AIRS Satellite Mid-Tropospheric CO2 Gridded Retrievals

AIRS/Aqua L3 8-day CO2 in the free troposphere provides mid-tropospheric carbon dioxide concentration data from the Atmospheric Infrared Sounder and Advanced Microwave Sounding Unit instruments on NASA's Aqua satellite. The dataset consists of 8-day gridded retrievals at a 2.5x2 degree resolution, covering latitudes from -60.0 to +90.0 degrees. Each grid cell contains mean CO2 mole fraction, standard deviation, and a count of contributing individual retrievals.

Use Cases

• Analyzing spatial patterns of mid-tropospheric CO2 concentrations using the gridded mean values.
• Assessing data reliability for specific regions by examining the standard deviation and input count maps per grid cell.
• Tracking changes in atmospheric CO2 over time by comparing sequential 8-day gridded periods.
• Integrating satellite CO2 data with ground-based measurements for validation studies.
• Mapping global CO2 distribution for climate model initialization or educational visualizations.

Strengths

• Data is derived from a sophisticated instrument suite (AIRS grating spectrometer with R=1200, combined with AMSU and HSB).
• Provides three layers of information per grid: mean CO2, standard deviation, and a count of input retrievals.
• Offers consistent global coverage from -180.0 to +180.0 degrees longitude and -60.0 to +90.0 degrees latitude.

Limitations

• Specific row count, file size, and column names are not provided by any source.
• Sources disagree on the last updated date: NASA Earthdata lists 2012-02-25, while Data.gov lists 2026-03-13.
• The license is unclear; NASA Earthdata lists it as unknown, while Data.gov lists 'other-license-specified'.

Provenance

Source

GES_DISC (NASA)

Collection Method

Satellite remote sensing via AIRS and AMSU instruments on the Aqua platform, with retrievals averaged and binned into 2.5x2 degree grids.

Time Range

Each file covers an 8-day period; overall temporal coverage is not specified.

Freshness

2026-03-13 19:05:57.190663

Geography

Global, from -180.0 to +180.0 deg longitude and -60.0 to +90.0 deg latitude.