Niu Yuan, Cheng Shui-Yuan, Ou Sheng-Ju, Yao Shi-Yin, Shen Ze-Ya, Guan Pan-Bo
Key Laboratory of Beijing on Regional Air Pollution Control, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.
Huan Jing Ke Xue. 2021 Jun 8;42(6):2691-2698. doi: 10.13227/j.hjkx.202010243.
Ozone pollution in Handan has become severe in recent years and in the summer of 2018, the average maximum daily 8-hour average ozone concentration in Handan was 175 μg·m with a maximum of 257 μg·m. Ozone concentrations exceeded the National Air Quality Grade Ⅱ Standard in 59% of cases. In this study, the HO/HNO indicator was applied to analyze summertime ozone sensitivity in Handan using the WRF-CMAQ modeling system. The results showed that HO/HNO was more appropriate than other ozone indicators, both theoretically and based on simulation outputs. The good simulation effect of CMAQ on HO and HNO was attributed to fine emission inventory and grid resolution. The HO/HNO simulation results showed that the relative importance of a VOCs-limited regime decreased month by month; a VOCs-NO-mixed-limited regime was dominant in June; and a NO-limited regime was more dominant in July and August than in June. The remarkable spatial difference in VOCs and NO emission ratios among the counties of Handan led to differences in ozone sensitivity. The VOCs-limited regime was concentrated in counties where VOCs/NO emission ratios were lower than 1.7. Southern counties had a NO-limited regime, where VOCs/NO emission ratios were higher than 6.9. Counties with VOCs/NO emission ratios varying from 1.7 to 6.9 were more susceptible to both VOCs and NO. According to these results, the transition range of HCHO/NO, O/HNO, and O/NO ratios were adjusted to 0.35-0.6, 20-35, and 10-25 respectively. Adjusting the transition range of HO/(O+NO) was not effective, indicating that this indicator may not be applicable to Handan.
近年来，邯郸的臭氧污染日益严重。2018年夏季，邯郸日最大8小时平均臭氧浓度均值为175μg·m，最高值达257μg·m。臭氧浓度超标天数占比达59%。本研究利用WRF-CMAQ模型系统，采用HO/HNO指标分析邯郸夏季臭氧敏感性。结果表明，HO/HNO指标在理论和模拟输出方面均比其他臭氧指标更具优势。CMAQ对HO和HNO的良好模拟效果得益于精细的排放清单和网格分辨率。HO/HNO模拟结果显示，VOCs限制型状态的相对重要性逐月降低；6月以VOCs-NO混合限制型状态为主；7月和8月NO限制型状态比6月更为显著。邯郸各县市VOCs与NO排放比的显著空间差异导致臭氧敏感性不同。VOCs限制型状态集中在VOCs/NO排放比低于1.7的县；南部各县为NO限制型状态，VOCs/NO排放比高于6.9；VOCs/NO排放比在1.7至6.9之间的县对VOCs和NO均更为敏感。根据这些结果，将HCHO/NO、O/HNO和O/NO比值的转变范围分别调整为0.35 - 0.6、20 - 35和10 - 25。调整HO/(O+NO)的转变范围无效，表明该指标可能不适用于邯郸地区。
