According to the interviewee, what brings South Central Asia higher risk?

W: Welcome to our program. I’m Linda Poon. This week we bring you a story on dangerous buildings. Sometimes science isn’t enough. Technology can be expensive or unavailable or impractical. In the case of engineering buildings in earthquake zones, these shortcomings can be deadly. Today, Roger Bilham will talk with us about the dangers of poorly built buildings in south central Asia and what roles science and technology can play to alleviate conditions there.
M; In our short perspective, we recognize some of the issues of earthquake in South Asia, which have been central to our studies, but we focus on the rather special problem, which is the fragility of dwelling units throughout the region—houses which are capable of falling down in the night without an earthquake even sometimes. In our study we are concerned not only about the absence of seismic-resistant building codes but, in many cases, an absence of any building code.
W: So your title talks about buildings as weapons of mass destruction, but you focus right on a specific part of the globe as being especially high risk.(l)Can you describe the tectonic situation in South Central Asia?
M:(l)The tectonic situation is particularly malicious because many of the earthquakes that occur in this part of the world occur on dry land. That sounds a rather obvious thing to state, but if you think about some of the big earthquakes that have occurred in the last several years, they’ve occurred on plate boundaries. They’ve occurred where there’s an ocean, a seaside, on one side and on the other side you have people.(l)In Southeast Asia, much of it is in a very wide collision zone where the earthquakes are occurring far from the ocean. And, of course, that’s where the people live.
W: Right. You provide some numbers in your perspective about the number of deaths—and I was really stunned over the timescale that you’re able to talk about. Can you share those numbers?
M: Yes. We calculate very roughly about a million people have been killed by earthquakes in the last thousand years. Of course details of the older earthquakes are sometimes a bit doubtful.(2)But the more recent ones have been occurring not in Iran where most of the deaths have historically occurred but in parts of India and Indonesia, Burma, and so on. So there’s been a kind of shift in the fatality counts as a function of longitude. And we were puzzled about this. It could be simply a coincidence, but we can see some underlying reasons. One, of course, is that populations have increased enormously in this part of the world, particularly in India and in Pakistan too.
W: Interesting. So, as you say, there are many poorly built houses in these regions, so they might be expected to be damaged in an earthquake. But in your paper you bring up this point that this is now statistically quantifiable. Can you talk about that?
M: Yes. There are two groups who have focused on attempting to characterize the fatality count within minutes of an earthquake, and it’s done like this.(3)When an earthquake occurs it takes about 20 minutes or 25 minutes for the world seismometers to register that information, but once it’s done it only takes a computer a few seconds to calculate its depth, its magnitude, its position very precisely. And from that information you can get another computer program going that takes information about building fragility, and within 30 seconds of knowing where the earthquake occurred, you can usually predict the number of people killed or injured or even costs due to the damage. This of course is an appalling thing for us to be able to do because people on the ground in these earthquakes have no idea what’s hit them until several weeks have elapsed until the actual numbers come out. Why can we do this? Because we know from the past 10 - 20 years of earthquakes exactly what happens in a built-up urban environment and we know something about the fragility of the buildings there, so we can actually do these calculations. I think this is one of the saddest things that clever seismologists have been able to do, and it’s of course not their fault. It’s entirely something to do with the ethics of building styles, or the construction practices of the countries where these earthquakes occur.
W: But is there anything being done to improve conditions of these buildings or prevent deaths in, say, Iran or in some of these other countries?
M: OK. If I answer that honestly you won’t like it. The bottom line is everyone is really concerned when 5,000 people are killed in a village or a town from an earthquake that wasn’t expected, or was expected and the people will blame each other for why buildings fell down. When an earthquake occurs people are concerned about the deaths, and there is a period of maybe a year before people completely forget about it. And during that year there’s a frenzy of activity to fix buildings, to start retrofitting things, to build new schools. And that’s great.(4)But there’s no attempt to fix the problem in the next village where the next earthquake will occur.
W: Right.(4/5)So basically the science is available to help make the predictions, and you can even use technology to_get the building codes to the right level, but you actually have to have the political will and the infrastructure to build to those codes.
M: Absolutely. There is no point in having a building code if it’s not applied, and this is only too common. You may recall last month the collapse of a factory in Bangladesh? No earthquake. The wind wasn’t blowing. It just fell. And that is appalling. It should never have been committed to be constructed in that way. And, unfortunately, we live in a world where there are many buildings that are just waiting to be shaken a little by quite a modest earthquake and they will collapse. And we’ll only find out about them when they do collapse.
W: Alright. Well, Roger Bilham, thank you so much for talking with me.
M: Thank you.