Værdata

Værdata refers to observation-based and model-produced information about the state of the atmosphere and related environments. It includes measurements of temperature, precipitation, wind, humidity, pressure, cloud cover, solar radiation, soil moisture, and ocean conditions. Værdata are collected by networks of meteorological stations, upper-air measurements, radar, satellites, ships and buoys, and by numerical weather prediction models and reanalysis products. They are used for weather forecasts, climate monitoring, and research.

Data sources and collection include ground-based stations, radiosondes, weather radars, satellite sensors, ships and ocean buoys, and airborne platforms. Observations may be direct measurements or derived products such as reanalysis. Data are standardized by the World Meteorological Organization and national meteorological and hydrological services. Common formats include BUFR, GRIB, and NetCDF, and data are distributed through portals, FTP or HTTP servers, and APIs. Metadata describe quality, provenance, units and uncertainties.

Quality control and access: Data undergo quality control to identify errors and inconsistencies, with quality flags and metadata describing limitations. Access policies vary: some værdata are openly available under open-data licenses, others are restricted to users or partner organizations.

Applications: Værdata support weather forecasting, climate monitoring, aviation, maritime operations, agriculture and energy planning, and disaster management. Beyond immediate forecasts, historical and reanalysis data enable climate research and model validation.

Notable providers and standards: National meteorological services, European Centre for Medium-Range Weather Forecasts, NOAA, NASA, and EUMETSAT contribute data and model outputs. The World Meteorological Organization coordinates international standards and data exchange, promoting interoperability through formats like BUFR, GRIB, and NetCDF.