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OCO2_v11mip
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The OCO-2 v11 MIP

The Orbiting Carbon Observatory-2 (OCO-2) model intercomparison project (MIP) is a collaboration among atmospheric CO2 modelers to study the impact of assimilating OCO-2 retrieval data into atmospheric inversion models.


Protocol details available on the downloads page.

Modelers submitting global flux inversion results to the OCO-2 v11 MIP are given in Table 1, along with their transport model, meteorology source, inversion method, and the status of their model cosamples. Click the submission name to see a revision history.
Table 1. OCO-2 v11 MIP participants and model details. Last updated 2026-03-31
Cosample Status
Model Contact Institution Transport Model Meteor-ology Inverse Method ObsPack TCCON OCO-2 OCO-3 Version Revision Notes
Ames Matthew Johnson and Sajeev Philip NASA Ames Research Center GEOS-Chem MERRA-2 4D-Var ✅ ✅ ✅ ✅ 1 1
CAMS Frédéric Chevallier LSCE France LMDz-Dispersion ERA5 via LMDz Variational ✅ ✅ ✅ ✅ 1 1
CMS-Flux Junjie Liu NASA JPL GEOS-Chem MERRA-2 4D-Var ✅ ✅ ✅ ✅ 3 1
CMS-MFlux Kevin Bowman NASA JPL ✅ ✅ ✅ ✅ 1 1
CT Andy Jacobson University of Colorado and NOAA GML TM5-zoom ERA5 EnKF ✅ ✅ ✅ ✅ 2 1
CTE-FMI Aki Tsuruta Finnish Meteorological Institute TM5-MP ERA5 EnKF ❌ ❌ ❌ ❌ 1 1
GCAS Fei Jiang Chinese Academy of Sciences GEOS-Chem MERRA-2 NLS-4DVar ❌ ❌ ❌ ❌ 2 1 Neg. bias at SPO; worse fit to global growth rate
GONGGA Zhe Jin Nanjing University MOZART-4 model GEOS5 EnKF ❌ ❌ ❌ ❌ 1 1 Neg. bias at SPO; worse fit to global growth rate
JHU Kristan Morgan and Scot Miller Johns Hopkins University GEOS-Chem MERRA-2 Geostatistical ✅ ✅ ✅ ✅ 3 1
NISMON-CO2 Suman Maity and Yosuke Niwa National Institute for Environmental Studies (NIES) NICAM-TM JRA-3Q 4D-Var ✅ ✅ ✅ ✅ 1 1 LNLG v2
NTFVAR Shamil Maksyutov and Rajesh Janardanan Satellite Observation Center, National Institute for Environmental Studies (NIES) NIES-TM and FLEXPART ERA5 and JRA-55 Variational ✅ ✅ ✅ ✅ 1 1
PCTM David Baker Colorado State University PCTM MERRA-2 4D-Var ✅ ✅ ✅ ✅ 2 2 Cosamples soon
TM5-4DVAR Sourish Basu University of Maryland and NASA GMAO TM5 ERA5 4D-Var ✅ ✅ ✅ ✅ 1 2
WOMBAT-GC Michael Bertolacci, Andrew Schuh, and Andy Jacobson University of Western Australia and Colorado State University GEOS-Chem MERRA2 Hierarchical Bayesian ✅ ✅ ✅ ✅ 2 1 TCCON issue
WOMBAT-TM5 Michael Bertolacci, Andy Jacobson, and Andrew Schuh University of Western Australia and University of Colorado TM5 ERA5 Hierarchical Bayesian ✅ ✅ ✅ ✅ 2 1 underway

Inversion experiments

Modelers performed inversion experiments assimilating various types of observational constraints. These experiments extend from the beginnning of the OCO-2 retrievals in September 2014 through the end of 2024. Results are reported for the 10-year interval 2015-2024.

  • IS: Assimilation of in situ CO2 measurements
  • LNLG: Assimilation of OCO-2 Land Nadir and Land Glint retrievals
  • LNLGIS: Assimilation of OCO-2 Land Nadir and Land Glint retrievals, and in situ CO2 measurements
  • LNLGOGIS: Assimilation of in situ CO2 measurements and all OCO-2 retrievals