The EU greenhouse gas inventory for the LULUCF sector: I. Overview and comparative analysis of methods used by EU member states

Reporting national greenhouses gas inventories for the Land Use, Land Use Change and Forestry (LULUCF) under the United Nations Framework Convention for Climate Change (UNFCCC) has been driving significant development of national data. Lands classification and definitions for C pools are very different across the 28 EU member states, as are the methods used for data collection and processing. Even when definitions or sampling methods were in substance the same, specifications were-different. However, member states' inventories are assumed to be fully comparable and consistent with reporting principles. For forest, data collection rely on forest inventory repeated measurements (both statistical sampling and stand-wise), while for most important contributor, the biomass, there is no preference for "gain-loss" or "stock-change" method. For cropland and grasslands, operational records information is equally important to statistical sampling and aerial photography sources for area estimation, while default emission factors are used less and less as they are being replaced by country-specific data. The obvious trend is the move toward statistical sampling covering all land categories within national territory and slight increasing use of models. Such heterogeneity requires a better harmonization of data collection and processing as to increase the credibility of the EU GHG inventory.