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.

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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.

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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	✅	✅	✅	✅
CMS-MFlux	Kevin Bowman	NASA JPL				❌	❌	❌	❌
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	⚠️	❌	❌	❌
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

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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