Imagine you are at home eating dinner with your family. You hear your cell phone beep at you with a special ringtone. You hear a siren blare out, "Strong shaking expected in forty seconds. Drop, cover, and hold on." You direct your children to duck underneath the dining table. You open the front door to provide an escape route in the event that the door frame collapses. Your spouse turns off the heat to the stove, and gets out of the kitchen. You then join your children underneath the table. A few seconds later, the ground begins to shake. The ground shifts several feet beneath you, and objects are thrown across the room. In all the chaos, you and your family are safe. Such a hypothetical situation may seem impossible, but technology to warn you and your family before an earthquake's shaking reaches you already is in existence and is being used in some of the most earthquake-prone regions in the world.
In the 1990’s, a commercial group began producing "Quakeguard Seismic Warning Systems." The systems involve a single seismometer placed under a location that detects the harmless, fast moving primary waves of an earthquake. After the P-waves, the slower and more damaging S and Surface waves reach the location. The system alerts the user by setting off an alarm, and sometimes even shutting off the gas supply before the arrival of the damaging Surface waves. Seismic Warning Systems was the first operational version of an earthquake early warning system that was able to alert users tens of seconds ahead of a large earthquake, and has advertised no false positives. The system most recently detected the 4.7 Anza earthquake.
To help clear any confusion, one can envision the situation as follows: an earthquake can be compared to a lightning strike. Once an earthquake is detected, sensors near the epicenter detect the earthquake's fast moving primary waves. The signal sent via the internet, satellite, or other pathway travels at nearly instantaneously to a processing center, and warnings are sent out to those who will be affected. This nearly instantaneous signal can be represented by lightning, while the slower moving secondary and surface waves of the earthquake can be represented by the thunder. As with a lightning strike, the closer you are to the location where the lightning struck (the epicenter of the earthquake), the shorter the interval is between seeing the "lightning" (receiving the warning) and hearing the "thunder" (feeling the earthquake), such that there is no warning that an earthquake is coming.
Also in the 1990's, seismologists in Mexico City created a simple earthquake early warning system that involved seismometers placed on a fault off the coast. When shaking was detected by the seismometers, sirens in the city would sound, giving precious seconds to evacuate un-reinforced buildings, in the region. The system was of great importance due to the fact that Mexico City was built on fill soil that is prone to liquefaction. The system came to be known as Alerta Sismica, and has been expanded over several regions of Mexico.
On January 17, 1995 at 5:46am (Japan Standard Time), a 6.8 magnitude earthquake struck Kobe, the capital of Hyogo Prefecture in Japan. The quake killed over 140,000 people and caused about 100 billion dollars in damages.
Following the quake Japan started work on a nation-wide earthquake early warning system to help save lives in the event of another major earthquake. This system implemented 4,235 seismometers throughout the country to estimate the intensity of an earthquake and to deliver an early warning to all of its users in the affected areas. The system was first implemented to slow down bullet trains and finally, on October 1, 2007, was put into place nationally. It was ready to alert millions through text messages, TV alerts, radio broadcasts, sirens, and government approved earthquake early warning compatible products.
In 2009, Seismic Warning Systems teamed up with government agencies in the Coachella Valley to create the Coachella Valley Regional Earthquake Warning System (CREWS). The system used the 16 "Quakeguard" sensors in the area to create a "network" that will be able to send out warnings of up to 30 seconds to the Valley in the event of a large earthquake near Bombay Beach at the Salton Sea. The system is expected to go live shortly.
Japan's earthquake early warning system proved its usefulness when on March 11, 2011 at 2:46pm (Japan Standard Time); a 9.0 megathrust earthquake struck its coast. Eight seconds after the earthquake began, seismometers offshore Miyagi Prefecture recognized the fastest moving (P) waves of earthquake and immediately sent earthquake early warnings to the Tohoku Region of Japan. Earthquake early warning messages interrupted radio and TV broadcasts automatically. Two sets of computer generated chimes rang, followed by a prerecorded announcement of a man saying the following, “緊急地震速報です。強い揺れに警戒して下さい。 (Kinkyu jishin sokuho desu. Tsuyoi yure ni kekai shite kudasai.)” Translated, the passage reads, “This is an earthquake early warning. Please prepare for powerful tremors.” Although the city of Tokyo received up to a minute of warning time, in Sendai (closest to the epicenter) the warning was only fifteen seconds. Although fifteen seconds may not seem like much time, five seconds is a sufficient amount of time to duck and cover under a sturdy desk. Few people died in the earthquake’s shaking, proving the system’s effectiveness. Unfortunately the tsunami that followed killed 15,845 people with 3,380 people still missing, creating a need for larger seawalls and more efficient tsunami warnings.
Seismologists from Caltech, USGS Pasadena, USGS Menlo Park, and UC Berkeley, have teamed together with the California Integrated Seismic Network to create and perfect an earthquake early warning system for California, and later for the entire United States Pacific Coast. In 2011 a rough earthquake early warning system was created, and is currently being tested by selected seismologists, the Bay Area Rapid Transit System, and other companies and government organizations throughout California.
Seismologists from Caltech, USGS Pasadena, USGS Menlo Park, and UC Berkeley, have teamed together with the California Integrated Seismic Network to create and perfect an earthquake early warning system for California, and later for the entire United States Pacific Coast. In 2011 a rough earthquake early warning system was created, and is currently being tested by selected seismologists, the Bay Area Rapid Transit System, and other companies and government organizations throughout California.
