1 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 THE JANUARY 12, 2010 HAITI EARTHQUAKE:
A COMPREHENSIVE DAMAGE ASSESSMENT USING VERY HIGH
RESOLUTION AREAL IMAGERY
By
1
2
Ronald T. Eguchi , Stuart P. Gill , Shubharoop Ghosh1, Walter Svekla1,
Beverley J. Adams 3 , Galen Evans1, Joaquin Toro1, Keiko Saito 4 , and Robin Spence4
Background
This paper provides a brief account of how technology, inspiration and collaboration
were used to quickly assess the amount of damage caused by the January 12, 2010 Haiti
earthquake. In less than a minute, this event leveled approximately 20 percent of the buildings in
greater Port-au-Prince; killed close to a quarter of a million people; injured as many; and left
over a million individuals homeless. While not considered a great earthquake (from
seismological standards), this event will rank as one of the deadliest earthquakes of the 21st
century.
This event will also be known as one of the first events where technology (especially
high-resolution imagery) was embraced at such a large scale in a real operational sense. Almost
from the very onset of the disaster, high-resolution satellite imagery was available to provide the
first glimpse of the devastation caused by this earthquake. Days later, very-high resolution aerial
imagery was available to provide even more detail on the damage caused in this event. Together,
these valuable datasets allowed a small army of remote sensing experts to provide one of the
most accurate assessments of building damage in the last decade. Furthermore, this information
was shared with Haitian government officials in relatively short time – within two months of the
earthquake – in the form of a Building Damage Assessment Report in support of the PostDisaster Needs Assessment (PDNA) and Recovery Framework.
This paper discusses how three key international organizations – the World Bank (WB),
the United Nation Institute for Training and Research (UNITAR) Operational Satellite
Applications Programme (UNOSAT) and the European Commission’s Joint Research Centre
(JRC) – worked together, in the framework of the joint declaration signed in 2008 between the
World Bank, European Commission and the United Nations Development Group on post-crisis
Assessments and Recovery Planning, to produce this rapid assessment of building damage and
how these organizations are continuing this collaboration to improve response protocols for
future disasters. It is clear from the Haiti experience that the future of post-disaster damage
assessments has changed dramatically and that the “bar has been raised” for the next event. The
main purpose of this chapter is to document key lessons from the Haiti experience and to
recommend improvements that can be implemented by future responders.
Damage Assessment
The main outcome from the joint collaboration was the damage assessment. Damage
was measured by the number of buildings in different damage states. For ease of use, the joint
team agreed to use a damage scale that was developed several years ago in Europe – the
1
ImageCat, Inc., 400 Oceangate, Suite 1050, Long Beach, CA 90802, USA The World Bank, 1818 H Street, NW, Washington DC 20433, USA 3
ImageCat Ltd., Woodfield Lane, Suite G, Ashstead, Surrey, KT21 2BT, UK 4
Cambridge Architectural Research Ltd., 25 Gwydir Street #6, Cambridge, CB1 2LG 2
2 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 European Macroseismic Scale – 1998 version i . Fundamentally, this was one of the most
important decisions made by the WB-UNOSAT-JRC team because it ensured a common basis
for measuring the effects of the earthquake. By agreeing to use this scale, the damage
assessment results from each organization could be combined without significant re-adjustment.
Table 1 shows the damage totals for the ten communes that were significantly affected by
the earthquake. In total, over 90,000 buildings were either destroyed or experienced heavy
damage. This represents slightly less than one third of the building inventory in the affected
areas. Most of the damage occurred in Port-au-Prince; however, significant numbers of
buildings were also destroyed in Carrefour, Delmas, Leogane and Petion-Ville. Based on
median floor area estimates for different occupancy uses, this damage translates roughly to over
26 million square meters in building area affected with about one third of this total associated
with buildings that will have to be either replaced or significantly repaired. The total repair cost
to buildings is estimated to be over $6 billion (US).
