Tectonic hazards frequently occur the world over but this does not always result in a risk. There are three aspects that eventually cause the disaster and these are: the tectonic event itself, exposure to that event and whether you are vulnerable to its effects or not. Only when all three of these criteria are satisfied does a tectonic disaster occur. The first of the three cannot be mitigated against by humans as we cannot stop a volcanic eruption or an earthquake occurring. The second factor, exposure is becoming an increasingly more worrying issue as global population continues it’s current, rapid rise. As populations increase, settlements start to expand into regions of regular tectonic activity. This close proximity to the tectonic event increases exposure and hence, the risk of a tectonic disaster occurring. Mexico City is a prime example of where rapid population growth has occurred despite the overlying threat of disaster. The city, with a population of over 21 million, has experienced rapid expansion during the second half of the 20th Century despite being built on top of unconsolidated alluvial sediments. These help magnify the effect of seismic waves in the extremely seismically active region which only serves to worsen the impact of potential earthquakes. Over 5,000 people were killed in September 1985 when a category 8 magnitude earthquake hit the region but this did not seem to deter potential immigrants. The third factor that contributes to earthquake risk is the vulnerability to an earthquake and this is the area that can be most easily mitigated against although, an authority’s ability to do so is massively dependent on their economic position.
Mitigation against a tectonic disaster has three components: plan, prepare and respond. In order for a government to be able to do these, they must have first have the correct perception of the event, they must be able to perceive the danger and understand the need for mitigation. They must also have sufficient wealth available to them in order for them to successfully mitigate which is why there are such large disparities between mitigation levels in developed and developing countries.
In developed countries, the government can afford to plan and implement schemes both in advance and subsequent to an event. This can involve action response plans to reduce the social impacts of disasters after they occur or building earthquake resistant structures. All of these actions reduce the countries vulnerability to a tectonic event therefore the disaster risk and effect is minimised. This was particularly evident in Japan after the 2011 Tohoku earthquake. It was given a value of 6 on the Modified Mercalli Intensity scale, . This is described as moving household items and potentially cracking poorly constructed masonry and plaster. Considering this was an earthquake of magnitude 9.0 (Richter scale) , the 4th largest (reliably recorded) earthquake since 1900 , the damage caused was not of a similarly massive scale. This is reflective of the large sum of money the authorities have invested in the engineering and construction of earthquake defences in the area. In San Francisco, an area infamous for both the Loma Prieta quake of 1989 and the San Andreas (and other) fault, the Department of Building Inspection spent over 9 years and $1 million developing the Community Action Plan for Seismic Safety to help mitigate the effects on society of another earthquake . These actions were only possible because of the large amount of capital at the authority’s disposal.
In contrast, developing countries cannot afford this luxury. Often, they have neither the perception nor the wealth to implement mitigation schemes against the tectonic hazards in their vicinity. After the Indian Ocean earthquake and resulting tsunami, certain Islamic scholars in Indonesia claimed that as more women were killed than men, the tsunami was a result of God being displeased with women. They then suggested that the way to avoid another tsunami would be for the women to strictly conform to Islam . This opinion clearly contradicts prevailing scientific thought and is obviously an unwise and impractical method to mitigate against tsunamis. Beyond perception, the poor financial standing of developing countries also prevents them from successfully mitigating against tectonic events resulting in them being extremely vulnerable to hazards. In January 2010, Haiti experienced an earthquake of magnitude 7.0 (Richter scale) , 100 times smaller than the one in Tohoku. However, it registered as a 9 on the Modified Mercalli Intensity scale . This means that there was great damage to buildings and structures, many of which were shifted in their foundations. This evidences the poor levels of earthquake resistant construction in the country, synonymous with the lack of available finances to do so. In developing countries, an economic positive feedback loop is formed. As the country cannot afford to mitigate against a hazard, they feel the full force of its effects. They expend wealth in an attempt to recover from the damage, meaning their financial situation worsens further and they can afford less still to spend on mitigation…
Often when authorities are considering developing mitigation schemes for tectonic hazards, they undergo a cost-benefit analysis to assess its financial viability. Mount St, Helens, in Washington, USA, is a brilliant example of where a cost-benefit scheme has been successfully implemented to provide a sustainable economic approach to disaster management. In the immediate surroundings of the volcano, there has been a huge influx in the number and variety of leisure opportunities since the start of its series of eruptions on May 18 1980. These include camp sites, zip wires and more educational facilities such as the Forest learning Centre and Johnstone Ridge Observatory . The wealth generated through admissions tolls and subsequent tourism is invested in monitoring tools and services which allow volcanologists to predict imminent eruptions and as a result, successfully implement warning and potential evacuation programmes.
