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In 2013, the powerful typhoon Haiyan struck the Philippines, which resulted in more than 7 thousand casualties. In 2011, a great earthquake with a Richter scale reading higher than of 9.0 struck eastern Japan, which resulted in over 2 thousand deaths and a nuclear meltdown. Although there are claims that technological means to overcome natural disasters exists already, natural disasters are still common and are still causing great damage and loss. Setting aside whether these disasters could have been forecast, it is questionable whether such disastrous aftermaths and damages are truly inevitable. Are natural disasters truly natural, and is the devastation caused by such incidents impossible to be prevented?

Some say people should not regard mother earth as an object that is at humanity’s disposal and that humans should coexist with it. However, human history so far does not abide with such claims, and has developed in a way to allow humans to take full advantage of the environment. Such actions are based on an anthropocentric view of nature, that humans should conquer and overcome the nature which originated in the West. Examples include construction of structures that can overcome natural fluctuations, such as dams and reservoirs. Buildings were also designed to be more stable and resilient, and our systems of responses to natural disasters have also improved significantly.

 

The Definition of Natural Disasters – Are They Immortal?

Before answering the question whether natural disasters are truly natural, there lies a need to explicitly define natural disasters. According to the conventional definition, natural disasters are defined a s “ any event or force of nature that has catastrophic consequences.” Professor Yoo Chul Sang (Architectural, Civil, & Environmental Engineering) defined natural disasters as any events that happen in the nature, which is beyond humans’ capabilities. The noticeable part is that they are defined as events noticeable part catastrophic consequences. As history progresses and as technology advances, humans’ ability to react to natural disasters has also developed, and as a result, the damage caused by natural disasters has lessened, and so does the definition of natural disasters has changed.

Take earthquakes for example. The worst earthquake that has ever happened, taking the resulting number of casualties as the criteria, is the 1556 Shaanxi earthquake, which resulted in over 830 thousand deaths. The next worst earthquake is the 1976 Tangshan earthquake, which resulted in over 255 thousand deaths. However, looking at the severity of such earthquakes, one could easily tell that those were not recorded as earthquakes that caused the most casualties because their scales were the largest of all recorded earthquakes. 1976 Tangshan earthquake had a magnitude of 7.5 on the Richter scale, and for the 1556 Shaanxi earthquake, the magnitude was 8.0.

It can be said that the severity of the damage is not in direct proportion to the magnitude or severity of disasters, but rather determined by how people react to it and what countermeasures have been prepared. For instance, the 2011 Tohoku earthquake and tsunami had a magnitude over 9.0 on the Richter scale, which is more than 30 times greater than the 1556 Shaanxi earthquake, caused only 20 thousand casualties. It can also be said that the definition of natural disasters is not permanent, but rather susceptible to change.

The events of nature that were earlier regarded as natural disasters, like drought and flooding, are no longer regarded as such, at least not in the same scale as before. Minor scale droughts and flooding that caused a great deal of damage in the past when the systems to react to were not fully established are no longer causing such damage, and hence no longer regarded as natural disasters. In addition, minor earthquakes, are no longer regarded with fear, at least in some nations like Japan, where the systems to react to them have been successfully established.

In other words, the concept of natural disasters is not solid or definite, but is susceptible to change and is changing, as humans come up with better solutions to such disasters. Although the occurrence of such natural disasters cannot be prevented or perfectly forecast, depending on how well people have prepared for such incidents and how well people can handle such hardships, the results can differ greatly.

 

 

   
▲ Earthquake crumbling down buildings. Provided by globalprotectiveservices.com

 

 

   
▲ Alberta flood inundating the city. Provided by disasterforum.ca

 

These kinds of preparations, according to Professor Yoo, are non-structural measurements of preparation, and claimed that these could be considered even more important than developing technologies to enhance the level of safety of structures, which he refers to as the structural means of preparation. “Technology gaps between countries are not the most influential factor which contributed to the difference of casualties between nations which were subjected to similar size of natural disasters; rather, it is the difference on non-structural means of preparations that is most influential,” claimed Yoo.

 

Seismic Disasters

Professor Yoo defines natural disasters as those that are not caused by humans. These disasters, therefore, are naturally harder to predict and prepare for, mostly because of their randomness in nature. Volcanoes and earthquakes are the result of the movements of tectonic plates, which are massive, irregularly shaped slabs of solid rocks generally composed of both continental and oceanic lithosphere. Their movements cannot be forecast except only a few hours prior to their occurence, confirming their unpredictable nature.

Most architectural structures in a society are clustered around cities. The components of a city include buildings and transportation systems. All the economic activities occur there, and should an earthquake happen in those places, almost every single aspect of a society will collapse, including human lives and a country’s economy. To prevent such catastrophes and their aftermaths, a country must have a set of actions that minimize the impacts of natural disasters.

First, all the structures built in a society must be constructed so that they can withstand earthquake of any scale. According to Professor Kang Young Jong (Architectural, Civil, & Environmental Engineering), this type of construction involves seismic design. The cost of building a structure with this specific design differs by the scale of the earthquake expected. For example, structures in Japan are almost always subject to huge-scale earthquakes, usually around the magnitude of 5.1 Mw (Moment magnitude scale). This is why they all require a very strong seismic design, whereas structures built in Korea are not as subject to huge-scale earthquakes as Japanese ones are, thus not needing such strong seismic design.

