Even as an air pollution expert, these months of bushfire smoke have been a shock


The terrible air quality from this season’s bushfires is unmatched in terms of severity, duration and extent. Tourists take a selfie wearing face masks. Photograph: Jenny Evans/Getty Images

Smoke from this season’s bushfires has turned the sun red, the moon orange and the sky an insipid grey. It has obscured iconic views tourists flock to see. Far more than an aesthetic problem, it has forced business shutdowns, triggered health problems and kept children indoors for weeks.

City dwellers in south-east Australia have been forced to take a crash course in the finer points of air pollution. We’ve learned about the dangers of inhaling tiny PM2.5 particles (those 2.5 microns or fewer in diameter). We’ve learned that only a close-fitting P2 mask will do much to protect us.

Still, we wear disposable paper masks and hold handkerchiefs to our faces, hoping any amount of filtering is helpful.

Even for an historian of air pollution like me, this situation is a shock. It is not the first time Australia’s major cities have been shrouded in bushfire smoke. But the terrible air quality is unmatched in terms of severity, duration and extent.

Historically, air pollution from smoke was considered outside human control and not subject to regulation. But these bushfires are clearly linked to global warming, for which government, corporations and individuals are responsible. It’s time to rethink the way we protect air quality.

The history of smoke

In recent weeks, apps such as AirVisual have confirmed what we city dwellers can already see and smell: since the fires on the north coast of New South Wales began in late October, our air quality has plummeted.

The NSW government’s Air Quality Index data has shown that since late October, days when the index was higher than 100 – signalling exposure is unhealthy – have outnumbered clear days in Sydney, Newcastle and the Illawarra.