It has been known since the 1960s that the emission of nitrous oxides and water vapor in the engine exhaust from supersonic transport planes may be destructive to the ozone layer, the layer which keeps much of the sun=s biologically harmful ultraviolet radiation from reaching the Earth=s surface (5). This paper will look at the data which has emerged over the years since then in respect to the effects of aircraft emissions on stratospheric ozone.
In 1995, the Nobel prize in chemistry was awarded to three atmospheric chemists for their research which identified chemicals that destroy stratospheric ozone (5). The discovery paved the way for an international agreement to ban the production of ozone-destroying compounds known as chlorofluorocarbons, beginning on January 1, 1996. Paul Crutzen discovered that a naturally produced compound, nitrous oxide, spawns related chemicals in the atmosphere which destroy individual ozone molecules. F. Sherwood Rowland and Mario Molina demonstrated that industrially produced chlorofluorocarbons also drift up to the stratosphere, where they give rise to ozone-destroying reactions.
In 1971, Crutzen=s theory was used to block the plan for the development of a fleet of high-speed supersonic aircraft (SSTs). It was believed that the nitrogen oxides in the exhaust from these planes would pose a serious threat to the ozone layer. As a result, the U. S. SST plan was abandoned. It is paradoxical that, while the environmental consequences of increasing the number of high-speed aircraft are viewed as being a serious threat to the ozone layer, air travel continues to increase annually (7). The demand for faster aircraft for travel to more distant destinations is spurring atmospheric chemists to research the effects of emissions from SSTs, and to develop ways to make engines whose exhaust is less damaging to the ozone layer.
Emissions from aircraft include many species that play a role in atmosp...