Listen: On The Alert: The Next Generation Of Earthquake Early Warning Systems
"Underground in the San Fernando Valley near Northridge California and earthquake popped magnitude six point seven in depending on who you talk to between ten and twenty seconds that energy from that slip up the faults of deep in the Earth Killed Sixty people injured five thousand knocked out three of the busiest freeways in the United States. And depending on how you count caused fifty billion dollars damage at that time. The costliest natural disaster in the history of the United States I wife and I were in bed and suddenly found ourselves being hurled up and down as the energy of that quake almost instantaneously traveled the fifteen miles from the epicenter out in the Valley to Santa Monica California where we lived at that time. I'm Robert Lee hosts I'm a science writer for the Wall Street Journal so once I realized that equated stopped No broken bones baby good wife. Good dog good gashes off away. You could smell a lot of gas. The thing for me to do was to immediately abandon my wife my baby in my dog and my community Eddie. And of course Fine my way to our newsroom balance the time is four forty three in southern California and it was interesting. The highways had been knocked out. Overpasses that just simply collapsed in the shaking so trying to figure out how to get downtown was tricky a local radio play. A huge role in northridge is kind of voice of sharing information about what had been damaged and what to avoid so I was kind of navigating. FM Radio One right now a little little. Thank goodness we'll let you know what's going on here close. Your instinct is a journalist anyways when in doubt head to the newsroom. So there we all are and I'm feeling quite proud of myself for having fought my way downtown. I'm a real you know. Newspaper Warrior and only later. Did I understand Dan that I had turned my back on one of the hardest hit communities we think of of earthquake is simply consisting of that violent moment when the rocks actually slip but of course this a physics to it. It's like striking Gong like you. Strike a portion of the planet with a really big stick and it resonates it sends off seismic waves in three dimensions. Johnson depending on what the rocks are pending on. How soft the sands are you get all kinds of very local and in surprising and damaging effects the basin of Los Angeles was literally like a bell that Shaped and focused. I these reverberating seismic waves in unexpected ways after the immediate immediate disaster area in the San Fernando Valley itself one of the hardest hit places from the North Ridge. Quake was Santa Monica and if I had only turned around that was running out of the House and getting getting into the car I noticed all of these chimneys have collapsed anything made out of brick and come down the apartment buildings. Most of them were damaged severely in some some way or other literally I lived on the Far Eastern edge of the city and just literally did not turn around after remember at this time. Cell phones are still pretty unusual no broadband internet no special anti earthquake gas. Valves Northridge was a real educational moment. A lot of ways for the California Earthquake Experience From The Wall Street Journal. This is the future of everything. I'm Qatari Yoga. The Northridge Earthquake that shook Los Angeles and our reporter Lee hosts twenty five years years ago was one of the deadliest and most costly in recent. US history and as least said it came without warning no sirens no public alerts on the radio radio just shaking. A similar earthquake had hit Mexico almost a decade earlier on September. Nineteenth Nineteen eighty-five a tremor struck in the early morning hours. It leveled large swath of Mexico City and killed more than six thousand people that earthquake and the deadly aftermath for math triggered a massive response. The Mexican government launched the world's first public earthquake early warning system for years it was a model for other countries including the US but the advent of big data and smartphones has changed how we collect process and distribute information for essential public information like this. It's brought up new questions. How do you build an early warning system for a disaster scientists? Say They can't predict and who should be entrusted to manage them and with what technologies are reporters Yellow Hernandez and Robbie Whelan went looking for answers starting in Mexico City so people have been studying earthquakes in Mexico. For centuries the Aztecs even had their own symbol for them. This is the symbol of earthquake. This what what is called all in old double L. I n.. And it means motion and in there because mommy the Michika cultures which they aspects were part of believed that we were in the fifth world. Previous world's have been destroyed by fire by water by several other things so we're in the era of earthquakes. Which I was saying is that is an ominous is an ominous prediction for those of us who live in Mexico? City that's Harare. Suarez a seismologist colleges at the Institute for Geophysics Mexico City's National Autonomous University. The