Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Inversion strategy 4D-var method adjoint model of TM3 CH4-only version has been developed optimize surface fluxes and initial CH4 field expected: in the beginning adjustments to CH4 field, later to surface fluxes time frame: 1 week to 1 month

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May D var (1)

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 cost function 4D var (2) background error covariance observation error covariance observatio n observatio n operator model state vector x = [c,...] control vector

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May D var (3) gradient of the cost function adjoint model

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Preconditioning S diagonal matrix with standard deviations LL T symmetric matrix with correlations

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 First experiments First week of January 2000 Sat.obs. taken from perturbed model run Optimize emissions only Background error covariance Standard deviation: 50% of emission Horizontal correlation function: Gaussian with length scale of 1000 km Observation error covariance Diagonal; standard deviation: 0.5% of column

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 A priori emissions

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Perturbed run 50% enhanced emissions

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Effect on CH4 field after one week

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Pseudo satellite observations

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Optimized CH4 emissions

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Resulting CH4 field

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Setting  obs to 2%

Methane inversion from satellite, TRANSCOM meeting, Jena,12-15 May 2003 Adding 0.5% noise to sat.data