Landslides have uncovered the remnants of an ancient glacier on Bylot Island in the Canadian Arctic. Buried within the permafrost, researchers believe this is the oldest glacier ice ever found in the Arctic.
The glacier piece became visible after 2009 landslides in the area. Researchers were studying a fossil forest buried in the same hillside when they stumbled across the ancient ice.
Permafrost is a layer of ground that has been frozen for at least two years. This particular patch has been frozen considerably longer. As the world warms, the permafrost thaws, triggering landslides.
Scientists noticed layers of translucent ice in the debris of one slide. They decided to radiocarbon date some of the organic matter in the ice and discovered that it was over 60,000 years old.
“I was not expecting that at all,” said Daniel Fortier, co-author of the recent study.
Bylot Island, background, lies just north of Pond Inlet, the northernmost town on Baffin Island. Photo: Jerry Kobalenko
Intrigued, they started testing the layers of sediment on top of the ice. Within the soil, there was evidence of a flip in the alignment of magnetic materials approximately 770,000 years ago. This lines up perfectly with a known reversal of the planet’s magnetic field around that time.
A time capsule
Though the exact age of the glacier is unknown, it falls between 770,000 years and 2.4 million years, the age of the fossil forest that lay below the ice. At that time, the High Arctic was merely subarctic. Trees grew, and beavers lived there.
Encased in this ancient ice are gas bubbles, compounds, dust, and other material. It is a time capsule giving a window into the climate of the early Pleistocene.
The glacier dates from a time of cyclical ice ages and warm interglacials. Scientists hope to measure how the various greenhouse gases have varied within these cycles and decipher how they affected past climates.
Similarly, the dust and rocks may hold information about ancient volcanic eruptions and how these link to changing conditions. Now the race is on to unlock all of the information the glacier holds before it melts away and its treasures are lost.
