CF (Climate and Forecast) metadata convention

CF (Climate and Forecast) metadata convention
Name	CF (Climate and Forecast) metadata convention
Abbreviation	CF
Domain	Earth sciences
First	2003
Latest	ongoing

CF (Climate and Forecast) metadata convention is a widely used specification for climate, atmospheric, oceanographic, and earth science data stored in self-describing formats. It defines metadata conventions that enable data interoperability, discoverability, and reuse across projects, institutions, and international programs. CF supports machine-readable descriptions of variables, coordinates, and ancillary information to facilitate analysis by diverse tools and communities.

Overview

The convention standardizes how to describe gridded and irregular dataset variables, coordinate systems, and ancillary data in file formats such as NetCDF, enabling integration with projects like World Climate Research Programme, Intergovernmental Panel on Climate Change, and agencies including National Aeronautics and Space Administration, National Oceanic and Atmospheric Administration, European Space Agency, Met Office, and CSIRO. It defines attributes for units, coordinates, and provenance that are compatible with software libraries and frameworks from organizations such as Unidata, Open Geospatial Consortium, European Centre for Medium-Range Weather Forecasts, and academic centers like Lamont–Doherty Earth Observatory and Scripps Institution of Oceanography.

History and development

Development began in the early 2000s with contributions from groups at Unidata, NOAA, UK Met Office, ECMWF, and universities including University of Oxford, Massachusetts Institute of Technology, University of California, Berkeley, and University of Reading. Key milestones paralleled initiatives such as the Global Climate Observing System, Global Ocean Observing System, and programs run by World Meteorological Organization and Group on Earth Observations. Influential workshops and meetings occurred at venues like American Geophysical Union conferences, European Geosciences Union assemblies, and forums organized by RDA (Research Data Alliance), shaping versions and errata distributed through community repositories and mailing lists maintained by Unidata and consortia of university and national laboratory partners.

Purpose and scope

The convention’s purpose is to ensure that datasets from models, reanalyses, satellites, and in situ campaigns produced by institutions such as NOAA National Centers for Environmental Information, NASA Goddard Space Flight Center, CSIRO Oceans and Atmosphere, National Center for Atmospheric Research, and observatories like Plymouth Marine Laboratory can be self-describing and interoperable. Scope covers coordinate metadata, cell methods, climatology, and standardized names used by communities active in projects by IPCC, WCRP, GCOS, and observational networks including Argo, Global Drifter Program, and FluxNet.

Key concepts and conventions

Core concepts include standardized variable names drawn from community vocabularies, coordinate types (time, latitude, longitude, vertical), conventions for units traceable to systems like International System of Units, and attributes capturing provenance relevant to organizations such as National Science Foundation, European Research Council, Lawrence Berkeley National Laboratory, and research programs at NOAA and NASA. Conventions for dimensions, bounds, and cell methods intersect with work by standards bodies like ISO 19115 and interoperability efforts by Open Geospatial Consortium, while naming and semantics draw on ontologies and vocabularies developed in collaborations involving Wikidata community, Research Data Alliance, and university consortia.

Implementation and tools

Tooling ecosystems include libraries and applications from Unidata such as NetCDF Operators (NCO), scientific stacks like xarray, CFUnits, and utilities integrated into platforms from ESGF (Earth System Grid Federation), PANGAEA, and modeling centers such as ECMWF and NOAA Geophysical Fluid Dynamics Laboratory. Data portals and workflow systems at institutions like NASA Earthdata, Copernicus Climate Change Service, NOAA National Centers for Environmental Information, JPL, and cloud providers collaborating with Microsoft and Amazon Web Services support CF-compliant datasets; converters and validators are provided by community projects and research groups at University of California, San Diego, Princeton University, and ETH Zurich.

Adoption and applications

Adoption spans climate model intercomparison projects coordinated by World Climate Research Programme and CMIP (Coupled Model Intercomparison Project), satellite retrieval archives managed by NASA, ESA, and JAXA, oceanographic deployments like Argo, and regional forecasting and hydrology services at UK Met Office, NOAA National Weather Service, Australia Bureau of Meteorology, and research initiatives at Scripps Institution of Oceanography and Woods Hole Oceanographic Institution. CF metadata supports data assimilation systems used by ECMWF and NCEP, reanalysis products, and interdisciplinary studies funded by agencies including National Science Foundation and European Commission.

Governance and maintenance

Maintenance and community governance are overseen by committees and working groups involving stakeholders from Unidata, World Climate Research Programme, EU Copernicus, national agencies like NOAA, NASA, ECMWF, and academic partners such as University of Reading and University of California, Los Angeles. Versioning, errata, and extensions are managed through open processes involving mailing lists, issue trackers hosted by consortia and repositories at organizations including GitHub, with periodic reviews at conferences like American Geophysical Union and workshops sponsored by Research Data Alliance and Open Geospatial Consortium.

Category:Climate data standards