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Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer
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Remarkable spring increase overwhelmed hard-earned autumn decrease in ozone pollution from 2005 to 2017 at a suburban
Yangzong Zeren1, Hai Guo1, Xiaopu Lyu1
1Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China.
The Science of the Total Environment
|March 28, 2022
Summary
Hong Kong
Area of Science:
- Atmospheric Chemistry
- Environmental Science
- Air Pollution Studies
Background:
- Ozone (O3) pollution is a significant environmental issue in Hong Kong.
- Severe ozone pollution events are frequently observed, especially during autumn.
Purpose of the Study:
- To analyze long-term ozone (O3) trends in Hong Kong from 2005-2017.
- To investigate the underlying causes of observed seasonal and overall O3 variations.
- To understand the impact of meteorological factors, regional transport, and local emissions on O3 levels.
Main Methods:
- Linear regression analysis of long-term O3 data.
- Statistical modeling using Kolmogorov-Zurbenko filter and multiple linear regressions.
- Photochemical box modeling with the CB05 mechanism.
Main Results:
- Autumn O3 leveled off from 2013-2017 due to decreased O3, despite earlier increases.
- Summer and winter O3 rise ceased after 2013, while spring O3 continuously increased.
- Overall O3 showed an increasing trend from 2005-2017, influenced by VOC-limited conditions.
- Reduced NOx emissions significantly contributed to the rise in spring O3.
Conclusions:
- Ozone pollution dynamics in Hong Kong are complex, with varying seasonal trends.
- Meteorological variability and regional transport play crucial roles in O3 formation and accumulation.
- Reduced NOx emissions can lead to increased spring O3, highlighting the need for targeted mitigation strategies.
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