TRENDS IN URBAN AIR QUALITY

AN EVALUATION OF TRENDS IS A MEANS TO ASSESS THE NET RESULT OF NUMEROUS INTERRELATED FACTORS THAT AFFECT THE QUALITY OF OUR AIR RESOURCES. FACTORS SUCH AS POPULATION GROWTH, INDUSTRIAL ACTIVITY, ENERGY CONSUMPTION, RURAL-URBAN DISTRIBUTION OF POPULATION, THE SHAPE AND SIZE OF METROPOLITAN AREAS, VARIOUS SOCIAL AND ECONOMIC CHANGES, AND THE EFFECTIVENESS OF EFFORTS TO CONTROL POLLUTION AT ITS SOURCE ALL PLAY AN IMPORTANT ROLE IN DETERMINING THE RESULTING AIR QUALITY. SOME OF THE CURRENT EFFECTS OF URBAN CENTERS ON AIR QUALITY ARE ANALYZED AND THE TRENDS ASSOCIATED WITH POPULATION AND GEOGRAPHICAL LOCATION. SAMPLES OF TOTAL SUSPENDED PARTICULATES COLLECTED AT VARIOUS URBAN AND NON-URBAN AREAS WERE ANALYZED FOR CERTAIN METAL AND NONMETAL SUBSTANCES THAT EXHIBIT BIOLOGICAL ACTIVITY. THESE SUBSTANCES INCLUDE SULFATES, NITRATES, FLUORIDES, BENZINE SOLUABLE ORGANICS, BENZO(4)PYRENE, COPPER, CHROMIUM, MANGANESE, NICKEL, TIN, TITANIUM, VANADIUM, LEAD, ETC. THE RELATIVE INFLUENCE OF URBAN ACTIVITY ON THE AMBIENT LEVELS OF TEN METALS IS SHOWN IN A FIGURE. RELATIVE CONCENTRATIONS OF THESE METALS IN THE ATOMSPHERE ARE QUITE DIFFERENT WITH LEAD, IRON, AND ZINC BEING THE MOST ABUNDANT. FOR ALL BUT COPPER THE URBAN LOCATIONS, INDICATING THAT URBAN ACTIVITIES PROBABLY CONTRI- BUTE SIGNIFICANTLY TO THE NONURBAN BACKGROUND LEVELS OF THESE POLLUTANTS. THERE ARE ALSO GEOGRAPHIC DIFFERENCES IN AMBIENT LEVELS OF THESE METALS. THE MANNER IN WHICH POLLUTION LEVELS DIMINISH AS DISTANCE FROM THE CORE OF AN URBAN AREA IS ILLUSTRATED IN A TABLE. ANOTHER MEASURE OF PARTICULATE POLLUTION IS SETTLEABLE DUST LOADING. UNFORTUNATELY THE SAMPLING FOR GASEOUS POLLUTANTS IS NOT AS COMPLETE AND WIDESPREAD AS THAT FOR PARTICULATE MATTER. THE ROUTINE MONITORING OF GASES IN A FASHION AMENABLE TO TREND ANALYSES WAS STARTED BY THE FEDERAL GOVERNMENT IN 1962, AND THEN IN ONLY 6 URBAN AREAS. THE ANNUAL AVERAGE CONCENTRATIONS OF SULPHUR DIOXIDE FOR THE 6 CITIES ARE SHOWN IN A FIGURE. THERE ARE INDICATIONS THAT THE LEVELS ARE DECREASING SOMEWHAT IN THE CORE AREAS OF THESE CITIES. WITH RESPECT TO OTHER GASEOUS POLLUTANTS SUCH AS CARBON MONOXIDE AND OXIDANT, LITTLE CAN BE SAID ABOUT CHANGES IN AMBIENT LEVELS. THE LACK OF SUFFICIENT AMOUNT OF DATA PREVENT THE ESTABLISHMENT OF TRENDS IN AIR QUALITY. THE UTILIZATION IS RECOMMENDED OF THE FOLLOWING TECHNIQUES: (1) PROJECTING POTENTIAL TO POLLUTE COMMENSURATE WITH EXPECTATIONS OF POPULATION GROWTH AND STANDARD OF LIVING, AND (2) THE USE OF MATHEMATICAL MODELS TO ASSIST IN THE EVALUATION OF SOURCE-RECEPTOR RELATIONSHIPS, BOTH TO INTERPRET EXISTING DATA AND TO PLAN THE NETWORK FOR COLLECTING ADDITIONAL DATA. PROJECTED TRENDS IN POWER GENERATION AND TOTAL SULPHUR DIOXIDE EMISSION TO THE ATMOSPHERE ARE SHOWN IN GRAPHS.

  • Supplemental Notes:
    • Vol 51, No 5, PP 468-475, 15 FIG, 1 TAB
  • Authors:
    • Ludwig, J H
    • Morgan, G B
    • Mcmullen, T B
  • Publication Date: 0

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Filing Info

  • Accession Number: 00229824
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 3 1970 12:00AM