weeks) to seasonal (six weeks to a year).
Observational data and modelling systems are essential not only for weather forecasting but for understanding and analysing climate change from both a global and regional perspective.
Meteorological and hydrological services and associated consortia across ECMWF’s Member and Co-operating States, including Météo-France, combine ECMWF’s data with their own observations and models to produce local forecasts that inform decision-making across civil protection, aeronautics, agriculture, energy, transport and insurance, as well as for the general public.
At the Ballon Generali de Paris, visitors can now explore three climate indicators produced by ECMWF through the framework of C3S, helping connect scientific information with public understanding.
Météo-France has also released new data showing that in 2025, the average temperature recorded in France was 2.5 °C above the average value of the pre-industrial era, due to the combined effects of global warming and natural year-to-year variability.
Virginie Schwarz, President and CEO of Météo-France explaining how partnerships and AI frameworks like Anemoi are transforming forecasts, improving climate resilience, and helping societies prepare for more extreme weather.
A shared scientific engine: IFS and ARPEGE
At the heart of the collaboration between ECMWF and Météo-France is the Integrated Forecasting System (IFS/ARPEGE), a global numerical weather prediction system jointly developed and maintained by both institutions for the benefit of ECMWF’s 35 Member and Co-operating States.
The system combines advanced atmospheric dynamics, physical modelling, and cutting-edge data assimilation techniques to produce some of the world’s most accurate global forecasts.
The IFS is ECMWF’s operational global system, underpinning physics-based forecasting and analysis across medium-range, sub-seasonal and seasonal timescales, as well as global atmospheric composition forecasts for CAMS and the ERA5 global climate reanalysis for C3S.
At Météo-France, the same codebase runs as ARPEGE – optimised with a variable-resolution grid to enhance national performance, run rapidly after observations are collected, and deliver tailored services.
In practice, both centres rely on the same core meteorological engine, with configurations adapted to their respective missions: global medium-range forecasting at ECMWF and four-day operational forecasting at Météo-France.
In addition, Météo-France’s regional model, AROME, is based on the same codebase in a specific configuration, co-developed with 26 partners in the ACCORD consortium.
Matthieu Chevallier, Head of Forecasts Evaluation at ECMWF explaining why collaboration matters – from IFS-ARPEGE and Anemoi to delivering trusted forecasts that protect people and critical sectors.
Forecasts that save lives
World Meteorological Day provides an opportunity to celebrate this long-standing partnership and recognise the generations of scientists whose work underpins today's forecasting capability.
“The societal value of global forecasting is immense and profound in protecting life and property,” said Matthieu Chevallier, Head of Forecasts Evaluation at ECMWF.
“ARPEGE and the IFS along with other regional models across Europe that have stemmed from it, are powerful examples of European scientific cooperation at its best and help ensure that cutting-edge science translates into timely, trusted warnings for our citizens. Our move earlier this month to make the portable version of our forecasting system fully open source, only serves to broaden the opportunity to use these shared assets for maximum benefit for all interested sectors from academia to industry.”
Virginie Schwarz, President and CEO of Météo-France, said: “International cooperation is essential in meteorology, both for operational forecasting and for research and development. Météo-France works closely with the European Centre for Medium-Range Weather Forecasts (ECMWF), which coordinates European efforts in medium-range numerical weather prediction and supports national meteorological services.”
Both Météo-France and ECMWF are working with the support of a landmark partner, the Ballon Generali de Paris.
Through this platform, Generali supports the visibility and accessibility of high‑quality weather and climate data, helping to bridge scientific observation and public understanding. By illustrating how international scientific cooperation can be shared with society, the Ballon Generali de Paris highlights the role of observation and forecasting in improving the understanding of climate risks.
Simon Blaquière, Head of Generali Climate Lab, concludes: “By relying on the scientific excellence of organisations such as ECMWF and Météo‑France, weather and climate data can be transformed into actionable information, enabling more refined risk assessment at the most local scale and placing prevention at the forefront. This enhanced capacity to anticipate is essential to strengthening long‑term preparedness in the face of intensifying climate risks.”
Further reading
Artificial intelligence (AI) is transforming weather and climate science – from how models are built to how information is delivered and used. At ECMWF, this shift is being driven collaboratively with our Member and Co-operating States, building on decades of shared expertise in data, infrastructure and forecasting.
Learn more about how ECMWF’s data, infrastructure and AI-ready systems are supporting the next generation of weather and climate forecasting, in our In Focus feature series. Our latest edition, Powering the AI weather revolution: from ERA5 to AI-ready pipelines highlights key developments including Anemoi.
Anemoi
Anemoi is a shared, open-source framework co-developed by ECMWF and Member States to support machine learning research and operational innovation. This collaborative initiative enables rapid innovation while maintaining the scientific rigour and transparency required for public safety.
Discover more about Anemoi in the animation below.