The Dream And Reality Of Earthquake Prediction
(China Youth Daily) The Dream and Reality of Earthquake Prediction. By Fang Zhouzi. China Youth Daily. May 28, 2008.
When the Wenchuan earthquake occurred on May 12, many people were stunned but also puzzled: Why didn't the Earthquake Administration issue a warning? Were there no precursors for such a large earthquake? There were many doubts, accusations and scorns heaped upon the Earthquake Administration on the Internet. People criticized the Earthquake Administration for being negligent about the earthquake precursor signals, or else they wondered if the Earthquake Administration withheld the warning for the sake of social stability.
People were most familiar with the abnormal animal behavior before the earthquake. A report on May 10, 2008 in Huashi Metropolis Daily" titled "Mass toad immigration in Tanmu village in southwestern Mianzhu" was dug out. According to a May 8 report at the Sichuan Provincial Department of Forestry website, this event occurred on May 5. So this seems a bit too early for an earthquake precursor. In truth, there were also mass toad migrations in Mianzhu in May both last year and the year before. It is not just that the toads in Mianzhu like to move around. The photo usually circulated together with the Mianzhu story was actually taken in Taizhou (Jiangsu province). Recently in Fuzhou and Shenzhen, last May in Tangshan, last September in Linyi, July 2005 in Changchun (Jilin province) ... there were thousands of toads on the move as well. Of course, earthquakes did not occur in those places.
A May 9 report titled "Aba Prefecture Earthquake Preparation Department successfully quelled earthquake rumor" at the Sichuan People's Government website was also discovered and presented as evidence that someone had predicted an earthquake. But that report stated clearly that when the town cadres spoke to the residents about what transpired at a provincial teleconference about preventing geological damage, the dialect accent had the residents mistaking "geological damage" for "earthquake damage" and thus creating a rumor that had to be dispelled.
By coincidence, a 23-year-old Masters student at the Shaanxi Normal University Institute of Tourism published an essay in 2006 in an obscure journal known as the Journal of Castastrophology. After lining up the years during which earthquakes had occurred, the essay concluded that "there may be a magnitude 6.7+ earthquake in the Sichuan-Yunnan area" in 2008. This was regarded by many people as an accurate prediction of the Wenchuan earthquake. But the "Sichuan-Yunnan area" is a vast area and the probability of strong earthquakes there is high (namely, an average of 0.45 earthquake per year). So there is a 45% chance that there would be an earthquake in the Sichuan-Yunnan area each year, never mind the vagueness of "around 2008."
A person who claimed to be a worker at the "Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences" (and that person's name cannot be found in the list of workers at this laboratory) made an Internet post to say that a certain "national treasure" who claimed to have predicted the Tangshan earthquake has also issued a confidential memo on April 30 to the Earthquake Administration in which this earthquake was predicted accurately. But the information was not put to use, and the "natural treasure" could only cry. Since this was "confidential," there was no way for outsiders to know the truth. But the two spokespersons at the Earthquake Administration both denied that the department had received any predictions about the Wenchuan earthquake.
The reason why people hold such high expectations about the Earthquake Administration is due to the common belief that earthquakes can be predicted accurately. This confidence is largely based upon the successful prediction of the 1975 Haicheng earthquake. On the day before that magnitude 7.3 earthquake, the foreshocks were increasing and therefore the government issued a warning. But very few large earthquakes are preceded by foreshocks and small earthquakes do not usually cause large earthquakes. Therefore, that successful prediction can only be said to be a fluke. According to an extensive analysis in the July 2007 issue of the Bulletin of the Seismological Society of America, it had been a combination of confusion, experiential analysis, instinctive judgment and luck." But that instance had caused the Chinese to be misled into thinking that the Earthquake Administration already has the technology to make earthquake predictions. For the tragedy of the Tangshan earthquake next year, people still think that it was because the Earthquake Adminstration was derelict in its duties or even suppressed the prediction made by the "national treasure."
