Definition of 1A3ai International Aviation Source Category
Emissions which relate to fuel use for international civil aviation. Note that these emissions are to be excluded as far as possible from national totals but should be reported separately. (In other inventory methodologies, landing and take-off (LTO) cycle emissions are often considered as domestic emissions. For the purpose of greenhouse gas emissions inventories, fuel used during landing and take-off for an international flight stage is considered to be part of International Bunkers fuel use.)
Intergovernmental Panel on Climate Change (IPCC), Revised 1996 Guidelines for National Greenhouse Gas Inventories. Houghton, J.T., Meira Filho, L.G., Lim, B., Tréanton, K., Mamaty, I., Bonduki, Y., Griggs, D.J. and Callander, B.A. (Eds).. IPCC/OECD/IEA, 1997.
Available online at: http://www.ipcc-tfi.iges.or.jp/public/gl/invs1.html