News / Asia

    Tsunami Warning Systems: Lessons from Japan

    A screen grab taken from news footage by Japanese Government broadcaster NHK shows cars on a flooded street following the earthquake-triggered tsumani in Miyagi prefecture, March 11, 2011.
    A screen grab taken from news footage by Japanese Government broadcaster NHK shows cars on a flooded street following the earthquake-triggered tsumani in Miyagi prefecture, March 11, 2011.

    Japan is one of the most well-prepared countries in the world to deal with the threat of a tsunami.

    Warning systems are in place, and concrete sea walls wrap around much of the coastline. But nature's wrath on Friday was just too big for the man-made protective measures, raising the question, what went wrong?

    VOA's Kate Woodsome reached out to Costas Synolakis, a tsunami expert with the Department of Civil and Environmental Engineering at the University of Southern California, to find out.

    What went wrong with Japan’s tsunami warning system?

    "Japan is one of those most well-prepared countries on earth in terms of tsunami warning. They had a warning. Clearly what went wrong is they had not anticipated the size of this event. There are two reasons for it. One is that they haven't had any event in even recent memory, the last 100, 150 years, that was anywhere as big as this one.  And two, seismologists and geophysicists hadn't anticipated such a large earthquake happening off Japan. So, on both counts, part of the warning system is essentially to have inundation and flooding maps, and make plans for people. I think that it is that part of the system that failed."

    Forty percent of Japan’s coastline is lined with concrete seawalls. What role did they play in this disaster?

    "The concrete seawalls in many places in Japan are about 10 meters, that's about 33 feet. In Sendai, they were about three meters, that's about 10 feet. So that shows you that at least in that area they were not expecting such a sizeable wave because they would have built a higher seawall. In some ways, the low seawall complicated things, because sure, it's better than nothing, but on the other hand, waves were caught in and quite possibly people were caught in a false sense of security, and emergency managers thought they had sufficient defense, which didn't prove to be the case."

    Should these seawalls be redesigned, be built taller, or is it flawed thinking to say man can hold nature at bay?

    "Well, it's both. I think the new thinking that we're developing worldwide is that we have to build community resilience. This sounds holistic, but in fact it's much more than that. A resilient community to coastal hazards needs to have resilience which means essential redundancies in anything, energy, transportation, water, emergency management, housing, everything. If you overestimate or overinvest in one part of the system, like building coastal defenses, and then you do not invest in the other parts of the system, like backup systems or redundant systems, then, you get what we just saw."

    How fast does a tsunami travel, and how fast, and how far and how high would you have to run to get away from it?

    "The answer depends on what part of the coast you're at. If you're on a coastline that's fairly flat, you have to go fairly far inland, at least three miles, four miles [about five or six kilometers], and if you have about half-an-hour to run, three miles in a half an hour, that's a good jog. Most people wouldn't be able to do that. I think in Japan they have plans for vertical evacuation structures, so people would evacuate to buildings nearby and in some cases they're building special evacuation structures, but most of their defenses and evacuation structures were designed too low, because they were not expecting this size of a wave."

    The National Oceanic and Atmospheric Administration issued a tsunami alert 12 minutes after Japan’s earthquake using a system of sensor buoys.

    "Right. NOAA detects an earthquake with seismographs on Honolulu and in Boulder, Colorado. They make an initial assessment. Then, they have pre-computed scenarios for practically all the earthquakes that can possibly take place around the Pacific Rim, and now they're doing this for the Caribbean and the Indian Ocean. They look at the closest scenario, then they wait up until the tsunami reaches any one of these NOAA buoys. These instruments essentially sit on the seafloor. They are bottom pressure recorders. They record the changes in the water pressure as the tsunami goes by, and then they emit a signal that goes into the buoy, and then from the buoy it goes to a NOAA satellite, and from the satellite, it goes into the warning center.

    NOAA map shows estimated tsunami travel times after Japan's earthquake.
    NOAA map shows estimated tsunami travel times after Japan's earthquake.

    As the tsunami advances across the Pacific, they get new measurements and they update the forecast. And in this case, just like what happened in Chile last year, there was an 8.8 earthquake on February 22, the forecast was right on for practically all the places that we know of around the Pacific. There were no surprises there. The forecast, it worked."

    The tsunami in Japan pushed houses and cars inland. What happens when the water goes out? Are we going to have cars all over the ocean?

    "Generally no, because what happens is a single tsunami is not a single wave, it's a series of waves. So typically what happens is they will move back and forth but generally as they move inland, they will be stuck, and then the next wave is not so big, so it's not going to be able to draw them back. It turns out it's not that difficult to get a car to move. All you need is about less than three feet of water and the car will float. Once it starts floating, typically it will get tangled into debris that's already there, and it will get stuck, it will get overturned a zillion times. Sometimes you have hard time recognizing the brand of the car since you see a skeleton after the tsunami. Mercifully they don't get dragged out to sea so they don't pose any further hazards. They don't do any contamination."

    How can the world better prepare for tsunamis?

    "Well, I am fairly disappointed that almost six years after we've had the Indonesian tsunami, we're still lacking in certain areas. One is public education. Then, around the world as we go around the Pacific, we see failures of the system. For example, in Samoa, people evacuated by car. There were traffic jams and people drowned. The hills were very close. In some cases they were 300 feet [91 meters] away. They could have easily climbed up the hill, 30 feet [nine meters], and would have been safe, versus waiting in a traffic jam to move away from the beach.

