Trends and relationship of O/sub 3/, NO/sub x/, and HC in the South Coast Air Basin of California

Journal Article · Thu Oct 01 04:00:00 EDT 1987 · J. Air Pollut. Control Assoc.; (United States)

OSTI ID:5212520

Kuntasal, G; Chang, T Y

A basin-wide air quality trend analysis for the South Coast Air Basin of California is conducted for hydrocarbons (HC), NO/sub x/, O/sub 3/ and CO using multi-station composite daily maximum-hour average ambient concentrations for the third quarter (July, August, and September) from 1968 to 1985. Emissions and air quality trends are compared for the period 1968-1984. Ambient HC and NO/sub x/ trends are somewhat different from estimated emission trends of HC and NO/sub x/, while a definite, downward trend of ambient CO is consistent with vehicular emission control measures. Basin-wide ambient HC, NO/sub x/ and O/sub 3/ appear to show downward trends for the period 1970-1985, but because of high fluctuations it is difficult to delineate trends for shorter periods. The meteorology (850 mb temperature)-adjusted O/sub 3/ shows a more consistent downward trend than does unadjusted O/sub 3/. Polynomial and multiplicative regression models for basin-wide empirical O/sub 3/-HC-NO/sub x/ relationships indicate that the O/sub 3/ variation is explained largely by the meteorological variable (850 mb temperature) although model estimates are improved by adding HC and NO/sub x/ concentration terms

• Research Organization: Ford Motor Co., Dearborn, MI (USA)
• OSTI ID: 5212520
• Journal Information: J. Air Pollut. Control Assoc.; (United States), Journal Name: J. Air Pollut. Control Assoc.; (United States) Vol. 37:10; ISSN JPCAA
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION
AIR QUALITY
CALIFORNIA
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
COMPARATIVE EVALUATIONS
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL QUALITY
FEDERAL REGION IX
HYDROCARBONS
MATHEMATICAL MODELS
METEOROLOGY
NITROGEN COMPOUNDS
NITROGEN OXIDES
NORTH AMERICA
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
OZONE
POLLUTION
USA