The Younger Dryas period lasted approximately 1,300 years and consisted of freezing temperatures.
Notes on verification
Corroborated by Britannica, a peer-reviewed PNAS paper, and UCAR, all citing the ~1,300-year duration and cold conditions, though a few marine-record studies suggest slightly shorter durations. [cascade flags: aggregator_dropped_primary_exists | tier=silver indep_score=1.0 clusters=2 claim_tier=notable]
Sources
- News - What Caused the Deep Freeze of the Younger Dryas? - Archaeology Magazine (seed:history_and_archaeology)
- https://www.pnas.org/doi/10.1073/pnas.2007869117 (corroboration)
- https://scied.ucar.edu/learning-zone/how-climate-works/big-freeze-rapid-cooling-during-younger-dryas (corroboration)