May 07, 2015

Earthquake Relief and Early Recovery in Nepal Count on Integrated Geo-Spatial Information

(7 May 2015, Geneva, Switzerland) On 25 April, Nepal was hit by a 7.8 magnitude earthquake. As of 6 May, the number of casualties is reported at 7,675 while 16,392 have been injured. Immediately after the red alert by the Global Disaster Alert and Coordination System (GDACS), UNICEF and OCHA requested UNOSAT rapid mapping service. Priority areas of interest were identified and UNOSAT began the acquisition of satellite imagery through the International Charter on Space and Major Disasters (Space Charter) and from commercial vendors.

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In large emergencies of this kind, as satellite imagery become available, several remote sensing entities start to assess the damage in various ways. Being able to integrate these various sources into a common platform is crucial for easy access to information in support of overall humanitarian coordination efforts. UNOSAT acts also as the GDACS coordinator for mapping products that can be useful in the emergency response phase. This role facilitates the integration of results from various sources by UNOSAT experts into a web-map that is made publicly available on-line. This GDACS LIVE map has several advantages and allows for very fast updates every time new information is available. The Nepal LiveMap currently includes

  • Status of areas being assessed using satellite imagery (planned, in progress or completed)
  • Consolidated and individual building damage assessments derived from satellite imagery analysis
  • Locations of landslides
  • Satellite imagery derived ground displacement
  • Ground photos from volunteers using the UN-ASIGN smartphone app that uploads photos in near real time onto the LIVE map

While carrying all this information the LIVE map allows for the overall view of the situation and also lets the user zoom in on specific thematic or geographic areas of interest. Data layers can be combined to illustrate for example the relationship between building damage assessments and ground displacement, as illustrated below. Here one can see the high correlation of building damage (points on the map) and people displacement (high displacement in red and yellow, lesser in purple and brown). The circles illustrate the distance from epicentre (20, 40 and 60 km respectively).

The GDACS LIVE web-map is also a good example of how photos from the disaster area taken by volunteers can acquire specific value when combined with satellite derived analysis. The UN-ASIGN smartphone app, developed by UNOSAT and Norwegian partner AnsuR Technologies, allows photos to be automatically geo-referenced and uploaded in near real time to UNOSAT’s server hosted at the European Organization for Nuclear Research (CERN) in Geneva. In some cases the photos are used to validate satellite imagery assessments and they may provide accurate details on damage in specific locations. The photo below is an example from Kathmandu taken on May 1st.

Both the regular print-ready maps showing UNOSAT’s own damage assessments derived from imagery, as well as the GDACS LIVE web-map, are being used to plan relief work and prioritize support for the most affected areas. The information is also used to identify specific affected villages and their status after the earthquake. As one user of this information said “I cannot emphasize enough how helpful these analyses have been.”

Using this integrated approach on-line allow for a comprehensive overview of a disaster in a much shorter time and also allows for planning early recovery more timely.

Currently, the UNOSAT LiveMap on Nepal combines data and information from

  • Space Charter
  • US Government (NGA, NASA)
  • European Commission Copernicus
  • Indian Space Research Organisation (ISRO)
  • Kongsberg Satellite Services
  • Digital Globe
  • Open Street Map community
  • European Space Agency (ESA)
  • AnsuR Technologies
  • UNITAR-UNOSAT

Other entities are welcome to contribute data to the consolidated damage assessment, as well as other relevant data.

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