Air quality fluctuations attributed to weather, not long-term decline: SMG

[Photo; Renato Marques]

Macau has recently experienced isolated instances of poor air quality, which authorities say were largely influenced by local weather conditions and regional pollution transport, rather than a deterioration in the city’s overall air quality.

Senior meteorological technician Chan Cheng Hou of the Meteorological and Geophysical Bureau (SMG) explained that these short-term fluctuations were “mainly due to unfavorable meteorological conditions for pollutant dispersion and the influence of regional pollution transmission. These were short-term, isolated incidents and do not represent a deterioration in Macau’s overall air quality.”

As cited in a TDM report, Chan noted that the city’s current Air Quality Index (AQI) has been in effect since 2021.

It is designed to provide an accurate reflection of the city’s environmental conditions by referencing the World Health Organization’s air quality guidelines and integrating standards from mainland China, Hong Kong, the United States, and other regions.

According to him, local circumstances are also considered in the calculations.

The AQI measures key pollutants, including 24-hour averages of particulate matter and eight-hour averages of ozone concentrations. An AQI reading exceeding 100 indicates poor or worse air quality, in line with international practices.

“The recent poor air quality levels were mainly due to the prevailing meteorological conditions, which were unfavorable for the dispersion of pollutants, as well as the influence of regional pollution transport,” Chan said.

“These were short-term, isolated incidents and do not indicate that Macau’s baseline air quality is at its worst. The SMG will continue to refer to the World Health Organization’s air quality guidelines and relevant standards from other regions, regularly reviewing the air quality index and adjusting standards as appropriate based on local conditions.”

The bureau added that these measures ensure consistent monitoring and public awareness, allowing authorities to respond to temporary pollution spikes.