© SHL / /H. Menzi1 EAGER European Agricultural Gaseous Emissions Inventory Researchers Network Update 2007 Participants Denmark: Nick Hutchings Germany: Ulrich Daemmgen & Dieter Haenel, FAL; Helmut Doehler, KTBL; Netherlands: Gert-Jan Monteny, IMAG; F.K. van Evert, PRI; H.H. Luesink, LEI Sweden: Lena Rodhe, JTI Switzerland: Harald Menzi and Beat Reidy, SHL UK: Jim Webb, AEA Energy & Environment; Tom Misselbrook, IGER Affiliated: Zig Klimont, IIASA

© SHL / /H. Menzi2 Why EAGER ? Check comparability and reliability of existing inventory methods  quality control; improvement of methods Develop inventories suitable for reporting under the convention –Present inventories are not sufficient for time series: insufficient information on farming practice (expert assumptions); not all influencing factors considered Better harmonisation of inventory approaches –Common general approach –Comparable emission factors –Comparable presentation of results

© SHL / /H. Menzi3 Past activities Analysis of the situation and the existing problems associated with inventory making Detailed introduction of the methods developed/used by members Compilation and comparison of N excretions Compilation and comparison of emission factors Congruency testing of models for slurry systems (calculations with common model scenarios; cattle and pigs) →Paper accepted for publication in Atmospheric Environment

© SHL / /H. Menzi4 Current activities Extension of congruency testing exercise to solid manure systems (calculations with common model scenarios; beef cattle and broilers) Work still under progress Situation appeared to be even more complex than that for slurry systems N transformation processes (mineralization, immobilization) Relevance of other N losses N 2 O)

© SHL / /H. Menzi5 Congruency testing: Beef FF scenario (fixed emission factors, fixed N excretions) Bad agreement of total emissions and emissions from individual emission stages What are the reasons?

© SHL / /H. Menzi6 Congruency testing: Beef FF scenario (fixed emission factors, fixed N excretions) Agreement is much better if immobilization of TAN in bedding material and other N losses are accounted for Models differ highly to the extend these processes are taken into account Significance of N immobilization and other N losses

© SHL / /H. Menzi7 Conclusions for solid manure scenarios Individual models differ highly with respect to the degree immobilisation of TAN and other N losses (N 2 O) are accounted for If these two processes are included in the comparisons, the different models generally compare very well Variation of NH 3 emissions is much higher than for slurry systems Need for a better understanding of the size of other N losses and the role of N transformation processes

© SHL / /H. Menzi8 Conclusions after 4 years of EAGER 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 –Starting harmonization between calculation procedures 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, variation is much higher for solid manure scenarios