Beijing, China
It’s well known that burning fossil fuels releases black carbon particles into the air, commonly called soot. But for the first time, atmospheric sciences professors Renyi Zhang and Don Collins, along with Ph.D. student Misti Levy Zamora ’10, pinpointed how much these particles impact air quality and climate. The team studied particulate matter over Houston and Beijing and found that as pollutants coat black carbon particles, they accelerate particle growth and create denser particles that absorb more sunlight in Beijing than Houston. This in turn heats the air and causes stagnation, which prevents air movement and results in the severe hazes common to Beijing.