Hong Kong could get less polluted winter thanks to El Niño, as weather effect brings less mainland Chinese smog
- More rain and higher wind speeds help disperse pollutants
- City’s air quality tends to decline during autumn and winter as northerly winds bring mainland pollution
Hong Kong could experience a less polluted winter than normal if a strong enough El Niño weather effect whips up in the Pacific Ocean towards the end of what is typically the smoggiest season of the year, findings from a new study suggest.
The climate pattern describes the slight warming of sea surface temperatures over the eastern equatorial Pacific Ocean every few years due to the slackening of the trade winds across it. A La Niña effect brings the opposite.
According to Chinese University researchers, Hong Kong’s air quality is usually higher under El Niño conditions as the associated weather – more rain, less frequent northerly winds and higher wind speeds – tend to disperse pollutants.
The opposite was true for La Niña events, in which pollutant concentrations, especially from mainland China, were found to increase substantially.