AN INTERACTIVE NATIONAL-SCALE MAP OF LANDSLIDE OCCURRENCE ACROSS THE UNITED STATES

Recently we gathered and combined many geodatabases of landslide occurrence across the United States as a step towards a national-scale landslide inventory. These data are presented in the form of a searchable online map, with common attributes and ready access to the original data sources. This map of landslide inventories represents a broad-based effort with contributions from many local, state, and federal agencies. Data confidence level has been scored numerically and is displayed visually. Thus, the map highlights the regions where high-confidence mapping is available to provide detailed information about landslide occurrence, which is needed to develop effective tools for landslide risk reduction and to advance process understanding. The map also shows where high-confidence mapping could further improve landslide characterization. This new compilation is preliminary and known to be incomplete across many parts of the country. For example, many contributed inventories are biased towards landslides that caused damage to transportation and infrastructure. Absence or sparseness of mapped landslides in areas of moderate to high relief identifies likely areas of incomplete landslide characterization where further mapping is warranted. Despite its incompleteness, the mapped spatial pattern and density of landslides is consistent with previous mapping of landslide potential at the national scale. Planned periodic updates of the database as new or improved landslide data become available will maintain and increase its usefulness in coming years. The database provides a starting point for one-stop access to information about landslide occurrence for land managers, emergency planners, researchers, and the public.

Please contact gs-haz_landslides_inventory@usgs.gov for more information on how to contribute inventories to this community effort.