Essay - Why do similar kinds of hazards have different impacts in different places? (10 marks)

Hazards are natural processes which effect a population or cause damage to property or environment; they can be geophysical, for example earthquakes and volcanoes, or hydro-meteorological, for example hurricanes, flooding and blizzards. The impact is not only determined by the magnitude of the hazard, but how vulnerable the population or area affected is, this can be shown in the equation: hazard risk = (vulnerability x magnitude of disaster) / capacity to cope. Populations with a low capacity to cope with a hazard are more vulnerable than areas which are prepared well and have the resources to respond quickly. Vulnerability is also influenced by environmental factors, population density and urbanisation.

Comparing two category 5 hurricanes, hurricane Andrew in the U.S, August 1992, and hurricane Mitch in Honduras and Nicaragua, October 1998, can demonstrate the contrasting impacts of similar hydro-meteorological hazards in an LEDC and MEDC. The number of fatalities caused by Hurricane Mitch is estimated to be a staggering 19,000, and many towns were completely destroyed, leaving 600,000 homeless in Honduras. The devastating impact of the hurricane can be attributed to the affected countries’ low GDP per capita and low preparedness. Honduras and Nicaragua are two of the poorest countries in Central America and therefore, lack of money and effective resources meant that there was not proper warning and evacuation systems or effective storm drains, making them more vulnerable. Moreover, houses were not properly constructing and often built on steep slopes due to poor building regulations. In contrast, Hurricane Andrew’s death toll was considerably smaller and stood at 29 people. The affected states were all in the United States, an MEDC; this meant that while the damage caused by the hurricane was severe, advanced communications allowed early predictions and warnings, allowing people to take action to protect themselves. Furthermore, the country’s economic wealth meant buildings and infrastructure could be built and maintained in a way that made them more likely to withstand the effect of a hurricane.                                                             

Another noticeable difference between the effect of the two hurricanes is the economic impact; while the U.S was more prepared for hurricane Andrew and so the damage was less extensive than that caused by Hurricane Mitch, the areas affected by hurricane Andrew have more expensive infrastructure and  buildings which cost the economy more to replace. The overall economic impact of the hurricane was $26.5 billion, whereas the cost of hurricane Mitch was $6.2 billion. Despite the economic cost after hurricane Mitch was lower than that of hurricane Andrew, due to less expensive infrastructure needing repair, the cost of hurricane Mitch was a much higher percentage of the affected countries’ GNP than of the U.S and therefore the countries heavily depended on international aid to support in the rebuild.

The same natural hazard event can cause different levels of impact in different areas of the place affected. This is evident in the varying effects of Hurricane Katrina across districts in New Orleans of varying wealth. It was found that as the percentage of the population living in poverty in different neighbourhoods increased, the percentage of those with a vehicle in which they could evacuate with, and the percentage of those with flood insurance, both decreased. This demonstrates that poverty is a key factor in determining the amount of resources people are able to cope and recover from a disaster, and so vulnerability is positively correlated with poverty of an area.

There can also be different impacts between similar natural disasters in MEDCs due to certain environmental and structural factors. For example, two earthquakes of very similar magnitude occurred within a year of each other and had very different impacts: the Northridge earthquake, January 1994 in Los Angeles, and the Kobe earthquake, January 1995 in Japan. While there was little differences between the power of the two earthquakes and the economy of both the U.S and Japan, 6,000 people and there were 210,000 heavily damaged buildings following the Kobe earthquake, and there were only 61 deaths and 15,000 damaged buildings following the Northridge earthquake. The differences between the scale of the impacts could be explained by two major factors, the soil quality of affected areas and the structural style of the buildings. Studies have shown that the soil in Kobe is much softer than the soil in the affected areas of Los Angeles, making the ground much more susceptible to liquefaction, which would have made the foundations of structures such as buildings and bridges weaker. It was also the case that decades before, the older buildings in Los Angeles had been reinforced, making them more earthquake resistant, whereas in Japan, many of the older buildings could not withstand the force of the earthquake.

Another factor which affects the scale of impact from a natural hazard is population density and how close the event was to an urban area. This is evident when comparing the effects of the September 2010 Canterbury earthquake and the January 2011 Christchurch earthquake, both in New Zealand. While the earthquake in 2010 was of magnitude 7.1 and the 2011 earthquake was much smaller with a magnitude of 6.3, the effects of the 2011 were much greater. In the 2010 earthquake, although there was some damage to buildings, roads and pipes, nobody was killed and very few were injured. However, in the earthquake 4 months later, there were in total 185 casualties, most of which were when the six-storey CTV building in Christchurch collapsed; there were also significant damages to buildings and infrastructure caused by the quake and liquefaction. There are many possible factors which could have caused the large difference in the scale of impacts between the two events. The Canterbury earthquake’s epicentre was much farther from Christchurch city centre than the January 2011 earthquake, and therefore the area affected was much less densely populated and the buildings were mostly smaller, suburban houses rather than tall office buildings, which are much more easily collapsed in an earthquake. Another possible reason for there being far more casualties in the 2011 earthquake is that the 2010 earthquake occurred early in the morning, when the majority of people were still in bed, however, the 2011 earthquake occurred after midday, when more people were out in the city and at work.