The extent of the tragedy in Haiti reveals itself further as time goes by. The Haitian Interior Minister stated last week that the verified death toll to date is more than 217,000 people whilst estimates of total lives lost to date are appearing to begin to settle around 230,000. In addition to this it is estimated that some 300,000 people were injured in the quake, that more than 500,000 are currently homeless and that some 5 million are currently dependent on aid to survive.
The scale of the impact of this tragedy is hard to assimilate – so much death and destruction in such a confined area. The life lost so far is now getting on a par with the 2004 tsunami where it is estimated that some 250,000 (USGS NOAA figures: 225,000 – 275,000) died. The Sumatra quake and subsequent tsunami was much larger however, and its geographic range of impact vast. The race is on now in Haiti to put in place shelter and services before the rains come. As rain, in make-shift camps with poor hygiene, brings with it the spectre of waterborne diseases.
So why did the Haiti quake kill so many people? The answer lies in the harsh combination of risk and vulnerability. Port-au-Prince, the capital of Haiti, lies on what is called the Enriquillo-Plantain Garden fault system which is in the boundary region separating the Caribbean and North America tectonic plates. This means that the area is at risk of seismic activity and whilst this particular fault system has not produced a large quake in recent decades it does have a history. In 1751 a major earthquake to the east of Port-au-Prince destroyed the city. In 1770 the city was again destroyed by a quake this time centred to the west of the capital. In 1860, further west again, there was a major earthquake which caused a tsunami. So the risk is clearly there.
Vulnerability is more complicated but centres on the terrain, the relative poverty of the people and of course the every high population density. The combination of these factors means that damage caused by a quake particularly in terms of loss of life is likely to be high.
Finally, to compound these factors the quake had a large magnitude, its epicentre was close to the city and critically it occurred very shallow in the earth’s crust. So at 21.53 hrs on January 12th a magnitude 7 quake with epicentre just 25 km west south west of Port-au-Prince at a paltry depth of 13km hit the city and enormous death and destruction ensued.
In the coming months when final figures are applied to the Haiti quake it will fall within the top 10 deadliest natural disasters in recorded history. Looking at the current top 10 it is notable that 6 of the 10 worst events have occurred in China a country, of course, with a very high population density. Of those disasters 4 were floods and two were earthquakes. The yellow river in China accounts for 3 of the top 5 worst natural disasters in history: in 1887 it flooded and killed 900,000-2,000,000 people, the 1931 floods are estimated to have taken between 850,000 – 4,000,000 lives and just 7 years after that it flooded again to take a further 500,000 – 900,000 lives! In the latter half of the 20th century the Yellow river has been tamed by major flood prevention works until today in fact there is insufficient water in the basin to meet the growing human, agricultural and industrial demand.
In the last decade earthquakes have been responsible for nearly 60% of fatalities caused by natural disasters globally.
Now when we consider the Seychelles scenario we face different issues. As noted in previous posts Seychelles is blessed to lie far from the edge of its tectonic plate and outside of the cyclone belt, whilst floods on our tiny islands drain rapidly into the sea.
The central archipelago is not immune from cyclones of course, they are just rare. A 2007 disaster management capacity assessment for Seychelles cited a worst case scenario of a major cyclone hitting the east coast of Mahe. The east coast harbours our major population centre, something like 90% of our food storage facilities, the port and international airport, as well as the bulk of power generation, fuel storage and health care capacity. Food for thought!
The vulnerability of our east coast was further underlined by the 2004 tsunami. Much of the contingency planning measures addressed by the current World Bank project will be looking in depth at the vulnerability of that area and how to reduce and mitigate this. Over the coming months this blog will cover these issues in more depth... do keep checking back for updates!
For those interested to investigate further the risk and vulnerability issues that affect fatalities there was a very interesting article on the BBC website recently that compared these factors in 3 recent earthquakes, that of Haiti and the 2008 China and 2009 Italy quakes. To read the article, follow the link below:
http://news.bbc.co.uk/2/hi/americas/8510900.stm
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