Nitrogen emissions from aircraft

A large majority of air polluting emissions comes from mobile sources. The automobile is an obvious example, but other vehicles, such as semi-trucks, trains, and aircraft also contribute. Emissions from mobile sources include CO2, volatile organic compounds (VOCs), NO, and particulates. The latter may also have heavy metals, such as lead or mercury, or hazardous organics attached. Stationary sources typically burn or produce fossil fuels - coal, gasolines, and natural gas. These produce gaseous sulfur compounds (H2S, SO2, etc.), nitrogen oxides (NOJ, CO2, and particulates. Fuel producers and distributors also typically produce VOCs. 

Studies on stratospheric chemistry in the early 1970s suggested that direct emissions of nitrogen oxides from supersonic aircraft would result in a significant decline in stratospheric O3. Partly as a result of this concern, only a small fieet of supersonic aircraft was built. 

In the late 1960s, University of California physical chemist Harold S. Johnston (1920-) and Dutch atmospheric chemist Paul J. Crutzen (1933-) independently proposed that emissions of nitrogen oxides from supersonic transport aircraft (SST) flying through the stratosphere would harm the stratosphere s protective layer of ozone. 

The research of Paul J. Crutzen has been mainly concerned with the role of chemistry in climate and biogeochemistry, and in particular the photochemistry of ozone in the stratosphere and troposphere. In 1970 he hypothesized that natural ozone production by the action of solar ultraviolet radiation on molecular oxygen (O2) is mainly balanced by destraction processes, involving NO and NO2 as catalysts. These catalysts in turn result from the oxidation of N2O, a product of microbiological nitrogen conversion in soils and waters. He and Prof. Harold Johnston of the University of California, Berkeley, pointed out that NO emissions from large fleets of supersonic aircraft could cause substantial ozone losses in the stratosphere. 

There has been sustained interest in engine emissions ever since commercial turbojet traffic increased substantially in the 1970s. Ground level Ozone, acid rain and climate change can be related to pollutants from aircraft engines such as nitrogen oxides, hydrocarbons and fine particulate matter. Furthermore, air travel. 

Abstract. The impact of future aircraft emissions on concentrations of reactive nitrogen, water vapour and ozone has been calculated using the 3-dimensional stratospheric chemical transport model SCTM-1. Emissions of NOx (N0+N02) and H20 from both sub- and supersonic aircraft have been considered. 

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