Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China.
Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China.
Sci Total Environ. 2022 Jul 20;831:154788. doi: 10.1016/j.scitotenv.2022.154788. Epub 2022 Mar 25.
Ozone (O) pollution has been a persistent problem in Hong Kong, particularly in autumn when severe O pollution events are often observed. In this study, linear regression analyses of long-term O data in suburban Hong Kong revealed that the variation of autumn O obviously leveled off during 2005-2017, mainly due to the significant decrease of autumn O in 2013-2017 (period II), despite the increase in 2005-2012 (period I). In addition, the rise of O in summer and winter also ceased since 2013. In contrary, O continuously increased throughout the spring of 2005-2017, especially in period II. Consequently, an incessant increase of overall O was observed during 2005-2017. A statistical model combining Kolmogorov-Zurbenko filter with multiple linear regressions, and a photochemical box model incorporating CB05 mechanism were applied to probe the causes of the above trends. In general, O production was controlled by VOC-limited regime throughout 13 years. The meteorological variability and regional transport facilitated the O growth in period Ι. In contrast, the unchanged O level in period II was attributable to the negative impact of meteorological variability and reduction of regional transport effect on O formation and accumulation, as well as the negligible change in locally-produced O. In autumn of period II, the inhibitory meteorological variability, reduced regional transport, and alleviated local production were the driving force for the hard-earned decrease of O. However, the remarkable rise of spring O was caused by the reduction of NO, especially in the spring of period II. The findings of the long-term and seasonal variations of O pollution in Hong Kong are helpful for future O mitigation.
臭氧（O）污染一直是香港的一个长期存在的问题，特别是在秋季，经常会出现严重的臭氧污染事件。在这项研究中，对香港郊区的长期臭氧数据进行线性回归分析表明，2005 年至 2017 年期间，秋季臭氧的变化明显趋于平稳，主要是由于 2013 年至 2017 年（第二期）秋季臭氧显著下降，尽管 2005 年至 2012 年（第一期）有所增加。此外，夏季和冬季的臭氧上升也自 2013 年以来停止。相反，2005 年至 2017 年整个春季的臭氧持续增加，特别是在第二期。因此，2005 年至 2017 年期间观察到臭氧总量持续增加。应用结合了柯尔莫哥洛夫-祖尔贝诺滤波和多元线性回归的统计模型，以及包含 CB05 机制的光化学箱模型，探究了上述趋势的原因。总的来说，13 年来，臭氧的产生一直受到 VOC 限制。气象变化和区域传输促进了第一期的臭氧增长。相反，第二期臭氧水平不变是由于气象变化的负面影响以及区域传输对臭氧形成和积累的影响减少，以及本地产生的臭氧变化可以忽略不计。在第二期的秋季，抑制性气象变化、减少的区域传输和缓解的本地生产是臭氧来之不易的下降的驱动力。然而，春季臭氧的显著上升是由于 NO 的减少，特别是在第二期的春季。香港臭氧污染的长期和季节性变化的研究结果有助于未来的臭氧减排。
