it as the Ice Age

Twenty thousand years ago,the Earth was a frigid landscape where woolly mammoths roamed.Huge ice sheets, several thousand meters thick,encased parts of North America, Asia, and Europe.We commonly know it as the Ice Age.But geologists call it the Last Glacial Maximum.That because it's the most recent time that ice reached such a huge extent,and ice age is an informal term without a single agreed-upon definition.Over the last million years,there have actually been about 10 different glacial maxima.