Skip to main content

GEOS-5 Atmospheric Composition Reanalysis

By assimilating aerosol and trace gas concentrations, this SNWG solution improves the GEOS-Composition Forecasting (CF) system's representation of atmospheric composition.

Background

Aerosol and trace gas concentrations observed by satellites and ground stations will be assimilated in the Goddard Earth Observing System (GEOS) model. This will provide global, three-dimensional gridded atmospheric composition distributions for the period 2008-2018. Fields for 2008-2018 will be provided, based on the GEOS-CF (Composition Forecasting) system.

Status: In Development

The GEOS-CF system has been enhanced and final testing is being completed before product generation begins. Retaining the 72-layer, 25-km configuration, the updated GEOS model is being run with assimilation of atmospheric constituents (aerosols, ozone, nitrogen dioxide (NO2), and carbon monoxide (CO)) from a variety of observation sources. Testing and benchmarking of this system is underway. Once the system evaluation is complete, the reanalysis products for the 2008-2018 will be generated. 

The reanalysis products are expected to be available by late 2026. The bulk of the work has been on preparation for the assimilation of the multiple input datasets, implementation and evaluation of the NO2 assimilation, and the development of new monitoring and evaluation diagnostics, tested on the Global Modeling and Assimilation Office’s (GMAO) real-time GEOS-CF system. These diagnostics are released daily on the GMAO’s web site.

Solution Characteristics

Platforms and InstrumentsAura: Ozone Monitoring Instrument (OMI), Microwave Limb Sounder (MLS)
Aqua: Atmospheric Infrared Sounder (AIRS)
Greenhouse Gases Observing SATellite (GOSAT): Thermal And Near infrared Sensor for carbon Observation (TANSO)- Cloud and Aerosol Imager (CAI), TANSO-Fourier Transform Spectrometer (FTS)
International Space Station (ISS): Sage III
Orbiting Carbon Observatory-2 (OCO-2): Spectrometers
Sentinel-5 Precursor: TROPOspheric Monitoring Instrument (TROPOMI)
Suomi National Polar-orbiting Partnership (Suomi NPP), NOAA-20/21: Ozone Mapping and Profiler Suite (OMPS), Cross-track Infrared Sounder (CrIS)
Terra: Measurements of Pollution In The Troposphere (MOPITT)
Output VariablesReanalysis of NO2, O3, CH4, CO2, CO, HCl, HNO3, N2O, H2O
Temporal Coverage2008-2018
Spatial CoverageGlobal
Spatial Resolution25 km
Vertical Resolution72 layers, surface to mesosphere
Data FormatNetCDF4 (HDF5 compatible)

Societal Impact

Assimilation of additional aerosol and trace gas concentration data is improving the GEOS-CF system’s representation of atmospheric composition, with benefits ranging from historical reanalysis of trends and outlier events to improved forecasts for air quality monitoring and pollution regulation.

Solution Resources

Need help using this Satellite Needs Working Group (SNWG) solution? For more information, visit GMAO - GEOS-CF.