Yunnan?Province's Zhaotong City was rocked on July 22 by an earthquake measuring 5.1 on the Richter Scale. The jolt, its epicenter in Zhaotong's Yanjin County, claimed 22 lives and drew significant media attention since it was revealed that the quake had been predicted earlier in the month. CCTV's "Law Report" revealed on July 26 that the Yunnan earthquake bureau had stated at the beginning of July a quake would hit the area. The report added that given concerns about the prediction's accuracy, city authorities hesitated to release the information to avoid public anxiety.

Zhaotong's mayor, Luo Yingguang, while speaking to Southern Weekend on August 3, admitted he had received mid-term and long-term seismic analyses prior to the quake. However, he also said that "as a rule, the State Council either releases earthquake forecasts directly or entrusts provincial governments to do so. At no point are municipal and county governments permitted to do so."

"What's more, people with rudimentary seismic knowledge should know that accurate prediction is impossible," he added.

Dai Zhenhua, a Chuncheng Evening News reporter, claimed to have seen the seismic analysis the day after the quake, which stated that: "A magnitude-5.0 quake will possibly occur in northeast Yunnan by the end of this year. The potential seismic area includes Yongshan, Daguan and Yiliang."

After listening to the bureau's report, Zhaotong's Party Secretary Deng Peixian decided to convene a meeting on July 24 to discuss precautionary measures. "Unexpectedly the quake happened before the meeting," Dai sighed.

"Zhaotong's analysis was very helpful," said Huangfu Gang, head of the Yunnan earthquake bureau. "Collating all the information, we then presented to the provincial government a 'short-term prediction', meaning a quake was likely within three months."

"Earthquake prediction is far less accurate than weather forecasting; only one out of ten short-term predictions can be rated as successful," Huangfu noted. "As a result, although an 'imminent forecast' rating has been included in the State Council's regulations, it is beyond our ability to achieve this rating."

"Our analyses and predictions can only remind the local government to keep a lookout for any possible earthquake," he added.

However, circumstances permitting, open information helps to reassure the public in an afflicted area. After the July 22 earthquake, panic swept through Yanjin. To combat the spread of rumors, county head Li Jiang immediately went public with expert opinions on the quake: the seismic origin was nine kilometers deep, the epicenter was 14 kilometers away from the county town, and the biggest aftershock would not measure above 3.0 or 4.0 on the Richter scale.

Meanwhile, experts from China Earthquake Administration (CEA) don't think the Yunnan government should be blamed for "hiding" the quake prediction from the public.

Almost daily, the CEA receives seismic analyses or predictions, claiming a high magnitude quake will occur somewhere. Allowing all these to be publicized would be disastrous, they say.

Last winter's Songhua River pollution incident started an earthquake rumor, leading a large number of Harbin dwellers to stay outside overnight. When SARS ran rampant in 2003, the streets of Anyang in Henan?Province were filled with hundreds of thousands of people, all scared by rumors of an impending quake.

Much praise has been heaped on the successful forecasting of the 7.3-magnitude earthquake in Haicheng, Liaoning?Province in 1975, leading to a grand evacuation three hours prior to the jolt. According to some reports, at least 100,000 residents thus survived the disaster.

Some seismologists claim that the evacuation was merely fortuitous since the warning consisted of sloppy data and insufficient evidence. Allegedly, some portents were observed before the quake allowing the ruling "revolutionary committee" (name for local government at various levels during the 1966-76 Cultural Revolution) to quickly evacuate residents.

At that time, no matter what event it is, political considerations came first, economic losses never being taken into consideration. As CEA experts point out, with a large-scale evacuation of Shanghai causing losses of over 10 billion yuan for example, nowadays the balance might just tip the other way.

A couple of years ago, some foreign seismologists published an article in the Science magazine, claiming it's impossible to make imminent quake forecasts. However, China -- one of the most earthquake-affected countries in the world -- has taken prediction work as a governmental function or task.

Given earthquakes' tendency to be preceded by certain specific factors, densely distributed monitoring situations around seismic sectors, aided with the systematic and detail recording of tectonic plate movement, can make accurate predictions possible on occasion. Examples can be found with the quakes occurring in Xiuyan of Liaoning, Menglan of Yunnan, Jiashi of Xinjiang and Minle of Gansu. Nevertheless, seismic forecasting is still in its infancy stage.

To reduce casualties, experts suggest that the State Council designate key areas in which local governments are required to take precise anti-quake measures. In an emergency, the CEA will use a color code to indicate different levels of seriousness, thus sending early warning signals to the State Council.

(China.org.cn by Shao Da, August 20, 2006)