Few nations have earthquake early warning systems (Eatyhquake Early Warning, or EEW): Japan, China, Turkey, Romania, Italy, as well as the island of Taiwan, are among them. However, they do not all work in the same way, nor do they have the same scope.
The most advanced is that of Japan, in force since 2007. Located on the Pacific Ring of Fire, the country is prone to earthquakes, like the one in 1923 that left more than 100,000 dead, or the one in 2011, of magnitude 9, that left thousands dead and caused a tsunami and a disaster at the Fukushima nuclear power plant. The Japanese system detects the movements, calculates the epicenter and sends warnings from the thousand seismographs that it has distributed in the country. It is capable of measuring P waves (first, they are the first evidence of an earthquake) and s waves (secondary, the most destructive). It is managed by the National Research Institute for Earth Science and Disaster Prevention, although it is the Agency The Japan Meteorological Authority sends out the warnings, and there are private early warning systems in the country, operating mainly in offices and factories.
Operated by the National Service of Meteorology and Hydrology, it detects earthquakes greater than magnitude 5, on the Shindo scale, or 4.5, on the Richter scale.
Unlike what happens in Mexico, the alerts in Japan come in the form of images with warnings that an earthquake is approaching. They can be via message on the cell phone – the main providers are required to have the application that appears in the form of an image and the sound of bells – on television, or on the radio. Some cable television providers also have a paid service to notify customers. The sound is very different from the Mexican alert. It is designed to try to prevent panic among people.
The system makes it possible to alert, in addition to citizens, nuclear power plants, and even transport systems such as railways or trains, so that they slow down or stop and thus avoid a derailment at the time of the tremor.
The anticipation of the warning, as in other countries with early warning systems, depends on factors such as the distance from the epicenter. The farther away, the more time you have to warn people. In populations located on faults, such as California, it is difficult for alerts to work.
Other nations have shown interest in a system like the Japanese. However, no EEW is cheap, least of all one like the Japanese one, which has nationwide coverage. The government spent a billion dollars on construction alone.
The case of Taiwan
Taiwan, also located in the Pacific Ring of Fire, has a regional system, developed by the Central Climate Bureau, the National Center for High Performance Computing, the Center for Earthquake Engineering Research, and the National Center for Science and Technology. National Technology and Disaster Reduction, at a cost equivalent to one million dollars. It was installed in just over 200 schools, although the goal is to alert the rest of the population. In some cases, in addition to an audible tone, the warning works by flashing LED lights to alert students.
As of 2013, it had 700 strong and 100 real-time earthquake monitoring stations that can issue alerts within 20 seconds of the initial detection of seismic movement. The experts were also working on a project to create low-cost sensors (MEMS).
China, despite not being in the most active seismic zone in the world, like Indonesia, has a regional alert system, through which messages are sent via cell phone. In South Korea, starting in 2016, the alert service began to be developed, via text messages, to citizens, but only in Korean. Then it was thought to make it multilingual, considering events such as the Pyeongchang Winter Olympics.
Many early warning systems are designed to alert nuclear power plants or transportation systems and prevent disasters. This is the case of Turkey, where 100 alcerometers -10 stations- were placed at strategic points in Istanbul, close to the Marmara Fault, which allow a quick map to be drawn up of telluric movements and damage assessment, although they do not calculate the location or the magnitude of earthquakes in real time. The Marmaray Underground Metro, which connects Asia with Europe, uses it to slow down or stop in case of danger. It also works at the Enron Power Plant.
In Romania, where the World Bank (WB) estimated the damage caused by the 1977 earthquake, which left 1,578 dead and tens of thousands of homes destroyed, at 2 billion dollars, the system – managed by the National Institute for Physics of the Earth, and operated by the government, it measures P-type waves. It focuses on the area affected by the Vrancea fault, particularly Bucharest, and allows nuclear installations to be alerted. It also protects the Basarab, one of the largest suspension bridges in Europe.
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