nhess-18-185-2018.pdf (8.12 MB)
Satellite-based emergency mapping using optical imagery: experience and reflections from the 2015 Nepal earthquakes
journal contribution
posted on 2018-02-06, 14:28 authored by Jack G. Williams, Nick J. Rosser, Mark E. Kincey, Jessica Benjamin, Katie J. Oven, Alexander L. Densmore, David G. Milledge, Tom R. Robinson, Colm J. Jordan, Tom DijkstraTom DijkstraLandslides triggered by large earthquakes in mountainous regions contribute significantly to overall earthquake losses and pose a major secondary hazard that can persist for months or years. While scientific investigations of coseismic landsliding are increasingly common, there is no protocol for rapid (hours-to-days) humanitarian-facing landslide assessment and no published recognition of what is possible and what is useful to compile immediately after the event. Drawing on the 2015 Mw 7.8 Gorkha earthquake in Nepal, we consider how quickly a landslide assessment based upon manual satellite-based emergency mapping (SEM) can be realistically achieved and review the decisions taken by analysts to ascertain the timeliness and type of useful information that can be generated. We find that, at present, many forms of landslide assessment are too slow to generate relative to the speed of a humanitarian response, despite increasingly rapid access to high-quality imagery. Importantly, the value of information on landslides evolves rapidly as a disaster response develops, so identifying the purpose, timescales, and end users of a post-earthquake landslide assessment is essential to inform the approach taken. It is clear that discussions are needed on the form and timing of landslide assessments, and how best to present and share this information, before rather than after an earthquake strikes. In this paper, we share the lessons learned from the Gorkha earthquake, with the aim of informing the approach taken by scientists to understand the evolving landslide hazard in future events and the expectations of the humanitarian community involved in disaster response.
Funding
The research was funded by NERC Urgency Grant NE/N007689/1, the NERC-ESRC Earthquakes without Frontiers project (NE/J01995X/1), GCRF grant NE/P016014/1, and the UK Department for International Development (DFID) as part of the Science for Humanitarian Emergencies and Resilience (SHEAR) program. This study has also been in part supported by the DIFeREns2 (2014–2019) COFUND scheme supported by the European Union’s Seventh Framework Programme no. 609412).
History
School
- Architecture, Building and Civil Engineering
Published in
Natural Hazards and Earth System SciencesVolume
18Issue
1Pages
185 - 205Citation
WILLIAMS, J.G. ... et al, 2018. Satellite-based emergency mapping using optical imagery: experience and reflections from the 2015 Nepal earthquakes. Natural Hazards and Earth System Sciences, 18 (1), pp. 185-205.Publisher
Copernicus Publications on behalf of the European Geosciences Union © Author(s)Version
- VoR (Version of Record)
Publisher statement
This work is made available according to the conditions of the Creative Commons Attribution 4.0 International (CC BY 4.0) licence. Full details of this licence are available at: http://creativecommons.org/licenses/ by/4.0/Publication date
2018-01-16Notes
This is an Open Access Article. It is published by Copernicus Publications under the Creative Commons Attribution 4.0 International Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/. The middle initial for author Colm J. Jordan has been incorrectly identified in the paper as “A.”. The correct citation of Colm J. Jordan should be used to find other papers by this author.ISSN
1561-8633eISSN
1684-9981Publisher version
Language
- en