Dr. Lyu won the Public Policy Research (PPR) funding of HK$648,255.00 from the Chief Executive's Policy Unit (特首政策組) of HKSAR. The proposal entitled 'What Are the Implications of COVID-19 Restrictions for Ozone Pollution Control in Hong Kong?' aims to study the changes in ozone polution and ozone formation chemistry in response to different levels of COVID-19 restrictions in mainland and HK.

The innovation of this project lies in two aspects. First, the idea of comparing the impacts of COVID-19 restrictions on ozone pollution between Guangdong and Hong Kong is novel. Although the COVID-19’s implications on ozone air pollution control were extensively studied, the effects of different levels of restriction were seldom explored. The comparison will tell ‘a tale of two cities’. Moreover, while some studies shed light on the impacts of COVID-19 lockdown on transboundary transport of ozone, the resulting changes in ozone formation regime and sensitivity in downwind regions were not studied. Second, explainable machine learning (ML) will be applied to the large amounts of observational data in Guangdong and HK. With the ML, we will deconvolve the complicated factors that shaped the changes in ozone and ozone precursors during the COVID-19 restrictions.