Tahoe, Tenaya, and Tioga, Sierra Nevada, USA In the Sierra Nevada , there are three named stages of glacial maxima (sometimes incorrectly called ice ages ) separated by warmer periods. These glacial maxima are called, from oldest to youngest, Tahoe , Tenaya , and Tioga .  The Tahoe reached its maximum extent perhaps about 70,000 years ago. Little is known about the Tenaya. The Tioga was the least severe and last of the Wisconsin Episode. It began about 30,000 years ago, reached its greatest advance 21,000 years ago, and ended about 10,000 years ago. Greenland glaciation In Northwest Greenland, ice coverage attained a very early maximum in the last glacial period around 114,000. After this early maximum, the ice coverage was similar to today until the end of the last glacial period. Towards the end glaciers readvanced once more before retreating to their present extent.  According to ice core data, the Greenland climate was dry during the last glacial period, precipitation reaching perhaps only 20% of today's value. 
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