Climate change exacerbates dust storms following wildfires — study

Photo by: Ghulam Hussain / iStock

Large wildfires cause dust storms in half the cases in areas affected by the blaze. This is the conclusion reached by scientists at the National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory in the US, science news portal Phys.org reports.

Researchers Yang Yu and Paul Jinu analysed more than 150,000 wildfires from 2003 to 2020.

Forest fires destroy vegetation, leaving behind a bare landscape that is very vulnerable to wind erosion and becomes a source of dust emissions.

Similar phenomena have previously been recorded in North America, but until now there have been no global studies on the strength and duration of dust storms in fire-scorched areas.

Scientists used satellite data on active wildfires to study the composition and characteristics of atmospheric aerosols, vegetation cover and soil moisture over 17 years.

The authors of the study found that about 90% of the large wildfires lasting seven consecutive days were associated with a significant reduction in vegetation cover. And more than 50% of these were accompanied by dust events in the following 60 days.

These dust storms often occurred in savannahs, which accounted for about half of the dust events following the fires.

These events can last from a couple of days to several weeks. Their intensity depends largely on the strength of the wildfires, including their duration, extent and impact on the vegetation cover.

Researchers have found that if there was a drought before the fire, dust storms were more likely to occur afterwards and were stronger.

Over the study period, the duration of dust events increased significantly as a result of increased regional wildfires and drought conditions due to climate change.

The authors of the study predict that future wildfires and associated dust events may become even more extreme as a result of the ongoing climate crisis.

According to the National Interagency Fire Centre, 2022 saw the highest number of wildfires in the US in a decade, with more than 56,000 fires covering about 2.8 million hectares across the country.

Studies show that chronic smoke exposure from wildfires can cause asthma and pneumonia, and increase the risk of lung cancer, stroke, heart failure and sudden death.

Cover photo: ChuckSchugPhotography / iStock