In the months following the devastating earthquake and tsunami that struck
the Indian Ocean region on Dec. 26, 2004, U.S. Geological Survey (USGS) scientists
and their colleagues around the world have been working hard to learn from the
tragedy so that such loss of life does not happen again. Stopping these forces
of nature is not part of the plan — we know that extreme events like the
giant earthquake off the coast of Sumatra are part of how the earth system goes
about its business. But we can make every effort to keep natural hazards from
becoming human disasters.
The first lesson from Sumatra is the need for tsunami warning systems wherever
coastlines are vulnerable to tsunamis. Such a system was established by the
National Oceanic and Atmospheric Administration (NOAA) for parts of the Pacific
Ocean following deadly tsunamis that struck Alaska, Hawaii and the U.S. West
Coast in the 1950s and 1960s. In January, President Bush proposed expanding
that warning system, which includes tide gauges and deep-ocean tsunami-detection
buoys, to cover the Pacific and Atlantic oceans and the Caribbean Sea. A number
of nations have offered to provide tsunami warning systems in the Indian Ocean
region, and the United States is encouraging the use of the Global Earth Observation
System of Systems framework to address the need for coordination and interoperability
across systems.
Because tsunami warnings begin with rapid earthquake reporting, the president
has proposed to increase the number of telemetered U.S. Global Seismographic
Network (GSN) stations that can report their data in real time. Today, only
80 percent of GSN, which is funded jointly by the National Science Foundation
and USGS and managed by the IRIS Consortium of universities, has that capability
and thus can be used for rapid earthquake location. The real-time data is fed
directly to the USGS National Earthquake Information Center (NEIC), and from
there over dedicated lines to NOAA’s Pacific and West Coast-Alaska Tsunami
Warning Centers.
The proposed initiative will upgrade hardware and software systems at NEIC —
some of them 20 years old — and implement 24/7 operations there and at
the tsunami warning centers to improve the timeliness of global earthquake alerts
and tsunami warnings. The president has also proposed installing new GSN stations
in the Caribbean, where the subduction zone has generated a magnitude-8 tsunami-causing
earthquake as recently as 1946.
Seismic stations, deep-ocean tsunami-detection buoys and tide gauges are one
part of a tsunami warning system, but a second lesson from Sumatra is that information
has to be effectively disseminated to the people in harm’s way. It is a
formidable challenge to sustain the necessary communications networks for a
single hazard, particularly one that strikes with relative infrequency.
Fortunately, we already have the example to follow of emergency managers in
Washington State, who developed the All-Hazard Alert Broadcasting system (or
AHAB) to provide tsunami warnings on beaches. These pole-mounted sirens, lights
and speakers are connected to the state’s emergency alert system and can
be used for multiple threats. A planned deployment in Seattle later this year
will warn not only of tsunamis but also of human-caused emergencies such as
hazardous materials accidents and possible terrorist threats.
The third lesson from Sumatra is that the value of warnings depends on a public
that knows what to do with them. A big part of the challenge is public education,
but before officials can tell people where to go, they need to know what ground
is high enough and which escape routes will be accessible. Disseminating such
knowledge means having accurate inundation maps, which in turn require bathymetric
and topographic data along with geologic studies to constrain the maximum likely
impact.
In the United States, the president’s proposal would accelerate NOAA’s
inundation mapping and modeling efforts as well as its “TsunamiReady”
community preparedness program. In the Indian Ocean region, USGS scientists
are participating in international teams to document the inundation heights
and collect other information crucial for future modeling. In February, USGS
geologist Brian Atwater brought scientists from the affected countries to his
field sites in Chile to learn how to reconstruct the history of past tsunamis.
The fourth lesson from Sumatra is that infrequent events do happen with devastating
consequences. Much of the reason for the lack of a tsunami warning system in
the Indian Ocean is simply that such events are infrequent. The last major basin-wide
tsunami was in 1833 following a great earthquake further south along the Sumatra
coast, a zone that is now being studied for the potential stress-triggering
effects from the Dec. 26 event as well as the subsequent March 28 magnitude-8.7
quake. Even longer ago, the Bay of Bengal suffered such a large tsunami. Natural
disasters create teachable moments, in this case raising awareness of the possibility
of disaster, no matter how infrequent.
Television certainly played a role in bringing this event home from the other
side of the world, and it also brought home the risks faced in the United States.
Those of us involved in responding to media questions saw a rapid shift from
wanting to know what happened over there to asking whether it could happen here.
A month after the event, I was in St. Louis speaking at a business forum during
Missouri Earthquake Awareness Week. The place was packed. They weren’t
worried about a tsunami on the Mississippi, but the powerful 1811 to 1812 New
Madrid earthquakes suddenly seemed far less remote after witnessing the devastation
of an even less frequent visitor to the Indian Ocean.
The challenge now is to turn awareness into action. Recognizing that there is
much that can be done, USGS is planning a major initiative to deliver the tools
that the public, emergency managers, and public and private-sector decision-makers
all need to reduce the impacts of catastrophic natural hazards. In addition
to tsunamis and earthquakes, the initiative will focus on floods, volcanoes,
landslides, wildfires and hurricane impacts.
The challenge is big, but anyone who has heard the accounts or seen the footage
from Sumatra, from Thailand, from Sri Lanka and from India knows that it is
a challenge well worth pursuing.
 |
Geotimes Home | AGI Home | Information Services | Geoscience Education | Public Policy | Programs | Publications | Careers  |