Experts say possible small drop in Brisbane pollution but more data needed

Experts have weighed in on whether or not Queensland’s coronavirus lockdown is having a positive impact on Brisbane’s air and traffic pollution levels, but opinions are divided. SEE THE DATA.

TRAFFIC-RELATED air pollution in Brisbane has dropped amid coronavirus movement restrictions, experts say, however not as dramatically as in other more polluted parts of the world.

Environmental engineer and Director of Katestone Simon Welchman told The Courier-Mail March data suggests that there has been a reduction in traffic-related air pollutants such as nitrogen dioxide and PM2.5.

Himalayas becomes visible as pollution levels drop

Himalayas becomes visible as pollution levels drop

“There appears to also be a change in the time of day when air pollutants are being emitted,” Mr Welchman said.

“Normally, we’d expect the peaks to occur in the morning on weekdays. In March this year, that peak is less distinct.

“April will probably provide an even clearer picture as to the degree of improvement in air pollutants that have resulted by the current restrictions.”

A graph showing air pollution in Brisbane in March 2020 in relation to the same time last year.

Shocking satellite imagery shows air pollution levels plummeted in China and parts of Europe amid coronavirus lockdowns during February and March.

In India, a nationwide curfew and lockdown since March 24 has resulted in significant improvement in air quality in the country and clear skies not seen for decades in New Delhi.

Any changes in air pollution in Queensland will likely be far less dramatic.

“Air quality in Brisbane, and Australia more generally, is very good,” Mr Welchman said.

“We don't have the very high levels of air pollutants that we see in China and other parts of the world. Consequently, the improvement is less dramatic.

“It remains to be seen just how significant the reduction in Australia will be, but we are lucky to be starting from a very good base.”

Light traffic is seen on the Riverside Expressway during the morning peak hour in central Brisbane on Friday, March 27. Picture: AAP/Dan Peled

Director of the International Laboratory for Air Quality and Health Professor Lidia Morawska told The Courier-Mail her team had not yet observed “basically any difference” in air quality across Brisbane.

“Based on what we see visually looking at the data we don’t see basically any difference, which we are not surprised with because first of all Brisbane and the whole of South East Queensland is not in lockdown as such,” Professor Morawska said.

“It’s not like life has stopped.

“There is still a lot of traffic; people going to shops, doing their business. Importantly, heavy transport vehicles still operate, so there is not such a dramatic difference in traffic than it was in other countries like in China or Italy where there was a complete lockdown.”

Professor Morawska said even in the case of a full lockdown in Queensland, air quality changes would not be dramatic, however some isolated pockets could see noticeable changes.

“Let’s say if you focused on a specific hotspot or specific road that is normally busy but is not now, the picture would be very different,” she said.