Aircraft Exhaust Emissions (Hansard, 16 July 2004)

§ Lord Davies of Oldham:

Studies of the impacts of aircraft exhaust emissions on the upper atmosphere have been undertaken by the scientific community in the UK in collaboration with other countries for some years. Most recently, the EC TRADEOFF project looked at the potential to change the global fleet's operations in order to minimise climate change impacts. This work suggests that total impacts may be 165WA reduced if flight altitudes were lowered but further work is required. More generally, global civil aviation emits approximately 2 per cent of the global anthropogenic CO2 emissions. However, because of additional effects caused by aviation emissions and the formation of extra cirrus clouds, the total effect of aviation was estimated by the International Panel on Climate Change to be of the order 2.7 times larger than the effect of CO2 alone (uncertainty range two to four times). Impacts on the ozone layer refer to exhaust emissions of supersonic aircraft in the stratosphere; only computer-based studies of such effects continue since the cessation of commercial supersonic operations. The UK, in conjunction with EU partners, will continue to fund atmospheric research as a foundation for evidence-based policy development.