Comparing two similar earthquakes of identical magnitude– 7.0 on the richter scale
and duration–45 seconds: the Haiti earthquake on 12th January 2010, and the San
Francisco earthquake on the 27th of October 1989, illustrates clearly the extent of the
impact that the coping capacity and vulnerability of a population has on the scale of
a natural disaster, shown by the disaster risk equation. There were many similarities
in the physical features of the two earthquakes in addition to the magnitude and
duration such as the fact that both had a shallow focus – Haiti’s was 13km and San
Francisco was 21km The earthquakes were formed at conservative plate margins,
which is where two tectonic plates are sliding past each other, causing friction which
results in a sudden ‘jerks’ and releases energy as seismic shock waves.
Despite the physical similarities of the earthquakes, the effects of these disasters
were extremely different. Where the death toll was just 62 in San Francisco, more
than 225, 000 fatalities were reported as a result of the Haiti earthquake, with the
majority of deaths caused by being crushed by collapsing buildings. One of the major
causes for the extremity of the Haiti disaster in comparison to a similar earthquake
was the level of economic development of the country which had a significant effect
on the vulnerability and ability of the population to cope with such a hazard.
In San Francisco, a more economically developed city and a member of the G8– a
group of the richest trade economies– the population’s vulnerability was relatively
low. This was due to a number of factors, particularly the measures put in place to
reduce the impacts of earthquakes which were very common in the area. Unlike
Haiti, which had a corrupt government and therefore no preparation or planning for
disasters (reducing the coping capacity of its population), San Francisco had
developed Life Safe buildings, intended to move with the seismic shock waves thus
reducing the risk of collapsing buildings. Additionally, drills were practised regularly
in order to educate the population as to how to respond should such a disaster
occur. One example of this is the instruction to get under a table or doorway – the
strongest area in a building, if seismic waves were felt. All of these resulted in a
much greater coping capacity of the population of San Francisco, a great contrast to
the population of Haiti.
Haiti’s highly vulnerable population was contributed to by the instability of Haiti’s
government, highlighted by the periodic violence and UN and NGO involvement, as
well as the lack of economic development and therefore poor building quality and
infrastructure which was the most significant causal factor in the high death toll.
This resulted in the hazard becoming a humanitarian crisis with 86% of the capital’s
population still in temporary camps and 1.3 million homeless, in contrast to the
economic disaster of San Francisco where insurance claims were $680 million. The
economic damage of Haiti’s 2010 earthquake was estimated to be $7.8 billion with
19 million cubic metres of rubble and debris in the capital of Port au Prince.
The comparison of these two examples of natural hazards shows how far the
economic development of a country can impact upon the coping capacity of a
population, resulting in a death toll 3,630 times higher. The major factor of the
building quality – being the main cause of deaths in Haiti- is a key example of the
extent of the effect human factors on the impact of a natural hazard and its risk.
Q2) Describe and Explain the global distribution of tropical hurricanes