THE PALEOGLACIER INVENTORY: A GEOSPATIAL DATABASE OF LATE-PLEISTOCENE MOUNTAIN GLACIATION FOR THE CONTERMINOUS WESTERN UNITED STATES

Pleistocene glaciations in North America featured glacier systems in numerous mountains of western North America. Decades of mapping glacial sediments and landforms have afforded reconstructions of mountain glacier shapes, chiefly during the last Pleistocene glaciation and subsequent deglaciation. The availability and scale of mapping and paleoglacier reconstructions varies across the region, however, and many areas with new mapping, Earth-surface imagery, and digital terrain models represent opportunities for updating existing map resources and ice reconstructions. We present updates to the PaleoGlacier Inventory, a geospatial database of digitized mountain glacier extents compiled from numerous studies across the region and designed for use in geographic information systems. The database features paleoglacier outlines as polygons drawn at scales ranging from 1:24,000 to 1:100,000, reflecting differences in available mapping resolution and degrees of confidence in the interpretation of mapped glacial features. The database allows users to visualize mountain paleoglacier outlines in the western U.S. and is available in a variety of formats to permit uses for research, education, and outreach activities. We present key updates to the database, including (1) addition of generalized outlines to permit visualization over larger areas, (2) a set of attributes designed to enable analysis of glaciation patterns, and (3) development of a web experience to permit viewing without a geographic information system. Additionally, we highlight areas where new outlines have been added or are in progress, emphasize the need for community contributions and input on the design of the database, and present examples of research applications involving the database.