Meteorological Factors Affecting Winter Particulate Air Pollution in Ulaanbaatar from 2008 to 2016

Asian Journal of Atmospheric Environment

Sarangerel Enkhmaa¹  Minrui Wang²  Kenji Kai²  Nobuo Sugimoto³ 

[1] Government Implementing Agency for Meteorology & Environmental Monitoring, Juulchin street-5, Ulaanbaatar-15160, Mongolia;Graduate School of Environmental Studies, Nagoya University, D2-1(510) Furo-cho, Nagoya, Aichi 464-8601, Japan;National Institutes for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-0053, Japan;

关键词: lidar;    mixed layer;    radiosonde;    temperature inversion layer;    pm2.5;   

DOI  :  10.5572/ajae.2018.12.3.244

来源: DOAJ

【 摘 要 】

Ulaanbaatar, the capital of Mongolia, is subject to high levels of atmospheric pollution during winter, which severely threatens the health of the population. By analyzing surface meteorological data, ground-based LIDAR data, and radiosonde data collected from 2008 to 2016, we studied seasonal variations in particulate matter (PM) concentration, visibility, relative humidity, temperature inversion layer thickness, and temperature inversion intensity. PM concentrations started to exceed the 24-h average standard (50 μg/m3) in mid-October and peaked from December to January. Visibility showed a significant negative correlation with PM concentration. Relative humidity was within the range of 60-80% when there were high PM concentrations. Both temperature inversion layer thickness and intensity reached maxima in January and showed similar seasonal variations with respect to PM concentration. The monthly average temperature inversion intensity showed a strong positive correlation with the monthly average PM2.5 concentration. Furthermore, the temperature inversion layer thickness exceeded 500 m in midwinter and overlaid the weak mixed layer during daytime. Radiative cooling enhanced by the basin-like terrain led to a stable urban atmosphere, which strengthened particulate air pollution.

【 授权许可】

Unknown