274 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1956 



Angeles County, for which extensive data on the meteorological con- 

 ditions and the distribution of pollution sources are available, and 

 which is a good proving ground for atmospheric pollution studies. A 

 theoretical analysis determines the contributions of pollutants dis- 

 persed from the following five general sources: (1) Motorcars, (2) 

 oil and gas heating, (3) refuse incinerators, (4) petroleum industry, 

 and (5) other industries. The expected effects of various improve- 

 ments in the operation of incinerators, cars, and industry can then be 

 evaluated using mathematical models with appropriate characteristics 

 representing these improvements. The effect of a partial reduction in 

 the production of certain pollutants by industry is calculated. Since 

 motorcar exhausts contribute largely to the air contamination in Los 

 Angeles, the effect on the pollution pattern of such general improve- 

 ments as the reduction of exhaust gases during deceleration and idling 

 periods can also be evaluated. 



Mathematical models can then be used to determine: (1) Tempo- 

 rary emergency measures to be taken when atmospheric pollution 

 threatens to reach the allowable contamination levels, (2) efficacy of 

 various plans to reduce the pollution in an urban area, (3) effects of 

 a new pollution source on the mean concentration patterns, (4) pollu- 

 tion patterns for a city after future expansions, and (5) efficacy of 

 various solutions in urban planning on predicted contamination levels. 

 In the present paper we are discussing some estimates of probable 

 pollution patterns which would follow industrial expansions and pop- 

 ulation increases of an urban area. Possible effects of increasing the 

 combustion efficiency and other industrial operations, as well as the 

 improvement of traffic, on present and future pollution patterns are 

 then examined. Such an analysis may have some interest to urban 

 planning which should be of particular importance in connection with 

 the forthcoming development of nuclear industry. 



It should be emphasized that a large part of the results presented 

 in this paper refers to a mathematical model representing the atmos- 

 pheric pollution problems in Los Angeles County. Such a model is 

 necessarily a simplification of the real physical phenomena taking 

 place in the atmosphere. Although most of the data on the relative 

 contributions of each pollution source are based on published reports 

 in which these contributions are estimated, the mathematical model 

 cannot reproduce exactly the real situation. 



ATMOSPHERIC POLLUTION CONTROL 



Production, emission, transfer, contact, and damage — this is the 

 story of atmospheric pollution. At each of these stages the reduction 

 of the danger of contamination can be attempted, and in most cases 

 scientific and technological methods for this purpose already exist [3]. 



