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After a 7.0-magnitude earthquake jolted Lushan County in Ya’an City in southwest China’s Sichuan Province on April 20， a man in distant Heze City， Shandong Province， rose to instant Internet fame. He was dubbed“the king of prophets” after netizens discovered that he successfully predicted the earthquake in Lushan one month before it hit.
The name of the man’s microblog account means “ancestor of earthquake deciphering.” He wrote on March 26， “On the evening of March 19， a tornado hit Daoxian County， Yongzhou City in Hunan Province. Look！ About 30 days later， an earthquake measuring at least 7.0-magnitude will strike to the northwest of the spot where the tornado disappeared.”
It turned out that a 7.0-magtitude did occur about 30 days later， in Lushan County， which lies to the northwest of Daoxian County.
In the last five years， China has been hit by several damaging earthquakes including the devastating 8.0-magnitude Wenchuan earthquake that resulted in 69，227 confirmed deaths in May 2008.
As people survey damage in the aftermath of earthquakes， many cannot help wondering whether they can be predicted. Some looked retrospectively for phenomena that could have offered a warning， hoping to gain the ability to predict future quakes.
Unreliable prediction
Unfortunately， earthquake predictions are often found to be without merit. On April 24， official media People’s Daily listed 10 big rumors about the earthquake in Lushan， among them， the anonymous Heze resident’s prediction.
Netizens disclosed that the so-called “king of prophets” has predicted more than 1，500 earthquakes， but only five occurred.
Usually， non-governmental earthquake predictors make frequent prognostications， most of which are wrong， whereas “only the one that is correct is ever talked about，” said Chen Huizhong， a research fellow with the Institute of Earthquake Science under the China Earthquake Administration （CEA）.
“So far， no one has made an accurate imminent earthquake prediction. This is a difficult scientific issue confronting humankind，” Chen said. “Non-governmental predictors usually give a time range of days or months and talk about a large geographical areas. Given that seismic disturbances of various magnitudes happen quite frequently， they are likely to make correct predictions by luck.”
Now， scientists try to detect earthquakes by monitoring seismic noises and ultra-low magnetic waves， which require large amounts of equipment and data processing. In recent years， experts in the field mostly predicted earthquakes by way of experience and consultation. In this way， the likelihood of a correct prediction is 30 percent at best， and zero at worst， according to Chen.
As for predictions by NGOs or individuals， Chen said that if predictors are confident in their forecasts， they can report to the CEA. The administration will hold consultations and report to higher levels of the government， which will decide whether to announce the prediction.
Sun Shihong， a research fellow with the China Earthquake Networks Center told China Youth Daily that relevant government organizations can refer to or even adopt some of the methods used by non-governmental predictors.
“The non-governmental sector should be encouraged to explore these areas，” Sun said.
Controversial prediction
The mostly widely reported official prediction of an imminent earthquake was made prior to the 7.3-magnitude earthquake that hit Haicheng City in northeast China’s Liaoning Province on February 4， 1975. Yet until today， whether the prediction was successful is still questionable. In 1972， three years before the Haicheng earthquake， Geng Guoqing， then a seismological researcher in Beijing， predicted that there would be devastating earthquakes in three areas in north China， namely， south Liaoning Province， Luanxian County in Tangshan City in Hebei Province， and the vicinity of Hebei’s Shijiazhuang City， Xingtai City and Yixian County.
Geng’s prediction was based on his study of the 69 earthquakes measuring 6.0 on the Richter scale and above that took place in north China and the Bohai Sea areas over the previous 2，202 years of history.
He found that between one and 3.5 years before 67 （97.1 percent） of the 69 earthquakes， there were severe droughts in the region.
In the three or four years after 1972， earthquakes rocked the first two of the three areas Geng mentioned. They were the 7.3-magnitude Haicheng earthquake in 1975 and the 7.8-magnitude Tangshan earthquake in 1976 that killed about 240，000 people.
Months before the Haicheng earthquake， abnormal animal behavior had been observed. It was reported that in December 1974 in southern Liaoning Province， snakes awoke from hibernation and froze to death after leaving their caves. Butterflies and ants， which could not be seen in the area in winter， also appeared on streets. Water in some villages’ wells surged and ebbed abnormally. On February 3， 1975， one day before the major shock hit the area， Haicheng’s local seismographic observatory recorded frequent foreshocks and reported abnormalities to the provincial government.
On the morning of February 4， the Liaoning Provincial Government issued an earthquake warning， and ordered residents to evacuate.
At 4 p.m. that day， Jiang Chentian， a staff member at the seismographic observatory produced a written report， predicting that an earthquake above 5.0-magnitude would strike the area between 7 and 8 p.m. Jiang made the prediction based on his experience in observing instruments measuring telluric electricity. He found an association between abnormal telluric currents and earthquakes.
At 7：36 p.m.， the 7.3-magnitude earthquake struck Haicheng， affecting 8.3 million people in the densely populated industrial area and causing 1，328 deaths. According to Beijing-based Outlook Weekly magazine， without prediction and evacuation， the earthquake would have left a death toll of at least 100，000.