On January 17, 1995 at 5:46am (Japan Standard Time), a 6.8 magnitude earthquake struck Kobe, the capital of Hyogo Prefecture in Japan. The quake killed over 140,000 people and caused about 100 billion dollars in damages.
Following the quake Japan started work on a nation-wide earthquake early warning system to help save lives in the event of another major earthquake. This system implemented 4,235 seismometers throughout the country to estimate the intensity of an earthquake and to deliver an early warning to all of its users in the affected areas. The system was first implemented to slow down bullet trains and finally, on October 1, 2007, was put into place nationally. It was ready to alert millions through text messages, TV alerts, radio broadcasts, sirens, and government approved earthquake early warning compatible products.
In 2009, Seismic Warning Systems teamed up with government agencies in the Coachella Valley to create the Coachella Valley Regional Earthquake Warning System (CREWS). The system used the 16 "Quakeguard" sensors in the area to create a "network" that will be able to send out warnings of up to 30 seconds to the Valley in the event of a large earthquake near Bombay Beach at the Salton Sea. The system is expected to go live shortly.
Japan's earthquake early warning system proved its usefulness when on March 11, 2011 at 2:46pm (Japan Standard Time); a 9.0 megathrust earthquake struck its coast. Eight seconds after the earthquake began, seismometers offshore Miyagi Prefecture recognized the fastest moving (P) waves of earthquake and immediately sent earthquake early warnings to the Tohoku Region of Japan. Earthquake early warning messages interrupted radio and TV broadcasts automatically. Two sets of computer generated chimes rang, followed by a prerecorded announcement of a man saying the following, “緊急地震速報です。強い揺れに警戒して下さい。 (Kinkyu jishin sokuho desu. Tsuyoi yure ni kekai shite kudasai.)” Translated, the passage reads, “This is an earthquake early warning. Please prepare for powerful tremors.” Although the city of Tokyo received up to a minute of warning time, in Sendai (closest to the epicenter) the warning was only fifteen seconds. Although fifteen seconds may not seem like much time, five seconds is a sufficient amount of time to duck and cover under a sturdy desk. Few people died in the earthquake’s shaking, proving the system’s effectiveness. Unfortunately the tsunami that followed killed 15,845 people with 3,380 people still missing, creating a need for larger seawalls and more efficient tsunami warnings.
Seismologists from Caltech, USGS Pasadena, USGS Menlo Park, and UC Berkeley, have teamed together with the California Integrated Seismic Network to create and perfect an earthquake early warning system for California, and later for the entire United States Pacific Coast. In 2011 a rough earthquake early warning system was created, and is currently being tested by selected seismologists, the Bay Area Rapid Transit System, and other companies and government organizations throughout California.
Seismologists from Caltech, USGS Pasadena, USGS Menlo Park, and UC Berkeley, have teamed together with the California Integrated Seismic Network to create and perfect an earthquake early warning system for California, and later for the entire United States Pacific Coast. In 2011 a rough earthquake early warning system was created, and is currently being tested by selected seismologists, the Bay Area Rapid Transit System, and other companies and government organizations throughout California.
Like most functioning systems, there are some issues:
1. Seismometer spacing. There are few seismometers along the Central California and Northern California Coast to detect earthquakes quickly. Seismometer spacing must be reduced to 12 miles apart from each other.
2. Funding. A system along the West Coast would cost approximately one-hundred and fifty-million dollars over five years to perfect, and several million dollars more per year to fund.
On November 29, 2012 the Gordon and Betty Moore Foundation provided a 6 million dollar grant to help fund the earthquake early warning system.
In January 2013, California state senator Alex Padilla proposed a bill to fund a comprehensive state-wide earthquake early warning system.
In April 2013, scientists in USGS Pasadena received five-million-dollars in funding to decrease seismometer spacing and to improve computer programs.
On September 24, 2013, California governor Jerry Brown signed "California State Bill 135" that would create a comprehensive state-wide earthquake early warning system in the state of California. The bill states that the Office of Emergency Services has until January 1, 2016 to determine sources of funding for the system. The bill also "prohibit[s] the office from identifying the General Fund as a funding source to establish the system," meaning the California State Government is unwilling to finance the project. When the system is funded it will take at least several years to broadcast warning messages to the public.
In January 2013, California state senator Alex Padilla proposed a bill to fund a comprehensive state-wide earthquake early warning system.
In April 2013, scientists in USGS Pasadena received five-million-dollars in funding to decrease seismometer spacing and to improve computer programs.
On September 24, 2013, California governor Jerry Brown signed "California State Bill 135" that would create a comprehensive state-wide earthquake early warning system in the state of California. The bill states that the Office of Emergency Services has until January 1, 2016 to determine sources of funding for the system. The bill also "prohibit[s] the office from identifying the General Fund as a funding source to establish the system," meaning the California State Government is unwilling to finance the project. When the system is funded it will take at least several years to broadcast warning messages to the public.
Earthquake early warnings have saved lives in many earthquake prone countries over the past few years. Unfortunately it often takes the loss of thousands of lives to fund such a system. Hopefully, a system will be publicly implemented on the West Coast of the United States without another devastating earthquake to catapult its creation.
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