In areas such as Japan and the United States where earthquakes occur frequently, the earthquake departments have never issued earthquake predictions and they have never been criticized as a result. These two countries began to focus on earthquake prediction research in the 1960's, and the seismologists had been full of confidence at first. But two embarrassing things occurred to destroy that confidence.
In the late 1970's, the Japanese seismologists were confident that there would be a magnitude 8 or so "Tokai earthquake" in central Japan. According to the calculations, the Donghai area of Japan experiences a large earthquake once every 120 years. Since this was 120 years since the last earthquake (in 1854), the time was near. Therefore, the Japanese govenrment implemented a series of emergency measures. But the "Tokai earthquake" has yet to occur. Instead, there was a large earthquake in Kobe in 1995 with heavy losses and deaths. From then on, more and more Japanese seismologists realized that it was unrealistic to predict earthquakes. The emphasis for research has shifted to studying the geomechanics of earthquakes, and not earthquake prediction.
In 1979, the US Geological Survey researchers noted that there was a regular periodical cycle for magnitude 5.6 earthquakes in the Parkfield area of California state. The average cycle length was about 22 years. Since the last occurrence was in 1966, the predicted next earthquake should be around 1988. In April 1985, the US Geological Survey issued a prediction that there will be a magnitude 6 earthquake at Parkfield. The seismologists thought that they finally had an opportunity to monitor the entire process of an earthquake. All sorts of instruments were placed in Parkfield, and more than 100 researchers participated in the "Parkfield experiment." Yet, the earthquake that was supposed to happen did not happen. After this incident known as "Waterloo of seismology," American earthquake studies turned towards the study of the geomechanics of earthquakes and the estimation of earthquake prediction. On September 28, 2004, the Parkfield earthquake finally arrived belatedly.
In November 1996, the Assessment of the Prospects for Earthquake Prediction International Conference was held in London. The attendees reached a consensus: Earthquakes cannot be predicted. Not only is this impossible at present, but it won't be possible in the future either. They believe that the Earth is in a state of self-organized criticality, wherein any minor earthquake has the potential of cascading into a large earthquake. This process is highly sensitive and nonlinear with respect to the unknown initial conditions. This makes prediction hard. For example, to predict a large earthquake, it is necessary to know all the physical conditions of the general area (and not just around the tectonic fault). This is impossible. It is also impossible to predict earthquakes from monitoring precursors signs. There are many kinds of these so-called precursors. Different earthquakes often have different precursors. Most of the time, these precursors are "discovered" only after the earthquake, they lack objective definitions, there is no physical theory that links the precursors with the earthquake and there is no statistical proof that such precursors are really related to earthquakes. The majority of these earthquake precursors may be misinterpretations. This makes people wonder if earthquake precursors really exist.
Tokyo University, UCLA and University of Bologna seismologists published an article titled "Earthquakes cannot be predicted" in the March 1997 issue of Science, and this led to a debate. In February and April 1999, many seismologists engaged in a debate at the website of the British journal Nature. There is much disagreement between the two sides, but both sides agreed that it is impossible to make definitive predictions about earthquakes accurately.
Moving into this century, this is still the mainstream view in international seismology. The US Geological Survey states clearly that they do not make earthquake predictions. Instead, they will only make long-term forecasts about the likelihood of an earthquake as well as assessments of earthquake damage. For example, in April this year, the US Geological Survey assessed that the likelihood of a magnitude 6.7 or higher earthquake in the state of California over the next 30 years is 99.7%. But it will not predict the specific time and place of the earthquake.
When modern science is unable to deliver, false science moves into the vacuum. It is not hard to find a market, as is the case with earthquake prediction. According to Richter (who created the Richter earthquake magnitude scale) in 1977: "Journalists and the general public rush to any suggestion of earthquake prediction like hogs toward a full trough... [Prediction] provides a happy hunting ground for amateurs, cranks, and outright publicity-seeking fakers"
For historical and cultural reasons, China has the most number of self-proclaimed "masters" and "national treasures" who can predict earthquakes. They employ an astonishing array of prediction methods: "Taiji series," "Commensurability," "Drought-earthquake association," "Law of Geological Information," "Heaven-earth coupling theory," "Two-time method relating to magnetic storms and lunar phases," ... These people are mostly retired scientists and civilians. When their opinions are not taken seriously by the Earthquake Administration, they say that they are being suppressed; when their opinions are not taken seriously internationally, they blame it on the prejudice of "western science" against "eastern science."
