Qin Momei, She Yongliang, Wang Ming, Wang Hongli, Chang Yunhua, Tan Zhaofeng, An Jingyu, Huang Jian, Yuan Zibing, Lu Jun, Wang Qian, Liu Cong, Liu Zhenxin, Xie Xiaodong, Li Jingyi, Liao Hong, Pye Havala O T, Huang Cheng, Guo Song, Hu Min, Zhang Yuanhang, Jacob Daniel J, Hu Jianlin
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, Nanjing University of Information Science and Technology, Nanjing, China.
State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai, China.
Nat Geosci. 2025 Jan 2;18(1):50-56. doi: 10.1038/s41561-024-01608-w.
Urban ozone (O) pollution correlates with temperature, and higher O often occurs during heat waves, threatening public health. However, limited data on how anthropogenic volatile organic compound (AVOC) precursor emissions vary with temperature hinders understanding their impact on O. Here, we show that the increase in non-combustion AVOC emissions (e.g., from volatile chemical products) during a heat wave in Shanghai contributes significantly to increased O, based on ambient measurements, emission testing, and air quality modelling. AVOC concentrations increase ~2× when the temperature increases from 25 °C to 35 °C due to air stagnation and increased emissions. During the heat wave, higher concentrations result in an 82% increase in VOC OH reactivity. Air quality simulations reveal that temperature-driven AVOC emission increases account for 8% (1.6 s) of this reactivity increase and enhance O by 4.6 ppb. Moreover, we predict a more profound (2×) increase in OH reactivity of oxygenated VOCs, facilitating radical production and O formation. Enhanced AVOC emissions trigger O enhancements in large cities in East China during the heat wave, and similar effects may also happen in other AVOC-sensitive megacities globally. Reducing AVOC emissions, particularly non-combustion sources, which are currently less understood and regulated, could mitigate potential O pollution in urban environments during heat waves.
城市臭氧（O）污染与温度相关，高温期间往往会出现较高的臭氧水平，威胁公众健康。然而，关于人为挥发性有机化合物（AVOC）前体排放如何随温度变化的数据有限，这阻碍了人们了解其对臭氧的影响。在此，基于环境监测、排放测试和空气质量模型，我们发现上海热浪期间非燃烧性AVOC排放（如来自挥发性化学产品）的增加对臭氧增加有显著贡献。由于空气停滞和排放增加，当温度从25°C升至35°C时，AVOC浓度增加约2倍。在热浪期间，较高的浓度导致挥发性有机物与羟基自由基（VOC OH）反应活性增加82%。空气质量模拟显示，温度驱动的AVOC排放增加占这种反应活性增加的8%（1.6秒），并使臭氧浓度增加4.6 ppb。此外，我们预测含氧挥发性有机物（OVOC）的OH反应活性将有更显著（2倍）的增加，促进自由基生成和臭氧形成。热浪期间，AVOC排放增加引发中国东部大城市臭氧浓度升高，全球其他对AVOC敏感的特大城市也可能出现类似影响。减少AVOC排放，尤其是目前了解较少且监管不足的非燃烧源排放，可减轻热浪期间城市环境中潜在的臭氧污染。
