We carried out field measurements of aerosols in Lhasa, a major city in the Tibetan Plateau that has been experiencing fast urbanization and industrialization. Aerosol number size distribution was continuously measured using an optical particle size spectrometer near the center of Lhasa city during the Asian summer monsoon season in 2016. The mass concentration of fine particles was modulated by boundary layer dynamics, with an average of 11 μg m⁻³ and the high values exceeding 50 μg m⁻³ during religious holidays. Daytime high concentration coincided with the religious burning of biomass and incense in the temples during morning hours, which produced heavy smoke. Factor analysis revealed a factor that likely represented religious burning. The factor contributed 34% of the campaign-average fine particle mass and the contribution reached up to 80% during religious holidays. The mass size distribution of aerosols produced from religious burnings peaked at ∼500 nm, indicating that these particles could efficiently decrease visibility and promote health risk. Because of its significance, our results suggest that further studies of religious burning, a currently under-studied source, are needed in the Tibetan Plateau and in other regions of the world where religious burnings are frequently practiced.

我们在拉萨市进行了气溶胶的现场测量，拉萨是青藏高原的一个主要城市，一直在经历着快速的城市化和工业化。在2016年亚洲夏季风季节期间，使用光学粒径谱仪连续测量了拉萨市中心附近的气溶胶数大小分布。通过边界层动力学调节细颗粒的质量浓度，平均浓度为11μgm ^-3且高值超过50μgm ^-3在宗教节日期间。白天的高浓度恰逢宗教信仰在清晨燃烧太阳穴中的生物质和香气，从而产生浓烟。因素分析揭示了一个可能代表宗教燃烧的因素。该因素贡献了竞选平均微粒质量的34％，在宗教节日期间，这一贡献达到了80％。宗教燃烧产生的气溶胶的质量分布在约500 nm达到峰值，表明这些颗粒可以有效地降低能见度并增加健康风险。由于其重要性，我们的结果表明，在青藏高原和世界上经常发生宗教焚烧活动的其他地区，需要对宗教焚烧进行进一步的研究，而目前仍未充分研究这一问题。