THE ENVIRONMENT
The Observatory exchanges weather radar images with the Guangdong Meteoro- logical Bureau and operates an automatic weather station at Huangmao Zhou, an island in Chinese waters 40 km south of Hong Kong. In 1994, Guangdong, Hong Kong and Macau agreed to implement a network of automatic weather stations covering a wider area in the Pearl River estuary. This network gives Hong Kong an earlier indication and better timing of the approach of hazardous weather such as fronts, squall lines and tropical cyclones. Using guidance from numerical products from both global and limited area models, forecasters can now issue weather forecasts for several days ahead with reasonable confidence.
Aviation Meteorology
The Royal Observatory operates the Airport Meteorological Office (AMO) at the Hong Kong International Airport to provide services for civil aviation. Besides keeping watch and warning of hazardous weather over the Hong Kong Flight Information Region, the AMO provides flight documentation to aircraft departing Hong Kong. This includes weather forecasts for destination aerodromes, prognostic charts of significant weather en route and forecast wind and temperature data appropriate to cruising levels.
The Observatory is co-ordinating the planning and provision of meteorological facilities for the new airport at Chek Lap Kok. State-of-the-art equipment being procured includes a terminal Doppler weather radar to detect wind shear due to thunderstorms.
Radiation Measurement and Assessment
The Observatory operates an Environmental Radiation Monitoring Programme to monitor radiation levels in Hong Kong. The programme, begun in 1987, entails the collection and measurement of samples of air, water, soil and food regularly at a number of sites in the territory. Measurements from 1987 to 1991 were analysed to determine the background radiation levels in the territory and the results published in early 1993. Thereafter, bulletins on the prevailing radiation levels have been published annually. A network has also been established for continous monitoring of the ambient gamma dose rate in the territory and to warn of any deviation from normal levels. Data are disseminated to the media daily and published in a bulletin monthly.
In the event of an emergency, the Observatory will intensify radiation monitoring and assess the radiological and meteorological information collected to estimate the transport, dispersion and deposition of any radioactivity over the territory. It will also provide technical advice to the government on any necessary counter-measures.
Climatological, Oceanographic and Geophysical Services
Climatological information finds applications in activities ranging from recreation through engineering design and environmental impact analysis to litigation. To meet the demand for such information, the Royal Observatory operates a climatological information service on a cost-recovery basis. The data available include land and upper-air observations from Hong Kong and neighbouring countries, marine weather observations from voluntary observing ships, and tidal observations.
The Royal Observatory produces an annual tide table for Hong Kong. It also provides assessments of the probabilities of occurrence of extreme storm surges and
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