19 Feb 2024
 | 19 Feb 2024

Spatiotemporal Source Apportionment of Ozone Pollution over the Greater Bay Area

Yiang Chen, Xingcheng Lu, and Jimmy C. H. Fung

Abstract. It has been found that ozone (O3) pollution episodic case is prone to appear when the Greater Bay Area (GBA) is under the control of typhoons and sub-tropical high-pressure systems in summer. To prevent these pollutions effectively and efficiently, it’s essential to understand the contribution of O3 precursors emitted from different periods and areas under these unfavorable weather conditions. In this study, we further extended the Ozone Source Apportionment Technology (OSAT) from the Comprehensive Air Quality Model with Extensions (CAMx) model to include the function to track the emission periods of O3 precursors. Then the updated OSAT module was applied to investigate the spatial-temporal contribution of precursors emissions to the O3 concentration over the GBA in July and August 2016, when several O3 episodic cases appeared in this period. Overall, the emissions within GBA, from other regions of Guangdong province (GDo), and the neighbouring provinces are the three major contributors, which account for 23 %, 15 %, and 17 % of monthly average O3 concentration, respectively. More than 70 % of O3 in the current day is mainly formed from the pollutants emitted within 3 days and the same day’s emission contributed approximately 30 %. During the O3 episodes, when typhoon approached, more pollutants emitted 2–3 days ago from the GDo and adjacent provinces were transported to the GBA, leading to the increase of O3 in this region. Under the persistent influence of northerly wind, the pollutants originating from eastern China earlier than 2 days ago can also show an obvious impact on the O3 over the GBA in the present day, accounting for approximately 12 %. On the other hand, the O3 pollution is primarily attributed to the local emission within 2 days when the GBA is mainly under the influence of the sub-tropical high-pressure systems. These results indicated the necessity to consider the influence of meteorological conditions in implementing the control measures. Meanwhile, analogous relationships between source area/time and receptor were derived by the zero-out method, supporting the validity of the updated OSAT module. Our approach and findings could offer more spatial-temporal information about the sources of O3 pollutions, which could aid in the development of effective and timely control policies.

Yiang Chen, Xingcheng Lu, and Jimmy C. H. Fung

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-3140', Anonymous Referee #2, 04 Mar 2024
  • RC2: 'Comment on egusphere-2023-3140', Anonymous Referee #1, 11 Mar 2024
Yiang Chen, Xingcheng Lu, and Jimmy C. H. Fung
Yiang Chen, Xingcheng Lu, and Jimmy C. H. Fung


Total article views: 284 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
221 51 12 284 20 3 5
  • HTML: 221
  • PDF: 51
  • XML: 12
  • Total: 284
  • Supplement: 20
  • BibTeX: 3
  • EndNote: 5
Views and downloads (calculated since 19 Feb 2024)
Cumulative views and downloads (calculated since 19 Feb 2024)

Viewed (geographical distribution)

Total article views: 301 (including HTML, PDF, and XML) Thereof 301 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 19 Apr 2024
Short summary
This study investigates the contribution of pollutants from different emitting periods to ozone episodes over the Greater Bay Area. The analysis reveals the variation of major spatiotemporal contributors to the O3 pollution under the influence of typhoons and sub-tropical high-pressure. Through the temporal contribution analysis, our work offers a new perspective on the evolution of O3 pollution and can aid in developing effective and timely control policies under unfavorable weather conditions.