Trends and variability of ground-level O3 in Connecticut over the period 1981-1997.
The temporal and spatial characteristics of ground-level (tropospheric) O3 measured at 10 monitoring stations in Connecticut were studied from 1981 to 1997. To detect the O3 trend caused by changes in precursor emissions, moving average filters and a linear least-squared regression model were used to eliminate the short-term variation and effects of temperature from raw time-series O3 data. The results showed a significant decrease in the number of days exceeding the National Ambient Air Quality Standards (NAAQS) and a small change in total O3 concentration. The analysis indicated that the variation of daily maximum O3, caused by changes in emissions, explained more than 10% of the total O3 variation in Bridgeport and East Hartford during the past 17 years. Meanwhile, a strong weekly cycle was also found in O3 time-series data, resulting in lower O3 concentration in urban areas than in nonurban areas, implying that land use and land cover have impacts on the spatial distribution of ground-level O3 in Connecticut.
Yang
Jiansheng
J
Department of Natural Resources Science, University of Rhode Island, Coastal Institute, Kingston, Rhode Island 02881, USA.
Miller
David R
DR
D000393:Air Pollutants / Q000032:analysis*; D002947:Cities; D003237:Connecticut; D004777:Environment; D004784:Environmental Monitoring; D010083:Oxidants, Photochemical / Q000032:analysis*; D010126:Ozone / Q000032:analysis*
D000393:Air Pollutants; D010083:Oxidants, Photochemical; D010126:Ozone