SciencePrehistoricGreenlandhigh confidence

Climate records preserved in Greenlandic ice show that Earth's last ice age included about 25 periods of abrupt climate change.

Notes on verification

Consistently corroborated by NOAA, peer-reviewed literature (Nature Communications, ScienceDirect), and academic research summaries (TiPES/University of Copenhagen), all confirming ~25 Dansgaard-Oeschger abrupt climate events during the last glacial period.

Sources