 

   
▲ A blueprint of Seismic design. Provided by ssieng.com

 

Professor Kang adds that vibration isolation construction is another structural measurement of earthquake prevention. What is also important other than the structures of the buildings themselves is their construction in relation to the ground on which they are constructed. Earthquakes usually send out shockwaves in a horizontal direction and very rarely do they pass the waves in a vertical direction. That is why such construction method is required in buildings. Once structures are built accordingly to the said methods, they will find themselves immune to surface vibrations of any scale spread through the ground.

So far, only the structural measurements of prevention have been discussed, but Professor Kang stresses that non-structural measurements are just as important as structural ones. One of those mechanisms include earthquake drills. What should be noted is that all non-human methods of disaster prevention are rendered useless if residents do not possess adequate disaster awareness. Even if individuals are taught basic safety procedures (training), this awareness still makes the job of the structures much less burdensome. Regions where tectonic plates are still very much active such as California and numerous parts of Japan require their residents to participate in annual earthquake drills.

Another one of the mechanisms Professor Kang mentions is a conduct manual. It is a natural human instinct to panic when one faces a crisis. To be able  to consciously make sound decisions, one must have a conduct manual. The conduct manual will have the power of organization and further minimization of the harm caused by the disaster. However, it is ultimately up to the disaster site managers to handle the situation.

Setting the priorities for each building is another procedure a city could take to lessen the effects of earthquakes. To simply put it, there needs to be a hierarchy among buildings; some buildings are more vital to human society than others, so they must be protected first. These important structures include hospitals, schools, and the roads that lead them. If these three were to collapse, other structures existing in a city would be rendered obsolete.

Thanks to statistics, scientists can somewhat accurately predict when and where a disaster will happen. As mentioned previously, earthquakes are caused by the movements of the tectonic plates, which exert a large force onto the earth’s crust up to the critical point when it cracks open. When the earth opens, the rocks will experience a slippage and rebound to a less deformed state, and while this is happening, energy is sent out in the form of seismic waves which causes earthquakes. This whole cycle, from when the force accumulates to when the rocks rebound, repeats again and again, and this repetitive nature can be used to predict the date and location of a future earthquake.

 

   
▲ Dams to prevent droughts .Provided by www.britishdams.org

 

Hydrological Disasters

Floods are commonly believed to be caused by heavy rainfall, but there lie many more culprits behind the phenomena, ranging from topography to tidal influences. The same goes for droughts. Some of the factors include El Nino, erosion, and climate change. In other words, human societies should always be ready for such catastrophes.

Prior to delving into ways to prepare for floods and droughts, Professor Yoo makes a distinction between the two. Floods have huge impacts in a very short amount of time, but their influence do not usually last long. Droughts, on the other hand, have a relatively smaller impacts in a very long period of time, and their effects last for a very long time. Moreover, floods tend to elicit a cooperative behavior from humans, whereas droughts tend to do the exact opposite.

Professor Yoo reveals that the most widely known and most common method of preventing floods is to build dams. Dams are basically barriers that confine water or underground streams. They must control the water levels so that space for surplus water during heavy rainfalls or other forms of large-scale precipitation, including hail and snow, is available. Dams have proved to be effective in preventing inundation, but other options do exist.

Another structural measurement Professor Yoo addresses is a levee, or embankment, which is either a naturally occurring ridge or an artificially created wall. Naturally occurring levees are usually located near lowland rivers and creeks, and they maintain a shape very similar to artificial ones. Their mechanics are pretty simple, which are to simply trap water into their reservoirs placed lower than the surrounding ground.

Levees and dams, however, have been frequently criticized for their drawbacks. Their most common failure is levee breach, which refers to a great amount of water flooding into unwanted places when part of the embankment suffers erosion or fails. Levees must constantly have their reservoirs managed, but if they become overfull, then the ridges immediately become useless. Despite the drawbacks, they have been the most successful in preventing floods. 

 

Assessments and Analysis

Now the question arises: Are these prevention methods truly effective? Professor Yoo answers this question by comparing China and Japan, two countries whose structures are constructed in completely different manners. Chinese structures lack Seismic design and vibration isolation construction whereas in Japan they are fully equipped with them, so it was no surprise when the death tolls of each country during shakeouts differed.

The 2008 Sichuan earthquake, which had a magnitude of 8.0 Mw, took more than 7 thousand lives. On the other hand, in the 2011 Tohoku earthquake, which had an even greater magnitude of 9.0 Mw, 15 thousand died, meaning that the prevention methods worked. It should be kept in mind that a 9.0 Mw earthquake is ten times stronger than an 8.0 Mw earthquake.

