While wildfire smoke is known to worsen air pollution, a new study reveals a surprising effect of wildfire heat. The heat from western US wildfires can actually improve air quality in the east by altering weather patterns and increasing rainfall.
Wildfires have become more frequent and severe around the world. These fires are driven by climate change and cause serious problems for health, the environment, homes, and the economy. Smoke from wildfires contains tiny particles that harm our lungs and heart, and these particles can travel long distances, sometimes even hundreds and thousands of miles.
According to the common belief, wildfires only make air pollution worse. In fact, smoke from wildfires in the western United States is thought to contribute to many early deaths in the eastern part of the country every year. But a new study has found something surprising. The heat from wildfires in the western US might actually help improve air quality in the east.
How Wildfire Smoke Affects Health
Wildfire smoke contains tiny particles called PM2.5. These particles can get deep into our lungs and bloodstream, causing breathing problems, heart disease, and even premature death. When wildfires burn in the west, the smoke drifts eastwards, carried by the wind. This makes air quality worse for many people far from the actual fires.
The Surprising Role of Wildfire Heat
The new study, published in the journal Science, looked more closely at what happens in the atmosphere when big wildfires burn. It shows that the heat from these fires changes the weather in ways that can help clean the air in the eastern US.
The intense heat from wildfires in the west causes warm air to rise quickly into the atmosphere. This rising air creates waves in the jet stream, a fast-moving current of air high above the Earth’s surface that affects weather patterns. Normally, the jet stream helps pull cool, moist air from the west across the country. This moist air usually mixes with winds coming from the Atlantic Ocean in the east, bringing rain that cleans the air by washing away pollution.
But due to a lot of heat, the waves in the jet stream weaken this usual flow of cool air from the west. This change lets more moist air from the Atlantic move island, causing more rainfall on the East Coast. And this extra rain helps remove harmful particles from the air, improving air quality.
How Did the Scientists Figure This Out?
The scientists studied air quality data from 2005 to 2015. They also used detailed computer models of the climate to see how the atmosphere might react to the heat and smoke from wildfires separately. They found that the heat plays an important role in changing weather patterns and reducing pollution on the East Coast.
Why This Discovery Matters
Most climate models only consider the smoke from wildfires, not the heat they produce. This means these models may overestimate the harm wildfires cause by ignoring the helpful effects of the heat on weather and rainfall.
The researchers warn that ignoring wildfire heat could lead to overestimating the number of premature deaths by 1,200 each year in the eastern US, and an overestimation of economic losses by about $3.3 billion.
Understanding the effects of wildfires, including the role of heat, means scientists can provide better information to decision-makers, health experts, and fire managers. The goal is not to say that the wildfires are “good” for the environment or health. Instead, this study shows the importance of looking at all their effects to understand how they influence the climate and people’s well-being.