SciencePrehistoric (c. 12,900–11,700 years BP)North Atlantic / Northern Hemispherehigh confidence

During the Younger Dryas, an abrupt shutdown of thermohaline circulation in the North Atlantic was associated with an influx of large volumes of freshwater from melting glaciers.

Notes on verification

Widely supported leading hypothesis across multiple independent, high-quality sources (Britannica, PNAS, EBSCO, academic lecture materials); exact triggering/routing mechanism still debated but core claim is well corroborated. [tier=gold indep_score=0.95 clusters=3 claim_tier=notable]

Sources