In order to better understand the dispersion, transport and deposition of air pollutants in the typical urban environment, we have been cooperating with the Shanghai Pudong Environmental Monitoring Center to set up an air quality vertical monitoring network on the Shanghai Center Building (625 m), aiming to accurately capture the the dynamic processes involved in the vertical distribution of air pollutants.

The main problem we faced at the start of the project is the selection of monitoring equipments. Due to the various constraints such as space, safety and later maintenance needs, it has not been possible to install cabinet type standard instruments. For these reasons, we opted for miniaturized and easy-to-install instruments, but their monitoring data must be accurate.

The project has been  steadily running since November 2020, continuously and in real-time recording the vertical profiles of the typical atmospheric pollutant including PM_2.5, PM₁₀, CO, NO, NO₂, O₃, and temperature, relative humidity and atmospheric pressure at 9 different heights within 30 to 630 meters. During this process, the Cambri portable air monitors have been keeping on providing long-term, stable, reliable, and science-grade data and technical supports, by effectively capturing the three-dimensional dynamic variation trends of these atmospheric pollutants in the urban boundary layer. Through analysis of the monitoring data, we haven been able to gain deeper insights into the transport, production and dissipation mechanisms of these atmospheric pollutants, which in turn provides important technical supports in formulating air pollution forecasting and prevention policies.

Published papers can be found at:

X Hao et al., Online vertical measurement of air pollutants: Development of a monitoring platform on a skyscraper and its application in Shanghai, Atmospheric Pollution Research, 13, 101477, 2022;

YX Chen et al., Impacts of transportation emissions on horizontal and vertical distributions of air pollutants in Shanghai: insights from emission reduction in COVlD-19 lockdown, Atmospheric Environment X, 22, 100267, 2024;.

During scientific research and pratical teaching sessions, most instruments, although they may work properly in the lab, tend to show some kind of problems in the complex, volatile field environment. These include low data quality under high temperature, high relative humidity conditions or when these two parameters vary rapidly, data transmission was not real-time, calibration process is too complex/demanding, or that the instruments are heavy and therefore not portable. 　

Through comparison and trial uses of various domestic and overseas brands, we have finally chosen Cambri micro station as our outdoor monitoring device. It has since shown to cope well with the extreme environments such as the very cold, high-mountain or the hot and humid coastal ones, and have been consistently providing accurate monitoring data in projects such as "Characterizing pollution features in the ship emission affected Zhoushan atmosphere" and "Simulating traffic emissions using machine learning approaches".

Peer-reviewed publications include:

Yangzhou Wu, Dantong Liu*, Xiaotong Wang, et al., Ambient marine shipping emissions determined by vessel operation mode along the East China Sea, Science of The Total Environment, 769, 144713, 10.1016/j.scitotenv.2020.144713, 2021.

Hao Qiu, Dantong Liu*, Yangzhou Wu et al., Study of ship emission characteristics through a combined online monitoring and auto-recognition system along the coast of East China Sea, Environmental Science (in Chinese), 1-14, 10.13227/j.hjkx.202110069, 2022.