St. Olaf researchers study snow for clues on climate change
For a team of St. Olaf College researchers, snow is more than a picturesque feature of their Minnesota campus — it’s a key to better understanding and predicting climate change.
“As the planet warms, we see a loss in snow and ice cover, which reduces the albedo — the proportion of energy reflected off a surface — of the planet as a whole, resulting in the planet absorbing more energy, leading to further warming, further ice loss, more energy absorbed — it’s a positive feedback loop that is negatively impacting the environment,” says student researcher Wesley Brown ’19.
As the planet warms, we see a loss in snow and ice cover, which reduces the albedo — the proportion of energy reflected off a surface — of the planet as a whole, resulting in the planet absorbing more energy, leading to further warming, further ice loss, more energy absorbed.Wesley Brown ’19
Under the guidance of St. Olaf Assistant Professor of Physics Alden Adolph, Brown and Karina Zikan ’20 have spent months researching snow properties and their relationship to the energy budget of snow-covered regions on both local and global scales. They presented their work this December at the American Geophysical Union Fall Meeting in Washington, D.C., where they had the opportunity to engage with scientists from around the world.
“It was very incredible and inspiring to be under the same roof as so many earth scientists all sharing their research,” says Zikan.
The science of snow
Zikan and Brown’s work began this summer as part of the college’s Collaborative Undergraduate Research and Inquiry (CURI) program, which provides opportunities for St. Olaf students from all academic disciplines to gain an in-depth understanding of a particular subject by working closely with a St. Olaf faculty member in a research framework.
Through multiple projects led by Adolph, they hope their findings may be able to provide more accurate predictions on climate change.
“When exposed to different temperature conditions, the structure of the snow evolves and changes,” Zikan says. “We’re working to create a system that will allow us to control both the top and bottom temperatures of a snow sample, and then we will look at how the albedo and grain structure of that snow sample changes.” This portion of the project will allow for improved modeling of snowpack changes within climate models on the local scale.
Utilizing temperature data from automatic weather stations in Greenland, installed and maintained by the Danish Programme for Monitoring of the Greenland Ice Sheet, Brown and Zikan have worked to validate remotely sensed temperature data gathered by a pair of satellites operated by NASA. This could inform potential changes to the algorithms and mechanisms in satellite-based measurements that would lead to more accurate quantification of how quickly this global positive feedback is snowballing.
With support from the Adam S. Thomas Science Endowment, Brown and Zikan worked throughout the fall to continue their studies of snow temperature in Greenland. Their presentations in Washington, D.C., focused on what they had learned from the Greenland data.
“I received a lot of positive feedback and encouragement from individuals who came to my poster after they found out that I was an undergraduate student,” Brown says. “It reinforced my decision to pursue a career in academia and allowed me to see how scientists at various points in their academic careers are able to communicate their findings to the broader scientific community.”
As they return to campus for second semester, Zikan and Brown will resume their work. They’ll be aided by half a foot of snow cover that has accumulated in the last month, as well as new research team members — Kavya Devgun ’21, Elvis Haisa ’21, and Isaiah Scharen ’20 — who will study snow physics as part of a Directed Undergraduate Research (DUR) course with Adolph.
“One of the things we will focus on this winter is a study of the snow in the St. Olaf Natural Lands,” Adolph says. The college’s 350 acres of Natural Lands not only serve as a hands-on learning laboratory for students, but also play an important role in conservation efforts led by a variety of academic departments on campus. “We will maintain a study site that we visit several times a week to chart the evolution of the snowpack throughout the winter, with a particular focus on the snow albedo.”
Research team members will measure a number of parameters including snow depth, snow grain size, and snow temperature. They’re also setting up a weather station nearby so they can monitor air temperature, humidity, pressure, and other relevant meteorological parameters.
“This work will help us to quantify the factors that control changes in snow albedo,” Adolph says. “Differences in how much light is absorbed affect how the temperature of the snow changes — just like how wearing a dark or light colored T-shirt affects your body temperature on a sunny day.”
Student researchers will also work with St. Olaf Instructional Technologists to use one of the college’s drones to make maps of snow depth at areas around campus. They will then investigate how snowmelt rates change as a function of the underlying topography or vegetation.
With all of this work, Adolph hopes that student researchers will not only compile compelling data, but will gain invaluable hands-on research experience.
“We’re really building our lab from the ground up: designing the systems we’re going to be using, figuring out what parts we need, and how to program our instrumentation,” Adolph says. “Having undergraduate students who are smart, passionate, interested in the subject matter, and eager to build their skill set has been really helpful to me in my first two years at St. Olaf. I’m grateful to have such bright students working with me.”