why do natural disasters happen in poor countries

Earthquakes As we have just noted, large earthquakes occur much less frequently than smaller earthquakes. Those with magnitudes greater than 8. 5 only occur once every 3 years on the average (see Table 3. 3 in your text or
Is the Frequency of Natural Disasters Increasing? Are natural disasters becoming more frequent as it seems from news reports of recent activity? The short answer appears to be that yes, natural disasters are increasing in frequency (see But, this suggests some other important questions before we start making conclusions about the end of the world: Is the frequency of hazardous events increasing?

Why is the frequency of natural disasters increasing (what could explain the trend)? First, Is the frequency of hazardous events increasing? This is much more difficult to answer since natural events responsible for natural disasters have been occurring throughout the 4. 5 billion year history of the Earth. Nevertheless, there is no evidence to suggest that hazardous events are occurring more frequently. What about global warming? There is evidence to suggest that weather related disasters are becoming more frequent, compared to other disasters like earthquakes. For example, the frequency of disasters from tropical cyclones and floods has been increasing, the frequency of earthquakes has changed little.

Although this is what we expect from global warming, there is not yet enough statistical data to prove this right now. Second, is there another explanation for the the frequency of natural disasters increasing? First consider the following facts: Human population has been increasing at an exponential rate. With more people, vulnerability increases because there are more people to be affected by otherwise natural events. Human population is moving toward coastal areas (see ). These are areas most vulnerable to natural hazards such as tropical cyclones, tsunami, and, to some extent, earthquakes.

Our ability to communicate news of natural disasters has been increasing, especially since the invention of the internet. Earlier in human history there may have been just as many disasters, but there were few ways the news of such disasters could be communicated throughout the world. Meanwhile: Deaths from natural disasters has decreased in developed countries and increased in developing countries. What could explain this? Politics? Economics? Cultural Differences? Education? The cost of natural disasters has been increasing in developed countries.

What could explain this? Economics? This Course This course is not about the political, cultural, or economic aspects of natural disasters. It is about the science of natural disasters and how can use our knowledge of the scientific aspects of disasters to reduce the death and destruction caused by otherwise natural events. Textbook Theme We will discuss each of these concepts for each of the hazards we study. Finally, Kunreuther and Michel-Kerjan explore setting up early disaster warning systems. Based on existing studies and research from Stephane Hallegatte, they find that early warning systems in developing countries would require less than $1 billion a year and would have direct benefits (reductions in the losses from disasters) of between $1 billion and $5. 5 billion per year.

There are additional benefits, such as the reduction in evacuation costs, the reduced costs to the health care system, improved continuity of education (from preserving schools), reduced social stress, and avoided business interruption, which is worth at least another $3 billion and possibly $30 billion. In total, the benefits could range from four to 35 times their cost.