In a landmark move, ECMWF is poised to announce a new phase in its data sharing strategy

As part of its strategy and ongoing commitment to open science, ECMWF (The European Centre for Medium-Range Weather Forecasts) has been opening its extensive data catalogue and making its science more widely open and accessible.

The organisation holds one of the world’s largest meteorological archives, exceeding 1.3 exabytes of data. Starting with historical data and charts, and ECMWF is now moving to make real-time forecast data openly available. By making its data openly available, ECMWF is supporting the UN’s Early Warnings for All initiative and enabling societies worldwide to better anticipate extreme weather, protect lives and livelihoods, and build resilience in the face of a changing climate.

Florence Rabier, ECMWF Director-General, comments: “Since 2019, together with the support of our 23 Member States and 12 Co-operating States, the team has worked very hard to transition our data to be more open, with more and more datasets becoming FAIR (Findable, Accessible, Interoperable and Reuseable), and this, in an equitable way. Access to ECMWF’s information has been transformed.”

As part of the move, there are no longer charges for information/data costs, but only delivery costs to specialised users, where relevant.

With approximately 100 TB of data produced a day comprising over 450 parameters, you can appreciate that while our data is freely accessible, delivery is not without cost. The nature of meteorological data – large, complex, and continuously updated – poses substantial challenges for managing the volumes, ensuring reliable and timely delivery, and maintaining our operational requirements to our Member and Co-operating States.

Florence adds: “Today, we are unveiling our plan to achieve our full open data status by the end of 2025, earlier than anticipated, by providing the complete ECMWF Real-time Catalogue under a Creative Commons licence. From 1 October, ECMWF will make its forecast data free and open at a 25 km resolution in real time with what we call no latency - no delay. Next, we will take an even bigger step by increasing the resolution of this offering to the native 9 km, but with a latency of 2 hours - given the higher resolution of these datasets, or earlier with the appropriate associated delivery charges for specialised users.”

ECMWF has already made significant strides on the pathway to fully open data:

• Open Charts: ECMWF offers timely delivery of its data in the format of pre-made charts. Over 400 charts are available under the CC-BY-4.0 licence, and users can log in to create custom collections for their forecasting needs.
• Responding to public good/societal benefit requirements: ECMWF also offers a delivery charge fee-waiver scheme to support public good activities such as early warning initiatives, research projects, and humanitarian aid. National Meteorological and Hydrological Services (NMHS) that are members of the World Meteorological Organization (WMO). In particular, those who are supported by the UN-based Systematic Observations Financing Facility (SOFF) can currently access a maximum-resolution dataset that is custom designed to support their official duty activities for the protection of life and property. SOFF is a United Nations-backed global funding mechanism aimed at supporting countries in generating and exchanging basic weather and climate data through systematic observations, especially in areas with limited resources
• Enhanced data accessibility: Expansion of data services to provide more user-friendly access. Open data is available directly from ECMWF or via public cloud providers, and there are several open tools to support data use and interpretation. Furthermore, ECMWF provides example Jupyter Notebooks to assist users in understanding beginner, intermediate and advanced processing of forecast products.
• Adapting to user needs: Recognising users' diverse needs, ECMWF makes data available in various popular formats, including charts, and directly via web interfaces and API options for data download. This adaptability facilitates easier integration and use of our datasets across different platforms and projects.

As part of the move to open data, ECMWF is highlighting the importance of attribution

Emma Pidduck, Data Policy and Partnerships Coordinator, explains that just as researchers cite their sources in their papers, attribution in the use of open data is the same concept. She says: “Users of ECMWF’s open data sources understand that attribution is really important. It not only adds credibility and value to their work as ECMWF is a trusted source of information, but also supports continued public investment in open, high-quality forecasting that our Member and Co-operating States make in the organisation. Additionally, it helps ECMWF discover and share the innovative ways the user community is using our data and demonstrates the value of the Centre’s work to decision makers.”

A unique relationship with the 35 nations behind ECMWF

Over the past 50 years, substantial support has been invested in ECMWF from its Member States, who are at the heart of every decision, ensuring ECMWF delivers a wide range of benefits.

Florence Rabier concludes: “Together with Member and Co-operating States, we innovate and co-develop products, share best practice through training and invest in new initiatives and technologies to produce and distribute even higher rates of data. The European Weather Cloud (EWC) is a great example of new technical capabilities that we foster. This provides, for example, computing resources and unique software tools to facilitate deployment of machine learning models and this also allows them to expand services to their own citizens. Through their investment in ECWMF, Member States also access High Performance Computing capabilities, in proportion of 25% to 50% of these resources, including a newly acquired set of GPUs essential to train AI/ML models.”

