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The Observatory commences Ultraviolet Index forecast

The Observatory commences Ultraviolet Index forecast
(11 May 2006)

The Hong Kong Observatory commenced the Ultraviolet (UV) Index forecast today (11 May 2006). The service will enable members of the public, when planning outdoor activities, to adopt appropriate protective measures against possible harm from UV radiation.

Measurement and dissemination of UV levels by the Observatory since 1999 was well received by the public. After research and analysis of the data collected during the years, the Observatory recently developed the UV Index forecast service. Starting from today, forecast of maximum UV Index for the next day will be provided at 5:00 p.m. every day. When the UV index is expected to be 11 (corresponding to an extreme UV level) or above, the public will be reminded of the need to take protective measures, such as avoiding prolonged exposure under the sun. The UV forecast information can be obtained through radio, television, Dial-a-Weather service (1878200-313), the Observatory's website (http://www.weather.gov.hk/wxinfo/uvfcst/uvfcst.htm) and Personal Digital Assistant (PDA) website (http://pda.weather.gov.hk/uvfcst.htm).

In a press conference held at the King's Park Meteorological Station, Dr. Lee Boon-ying, Assistant Director of the Observatory, introduced the UV Index forecast service as well as the various types of instruments used in the measurement of UV and solar radiation. Dr. Lee explained, "UV radiation comes from the Sun and on reaching the Earth after passing through the atmosphere, it may be modified by a number of weather factors. By forecasting the weather situation for the next day, the Observatory calculates the corresponding UV index. The purpose of issuing the forecast UV index is to assist members of the public, especially those frequently engaged in outdoor activities, to take necessary protections against exposure to UV."

Also at the press conference was Dr. NG Chi-cheung, Principal Medical and Health Officer of the Department of Health. He said, "Moderate exposure to the sun is good to our health, but overexposure to UV can induce skin and eye injury, photokeratoconjunctivitis, cataract and skin cancer. Therefore, on days when the UV Index is on the high side, one should wear a hat, use an umbrella, wear suitable clothing and apply sunscreen lotion to protect the body. The Observatory's forecast UV Index enables the public to make the necessary precautions against changes in UV."

A trial version of the UV forecast service launched earlier on the Observatory's website has been well received. Lee Lai-shan, Olympic windsurfing gold medalist, said, "We spend a lot of time practicing outdoors and are exposed to all kinds of weather. We got burnt by UV even under seemingly cloudy skies. The UV forecast gives us very useful guidance in taking protective measures." Mr. Lee Chun-wai, Chairman of the Hong Kong Federation of Countryside Activities, also welcomed the new service. "Hikers often stay under the sun for a long time. This service puts us on the alert and allows us to take measures against UV exposure before the journey starts." he said.

For further details about the UV Index forecasting service, please contact Mr. Poon Hoi-to, Senior Scientific Officer of the Observatory (Telephone: 2926 8414 or email: htpoon@hko.gov.hk).

 

Dr. Lee Boon-ying (right) and Dr. Ng Chi-cheung (left) introducing the UV Index forecasting service to the press media at the King's Park Meteorological Station.

Dr. Lee Boon-ying (right) and Dr. Ng Chi-cheung (left) introducing the UV Index forecasting service to the press media at the King's Park Meteorological Station.

 

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