Air pollution

Tens of millions of Americans, including many Texans like me, live in counties that will soon be violating air pollution particle standards for the first time. It’s not that our air is getting dirtier – it’s because the U.S. Environmental Protection Agency just tightened its cap on the deadliest air pollutant: fine particulate matter, or PM2.5. The EPA acted because the Clean Air Act requires it to periodically review existing standards for six major air pollutants to ensure that the targets protect public health. Its 2022 scientific review showed that fine particles increase rates of illnesses and death even when inhaled at levels below existing standards. The EPA estimates that meeting its new standard would yield up to US$77 in health benefits for each $1 of control costs and would save up to 4,500 lives in 2032. Now, states must develop plans that meet the standard. As an atmospheric scientist who has studied air pollution for a quarter century, I’...

The Biden administration has frozen pending decisions on permit applications to export liquefied natural gas, or LNG, to countries other than U.S. free trade partners. During this pause, which will last for up to 15 months, the administration has pledged to take a “hard look” at economic, environmental and national security issues associated with exporting LNG. Environmental advocates, who have expressed alarm over the rapid growth of U.S. LNG exports and their effects on Earth’s climate, praised this step. Critics, including energy companies and members of Congress, argue that it threatens European energy security and energy jobs in the U.S. Emily Grubert, associate professor of sustainable energy policy at the University of Notre Dame and a former official at the U.S. Department of Energy, explains why large-scale LNG exports raise complex questions for U.S. policymakers. Is the US a major LNG supplier? The U.S. is now the world’s largest LNG exporter...

Air pollution particles from coal-fired power plants are more harmful to human health than many experts realized, and it’s more than twice as likely to contribute to premature deaths as air pollution particles from other sources, new research demonstrates. In the study, published in the journal Science, colleagues and I mapped how U.S. coal power plant emissions traveled through the atmosphere, then linked each power plant’s emissions with death records of Americans over 65 years old on Medicare. Our results suggest that air pollutants released from coal power plants were associated with nearly half a million premature deaths of elderly Americans from 1999 to 2020. It’s a staggering number, but the study also has good news: Annual deaths associated with U.S. coal power plants have fallen sharply since the mid-2000s as federal regulations compelled operators to install emissions scrubbers and many utilities shut down coal plants entirely. In 1999, 55,000 death...

Humans have contended with dust storms for thousands of years, ever since early civilizations appeared in the Middle East and North Africa. But modern desert dust storms are different from their preindustrial counterparts. Around the world, deserts now increasingly border built structures, including urban dwellings, manufacturing, transportation hubs, sewage treatment and landfills. As a result, desert dust lifts a growing load of airborne pollutants and transports these substances over long distances. This is happening throughout the Global Dust Belt, an arid to semiarid region that stretches from western China through Central Asia, the Middle East and North Africa. Similar storms occur in the U.S. Southwest and central Australia. Global pattern of dust frequency estimated from weather records, 1974-2012. Shao et al., 2013, CC BY-ND To our thinking, modern desert dust storms have been overlooked...

Canada’s seemingly endless wildfires in 2023 introduced millions of people across North America to the health hazards of wildfire smoke. While Western states have contended with smoky fire seasons for years, the air quality alerts across the U.S. Midwest and Northeast this summer reached levels never seen there before. The smoke left the air so unhealthy in Philadelphia on June 7, 2023, that the Phillies-Detroit Tigers Major League Baseball game was postponed. That same week, New York City residents hunkered down indoors for several days as a smoky haze hung over the city, turning the skies orange and exposing millions of people to the worst air quality in the world. Smoke also drifted into the Midwest, triggering the highest air quality index levels in the Chicago area in at least 24 years, forcing the cancellation of numerous summer activities and leaving residents with raspy voices. In several states, people woke up to smoky skies day after day....