By John Pike, director, GlobalSecurity.org
(www.globalsecurity.org),
Alexandria, Va.
On Dec. 26, 2004, a magnitude 9.0 earthquake off the coast of
Sumatra triggered dozens of massive aftershocks northward along the
Andaman and Nicobar Islands, spawning the massive tsunami waves that
shattered tourist resorts and seaside communities from Thailand to
East Africa. The initial shock was the world’s fourth largest
earthquake since 1900, and the largest in more than 40 years. With
the human death toll surpassing 200,000, the event is one of the
deadliest natural disasters in modern history.
The catastrophe’s true magnitude gradually unfolded during the
following days. The devastation along the coastal areas of the
Indonesian island of Sumatra, closest to the initial shock, was
guaranteed. Destruction was so complete that for the first few days
there was only silence from these areas. Then the world slowly began
to grasp the true magnitude of the calamity. As in the past, news
organizations dispatched their reporters and cameras to the scene,
and their audiences saw familiar scenes of mangled buildings and
lives.
But some of the first glimpses of affected areas were provided by
high-resolution commercial satellites, which arrived much sooner
than their earthbound counterparts. During the days and weeks that
followed, the Indian Ocean tsunami became one of the most intensely
observed events of modern times. Satellite operators across the
globe devoted collection resources to the relief effort, and imagery
exploitation enterprises around the world devoted unprecedented
resources to the task at hand. The imagery vividly illustrated the
tsunami’s human, social and environmental toll. The result was a
remarkable snapshot of a major world event compiled by an
astonishingly diverse community that was only a distant dream a
decade ago.
A First Glimpse
At 10:20 a.m. in Sri Lanka on Dec. 26, a few hours after the
earthquake and just moments after the tsunami impact, DigitalGlobe’s
QuickBird satellite captured a stunning image of the southwestern
coast of Sri Lanka. The image showed high water at least one
kilometer inland of the Kalutara resort area, revealing churning
ocean movements resulting from the receding water. On Dec. 28,
DigitalGlobe’s public relations team issued an e-mail alert about
the image’s availability to international media. Within hours, the
image appeared on Web sites and in news reports around the globe,
prompting dozens of relief organizations to request the image for
mapping and damage-assessment purposes.
Others approached the image from a different perspective. Mohamed
Faizeen, manager of
the Centre for Islamic Studies in Colombo, Sri Lanka, saw the hand
of Allah in the
tsunami, specifically in the churning waves it spawned near Kalutara.
“This clearly spells out the name ‘Allah’ in Arabic,” says Faizeen.
Indeed, only slight imagination was required to follow his venture
into imagery interpretation.
DigitalGlobe continued to collect imagery of the hardest hit areas
in the Indian Ocean region and, on Dec. 29, issued another image
alert showing Banda Aceh, Indonesia, at the earthquake’s epicenter.
Showing a markedly changed shoreline, where floods reached further
than three kilometers inland, as well as large piles of debris and
severely damaged or obliterated buildings, this imagery—aided by
“before” shots taken in June 2004—gave the world a visual
understanding of the event’s unthinkable devastation.
Again, widely differing perspectives derived vastly different
meanings from the same images. Wrote Jonathan Schell, peace and
disarmament correspondent for The Nation and author of the 1982
best-seller The Fate of the Earth (a book about nuclear war that
galvanized millions), “As would happen in a nuclear war, villages
and small cities were scoured from the face of the earth. ‘Before’
and ‘after’ satellite photographs even showed the erasure of
geographic features of the landscape. … Like photographs of bombing
damage, the before photos showed the fine articulation of human
cultivation and dwelling—in this case, a salad of greenery laced
with lines of red tile roofs and roads—and the after pictures were a
smear of browns.”
Writing a few days later on www.aljazeerah.info, Kaleem Hussain
remarked, “ … in Indonesia … vast terrain has been destroyed only to
find a mosque where the praise of the Divine is mentioned standing
unscathed by destruction that has traveled from one subcontinent to
another. This links succinctly with the story of Noah’s Ark and how
the community of the prophet were saved at that time.”
Disaster Relief Efforts
The following vignettes provide a glimpse of the myriad tsunami
relief activities:
• The National Geospatial-Intelligence Agency (NGA) assisted other
U.S. government agencies in assessing the extent and scope of damage
caused by the tsunami. NGA provided imagery products of the affected
areas on a daily basis to the U.S. Agency for International
Development’s Office of Foreign Disaster Assistance (OFDA); the U.S.
Pacific Command (USPACOM), in whose region the tsunami occurred; and
to other U.S. government agencies supporting humanitarian relief
activities.