shelves in his office are filled with maps and books about earthquakes and volcanoes take the bookie showing us has colorful ancient drawings that tell stories about earthquakes. That happened hundreds of years ago before the dawn of modern seismology the title. The book is Louise Most in the history of the earthquakes in the history of Mexico. Mexico is one of the most active regions in the world in terms of earthquakes. These aspects paintings are part art and part data their earlier recordings of where and when tremors hit and scientists reminding these paintings for information to help them understand earthquakes. Happen in the future. This tells them more a more interesting story that when the earthquake occurred there was also apparently volcanic eruption and there was a comment that was on the sky but then below as in all cases we have the all in the x shaped deep to symbol meaning earthquake. But this time it's a different color and there are two layers representing the earth and there has been a lot of speculation collision what that means if it is the size that I prefer Greek or whatever but we really don't have no so. I just put the book together after the Nineteen eighty-five earthquake it. It was an attempt to understand the past data that infamous tremor also signal the parallel shift for science. The earthquake of Nineteen September of nineteen eighty eighty. Five was a breaking point was truly a turning point in in seismological and engineering research in Mexico. GEICO that day sodas was getting ready to take his young son to daycare. Just come back to Mexico after working in New York I felt the earthy and I it was price because it was a very long. My wife could look. This is a major as you know we've lived in the US for too long. Maybe you know we're not used. I worth picks anymore. After the shaking was over he drove to a meeting. He didn't do much damage on the way then someone on the TV so broke gusting over the damage in Mexico and of course there was deadening silence and the meetings over. We might call tonight said you know. I think it's time for us. Go to figure out what happened. That earthquake measured eight point zero the next day a major aftershock hit seven seven point five together. They leveled the city. At least six thousand people were killed. It was a wakeup call for scientists just like Swat is they knew that just measuring the earthquake strength. After the fact wasn't enough anymore they wanted to use data sensors and algorithms to let people know in real all time that it was happening the movement of people to think. Well maybe what if we could install a series of instruments that could detect theoretically classify to see if it was a large earthquake that deserves to be warned and then issue a warning in Mexico City. The city's location and makes it particularly well suited for an earthquake early warning system many of the major earthquakes that hit the Mexican capital come from hundreds of miles to the South West. Where the Cocos and North American tectonic onic plates jam up against each other? It takes about a minute or a minute and a half for the seismic wave to reach the city. That's IT gives the people a window of time to allow for an early warning so the thinking was it was think of denying that is a region that is most dangerous so we should instrument that region. And I I think of were eleven. If I'm not mistaken I've been reliving. Sentencing insurance on the coast. Today there are ninety seven motion sensors mostly along Mexico's Pacific coast from the state of police. Go in the north to Oaxaca in the south some are also located inland south of Mexico City and within six years the system known as Saas Mix was measuring seismic activity and issuing alerts. That makes Mexico's the oldest earthquake early warning system. In the world Japan and Taiwan now operates similar systems but when it began in nineteen ninety one sauce mix was revolutionary since then the system has detected thousands of earthquakes in issued more than one hundred alerts currently only earthquakes larger than five point. Five get get one. The whole thing is automated to avoid human error but even without human error there can be issues warning systems. Don't work as well when earthquakes are close like the earthquake that hit on September nineteenth. Two thousand seventeen. A seven point one magnitude earthquake hit in the early afternoon exactly thirty two years to the day after the infamous nineteen maybe five quake. The epicenter was roughly sixty miles south of Mexico City. The Automated System at series is supposed to send out warnings. Roughly twelve thousand speakers mounted on telephone poles across Mexico City. The system is also supposed to alert residents of earthquakes strong as this one through radio and TV but because the epicenter was so close to the capital there wasn't enough time the shaking and the alerts basically came at the same time and even when there is enough time. There aren't loudspeakers loudspeakers everywhere and some of them don't work. I've slept through several earthquakes in Mexico City and even been surprised by sudden shaking. I was wide awake because I."