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The Death Toll from the Turkey and Syria Earthquake Surpasses 20,000 as of February 10th. The Tragedy Raises Questions on Preparedness and the Role of Modern Science in Providing Adequate Data for Authorities to Protect Lives. What Measures Should be Taken?
Why can’t earthquakes be predicted in advance?
Predicting Earthquakes: An Impossible Task. Claims of Earthquake prediction are either fraudulent or based on misunderstandings. The triggers for seismic activity are rooted in the random processes within the Earth’s mantle, making prediction extremely difficult. Similar to the unpredictability of weather patterns, predicting earthquakes is even more challenging due to the complexity of monitoring activity deep within the Earth. In geophysics, we can only understand the general movement of tectonic plates and monitor the build-up of stress at their boundaries, which may lead to earthquakes in the future. However, the exact timing and location of earthquakes remains beyond our ability to predict.
Some earthquakes start with small jolts. Many animals are capable of feeling them, and their alarmed behavior can indicate the approach of a disaster. With the desire, such observations can be considered as a form of forecasting. Another option where predictions work is aftershocks, i.e., secondary jolts that usually occur after a major earthquake (but the value of such short-term forecasts is not very high). Unfortunately, the overwhelming majority of earthquakes start immediately with strong jolts, and there are no ways of accurate prediction for them.
The forecasts that scientists can still give usually relate to very long periods of time. They sound, for example, like this:
The US Geological Survey estimates the probability of a major earthquake in the San Andreas fault area in any given year to be 0.3%. This is equivalent to one earthquake of magnitude 7.8 once every 300 years.
In some cases, the period when an earthquake is expected may be significantly shorter. A bright example of this is northern Turkey: the dynamics of the movement of lithospheric plates in the Marmara Sea region is such that scientists expect strong earthquakes here within not hundreds, but only tens of the nearest years. Back in 2000, an American-Japanese group of seismologists made a much more specific and alarming forecast for the region:
The probability of strong earthquakes in Istanbul – (62 ± 15)% within 30 years, and with a probability of (32 ± 12)% – in the following 10 years.
What specifically causes the majority of deaths during earthquakes?
Strictly speaking, it is not the earthquake itself that kills, but the movement and collapse of buildings: either falling ceilings or furniture, glass fragments, and other objects flying around. The damage can be further increased by fires that often start at the site of the destruction.
The quality of construction is the main parameter that determines the number of casualties. In other words, with the same intensity of mechanical stress on buildings and the same population density, fewer people will die where they build better. This thesis may seem obvious, but we will still provide references to several articles where it is clearly confirmed by data:
- US Geological Survey conducted a study on settlements affected by earthquakes from 1900 to 2007.
- Cambridge conducted a study on risk factors during earthquakes.
- World Bank has an internal document with the title “Why Do People Die During Earthquakes?”
What structures are particularly dangerous?
Light brick and stone structures and concrete homes without steel reinforcement are the easiest to collapse. However, a reinforced concrete frame is also an unreliable protection if substandard materials are used. Sand-diluted concrete and construction in close proximity to the tectonic plate boundary are cited by Transparency International as the main reasons for deaths as a result of the powerful 1999 Izmit earthquake in Turkey.
Another important factor determining the number of deaths is the strictness of building requirements. Buildings constructed in Japan after the 1981 review of building codes, as a result of the 1995 Kobe earthquake, fell much less frequently than buildings constructed before. Most often, houses built before 1971, when the requirements for flooring and columns were tightened, fell.
How expensive is it to prepare a house for an earthquake?
The technologies for protecting buildings from underground shocks are divided into two types:
- The first is building reinforcement; in this case, engineers give the bearing structures the ability to withstand larger loads (for example, through X-shaped beams, steel sandwich structures, etc.);
- The second type of technology, on the other hand, reduces the load that the bearing structures bear. For example, one of the most reliable solutions is considered to be shock absorbers (or isolators), which are installed between the building itself and its foundation and do not allow the foundation vibrations to enter the building. There are many types of construction, usually rubber-steel dampers with lead cores are used. One of the most interesting solutions, for example, is used in the new Apple office in California – the building is not anchored to the ground at all, but is supported by metal balls that are clamped between curved platforms- “dishes” that can slide freely between the “dishes”.
Reinforced buildings are more expensive to build than ordinary buildings, but to what extent depends on the situation.
Different estimates show that the protection of buildings from earthquakes can sometimes cost half the cost of construction, but rarely more – and sometimes even cheaper: everything depends very much on the location, building size, and ground.
For example, Nepalese specialists in 2019 calculated the cost of building a seismically protected small-sized house (multi-apartment buildings are not as relevant in a country where most of the houses are built by the owners themselves). The calculation for 17 variants of a residential house showed that the difference in the cost of a reinforced and non-reinforced house on average is 16.67%.
Malaysian specialists give different estimates: depending on the type of soil, the construction of a two-story earthquake-resistant school building may be 34-111% more expensive than building using regular technology (for a two-story option), and 22-55% higher if the school is four stories.
It doesn’t matter how much seismic force you need to prepare for — the difference in additional construction costs will be small. According to a recent Greek study, as you move from one level of seismic risk to the next, the need increases by a fraction of a percent, with little impact on the cost of the entire reinforced structure.
Protecting a building built without seismic protection is more expensive than building it with seismic protection from the beginning.
