Landslides occur when an environmental trigger like an extreme rain event, often a severe storm or hurricane, and gravity's downward pull sets soil and rock in motion. Conditions beneath the surface are often unstable already, so the heavy rains act as the last straw that causes mud, rocks, or debris- or all combined- to move rapidly down mountains and hillsides. Unfortunately, people and property are often swept up in these unexpected mass movements. Landslides can also be caused by earthquakes, surface freezing and thawing, ice melt, the collapse of groundwater reservoirs, volcanic eruptions, and erosion at the base of a slope from th flow of river or ocean water. But torrential rains most commonly activate landslides. The NASA Global Landslide Catalog (GLC) was developed with the goal of identifying rainfall-triggered landslide events around the world, regardless of size, impact, or location. The GLC considers all types of mass movements triggered by rainfall, which have been reported in the media, disaster databases, scientific reports, or other sources. THe GLC has been compiled since 2007 at NASA Goddard Space Flight Center. Landslide inventories are critical to support investigations of where and when landslides have happened and may occur in the future; however, there is surprisingly little information on the historical occurrence of landslides at the global scale. This visualization displays all rainfall-triggered landslides from 2007 through December 2015 from a publically available global rainfall-triggered landslide catalog(GLC). This is a valuable database for characterizing global patterns of landslide occurence and evaluating relationshipswith extreme precipitation at regional and global scales. For more information on the Global Landslide Catalog, please visit http://ift.tt/1PT1MwV
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