Central Greenland was nearly 14 °C (24.5 °F) colder during the Younger Dryas than it is today.
Notes on verification
Confirmed by multiple independent sources including Severinghaus et al. (1998, Nature) and PNAS studies, with the 14-15°C figure widely cited for central Greenland (Summit/GISP2/GRIP sites); minor variability exists across studies depending on location and method. [cascade flags: wikipedia_dropped_other_sources_exist | tier=silver indep_score=1.0 clusters=2 claim_tier=notable]
Sources
- Younger Dryas | Definition, Causes, & Termination (seed:history_and_archaeology)
- https://www.pnas.org/doi/10.1073/pnas.1202183109 (corroboration)
- https://pure.psu.edu/en/publications/timing-of-abrupt-climate-change-at-the-end-of-the-younger-dryas-i/ (corroboration)