An Earth history of sudden global climate changes. What the scientists found was surprising and unnerving. They had known from previous ice core and ocean sediment core data that Earth’s climate had fluctuated significantly in the past. But what astonished them was the rapidity with which these changes occurred. Ocean and lake sediment data from places such as California, Venezuela, and Antarctica have confirmed that these sudden climate changes affected not just Greenland, but the entire world. During the past 110,000 years, there have been at least 20 such abrupt climate changes. Only one period of stable...







