Receive earthquake early warning information without an App
When the 6.8-magnitude earthquake in Luding occurred, some residents in Sichuan and Chongqing received earthquake early warning information on their mobile phones in advance. One of the early warning screenshots from Chongqing netizens was screened on major websites, "64 seconds later, the seismic waves reached Jiangbei District, Chongqing City. , the epicenter of Luding, Sichuan, with an early warning magnitude of 6.9 and a strong tremor."
For a time, topics such as "Is the earthquake early warning function of your mobile phone turned on?" "It only takes 10 seconds to teach everyone how to turn on the mobile phone earthquake early warning function" quickly filled the hot search.
What is Earthquake Warning?
How does the mobile phone realize the earthquake early warning function?
On September 7, Wang Tun, professor of Sichuan University, director of the Sichuan Provincial Key Laboratory of Earthquake Early Warning and Multi-hazard Early Warning Application Information Technology, and director of the Chengdu High-tech Disaster Reduction Research Institute, made an interpretation.
"Warning" is not "forecast" Many domestic mobile phones have built-in this function
"Earthquake early warning is often confused with earthquake prediction, and the difference between the words is a thousand miles away." Wang Tun said that earthquake prediction is to predict the magnitude, time and location of future earthquakes through research and analysis before an earthquake occurs. .
Earthquake early warning means that after an earthquake occurs, but before the destructive seismic waves reach the target area, an alarm is issued a few seconds or tens of seconds in advance.
How does the mobile phone realize the earthquake early warning function?
Wang Tun said that the Chengdu High-tech Disaster Mitigation Research Institute has intensively installed earthquake early warning monitors in the earthquake area in the early stage. When an earthquake occurs at the epicenter, the monitor uses the principle that electromagnetic waves are faster than seismic waves to obtain and analyze the earthquake early warning monitoring equipment deployed in various places in real time. The data from the station can quickly evaluate the earthquake parameters. If it is found to be a major earthquake, it will issue an early warning to the people around the epicenter in time. Windows and sirens inform earthquake early warning information such as the epicenter, early warning magnitude, early warning time, and estimated intensity," he said.
"During the Luding earthquake with a magnitude of 6.8, the mainland earthquake early warning network jointly built by the Chengdu High-tech Disaster Reduction Research Institute and the China Earthquake Administration successfully issued an earthquake early warning." Wang Tun said that at present, Xiaomi, Huawei, OPPO, vivo and other domestic mobile phones All have access to the earthquake early warning function.
The mobile phone operating system is connected to the earthquake early warning, so that the mobile phone users can enjoy the earthquake early warning function without installing the earthquake early warning app, which solves the problem that it is difficult for the public to download the disaster early warning app.
"The mobile phone operating system level access can also make the earthquake early warning information transmitted according to the highest priority, and minimize the communication delay." Wang Tun said.
The blind spot is smaller and the response is faster. In the future, mobile phones may become earthquake monitoring base stations
Wang Tun said that since 2010, the Chengdu High-tech Disaster Reduction Research Institute has jointly established a continental earthquake early warning network covering 2.4 million square kilometers with the emergency department and the earthquake department, and has successfully warned 73 destructive earthquakes, including a magnitude 7 in Lushan, Sichuan in 2013. Earthquake, the 2017 Jiuzhaigou M7 earthquake, etc.
At present, the system uses the second-generation continental earthquake early warning network, which has a shorter response time, higher reliability, wider coverage, denser stations, and wider service area. The coverage rate of the population in the Sichuan earthquake area has reached 99% .
"The second-generation earthquake early warning technology has made a comprehensive upgrade based on distributed processing for front-end early-warning stations, mid-end transmission response channels, and end-end processing systems. The algorithm is further optimized through the cloud computing operation center, and 5G communication technology can be used to improve System response speed." Wang Tun said that the second-generation early warning network reduces the radius of the early warning blind spot by 15%, and is expected to have a smaller blind spot radius in local areas, and the false alarm rate and false trigger rate are also reduced simultaneously.
In order to further reduce the blind spot of early warning and improve the efficiency of early warning, the Chengdu High-tech Disaster Reduction Research Institute is currently working with domestic mobile phone companies to test the mobile phone earthquake monitoring and early warning function in order to build a mobile phone earthquake monitoring and early warning network.
Wang Tun told reporters that the principle is similar to the traditional earthquake early warning network, but the goal of replacing traditional early warning monitors with built-in sensors in mobile phones is achieved.
"The built-in accelerometer of the smartphone can sense vibration. Once the mobile phone detects the earthquake information, it will send the information to the early warning center server. The early warning center server will combine a lot of mobile phone information to determine whether an earthquake has occurred, and the second level after the determination. Calculate the earthquake early warning magnitude, epicenter location, and earthquake time, and issue early warning information to the affected people around the epicenter." Wang Tun said that in the future, it is hoped that "where there are people, there will be earthquake early warning capabilities."
Wang Tun said that the Chengdu High-tech Disaster Reduction Research Institute is deploying the "sky-air-ground-underground" integrated monitoring and early warning technology for multi-hazard early warning, and will be committed to providing three-dimensional disaster monitoring information, serving natural disaster safety, and serving the government. and emergency management departments.
◎Zou Yunshi and Chen Ke