Canada Wildfire Maps as U.S. States Face 'Unhealthy' Air Quality

Wildfires are scorching large areas of Canada's British Columbia and Northwest Territories, sending plumes of smoke billowing across the northwestern U.S. states.

NASA maps show the extent of the blazes, with nearly 400 fires burning in British Columbia alone, and about 1,000 fires burning across the country, according to the Canadian Interagency Forest Fire Centre (CIFFC).

This smoke has led to the air quality across Washington, Oregon, Idaho and California being classified as "unhealthy" on the U.S. Air Quality Index (AQI).

So far this year, Canada has seen over 14 million hectares burned by wildfires, around 10 times more than in 2022. Over 30,000 homes have been evacuated in British Columbia this week, and four firefighters have died.

Out of the reach of the flames, these fires are causing harm via the thick toxic smoke emanating from the wildfires that's being blown across Canada and the U.S.

"The biggest problem with wildfires apart from the immediate danger is the decrease in air quality," Mark Maslin, a professor of earth system sciences at University College London, previously told Newsweek. "This is very severe because the soot and smoke can cause huge issues [for] people with sensitive respiratory diseases."

Air quality monitoring shows that the AQI in parts of Washington state, Oregon, Idaho and California exceeds 150, taking it into "unhealthy" territory. The AQI is a scale of fine particulate matter (PM2.5) in the air that runs from 0 to 500, with levels over 150 being classed as "unhealthy," over 200 being "very unhealthy," and over 300 being "hazardous."

AQI levels of over 250 have been recorded in some parts of northern Washington, according to the the World Air Quality Project.

PM2.5 particulates are 2.5 micrometers or less in diameter, and include substances such as soot or black carbon, as well as ammonia, sodium chloride, mineral dust and water. These may cause irritation to the nose, eyes, lungs and throat, and an increased chance of respiratory infection.

"We know that the longer the smoke is in the atmosphere—aging—there is a greater risk of chemical changes creating more free radicals that are highly reactive and have the potential to cause adverse health effects," Christopher Migliaccio, a research associate professor in toxicology at the University of Montana, told Newsweek in April.

"Both respiratory and cardiovascular at-risk people can have complications from large smoke exposures. These include exacerbation of asthma/COPD and increasing risk of a cardiovascular event," Migliaccio said.

As the fires continue to burn, thousands of people have been displaced from their homes, and thousands more will be impacted by the smoke.

Climate change is thought to be a major driver of these record-breaking fires.

"Extreme weather is the by far the dominant cause of this record-breaking fire season currently occurring in Canada," Apostolos Voulgarakis, a professor of climate change at Imperial College London and AXA chair in wildfires at the Technical University of Crete, told Newsweek previously.

"Summers with more intense droughts and heat than average have always existed, but the key for explaining what is happening right now is that these naturally occurring phenomena are pushed to new extremes due to climate change, which is causing more and more destructive phenomena around the world as it unfolds."

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