    What we saw in Sumatra and Indonesia last October, when there was another tsunami, is that the government relied on these lines that go underneath the TV screens and interrupt the broadcast saying, 'There's a tsunami warning, evacuate.' Well hello, most of the villages at risk, the islands don't have any electricity. They could have had sirens, and they could have been powered by solar generators, solar panels, and they could have communicated with signals like what we have in mobile telephones. But they didn't. They relied exclusively on broadcasting something on TV when most people there don't even have electricity. So it's gaffes like this that just shouldn't happen in this day and age. After we've seen essentially hundreds of thousands of people having died in tsunamis in the last six years, we shouldn't be doing these things. We should be doing much better than this."

    You May Like

    Russia Sees Brexit Impact Widespread but Temporary

    Officials, citizens react to Britain’s vote to exit European Union with mix of pleasure, understanding and concern

    Obama Encourages Entrepreneurs to Seek Global Interconnection

    President tells entrepreneurs at global summit at Stanford University to find mentors, push ahead with new ideas on day after Britain voters decide to exit EU

    Video Some US Gun Owners Support Gun Control

    Defying the stereotype, Dave Makings says he'd give up his assault rifle for a comprehensive program to reduce gun violence

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Brexit Vote Plunges Global Markets Into Unchartered Territoryi
    X
    June 24, 2016 9:38 PM
    British voters plunged global markets into unknown territory after they voted Thursday to leave the European Union. The results of the Brexit vote, the term coined to describe the referendum, caught many off guard. Analysts say the resulting volatility could last for weeks, perhaps longer. Mil Arcega reports.
    Video

    Video Brexit Vote Plunges Global Markets Into Unchartered Territory

    British voters plunged global markets into unknown territory after they voted Thursday to leave the European Union. The results of the Brexit vote, the term coined to describe the referendum, caught many off guard. Analysts say the resulting volatility could last for weeks, perhaps longer. Mil Arcega reports.
    Video

    Video Orlando Shooting Changes Debate on Gun Control

    It’s been nearly two weeks since the largest mass shooting ever in the United States. Despite public calls for tighter gun control laws, Congress is at an impasse. Democratic lawmakers resorted to a 1960s civil rights tactic to portray their frustration. VOA’s Carolyn Presutti explains how the Orlando, Florida shooting is changing the debate.
    Video

    Video Tunisian Fishing Town Searches for Jobs, Local Development Solutions

    As the European Union tries to come to grips with its migrant crisis, some newcomers are leaving voluntarily. But those returning to their home countries face an uncertain future.  Five years after Tunisia's revolution, the tiny North African country is struggling with unrest, soaring unemployment and plummeting growth. From the southern Tunisian fishing town of Zarzis, Lisa Bryant takes a look for VOA at a search for local solutions.
    Video

    Video 'American Troops' in Russia Despite Tensions

    Historic battle re-enactment is a niche hobby with a fair number of adherents in Russia where past military victories are played-up by the Kremlin as a show of national strength. But, one group of World War II re-enactors in Moscow has the rare distinction of choosing to play western ally troops. VOA's Daniel Schearf explains.
    Video

    Video Experts: Very Few Killed in US Gun Violence Are Victims of Mass Shootings

    The deadly shooting at a Florida nightclub has reignited the debate in the U.S. over gun control. Although Congress doesn't provide government health agencies funds to study gun violence, public health experts say private research has helped them learn some things about the issue. VOA's Carol Pearson reports.
    Video

    Video Trump Unleashes Broadside Against Clinton to Try to Ease GOP Doubts

    Recent public opinion polls show Republican Donald Trump slipping behind Democrat Hillary Clinton in the presidential election matchup for November. Trump trails her both in fundraising and campaign organization, but he's intensifying his attacks on the former secretary of state. VOA National Correspondent Jim Malone reports.
    Video

    Video Muslim American Mayor Calls for Tolerance

    Syrian-born Mohamed Khairullah describes himself as "an American mayor who happens to be Muslim." As the three-term mayor of Prospect Park, New Jersey, he believes his town of 6,000 is an example of how ethnicity and religious beliefs should not determine a community's leadership. Ramon Taylor has this report from Prospect Park.
    Video

    Video Internal Rifts Over Syria Policy Could Be Headache for Next US President

    With the Obama administration showing little outward enthusiasm for adopting a more robust Syria policy, there is a strong likelihood that the internal discontent expressed by State Department employees will roll over to the next administration. VOA State Department correspondent Pam Dockins reports.
    Video

    Video Senegal to Park Colorful ‘Cars Rapide’ Permanently

    Brightly painted cars rapide are a hallmark of Dakar, offering residents a cheap way to get around the capital city since 1976. But the privately owned minibuses are scheduled to be parked for good in late 2018, as Ricci Shryock reports for VOA.
    Video

    Video Florida Gets $1 Million in Emergency Government Funding for Orlando

    The U.S. government has granted $1 million in emergency funding to the state of Florida to cover the costs linked to the June 12 massacre in Orlando. U.S. Attorney General Loretta Lynch announced the grant Tuesday in Orlando, where she met with survivors of the shooting attack that killed 49 people. Zlatica Hoke reports.
    Video

    Video How to Print Impossible Shapes with Metal

    3-D printing with metals is rapidly becoming more advanced. As printers become more affordable, the industry is partnering with universities to refine processes for manufacturing previously impossible things. A new 3-D printing lab aims to bring the new technology closer to everyday use. VOA's George Putic reports.
    Video

    Video Big Somali Community in Minnesota Observes Muslim Religious Feast

    Ramadan is widely observed in the north central US state of Minnesota, which a large Muslim community calls home. VOA Somali service reporter Mohmud Masadde files this report from Minneapolis, the state's biggest city.

    Special Report

    Adrift The Invisible African Diaspora