Canada’s sole remaining epishelf lake, characterized by freshwater floating on saltwater, has vanished, along with the distinct ecosystem it sustained, as confirmed by scientists in a recent study. The lead author, Jérémie Bonneau, an assistant professor at Laval University in Quebec City, expressed sorrow over the disappearance of the Milne Fiord epishelf lake on Ellesmere Island in Nunavut, emphasizing its uniqueness in Canada.
The study, recently published in the journal Scientific Reports, elaborates on the process leading to the lake’s demise and emphasizes the irreversible loss as a significant consequence of climate change in the Arctic region. The disappearance of this phenomenon, present for over 4,000 years, underlines the impact of a warming climate on transforming Arctic landscapes.
Epishelf lakes, formed by glaciers damming freshwater from flowing into the ocean, create a unique environment where freshwater accumulates on top of denser saltwater due to the glacier blocking its release. The Milne Fiord epishelf lake, which had a freshwater layer 18 meters deep in 1983, showcased a distinct ecosystem with separate communities in the freshwater and saltwater layers.
The lake’s collapse in 2020, following the fragmentation of the Milne Ice Shelf on Ellesmere Island, led to the instantaneous mixing of freshwater with seawater, resulting in the loss of the lake’s inhabitants. The disappearance of this epishelf lake marks the end of a rare Arctic ecosystem, highlighting the ongoing impact of climate change on unique natural environments.
While epishelf lakes are no longer present in Canada, a few still exist in Greenland and Antarctica, though their future is uncertain. Scientists emphasize the importance of protecting such ecosystems as they face the threat of extinction due to environmental changes.
