File : D4.8
Author : Rona Thompson (NILU)
This deliverable presents the results of inverse modelling of CH4 and N2O. Emissions of CH4 were estimated using the FLEXPART-ExKF inversion framework, which employs an Extended Kalman Filter (ExKF) and uses the Lagrangian Particle Dispersion Model, FLEXPART to model atmospheric transport (see Section 4.1.2). Emissions of N2O were estimated using the FlexInvert inversion framework, which finds the maximum posterior probability solution using Bayesian statistics and also employs the FLEXPART transport model (see Section 4.1.2). For both CH4 and N2O, the emissions are presented at 0.5°×0.5° resolution and at a minimum of monthly temporal resolution for the period 2005-2018. The inversion finds slightly lower CH4 emissions over Europe compared to the prior, but both prior and posterior estimates show a small negative trend over 2005-2018. For N2O the inversion finds higher emissions compared to the prior and to UNFCCC. The inversion also shows a negative emission trend from 2013.
Figure 1 : Monthly mean total EU28 emissions over the period 2005-2018
