Atlantic Mud Shows How Melting Ice Triggered an Ancient Chill

摘要

Eighty-two hundred years ago, a chill swept around the Northern Hemisphere, the last, feeble gasp of the mighty 100,000-year ice age that preceded it. Geologists looking for a cause had glimpsed evidence that a vast outpouring of glacial meltwater had gushed into the Atlantic Ocean less than a year after an ice dam busted. That meltwater outburst, seven times as voluminous as all five present-day Great Lakes, had come suspiciously close to the 8200-year, or "8K," chill. But paleoceanographers couldn't answer the big question: How could it have affected deep-sea currents believed to-play a pivotal role in controlling climate?