Overview
- An international team led by the University of Waterloo published modeling in Environmental Science & Technology that forecasts routine unhealthy air for sensitive groups across much of the United States by century’s end.
- The researchers estimate a sevenfold jump in people living with regular air-quality alerts, rising from about 14 million in 2000 to roughly 100 million by 2100.
- The projected risks come from ground-level ozone and fine particulate matter, which increase with hotter temperatures and stagnant weather that keeps pollution near the ground.
- California and the Eastern United States face the steepest declines in smog-season air quality, with longer and more frequent stretches that trigger alerts.
- For older adults and people with heart or lung disease, alerts could occur about half of all days, which could mean roughly 142 extra days spent indoors each year, and the authors call for stronger building filtration, clean indoor public spaces, and more targeted alerts.