Evolving trend and self-similarity of ozone pollution in central Hong Kong ambient during 1984–2002

Lu, Wen-Hsiang; Wang, Xiekang

doi:10.1016/j.scitotenv.2005.03.015

Cited by 22 publications

(14 citation statements)

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“…An et al, 2007;Chan and Yao, 2008;Duan et al, 2008;Jiang et al, 2008;Zhang et al, 2008;Guo et al, 2009;Shao et al, 2009;Ma et al, 2012), and the background air pollutant concentrations have steadily increased (Chan and Yao, 2008;Zhang et al, 2008;Tang et al, 2009;Ma et al, 2012;Liu et al, 2013). Many studies on the O 3 pollution, including satellite data analyses, field experiments and model simulations, have been carried out over China in order to investigate the temporal and spatial characteristics of surface photochemical pollution (Lu and Wang, 2006; H. X. Tu et al, 2007;Zhang et al, 2007Zhang et al, , 2008Geng et al, 2008;Tang et al, 2008Tang et al, , 2009Chen et al, 2009;Han et al, 2011;Ding et al, 2013;Xie et al, 2016b), nonlinear photochemistry of O 3 and its precursors (Lam et al, 2005;Ran et al, 2009;Liu et al, 2010;Li et al, 2011;Xie et al, 2014), interactions between O 3 and aerosols (Lou et al, 2014;Shi et al, 2015), the effects of urbanization on O 3 formation Liao et al, 2015;Li et al, 2016;Xie et al, 2016a;Zhu et al, 2015) and other essential impact factors (Jiang et al, 2012;Li et al, 2012;Wei et al, 2012;…”

Section: Introductionmentioning

confidence: 99%

Integrated studies of a regional ozone pollution synthetically affected by subtropical high and typhoon system in the Yangtze River Delta region, China

et al. 2016

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Abstract. Severe high ozone (O 3 ) episodes usually have close relations to synoptic systems. A regional continuous O 3 pollution episode was detected over the Yangtze River Delta (YRD) region in China during 7-12 August 2013, in which the O 3 concentrations in more than half of the cities exceeded the national air quality standard. The maximum hourly concentration of O 3 reached 167.1 ppb. By means of the observational analysis and the numerical simulation, the characteristics and the essential impact factors of the typical regional O 3 pollution are comprehensively investigated. The observational analysis shows that the atmospheric subsidence dominated by the western Pacific subtropical high plays a crucial role in the formation of high-level O 3 . The favorable weather conditions, such as extremely high temperature, low relative humidity and weak wind speed, caused by the abnormally strong subtropical high are responsible for the trapping and the chemical production of O 3 in the boundary layer. In addition, when the YRD cities are at the front of Typhoon Utor, the periphery circulation of typhoon system can enhance the downward airflows and cause worse air quality. However, when the typhoon system weakens the subtropical high, the prevailing southeasterly surface wind leads to the mitigation of the O 3 pollution. The integrated process rate (IPR) analysis incorporated in the Community Multi-scale Air Quality (CMAQ) model is applied to further illustrate the combined influence of subtropical high and typhoon system in this O 3 episode. The results show that the vertical diffusion (VDIF) and the gas-phase chemistry (CHEM) are two major contributors to O 3 formation. During the episode, the contributions of VDIF and CHEM to O 3 maintain the high values over the YRD region. On 10-12 August, the cities close to the sea are apparently affected by the typhoon system, with the contribution of VDIF increasing to 28.45 ppb h −1 in Shanghai and 19.76 ppb h −1 in Hangzhou. In contrast, the cities far away from the sea can hardly be affected by the periphery circulation of typhoon system. When the typhoon system significantly weakens the subtropical high, the contribution values of all individual processes decrease to a low level in all YRD cities. These results provide an insight for the O 3 pollution synthetically impacted by the western Pacific subtropical high and the tropical cyclone system.