NGA used its commercial satellite imagery contracts to fulfill
customer requests for information on the scope of the damage. OFDA
and USPACOM used the products to determine the priorities for
emergency relief efforts, and where life-supporting supplies and
personnel needed to be deployed. NGA also assessed impacts to
infrastructure, particularly damage to roads, bridges, ports and
airfields. The assessment of how the damage affected access to the
damaged areas helped the U.S. Transportation Command (USTRANSCOM)
and others provide assistance in the region.
•
Within hours of the tsunami, the U.S. Geological Survey National Center
for Earth Resources Observation and Sciences (EROS) began providing
relief organizations worldwide with pre- and post-tsunami satellite
images, as well as image-derived products that incorporate information
on population density, elevation and other relevant topics. Responding
to the urgent needs of governments and service organizations, these
products were placed in an easily accessible Web site to help relief
organizations make practical, well-informed decisions as to where relief
efforts are most urgently needed and how best to carry out those
efforts.
USGS provided population distribution map books that were updated with
pages listing the numbers of potentially affected people, assuming
tsunami impact heights of 5, 10 and 15 meters, with summaries by
administrative unit. The population data are based on Landscan 2003 data
from Oak Ridge National Laboratory. The elevation data are based on the
Shuttle Radar Topography Mission (SRTM) 90-meter digital elevation
model. These maps portrayed different scenarios based on possible
tsunami impact heights. The exact level of impact wasn’t known when the
maps were made, so the different scenarios didn’t necessarily represent
the actual situation on the ground. The maps were used as tools for
informed users with the understanding that impact heights may vary along
coasts of a region.
• As
of mid-January 2005, Space Imaging’s IKONOS spacecraft had acquired more
than 90,000 square kilometers of imagery covering affected areas.
Following the tsunami, the spacecraft was tasked continuously to do
strip mapping over the area. The company’s Singapore regional
affiliate—the Centre for Remote Imaging, Sensing and Processing (CRISP)
at the National University of Singapore—focused on collecting imagery of
Sumatra, while its U.S. partner was focused on many of the other
affected areas. NGA was by far the largest single customer, and for the
cost of reproduction, USGS acquired all of NGA’s imagery. “The IKONOS
satellite is basically a mapping machine in orbit,” says Mark Brender,
Space Imaging’s vice president for Corporate Communications. “When
coastlines change and the lay of the land is altered, IKONOS satellite
imagery becomes crucial for humanitarian relief purposes.”
• The “International Charter for Space and Major Disasters” was
activated in response to several calls to ensure acquisition of
satellite data over the areas hit by the tsunami. Extensive coverage of
the disaster by the European Space Agency’s Envisat and ERS satellites
was planned until the end of January, and data acquisition from the
agency’s PROBA experimental satellite occurred Jan. 1-4. In solidarity
with the tsunami-affected countries and on UNOSAT’s request, CERN made
available the infrastructure for its Imagery Bank at no cost.
•
Earth Satellite Corp. donated more than 15 million square kilometers of
imagery from its global NaturalVue 2000 imagery data set to support
disaster recovery and reconstruction efforts. Imagery data sets have
been provided to the United Nations Office for the Coordination of
Humanitarian Affairs and the U.S. Department of State.
• From Eurimage, all QuickBird imagery acquired over the areas affected
by the tsunami, both before and after Dec. 26, was made available to
institutional, governmental and nonprofit organizations involved in
disaster recovery at a 30 percent discount. Due to the unprecedented
demand, bandwidth problems surfaced at both EiNet and DigitalGlobe, and
catalog users initially experienced difficulties.
• Taiwan pledged support in various ways. The country’s FORMOSAT-2
satellite, launched in May 2004, was among the first to successfully
acquire images of Thailand’s Phuket Island and Banda Aceh, Indonesia—two
of the most heavily hit areas—and download the data to its ground
station in Hsinchu City, Taiwan. Working with researchers at several
Asian universities, Taiwan’s National Space Program Office (NSPO)
immediately processed the images and provided them to aid rescuers in
those areas. FORMOSAT-2 continued to collect imagery of seriously
affected areas, and NSPO provided the imagery to the affected countries
for free.
Myriad Benefits
Satellite imagery was an important tool to help disaster relief planners
understand the scope of the damage, and allocate resources quickly and
efficiently. Such imagery also gave the public a way to grasp the
overwhelming magnitude of the cataclysm, and perhaps contributed to the
massive outpouring of contributions to the relief effort. While the
satellite images brought citizens from around the world closer to the
destruction, they did so from a safe distance, allowing people to
approach without being overwhelmed.
