Documenting a powerful interplay among climate change, the freeze-thaw dynamics of polygonal ground and the delivery of surface water by floods as well as snow and ice melting, the team developed a new view of the physical controls governing the speed and pattern of river channel development in these fragile landscapes.

"One of the key processes we identified in the evolution of stream networks is that their development is influenced by the way water flows through fields of roughly 10 meter-wide polygons, created through the freezing and thawing of the soil in Arctic regions," says Shawn Chartrand, assistant professor in the School of Environmental Science at Simon Fraser University, and lead author of research published in Nature Communications.

"This influence is also affected by the timing, magnitude and duration of flood events, as well as whether the underlying sediment particle substrates are frozen, or partially frozen."

Chartrand is part of an international research team that arrived at the uninhabited island of Axel Heiberg at the start of one of the most intense summer warming events ever recorded. Their field research focused on the island's Muskox Valley, east of the Muller Ice Cap. Researchers combined air photographs from 1959 with field observations and state-of-the-art Light Detection and Ranging (LiDAR) data they collected in 2019 to understand how the Axel Heiberg Island landscape has evolved over a 60-year period.