According to assessments by building technology specialists from Bangladesh, modifying a already-built three-story building will cost 22-92% (depending on the chosen method) of the cost of building a reinforced building from scratch. The most reliable method is the most expensive: foundation insulation, which costs almost as much as building from scratch. In the end, in terms of efficiency and cost, two other methods come out on top – replacing bearing walls with reinforced concrete and laying new reinforcement; both are cheaper than foundation insulation.
The question of how much it will cost to strengthen cities located in seismically active zones is periodically raised. The cost of strengthening 3600 previously built public buildings in Istanbul, for example, without seismic protection, was estimated by the World Bank in 2005 at one billion dollars.
In other words, the transformation of a residential area into an earthquake-resistant fortress may cost, depending on the type of building, almost twice as much as the construction of exactly the same area without seismic-resistant structures.
At the same time, restoring a city destroyed as a result of an earthquake will cost 100% of its construction cost. That is, on average, waiting for an earthquake and building a new one turns out to be cheaper than strengthening old buildings. This is without taking into account the funds spent on crisis response, expenses due to the cessation of work of enterprises, business life, disruptions in supply chains and much more. Not to mention loss of human life.
Modern technologies, in principle, allow to build buildings almost perfectly protected from any possible disasters. An example of this is nuclear power plants, the buildings of which are designed for earthquakes with a magnitude of nine points or a direct plane crash on them.
Building every building to nuclear power plant standards might be excessive. How to determine the measure of reasonable protection?
“Building every building to nuclear power plant standards might be excessive. How to determine the measure of reasonable protection? The calculation of benefits and costs of measures that reduce risks (such as building earthquake-resistant buildings and reinforcing old structures) depends on several factors. Economists usually attribute to them:
- the cost of protective measures
- the risk of a catastrophe
- the probable scale of a catastrophe
- the volume of probable losses
- the profitability of investments
Indirectly, part of these calculations includes such a value as the cost of human life. The ethics of using this parameter can be discussed, but economists use it to explain economic decisions made by ordinary people or government representatives.
One of the most detailed studies on the cost-benefit ratio was conducted after the 1999 Izmit earthquake in Turkey; the results of these studies were used to make decisions on World Bank financial aid to the country. The cost of serious injury in this case was estimated at eight thousand dollars, the loss of a human life was valued at 200 thousand dollars.
Despite these low parameters, the authors of the study still came to the conclusion that some buildings in Istanbul need to be rebuilt, reinforcing the load-bearing structures, some need to be demolished and new, seismically resistant buildings constructed, and all of these measures in the long term are economically justified. The project was funded by the World Bank and completed in 2015.
However, with lower risks of disaster and a lower cost of life assessment, the outcome may be different. For example, in very poor regions where increased spending on construction can mean reduced spending on other necessities such as medicine or education.
Research on the economic behavior of residents in seismic zones shows that investments in protection or earthquake insurance are also extremely unpopular in wealthy countries if they are not required by law. Furthermore, expenditures for protection from earthquakes (as well as floods and other natural disasters) seem to be rarely popular among voters, at least in the United States.
There may be many reasons for this situation, but studies show that the issue is certainly not that people know little about earthquakes: the situation does not change immediately after major disasters and when residents of the region have long forgotten what an earthquake is.
Among the real reasons may be economic and political culture. For example, when comparing very different seismic protection practices in Japan (where it is very widespread) and the United States (where it is almost absent), experts among other things indicate that in the states buildings change owners much more frequently, so there are much fewer economic incentives to invest in long-term protection there. Additionally, in the US, tradition gives much more economic decision-making, such as the choice of construction technology, to private hands.
But the main thing is that the number of earthquake victims directly correlates with the level of corruption.
The decisions taken at the state level on measures to protect against earthquakes are not always implemented in practice. And at least partly, corruption may be to blame for this.
A 2007 study in which scientists analyzed data on the consequences of 344 earthquakes in 42 countries from 1975 to 2003 showed that the higher the level of corruption in the state, the greater the number of earthquake victims. Another study, which included 269 major earthquakes that occurred from 1960 to 2002, showed a direct relationship between the number of deaths and social inequality. Scientists explained this connection by the inability of societies with a large gap between rich and poor to take collective action – the introduction and control of compliance with building regulations, the strengthening of structures and zoning based on the degree of seismic threat.
Finally, in 2011, Nicolas Ambraseus, one of the most well-known earthquake specialists, specializing precisely in the Mediterranean region, summarized these observations in an article for Nature with the telling title “Killed by Corruption.” Using data analysis of earthquake victims in different countries, their GDP, and the level of corruption perception, he showed that 83% of all victims over the last three decades lived precisely in corrupt countries — those where the level of corruption was higher than could be expected based on their GDP.
Ambraseus links this to the fact that in the case of earthquakes, the consequences of insufficient compliance with construction technologies and standards become apparent.
The construction industry is widely recognized as the most corrupt segment of the global economy. Corruption takes the form of bribes for the violation of inspection and licensing processes, as well as secret actions that lower costs and thus reduce the quality of construction. Building construction, from pouring the foundation to applying the final coat of paint, is [by nature] a process of concealment, a process that is ideal for reducing or completely eliminating the use of expensive but important construction components. <…> During earthquakes, the consequences of decades of poor construction quality are revealed on a catastrophic scale.
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