CAMS Global Atmospheric Composition Forecast

CAMS Global Atmospheric Composition Forecast is a Level-4 numerical weather prediction product from ECMWF, generated by the IFS-COMPO coupled atmospheric chemistry model. It covers more than 50 gas-phase species including O3, NO2, CO, SO2, PM2.5, and PM10, alongside seven aerosol types: desert dust, sea salt, organic matter, black carbon, sulphate, nitrate, and ammonium.^[1]

The forecast runs twice daily at 00 UTC and 12 UTC, producing a 5-day horizon at 0.4 x 0.4 degree global resolution. Output is available at 1-hourly timesteps for single-level fields and 3-hourly timesteps for multi-level profiles. Files are delivered in GRIB format with an optional netCDF conversion. The archive extends from 2015 to present.^[1]

This product is not satellite-derived. It assimilates satellite observations of atmospheric composition into a chemistry transport model, making it a model analysis and forecast product rather than a direct retrieval.^[1]

Access is free and open via the Copernicus Atmosphere Data Store (ADS) at atmosphere.copernicus.eu. The model system is upgraded approximately annually; version changelogs are tracked in ADS release notes.^[2]