NIWA study maps air quality in Invercargill

A new study from NIWA mapping outdoor air quality in Invercargill reinforces why burning dry wood and switching to electric heating will help the city breathe easier.

In July, 44 air quality clarity instruments monitoring levels of pollutants PM2.5 and PM10 levels were installed within a two kilometre grid in south Invercargill as part of NIWA’s Clarity project. In mid-August half of the sensors were moved to cover the rest of the city.

Environment Southland air and terrestrial science team leader Nick Talbot says the Council contributed funding to the first part of the study to understand the concentrations of pollutants that we breathe in daily from fireplaces, industrial sources and vehicles.

The data from this project models how smoke plumes typically move and provides a broader picture of pollution levels across Invercargill. They found that outdoor air in the most polluted locations contained three times as much particulate matter – from smoke and other pollutants – as the air in the least polluted areas.

“Although south Invercargill has the highest concentrations, not all the pollutants have come from that area. Instead the data shows, on cold, still nights the pollutants from other parts of Invercargill will accumulate in south Invercargill due to the airflow pushing them from north to south.”

Home heating remains the area where people can make the biggest difference to air quality, he said.

“Our message continues to be to burn dry wood hot and bright, don’t bank your fires overnight and make sure to get your chimney cleaned regularly.”

The second part of NIWA’s study looked at how much of this pollution is getting into people’s houses.

Working alongside local community organisation South Alive, NIWA installed air quality monitors in the homes of six volunteers to collect data every few minutes on levels of particulate matter. This enabled the scientists to work out whether indoor air was being contaminated from inside or from outside the home, or both.

“NIWA’s work shows that poor air quality outside often drifts indoors which is detrimental to peoples’ health and wellbeing. Environment Southland plans to use this information to work with other advocacy groups to help lower air pollution levels and make homes healthier,” Nick Talbot says.

“The solution to Invercargill’s air quality problems needs to be a joint one because it is not just an environmental problem but a socioeconomic and health one too.”

Environment Southland operates a Good Wood approved suppliers scheme which firewood retailers can sign up to voluntarily, and agree to certain standards for their wood. Details of which can be found online.

For further information on what else you can do to improve air quality, go to www.BreatheEasySouthland.co.nz.

For more information, please contact the communications team on 0800 76 88 45.