TRACER TRANSPORT FOR REALISTIC AIRCRAFT EMISSION SCENARIOS CALCULATEDUSING A 3-DIMENSIONAL MODEL

A three-dimensional transport model, which uses winds from a stratosph eric data assimilation system, is used to study the transport of super sonic aircraft exhaust in the lower stratosphere. A passive tracer is continuously injected into the transport model. The tracer source dist ribution is based on realistic scenarios for the daily emission rate o f reactive nitrogen species for all forecasted flight routes. Winds ar e from northern hemisphere winter/spring months for 1979 and 1989; the re are minimal differences between the tracer integrations for the 2 y ears. During the integration, peak tracer mixing ratios in the flight corridors are compared with the zonal mean and found to be greater by a factor of 2 or less, This implies that the zonal mean assumption use d in two dimensional models is reasonable during winter and spring. Th ere is a preference for pollutant buildup in the heavily traveled Nort h Pacific and North Atlantic flight corridors. Pollutant concentration in the corridors depends on the position of the Aleutian anticyclone and the northern hemisphere polar vortex edge.