California activists paved the way for defining climate change as an air pollution problem—now it's federal law. Connecting climate change with something visceral and dangerous brings more immediacy to a problem that’s often seen as unfolding far away or in the future, even though it’s causing suffering now. “Climate pollution” is becoming common on the websites of green groups and atop news stories. It wasn’t always a popular move to link global warming with air quality. Environmental justice activists in California tried to popularize the phrase “climate pollution” starting around 2012. Framing climate change as an air quality problem is good persuasion strategy (as research shows), and it also validates long-standing concerns from communities that are threatened by industrial pollution.