Wu Jiarui, Bei Naifang, Wang Yuan, Su Xiaoli, Zhang Ningning, Wang Lili, Hu Bo, Wang Qiyuan, Jiang Qian, Zhang Chenchong, Liu Yangfan, Wang Ruonan, Li Xia, Lu Yuxuan, Liu Zirui, Cao Junji, Tie Xuexi, Li Guohui, Seinfeld John
State Key Laboratory of Loess Science, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
Proc Natl Acad Sci U S A. 2025 Jan 7;122(1):e2402281121. doi: 10.1073/pnas.2402281121. Epub 2024 Dec 23.
Aerosol light absorption has been widely considered as a contributing factor to the worsening of particulate pollution in large urban areas, primarily through its role in stabilizing the planetary boundary layer (PBL). Here, we report that absorption-dominated aerosol-radiation interaction can decrease near-surface fine particulate matter concentrations ([PM]) at a large-scale during wintertime haze events. A "warm bubble" effect by the significant heating rate of absorbing aerosols above the PBL top generates a secondary circulation, enhancing the upward motion (downward motion) and the convergence (divergence) in polluted (relatively clean) areas, with a net effect of lowering near-surface [PM]. Furthermore, aerosol absorption of ultraviolet-wave light effectively reduces the photolysis of chemical species, i.e., aerosol-photolysis interaction, hindering ozone formation, reducing atmospheric oxidizing capability, and suppressing secondary aerosol concentrations. Our model assessment reveals that the synergetic two effects decrease near-surface [PM] by around 7.4%, so the presence of light-absorbing aerosols can considerably alleviate particulate pollution during wintertime haze events. Such negative feedbacks to the aerosol loading should be considered in weather/climate prediction and health assessment models.
气溶胶光吸收一直被广泛认为是导致大城市地区颗粒物污染恶化的一个因素，主要是通过其在稳定行星边界层（PBL）中的作用。在此，我们报告，在冬季雾霾事件期间，以吸收为主的气溶胶 - 辐射相互作用能够在大尺度上降低近地表细颗粒物浓度（[PM]）。PBL顶部上方吸收性气溶胶的显著加热率产生的“暖泡”效应会引发二次环流，增强污染（相对清洁）区域的上升运动（下降运动）和辐合（辐散），其净效应是降低近地表[PM]。此外，气溶胶对紫外光的吸收有效地减少了化学物种的光解，即气溶胶 - 光解相互作用，阻碍了臭氧形成，降低了大气氧化能力，并抑制了二次气溶胶浓度。我们的模型评估表明，这两种协同效应使近地表[PM]降低了约7.4%，因此吸光气溶胶的存在能够在冬季雾霾事件期间显著缓解颗粒物污染。在天气/气候预测和健康评估模型中应考虑这种对气溶胶负荷的负反馈。
