Canada’s sole remaining epishelf lake, characterized by freshwater floating on saltwater, has disappeared, along with the distinctive ecosystem it sustained, scientists have verified in a recent study. Jérémie Bonneau, an assistant professor at Laval University in Quebec City and the study’s lead author, expressed sorrow over the loss of the Milne Fiord epishelf lake on Ellesmere Island in Nunavut, which he described as the last of its kind in Canada. Bonneau emphasized the impact of the warming climate on the Arctic, highlighting the lake’s vanishing as a clear sign of environmental transformation.
Although prior reports had mentioned the demise of the lake, the latest study, published in Scientific Reports, provides a detailed account of the lake’s disappearance, referring to the irreversible loss as a significant shift marking the end of a 4000-year era. Researchers observed that the complete disappearance of this once-common phenomenon illustrates the Arctic’s changing landscape due to climate change.
Epishelf lakes form due to unique geological configurations, with the Milne Fiord lake being dammed by the Milne Ice Shelf for thousands of years, allowing freshwater to accumulate on top of the Arctic Ocean’s saltwater. The lake, hidden beneath a layer of ice year-round, was a distinct ecosystem with separate freshwater and saltwater communities living in close proximity. The lake’s collapse occurred in 2020 when the Milne Ice Shelf disintegrated, releasing the freshwater into the fiord, leading to the demise of its inhabitants.
The study’s findings shed light on the rapid drainage of the freshwater following the ice shelf’s collapse, demonstrating the swift transformation of the lake into a typical marine environment with seawater. While epishelf lakes have vanished from Canada, a few remain in Greenland and Antarctica, signaling the precarious future of these unique ecosystems as climate change continues to impact the planet.