There’s an ideal way to learn about retreating glaciers: visit them for the day.
That’s exactly what a group of UW students did in September 2021, when they hiked up to one of Mount Baker’s most prominent glaciers, Easton Glacier, and learned how to gather highly precise data that can be used to track glacier change.
“It’s a great educational opportunity — students just need a pair of hiking boots,” says CEE Assistant Professor David Shean. “There are things you experience when you are standing next to a glacier that you just can’t learn in a classroom. Students feel the wind and hear the roar of the waterfall as the glacier melts. They realize there are daily variations in these things, and you don’t get that from a textbook or PowerPoint slides.”
About twice per year, Shean takes students out to the glacier. Many have already taken or are planning to take Shean’s Advanced Surveying class, which covers modern surveying techniques for scientific and engineering applications.
“To go through the calculations and match up the elevation models and see clearly where the glacier has thinned was interesting,” says CEE Ph.D. student Seth Vanderwilt. “Just from standing on the hiking trail, if you took a picture every year, you would struggle to put a number on how much ice has melted away.”
The outings are a mix of teaching opportunity and research for Shean, who has been studying the glacier, located in the North Cascades, since 2014. During his Ph.D. studies, Shean started using satellite data to track glaciers in Washington and continues to monitor glacial change. In the past seven years, Shean has observed hundreds of meters of retreat and up to 20 meters of thinning in places.
“It’s important to monitor sites like Easton to understand the impacts of regional climate change, but coupled with that are changes in the snowpack, vegetation and surrounding landscape, such as bedrock that was covered with ice for thousands of years,” Shean says. “We are building a record that can be used to study this interconnected system in detail.”
Creating 3D models
Gathering highly precise data is just the first step. In Shean’s Advanced Surveying course, students learn to use software to stitch the drone images together and create 3D models and topographic maps.
For the final class deliverable, students apply what they’ve learned to a project of their choice. Teaming up with classmates, Vanderwilt processed the images gathered at Easton Glacier in September, along with all of the data going back to 2014. The students created a time series analysis with a combined 6,500 drone images, which revealed approximately 3-4 meters of thinning over the lower glacier each year.
For Besso’s final project, she worked with classmates to collect new drone imagery at the site of the 2014 Oso landslide, which they used to create data visualizations. Comparing their 3D models to post-landslide data gathered by the United States Geological Survey, the students found that in the aftermath of the landslide, the banks of the North Fork of the Stillaguamish River were eroding and the channel was widening.
“We took the project from the idea phase to going out to the field site to fly drones on a weekend,” Besso says. “It was something that was within our ability level after taking the class, but it took some training and planning because there were tall trees and challenging terrain and we didn’t want to crash the drones.”