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Section: Introductionmentioning

confidence: 99%

Integrated studies of a regional ozone pollution synthetically affected by subtropical high and typhoon system in the Yangtze River Delta region, China

et al. 2016

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“…Strong winds during the monsoon season are capable of transporting ozone the long distances to the monitoring stations as is suggested by Akimoto (1996), Pochanart and Kreasuwun (2001), Lu and Wang (2006), Ishii et al (2007), Al-Jeran and Khan (2009) and Shan et al (2009). These particular seasons (May to September) and (December to March) can also be correlated to biomass burning in Southeast Asia, particularly from Sumatra, Indonesia and Indochina respectively.…”

Section: Discussionmentioning

confidence: 81%

Variation of Surface Ozone Recorded at the Eastern Coastal Region of the Malaysian Peninsula

Ismail

Latif²,

Azmi

et al. 2010

American Journal of Environmental Sciences

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Problem statement:Variations of ozone (O 3 ) concentrations in the Eastern Coastal Region of the Malaysia peninsula were investigated using data obtained from the Malaysian Department of the Environment. The aim of this study was to determine the monthly and seasonal variations of ozone concentrations at all monitoring sites. This study deals with the air quality data recorded at four air quality monitoring stations in the East Coast of the Malaysian peninsula over a ten year period (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006). Approach: We focused on the usage of S-Plus and SPSS to analyze this data. The S-Plus programming was used to impute missing data and SPSS was used to obtain the variations of ozone and also to clarify the relationship between stations. Results: Over the entire 10 year period (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006), the trend in annual baseline ozone generally increased each year for all the four monitoring sites. There was also a seasonal variability in the measured ozone levels with high concentrations during the southwest monsoon and the northeast monsoon season, producing a significant increase in the amplitude of the seasonal cycle. The results also shown that the highest ozone concentrations were recorded at the Bukit Kuang air monitoring station (S1), with a daily mean value of 19 ppb followed by the Indera Mahkota air monitoring station (S2). The concentration of ozone recorded at Kota Bharu (S3) and Kuala Terengganu (S4), two stations located in the city centre, was found to be lower than the values recorded at Bukit Kuang and Indera Mahkota. The correlation between O 3 and NO is high at Kuala Terengganu (S4) (ρ = -0.579), whilst the relationship between O 3 and NO 2 are high (ρ = -0.397) at Indera Mahkota (S2). Conclusion: The concentration of ozone in the East Coast of Malaysian peninsula depends on the concentration of NOx and seasonal meteorological factors.

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“…Interest to anisotropic self-similar random fields is motivated by applications coming from climatological and environmental sciences (see [8,9]). Several authors have proposed to apply such random fields for modelling phenomena in spatial statistics, stochastic hydrology and imaging processing (see [2,4,5]).…”

Section: Definitionmentioning

confidence: 99%

Example of a Gaussian Self-Similar Field With Stationary Rectangular Increments That Is Not a Fractional Brownian Sheet

Makogin

Mishura

2015

Stochastic Analysis and Applications

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We consider anisotropic self-similar random fields, in particular, the fractional Brownian sheet. This Gaussian field is an extension of fractional Brownian motion. We prove some properties of covariance function for self-similar fields with rectangular increments. Using Lamperti transformation we obtain properties of covariance function for the corresponding stationary fields. We present an example of a Gaussian self-similar field with stationary rectangular increments that is not a fractional Brownian sheet.

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Evolving trend and self-similarity of ozone pollution in central Hong Kong ambient during 1984–2002

Cited by 22 publications

References 13 publications

Integrated studies of a regional ozone pollution synthetically affected by subtropical high and typhoon system in the Yangtze River Delta region, China

Integrated studies of a regional ozone pollution synthetically affected by subtropical high and typhoon system in the Yangtze River Delta region, China

Variation of Surface Ozone Recorded at the Eastern Coastal Region of the Malaysian Peninsula

Example of a Gaussian Self-Similar Field With Stationary Rectangular Increments That Is Not a Fractional Brownian Sheet

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