Table 1. Number of Buildings Grouped by EMS-98 Damage Grade and Commune
EMS-981 Damage Grades
COMMUNE
5
4
3
2
1
Carrefour
2763
5905
5920
3220
35219
Cite Soleil
1012
549
1073
576
6403
Delmas
5012
2814
5064
2881
29478
Grand-Goave
148
541
421
276
2175
Gressier
565
289
567
319
3436
Jacmel
214
1785
1489
857
8799
Leogane
2220
5985
4139
2360
24736
Petion-Ville
2027
906
1693
708
10614
Petit-Goave
173
104
167
116
770
Port-Au-Prince
9902
15257
12351
6699
62693
Tabarre
532
365
663
383
3914
Total
24062
34500
33546
18395
188236
Note: 1-EMS-98: European Macro-seismic Scale (1998)
Significant Breakthroughs
Years from now, many of the details of the joint WB-UNOSAT-JRC Haiti response will
be forgotten; however, there are a number of outcomes that will remain a legacy of this
monumental effort. What was accomplished during the Haiti campaign changed the landscape
of global disaster response forever. The sheer magnitude of the event and its impact on the
country of Haiti and its people required a new paradigm of data collection and damage
assessment. Some of the notable accomplishments include:
ƒ PDNA damage assessment based primarily on the use of remote sensing technologies,
ƒ Crowd-sourcing technology as a means of mobilizing the expertise and passion of
hundreds of volunteers around the world to rapidly assess the level of building
destruction in greater Port-au-Prince, and
ƒ A myriad of geo-spatial products that helped to chronicle the relief efforts of tens of
volunteer organizations over time.
3 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 PDNA Damage Assessment – Past post-disaster damage assessments in support of a PDNA
have been based on a variety of methods and data sources. Most common were field reports that
attempted to capture the magnitude and scope of the disaster by focusing on heavily-affected
areas and “extrapolating” these observations to the rest of region. In the past decade, remote
sensing technology has had a role in these damage assessments but primarily as a verification
source or as a means to visually portray to decision-makers and the public the amount of damage
that had been sustained in the disaster. The notion of using remote-sensing technology as the
primary basis of establishing the “damage estimate” is new and the fact that the Post-Disaster
Needs Assessment framework adopted by the Haitian government is based on a direct result of
this assessment is noteworthy. What was fundamentally a slow and tedious process was greatly
enhanced by free and widely-available high-resolution satellite and airborne imagery. Rather
than taking months to complete a preliminary count of damaged buildings, the application of
remotely-sensed data allowed this damage assessment process to be shortened by a factor of two
or three.
Currently, the United Nations through its UNOPS initiative are conducting a “house-tohouse” assessment of building damage levels in order to ensure the safety of each building and to
estimate the rebuilding or repair costs of all affected structures. This level of investigation is
considered the most reliable and most accurate indicator of damage and thus represents the
benchmark to which the remote-sensing assessment must be based. Since this process is still
ongoing, a final comparison is not possible at this stage; however, early indications are that the
remote-sensing based results are highly reliable with respect to counts of heavily-damaged or
destroyed buildings
Despite the obvious power of remote sensing technology, it is not without limitations. As
we observed from ground surveys, much of the damage that resulted in the Haiti earthquake
could not be detected from traditional aerial imagery (i.e., nadir views). With damage
phenomena known as “soft-story” failures” ii so prevalent in this earthquake, ground surveys
played an important role in “filling in” the complete picture of damage. One of the key
recommendations of this effort is the need for detailed protocols that systematically identify
where these ground surveys are to be completed and to what extent. Some research is already
being performed to help answer these questions (Saito et al, 2010) iii .
Future post-disaster damage assessments – whether for earthquakes or for other hazards –
will surely include a major remote-sensing component. As the technology improves in both
resolution and delivery, the use of remote sensing will be commonplace not only for the most
spectacular events but for smaller and moderate-sized events. And the Haiti earthquake will
serve as the benchmark for what can and should be accomplished in these disastrous events.
Crowd-sourcing – Crowd-sourcing or human computation is a relatively new
development and certainly a new concept in the area of disaster response. The notion of using a
large community of experts to help perform damage assessments in disasters has been introduced
by a number of individuals and organizations iv . With the Internet becoming the foundation of
“social networking,” it is not unexpected that virtual damage surveys using high-resolution
imagery displayed on “Google Earth” type platforms emerged as a major source of damage
information for the Haiti PDNA. After the Haiti earthquake, hundreds of individuals from
around the globe passionately sought ways of contributing their expertise, time and knowledge to
help support the people of Haiti.
