CH4 inversion using CHIMERE model were performed by Antoine Berchet. 
Reference paper : Berchet et al., GMD, Objectified quantification of uncertainties in Bayesian atmospheric inversions, 2015
The run was made for year 2010 only using avaible InGOS data. Below are some specificities of the model.

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Observations:
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Only INGOS data have been assimilated = scenario S7
Use only daily mean.
Temporal series have been recontructed in the files /OBS/*_ING_000_ASSIM_SX_MARGINCHIMERE.dat
Only the highest level is used when multiple levels are available at the station.
Instrumental error and model error are not specify (put to -1), only the total error is given (dCH4_tot).
The inversion itself filters the data and uses only those which are valuable to the inversion. When not used in the inversion, the observation has a total error put to -1.
Below is the summary of the data used :
Station name;number of daily obs available; number of daily obs used in the model; prior correlation obs/mod; posterior correlation on assimilated obs; correlation on remaining obs
KAS 260 66 0.41311237317 0.708354557886 0.666544077152
JFJ 271 64 0.441146190976 0.542503425999 0.507870381026
CBW 79 26 0.863116909212 0.900942338494 0.884455882769
SCH 280 88 0.634084864076 0.771607398385 0.69682837512
TRN 263 81 0.78130806606 0.892693975779 0.872734695298
HUN 194 70 0.722416652328 0.750527441743 0.681389163171
VKV 257 87 0.441570904529 0.731463052211 0.655064238026
HEI 265 90 -0.043915437907 -0.0224192520601 0.642495303822
IPR 235 43 0.669443518523 0.677310971326 0.627122541135
GIF 279 92 -0.0682910191711 -0.0771785946856 0.892422023711
BGU 1 1 nan nan nan
OXK 115 35 0.406679110197 0.642285153889 0.547360268214
BIK 109 36 0.524364144419 0.660186116757 0.598992718227
TTA 243 100 -0.0266339542338 -0.0183783099007 0.744219496721
PAL 237 102 0.62982070885 0.685213034493 0.570855597125
MHD 312 132 -0.0106148466687 -0.00604710003184 0.834686724665
PUY 91 25 -0.249169218569 -0.246064896784 -0.305099731931

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Emissions :
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The file EU27_emis.txt contains country emissions.
HEADER: Country;PriorEmissions (Tg/y); PriorUncertainties (Tg/y); PosteriorEmissions
(Tg/y); PosteriorUncertainties(Tg/y)
Though the prior uncertainties are only pixel uncertainties summed up. The posterior correlation take spatial correlations into account. So they are not really comparable...

The Netcdf file InGOS_regular_outputs.nc contains the same variable per pixel.
Xb= prior emissions
Xa= posterior emissions
B= prior uncertainties
Pa= posterior uncertainties
KH= give an idea of the constrain if nul then Xa=Xb

