Arctic Snow Leads Students to Chemistry
Photo above: UM undergraduates Alicia Kevelin and Claire Mattson worked closely with Chemistry future faculty graduate student instructor and Pratt Lab member Nate May (as well as a local Ukpeaġvik Iñupiat Corporation-Science guard to keep a lookout for polar bears) to collect snow samples for analysis in the Authentic Research Experience in Snow Chemistry Chem 125/26 Lab this fall. Photo courtesy of Pratt Lab.
Trading in their lab coats for expedition quality parkas, UM first year students Alicia Kevelin and Claire Mattson set off on snowmobiles across the frozen tundra and sea ice around Barrow, Alaska last March. It was a most unusual spring break in the service of an introductory chemistry laboratory course.
In the Fall 2015 semester, Kevelin and Mattson were students in Dr. Kerri Pratt’s “Authentic Research Connection” section of the introductory lab, Chem 125/26. Pratt is an assistant professor in the Department of Chemistry participating in an education innovation to develop an exploratory laboratory courses—akin to how science is actually done rather than using “cookbook” exercises.
An environmental analytical chemist, Pratt’s own research explores the chemical interactions between atmospheric trace gases, particles, clouds, snow and the frozen sea ice to understand processes associated with air quality and climate change.
She hoped to convey to these novice chemists the excitement of teasing apart the unique chemistry that exists in the Arctic snowpack.
Through the weeks of the class, students did exercises that gave them the expected training in chemistry methods and approaches. For example, students were exposed to general chemistry topics such as solutions and dilutions through lab sessions where they prepared calibration standards for ion chromatography. To learn redox reactions and absorbance spectroscopy, they synthesized and quantified Cl2 used to calibrate the gas phase instruments. Rather than each lab session standing alone, the series of techniques built on each other, resulting in a wealth of data for analysis that the students turned into manuscripts and scientific posters. In lieu of the final exam, students gave poster presentations just as scientists typically do at professional meetings. Pratt rounded up faculty, postdocs, and graduate students to judge the poster session. “The presentations were so well done that the judges were amazed that these were novice chemistry students. Some judges even thought the presenters were graduate students!” says Pratt.
In the Arctic this spring, Kevelin and Mattson collected the samples and hauled them back to Ann Arbor in four thick walled coolers. The Fall 2016 students are now analyzing those samples. According to Kevelin,“In all, we collected just under 100 snow samples! …the students have a boatload of knowledge to gain from these sample analyses.” The samples came from the edge of the Elson Lagoon, actual sea ice, and tundra. “Students will clearly be able to see the changing snow chemistry and factors that influence it.”
Kevelin, in particular, was excited to analyze the samples using ion chromatography. “I have seen countless chloride, bromide, and sodium concentrations, numerous pH readings, and too many ion ratios to count, but I have never gotten to be on the other side—to reap the benefits of my own hard labor, essentially going from start to finish, connecting all the dots.
“This is the closest I have ever gotten to making a real impact, and the feeling is much more exhilarating than I could have ever imagined…As I am finally getting to make my mark on the world, this trip has sure made its mark on me.”
The trip was made possible by funding from the Howard Hughes Medical Institute, UM Department of Chemistry, UM Program in the Environment, UM Program in International & Comparative Studies (via Arctic Internships to Kevelin and Mattson), and the National Science Foundation.
Snow Chemistry is one of two introductory chemistry labs in the ARC program. The other section explores what it takes to make a functional solar cell. That class is led by Associate Professor Stephen Maldonado.