Joint EPMAN and TFEIP Expert Panel meeting Berlin, September 28, 2012 EAGER Network

EAGER: European Agricultural Gaseous Emissions Inventory Researchers Network Background Accurate and reliable inventories of NH3 emissions are increasingly important In the past different national inventories were not comparable due to different methods used A core group of emission inventory experts initiated EAGER to achieve a detailed overview of present best available inventory techniques initiate a new generation of emission inventories Network founded in 2003; 1-2 workshops per year

EAGER: European Agricultural Gaseous Emissions Inventory Researchers Network Key tasks Comparison of models: how far do results agree; reasons for differences? Liquid manure system dairy cows, fattening pigs (paper) Solid manure systems beef cattle, broilers (paper) Review of published and unpublished data on emission factors for NH3, N2O and CH4 for solid manure (paper) Analysis of NH3 emissions per unit product (milk, beef, pork, broiler, eggs) in different countries (ongoing) Exchange on ongoing and new activities

Approach for comparison of models Six N-flow models from DE, DK, NL, UK, CH used for emission inventories Mass flow approach with animal specific excretion rates N/TAN flow of through different stages of the manure handling chain is simulated Emissions are calculated with emission factors expresses in percentage of the TAN present a specific stage of emission Effects of emissions that occur in the upstream part of the manure management system on emissions on the subsequent downstream parts can be easily taken into account

Models used for the comparison

Approach for comparison of models (2) Three levels of model standardizations Liquid manure system: A simplified dairy cow and pig scenario (only dairy scenario presented here) Solid manure system: Beef cattle and broiler scenarios

Results and discussion: FF scenario liquid Very similar estimates of the NH3 emissions for the FF scenario  underlying N flows of the different models are highly comparable

Results and discussion: FN scenario liquid Substantial differences in emissions due to assumptions used for emission factors (EF), e.g.: Lowest N-fertilization of pastures for DYNAMO Solid floor housing systems in UK DYNAMO assumes constant emissions per m2 during partial grazing Broadcast application banned in NL  EF not up to date

Results and discussion: FN scenario liquid "Philosophy" behind the model can also influence the results Example Switzerland: change from DYNAMO to Agrammon in 2009 Emission factors DYNAMO: best estimate standard production Emission factors Agrammon: "Worst case" assumption Higher emissions for housing and storage Agrammon

Results and discussion: NN scenario liquid More substantial differences between results than FN scenario Variation primarily result from distinct national emission factors and N excretion rates which reflect the specific livestock and manure management systems and climatic conditions Similar conclusions for pig scenario

Conclusions liquid manure scenarios Very similar estimates of the NH3 emissions were obtained for the FF scenario indicating that the underlying N flows of the different models are highly comparable Differences were more pronounced when the emissions were calculated with national emission factors and/or national N excretion rates (FN and NN scenarios) The variation in the calculated emissions for the FN and NN scenarios was primarily the result of the distinct national emission factors and N excretion rates which reflect the specific livestock and manure management systems and the specific climatic conditions of the countries Weaknesses of all models recognized and improved thanks to the comparison exercise

Results solid manure scenarios (Beef cattle) FF FN NN Much larger variability than for slurry scenarios Limited data available; big gaps and uncertainties in knowledge for important processes influencing the ammonia losses Immobilization and mineralization processes more important Larger differences in production systems between the different countries

General conclusions of the EAGER Network model comparison activities Thorough and critical analysis of models and intensive exchange between participants  weaknesses of all models recognized and improved all partners and models profited from the exercise harmonization between calculation procedures started Evidence of good comparability between N-flow models Indication that models are following the same general procedure and are based on comparable data and assumptions Relatively good agreement for slurry scenarios, the variation is much higher for solid manure scenarios

Publications EAGER Network Reidy B., Dämmgen U., Döhler H., Eurich-Menden B., van Evert F.K., Hutchings N.J., Luesink H.H., Menzi H., Misselbrook T.H., Monteny G.-J., Webb J., 2008. Comparison of models used for national agricultural ammonia emission inventories in Europe: liquid manure systems. Atmospheric Environment, 42, 3452-3464 Reidy B., Webb J., Misselbrook T.H., Menzi H., Luisink H.H., Hutchings N.J., Eurich-Menden B., Döhler H. Dämmgen U., 2009. Comparison of models used for national agricultural ammonia emission inventories in Europe: litter-based manure systems. Atmospheric Environment, 43, 1632-1640 Webb J, Sommer SG, Kupper T, Groenstein CM, Hutchings N, Eurich- Menden B, Rodhe L, Misselbrook T, Amon B, 2011. Emissions of Ammonia, Nitrous Oxide and Methane During the Management of Solid Manures. In: Agroecology and Strategies for Climate Change. Sustainable Agriculture Reviews 12. Springer, 67–107

Relationship of EAGER to EPMAN and TFEIP Expert Panel EAGER is not competing but supplementing and supporting EPMAN and TFEIP Expert Panel TFEIP Expert Panel focusses on emission inventory work “tier 1 and 2 level“ EAGER focuses on emission inventory work “tier 3 level“ EPMAN focuses on mitigation options TFRN focuses on whole N-cycle strategies EAGER members actively participate in TFRN/EPMAN/TFEIP/WGSR work