This data set contains net fluxes at the surface, atmospheric mixing ratios at model levels, for carbon dioxide (CO2), methane (CH4) and nitrous oxide (N20).
Ground-based and satellite remote-sensing observations provide a means to quantifying the net fluxes between the land and ocean on the one hand and the atmosphere on the other hand. This is done through a process called atmospheric inversion, which uses transport models of the atmosphere to link the observed concentrations of CO2, CH4 and N2O to the net fluxes at the Earth's surface. By correctly modelling the winds, vertical diffusion, and convection in the global atmosphere, the observed concentrations of the greenhouse gases are used to infer the surface fluxes for the last few decades.
The data sets for the three species was updated once or twice per year adding the most recent year to the data record, while re-processing the original data record for consistency. This is reflected by the different version numbers. In addition, fluxes for methane are available based on surface air samples only or based on a combination of surface air samples and satellite observations.
For the updated version please have a look at CAMS global inversion-optimised greenhouse gas fluxes and concentrations dataset available on the Atmosphere Data Store (ADS).