5 October 2017

Hurricane Maria: USGS landslide impact maps from Puerto Rico reveal the extent of the devastation

Posted by Dave Petley

Hurricane Maria: USGS landslide impact maps from Puerto Rico reveal the extent of the devastation

From across the Atlantic, the response of the White House to the Hurricane Maria disaster in Puerto Rico looks astonishing.  With little fanfare, the USGS has now started to release maps of the impacts of landslides triggered by the hurricane, created through the analysis of satellite imagery.  USGS staff are past masters at this sort of mapping, which is both challenging and time-consuming.  They have released the first tranche of data, for a part of northwest Puerto Rico:-

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It is important to note that this not a landslide map, it is a map of the impacts of landslides – i.e. the locations in which a landslide has affected a road, a building or another element of infrastructure.  This is illustrated by one of the images that the USGS has released alongside the map:-

Hurricane Maria

Digital Globe image of the imoacts of landslides triggered by Hurricane Maria in Puerto Rico. The red dots are the mapped impacts on humans,

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There are eight mapped impacts (the red dots) on this image, but far more landslides.  Another example of the extent and impact of this event is this image, from the San Antonio Express-News, that shows multiple landslides and extremely high levels of damage in the upland areas of Puerto Rico:-

Hurricane Maria

Image from the San Antonio Express-News showing landslide damage from Hurricane Maria in Puerto Rico

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The Washington Post has published a rainfall map for Hurricane Maria in Puerto Rico:-

Hurricane Maria

Map of the rainfall deposited on Puerto Rico for Hurricane Maria. Map by the Washington Post

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This suggests that the mapped area had some of the higher levels of rainfall, but this amount is replicated across much of the rest of the island.  In turn, this suggests that similar levels of landslide damage are likely elsewhere.