Dr Longley has been monitoring air quality in Auckland, Wellington and Christchurch since Level 4 restrictions were implemented and says working from home did not only cut emissions but could also reduce health risks.
After almost six weeks of monitoring air quality during Level 3 and 4 lockdown restrictions, scientist Dr Ian Longley is now asking people to record where and when woodsmoke is affecting their health and lives.
Traffic pollution measurements in Auckland since Level 4 restrictions were eased on Tuesday have shown levels soaring even higher than those before lockdown, NIWA air quality scientists say.Nitrogen oxides have also returned to pre-lockdown levels in Christchurch but not as dramatically as Auckland.
Air quality scientist Dr Ian Longley has analysed data from the third week of lockdown and found levels of nitrogen oxides, mostly caused by vehicle exhaust, have fallen between 83 and 91% of normal at most sites.
NIWA air quality scientist Dr Ian Longley says nitrogen oxide is found in pollutants from vehicle exhausts.Dr Longley says reductions in levels of airborne particulate matter have been more modest—for example a 20 per cent drop in fine particles (PM2.5) at Takapuna during daylight hours.
Dr Longley said concentrations started rising last Tuesday and Wednesday and by Thursday they were three to four times higher than normal across Auckland, Northland, Waikato, Manawatu and Hawke’s Bay. In summer particulate matter levels in New Zealand towns and cities are typically 10-20 micrograms per cubic metre.
That’s more than double the national standard of 50, with hourly concentrations peaking at 314 micrograms per cubic metre,” says project leader NIWA air quality scientist Dr Ian Longley.