The Use of a Regional-Scale Numerical Model in Addressing Certain Key Air Quality Issues Anticipated in the 1980s

Abstract

Ever since air pollution is considered as a serious matter for public concern, emphasis has almost always been on problems occurred in the immediate vicinity of the emission sources. In the early 1970s, concern over carbon monoxide, as a consequence of vehicular emissions, is primarily limited to locations in the proximity of major roadways. Sulfur dioxide or particulate problems related to the operation of industrial point sources are also restricted to an area immediately downwind of the mission stacks. Even the concern over the photochemical smog, as a result of the mixing and reaction of reactive hydrocarbons and oxides of nitrogen, has been confined in the past to the urban area where the emission sources are located. However, over the last few years, there has been a marked shift in the emphasis of air pollution problems. Instead of the typically short or episodic problems of a local nature, significant interest has been placed recently on the degradation of air quality or related problems on regional scales caused by the transpo0rt of a variety of air pollutants from a large agglomerate of sources over long distances. Listed in Table 1 are the general characteristics of the local versus regional air pollution problems. Of particular importance is the fact that the latter can often influence regions that are larger in size than many states or even countries.