These "masters" usually do not limit their abilities to predicting earthquakes. They claim to be able to use the same methods to predict mountain floods, heavy rainstorms, big landslides, gas explosions in coal mines and other suddenly occurring natural disasters. They usually engage in or support activities that are contrary to modern science (such as studying a perpetual motion machine, opposing the theory of relativity, opposing the theory of evolution, claiming to have proven the Goldbach conjecture, etc).
But their accurate prediction are often done after the fact. When they make a prediction beforehand, they are often very vague and they specify large areas in which earthquakes might occur so that any earthquake in a seismically active area will be included. This creates the wrong impression that they are "very accurate," as in the case of the essay in the Journal of Catastrophology.
Because there are so many "masters" making so many predictions, it is no surprise that someone accurately predicted a certain earthquake by chance. According to the Earthquake Administration workers, they receive more than one hundred earthquake prediction submissions per year. For Beijing, someone or the other is predicting an earthquake for every day of the year. If there should actually be an earthquake in Beijing some day, someone will no doubt be boasting that they had made an accurate prediction beforehand.
Therefore, these types of earthquake predictions are like fortune-telling. One cannot regard someone as a Master for getting it right once. One has to determine the success rates of the predictions. The method of verification is simple. These Masters make their predictions behind closed doors without ever visiting the field to investigate. This means that they can also predict earthquakes in other countries. There is an average of 18 large earthquakes around the world each year. Why not predict the large earthquakes around the world for the next year? See how many they can get right by chance? If they are worried that making an earthquake prediction about China is against the People's Republic of China law on "protecting against and mitigating earthquakes," the law does not say anything about predicting foreign earthquakes.
(Beijing Evening News) Some Questions For Mr. Fang Zhouzi. By Su Wenyang. May 30, 2008.
Mr. Fang Zhouzi regards himself as someone who opposes false science. On the day before yesterday, he wrote a long essay in China Youth Daily against civilian earthquake prediction. I am for science. Therefore, I should be supporting Mr. Fang. But my long-term observation of Mr. Fang is that when he opposes false science, he does not spell out what science itself is. Often, he opposes science in the name of opposing false science. This is another example of that.
The first question to Mr. Fang is whether the Wenchuan disaster is a natural disaster or was it created by false science or rumors? If we agree that this occurred naturally, then we can continue to explore the following.
In Mr. Fang's essay:
When modern science is unable to deliver, false science moves into the vacuum. It is not hard to find a market, as is the case with earthquake prediction. According the Richter (who invented the Richter scale) in 1977: "Reporters and the general public will rush towards any proposal related to earthquake prediction like pigs rushing towards the feed in the trough ... earthquake prediction is a happy hunting paradise for earthquake prediction amateurs, madmen and swindlers."
Mr. Fang seems to have made an elementary self-contradictory error. This is obviously a logical error. Since earthquake prediction is not yet modern science, how can "false science move into the vacuum"?
In Mr. Fang's opinion, false science moves into a vacuum and it has a market. It is one of Mr. Fang's belief that science is a market. Unfortunately, Mr. Fang did not explain whether this was a competitive or monopolized market. The so-called market of "modern science" of Mr. Fang is probably monopolized by Mr. Fang and certain Chinese and foreign experts to the exclusion of everybody else. If you enter the field, you will be tagged with the scary label of "false science."
