Air pollution

“Most air pollution comes from energy use and production,” says John Walke, director of the Clean Air Project, part of the Climate and Clean Energy program at NRDC. “Burning fossil fuels releases gases and chemicals into the air.” And in an especially destructive feedback loop, air pollution not only contributes to climate change but is also exacerbated by it. “Air pollution in the form of carbon dioxide and methane raises the earth’s temperature,” Walke says. “Another type of air pollution, smog, is then worsened by that increased heat, forming when the weather is warmer and there’s more ultraviolet radiation.” Climate change also increases the production of allergenic air pollutants, including mold (thanks to damp conditions caused by extreme weather and increased flooding) and pollen (due to a longer pollen season).

“We’ve made progress over the last 50 years improving air quality in the United States thanks to the Clean Air Act,” says Kim Knowlton, senior scientist and deputy director of the NRDC Science Center. “But climate change will make it harder in the future to meet pollution standards, which are designed to protect health.”