No one can predict earthquakes as perfectly as hurricanes or floods, but the next big thing you can expect is Early Earthquake Warning System (EEWS). They don't anticipate shaking but react quickly, so warnings may be issued before the first shaking occurs. Faster moving P-wave power can be used to assess the epicenter and magnitude of an earthquake before the more hazardous and harmful surface waves. The trick is to identify P-waves accurately without wolf crying. The longer the time gap between P-waves arriving and the surface waves, the more time is necessary in cases of severe earthquakes for critical response. The time spacing is long for teleseisms (earthquakes far away) but is very short for the local earthquakes.
P-waves can easily be identified when passing a seismometer grid at the ground in a pattern that is somewhat similar to the way in which geophones are used in the oil industry. The origin of the P-waves, including the calculation of arrival times of the first harmful surface waves, can be fixed using a computer system. Then a likely intensity of ground shaking can be calculated, and an emergency alert can be sent.
Basics of EEW System
A breaking fault sends out various wave kinds during an earthquake. The rapidly-moving P-waves come first, but the slower S-waves and later arriving surface waves do damage.
Sensors immediately detect the P-wave and transmit information instantly to an earthquake warning center.
A message from the warning center then is transferred instantly to the mobile phone or computer, calculating the anticipated shaking intensity.
The warning level depends on the speed of the EEW system and the distance between the community that receives the alert and earthquake's epicenter. Depending on the range between the origin of the quake, it can differ from a few seconds to a minute or more.
It may or may not look like the same, but in those few seconds, individuals can find a safe place underneath a table, for instance, or leave the building. Workers may have the opportunity to move hazardous machinery or materials, and medical procedures may be halted before they harm the patient. Even the shortest warning can prevent many injuries and fatalities.
The system allows trains to slow or stop, reduce derailment risk and can safely stop taxiing aircraft. As well as lowering the speed of vehicles, bridges and tunnels can also be prevented from being imprisoned by rock-slides. Emergency services can start reacting; for instance, fire stations can open their garage doors before they fail authority or are affected by structural distortions.
An automated system can be triggered in a few seconds' notifications to prevent damage and loss. The shutdown of industrial procedures and systems or manufacturing lines can reduce company disruption after the warning. For safe operation of nuclear power stations, this is especially important. Cascading failures can sometimes also be prevented by isolating systems, such as reducing the number of fires after the earthquake.
Countries with Early Warning System
Since 2007, Japan has been running the only nationwide early warning system. Some other countries such as Mexico, Turkey, Romania, Taiwan, and Italy are currently developing an early warning system. And it's been more than a couple of years since then California has been developing its own system, which has been tested by Shake Alert on the west coast of the United States. The Geological Survey of the United States has just given Shake Alert designers USD 4 million to put into operation and develop the EEW system as soon as possible. EEW systems are primarily designed to save a life. The biggest challenge is to operate a reliable system in quite a few locations before any big earthquake strike.