Using ecosystem manipulation data for Model-Data-Fusion of a generic vegetation model

T. Thum1), P. Peylin2), A. Ibrom3), L. van der Linden3), P. Ciais2)

1)Finnish Meteorological Institute, Helsinki, Finland
2)LSCE, Gif-Sur-Yvette, France
3)Risø DTU, Roskilde, Denmark

In ecosystem manipulation experiments (EMEs) the ecosystem is artificially exposed to different environmental conditions. At Danish EME site Brandbjerg the responses of a shrubland to drought, warming and increased atmospheric CO2 concentration are studied. These experiments provide excellent data for validation and development of ecosystem models. In this work we used generic vegetation model ORCHIDEE, that is used also in global scale simulations, with Model-Data-Fusion (MDF) approach. In MDF we are using observations from the site to optimize the model parameters. This enables us to assess the modelling errors and the performance of the model for different treatments. This insight will inform us whether the different processes are adequately modelled or if some important processes are missing. The preliminary results suggest that a new plant functional type need to be developed to ORCHIDEE in order to successfully simulate the Brandbjerg site.