File : D4.10
Author : Isabelle Pison (LSCE)
This deliverable presents the CH4 and N2O fluxes obtained by atmospheric inversion with the CIF interfaced with different atmospheric chemistry-transport models (FLEXPART, FLEXPART-EMPA, and CHIMERE). The fluxes were estimated over the European domain (15°W to 35°E and 33°N to 73°N) for the years 2006 to 2018 from all models.
For CH4, the results from CHIMERE differed somewhat from the two FLEXPART models in where the posterior fluxes departed from the prior estimates, but were reasonably comparable in terms of the annual emissions at regional scales. For EU27 plus Norway, Switzerland and UK (EU27+3), the total mean emissions were 26, 22 and 24 Tg CH4/y, for CHIMERE, FLEXPART and FLEXPART-EMPA, respectively.
For N2O, inversions were run with CHIMERE and FLEXPART (NILU). The results using the two models were very comparable at the level of EU27+3 with annual mean emissions for 2005-2018 of 0.98 and 1.07 TgN/y and with decreasing trends of 0.010 and 0.019 TgN/y per year for CHIMERE and FLEXPART, respectively.
