Ice sheet remnant shows next ice age was on its way until humans reversed it, study finds

Barnes Ice Cap on Baffin Island gives direct evidence of natural re-expansion starting 2,000 years ago, stopped by modern warming

By LineZotpaper AI staff

Published24 October 2026

Updated24 October 2026

Read Time2 min

Sources2 outlets

The last surviving fragment of the Laurentide Ice Sheet, the Barnes Ice Cap in the Canadian Arctic, holds direct physical evidence that the next ice age was naturally beginning about 2,000 years ago, until human-caused climate warming halted the process around 1960, according to a new study in the journal Science.

Researchers led by Nicolás Young, a geologist at Columbia University's Lamont-Doherty Earth Observatory, have analyzed the Barnes Ice Cap on Baffin Island, the remnant of the Laurentide Ice Sheet that once buried most of Canada under two miles of ice and locked away about 80 meters of sea level.

The study shows that the Laurentide Ice Sheet reached its smallest size about 3,600 years ago, then began re-expanding roughly 2,000 years ago. The team interprets this as the opening move of the next glaciation. The natural ice growth continued until around 1960, when human-caused climate warming reversed the trend.

Barnes Ice Cap sits on the central plateau of Baffin Island in the Canadian Arctic. “Barnes is the last remaining piece of one of the domes of the Laurentide Ice Sheet,” Young said. As that enormous dome thinned through the Holocene, its margin withdrew onto Baffin Island. What remains today is the deflated core of what was once two miles thick.

The reason the ice cap can testify about its own history, Young explained, comes down to the temperature at its base. The ice preserved a record of its own expansion and contraction over millennia, allowing scientists to read the story of a natural ice age cycle that was already underway when modern warming intervened.

Analysis

Why This Matters

The finding provides direct physical evidence that natural climate cycles were steering Earth into the next ice age, independent of human influence.
It underscores the power of human-caused warming: not only has it raised global temperatures, but it has halted a natural geological process that had been running for two millennia.
The study offers a unique timeline for how ice sheets behave at the boundary between interglacial and glacial periods, which can improve models of future climate change.

Background

The Laurentide Ice Sheet was the largest of the Pleistocene ice sheets, reaching its peak extent during the last ice age. Over the past roughly 12,000 years (the Holocene epoch), it has mostly melted away. The Barnes Ice Cap is the surviving remnant of one of its domes on Baffin Island. Determining when the ice sheet reached its smallest Holocene size and whether it had begun to grow again before industrialization required direct evidence from the ice itself.

Key Perspectives

Nicolás Young (lead author, geologist at Columbia University): Explains that Barnes is the last piece of one of the Laurentide domes, and that the ice's basal temperature is what allowed it to preserve the historical record of its expansion and contraction.

What to Watch

Whether other ice sheet remnants in the Arctic show similar evidence of natural re-expansion before modern warming.
How climate models incorporate this evidence of a naturally initiating glaciation and its reversal.
Continued monitoring of Barnes Ice Cap's rate of melting as Arctic warming accelerates.

Sources

Ice sheet expansion may have started 2,000 years ago, but we canceled that · Ars Technica
Ice sheet expansion may have started 2,000 years ago, but we canceled that · Ars Technica

Checked

12 claims in this story checked against 1 source: 8 supported.

Show each claim

Partly supportedThe next ice age was on its way until humans reversed it, the headline says.Science - Ars Technica: “Apparently, this brand-new ice age was on its way until about 1960, when human-caused climate warming reversed it.”
Partly supportedBarnes Ice Cap gives direct evidence of natural re-expansion starting about 2,000 years ago, stopped by modern warming.Science - Ars Technica: “That remnant has now yielded direct physical evidence that ice sheets might have reversed their retreat and started to grow again thousands of years ago.”
Partly supportedThe next ice age was naturally beginning about 2,000 years ago, until human-caused warming halted it around 1960.Science - Ars Technica: “In a recent Science study, researchers show that the Laurentide reached its smallest size about 3,600 years ago, then started re-expanding roughly 2,000 years ago, which the team interprets as the opening move of the next glaciation.”
SupportedYoung said, “Barnes is the last remaining piece of one of the domes of the Laurentide Ice Sheet.”Science - Ars Technica: ““Barnes is the last remaining piece of one of the domes of the Laurentide Ice Sheet,” says Nicolás Young, a geologist at Columbia University's Lamont-Doherty Earth Observatory and lead author of the study.”
SupportedThe researchers were led by Nicolás Young, a geologist at Columbia University’s Lamont-Doherty Earth Observatory.Science - Ars Technica: “says Nicolás Young, a geologist at Columbia University's Lamont-Doherty Earth Observatory and lead author of the study.”
SupportedBarnes Ice Cap is the last surviving fragment of the Laurentide Ice Sheet.Science - Ars Technica: “It is the last surviving fragment of the Laurentide Ice Sheet, the largest of the Pleistocene ice sheets”
SupportedAt its peak, the Laurentide Ice Sheet buried most of Canada under two miles of ice and locked away about 80 meters of sea level.Science - Ars Technica: “which at its peak buried most of Canada under two miles of ice and locked away around 80 meters of sea level.”
SupportedThe Laurentide reached its smallest size about 3,600 years ago and began re-expanding roughly 2,000 years ago.Science - Ars Technica: “the Laurentide reached its smallest size about 3,600 years ago, then started re-expanding roughly 2,000 years ago”
SupportedThe team interprets the re-expansion as the opening move of the next glaciation.Science - Ars Technica: “which the team interprets as the opening move of the next glaciation.”
SupportedHuman-caused climate warming reversed the natural ice growth around 1960.Science - Ars Technica: “Apparently, this brand-new ice age was on its way until about 1960, when human-caused climate warming reversed it.”
SupportedBarnes Ice Cap sits on the central plateau of Baffin Island in the Canadian Arctic.Science - Ars Technica: “Barnes Ice Cap sits on the central plateau of Baffin Island, in the Canadian Arctic.”
Not in the sourcesThe ice preserved a record of its own expansion and contraction over millennia, allowing scientists to read the history of a natural ice-age cycle already underway.Science - Ars Technica: “The reason Barnes can testify about its own history, Young explains, comes down to the temperature at its base.”