Can science be monopolized? This is my second question. Modern science cannot predict earthquakes. Not only is it impossible, but according to Mr. Fang, the Japanese and American seismologists published an essay titled "Earthquakes cannot be predicted" in the American journal Science ten years ago. In the 21st century, this is still the mainstream opinion among international seismologists. The mainstream seismologists declared that earthquakes cannot be predicted and anyone who disagrees is a false scientist. Mr. Fang's anti-false-science methods never use science to oppose false science. Instead, he uses the absence of science to oppose scientific exploration and investigation. His absurd logic is like some experts announcing "the prediction of an earthquake at XXX is a rumor" and "there won't be any earthquake in the near future." Since it is the international consensus that earthquakes cannot be predicted, why isn't it just as much of a rumor to say that an earthquake is not going to happen? Haven't they actively spent a lot of time and money to investigate an area that they don't know only to conclude that "it is impossible to predict" and "there won't be any earthquakes." Is it the "journalists and the general public" "rushing like hogs to a full trough" or Mr. Fang and the seismologists who are treating seismology as their own "happy hunting paradise"?
(XYS.org) Teaching Some Logic To <Beijing Evening News> Commentary Section Director Su Wenyang.
<Beijing Evening News> published an essay signed by Su Wenyang who brazenly thinks that he knows more science than anyone else. He hectored me for "not knowing what is science and therefore often opposing science in the name of opposing false science." ...
In the first instance, Director Su said that I "committed an elementary self-contradictory error, which is an obviously logical error." He asked, "Since earthquake prediction is not modern science, then how can 'false science move into the vacuum'?" The answer is: Precisely because modern science is unable to predict earthquakes but people are hoping for earthquakes to be predictable, false science emerges to mislead people. A three-year-old child can understand this simple logical relationship, but the very scientifically learned Director Su cannot. So let me give an example that a one- or two-year child can understand. Presently, modern science cannot rejuvenate people. But there are plenty of marketing slogans in the Beijing market for health medicines and supplements that restore people to youth (you can find those advertisements in <Beijing Evening News>). Isn't this a case of false science entering a vacuum? ...
In the second instance, Director Su asked: "Since it is accepted internationally that earthquakes cannot be predicted, then to predict an earthquake is to create a rumor which is just as much a rumor as predicting that there won't be an earthquake." The answer is: Predicting the occurrence of an earthquake and predicting that an earthquake won't occur are questions of different natures. Science is unable to predict the occurrence of an earthquake. But science also has some understanding about why earthquakes occur. For example, we know that large earthquakes only happen in earthquake zone so we can categorically say that there won't be any large earthquakes outside the earthquake zone. Even inside an earthquake zone, we can dispel the rumor since we know that earthquakes cannot be predicted accurately, then any claim that there shall be an earthquake at a certain place at a certain time is a rumor. This is a logical relationship that even a three-year-old child should know, but Director Su does not. ...
In the third instance, Director Su asked: "Haven't they actively spent a lot of time and money to investigate an area that they don't know only to conclude that "it is impossible to predict" and "there won't be any earthquakes." Is it the "reporters and the general public" "rushing towards the feed in the trough" or Mr. Fang and the seismologists who are treating seismology as their own "happy hunting paradise"?" Does Director Su mean that there always ought to be a positive concluding as a result of spending the large sum of money on research? So when the biologists and medical scientists spend vast amounts of research money, they are not allowed to say that there is no cure for AIDS yet? ...
(The National) The science is still shaky. Robert Matthews. May 19, 2008.
After the devastation of last week’s earthquake in China came the rumours: that it had brought dams to the brink of collapse, caused lethal chemical spills – and was karmic punishment for the mistreatment of Tibet.
Yet one rumour had been doing the rounds even before the quake struck: that Chinese scientists had predicted disaster over a week earlier, but their warning had been suppressed by officials.
Reports of “evil omens” appear to have been circulating for weeks: towns finding themselves overwhelmed with vast numbers of toads, and water mysteriously vanishing from a lake. Such reports often emerge after a disaster as people try to make sense of the appalling events that have overwhelmed them. And they are usually dismissed as superstitious nonsense by scientists, though some – like claims that wild animals somehow sensed the Indian Ocean tsunami before it struck in December 2004 – may have some basis in fact.
