Our Data Access page has a list of options. If you want to look at visualizations of the latest forecasts, we recommend going to the FLUID page for GEOS-CF. If you want to download forecast data for a specific location, the CFAPI is an efficient option; please contact us if you would like access to the API. If you need access to the full data files, these are available on the NCCS Data Portal.

Data from the initial version of the GEOS-CF system are available starting January 1st, 2018. Data from GEOS-CF v2 are available starting August 4th, 2025.

The GEOS-CF file specifications on the Documentation page have complete lists of the available products. These include aerosol and trace gas constituents and their emissions, along with meteorological information. Different outputs are available at the model surface layer, on pressure and model vertical levels, and as column-integrated values. Different outputs are also available as hourly average, hourly instantaneous, and 15-minute instantaneous temporal frequencies.

The ‘aqc’ collection includes common outputs relevant to air quality: near-surface NO2, O3, SO2, CO, PM2.5, and PM10 concentrations. Please note that GEOS-CF is a research product and is not suitable for assessing compliance with air quality regulations such as the USA Clean Air Act.

The data assimilation cycle is started each day at 9:00 UTC. The complete process (analysis and five-day forecast) usually takes about 8 hours. Thus, the forecasts are usually available by about 17:00 UTC the same day. Forecast files can be accessed as soon as they become available via the NCCS Data Portal; other access methods are only enabled after the full forecast is completed. Any delays will be announced via the GEOS-CF users email list.

Due to the large size of GEOS-CF data files, we are only able to provide forecasts files publicly for the aqc collection since the start of the data record. For other collections, forecasts are only available for the last 14 days. 

The updates to the GEOS-CF system include updates to the GEOS atmospheric general circulation model and the GEOS-Chem chemical model, replaying meteorology to GEOS IT, direct assimilation of stratospheric profiles and column ozone, and updates to the anthropogenic emission source. Many of the same products are available, and some new products have been added, but other products have been discontinued. The current GEOS-CF system (v1) is running in near-real time through mid-October 2025, at which point the updated system (v2) will become the main GEOS-CF product, and the current version will lose its priority on our computer systems and may run on a delayed schedule. Please also note that following this date, OPeNDAP output (https://opendap.nccs.nasa.gov/dods/gmao/geos-cf/) from the current ‘assim' and ‘fcast’ paths will be moved into a ‘v1’ directory. Please refer to the file specification for a more complete description of these changes.