Monday, 13 February 2012

Dan Sharpe: Contrasting Earthquakes in Christchurch and Haiti

Dan Sharpe, aged 19, is a second year geology student at the University of Leeds. With an avid interest in travelling, he has recently spent three and a half months in the wilderness of Northwest Canada and has also climbed the highest active volcano in the world. Currently fundraising for his participation in the Milan City Marathon in April, Dan spends most of his time out of lectures running or in the pool, or the pub of course.

Dan has a keen interest in development and will be joining the GfGD Blog writing team as a columnist - covering topics of interest to him - and hopefully many of you, enjoy!

Source: Flickr
2011 was a year of unparalleled numbers of disasters and the first six months saw over $265 billion in losses (study by Munich Re; a company that specialises in disaster insurance). On the 10th January floodwaters rushed through Queensland Australia, waters that killed 17 people and caused millions of dollars of damage; an event that carried on affecting lives through to February. This month also saw a devastating earthquake hit Christchurch New Zealand, and this 6.3 magnitude hazard was the largest of six earthquakes to strike the city on the 22nd February. 182 people lost their lives as a result of this event which, for such a large and repetitive series of earthquakes, is considerably lower than it may have been. In comparison to another hazard event in 2010, this low death toll is nothing short of remarkable. The earthquake that shook the capital of Haiti in January 2010 recorded 7.0 on the Richter Scale, but the death toll came in at over 300,000. Both earthquakes occurred at a relatively shallow depth increasing their severity, and both had an epicentre less than 25km from the cities so why was one so much more deadly?

Marco Dormino/UNDP
The slums surrounding Port-au-Prince, Haiti, are some of the worst in the world. Corrugated iron and wooden shacks are built on foundations of unconsolidated mud and rock. Liquefaction of these poor foundations means these temporary living spaces easily collapse, entombing the residents inside. All of the main buildings had inadequate building quality and no earthquake protection technologies, so many collapsed partially if not entirely including the three medical centres. In contrast, the buildings of Christchurch are soundly constructed and much more resistant to earthquakes. The hospital, although partially damaged, remained open throughout the event to treat the injured and although nearly a quarter of the residential buildings in the city centre are expected to be demolished, few collapsed in the event itself ensuring the survival of most residents.

In developing regions, response mechanisms need great improvement. NGOs and foreign governments can only do so much to repair the damage done by a natural disaster, so greater internal support and infrastructure is needed to respond rapidly to a hazardous event. For three days after the Haiti earthquake the only medical facility was the Argentine Military Field Hospital and survivors were left to search for victims buried in the rubble, alive or dead.

Geoscience Education (c) GfGD

The role of the geologist is to identify and to teach. With a better understanding of earthquakes in developing regions comes the opportunity to reduce risk through reducing vulnerability. Working with regional and governmental geologists to map areas of poor foundations and poorly consolidated ground can also inform risk reduction. The earthquake on the 10th January 2010 was different because of the geology itself. The shallow depth of the earthquake meant more energy reached Port-au-Prince and the geology and relief of the surrounding area ‘funnelled’ the waves down towards the city. With stakeholders having a better understanding of the regional geology, more preparation could have saved countless lives two years ago. A lack of geological analysis of this developing nation, however, left it blind to the problems it then faced. Installing a basic knowledge of geosciences in schools and government departments could help reduce risk before hazards even happen, surely a crucial way of building resilience and reducing vulnerability, thus bringing Haiti’s death toll closer to that experienced in Christchurch.