A temperature inversion-induced air pollution process as analyzed from Mie LiDAR data.

Area of Science:

• Atmospheric Science
• Environmental Science
• Air Quality Research

Background:

• Severe air pollution events pose significant risks to public health and the environment.
• Understanding the meteorological drivers of air pollution is crucial for effective mitigation strategies.

Purpose of the Study:

• To analyze the causes and characteristics of a severe air pollution event in Nanjing, China.
• To investigate the role of meteorological conditions, specifically advection inversion, in exacerbating air pollution.

Main Methods:

• Mie scattering LiDAR data was used to retrieve aerosol extinction coefficient and aerosol optical depth (AOT).
• In situ measurements of particulate concentrations near the Earth's surface were conducted.
• Meteorological data, including temperature, humidity, wind, and barometric pressure, were analyzed using the Weather Research Forecast (WRF) model.

Main Results:

• Advection inversion was identified as the primary cause of the pollution event, occurring from 9:00 AM to 10:00 PM on December 24, 2012.
• The temperature inversion inhibited the dispersion of near-surface particulates, leading to increased atmospheric extinction coefficient.
• Aerosol optical depth (AOT) below 0.8 km rose to 0.31 during the event, while near-surface particulate concentrations remained stable around 0.2 mg/m³.

Conclusions:

• Advection inversion is a significant factor in the development of severe air pollution events in urban areas.
• Effective air pollution management requires consideration of meteorological conditions and their impact on particulate dispersion.
• Further research into the long-term effects of such pollution events is warranted.