Assessing recent surface ozone concentrations in the U.K.

Bower, J.S.; Stevenson, Ken; Broughton, G.F.J.; Lampert, J.E.; Sweeney, B P; Wilken, J

doi:10.1016/1352-2310(94)90027-2

Cited by 17 publications

(11 citation statements)

References 2 publications

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“…The reaction of more ozone with vehicular NO results in lower ozone levels at A1 than at the other sites, while lower combined NO x emissions cause higher ozone levels at the A6 site. This inverse spatial relationship between ozone and NO x levels is consistent with the findings of other groups (Bower et al, 1994;Mckendry, 1993;Wu and Chan, 2000;Chou et al, 2006). Siteto-site variability is clearly closely related to site characteristics.…”

Section: Resultssupporting

confidence: 80%

Surface ozone trend details and interpretations in Beijing, 2001–2006

et al. 2009

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Abstract.Beijing is a megacity situated in the rapidly developing Beijing-Tianjin-Hebei region of northern China. In this study, we analyze data on ozone and nitrogen oxide levels obtained at six urban sites in Beijing between the months of July and September. Our goal is to investigate average trends and interpretations over the 2001-2006 period. Average concentrations of NO x (NO x =NO+NO 2 ), O 3 , and O x (O x =O 3 +NO 2 ) were 49.2±5.9 ppbv, 26.6±2.8 ppbv, and 60.3±1.9 ppbv, respectively. NO x concentrations decreased linearly at a rate of 3.9±0.5 ppbv/yr after 2002, while ozone concentrations increased at a rate of 1.1±0.5 ppbv/yr during 2001-2006, and O x concentrations remained nearly constant. The reduction of NO x emissions and elevated non-methane hydrocarbon (NMHCs) emissions may have contributed to the increased O 3 concentrations in Beijing. When the contributions from Beijing's urban and surrounding areas were disaggregated via trajectory cluster analysis, daily maximum and average O x concentrations attributable to Beijing's local emissions increased linearly at rates of 1.3±0.6 ppbv/yr and 0.8±0.6 ppbv/yr, while the O x concentrations attributable to regional areas decreased linearly at rates of 0.6±0.3 ppbv/yr and 0.5±0.3 ppbv/yr, respectively. The decrease in O x concentrations of the surrounding areas was found to counteract increasing Beijing urban O x production, leading to nearly constant O x concentrations in the Beijing region over the study period. Our results may be helpful for redefining government strategies to control the photochemical formation of air pollutants in the Beijing region. Our conclusions have relevance for developing megacities worldwide.

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Section: Resultssupporting

confidence: 80%

Surface ozone trend details and interpretations in Beijing, 2001–2006

et al. 2009

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“…The change in the overall annual mean was only statistically significant for Pusan, Taegu, and Ulsan. The long-term increasing trend in these three cities is consistent with results from rural areas in the United Kingdom, 12 north Kanto, and the areas of Kyoto and Nara in Japan. 13 In contrast, a long-term downward trend was indicated in Central London, 12 in the Tokyo bay area in Kanto, and in the Osaka bay area in Japan.…”

Section: Resultssupporting

confidence: 74%

“…The long-term increasing trend in these three cities is consistent with results from rural areas in the United Kingdom, 12 north Kanto, and the areas of Kyoto and Nara in Japan. 13 In contrast, a long-term downward trend was indicated in Central London, 12 in the Tokyo bay area in Kanto, and in the Osaka bay area in Japan. 13 However, Lefohn and Shadwick 14 found no indication of trends, either increasing or downward, at rural sites located in the United States.…”