ECMWF has chosen the Creative Commons CC-BY-4.0 licence for all of its open data. Under the CC-BY-4.0 licence, attribution is a legal requirement.
 An example attribution could be:

“Adapted from “ECMWF IFS 15-day Forecast Data” by ECMWF, licensed under CC BY 4.0, available at https://data.ecmwf.int/forecasts/”

ENDS – 

For further information, please contact: pressoffice@ecmwf.int or Lorna Campbell 0044 (0)7836 625999. 

About ECMWF 

The European Centre for Medium-Range Weather Forecasts (ECMWF) is a world leader in numerical weather predictions, providing high-quality data for weather forecasts and environmental monitoring. As an intergovernmental organisation, we collaborate internationally to serve our members and the wider community with global weather predictions, data and training activities that are critical to contribute to safe and thriving societies.   

The success of our activities depends on the funding and partnerships of our 35 Member and Co-operating States who provide the support and direction of our work. Our talented staff, together with the international scientific community and our powerful supercomputing capabilities, are at the core of a 24/7 research and operational centre with a focus on medium- and long-range predictions. We also hold one of the largest meteorological data archives in the world, including ERA5 funded by the European Union Copernicus programme.  

Our mission: Deliver global numerical weather predictions focusing on the medium-range and monitoring of the Earth system to and with our Member States.  

Further information:  

Available Open Datasets 

• ECMWF Open IFS Data
• ECMWF Open AIFS Data
• S2S Data (sub-seasonal range)
• TIGGE Data (research ensemble)
• ERA5
• ECMWF Seasonal Forecast via the Climate Data Store

 

𝗔𝘁𝘁𝗿𝗶𝗯𝘂𝘁𝗶𝗼𝗻 𝗿𝗲𝗾𝘂𝗶𝗿𝗲𝗺𝗲𝗻𝘁𝘀 𝗳𝗼𝗿 𝗢𝗽𝗲𝗻 𝗗𝗮𝘁𝗮 - 𝘄𝗵𝘆 𝗱𝗼𝗲𝘀 𝗶𝘁 𝗺𝗮𝘁𝘁𝗲𝗿?
In the same way that researchers will cite their sources in their paper, attribution is the same concept for data. ECMWF has chosen the Creative Commons CC-BY-4.0 licence for all of its open data. Under the CC-BY-4.0 licence, attribution is a legal requirement and is comprised of the following important aspects:

An example attribution could be:

“Adapted from “ECMWF IFS 15-day Forecast Data” by ECMWF, licensed under CC BY 4.0, available at https://data.ecmwf.int/forecasts/”

Here’s why attribution is important:
📍It supports continued public investment in open, high-quality forecasting
It demonstrates the value of ECMWF’s work to decision-makers
📍It helps us discover and share the innovative ways you use our data

Open data licence: description View licence

A subset of ECMWF real-time forecast data from the IFS and AIFS models is made available to the public free of charge. Their use is governed by the Creative Commons CC-4.0-BY licence and the ECMWF Terms of Use. This means that the data may be redistributed and used commercially, subject to appropriate attribution.

For some users, these open data can also be delivered via the ECPDS platform to a nominated FTP server; in this case, they may be subject to service charges.

Additional data, including at higher resolutions and more parameters, can be obtained from the ECMWF Product Requirements Catalogue or by contacting a Catalogue contact point for more information. Charges and licence conditions apply.

This page describes the subset of free and open IFS parameters available. For AIFS products, all parameters are freely and openly available; more information can be found in the dataset descriptions for the Deterministic AIFS and Ensemble AIFS.

How to access real-time open data

For more information on accessing these products, please see the user documentation or visit the ECMWF Support Portal.

Sign up for an open data community mailing list, a joint project with EUMETSAT, Met Norway and the German national meteorological service DWD to share new and updated open datasets, relevant resources, conferences and articles.

Product description

These products are a subset of the full Catalogue of ECMWF Real-time Products and are based on the medium-range (high-resolution and ensemble) and seasonal forecast models.

IFS data are released 1 hour after the real-time dissemination schedule. AIFS data are released as soon the data are produced. For further details about the available AIFS products, see the dataset descriptions for the Deterministic AIFS and Ensemble AIFS.

Products are produced at 0.25 degree resolution in GRIB2 format unless stated otherwise. Since July 2023, the encoding of products in GRIB2 has changed to use CCSDS compression.

Important: higher-resolution versions of the same products are available via the Product Requirements Catalogue and service charges may apply.

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