Once a tectonic hazard, be it volcanic or seismic, has resulted in a disaster its effects can be divided into three main categories. The immediate effects, secondary effects and finally the follow-on effects. The immediate effects are the direct result of the physical process itself. For an earthquake, this would be the initial propagation of the ground, a tsunami, the submergence by the wave and a volcano, the projectiles emitted from the volcano itself which range from lava and pyroclastic flows to micro scale features such as fumeroles and geysers. Coming into contact with any of these could easily result in fatalities however, they themselves have no economic effects.
Secondary tectonic effects are those caused as a direct result of the physical process and these have a huge economic implication. Whether it is the shaking of the earth or the rapid onslaught from a tsunami or a pyroclastic flow, they all destroy swathes of property and infrastructure and the resulting damage and repair costs leave a huge financial burden. However, what is noticeable after tectonic hazards occur is that the total economic cost has varying financial impacts on countries of differing degrees of development. In developed countries, infrastructure and buildings are both extensive and of extremely high value. Although most of the structures in earthquake zones in developed countries are built to withstand seismic activity, inevitably some will suffer considerable damage which because of their high value, results in extremely high repair costs. In contrast, in developing countries, infrastructure and buildings are nowhere near as extensive or costly. As previously mentioned, the vast majority are not built to an earthquake proof specification so when it hits, there is widespread destruction however, their low value means the actual damage costs are not that high. Whilst this first appears to be favourable to developing countries, when you consider damage costs relative to the country’s wealth, developing countries can very rarely afford to cope with the disaster whilst developed countries can. It is believed that it will cost £181 billion to reconstruct all the structures damaged in Japan during the 2011 Tohoku earthquake , which was 4.7 percent of Japan’s Gross Domestic Product at the time of the disaster . In contrast, the repair costs for the Haiti earthquake of 2010 are only £7.6 billion , just 4.2 percent of the damage costs of the Tohoku earthquake but 156% of Haiti’s GDP at the time . This emphasises just how devastating the secondary economic impacts of a tectonic hazard are to developing countries.
The economic costs of secondary tectonic effects are clearly apparent however, the follow-on effects, potentially the most damaging and long lasting of them all, are often overlooked. As mentioned, tectonic events destroy a whole host of infrastructure which if not rapidly repaired, has a knock-on economic effect. For instance, the longer businesses remain in their damaged state, the longer they go without trading and the greater the financial loss. Disruption to the transport system after a disaster prevents the distribution of both imports and exports throughout the country which reduces sales and as a result, income. This effects not only the authority’s wealth but that of the individual tradesmen and citizens too. Their reduced levels of trade result in a diminished amount of disposable income which means less capital gets spent in the tertiary sector of the country’s economy and the economic situation only worsens. As is becoming the trend, a country’s ability to solve the infrastructure issues quickly are in a large part dependent on the wealth available to them. After the Tohoku earthquake of 2011, there was widespread destruction and damage to the Japanese road system however, with money at their disposal, within 6 days large areas of destroyed road network were reopened and fully operational. This helps minimise any disruption to the transport of goods and aid around the country and as a result minimises the financial strain landed on Japan. In contrast, Haiti were not able to fix damaged infrastructure at such a swift rate. The earthquake destroyed many structures critical for the sanitation and health of the population. The government is unable to afford the repairs and these unsanitary conditions are a large contributing factor to the rapid spread of cholera around the island. Since the earthquake in 2010, over 700,000 people have become infected by cholera and over 8,000 have died  due to the lack of suitable infrastructure to both combat the disease and to properly care for those infected individuals. Infrastructure is not the only thing damaged during tectonic events that causes knock-on economic impacts. When Mount Pinatubo erupted in June 1991, as well as emitting pyroclastic flows, it also triggered large scale volcanic mud flows. These flows covered and destroyed over 219,840 acres of rice farmland , and the resulting diminished yield caused massively reduced incomes for farmers throughout the affected region. This point could be argued against as volcanic regions actually create extremely fertile soils which may in time produce an overall increase in productivity but for a considerable period of time, this land will remain unfarmable. There are considerable problems when you are trying to assess the economic impact of the follow-on effects of a tectonic hazard. They are ongoing processes and problems with no distinct end point so it makes it extremely hard to measure and report on their financial effect as the cost is always escalating.
The reduction in media coverage in tectonic disaster areas is also in part responsible for the inability of less developed countries to deal with the follow-on effects. When the event happens, news teams provide worldwide coverage of the primary and secondary effects. At this point, aid tends to flood in and an aid budget is pledged to the country to help them rebuild what has been damaged. However, as time progresses the story tends to fall out of international news and off of the international agenda and as a result, it has its aid budget slashed. This is particularly evident in Haiti at the present .
Whilst developing countries don’t always experience greater magnitude physical hazards than developed countries, the secondary and knock-on implications always have a larger detrimental economic effect, even if their outright cost is smaller. This is due in part to their economic inability to mitigate against the potential tectonic disaster.
Contributed by Joseph Everest, Geography Editor