The disaster that shook the world. The Indian Ocean/Boxing Day Tsunami of December 26, 2004 remains one of the most devastating natural disasters in recorded history. Almost 230,000 people are dead or missing and over 1 million displaced as a result of a series of waves that stretched as far as 2 km inland and towered almost twenty times above the height of an average adult.
The tsunami was generated by a massive undersea earthquake (between magnitude 9.1 and 9.3) near Sumatra in Indonesia. The waves claimed lives in Indonesia, across South Asia and in East Africa, even traveling as far as the Pacific Coast of Mexico and Chile. About one-third of the casualties were children. In South East Asia, a region heavily dependent on tourism, fishing and agriculture, the destruction of the environment and infrastructure by crashing tonnes of salt water will have economic and social costs for decades to come.
It could happen here. At home in a chain of islands similarly prone to earthquakes and volcanic activity, we in the Caribbean have become more aware of our vulnerability to tsunamis. The UWI Seismic Research Unit (SRU), led by Dr. Richard Robertson under the Vice Chancellor and Pro Vice Chancellor for Research, has been monitoring earthquakes and volcanoes in the Eastern Caribbean for more than half a century. Mr. Lloyd Lynch, Instrumentation Engineer at the SRU confirms the disturbing news. “Essentially the Caribbean faces substantial risk for tsunamis. Most of the islands have invested a great deal in coastal resources that are exploited for tourism, commerce [and residences]…If one of these catastrophic events should happen here, a lot of lives could be lost.”
A tsunami is an ocean wave or series of waves caused by an abrupt disturbance of the sea floor. They can be generated by earthquakes, landslides, volcanic eruptions, explosions or even the impact of asteroids, meteorites or comets. As demonstrated by the Indian Ocean disaster, tsunamis can travel at high speeds (500 to 1,000 km/h) for long distances. However, they often pass unnoticed at sea, forming only a passing “hump” in the ocean until they reach shallower water near coastlines. At that point the height of the waves dramatically increases, releasing their destructive energy. The destruction of coral reefs, sand dunes, mangroves and trees leave coastlines more open to the wave’s worst effects.
The Caribbean is exposed to all possible sources of tsunamis. The Indian Ocean disaster highlighted two of these types of risk. That is, teletsunamis or waves generated in another part of the world rushing to our shores across the Atlantic Ocean and secondly, tsunamis triggered by shallow, powerful earthquakes in the region itself. Furthermore, there is the risk posed by large volcanic eruptions at or below sea level. Kick ‘em Jenny, a live submarine volcano off the coast of Grenada, can be a future source of tsunamis. And as Mr. Lynch of the SRU points out, “Many of the islands are volcanic. Some, such as Montserrat and St. Vincent, have experienced eruptions in recent times. Who knows when the next eruption will be?”
We are also at risk for tsunamis caused by landslides. According to the SRU, offshore submarine landslides are perhaps the most problematic tsunami danger facing the region. Since they are more difficult to predict and detect, there is less time to warn people of danger. With tsunamis in general time is often scarce, as some strike within minutes from their place of origin.
What you can do. Heeding the warning signs of an impending tsunami and immediately taking evasive action can save lives. During the Indian Ocean event, on an Indonesian island, folklore recounted an earthquake and tsunami in 1907, prompting the islanders to flee to inland hills after the initial shaking. In Thailand, Tilly Smith, a 10-year-old British tourist, had studied tsunamis in geography class at school and recognised the warning signs of the receding and frothing ocean. She and her parents helped to evacuate the beach safely. People also spoke of animals moving inland prior to the tsunami. Mr. Lynch of the SRU adds that “some tsunamis produce loud sounds like a jet plane taking off” as the wall of water approaches the shore. If there isn’t time to get to high ground inland he advises “vertical evacuation” i.e. climbing something strong and high. “Most people are killed by either drowning or crushing by cars and so on in the water. If you are aware of this, you will be in a better position to protect yourself.”
