New Zealand’s unhealthy home-heating in the age of COVID-19: Part 4 Has COVID-19 lockdown changed the risk from woodsmoke?

Winter 2020 may be different to previous winters. During level-4 lockdown, many more people were at home for more hours of the day. This was probably little changed in level-3. It is plausible to assume not only does this mean more people spending extended time in places where they are likely to be inhaling woodsmoke, it also means fireplaces are on for longer, more wood being burned and more smoke in the air.

Home heating emissions usually start to impact air quality from around mid-April, with each cold snap being a little colder and PM10 levels a little higher. At the time of writing, PM10 levels across communities with well-known woodsmoke issues “appear” (at first glance) to be about normal for the time of year, or maybe very slightly down. However, deducing what is happening with emissions (the amount of smoke being released from chimneys into the air) from air quality data (how concentrated that smoke is after its been diluted, transported and reaches a monitor, or someone’s nose) alone is surprisingly difficult. On a day-to-day basis air quality varies hugely depending on the weather - especially the wind speed. Each year people will discuss how winter has come early, or late, or is warmer/colder than normal. It really takes several weeks or even months of data before analysts can draw even tentative conclusions about whether fluctuations in air quality means that emissions have changed or if the variation is just a reflection of capricious weather.

PM10 in Invercargill during level-4 (orange) and level- 3 (yellow) in 2020, and same weeks in 2019

These are some of the reasons why NIWA’s “CONA” research project exists. The Community Observation Networks forAir project was born in 2015. It’s aim is to explore how new technologies might increase our understanding of local air quality – mainly by expanding what can be observed – and trial how that understanding can be used by communities to accelerate solutions. Over the last five winters the NIWA team have developed new techniques for using low-cost sensors in the streets and in the home for tracking the sources and movement of smoke across towns. We have also experimented with using apps to enable local householders and schoolchildren to capture data on who the smoke is affecting.

An ODIN in Arrowtown

After a successful project in Arrowtown in 2019, the NIWA team were almost ready to return to the town, this time recruiting a team of local volunteers to help run the project and begin some small intervention experiments. But COVID-19 beat us to it. The virus, and the lockdown – whilst frustrating – provided us with some new research questions and opportunities. As we emerge from level-3 into level 2 this week, the NIWA team is getting ready to get back to work.

What happens with woodsmoke emissions during level-2 and beyond depends on whether we need to return to level-3 or 4, and on the economic fallout from lockdown. How many people who would normally be out working now be stuck at home? How many will find themselves unable to afford wood and find themselves condemned to the double risk of a cold home but no escape from their neighbour’s smoke?

Our first tasks include launching an app that anyone can use to report the impact woodsmoke is having on them. This is intended to start building up a picture of these previously unreported ‘invisible’ impacts, and possibly identify locations which need special attention in the future.

NIWA's Citizen Science app

Once fieldwork can re-start in earnest, we intend to pay particular attention to helping communities to monitor their own wood consumption, smoke emissions and impacts. This then provide a platform for developing, trialling and perfecting solutions to creating healthy communities that also provide safe havens from environmental hazards.