ImageCat working with a network of partners including the Earthquake Engineering
Research Institute v reached out to the engineering and scientific community to help in
4 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 quantifying the extent of damage caused by the Haiti earthquake. In direct response to this
event, ImageCat and EERI formed the GEO-CAN (Global Earth Observation – Catastrophe
Assessment Network) community to help the World Bank in its effort to quantify building
damage. Using very high-resolution aerial imagery, this community was able to identify the
number of heavily-damaged and destroyed buildings in greater Port-au-Prince. A major product
from this effort was the delineation of the pre-earthquake footprints of these buildings that would
later be used by the joint WB-UNOSAT-JRC effort to quantify the amount of building area that
needed to be replaced or repaired. In addition, the footprints offered an efficient way of
combining the damage assessment results from the World Bank effort (GEO-CAN), and the
UNOSAT and JRC teams. Using crowd-sourcing as the main information technology tool for
post-disaster damage assessment, the GEO-CAN community was able to deliver its first count of
damaged buildings in less than a week.
The GEO-CAN community consisted of over 600 experts from 23 different countries
with over 60 major universities represented, about 20 government agencies and non-profit
organizations, and over 50 private companies vi . Current efforts by the World Bank, EERI and
ImageCat are ongoing to institutionalize the GEO-CAN community as a permanent tool in the
World Bank damage assessment toolbox.
Geo-Spatial Products – Led primarily by the UNITAR/UNOSAT group, a myriad of
geo-spatial products emerged throughout the post-Haiti earthquake campaign. Early products
were used for tracking emergency response activities, such as the locations of Internally
Displaced People (IDP). Later products included atlases that showed the locations of severelydamaged and collapsed buildings – see Figure 1. These damage atlas sheets were critical in
deploying emergency teams to assess the safety and integrity of all buildings in the greater Portau-Prince area.
Some other novel applications include 3-D models of Port-au-Prince that were
constructed using LiDAR data collected during the World Bank-ImageCat-Rochester Institute of
Technology Remote Sensing Mission (see Figure 2). A final report prepared by the World Bank
and ImageCat contains a more comprehensive discussion of the various data products that were
prepared by numerous organizations using high-resolution satellite, aerial (both nadir and
oblique) optical imagery and LiDAR data vii .
One of the important lessons learned from the Haiti earthquake was that free access to
high-quality imagery was an important factor in motivating researchers and response
organizations from around the world in producing rapid and transparent damage assessments.
Corroboration of damage results was possible because of the number of independent studies that
were performed in this event. Although manual interpretations of damage were most common,
many studies focused on automated or semi-automated approaches. Over the next year, we will
be able to evaluate what methods were most effective at quantifying the scope of damage in this
disaster. Already several major journals have committed to publishing special issues on the Haiti
earthquake with special attention to remote sensing technologies. Through these reviews and
exchanges in information knowledge, the response community will be able to build on the
lessons learned in the Haiti earthquake so that the process of damage assessment will be even
more robust and efficient in the future.
5 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 Figure 1. Damage Atlas Sheet – Haiti Earthquake
6 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 Figure 2. Purdue University’s 3-D building Models as viewed in Google Earth
Conclusions
While the area of remotely-sensed damage assessment took a quantum step forward in the Haiti
campaign, there is still significant room for improvement. Some of the areas that deserve further
investigation or review are:
1. The establishment of standard operating procedures to ensure that damage assessments
performed by multiple groups are consistent, transparent and combinable. An important
element of any protocol will be standard definitions of damage and a damage scale based
primarily on remotely-sensed imagery. Current efforts by the joint WB-UNOSAT-JRC
team are focusing on a preliminary set of guidelines in this area viii .
2. The availability of high-quality imagery in near real-time. A key factor in the success of
the Haiti response was having access to very high-resolution imagery within a matter of
days. Rapid access to these data allowed a number of operations to proceed with greater
confidence, i.e., deployment of emergency personnel to assess the safety of damaged
structures. The fear of “overcommitting” resources before the priorities were known was
somewhat mitigated by having these early “snapshots” of the devastation caused by the
earthquake.
3. More work in training field personnel in how to use the “derived” products of satellite
and aerial imagery. What was evident from post-earthquake interviews with field
personnel was that existing workflow processes did not include the use of high-resolution
imagery or derived damage products in the early emergency phase. For that reason, the
use of the damage atlas sheets and general damage statistics was limited at that stage.
7 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 Perhaps, an important purpose of the standard operation procedures discussed above
could include clear guidance on how these damage products could be used for building
safety assessments, siting of evacuation camps, siting of relief centers, etc. Additionally,
there is an opportunity to integrate remotely-sensed products into the recovery process.