Although the evacuation saved lives， experts disagree on the validity of the prediction.
Li Ping， an academician with the Chinese Academy of Engineering Sciences and a research fellow with the CEA’s Institute of Geology， said that some phenomena observed before the Haicheng earthquake were not recorded in other earthquakes. For instance， he said， the frequent foreshocks preceding the Haicheng earthquake did not occur before the Tangshan earthquake.
In addition， Li said that the Haicheng earthquake was predicted on the basis of earth deformation measurement， yet research found that measurements fell within the margin of error and hence could not serve as grounds for earthquake prediction.
The lack of precision presents a dilemma of whether such predictions should be released to the public.
There are two fundamental questions about earthquake prediction， namely， whether earthquakes can be predicted and whether predictions should be reported， said Mei Shirong， founding Director of the former Earthquake Analysis and Prediction Center， which is now known as the Institute of Earthquake Science， under the CEA. Mei has been blamed by some people for failing to predict the devastating Tangshan earthquake.
Earthquake prediction can cause public panic and even turmoil. Zhang Zhaocheng， a research fellow with the CEA’s Institute of Earthquake Science said that three months before the two 7.2-magnitude earthquakes that struck Sichuan Province’s Songpan and Pingwu counties in August 1976， the Sichuan Seismological Bureau released an earthquake prediction based on a large number of earthquake indicators. Local social order was seriously disrupted. Sixty-one people in a village even committed suicide by drowning， according to Guangdong-based Southcn.com.
Alarm system
Given the difficulty of accurately predicting imminent individual earthquakes， seismologists are seeking alternatives to reduce the potential damage of future earthquakes， including developing earthquake alarm systems.
The Institute of Care-life， a non-governmental research institution in Chengdu， Sichuan， is known for developing an earthquake alarm system.
After the 7.0-magnitude earthquake hit Lushan County on April 20， the system produced alerts via local television networks， the Internet and school broadcasting terminals to neighboring areas， giving Ya’an City 5 seconds of warning and Chengdu City 28 seconds， said Wang Dun， the institute’s Director.
Wang said that the system takes advantage of the time lag between non-destructive P waves and destructive S waves emitted from the hypocenter during an earthquake. Since P waves travel faster than S waves， after sensors detect P waves， warning can be sent out before S waves reach the surface.
The system is expected to give people time to evacuate or find shelter， and time to shut off power and gas supply systems and public transit systems.
The early warning system of the Institute of Care-life was officially put into operation in May 2012. It has covered 400，000 square km of land in eight provinces in southwest and northwest China.
Wang said that theoretical research demonstrates that 3 seconds of warning time can reduce casualties by 14 percent， and 20 seconds of warning time can reduce casualties by 63 percent.
The name of the man’s microblog account means “ancestor of earthquake deciphering.” He wrote on March 26， “On the evening of March 19， a tornado hit Daoxian County， Yongzhou City in Hunan Province. Look！ About 30 days later， an earthquake measuring at least 7.0-magnitude will strike to the northwest of the spot where the tornado disappeared.”
It turned out that a 7.0-magtitude did occur about 30 days later， in Lushan County， which lies to the northwest of Daoxian County.
In the last five years， China has been hit by several damaging earthquakes including the devastating 8.0-magnitude Wenchuan earthquake that resulted in 69，227 confirmed deaths in May 2008.
As people survey damage in the aftermath of earthquakes， many cannot help wondering whether they can be predicted. Some looked retrospectively for phenomena that could have offered a warning， hoping to gain the ability to predict future quakes.
Unreliable prediction
Unfortunately， earthquake predictions are often found to be without merit. On April 24， official media People’s Daily listed 10 big rumors about the earthquake in Lushan， among them， the anonymous Heze resident’s prediction.
Netizens disclosed that the so-called “king of prophets” has predicted more than 1，500 earthquakes， but only five occurred.
Usually， non-governmental earthquake predictors make frequent prognostications， most of which are wrong， whereas “only the one that is correct is ever talked about，” said Chen Huizhong， a research fellow with the Institute of Earthquake Science under the China Earthquake Administration （CEA）.
“So far， no one has made an accurate imminent earthquake prediction. This is a difficult scientific issue confronting humankind，” Chen said. “Non-governmental predictors usually give a time range of days or months and talk about a large geographical areas. Given that seismic disturbances of various magnitudes happen quite frequently， they are likely to make correct predictions by luck.”
Now， scientists try to detect earthquakes by monitoring seismic noises and ultra-low magnetic waves， which require large amounts of equipment and data processing. In recent years， experts in the field mostly predicted earthquakes by way of experience and consultation. In this way， the likelihood of a correct prediction is 30 percent at best， and zero at worst， according to Chen.
As for predictions by NGOs or individuals， Chen said that if predictors are confident in their forecasts， they can report to the CEA. The administration will hold consultations and report to higher levels of the government， which will decide whether to announce the prediction.
Sun Shihong， a research fellow with the China Earthquake Networks Center told China Youth Daily that relevant government organizations can refer to or even adopt some of the methods used by non-governmental predictors.
