Ice Age
Glacial period refers to a period of continuous global low temperature, where the continental ice sheet extends extensively to the equator, in an "ice age" (the time span is tens of millions or even two billion years). While the interglacial glaciation refers to the period between the two glaciers, the global temperature is higher, the mainland ice cover a substantial ablation of the period. The glacial and interglacial periods are hundreds of thousands of years. An ice age by the glacial period, interglacial alternating alternately. At present, the Earth is in the Quaternary ice age, 500,000 years there have been five ice age, each ice age lasted more than 70,000 years, and each ice age lasted an average of more than 20,000 years. It is the beginning of the interglacial period of 11,000 years ago, which is the beginning of the Holocene, and the period of alternating cold and warm in the ice age is called ice (or ice) Ice). The time scale is tens of thousands of years. ...