For the purpose of reporting GHG emissions and removals from anthropogenic activities in Agriculture, Forestry and Other Land Use (AFOLU) under the UNFCCC, the Intergovernmental Panel on Climate Change (IPCC) provides in the 2006 IPCC Guidelines that it is good practice to use managed land as a proxy for anthropogenic emissions and removals.
For the years 2013-2020 Decision No 529/2013/EU of the European Parliament and of the Council extended mandatory accounting for Greenhouse Gas (GHG) emissions and removals to the activities Cropland Management (CM) and Grazing Land Management (GM) for the Member States of the European Union.
The 2006 IPCC Guidelines distinguish three tiers of methods, of which Tier 1 is the most generic. Tier 1 uses general default values and national data for estimating carbon stock changes and non-CO2 GHG emissions. For the purpose of accounting under the Kyoto Protocol land use conversions leading to GHG emissions from the soil should be spatially explicit (Approach 3).
A processing environment following the IPCC guidelines for a Tier 1 method and Approach 3 was developed at the JRC to estimate CO2 emissions and removals from changes in soil organic carbon (SOC) stocks as a consequence of changes in land use, management practice and input level. The implementation uses statistical data to establish the annual status and a range of ancillary data to estimate transitions between years. A comparison between the results obtained and the trends related in the annual reports provided by EU Member States led to the conclusion that the data on land use was a major source of differences between the estimated and reported in the trends of CO2 emissions and removals from the soil. These differences will decide the trend of any estimates, regardless of the IPCC Tier used.
As a consequence, the procedure implemented to generate a complete time-series of statistical data was investigated and revised. Particular attention was paid to the process of integrating data coming from different sources into a single set. The degree to which data from different sources agree varies from complete agreement to opposing trends. The procedure for generating a more consistent single time-series combines a hierarchical structure for combining data with a statistical analysis for detecting outliers, but not changing any trends.
The new input data was employed to re-process changes in soil organic carbon stocks from 1970 to the statistical data available on land use in 2018. Although all EU Member States are processed starting with 1970, the publicly available source data on land use would allow a 1990 baseline for reporting CO2 emissions and removals for 18 countries using national data, but only 8 countries using data at NUTS Level 2. In the sources used 5 countries are reported with detailed data only for 2005 later years.JRC.D.3-Land Resource
