A new study published in PNAS shows that reducing climate change could save tens of thousands of lives in the United States each year by lowering deaths caused by wildfire smoke. Scientists analyzed future climate scenarios and found that keeping the global mean surface temperature (GMST) at 1.5 degrees Celsius above pre-industrial levels (1850–1900) could prevent up to 10,000 or more deaths annually in the U.S.
The global mean surface temperature (GMST) is now about 1.3 to 1.4 degrees Celsius above past levels. If warming continues at the same speed, it could rise to 3 degrees Celsius. This higher temperature would make wildfires worse. In North America, wildfires have increased a lot over the last ten years. Smoke from these fires contains tiny harmful particles and pollutants. These particles can travel very far in the air. As a result, many people are exposed to serious health risks. Despite its danger, estimates of the social and economic costs of climate change rarely include wildfire smoke.
The new research, led by Minghao Qiu, PhD, Core Faculty Member in the Program of Public Health and Assistant Professor in the School of Marine and Atmospheric Sciences (SoMAS) at Stony Brook University, addresses this gap. The team developed a comprehensive framework to estimate air pollution from climate-induced wildfire smoke and the resulting mortality in the U.S. across different greenhouse gas emission paths and temperature increases.
Their method also incorporates fire-vegetation feedbacks—the way past fires affect future vegetation and fire risk. Many previous studies overlooked this factor, which is considered a major uncertainty in predicting future wildfire impacts. To build their models, the researchers used 28 global climate models to create over 700 possible future scenarios.
Under a 3-degree Celsius warming scenario, the team estimates that annual wildfire-smoke-related deaths in the U.S. could reach 64,000, a 60 percent increase compared to deaths recorded during 2011–2020. Professor Qiu emphasizes, “This is a very dangerous trend, but lives can be saved if we reduce greenhouse gas emissions through energy, transportation, and climate policies.”
The study also examined scenarios with limited warming. Keeping global warming to 2 degrees Celsius could reduce smoke-related deaths by around 9,000 per year. Limiting warming further to 1.5 degrees Celsius could prevent approximately 11,600 deaths annually.
The research also estimates the economic impact of wildfires. When considering the monetized cost of mortality, climate-induced wildfire smoke could cause health damages worth hundreds of billions of dollars each year. The study calculates that each ton of carbon dioxide (CO₂) emitted in 2025 carries a net present value of $11.2 in wildfire smoke-related health damages in the U.S. Incorporating wildfire smoke into climate damage assessments increases the domestic cost of carbon by 74 percent, highlighting the greater benefits of reducing greenhouse gas emissions.
Scientists also looked at how past fires affect future fires. They found that areas that have already burned are a little less likely to burn again. This improvement does lower the risk slightly. However, it is not strong enough to stop the expected increase in wildfires, smoke pollution, and deaths.
The researchers say these findings are important for U.S. climate policy. They argue that climate planning tools should incorporate wildfire smoke. The damage from wildfires is enormous. It affects both public health and the economy. Because of this, they say wildfire damage must be a key part of climate action planning in the United States.
This study demonstrates the strong connection between climate change and human health. It shows why we must act quickly. We need strong action to slow down global warming. We must also cut harmful emissions. These steps can save thousands of lives each year.They can also reduce the big economic losses caused by wildfire smoke.
