A scientist driven to solve intertwined climate and pollution problems

As told to Beth Jensen 

I was born and raised in central China in a city called Zhengzhou in Henan Province. I always liked math and natural sciences, and I grew to love chemistry in particular. It seemed magical to me that I could combine a few substances and get a new substance with entirely different properties. 

My goal was to become a chemist until I realized during titration experiments in high school that I couldn’t tell when the colors changed. Like my grandfather, I was partially colorblind, and that ruled out chemistry as my college major. I decided to study computer science, but after an internship in my senior year, I knew a programming job wasn’t for me. 

I wanted to apply my computer skills to address real-world issues, and that led me to atmospheric science. I felt the effects of environmental changes in my own family and community, and I knew the world’s most powerful computers are devoted to weather forecasting and climate simulations. 

My hometown and other cities in China were becoming heavily polluted. We woke on many winter mornings and couldn’t see the sun or blue sky all day. We all called it fog – we thought it was just humid. Now we know it was haze resulting from human-based emissions and pollution-trapping weather patterns. There were a lot of health issues for people in my region. My mom, who had never smoked, was diagnosed with lung cancer. It was clear to me that air pollution was a very urgent problem that needed to be taken care of. 

Dramatic weather patterns in my hometown added to my sense that atmospheric science has a direct connection to daily life. The city lies about 500 miles inland and is usually pretty dry. But in summer, it occasionally experiences way more precipitation during some severe weather events, like thunderstorms, than cities near the coast, which can lead to flash flooding. 

Today my research primarily focuses on interconnections between climate change, air quality, and emissions from human activities. I’m particularly interested in aerosols, which are the natural or man-made droplets or solid particles suspended in the atmosphere that can be breathed in and impact your health – think car exhaust, industrial emissions, or dust. 

Aerosols are important for understanding both large-scale changes in Earth’s atmosphere and local impacts from severe weather events induced by global warming. My past research has shown that local petrochemical pollution around Houston, for example, contributed to the intensity of precipitation from Hurricane Harvey, and the area’s catastrophic flooding, and that air pollution flowing out of Asia can affect winter cyclones over the northwest Pacific Ocean. 

Aerosols are essential to cloud formation, and they can influence cloud properties. For example, adding aerosols into stratus clouds will make them brighter by reflecting solar radiation back into space, which in turn provides a cooling effect. That’s part of why some researchers are exploring the idea of temporarily mitigating global warming by spraying aerosols into different parts of Earth’s atmosphere. 

But weather models still do not fully account for the effects of aerosols, and climate models capture aerosol impacts very crudely. My research goal is to better understand how aerosol emission reduction changes our weather extremes and climate, and to make sure our future weather and climate projections fully incorporate atmospheric composition information. 

We are dealing with two crises simultaneously: climate change and air pollution. These are dynamic challenges, but through state-of-the-art computer modeling, artificial intelligence, and satellite remote sensing techniques we’re understanding more and more, and I’m happy to contribute to solving the problems. 

Related: Yuan Wang, Assistant Professor of Earth System Science