Mesoscale inversion: first results from the CERES campaign with synthetic data

T. Lauvaux (1, 2, 3) , M. Uliasz (4) , C. Sarrat (3) , F. Chevallier (1, 2) , Philippe Bousquet (1, 2) , C. Lac (3) , K. Davis (5) , Philippe Ciais (1, 6) , A. Denning (7) , P. Rayner (1)

1 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
2 SATINV - Modélisation INVerse pour les mesures atmosphériques et SATellitaires
3 CNRM - Centre national de recherches météorologiques
4 Department of Atmospheric Science [Fort Collins]
5 Penn State - Pennsylvania State University
6 ICOS-ATC - ICOS-ATC
7 CSU - Colorado State University [Fort Collins]

We investigate the ability of a mesoscale model to reconstruct CO2 fluxes at regional scale. Formally, we estimate the reduction of error for a CO2 flux inversion at 8 km resolution in the South West of France, during four days of the CarboEurope Regional Experiment (CERES) in spring 2005. Measurements from two towers and two airplanes are available for this campaign. The lagrangian particle dispersion model LPDM was coupled to the non-hydrostatic model Meso-NH and integrated in a matrix inversion framework. Impacts of aircraft and tower measurements are quantified separately and together. We find that the configuration with both towers and aircraft is able to significantly reduce uncertainties on the 4-day averaged CO2 fluxes over about half of the 300×300 km domain. Most of this reduction comes from the tower measurements, even though the impact of aircraft measurements remains noticeable. The noise contributed by imperfect knowledge of boundary inflows does not significantly impair the resolution. We test alternative strategies to improve the impact of aircraft measurements and find that most information comes from measurements inside the boundary layer.

Domains: Ocean, Atmosphere; Continental interfaces, environment

T. Lauvaux, M. Uliasz, C. Sarrat, F. Chevallier, Philippe Bousquet, et al.. Mesoscale inversion: first results from the CERES campaign with synthetic data. Atmospheric Chemistry and Physics, 2008, 8 (13), pp.3459-3471. ⟨10.5194/acp-8-3459-2008⟩. ⟨hal-02926817⟩