| Version number | dates | Main features |
|---|
| V1, V2 | 2000-2003 |
Regression based retrievals for maps (not quantitative) |
| V3 | 2003- 2009 |
Optimal Estimation (OE) retrievals with error characterization. Accounted for loss of optical bench 1 in May 2001. (Deeter et al., JGR, 2003) |
| V4 | 2009-2012 |
Change from single, global apriori to climatology; log10(VMR) CO parameters; expanded forward model training set; Near Real Time (NRT) products. (Deeter et al., JGR, 2010) |
| V5 | 2011-2016 |
Added NIR (near-infrared) and multispectral (TIR+NIR) products; accounts for “geophysical noise”; added time dependent forward model to address instrument parameter changes. (Deeter et al., JGR, 2013, Worden et al., AnnGeo, 2014, DOI:https://doi.org/10.4401/ag-6330) |
| V6 |
2013-
2017 |
Change from NCEP to MERRA reanalysis for more accurate T, H2O parameters; fixed geolocation and updated climatology for apriori profiles. (Deeter et al., AMT, 2014) |
| V7 |
2016-
2019 |
Improved cloud detection; accounts for NO2 growth; consistent NIR calibration; optimized radiance bias correction; MERRA-2 (Deeter et al., AMT, 2017) |
| V8 |
2018-
2022 |
Time and water vapor dependent radiance bias correction accounts for drift and latitude dependence in CO VMR bias. (Deeter et al., AMT, 2019) |
| V9 |
2021 - 2025 |
Improved coverage over polluted land scenes due to revisions in cloud detection algorithm (Deeter et al., AMT, 2022) |
| V10 | Final Reprocessing | Similar to V9 with the addition of a Lower Tropospheric retrieval. The value of this new product is the stability of its algorithm, which is unaltered throughout the entire mission. Other changes include improved N2O modeling which will improve accuracy in the later years. |
