NEW: The WMO Unified Data Policy (Res.1) brochure, with the full text of Resolution 1, can be found here. 
Catalogue of core data can be found here.
WMO Unified Data Policy Approved by Congress
The 2021 Extraordinary World Meteorological Congress (11-22 October) approved the WMO Unified Data Policy, along with two other sweeping initiatives – the Global Basic Observing Network (GBON) and the Systematic Observations Financing Facility (SOFF) – to dramatically strengthen the world’s weather and climate services through a systematic increase in much-needed observational data and data products from across the globe.
The Unified Data Policy, GBON and SOFF have been painstakingly developed through extensive consultation with thousands of experts and other stakeholders around the globe to meet the explosive growth in demand for weather and climate data products and services from all sectors of society.
Approval of the Unified Data Policy provides a comprehensive update of the policies guiding the international exchange of weather, climate and related Earth system data between the 193 Member states and territories of WMO. The new policy reaffirms the commitment to the free and unrestricted exchange of data, which has been the bedrock of WMO since it was established more than 70 years ago.
Why has WMO updated its data policy?

The last decades have seen explosive growth in the demand for weather, climate and water monitoring and prediction data to support essential services needed by all sectors of society, as they face issues such as climate change, increasing frequency and impact of extreme weather, and implications for food security.
The free and unrestricted exchange of observational data from all parts of the world and of other data products among all WMO Members must be updated and strengthened to accommodate this growing demand. As the responsibilities of the National Meteorological and Hydrological Services (NMHSs) continue to expand, a growing list of application areas beyond the traditional weather, climate and water activities need to be supported by WMO observing, data exchange and modelling systems. WMO data policy must therefore evolve to accommodate areas such as atmospheric composition, oceans, cryosphere and space weather.
What are the benefits of updating WMO data policy?

The new WMO Unified Data Policy will help the WMO community strengthen and better sustain monitoring and prediction of all Earth-system components, with massive socioeconomic benefits as a result. It will lead to additional exchange of all types of environmental data, which in turn will enable all WMO Members to deliver better, more accurate and timely weather- and climate-related services to their constituencies.
Highlights of the WMO Unified Policy for International Exchange of Earth System Data
Data exchange for the 21st century
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Integrated Earth system data policy – encompassing all WMO-relevant Earth system data: weather, climate, hydrology, ocean, atmospheric composition, cryosphere, space weather. It builds on existing WMO data policies used successfully in the past: Resolutions 40 (Cg-XII) (weather), 25 (Cg-XIII) (hydrology) and 60 (Cg-17) (climate). |
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Clear commitment to free and unrestricted data exchange – clarifying the explicit and literal interpretation of the term “free and unrestricted” exchange, and expressing clear organizational commitment to it as the core principle of the policy. |
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Expanded scope and purpose – introducing new terminology on data, replacing “Essential” and “Additional” data (Resolution 40), with “Core” data (standard practice, shall be exchanged) and “Recommended” data (best practice, should be exchanged). The scope and purposes of Core and Recommended data, respectively, are described in general terms for each domain or discipline. |
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Call for subsequent implementation of policy via regulatory material – specific details of what data are to be considered Core and Recommended will be included, and regularly updated, in the WMO Technical Regulations. |
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Includes guidelines for national implementation and public-private engagement.
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