Eight am is the regular time for the daily videophone weather teleconference. Local forecasters all over the country can view the weather predictions made by their counterparts in the Central Meteorological Observatory (CMO) and listen to their analysis.

Li Yangxiang, a chief short-range weather forecaster with the Central Meteorological Observatory, focuses on the computer screen as she maps in isobars. [China Daily]

If local forecasters have different views, they can also express them at this time, so the exchange is as immediate as if forecasters across the country had got together in the same room. The process functions thanks to the VSAT satellite network, which transmits the video images to all the observatories.

Before the network was launched on July 1, the Central Meteorological Observatory consulted with provincial meteorological observatories by videophone only for important festivals or important weather changes.

Now, with the introduction of the network, the accuracy of daily weather forecasts has been improved significantly.

"Videophone teleconferencing was unimaginable for us 10 years ago, but now it plays an important role in our daily forecasts," said Yao Xuexiang, deputy director of CMO.

Two decades into his meteorological career, Yao has witnessed the impressive changes in weather forecasting in China.

The Central Meteorological Observatory was established five months after the founding of the People's Republic of China. The reform and opening to the outside world provided the country's meteorological system with the opportunity for rapid upgrading.

"Weather forecasting in China is up in the front row worldwide," Yao noted.

Radars have also been a valuable addition to meteorologists' tool kit. Plans are to have 127 made-in-China Doppler weather radars deployed, forming a network for the whole country. So far, scores of the Doppler radars are already in operation, according to Yao.

The network utilizes the world's most advanced radar technology, and is capable of observing minor climate phenomena, such as tornadoes and hail, and its accuracy, reliability and applicability are much improved over previous radars.

This summer, the Doppler radars played an important role in monitoring and providing warnings of the rainstorms in the Huaihe River basin.

The meteorological satellites launched by China, including Fengyun-1 series and Fengyun-2 series, have also entered the functional stage.

Data for the precipitation forecasts for the Huaihe River basin and the typhoon and high temperature forecasts in other parts of the country all came from China's own satellites. Previously, Chinese experts had mainly depended on the Japanese GMS satellite, which stopped operation this year.

The medium-range forecast beyond three days mainly depends on the digital weather information provided by super computers, which process a variety of data coming from more than 2,000 surface observation stations, satellites, and Doppler radars.

Listed as one of the CMO's top priorities is also the severe weather report, the frequency and detail of which have been increasing with the country's economic development.

However, there are not yet highly accurate forecasts for all kinds of severe weather situations, Yao noted.

For typhoons, the accuracy is relatively high and generally warnings are issued two or three days in advance. Consequently, the death toll in typhoon disasters has dropped greatly from the levels in the 1970s when typhoons would often inflict thousands or tens of thousands of deaths. Now the numbers are well below 100.

In addition, CMO is very effective in monitoring cold fronts and high temperatures.

But for violent weather, like hailstorms and tornadoes, the forecasts are less accurate and can only predict possible conditions in some regions, which really doesn't yet satisfy common people's needs, Yao said.

The busiest time for meteorological workers is from June through August, when the country enters the flood season, with 40 per cent to 80 per cent of the annual rainfall coming within three months.

As China has a vast territory, the weather conditions may vary significantly in different regions.

"In the CMO, every single day can bring crucial moments," said Yao.

He still remembers clearly that on December 7, 2001, a light snow fell in Beijing. The scene, which could not be more common, brought the entire city to a standstill, as most people weren't prepared and traffic jams were severe.

"There are no slack seasons for us," said Yao.

With social development and environmental changes, people are demanding more from the weather forecast. The fog and sand storm forecasts, once unheard of in weather reports, are getting increasing attention. It is a shared feeling among meteorologists that the responsibilities on their shoulders are getting heavier.

At present, most weather data is gathered from cloud patterns, and collecting the full range of atmospheric information, necessary for raising prediction accuracy, remains a formidable challenge.

"Our present detection techniques make it difficult to read the signature of some climate changes such as the tornado. It is like trying to catch a small fish with a large net," said Yao.

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