Dozens of wildfires in Chile spurred authorities to issue evacuations on February 6, 2023. The fires have led to at least 26 deaths and almost 1,000 injuries (1), making the fires the deadliest in recent years.

In response to the disaster, firefighting teams from Latin American and European nations are arriving to help combat the flames.

The forested, hillside towns of coastal Chile are experiencing a severe heat wave during their Southern Hemisphere’s summer months, a phenomenon all too familiar to Europe and the Pacific Northwest during the northern summer of 2022. Elevated temperatures reaching as high as 104 degrees Fahrenheit dried out ground cover in Chile’s forest heartland. Tinderbox conditions can spark extreme, widespread wildfires, which are harder to control in hilly and mountainous terrain.

Over 667,000 acres of Chilean land have been burned by 275 active fires (2). The area burned is slightly larger than the U.S. state of Rhode Island.

Wildfires in Chile drive down air quality

Some affected areas by the Chile wildfires include the rural regions of Biobio, Ñuble, and Araucanía. The regions lie in the center of the narrow, mountainous country.

Less than half of the country’s forestry is in the Biobio region, making it a heavily wooded area. Neighboring Araucanía is home to several national parks and national reserves.

Beyond the intense, deadly threat of the forest fires themselves is the danger wildfire smoke poses to human health many miles away.

Wildfire smoke can travel thousands of miles from its source, crossing continents and even oceans. On Monday morning, northerly and northeasterly winds carried smoke as far north as Santiago, the nation’s capital city.

A complex of dozens of wildfires was pictured burning near Coronel, Chile, on Monday, February 6, 2023. Source: IQAir.

As fields, vineyards, and woodlands burn, PM2.5 laden smoke carries particles measuring 2.5 microns or less in diameter, high into the air. Because these particles are so small, they can be suspended for long periods of time and carried far distances.

They’re also tiny enough to enter the circulatory system when inhaled and have been linked to heart and lung disease.

Wildfire smoke was being blown northeast from its source, impacting distant cities like Talca, Curica. and San Fernando. Source: IQAir.

When there are high concentrations of PM2.5 in the air, air quality can be unhealthy or even hazardous. At 10 AM on Monday, an air quality monitor in Laja, a city near the inferno, measured hazardous concentrations of PM2.5, 289 µg/m3 (micrograms per cubic meter of air).

An air quality monitor in Hualqui also measured concentrations of PM2.5 at 279 µg/m3 by 2 PM.

Cities with the worst air quality in Chile on February 6 are either near or downwind from the wildfires. Source: IQAir.

The quality of the air was being measured by air quality monitors in regions north of the fire, including Maule and Libertador General Bernardo O'Higgins, just south of Santiago. Air quality monitors in Santiago measured air quality levels ranging from "Unhealthy for Sensitive Groups" to "Unhealthy."

Laja, Chile is one of the cities most affected by wildfire smoke on Monday. Air quality was hazardous in the morning. Source: IQAir.

Why are there so many wildfires in Chile?

Poor air quality and hazardous smoke are a natural consequence of numerous extreme wildfires, which are, in turn, generated and fueled by dry conditions. Chile is struggling with what the World Meteorological Organization calls the Central Chile Mega Drought, a 13-year period of record low rainfall (3). Chile’s mega-drought is also the longest such regional drought in a millennium.

Weather conditions are feeding the country's many wildfires. Firefighters are contending with the heat wave and powerful winds which have helped flames race across the countryside. These conditions are expected to persist through the week.

Regional wildfires were even more extensive in 2017 when 1,000 buildings in Santa Olga in the Maule region were burned down.

The takeaway

With our planet warming and a corresponding increase in mega-droughts, heat waves, and extreme wildfires, wildfire smoke poses an urgent, serious threat to human health in the coming years.

Even if you don’t live near wildfire country, the smoke’s long reach makes it important to know how to protect yourself from wildfire smoke. Close your windows and run an efficient air purifier at home when the air quality in your neighborhood is poor. If you must be outdoors, wear a KN95/FFP2 mask.