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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.
Table 1. OCO-2 v11 MIP participants and model details.
Cosample Status
Model Contact Institution Transport Model Meteor-ology Inverse Method ObsPack TCCON OCO-2 OCO-3 Notes
Ames Matthew Johnson and Sajeev Philip NASA Ames Research Center GEOS-Chem MERRA-2 4D-Var Cosamples not submitted
CAMS Frédéric Chevallier LSCE France LMDz-Dispersion ERA5 via LMDz Variational ⚠️ TCCON obs_num issue
CMS-Flux Junjie Liu NASA JPL GEOS-Chem MERRA-2 4D-Var
CT Andy Jacobson University of Colorado and NOAA GML TM5-zoom ERA5 EnKF TCCON sampling underway
CTE-FMI Aki Tsuruta Finnish Meteorological Institute TM5-MP ERA5 EnKF ingest underway
CT-MP Andy Jacobson University of Colorado and NOAA GML TM5-MP ERA5 EnKF ⚠️ TCCON sampling underway
GCAS Fei Jiang Chinese Academy of Sciences GEOS-Chem MERRA-2 NLS-4DVar issue with submission
GONGGA Zhe Jin Nanjing University MOZART-4 model GEOS5 EnKF issue with submission
JHU Kristan Morgan and Scot Miller Johns Hopkins University GEOS-Chem MERRA-2 Geostatistical Prior fluxes missing
NISMON-CO2 Suman Maity and Yosuke Niwa National Institute for Environmental Studies (NIES) NICAM-TM JRA-3Q 4D-Var
NTFVAR Shamil Maksyutov and Rajesh Janardanan Satellite Observation Center, National Institute for Environmental Studies (NIES) NIES-TM and FLEXPART ERA5 and JRA-55 Variational
PCTM David Baker Colorado State University PCTM MERRA-2 4D-Var Currently rerunning
TM5-4DVAR Sourish Basu University of Maryland and NASA GMAO TM5 ERA5 4D-Var
WOMBAT-GC Michael Bertolacci, Andrew Schuh, and Andy Jacobson University of Western Australia and Colorado State University GEOS-Chem MERRA2 Hierarchical Bayesian ⚠️ TCCON issue
WOMBAT-TM5 Michael Bertolacci, Andy Jacobson, and Andrew Schuh University of Western Australia and University of Colorado TM5 ERA5 Hierarchical Bayesian 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