ENG-1982 — Page 316

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THE ENVIRONMENT

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about two days out of three and the average monthly rainfall at the Royal Observatory is 431.8 millimetres. The driest month is December when the monthly average is only 25.3 millimetres and when rain usually falls on only about five days in the month. Climatological information on Hong Kong's weather is given at Appendix 39.

Severe weather phenomena that can affect Hong Kong include tropical cyclones, strong winter monsoon winds, and thunderstorms with associated squalls that are most frequent from April to September. Water-spouts, hailstorms and snow occur infrequently and tornadoes are rare.

The Year's Weather

1982 was the wettest year on record. Rainfall at the Royal Observatory amounted to 3 247.5 mm, which is 46 per cent above the normal figure of 2 224.7 mm. A significant portion of the year's rainfall was due to the heavy rain spells experienced in late May and mid-August.

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There were 28 tropical cyclones over the western North Pacific and the China Seas, and they caused heavy losses to life and property in several Asian countries. However, none of them caused persistent gales in Hong Kong and there was very little damage, although warning signals were displayed for five of the tropical cyclones.

January was warmer and drier than usual. The temperature never fell below 11.5°C and the mean temperature of 16.9°C was 1.3°C above normal. Fire danger warnings were issued on 22 days but about 9 000 people were made homeless in a series of disastrous fires in squatter areas.

February was cloudy and humid. Fog developed in the evening of February 19 and persisted for several days, causing the diversion of aircraft from Hong Kong and the disruption of ferry and hovercraft services. A fishing junk sank after colliding with a container ship in fog south of Po Toi Island on February 23. On February 24, a cold front arrived in Hong Kong and cleared the fog. A fishing junk sank in rough seas in Tathong Channel on February 25 while the strong monsoon signal was hoisted. The mean temperature for the month, 15.9°C, was normal and the minimum temperature recorded at the Royal Observatory was 10.2°C.

March was warmer, cloudier and more humid than usual. Fog was reported at Hong Kong International Airport every morning from March 5 to 7, resulting in the diversion of seven aircraft from Hong Kong. Ferry services were also affected.

April was the seventh wettest April on record. Thunderstorms and heavy showers during the last nine days brought the month's rainfall to a total of 310.0 mm, which was more than double the normal amount.

May was the fourth wettest May on record. Rainfall totalling 653.9 mm was recorded at the Royal Observatory during rainstorms which lasted from May 28 to 31. This amount of rainfall over a four-day period was the second highest record for May. As a result, round-the-clock water supply was resumed in Hong Kong after eight months of water restrictions. Flooding was most serious in the northwestern part of the New Territories and landslips were reported in many parts of Hong Kong. Some 25 people were killed. In addition, four were missing, 100 were injured and more than 8 000 made homeless. About 700 000 head of poultry and 10 000 pigs were drowned; 1 000 hectares of crops and 400 hectares of fish ponds were inundated in the New Territories.

On June 2, a tornado occurred near Yuen Long. It was the first tornado reported in Hong Kong since records began in 1884. Two people were killed and five others were injured. The total rainfall for the month was 205.9 mm, which was slightly less than half