Carbon accounting in Europe
In order to understand how increasing emissions of carbon dioxide (CO2) are going to affect the global climate, it is necessary to fully comprehend the global carbon cycle. However, it is practically impossible to measure the flux of carbon from the biosphere to the atmosphere, especially over a large area like the European Union. Scientists therefore rely on remote sensing and modelling. In order to improve the accuracy of these less than perfect techniques, the Max Planck Institute of Biochemistry designed a Carbon Cycle Data Assimilation System (CCDAS). They joined forces with the UK Met Office and seven other institutes in the CAMELS project funded by the Fifth Framework Programme. The CCDAS consists of a methodology for preparing and incorporating satellite measurements of surface vegetation into a Terrestrial Ecosystem Model (TEM). The TEM's surface parameterisation, specifically the Met. Office Surface Exchange Scheme (MOSES) and the Joint UK Land Environment Simulator (JULES), produce estimates of the corresponding fluxes of carbon between the biosphere and the atmosphere. In addition, a second approach was implemented whereby an Atmospheric Global Climate Model (AGCM) was tweaked to produce the observed levels of atmospheric CO2. This provided insight into the strength of specific carbon sources and sinks. The experience gathered by the Max Planck Institute of Biochemistry during CAMELS led them to the conclusion that while these inversion techniques are transparent and can be applied at the scale of the European Union, some obstacles remain. For instance, the CO2 monitoring network is not sufficiently dense enough. Furthermore, estimates of CO2 sequestration due to changes in land use (e.g. forestation projects) cannot yet be properly estimated. However, the ability to determine the net CO2 flux does represent significant progress.