Early warning. The Indian Ocean catastrophe demonstrates that tsunami education and early warning are essential if the Caribbean is to reduce our risk of disaster. In light of this, the Intergovernmental Oceanographic Commission (IOC), through the Intergovernmental Co-ordinating Group for the Caribbean and Adjacent (ICG-CARIBE EWS), is coordinating the establishment of a Tsunami Early Warning System for the Caribbean as well as countries in Central and South America. The system comprises four main steps: 1) detecting possible sources of tsunamis e.g. earthquakes and volcanic eruptions, 2) detecting whether ocean waves were generated by monitoring water levels, 3) communicating this information to 24-hour “focal points” on each island, such as meteorological offices or police stations and, 4) sending out warnings from the focal points to vulnerable communities via sirens, phones and media broadcasts.
Initially, one Regional Warning Centre will be established to coordinate the system. The University of Puerto Rico and the Venezuelan Foundation for Seismology (FUNVISIS) are each bidding to host this centre. In the interim, the IOC has set up four working groups to ensure that the Warning System gets up and running. The groups are responsible for Tsunami Monitoring, Disaster-Preparedness, Hazard-Mapping and Vulnerability, Warning Guidance and Communication.
The Guardians. “You all putting in cable?” was a question posed to the staff of UWI’s Seismic Research Unit by curious observers during the installation of a satellite dish on their headquarters in St. Augustine, Trinidad. The dish is in fact a Very Small Aperture Satellite (VSAT) terminal that will facilitate real time transmission of data from five seismic stations.
The SRU is playing a leading role in establishing this System as part of the ICG-CARIBE EWS team. The Unit is one of several regional agencies that will be responsible for the first leg of the system that is, monitoring the seismic activity that could generate tsunamis and communicating this information to the relevant groups. With a network of sixty seismic stations in the Eastern Caribbean, the SRU is well-placed to fulfill this responsibility.
Accurately identifying the large earthquakes that can cause tsunamis, while transmitting and processing the data fast enough to provide early warning, required a technology upgrade for the Unit. This was made possible through the generous support of the USAID Office of Foreign Disaster Assistance (USAID/OFDA) and the Government of Trinidad and Tobago. The US$249,680 grant enhanced the monitoring stations on St. Kitts, Dominica, St. Lucia, St. Vincent, Trinidad and Tobago. The SRU also worked with the US Geological Survey (USGS) to install three similar stations in Barbados, Grenada and Barbuda. When the entire project is completed over the next two years, each seismic station will be able to detect and report potential tsunami-generating earthquakes in about three minutes.
Education and empowerment. In June, the SRU trained representatives from the 24-hour focal points who will alert vulnerable communities of approaching tsunamis. This is one of a series of workshops for participants in the Tsunami Warning System. The Unit is also working closely with the Caribbean Disaster Emergency Response Agency (CDERA), which received funding from the USAID to coordinate public education on tsunamis. Mrs. Stacey Edwards, Education and Outreach Officer at the SRU, outlined their strategies for sharing information with the wider community. These include public lectures and school visits, a new website with a section focused on tsunamis, information material, exhibitions and educator kits. In addition to expanding their crowded physical facilities, Dr. Robertson reveals the Unit’s hopes to develop a Learning Resource area for visitors, with multimedia presentations on earthquakes, volcanoes and tsunamis.
Saving our lives. “Everything that we do impacts on people’s lives.” For this reason, Dr. Robertson encourages The University, private sector, NGO’s and governments to make more use of the SRU’s resources and expertise. Support for the Unit’s educational outreach, as well as funding for staff, research and technology, can go a long way toward mitigating disasters in the region. This is a goal that is personally important to members of the SRU’s diverse team, many of whom hail from the islands.
For all of us connected to the Caribbean, the danger is close to home. A lot still needs to be done by the IOCARIBE coordinators, but we all have work to do. After all, these are our lives. So it is up to us to ensure that we learn the lessons, listen to the warnings and above all, get prepared.
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