SciencePrehistoricGreenland/North Atlantichigh confidence

The warming that ended the Younger Dryas took only about 40–50 years, with Greenland ice-core samples showing temperature increases of up to 10°C (18°F) in just a few decades.

Notes on verification

Multiple independent peer-reviewed sources (Nature 1989, Quaternary Science Reviews 2022, arXiv 2010) and expert commentary corroborate rapid warming of ~7-10°C within a few decades at the end of the Younger Dryas, though exact magnitude/duration vary slightly across studies. [tier=gold indep_score=1.0 clusters=4 claim_tier=notable]

Sources