Hannah Daley '17 is pursuing a doctorate degree in atmospheric and oceanic science from the University of Maryland. Here, she's pictured measuring aerosols and greenhouse gases by plane. (Courtesy photo)

Hannah Daley ’17 takes to the skies for air quality research

Hannah Daley ’17 has made scientific waves in the Eastern Mennonite University (EMU) community for years — investigating water quality in the Bergton area watershed, researching caffeinated athletes with James Madison University’s chemistry department, and studying atmospheric chemistry at the University of Michigan Biological Station. 

That last experience inspired her to enroll in the University of Maryland’s atmospheric and oceanic science doctoral program. Now, she’s making waves in the sky – measuring aerosols and greenhouse gases by plane. Her two current research projects are focused on the pandemic’s effect on airborne pollutants and a smoke plume that made its way to Maryland all the way from a West Coast wildfire. 

Daley spoke with EMU News about her work below.


What led you to the atmospheric and oceanic science program? 

I knew I wanted to study atmospheric science in the 8th grade. I went to EMU for its environmental sustainability program and its general sustainability campus culture. After my first year as an environmental sustainability major, I added a chemistry major. Throughout my time at EMU, I was fortunate to gain an exceptional amount of research experience, an opportunity I don’t think I would have had if I went to a larger university. My research experience and recommendations from exemplary faculty mentors like Professors Jim Yoder, Tara Kishbaugh, and Doug Graber Neufeld led to further research experience outside of EMU.

I was drawn to the University of Maryland (UMD) for a few key reasons. First, UMD is located within an hour of major government research agencies – including the National Oceanic and Atmospheric Administration (NOAA), NASA, the U.S. Environmental Protection Agency (EPA), and National Institute of Standards and Technology (NIST) — many of which are housed on campus in conjunction with the graduate department. The majority of graduate students actually hold their offices at these sites. 

Second, I am from Maryland, and it gave me the opportunity to be closer to my parents and many siblings — I am the youngest of six. Third, UMD is ranked ninth in the world for our geoscience programs. And fourth, I was drawn to the interesting research opportunity to perform fun, hands-on science.

Do you actually get to fly the planes that are collecting the data? 

I do not get to fly the plane! That would be fun, but the types of flights we do requires years of experience. We often fly low to the ground or at night through cities which can be dangerous for an inexperienced pilot. Our pilot Nizar is amazing! He has been flying for decades and now teaches people to fly. When I am on the flights I typically sit in the back and monitor the instruments to make sure everything is reading right.

What kinds of applications could come out of your assessments of carbon monoxide and carbon concentrations during Maryland’s lockdown?

When we talk about future climate or air quality, these are forecast assessments based on computer models. Many scientists spend their whole career tweaking these models for even the slightest improvement. And the accuracy of these models is based on how well models predict particular events. 

For example, how well do models predict hurricane track and intensity, or pollution transported from a smoke fire plume. During Maryland’s lockdown, how does a drastic decrease in traffic impact local air quality? This provided a unique event in which scientists can test how well models performed, and then improve them to be more robust. Air quality assessments could also lead to more informed policy decisions, which could potentially impact vehicle emission standards. 

For instance, Maryland recently released their greenhouse gas reduction plan, which aims to reduce carbon dioxide-equivalent emissions by 50% by 2030. During lockdown, traffic was roughly reduced by 50%. This gave us a unique opportunity to research how close Maryland would be to this goal if legislative and consumer decisions consistently reduced traffic by 50%, or if half of drivers switch to electric vehicles.

What’s interesting about the smoke plume? 

I am studying a smoke plume that originated over the US West Coast and reached Maryland on September 16, 2020. This plume was aged about 10 days and travelled thousands of miles to get to Maryland. That in itself is interesting to me! It’s just another fascinating reminder that we are all connected! 

I was the research scientist on board the aircraft as we were spiraling up to our planned peak height of 10,000 feet. I was stunned when I saw the instruments reading carbon monoxide and black carbon values two orders of magnitude higher than usual! I knew it would be an amazing data set if we could just fly vertically through the rest of the plume. Excited, I told the pilot what I was seeing, and he decided to keep flying up. We normally don’t fly higher than 10,000 feet because the aircraft is not pressurized, and we don’t want to be deprived of oxygen. Despite the drop in pressure, I stayed alert. We ended up reaching 15,000 feet above ground level and captured the whole plume’s vertical profile — 8,500 to 14,000 feet.

Smoke plumes can transport carbon monoxide, nitrogen oxides, particulate matter, and ozone, making air quality dangerous for many humans, animals, and plants. Fortunately, in this case study, the plume stayed high in the atmosphere and did not negatively impact the air we breathed at the surface. This smoke plume was unique in that the particles were very large and reflective. There was black, brown and organic carbon present. 

When analyzing the plume, I am looking to validate other instruments that monitor smoke plumes and to assess the unique chemical and physical properties of this plume. For instance, did the ground-based instruments accurately capture the plume’s height and density, and did our air quality models predict its composition? 

Do you know what kind of work you’d like to do after graduation?

One of my favorite parts of our group is how close we work with local and regional government agencies. We have quarterly meetings with the Maryland Department of the Environment where we share what we’ve been working on and what we’ve learned. The policy impacts our research has is very tangible, especially with ozone-based regulations. It satisfies my drive to help people. After I graduate, that aspect is something I really want to continue. I am heavily considering working with NOAA, EPA, NIST, or as a contractor for nonprofit environmental organizations. Most students in my program take the government agency route.