Earthquake mitigation is a major livelihood project
— awareness-raising on earthquake warning
I. Concepts and rationale for earthquake early warning
Earthquake warning is the rapid estimation of seismic parameters and prediction of the impact on surrounding areas following an earthquake and the release of early warning information on seismic intensity and arrival times prior to the arrival of destructive seismic waves, based on early information from seismic waves observed at seismic stations. For a specific early warning target area, the time lag between the dispatch of early warning messages and the arrival of destructive seismic waves is commonly referred to as the warning time. The more intensive the seismic monitoring stations are and the further away the warning destination from the epicentre, the longer the warning time。
Earthquake warning and seismic forecasting are fundamentally different. Seismic forecasts predict the timing, location and magnitude of future devastating earthquakes through monitoring and research of multiple information, including seismic geology, seismic activity and pre-earthquake anomalies. In other words, seismic forecasts are made before earthquakes occur, while earthquake early warning is made after earthquakes。
Seismic early warning systems use two time differentials to achieve early warning of earthquakes, the time difference between the speed of transmission of two seismic waves and the time difference between the speed of transmission of electromagnetic and seismic waves. The seismic stations close to the epicentre automatically detect vertical waves, which are transmitted rapidly through electromagnetic waves to the data processing centre, and the system rapidly estimates seismic parameters and sends early warning messages of earthquakes before destructive waves reach a certain location。
Application of earthquake early warning information
Early warning information on earthquakes can inform government emergency decision-making. The public could take timely measures to avoid the earthquake and significantly reduce casualties, based on early warning information from earthquakes. Seismic early warning can also provide safety and security services for major works. Major works such as urban gas and power supply systems, nuclear power plants, reservoir dams, large power transformers and pipelines, high-speed railways can initiate corresponding brakes, closures and other disposal systems based on early warning information to mitigate direct seismic and secondary disaster losses。
Iii. Earthquake early warning systems in our city:
My city is located in the earthquake-prone region of my country, and with the acceleration of the urbanization process, important facilities, high-level buildings and infrastructure are on the increase and the damage caused by the earthquake is increasing. In the face of the severe situation, it is particularly important to ensure that, in the event of a severe earthquake, citizens and major projects are protected from emergency risks, that earthquake emergency relief is properly organized and that damage to human life and property is minimized. To this end, our city, in collaboration with the chenghui institute for disaster reduction, has introduced the latest earthquake warning studies, constructed an earthquake warning and high-strength rapid reporting system for the climbing market, installed 38 seismic warning and high-strength monitoring stations in two districts of my city, three districts, and implemented 24-hour real-time monitoring of the climbing flowers and surrounding areas. In the event of an earthquake in the region, the system will react rapidly at the speed of a second-scale response, providing early warning through imagery and sound of the time that destructive seismic waves reach and climb the branch and the possible impact on the climbing of the flower market。
Early warning alerts from early warning centres are now received by downloading the free mobile earthquake forecasting software. For the general public, “earthquake alert” can be downloaded free of charge and registered for trial at 360 mobile assistants, 91 mobile assistants and apple stores. In the state of data flow, if an earthquake occurs, it will tell you in advance how many seconds the seismic wave will reach you。
In the next step, the municipal office for earthquake prevention and mitigation will be actively engaged in the upgrading of seismic monitoring instruments and facilities, the improvement of the earthquake warning and speed reporting system and the gradual expansion of the application of early warning systems。
