What Have We Learned 10 Years After Sumatra?
Well, quite a bit, but not enough is the short answer. In 2004 we were still laboring under antiquated seismological theories about which subduction zones could and could not produce M9 earthquakes. These theories came from near the dawn of plate tectonics, and had not really been put to the test. Unfortunately, the Sumatra earthquake and later the Tohoku earthquake put an end to the idea that we can actually make such determinations. We can’t. It’s hard for our community to admit this, and many don’t, but I think we have to take a deep breath and accept it, then move on. Will there be a replacement model? I don’t know, but am doubtful that a single model will be able to describe the earthquake behavior of the worlds subduction zones. My gut feeling is that the regional and local geologic context, when added to the commonalities shared by subduction zones, will keep them unpredictable. So perhaps the lesson here is not what we hope it to be, but it’s there just the same. We are hoping for some technical discovery, some new machine or new method that will “solve” the earthquake.tsunami problem decisively. But I think the problem that needs solving is really the way we deal with it. To make earthquakes and tsunami manageable, we need education above all else. From education comes preparedness. From a place of preparedness, we find that prediction is really not that important after all. If we could predict, but were unprepared, how much good would it do? In a few cases, warning helps. Shutting down trains, switching on backup power in emergency rooms, diverting air traffic and that sort of thing, but this comes from short term warning systems which I think have some value. But the value of preparedness is that it doesn’t depend on any new and untested model, nor on any device that may fail in the heat of the moment. Chris Scholz new book Stick-Slip talks a lot about what would happen if we actually had an idea about prediction. The likely reality is more complicated that we might think.
In Japan recently on a project with OPB, we saw again the devastation from 2011. That earthquake/tsunami was in so many ways a success story by comparison to Sumatra. But it’s hard to look around at the towns that are gone, the piles of debris, and meet the people who lost loved ones, children, parents and friends and think this was a success.
So what have we learned, what can we learn? I think we owe it to those who live in the path of great earthquake and tsunami to try, even if success looks like Tohoku. The great test pilots like Bob Hoover, Neil Armstrong and Chuck Yeager say that every street at Edwards Air Force Base is named after one of their friends. Airline safety that we take for granted is because of learning from all the errors that have been made along the way. With what is at stake for the millions that live along subduction zones, can we do less? There was an article today about a new marine science center OSU wants to build in the tsunami zone in Newport Oregon. Vicki McConnell, the State Geologist thinks that really doesn’t make sense and I agree.
Only a few years after the Tohoku tsunami, can we not even learn that simple lesson? I suppose none of the OSU administrators have been to NE Japan lately. If they had, they might have met Mayor Sato of Minami-Sanriku. He was the fellow who famously hung onto the cell antenna on top of the three story public safely building as it went under water (below), drowning most of the 58 member staff. An inspiring man, he feels the weight of responsibility for his town, and the failure of it’s level of preparation. He’s not your ordinary politician, he has his priorities straight.
At the very least, learning from Sumatra (and Tohoku) is simple: don’t build high occupancy buildings in a tsunami zone, particularly when they’re on fill and have limited evacuation options. The people who work there won’t fully understand the risks they are assuming, the engineering will be based on a lot of assumptions, untested, and likely watered down by politics. Mayor Sato knows.