THE ENVIRONMENT
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Kong International Airport are also supplied to airline operators through a dedicated web server for pre-flight planning.
The terminal Doppler weather radar (TDWR) at Tai Lam Chung keeps close surveillance of wind shear around the approaches to the airport.
Radiation Measurement and Assessment
The Observatory operates an Environmental Radiation Monitoring Programme to monitor radiation levels in Hong Kong. The programme entails the collection and measurement of samples of air, water, soil and food regularly at several sites. A network of stations monitor the ambient gamma dose rate continuously and warn of any deviation from normal levels. Data are disseminated to the media daily and released in a bulletin every month. The prevailing radiation levels are also published annually.
In 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 Hong Kong. The Observatory will also provide technical advice to the Government on counter-measures. An Aerial Monitoring System will be flown on a helicopter to monitor radiation levels on the ground and at various altitudes over Hong Kong.
A newly developed Emergency Radiation Data Management System automates the collection, processing, retrieval and despatch of radiation data and messages and is capable of handling enormous amount of such data and messages during a nuclear emergency.
Climatological, Oceanographic and Geophysical Services
Climatological information has applications in activities ranging from recreation through engineering design and environmental impact analysis to litigation. To meet the demand for such information, the Hong Kong Observatory operates a climatological information service on a cost-recovery basis. The data available include surface and upper-air observations from Hong Kong and neighbouring countries, marine weather observations from voluntary observing ships and tidal observations.
The Observatory produces an annual tide table for Hong Kong. It also provides assessments of the probabilities of occurrence of extreme storm surges and advice on oceanographic matters to other government departments and the engineering community.
To monitor earthquake activities in the vicinity of Hong Kong, the Observatory operates a network of eight short-period seismograph stations. Long-period seismographs at the Observatory's headquarters detect tremors world-wide and information on significant tremors is made public through the media. In addition, three strong motion accelerographs were installed on different geological sites. On average, Hong Kong experiences two to three minor earth tremors every year.
The Hong Kong Time Standard is provided by a caesium beam atomic clock. Accuracy within fractions of a microsecond a day is maintained. A six-pip time signal is sent to Radio Television Hong Kong for broadcast at quarter-hour intervals. The time checking service is also available to the public through the Observatory's Information Enquiry System. In addition, a time-server was available on the