'Warm Blob' Caused Wild Climate Swings During Last Ice Age

A "warm blob" of surface water played a role in Greenland's wild climate swings during the last ice age, a new study finds. Greenland's climate flipped quickly and brutally from cold to warm and back again 25 times between about 20,000 and 70,000 years ago, ice cores and ocean sediments show. The abrupt climate swings, called Dansgaard-Oeschger events, involved extreme changes in average temperature.