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

Researchers found physical evidence that the Laurentide Ice Sheet hit its smallest size about 3,600 years ago and began re-expanding roughly 2,000 years ago. That growth continued until about 1960, when human-caused warming reversed it.

• Laurentide Ice Sheet reached its minimum about 3,600 years ago
• Re-expansion of the ice began roughly 2,000 years ago
• About 70% of radiocarbon dates on moss cluster around 1800 CE
• Barnes Ice Cap margin has retreated 200–800 m since 1960