Younger Dryas impact hypothesis

Articles relating to the Younger Dryas impact hypothesis and its depictions. It is a speculative attempt to explain the onset of the Younger Dryas (YD) as an alternative to the long-standing and widely accepted cause due to a significant reduction or shutdown of the North Atlantic "Conveyor" in response to a sudden influx of freshwater from Lake Agassiz and deglaciation in North America. The YDIH posits that fragments of a large (more than 4 kilometers in diameter), disintegrating asteroid or comet struck North America, South America, Europe, and Western Asia around 12,850 years ago, coinciding with the beginning of the Younger Dryas cooling event. Advocates proposed the existence of a Younger Dryas boundary (YDB) layer that can be identified by materials they interpret as evidence of multiple meteor air bursts and/or impacts across a large fraction of Earth’s surface.