This striking satellite photo shows the point where a tiny lake bisects the snowy rim of a massive ancient glacier on a Canadian island in the Arctic Circle.

The small body of water, dubbed Gee Lake, is around 2 miles (3.2 kilometers) across at its widest point. It is located along the edge of the southeast limb of the Barnes Ice Cap — a roughly 2,300-square-mile (6,000 square kilometers), "bowling-pin-shaped" glacier situated at the center of Baffin Island in Canada's Nunavut territory.

In this image, captured in early September 2010, both the lake and the ice cap are still snow-free, except for the ice cap's edge, due to warmer summer temperatures. As a result, we can see the dark gray of the glacier, which is caused by the buildup of dust between layers of ice "spanning time periods that dwarf a human life," according to NASA's Earth Observatory. (In the winter, the glacier, lake and surrounding landscape are blanketed with snow.)

The exposed ice, which is up to 1,600 feet (500 meters) thick, is marked with striations that look like the "growth lines on a clamshell" running east to west, Earth Observatory representatives wrote.

These grooves are ridges cut by meltwater streams running off the glacier, Ted Scambos, a glaciologist at the University of Colorado Boulder and the National Snow and Ice Data Center, told the Earth Observatory. And while they give the impression that the ice is undulating, the surface of the glacier is surprisingly flat and smooth, he added.

Ice core samples collected from the glacier reveal that parts of the Barnes Ice Cap date back around 20,000 years, making it Canada's oldest known ice, according to a 2008 study. It is also the last remaining fragment of the Laurentide Ice Sheet, which covered most of Canada and the northern U.S. as far back as 100,000 years ago and helped to carve out the Great Lakes.

By around 20,000 years ago, as the last ice age began to thaw, most of the Laurentide Ice Sheet had melted away. But what was left slowly migrated north, toward what is now Baffin Island, where it eventually disappeared into the sea (aside from the Barnes Ice Cap). A 2009 study revealed that most of the melting ice passed through the Kangiqtualuk Uqquqti Fjord (previously known as the Sam Ford Fjord), around 70 miles (110 km) northeast of Gee Lake.

Although most of the Laurentide Ice Sheet is long gone, we can still see its impacts today. Recent research has shown that its meltwater has significantly altered ocean currents, while the geological "rebound" caused by the vanished weight that once pressed down on North America may be causing some major U.S. cities to sink and also affecting parts of Greenland.

Like most other glaciers in the Arctic and Antarctica, the Barnes Ice Cap is shrinking as a result of rising temperatures from human-caused climate change.

Although its current rate of ice loss is minimal — just a few meters of retreat per year — this will increase sharply as temperatures rise further. A 2017 study predicts that most of the glacier will "likely disappear in the next 300 years."

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Harry is a U.K.-based senior staff writer at Live Science. He studied marine biology at the University of Exeter before training to become a journalist. He covers a wide range of topics including space exploration, planetary science, space weather, climate change, animal behavior and paleontology. His recent work on the solar maximum won "best space submission" at the 2024 Aerospace Media Awards and was shortlisted in the "top scoop" category at the NCTJ Awards for Excellence in 2023. He also writes Live Science's weekly Earth from space series.