Version 11.0 is the current version of the Atmospheric Carbon Observations from Space (ACOS) retrieval product as applied to the Greenhouse Gases Observing Satellite (GOSAT) as part of close partnership between The Orbiting Carbon Observatories (OCO) and GOSAT. Older versions will no longer be available and are superseded by Version 11.0.

The ACOS Lite files contain bias-corrected column-integrated dry air mole fraction of carbon dioxide (XCO2) along with other select fields aggregated as daily .nc4 files with 10.5km x 10.5km spatial resolution. The last version of this product was ACOS/GOSAT version 9 (Taylor et al., 2020), and covered the time period 2009/04/20-2020/06/30. The v11.0 product uses the latest version of the ACOS algorithm and covers 2009/04/18-2025/03/26, containing XCO2 (units of parts per million [ppm]) for nearly clear-sky soundings with sufficient signal, over both land and ocean. This product uses TANSO-FTS instrument's spectral radiances as produced by JAXA, version v300300 and v300301.

The GOSAT team at JAXA produces GOSAT TANSO-FTS Level 1B (L1B) data products for internal use and for distribution to collaborative partners, such as ESA and NASA. These calibrated products are augmented by the OCO Project with additional information such as local surface elevation. Thus produced Level 1B products (with calibrated radiances and geolocation) are the input to the ACOS Level 2 production process. The ACOS version 11.0 product was produced at Colorado State University.