DOI: 10.1016/j.atmosenv.2017.10.039
Scopus记录号: 2-s2.0-85033406831
论文题名: Observation-based trends in ambient ozone in the Czech Republic over the past two decades
作者: Hůnová I ; , Bäumelt V
刊名: Atmospheric Environment
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2018
卷: 172 起始页码: 157
结束页码: 167
语种: 英语
英文关键词: Ground-level ozone
; NOx
; Time trends
Scopus关键词: Landforms
; Nitrogen oxides
; Ozone
; Rural areas
; Ambient ozone concentration
; Geographical patterns
; Ground-level ozone
; High quality data
; Long term monitoring
; Mean concentrations
; Peak concentrations
; Time trends
; Urban growth
; ozone
; ambient air
; atmospheric chemistry
; concentration (composition)
; decadal variation
; emission
; environmental monitoring
; mountain region
; nitrogen oxides
; observational method
; ozone
; trend analysis
; air monitoring
; air pollutant
; air pollution
; air temperature
; ambient air
; Article
; climate change
; concentration ratio
; Czech Republic
; electric power plant
; exhaust gas
; highway
; priority journal
; rural area
; solar radiation
; summer
; urban area
; Ceske Budejovice
; Czech Republic
; Jihocesky
; Snieznik Mountains
; Sudetes
Scopus学科分类: Environmental Science: Water Science and Technology
; Earth and Planetary Sciences: Earth-Surface Processes
; Environmental Science: Environmental Chemistry
英文摘要: We present the trends in ambient ozone concentrations based on high quality data measured continuously at 26 long-term monitoring sites (9 urban, 17 rural including 10 mountain stations) in the Czech Republic in 1994–2015. We considered annual and summer medians, the 10th and 98th percentiles, maximum daily 8-h running mean concentrations and exposure index AOT40F. For all indicators taken into account except for the 10th percentile, our results showed a similar pattern with significant decreasing trends for about one half of the examined sites. We obtained similar results for all types of sites. The most pronounced decrease in O3 concentrations was recorded at mountain sites. Namely, at the Šerlich mountain site, with an overall decrease per year in annual median by 0.43 ppb, summer median by 1.17 ppb, maximal daily 8-h average by 0.45 ppb, the 10th percentile by 0.62 ppb. The peak concentrations indicated by the 98th percentile and AOT40F decreased most at urban site České Budějovice by 0.75 ppb and 0.84 ppb h per year, respectively. For sites exhibiting significant decreasing trends, an overall decrease per year in annual median was 0.22 ppb, in summer median 0.41 ppb, in the 10th percentile 0.23 ppb, in the 98th percentile 0.53 ppb, and in AOT40F 0.51 ppb h. A significant increasing trend was detected only in the 10th percentile at just three sites, with the highest increase of 0.19 ppb per year recorded at the rural site Sněžník. Moreover, a consistent decrease in limit value exceedances was detected, with by far the highest violation recorded in the meteorologically exceptional year of 2003. Out of the 26 sites under review, seven have not recorded a significant decreasing trend in O3 in any of the considered statistics. The lack of trends in O3 at these seven sites is likely associated with changing time patterns in local NO and NO2 emissions: in particular, with the increasing ratio in NO2/NOx. There is an obvious geographical pattern in recorded O3 trends: most of the sites with no trend detected are situated in the North-western region of the CR with numerous energy-producing large emission sources, partly denitrified recently. Our results clearly indicated that, for O3 decrease, the ratio between individual NO and NO2 forms is critical, and that a simultaneous significant decrease in both NO and NO2 concentrations is not a sufficient prerequisite. Apart from changes in car fleet in urban areas or near motorways, this factor might be of particular relevance in formerly highly polluted areas, where emissions from large power plants recently substantially decreased. © 2017 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83138
Appears in Collections: 气候变化事实与影响
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作者单位: Czech Hydrometeorological Institute, Czech Republic
Recommended Citation:
Hůnová I,, Bäumelt V. Observation-based trends in ambient ozone in the Czech Republic over the past two decades[J]. Atmospheric Environment,2018-01-01,172