caa a22 4500 475777204 CHVBK 20180406123634.0 cr unu---uuuuu 170329e20000801xx s 000 0 eng 10.1023/A:1002604505377 doi (NATIONALLICENCE)springer-10.1023/A:1002604505377 Verifying Inventory Predictions of Animal Methane Emissions with Meteorological Measurements [Elektronische Daten] [O. Denmead, R. Leuning, D. Griffith, I. Jamie, M. Esler, L. Harper, J. Freney] The paper examines the strengths and weaknesses of a rangeof meteorological flux measurement techniques that mightbe used to verify predictions of greenhouse gas inventories.Recent research into emissions of methane (CH4)produced by enteric fermentation in grazing cattle and sheepis used to illustrate various methodologies. Quantifying thisimportant source presents special difficulties because the animalsconstitute moving, heterogeneously distributed, intermittent, pointsources. There are two general approaches: one, from the bottom up,involves direct measurements of emissions from a known number ofanimals, and the other, from the top down, infers areal emissions ofCH4 from its atmospheric signature. A mass-balance methodproved successful for bottom-up verification. It permits undisturbedgrazing, has a simple theoretical basis and is appropriate for fluxmeasurements on small plots and where there are scattered pointsources. The top-down methodologies include conventional flux-gradientapproaches and convective and nocturnal boundary-layer (CBL and NBL)budgeting schemes. Particular attention is given to CBL budget methods inboth differential and integral form. All top-down methodologies require ideal weather conditions for their application, and they suffer from the scattered nature of the source, varying wind directions and low instrument resolution. As for mass-balance, flux-gradient micrometeorological measurements were in good agreement with inventory predictions of CH4 production by livestock, but the standard errors associated with both methods were too large to permit detection of changes of a few per cent in emission rate, which might be important for inventory, regulatory or research purposes. Fluxes calculated by CBL and NBL methods were of the same order of magnitude as inventory predictions, but more improvement is needed before their use can be endorsed. Opportunities for improving the precision of both bottom-up and top-down methodologies are discussed. Kluwer Academic Publishers, 2000 Mass balance nationallicence Flux-gradient nationallicence Boundary-layer budgeting nationallicence Enteric fermentation nationallicence Denmead O. F.C. Pye Laboratory, CSIRO Land and Water, Canberra, ACT, Australia aut Leuning R. F.C. Pye Laboratory, CSIRO Land and Water, Canberra, ACT, Australia aut Griffith D. Department of Chemistry, University of Wollongong, Wollongong, NSW, Australia aut Jamie I. Department of Chemistry, University of Wollongong, Wollongong, NSW, Australia aut Esler M. Department of Chemistry, University of Wollongong, Wollongong, NSW, Australia aut Harper L. Southern Piedmont Conservation Research Unit, USDA-Agricultural Research Service, Watkinsville, GA, U.S.A. aut Freney J. CSIRO Plant Industry, Canberra, ACT, Australia aut Boundary-Layer Meteorology Kluwer Academic Publishers 96/1-2(2000-08-01), 187-209 0006-8314 96:1-2<187 2000 96 10546 https://doi.org/10.1023/A:1002604505377 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1002604505377 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Denmead O. F.C. Pye Laboratory, CSIRO Land and Water, Canberra, ACT, Australia aut NATIONALLICENCE 700 1- Leuning R. F.C. Pye Laboratory, CSIRO Land and Water, Canberra, ACT, Australia aut NATIONALLICENCE 700 1- Griffith D. Department of Chemistry, University of Wollongong, Wollongong, NSW, Australia aut NATIONALLICENCE 700 1- Jamie I. Department of Chemistry, University of Wollongong, Wollongong, NSW, Australia aut NATIONALLICENCE 700 1- Esler M. Department of Chemistry, University of Wollongong, Wollongong, NSW, Australia aut NATIONALLICENCE 700 1- Harper L. Southern Piedmont Conservation Research Unit, USDA-Agricultural Research Service, Watkinsville, GA, U.S.A aut NATIONALLICENCE 700 1- Freney J. CSIRO Plant Industry, Canberra, ACT, Australia aut NATIONALLICENCE 773 0- Boundary-Layer Meteorology Kluwer Academic Publishers 96/1-2(2000-08-01), 187-209 0006-8314 96:1-2<187 2000 96 10546 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer