Prepare! Earthquake could hit any day
The ESL Blogs produced by Environmental Solutions Ltd, a Kingston-based environmental management consultancy.
Indonesia 2004. Haiti 2010. Japan 2011. On the surface, these three countries don't seem to have anything in common. However, they do have one tragic link: each has been hit with a major earthquake that has resulted in severe destruction and loss of life.
The Indonesia quake, measuring 9.1 on the Richter scale, goes down as one of the 10 worst in history and the tsunami it triggered claimed almost 227, 900 lives. Closer to home, we watched the news in horror as image after image of almost total devastation came out of the Haitian capital, Port-au-Prince, where a magnitude 7.0 quake struck, levelling buildings all across the city, from the Palais National - the president's official residence, to family homes.
The exact death toll has been in dispute, but estimates stand at 220,000, with a further 300,000 people injured and many more still living in cramped, unsanitary tent cities around the capital almost four years later.
Although it would seem that there have been more frequent destructive earthquakes over the past few years, that is not the case. As devastating as the three referenced quakes were, they are actually the exception rather than the rule.
Millions of tremors
According to the United States Geological Survey (USGS), several million earthquakes occur annually, but most are too weak to have an impact or take place in remote, uninhabited areas where their effects are not known.
The seemingly increased frequency may be explained by the fact that there are now more than 8,000 seismograph stations around the world today, compared to just 350 in 1931, which makes it much easier to locate quakes. Improvements in ICT, which allows the data to be disseminated more rapidly, also play a part.
The Caribbean is no stranger to earthquakes. The Port Royal, Jamaica, disasters of 1692 and 1907 stand out, along with the 1947 quake in El Cibao, Dominican Republic, which is believed to be the largest recorded earthquake to have occurred in the region. It reportedly measured magnitude 8.1 and generated a tsunami that caused 75 deaths and rendered 20,000 homeless, with aftershocks extending through 1947 and 1948.
Geologically, the Caribbean is located in a hotbed of seismic activity. The northern territories, including Jamaica and the island of Hispaniola, which is shared by Haiti and the Dominican Republic, are located on or near major fault lines, where the majority of quakes occur as a result of the friction between the Earth's tectonic plates.
The Eastern Caribbean islands, such as Trinidad and Tobago, Antigua and St Lucia, were formed at a subduction zone, where two tectonic plates meet and the denser one sinks beneath the lighter plate. This has resulted not only in earthquakes, but in volcanic activity as well.
Ever since the Haiti quake, seismologists have been warning regional governments and national agencies to prepare for even more dangerous quakes and tsunamis in the future. In December 2010, acting director of the Seismic Research Centre of the University of the West Indies (UWI), Dr Joan Latchman, urged us to be prepared for a magnitude 8.0 earthquake, which could strike 'any day'.
Last January, the UWI's Earthquake Unit also warned that Jamaica is due to experience an earthquake on the same scale as the one that sank a section of Port Royal more than 300 years ago.
Quakes in cycles
"We believe these are cycles, but we don't know the recurrent intervals. Some calculations have been done based on the history of earthquakes. We don't know what has happened before. We have not done enough research to understand the history of earthquakes prior to this. So any calculations that have been done or any recurrent interval that is calculated is just based on a short history, so it's really not accurate," explained Dr Lyndon Brown, research fellow and head of the unit, in a Gleaner story.
Given our history, people in the Caribbean should certainly heed the warnings, but just how does one go about preparing for something as unpredictable as an earthquake?
One of the most reliable methods of planning for an earthquake is adherence to proper building codes and no-building zone legislation, which will empower governments to prevent construction in disaster-risk areas. A presentation done in 2010 by Noel daCosta of the Jamaica Institution of Engineers reveals that Jamaica does not have a mandatory up-to-date building code. The code currently in use is from 1908 - ironically, one year after a massive earthquake ravaged Kingston and Port Royal. An updated code was published in 1983 as a policy document and is not enforceable. Additionally, a regional code, the Caribbean Uniform Building Code produced in 1985, is also not enforceable.
Therefore, local engineers decided to adopt the International Building Codes. DaCosta also shared some statistics from recent earthquake-stricken areas that reveal the importance of adherence to building codes. A magnitude 6.5 earthquake struck both Paso Robles in California, USA, and Bam in Iran in December 2003. In Paso Robles, where buildings were code-compliant, 46 were damaged and two people died. Conversely, in Bam, where structures were not code-compliant and built ad hoc, about 85 per cent of the city was destroyed and more than 30,000 lives were lost.
The most recent push for current building codes is the Build Better Jamaica project, part of the Developing Design Concepts for Climate Change Resilient Buildings by the Institute of Sustainable Development at the University of the West Indies. The project, funded by the International Development Bank, seeks to, among other things, push the Government to pass and enforce an updated building code that will place more emphasis on maintaining the integrity of the natural environment while designing and constructing buildings that are more resilient to natural disasters and the effects of climate change.
In addition to developing and enforcing adherence to proper building codes, emergency-service departments across the region must be fully equipped to respond in extreme cases. Currently, that is not the case. In Jamaica, many fire stations, for instance, are barely able to respond to a house fire, let alone the burning of a city block that could potentially occur during an earthquake. Equally important is the need for each country's local emergency management body to be properly staffed and funded.
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