For meteorologists from Guangdong, Hong Kong and Macau, 2004 marks 20 years of co-operating in setting up automatic weather stations in the Pearl River Estuary area.

The three places are now collaborating on setting up a lightning location network covering the area.

Regional co-operation: The first automatic weather station for the Pearl River region was set up on Huangmaozhou, 45 kilometres south of Lantau. With collaborative efforts from meteorologists from HK, Guangdong and Macau, the station commenced operation in 1984.

The network will be capable of determining lightning locations within a short time. The equipment installation will be completed next year, when a lightning location information service will be launched.

Information will be released through the most efficient communication means to ensure that the public and the relevant business sectors receive the latest lightning information and make the necessary preparations.

Weather stations forerunner of regional co-operation

HK Observatory Director Lam Chiu-ying said setting up automatic weather stations in the estuary area was a forerunner of increased regional co-operation in general.

"Through long-term consultation and collaboration among the three places, it has made important contributions to the prevention and mitigation of natural disasters, as well as to the economic development in the area," he added.

In 1984, the Guangdong Meteorological Bureau and the HK Observatory first agreed to cooperate on establishing an automatic weather station on the island of Huangmaozhou, 45 kilometres south of Lantau.

Six stations built to provide weather information

During the past two decades, the three places have jointly established five other automatic weather stations. They are: Tuoning Liedao (1996), Neilingding Dao (1996), Wailingding Dao (1997), Wanshan Dao (1997) and Gaolan Dao (1997).

Providing weather information round-the-clock, these stations afford front-line detection and early alerts, of up to a few hours, of weather approaching the Pearl River Estuary from the sea, especially tropical cyclones. 

Energy limitations, due to lack of city power on the islands, posed a major challenge to meteorological workers.

Computer programme helps solve energy problem

Yau Lai-kin, now a radar specialist mechanic at the observatory, was responsible for developing software for the Huangmaozhou weather station.

"The problem really taxed the capability of observatory colleagues, who succeeded eventually in using solar energy to drive the weather station. However, the electricity generated was still low," Mr Yau said.

"We had to resort to the use of a small, low-power microprocessor board having only a four-kilobyte memory (4,000 bytes), which was several 10,000ths of the memory available in today's personal computers. I was asked to work out under these stringent conditions a small computer program that would carry out all the complex calculations and processes, and succeeded at last after very hard work.

"Over the years the weather station performed very satisfactorily, requiring just a couple of maintenance trips each year."

Rainstorm warning systems to be expanded

Apart from the above weather stations, meteorologists from the three places also established over the years the real-time weather information exchanges through dedicated data lines, the networking of weather radar data from the area, and the closer consultation among forecasters in these places during the approach of severe weather.

They are now expanding the short-range warning of intense rainstorms in localised systems, developed by the HK Observatory, to a rainstorm forecasting system covering the Pearl River Estuary. 

Guangdong Meteorological Bureau Director Yu Yong said he is confident that with further co-operation, all of the meteorologists in the area will be able to make greater contributions in the prevention and mitigation of natural disasters in the Pearl River Estuary.

Macau Meteorological & Geophysical Bureau Director Fong Soi Kun hoped to build on the existing co-operation, to better serve people in the area.