Thanks to their use of a unique methodology, a McGill-led research team has obtained new insights into how boulders affect snow melt in mountainous northern environments, with implications for local water resources.
The team found that snow near boulders melts faster, not only because rocks radiate heat, but also due to subtle processes that reshape the snow's surface. This information will help researchers understand how small-scale processes affect downstream water resources.
"It's not surprising that snow melts faster near boulders," said principal investigator Eole Valence, a PhD student. "But we were able to measure it directly and gather the data to show how it happens."
Data down to the centimetre
Most snow hydrology research is done at a watershed scale or with coarse satellite observations. However, this study, conducted in the Yukon's Shár Shaw Tagà Valley, measured snow depth and melt patterns within just a few centimetres of each boulder.
The study is the first to track the phenomenon in a remote environment at such a fine resolution. The researchers used a unique methodology combining 3D environmental laser scans (LiDAR), infrared cameras that measure the snow's surface temperature, and drone photogrammetry, which uses photography to create a digital elevation model.
"There are some amazing new tools for observation that have not yet been applied in remote settings due to logistics. It's a new tier of observational data collection in remote environments," said Jeffrey McKenzie, co-author and Professor in the Department of Earth and Planetary Sciences.
The researchers said this methodology provides a crucial missing link between what satellites can observe and what actually happens on the ground as snow and ice melt, helping connect local processes to large-scale climate models.