But reports of hard-nosed geophysicists being told to keep quiet about telltale “precursors” of last week’s huge quake are a different matter. Is it really possible to predict earthquakes with any reliability, and if so why would anyone want to suppress such predictions?
Scientists have been attempting to find ways of predicting when and where earthquakes will strike for over a century. Their quest has led them to look at everything from emissions of radioactive radon gas to the howling of dogs. And, occasionally, they appear to have succeeded.
On Feb 3, 1975 a swarm of small quakes struck Haicheng Province in Manchuria. Believing them to be precursors of some far more serious event, Chinese geophysicists issued a warning that a major quake would strike within the next two days. Sure enough, less than 24 hours later a major quake did strike, registering 7.3 on the Richter scale — but not before an evacuation had been carried out, allowing thousands of lives to be saved.
It was the first successful prediction of a major quake ever made. Or was it? To this day, the events surrounding the Haicheng earthquake prediction are surrounded by controversy, with sceptics claiming it was little more than a coincidence. Their argument draws strength from the fact that the same Chinese team had made a prediction some months earlier, based on the same type of precursor — but that quake had failed to materialise. And whatever the supposed breakthrough made by the team, it tragically failed to save the lives of the 240,000 who died in the devastating Tang Shan earthquake the following year.
Ever since, various teams of scientists have claimed to have identified reliable precursors of earthquakes – only to have sceptics respond that the resulting predictions owe more to vague definitions of what counts as a “hit” or a “miss” than to solid science. After all, it does not require a PhD in geophysics to predict that China will suffer another devastating quake some time within the next century.
It is now generally agreed that an earthquake prediction must at least give the location and likely magnitude of the event with reasonable precision – together with enough warning to get those affected to safety. But to be taken seriously scientifically, it must do more than that. The precursor must be based on sound geophysical science, and perform significantly better than random chance.
So far, the closest to such a precursor are so-called P-waves. As one of the classic forms of shock wave associated with quakes, there is no doubting their ability to forewarn of devastation. But as they travel at speeds of up to 8km per second, they typically give less than a minute’s warning of the upheaval to follow. As such, what P-waves provide is less a prediction than “pre-detection” of earthquakes. Even so, the governments of Japan, Taiwan and Mexico have all decided even a few seconds warning are worth having. In 2004, a P-wave detection system in Japan gave three seconds warning of a quake, which was enough to allow the famous Bullet Trains to be halted.
But could more useful precursors one day be found? After over a century of failure, many geophysicists believe not – and point to a discovery made over 40 years ago by the American geophysicist Charles Richter, that most grimly familiar name in earthquake science.
Along with his colleague Beno Gutenberg, in 1956 Richter published a “Law of Earthquake Violence” showing that the more violent a quake is, the less likely it is to occur. More precisely, for each extra Richter magnitude, the number of quakes of even greater violence falls by a factor of around 10.
Scientists have since discovered the same kind of law at work in other natural phenomena, including avalanches in piles of sand. And what they have in common is so-called “self-organised criticality” (SOC). Put simply, this means they reach a critical state and then, like a collapsing sand-pile, suddenly rearrange themselves — “self-organise” — into a more stable state.
The existence of the Richter-Gutenberg law thus suggests that in quake zones the Earth’s crust is in an SOC state, with the merest disturbance triggering a catastrophic release of energy as it reaches a more stable state.
If this is so — and several other lines of evidence point to the same conclusion — then the whole idea of quake prediction in its everyday sense is doomed. For it means that a small tremor could turn into a small quake, or a massive one: there is no way of telling. That, in turn, means that any sign of a quake developing is likely to prove hopelessly unreliable, with most “predictions” turning out to be false alarms.
This might explain why – if the rumour is true – the Chinese authorities rejected the supposed prediction of last week’s quake. After a century of failure, false alarms and misplaced hopes, they are rightly sceptical about such predictions.
Most geophysicists would agree that the authorities should focus instead on making homes, schools and dams as resistant as possible to the one prediction that can be made with absolute confidence: last week’s earthquake won’t be the last.