THE ENVIRONMENT
mation of weather chart plotting, the operation of the local telecommunications network and switching of meteorological messages with three overseas centres at Beijing, Tokyo and Bangkok.
In recent years, the vagaries and evolution of weather have become better understood through experience gained in analysing and interpreting the output of numerical weather prediction models computed at the Royal Observatory and other major meteorological centres abroad. With the continuing advances in the accuracy and reliability of numerical model outputs, weather forecasts can now be issued several days ahead with confidence.
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Aviation Meteorology The Royal Observatory operates the Airport Meteorological Office (AMO) at the Hong Kong International Airport to provide meteorological services for civil aviation. Besides keeping watch and issuing warnings of hazardous weather over the Hong Kong Flight Information Region, the AMO is responsible for the provision of flight documentation to aircraft departing Hong Kong. Such documentation includes weather forecasts for departure, destination and alternate aerodromes; prognostic charts of significant weather en route; forecast wind and temperature data appropriate to cruising levels and information on expected occurrences of weather phenomena which may affect the safety of aircraft.
The Royal Observatory is co-ordinating the planning and provision of meteorological facilities for the new airport at Chek Lap Kok. State-of-the-art equipment is being procured to provide detailed meteorological data in the vicinity of the new airport. This will allow timely warnings of hazardous weather for aircraft landing and departure. The equipment will include a terminal doppler weather radar to detect and provide alerts of wind shear due to thunderstorms and microbursts; wind profiler and radio acoustic sounding systems to measure vertical profiles of wind and temperature aloft; and a surface meteorological observing system with sensors to report wind, visibility and cloud base along the runway.
Radiation Measurement and Assessment
In keeping with its responsibilities for emergency response services relating to inclement weather and other natural disasters, the observatory will be responsible for providing advice on the atmospheric behaviour of any accidental release of radioactivity from the Guangdong Nuclear Power Station at Daya Bay, which began commercial operations in February 1994. The observatory operates an Environmental Radiation Monitoring Programme to monitor radiation levels in Hong Kong. The programme, which began in 1987, entails the collection and measurement of samples of air, water, soil and food regularly at a number of locations in the territory. Measurements from 1987 to 1991 have been analysed to determine the background radiation levels in the territory and the results were published in early 1993. Annual bulletins on the prevailing radiation levels will be published. A radiation monitoring network has also been established to monitor continuously the ambient gamma dose rate in the territory and to provide an alert in case of any deviation from normal levels. Since 1993, the collected data has been published 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.
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