Section: Resultssupporting

confidence: 74%

Characteristics of Urban Ground-Level Ozone in Korea

Nam

1999

Journal of the Air & Waste Management Association

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This study considers the characteristics of ground-level ozone (O 3 ) in five Korean cities over a time period of 6-8 years. The focus of this study is daily maximum 1-hr and 8-hr concentrations. For all the study cities in the period examined, the mean and most of the percentiles (5, 10, 25, 50, 75, 90, and 95) for the daily maximum 1-hr and 8-hr concentrations showed increasing trends, although not all trends were statistically significant. The daily maximum 1-hr and 8-hr concentrations slowly increased during late winter, and peaks were attained during the summer season (from May to September). All the selected cities exhibited a high degree of correlation between their daily maximum 8-hr and 1-hr concentrations. The daily maximum 8-hr concentrations, which were climatologically equivalent to the Korean 1 hr/100 parts per billion (ppb) standard, were higher than the current 8 hr/60 ppb by a difference of 8-16 ppb. Compared with other cities in Korea, Seoul recorded a substantially higher frequency of days and hours with concentrations above 1 hr/100 ppb, and a higher frequency of days with concentrations above 8 hr/60 ppb and 8 hr/80 ppb. Seoul also recorded a substantially higher frequency of hours with concentrations above 1 hr/100 ppb than days with concentrations above 1 hr/100 ppb, implying that on some days severe exceedances persisted for more than one hour per day. During multiple-day episodes a North Pacific High dominated Korea, which is quite typical in Korea during the summer season.

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“…Thus, increases in surface O 3 are associated with the reductions in ambient concentrations of NO x and NMHC. These results are similar to those obtained in Toronto and Montreal in Canada, 15 Stevenage and central London in the United Kingdom, 16 Ulsar in Korea, 17 and three sites in Baton Rouge, LA (on July 24 and September 13, 1997), 18 which all exhibited an increase in O 3 with decreasing NO x or NMHC concentrations.…”

Section: Trends In O 3 Concentrations Annual Trends In Daily Maximum supporting

confidence: 77%

“…For example, the O 3 trends in Montreal, 15 Stevenage, and Sibton 16 were not statistically significant at the 95% confidence level, but sites in Toronto 15 showed small but statistically significant upward O 3 trends. O 3 trends in most cities in Korea 17 and mid-latitude areas 19 were not statistically significant at the 90 or 95% level.…”

Section: Long-term Trends In the Annualmentioning

confidence: 99%

Trends in Concentration of Ground-Level Ozone and Meteorological Conditions during High Ozone Episodes in the Kao-Ping Airshed, Taiwan

Chen

Lai

et al. 2004

Journal of the Air & Waste Management Association

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This work analyzes the variations in daily maximum 1-hr ozone (O 3 ) concentrations and the long-term trends in annual means of hourly ambient concentrations of O 3 , nitrogen oxides (nitrous oxide ϩ nitrogen dioxide), and nonmethane hydrocarbons in the three administrative regions of Kao-Ping airshed in southern Taiwan over a recent 8-yr period. The annual or monthly means of all maxima, most 95th percentiles, and some 90th percentiles of the daily maximum 1-hr O 3 concentrations exceed the daily limit of 120 parts per billion by volume in all three regions, namely, Kao-hsiung City, Kso-hsiung County, and P'ing-tung County. The monthly means of daily maximum 1-hr O 3 concentrations exhibit distinct seasonal variations, with a bimodal form with the maxima in autumn and late winter to the middle of spring and a minimum in summer. The long-term variations in the annual means of hourly O 3 concentrations in the three regions exhibit increasing trends. These increases in O 3 are associated with the decline in ambient concentrations of nitrogen oxides and nonmethane hydrocarbons. High O 3 episodes occur most often in autumn and most rarely in summer. The seasonal mean mixing heights in descending order follow the order of spring, summer, autumn, and winter. Meteorological parameters in autumn and winter indicate that the ground-level O 3 tends to accumulate and trigger a high O 3 episode on a warm day with sufficient sunlight and low wind in a high-pressure system, consistent with the low mixing heights in these two seasons.

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Assessing recent surface ozone concentrations in the U.K.

Cited by 17 publications

References 2 publications

Surface ozone trend details and interpretations in Beijing, 2001–2006

Surface ozone trend details and interpretations in Beijing, 2001–2006

Characteristics of Urban Ground-Level Ozone in Korea

Trends in Concentration of Ground-Level Ozone and Meteorological Conditions during High Ozone Episodes in the Kao-Ping Airshed, Taiwan

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