Younger Dryas Period Begins

Approximately 12,900 years ago, a sudden return to near-glacial conditions interrupted the warming trend following the Last Glacial Maximum. This period, lasting until roughly 11,700 years ago, saw temperatures over Greenland drop 4 to 10 degrees Celsius within decades. The prevailing scientific explanation attributes the cooling to a massive influx of glacial meltwater into the North Atlantic, disrupting the circulation that transports heat northward. The resulting cold and dry conditions across the Northern Hemisphere affected human populations and may have contributed to the transition from foraging to early agriculture in some regions.