Smog makes air thick and hard to breathe. It also changes the way light and color look to the naked eye. In a recent study in the the journal Proceedings of the National Academy of Sciences, climate scientists found that impressionist painters in 20th-century London and Paris were capturing the effects of air pollution through their art through contrasting colors and hues. The World’s Carol Hills speaks to Anna Lea Albright, atmospheric scientist at the Laboratory of Dynamic Meteorology in Paris about the research.