“The non-governmental sector should be encouraged to explore these areas，” Sun said.
Controversial prediction
The mostly widely reported official prediction of an imminent earthquake was made prior to the 7.3-magnitude earthquake that hit Haicheng City in northeast China’s Liaoning Province on February 4， 1975. Yet until today， whether the prediction was successful is still questionable. In 1972， three years before the Haicheng earthquake， Geng Guoqing， then a seismological researcher in Beijing， predicted that there would be devastating earthquakes in three areas in north China， namely， south Liaoning Province， Luanxian County in Tangshan City in Hebei Province， and the vicinity of Hebei’s Shijiazhuang City， Xingtai City and Yixian County.
Geng’s prediction was based on his study of the 69 earthquakes measuring 6.0 on the Richter scale and above that took place in north China and the Bohai Sea areas over the previous 2，202 years of history.
He found that between one and 3.5 years before 67 （97.1 percent） of the 69 earthquakes， there were severe droughts in the region.
In the three or four years after 1972， earthquakes rocked the first two of the three areas Geng mentioned. They were the 7.3-magnitude Haicheng earthquake in 1975 and the 7.8-magnitude Tangshan earthquake in 1976 that killed about 240，000 people.
Months before the Haicheng earthquake， abnormal animal behavior had been observed. It was reported that in December 1974 in southern Liaoning Province， snakes awoke from hibernation and froze to death after leaving their caves. Butterflies and ants， which could not be seen in the area in winter， also appeared on streets. Water in some villages’ wells surged and ebbed abnormally. On February 3， 1975， one day before the major shock hit the area， Haicheng’s local seismographic observatory recorded frequent foreshocks and reported abnormalities to the provincial government.
On the morning of February 4， the Liaoning Provincial Government issued an earthquake warning， and ordered residents to evacuate.
At 4 p.m. that day， Jiang Chentian， a staff member at the seismographic observatory produced a written report， predicting that an earthquake above 5.0-magnitude would strike the area between 7 and 8 p.m. Jiang made the prediction based on his experience in observing instruments measuring telluric electricity. He found an association between abnormal telluric currents and earthquakes.
At 7：36 p.m.， the 7.3-magnitude earthquake struck Haicheng， affecting 8.3 million people in the densely populated industrial area and causing 1，328 deaths. According to Beijing-based Outlook Weekly magazine， without prediction and evacuation， the earthquake would have left a death toll of at least 100，000.
Although the evacuation saved lives， experts disagree on the validity of the prediction.
Li Ping， an academician with the Chinese Academy of Engineering Sciences and a research fellow with the CEA’s Institute of Geology， said that some phenomena observed before the Haicheng earthquake were not recorded in other earthquakes. For instance， he said， the frequent foreshocks preceding the Haicheng earthquake did not occur before the Tangshan earthquake.
In addition， Li said that the Haicheng earthquake was predicted on the basis of earth deformation measurement， yet research found that measurements fell within the margin of error and hence could not serve as grounds for earthquake prediction.
The lack of precision presents a dilemma of whether such predictions should be released to the public.
There are two fundamental questions about earthquake prediction， namely， whether earthquakes can be predicted and whether predictions should be reported， said Mei Shirong， founding Director of the former Earthquake Analysis and Prediction Center， which is now known as the Institute of Earthquake Science， under the CEA. Mei has been blamed by some people for failing to predict the devastating Tangshan earthquake.
Earthquake prediction can cause public panic and even turmoil. Zhang Zhaocheng， a research fellow with the CEA’s Institute of Earthquake Science said that three months before the two 7.2-magnitude earthquakes that struck Sichuan Province’s Songpan and Pingwu counties in August 1976， the Sichuan Seismological Bureau released an earthquake prediction based on a large number of earthquake indicators. Local social order was seriously disrupted. Sixty-one people in a village even committed suicide by drowning， according to Guangdong-based Southcn.com.
Alarm system
Given the difficulty of accurately predicting imminent individual earthquakes， seismologists are seeking alternatives to reduce the potential damage of future earthquakes， including developing earthquake alarm systems.
The Institute of Care-life， a non-governmental research institution in Chengdu， Sichuan， is known for developing an earthquake alarm system.
After the 7.0-magnitude earthquake hit Lushan County on April 20， the system produced alerts via local television networks， the Internet and school broadcasting terminals to neighboring areas， giving Ya’an City 5 seconds of warning and Chengdu City 28 seconds， said Wang Dun， the institute’s Director.
Wang said that the system takes advantage of the time lag between non-destructive P waves and destructive S waves emitted from the hypocenter during an earthquake. Since P waves travel faster than S waves， after sensors detect P waves， warning can be sent out before S waves reach the surface.
The system is expected to give people time to evacuate or find shelter， and time to shut off power and gas supply systems and public transit systems.
The early warning system of the Institute of Care-life was officially put into operation in May 2012. It has covered 400，000 square km of land in eight provinces in southwest and northwest China.
Wang said that theoretical research demonstrates that 3 seconds of warning time can reduce casualties by 14 percent， and 20 seconds of warning time can reduce casualties by 63 percent.