Re ECF Project: 2014-07

Project Title: Development of a rapid assessment tool for evaluating the effectiveness of emission control policies on ozone reduction

Applicant: Dr Steve YIM Hung Lam, The Chinese University of Hong Kong

Total Approved Grant: $1,419,480

Duration: 1/7/2015 to 31/12/2017

Project Status/Remarks: Completed

This project aims to develop a rapid assessment tool for policy makers to assess the effectiveness of a range of policy scenarios for reducing ozone concentration in a reasonable timeframe.

Summary of the Findings/Outcomes:
The project developed a rapid assessment tool [Ozone Assessment Tool (OAT)] capable of assessing changes in ozone (O3) in Hong Kong (HK) and urban areas in the Pearl River Delta region (Urb-PRD) in the year 2010 and 2030 due to changes in nitrogen oxides (NOx) emissions. A number of state-of-the-science atmospheric models were adapted and advanced to develop a model framework to compute O3 sensitivity with respect to changes in NOx emissions. A comprehensive set of O3 sensitivity maps for HK and Urb-PRD was generated, including annual and seasonal O3 sensitivity maps. The sensitivity results were analyzed to examine the influence of changes in NOx emissions and climate on O3 concentration and sensitivities in HK and Urb-PRD. The O3 sensitivity results show that the O3 in HK or in Urb-PRD were affected through direct transport of remote O3 or through local photochemical reactions under influences of local emissions and transported NOx. Moreover, prevailing wind directions may also influence O3 sensitivity. The future projections show that O3 tends to increase in 2030 comparing with 2010, while O3 tends to respond differently in future climate. Hot-spot locations, in which O3 is relatively sensitive to changes in NOx emissions, were identified. The sensitivity results were then used to develop OAT.