Faculty Spotlight: Scot Miller, PhD

Meet Scot Miller, PhD

Home town: Fargo, North Dakota
Favorite class to teach: Case Studies in Climate Change - A Field Course (EN.570.320)
Fun Fact: An ultramarathoner, Miller once completed a 100-mile hike along the Wind River Range in Wyoming.

What are your research and teaching interests? 

I want to understand emissions of greenhouse gases and air pollutants – from the scale of individual cities up to the entire globe. Most state and national governments estimate emissions using inventories. To make inventories, governments count up the number of cars on the road emitting carbon dioxide, the number of cows burping methane, or the miles of leaky natural gas pipelines. These inventories, however, can overlook hidden processes that produce emissions. I use observations of these gases that are collected in the atmosphere to estimate emissions at the Earth's surface. When we observe greenhouse gases from aircraft or satellite, we can see all the emissions across the landscape, even emissions that an emissions inventory may have overlooked. 

Why did you choose this field? 

When I first started college, I took a freshman seminar on research at the Harvard Forest. Every Friday afternoon, we would drive out to central Massachusetts, stay in an old house in the woods, and tour around the forest learning about different research projects aimed at understanding how the forest has been evolving. At the time, the forest was taking up more and more carbon per year and was acting as a larger and larger CO2 sink, a phenomenon that scientists were trying to understand.  

I remember climbing one of the towers in the forest where scientists made measurements of CO2. From the top of the tower, you could see over the forest canopy for miles in every direction, and you could almost imagine the forest breathing in and out CO2. I never knew how intricate and complex forests can be. I wanted to understand how forests work and how they take up or release CO2 into the atmosphere. Unfortunately, the trend that scientists saw at Harvard Forest in the early 2000s has now reversed. The forest is taking up less and less CO2 per year, largely because an invasive pest called the woolly adelgid is slowly killing the stately hemlock trees that used to be widespread from North Carolina up to Nova Scotia. 
 
With that said, my path to becoming a scientist has been anything but linear. After college, I worked at a consulting firm in Germany and took the LSAT exam with the intent of applying to law school. I missed hiking in the woods and spending at least part of my career outdoors. 

What's something about your research that you're excited to share with students? 

I think it's really exciting that scientists can now monitor greenhouse gases from satellites. These measurements are arguably extremely difficult to make from satellites; satellites can't observe greenhouse gases directly but rather measure variations in infrared radiation that are subsequently converted to observations of different greenhouse gases through a complex set of algorithms. I remember working on my undergraduate thesis in the early 2000s, and there were roughly five to 10 long-term greenhouse gas monitoring sites across the Continental U.S. We now have millions and millions of greenhouse gas observations across the globe from satellites, a revolution in data that is transforming our understanding of greenhouse gases. 

Tell us about something you’re proud of accomplishing. 

A PhD student in the group, Dylan Gaeta, recently published a study that I'm very proud of. Dylan looked at emissions of a relatively overlooked greenhouse gas called sulfuryl fluoride. This gas is a pesticide that is used for fumigation, and scientists only recently learned that it is a potent greenhouse gas. We found that most sulfuryl fluoride emissions from the U.S. are from the state of California, in part because California has a unique species of termite that is traditionally treated using this gas. Historically, California has been more proactive in tracking its greenhouse gas emissions than almost every other state, but this gas flew under the radar. 

 What do you like about living in Baltimore? 

I love living in Baltimore. I love how old, quirky, and bohemian the city is. I also love how walkable and bikeable the city is. Many years ago, my older sister and I made a bet to see who could last the longest without buying a car. I've now won that competition by 15 years, thanks in part because Baltimore is such a great city for biking. 

What’s something your colleagues/students might be surprised to learn about you? 

I grew up in Fargo, North Dakota. My aunt and uncle ran a cattle ranch near the Missouri River in North Dakota, and I spent many holidays helping them out on the ranch. Thirty years later, I still work on cattle, though from a very different perspective – by studying how much methane they burp into the atmosphere and how farmers or ranchers could mitigate those emissions. 

What do you like to do outside of work? 

I like to be in the woods or spend my weekends somewhere under the stars. I became a scientist because I wanted to be closer to the outdoors and to understand everything I see from the trail. 

Environmental Health and Engineering is a cross-divisional department spanning the Bloomberg School of Public Health and the Whiting School of Engineering. This hybrid department is uniquely designed to lead pioneering research and prepare the next generation of scholars and professionals to solve critical and complex environmental issues. Learn more about our programs.