For example, tracking and monitoring the progress of rebuilding or reconstruction can be
a product of remote sensing technologies.
4. Refining the application of crowd-sourcing techniques in both damage assessment and in
exposure mapping. In Haiti, one of the most severe impediments to the rapid mapping
process was not having quantitative information on what was there before the earthquake.
In most developed countries, property information (parcel locations, building sizes, some
structural data) is typically available through cadastral and tax records or other
government databases. This information is important in identifying what the
reconstruction needs are because it provides data on what existed before the disaster.
Because this information was largely absent in Haiti, a significant amount of time was
spent trying to construct this information post-event by “digitizing” remote sensing
images. Because there are a number of countries that would be in the same situation as
Haiti, refining crowd-sourcing techniques to quickly develop key datasets, including
locations of damaged structures and as spectacularly demonstrated by the Open Street
Map initiative ix , is highly recommended.
5. Exploiting the lessons learned from the Haiti Earthquake. The response to the Haiti
earthquake with respect to technology exploitation was phenomenal. In many respects,
the event served as a testbed for assessing the efficacy of a wide range of technologies,
including remote sensing. The lessons learned from this event must be leveraged so that
when the next mega disaster occurs, we are not “re-learning” how to respond or how to
implement these new and emerging technologies. What is needed is a “tsunami” of
publications, reports, briefs, book chapters that document our successes and failures, in a
way that also guides the way forward for future applications. It is the hope of the current
authors that this book chapter contributes to this mission and that in a small way, we have
defined part of that direction.
Acknowledgments
There are many organizations and individuals that contributed to this joint damage
assessment mission. We would like to acknowledge the following groups/individuals:
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
BFP Engineers, Inc., USA
DigitalGlobe, USA
Earthquake Engineering Field Investigation Team (EEFIT), UK
Earthquake Engineering Research Institute (EERI), USA
EC/Joint Research Centre, Italy
GeoEye, USA
Google, USA
Open Street Map, USA
Pictometry, USA
Rochester Institute of Technology, USA
Stanford University-Pacific Earthquake Engineering Research Center, USA
Swisstopo, SUI
8 | P a g e ‐ 8th International Workshop on Remote Sensing for Disaster Management, Tokyo Institute of Technology, Tokyo, Japan, September 30‐October 1, 2010 ƒ
ƒ
ƒ
University at Buffalo, USA
University of Zurich, SUI
UN/UNITAR/UNOSAT, SUI
i
EMS‐98 scale includes five damage grades: 1 – no visible damage; 2 – minor damage; 3 – moderate damage; 4 – very heavy damage; and 5 – Destroyed. ii
These types of structural failures occur when the stiffness of the lower stories of a building are much “softer” that than upper portions of a building. Soft floors usually result when large open spaces at the first level. The effect when significant ground shaking occurs is for the upper floors to collapse onto the lower story. Many of these failures were observed in Haiti. iii
Saito, K., Spence, R., Booth, E., Madabhushi, M, Eguchi, R. and Gill, S., “Damage Assessment of Port‐au‐Prince using Pictometry,” Proceedings of the 8th International Workshop on Remote Sensing and Disaster Management, Tokyo, Japan, September 30 – October 1, 2010. iv
Coyle, Diane and Patrick Meier, New Technologies in Emergencies and Conflicts: The Role of Information and Social Networks. Washington, D.C. and London, UK: UN Foundation‐Vodafone Foundation Partnership, 2009. v
The Earthquake Engineering Research Institute is a professional organization of engineers and scientists that are dedicated to reducing the effects of earthquake on people and structures. Founded in the late 1960’s, its membership exceeds several thousand individuals. For more information on the organizations and its accomplishments over the last several decades, please see http://www.eeri.org. vi
See http://www.virtualdisasterviewer.com for a complete list of organizations that participated in the GEO‐CAN Haiti Initiative. vii
World Bank – ImageCat, Post‐Disaster Building Damage Assessment using Satellite and Aerial Imagery Interpretation, Field Verification and Modeling Techniques, 2010. viii
Joint Research Centre, UNITAR/UNOSAT, World Bank (GFDDR), ImageCat and Cambridge Architectural Research. Standard Operating Procedure‐ Collaborative Post‐disaster Damage Assessment Using Remote Sensing, 2010.
ix
http://wiki.openstreetmap.org/wiki/WikiProject_Haiti for a description of the OSM crisis mapping activities and http://haiti.openstreetmap.nl/ for access to the map data