68% of western US population affected by wildfires in one day

Research into the impact of major blazes and severe heat incidents found 43million people suffered the impact of harmful air pollution on a single day in 2020. 

 Washington State University (WSU) led on the study, which looked to assess whether or not western US states were seeing a reduction in atmospheric quality as a result of wildfire increases. 

According to the results, more than 68% of the region’s population had been impacted by air pollution during a 24-hour period during 2020, with this directly linked to uncontrollable blazes. This is the highest number of people affected in 20 years. 

The work, published in Science Advances, shows these widespread air pollution events were increasing in frequency, and lasting much longer. In turn this means they spread over a larger geographical area, and have the potential to reach more people. 

Tellingly, the situation has become so serious many gains created by the US Clean Air Act are now being reversed, and the trend is expected to continue as the conditions needed to trigger these events are becoming more commonplace, posing a major threat to human health. 

‘We have seen an increasing trend in the past 20 years of days when high-levels of both particulate matter and ozone are occurring simultaneously,’ said lead author Dmitri Kalashnikov, a WSU doctoral student. ‘This is tied to two things: more wildfires and increases in the types of weather patterns that cause both wildfires and hot weather.’

‘From every indication we have, the hotter, drier conditions projected for this region are likely to increase wildfire activity and contribute to more widespread, severe heat, which means we can expect to see these conditions happen more often in the future,’ said co-author Deepti Singh, a WSU assistant professor.

‘Preparing for these events is really important. We need to think about who is exposed, what capacity there is to minimize that exposure, and how we can protect the most vulnerable people,’ she continued. 

In related news, least year the American Geophysical Union warned the US ‘systematically underestimates‘ the health impact of wildfires. Meanwhile, Australian wildfires in the winter of 2019-20, which decimated around 27million hectares of land, produced so much smoke they blocked sunlight from Earth, and are thought to have been three times greater than any previously recorded event of this kind. 

Image credit: Marcus Kauffman