The previous example shows that the measurements of prevention, whether they are structural or nonstructural, cannot ignore their ties to the economy. If a nation can afford to focus on projects which do not bring immediate results, then they are good to go, but if it has starving citizens, collapsing buildings and virulent diseases, then it cannot channel much of taxpayers’ money into projects that might seem extravagant. The former usually refers to developed countries such as the U.S., Japan, and many European countries, and the latter usually points to underdeveloped countries such as Haiti, the Philippines, and Vietnam.

For earthquake prevention, developed countries can afford to build more rigid seismic designs in preparation for a huge earthquake that happens once a century, whereas underdeveloped countries can only afford to construct less rigid seismic designs ready for imminent earthquakes that happen every 20 years or so. The same difference can be observed in hydrological disaster prevention. Developed countries can build dams and levees which can handle the loads of large-or medium-sized rivers, but the underdeveloped countries can only build architectural structures for small-sized streams.

Interestingly, however, Korea is classified in the latter category. Professor Kang said that “Korea is generally prepared for an earthquake. Korea, however, does have many defects in its prevention methods.” Some of the defects Professor Kang mentioned are in relation to fire and electric explosions.

Professor Kang claims that these aftermaths of an earthquake are just as damaging to human society as an earthquake itself and that Korea is definitely not prepared for these dangers. “What is the use of having seismic designs and vibration isolation constructions when you cannot even do anything about a fire or electric explosion?" he asked. He also added that Korea also lacked a conduct manual during the event of an earthquake.

Professor Yoo also sided with Professor Kang in that Korea was not fully prepared in the case of seismic disasters. Earthquake drills have been thoroughly implemented at random, unexpected times in developed countries for a long time, but these so-called, “shakeout,” have been very recently implemented in only selected parts of Korea at specific times since the end of the former President Roh Moo-hyun’s term.

Despite the defects Korea has, Korea is still generally prepared for natural disasters. It is just that Korea seems to overly concentrate on the hardware aspect of prevention and not the software aspect. Seismic designs and levees can only do so much, and the more effective method of minimizing casualties is to focus on what individuals can do for themselves.

   
▲ Professor Kang Young Jong emphasizing the significance of seismic design. Photographed by Jung Woo Jae

 

What is More Important Than Mere Technological Preparations

Looking at examples of natural disasters that could have been prevented, it is wiser to say that not all natural disasters have to result in the loss of human life and habitation, but are poorly managed. Although complete prevention of such incidents like 2010 Haiti earthquake is impossible, if adequate measures were taken or systems were built, the damage done could have been significantly reduced. If the same system available or used in Japan or other nations were set up in Haiti, the damage would not have been as severe.

The technological developments and support to develop measures which could forecast the occurrence of natural disasters are important. Yet, what is more important is the development of nonstructural measures which assist people to wisely handle such disasters. It is wiser to prioritize on providing adequate education and the formation of social bonds of sympathy in a society than developing technologies which could prevent a building from collapsing. This is not only because a social consensus should be arrived at before making preparations for natural disasters, which take significant funding, but also because such thinking is necessary to minimize the damage done by natural disasters.

Professor Yoo claims that the reasons for the drastic differences in casualties between countries which were subjected to similarly intense disasters lies in such factors. The most significant example could be Typhoon Rusa. It hit both Japan and Korea in 2002, but the number of casualties differed greatly; it resulted in more than 200 casualties in Korea, but only a single victim in Japan. The most significant factor for such a difference, Professor Yoo claims, is the difference in non-structural measures, encompassing such issues like education and the citizen consciousness.

Every safety net involves an expense, and it can be said that such measures are appropriate only if the expenses do not exceed the potential harm such disasters would do to the society. Professor Kang claimed, “By providing a safety net to disasters, we are assuming that such disasters would hit our society and do harm, and that such provisions are there only because there are definite convictions that such a disaster would happen.”

He uses seismic designs as an example. “Let’s say we build buildings that could stand in an earthquake which would normally occur on a ten-year basis. By designing such buildings, we are assuming that one out of ten buildings would collapse due to such a disaster.” Kang asserts it is unwise to blindly increase the level of safety measures, for it may seem like an overreaction and could be economically less than optimal.

Both Professors Kang and Yoo claim that although the economic expenses and technology which could minimize the damages of natural disasters are important, what is more important is the education of the citizens that are at stake, and the widespread social consensus about the severity of natural disasters and the seriousness of its impacts.

Although many are critical about how well Korea is preparing natural disaster, both professors claim that the structural measures against natural disasters in Korea are already acceptable, considering the conditions of our economy and current situation. Professor Yoo stresses that although Korea has been investing heavily in providing structural measures against natural disasters, little has been done to provide non-structural measures, and such aspect is the problem that Korea needs to address.

The complete surveillance of nature and perfect prediction of natural disasters are distant goals, and it is uncertain whether such acts are possible or even desirable. Rather, what can be done now is getting ready for natural disasters by providing both structural and non-structural measures against such disasters, and certainly the latter is what our country should focus more on. Korea has begun preparing such measures only recently, and it is true more time is required for them to take hold. Yet such goals can only be achieved once a social consensus is reached, and that is what should be the priority of our nation for the next decade. We are not powerless in the face of natural disasters, but we do make ourselves powerless by not adequately preparing ourselves, and some action needs to be done.

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