Wildfire smoke is erasing the air quality gains we've made since the 1970s. A new study from Columbia University Climate School found that climate-driven wildfires are increasingly dominating summer air quality across the United States and Canada, undoing decades of progress from pollution regulations. Unlike the sulfur dioxide and nitrogen oxide emissions that regulations successfully reduced, wildfire smoke cannot be controlled through industrial standards or vehicle emission rules. How Has Air Quality Changed Over the Past 70 Years? From the 1970s through the early 2000s, air quality improved significantly across the eastern US and Canada. Stricter regulations on industrial operations and vehicle emissions reduced harmful pollutants like sulfur dioxide and nitrogen oxides. But the trend reversed over the past 25 years as more severe wildfires and larger burned areas began pumping smoke into the atmosphere during summer months. The numbers tell a striking story. In 2023, smoke levels reached their highest point in 20 years of satellite measurements, and the number of smoke and haze reports hit a 70-year record. Twelve out of Canada's 13 provinces and territories set new wildfire smoke records in 2023. Even more concerning, only about half as much land burned in the following year, yet that would still qualify as a record-breaking year for any other time period. Why Can't Regulations Fix Wildfire Smoke Like They Did Other Pollution? The fundamental difference between wildfire smoke and industrial pollution is control. Regulations successfully reduced sulfur dioxide and nitrogen oxides by setting standards for factories and vehicles—sources that humans operate and can modify. Wildfire smoke, however, comes from uncontrolled natural disasters driven by climate change. As temperatures continue to rise, wildfires will become more frequent and intense, making this a public health challenge that traditional regulatory approaches cannot address. Steps to Prepare for Worsening Summer Air Quality - Improve Home Filtration: Installing high-efficiency air filters and using air purifiers indoors can reduce exposure to smoke particles during peak wildfire seasons, creating a cleaner breathing environment inside your home. - Monitor Air Quality Forecasts: Better smoke monitoring and forecasting systems help communities prepare in advance when air quality is expected to worsen, allowing people to plan outdoor activities accordingly. - Access Public Clean-Air Shelters: Communities are increasingly establishing public clean-air shelters where people can go during severe smoke events to breathe filtered air, particularly important for vulnerable populations like children and older adults. Scientists emphasize that long-term solutions require a multi-layered approach. "Better smoke monitoring and forecasting can help communities prepare when air quality is expected to worsen," according to the Columbia University Climate School research. Beyond immediate preparation, broader public health measures including home filtration systems and accessible public clean-air shelters will become increasingly important as wildfire seasons intensify. The shift from industrial pollution to wildfire smoke as the dominant air quality threat represents a fundamental change in how we need to think about environmental health. While we successfully regulated our way to cleaner air in the 20th century, the 21st century challenge requires both climate mitigation to reduce future wildfires and adaptation strategies to protect people from smoke we cannot prevent.
