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Weather forecasters' dilemma

by Xu Mu

The Hong Kong Observatory building has been standing in the heart of Tsim Sha Tsui for more than 120 years and its work is still highly influential in the everyday dynamics of people's life. Under the critical eyes of the public, it is usually the target of blame when chaos arise because of changing weather conditions.

The timing of issuing warning signals is often critical. It is especially so during peak hours of transport.

“We have decision-making guidelines on issuing warning signals. Generally
speaking, we work according to the scientific basis,” said Yeung Kai-hing, assistant director of the Observatory.

“Of course, the priority is to ensure the personal safety of Hong Kong people.”

Mr Yeung pointed out that if the Observatory considered too many factors, they would find that some factors were contradictory.

“While some factors favour the decision of issuing signals earlier, the others are just in the contrary. In that case, we are not able to make a decision from all those perspectives. Therefore, we have to decide upon some comparatively objective criteria,” Mr Yeung told Varsity in an interview.

Facing the South China Sea , Hong Kong is extremely vulnerable to different kinds of weather hazards caused by the monsoon climate. Though Hong Kong people are used to extreme weather conditions, such as typhoons and heavy rainfalls, they do not want their lives to be paralysed by the poor timing of issuing warning signals.

As extreme weather conditions may result in casualties and disruptions to transport and many other services, warning signals are intended to help people make necessary precautions. Yet, it is always the warning signals that cause the disruption in the first place.

According to the labour guidelines in Hong Kong , employees are not required to go to work when a black rainstorm warning or typhoon signal No. 8 or above is issued. Public transport will be ceased to operate within a few hours after those signals are in effect.

The Observatory often faces the dilemma of timing. If the signals are released during rush hours, they would bring upon much inconvenience to people's lives.

Mr Yeung admitted that there were situations in which the timing of issuing signals had created some traffic chaos, especially when people were travelling to work or back home.

In the current system of tropical cyclone warning, definitions of various signals seem to bear no changes over decades since the system was in place in the 1970s.

Mr Yeung explained that the system could not be changed so often as they had to take into consideration that people needed time to familiarise themselves with all the signals.

In response to the seemingly outdated warning system, Mr Yeung said: “In specific operations, we make necessary adaptations or changes quite frequently to fit the situations.”

“To prevent potential chaos, a forehand signal is issued two hours before the
formal cyclone warning signal is released,” he said.

This system has been working for a few years now. Such a signal can inform people of a pending tropical cyclone and enable them to take preventive measures.

“In the field of providing weather service, we have reached the advanced level of international standard,” Mr Yeung asserted. “More specifically, in the field of providing forecasts on aviation weather, we are of the top level.”

In a survey conducted by the Observatory earlier this year about its services, respondents considered that the weather forecasts in general were 79.9 per cent accurate. But the Observatory itself claims that the accuracy rate could be up to 90 per cent.

The survey result, however, cannot save the Observatory from being blamed during weather hazards, especially those brought upon serious damage or even casualties.

On May 9, 2005 , a sudden squall at the speed of 135 kilometres per hour hit the container terminals in Kwai Chung. Some tacked-up containers tumbled down, and one man was killed.

Lam Chiu-ying, director of the Observatory, did not consider the unexpected squall being the single factor in the accident.

In his lecture delivered to the Executive Council of the World Meteorological Organisation in Geneva on June 30, 2005 , Mr Lam pointed out that many containers, which were properly stacked, remained intact after the squall.

Mr Lam said it was wrong to just blame the weather condition and make meteorologists as scapegoats.

While the director noted the human factor being neglected in causing the hazards, Mr Yeung admitted that the Observatory might make errors sometimes.

“We know that our forecast could sometimes be inaccurate,” Mr Yeung said.

“However, it does not mean that we would leave it that way. Compared with the past, our accuracy has improved through years of progress.

“After listening to the criticisms, of course, we will think about what leads to the inaccuracy.” Mr Yeung acknowledged the fact that even the best equipment on earth could not guarantee an absolutely accurate weather forecast.

“The weather condition is determined by God. We cannot decide it. So we, to some extent, admit our destiny. However, we will still try our best to forecast the weather more accurately,” said Mr Yeung.

The Observatory also understands the importance of communication with the
public. One of its missions is to “embrace partners and share ideas”. To listen to criticisms and advice, the Observatory cooperates with survey companies every year to conduct two telephone polls about their service quality. It also makes an effort to interact with the public.

“We release more than 50 news reports and hold nearly 10 news conferences every year. While we disseminate basic weather information every day, from time to time, we also tell the public about our improvements in providing services,” Mr Yeung said.

He added: “All kinds of lectures we gave received extraordinarily warm welcome, including the lecture on tsunami held in October 2005. The seats were all taken every time.”

“Friends of the Observatory”, which was founded in August 1996, plays an important role in helping weather forecasters improve their services.

The members are local residents who have interests in the work of the Observatory. The organisation now has more than 6,000 members.

Before a new type of service is made public, the members will be the first batch of users to try out the service and give their feedback.

This arrangement has been helping the Observatory solicit views from people from different sectors, Mr Yeung said.

For example, members were given a password to use the new lightning location information service online and submit their evaluation through the website before the service was launched in June this year.

Another case is the “dial-a-weather” service, which was made public in March.

The public can get the most updated weather report by calling 1878200. The members helped simplify the keying procedures of the service.

Even though the Observatory is a department which depends much on technology, it holds a strong belief in the importance of human factor in utilising advanced technology to deliver better services.

The “Happy Business” campaign, which started in January 2004, aims at
producing a pleasant workplace for the staff.

Activities such as games and visits are organised to improve the staff's morale. It also makes an effort to cut long working hours.

“Only when the staff are happy, their work can be done well,” Mr Yeung said.