The Environmental Protection Department on Friday downplayed concerns that Hong Kong's air pollution will get worse once the Covid-19 situation stabilises and the economy picks up further.
Latest figures show monitoring stations recorded higher levels of nitrogen dioxide last year than in 2020 when the pandemic began.
But Assistant Director of Environmental Protection Kenneth Leung said despite the recovering economy in 2021, Hong Kong still managed to keep pollutant levels lower than pre-pandemic days.
“All the others, for example, the PM 2.5, they are virtually flat. That means even in 2021, with less Covid impact, the PM levels could maintain at a relatively low level. But definitely, Covid has a lot more impact [on] NO2,” he said.
“It reduces a lot of emission in the transportation sector, and definitely the impact in 2020 is much higher than the other year, that's why we see a bounce back."
Leung added that people should not focus on changes within one or two years, and instead, look at long-term trends to gauge the city’s air quality.
According to government data from roadside monitoring stations, the average concentration levels of major air pollutants, including nitrogen dioxide, fine suspended particulates (PM 2.5), respirable suspended particulates (PM 10), and sulphur dioxide, dropped 43 to 58 percent between 2011 and 2021.
Still, most pollutant levels are far from the latest air quality standards set by the World Health Organisation.
Leung did not say exactly when Hong Kong will be able to meet these standards.
“It depends on a lot of things, for example, the migration or transformation of our vehicle fleet towards completely zero carbon emission. It is a very challenging task,” he said.
“We hope by 2025, we will have a much clearer timeline, as well as roadmap.”
But by that time, he said, officials hope to see a downward trend in ozone levels that have continued to rise.
“It is a regional issue. It could not be resolved simply by reducing our emission,” Leung said.
“If [we] don’t collaborate with Guangdong or other regional cities, our ozone will rise...it’s a must, in terms of improving ozone, to collaborate with our partners in [other] cities.”