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THE ENVIRONMENT

the highest ever recorded in October. On October 19, Carmen passed about 70 miles south-southwest of Hong Kong and produced gales and widespread heavy rain. The rainfall recorded at the Royal Observatory on October 18-20 amounted to 459.9 mm, which made Carmen the wettest tropical cyclone in October and the fourth wettest on record. Typhoon Elaine also brought 225.2 mm of rainfall to Hong Kong but the contributions from the other two typhoons, Bess and Della, were less than 0.5 mm. Because of the unusual number of tropical cyclones which threatened Hong Kong, signals were hoisted on 15 days of the month. The strong monsoon signal was hoisted on three occasions and fire danger warnings were in operation on three days.

The frequency of tropical cyclones over the western North Pacific and South China Sea remained high in November and December. Altogether, six were observed during these two months. Typhoon Gloria came near the south China coast about 110 miles east of Hong Kong on November 9, causing fresh winds and periods of light rain, while typhoon Irma was responsible for the wettest December on record. More than 95 per cent of the month's total rainfall of 206.9 mm was produced by Irma on December 1-2. The 177.3 mm of rain which fell on December 2 represented the highest daily amount ever recorded in December.

Winter conditions set in around mid-November when temperatures began to fall steadily to generally below 20°C. However, the six cold surges which passed through Hong Kong during the last two months of the year were relatively weak and caused the air temperature to fall below 11°C on only one occasion. Fire danger warnings were in force on 15 days in November and 12 days in December, while the strong monsoon signal was displayed twice in each month.

The Royal Observatory

The Royal Observatory is directly concerned with all matters relating to mete- orology, geophysics and environmental sciences. It provides a diversity of services on a broad spectrum of environmental problems. These services not only play an important role in the economic progress and development in a modern society like Hong Kong, but also help to reduce the possible loss of life and property in natural catastrophes caused by severe weather systems such as thunderstorms, rainstorms and tropical cyclones.

Weather forecasts and tropical cyclone warnings are prepared in the Central Forecasting Office, while services for aviation are provided at the Airport Mete- orological Office.

Close liaison is maintained with all ships visiting Hong Kong and about 36 selected ships are provided with instruments by the observatory to encourage them to transmit weather reports which are used in the preparation of forecasts and for locating tropical cyclones. About 50 weather reports are received each day from ships, through two coastal radio stations in Hong Kong. All reports received are dis- seminated to other centres through the World Weather Watch telecommunication network. About 8,000 weather reports from land stations and ships are received each day from other countries together with aircraft reports and other data. They are