Maximum Pleistocene Glacier Extents, Alaska PaleoGlacier Atlas
Manley W. 2002. Maximum Pleistocene Glacier Extents, Alaska PaleoGlacier Atlas. William Manley, Univ. of Colorado, INSTAAR
The Alaska PaleoGlacier Atlas is a geospatial summary of Pleistocene glaciation across Alaska. The layers in the atlas depict: 1) the extent of glaciers during the late Wisconsin glaciation (also known as the Last Glacial Maximum, about 20,000 years ago), and 2) the maximum extent reached during the last 3 million years by the northwestern Cordilleran Ice Sheet, ice caps, and valley glaciers. The atlas is targeted for a scale of 1 to 1,000,000 -- suitable for visualization and regional analyses. Former glacier extents are based on decades of field-based mapping, air-photo interpretation, and a variety of dating methods. In all, the first version combines glacial-geologic information from 26 publications and 42 source maps. Revisions will be made and released as time and resources allow. Pleistocene glaciers once covered >1,200,000 km2, from the continental shelf bordering the North Pacific to the northern foothills of the Brooks Range. Late Wisconsin glaciers occupied 727,800 km2 -- nearly ten times the area of modern glaciers, but only 48% of the state. Alaska's glaciers expanded more than 20 times during the last 3 million years in response to cold and snowy conditions. During the late Wisconsin glaciation, when sea level fell approximately 125 m (approx. 400 ft), the Bering Land Bridge was exposed as a broad tundra plain, and much of the state escaped glaciation due to a cold but dry climate. Deposition and erosion by glaciers in the recent geologic past have greatly influenced Alaska's landscapes and ecosystems.
- Type
- Geospatial Dataset
- Authors
- Manley, William F.
- Date of Issue
- 2002-08-08
- Publisher
- William Manley, Univ. of Colorado, INSTAAR
- Units
- AKRO , ANIA , BELA , CAKR , DENA , GAAR , GLBA , KATM , KEFJ , KLGO , KOVA , LACL , NOAT , SITK , WRST , YUCH
- Keywords
- Ahklun Mountains, AKRO, Alaska, Alaska Peninsula, Alaska Range, Alaska Region NPS Regional Office, Aleutian Range, Brooks Range, coastal ranges, Geology, Geoscientific Information, Glacial Geology, Glaciers, Kenai Mountains, Kodiak Island, Kuskokwim Mountains, Last Glacial Maximum, late Wisconsin, paleoenvironments, Pleistocene, Quaternary, Seward Peninsula, St. Elias Mountains, USA, Wrangell Mountains, Yukon Tanana Upland